BRPI1013838A2 - apparatus and method for analyzing the condition of a machine, method for operating an apparatus, computer program, and, computer program product - Google Patents

Abstract

apparatus and method for analyzing the condition of a machine, method for operating an apparatus, computer program, and, computer program product an apparatus and method for analyzing the condition of a machine having a rotating part, with a rotational speed comprising inputs for receiving a vibration signal, rotational speed and operator control signals. an a / d converter, an envelope, a decimator, a time domain operating intensifier for discrete autocorrelation, and an analyzer for performing a condition monitoring function to analyze machine condition.

Description

APPARATUS AND METHOD TO ANALYZE D CONDITION OF DMA MACHINE. METHOD FOR OPERATING AN APPLIANCE. PROGRAM OF. COMPUTER, AND, COMPUTER PROGRAM PRODUCT ”

Invention field of the Invention

The present invention relates to a method for analyzing the condition of a machine and to an apparatus for analyzing the condition of a machine. The invention also relates to a system including such an apparatus and a method of operating this apparatus. The invention also relates to a computer program to make one. computer performs an analysis function ..

Description of Related Technique

Machines with moving parts are subject to wear and tear over time, which often causes the condition of the machine to deteriorate »Examples of such machines with moving parts are engines, pumps, generators, compressors, tomes and milling machines. Moving parts can comprise an axis and manuals.

X X ..... ..................

In order to prevent machine failure, these machines must be serviced »depending on their condition. Therefore, the operating condition of a machine is preferably assessed periodically. The operating condition can be determined by measuring vibrations emanating from a manual or by measuring the temperature in the machine housing, whose temperatures depend on the operating conditions of the bearing. These condition checks of machines with rotating parts or other moving parts are of great importance for safety and also for the life of these machines. It is known to perform these measurements manually on a machine. This is normally done by an operator »with the help of a measuring instrument, performing measurements at measuring points on one or more machines.

Numerous commercial instruments are available, based on the fact that defects in rotating element bearings generate short pulses, usually called shock pulses. A shock pulse measuring device can generate a formation indicative of the condition of a bearing or a machine.

WO 03062766 discloses a machine having a measuring point and an axis with a determined axis diameter, where the axis can rotate when the machine is in use. WO 03062766 also discloses an apparatus for analyzing the condition of a machine having an axis of rotation. The device shown has a sensor to produce a measured value indicating a vibration in a measuring porn. The apparatus shown in WO 03.062.766 has a data processor and a memory. The memory can store program code which, when run on the data processor, will cause the analyzer to perform a Machine Condition Monitoring function. This Machine Condition Monitoring function may include shock pulse measurement.

The UK patent application GB 2J90.19 & A presents a vibration analysis system to analyze the operation of a machine having a periodically repeated operating cycle. GB 2.A 90.198A teaches how to provide 20 vibration detection means that, in use, are operably linked to the machine, and a monitor that generates signals related to the machine's speed. An analog vibration signal is transmitted through the vibration detection medium through an amplifier to an envelope stage and from there to an A / D converter operating to sample the analog vibration signal 25 at a rate of, for example, 36,000 analog conversions -paradigital per cycle. The converted A / D signal is transmitted to a sampler operating to average each consecutive set of ten values represented by the output of the analog-to-digital converter! to thereby obtain 3,600 samples of vibration values. These samples can be provided, through a time-based controller, to a sample average calculator having bare recorders which accumulate vibration values for corresponding points in the machine's operating cycle for a plurality of cycles. The total value in each of the several 5 registers is divided by the number of operating cycles to give a linear arithmetic mean of the vibration value for each sampling point within the machine's operating cycle. At the end of a predetermined number of operating cycles on which the analysis operation was carried out, the series of average vibration values will represent the average vibration 10 experienced at the location of the means for detecting vibration for the machine's operating cycle, or that is, in the time domain. The vibration analysis system, according to GB 2J90J98, also includes a means of identifying the operating event to determine the occurrence of an event in the operating cycle as revealed by the average vibration values. In this way, it may be possible to identify faults and other events, in accordance with GB 2,190,198.

summary

One aspect of the invention concerns the problem of preventing the unexpected breakage of the equipment due to mechanical wear, or damage, on a machine having a rotating part with a speed of rotation.

This problem is solved by one. apparatus to analyze the condition of a machine having a rotating part with a speed of rotation, which includes:

2 is an input for receiving an analog measurement signal indicative of a vibration signal signature having a vibration frequency and a repetition frequency;

an A / D converter for generating a digital measurement signal dependent on the analogue measurement signal, said digital measurement signal having a first sample rate, the first sample rate being at least twice the vibration-frequency menciomide;

an encoder to generate an envelope signal indicative of the said repetition frequency;

a decimator for generating a first decimated digital signal dependent on said enveloped signal. so that said first decimated digital signal has a reduced sample rate;

Λ y,. ·, · .. · an Intensifier having an input to receive the said decimated signal, where the intensifier operates in the time domain to perform discrete correlation for the first decimated digital signal, in order to generate a sequence of signal intensifier output, and an analyzer to perform a condition monitoring function in order to analyze the condition of the machine depending on the mentioned intensifier output signal sequence,

This solution has the advantageous effect of allowing early detection of incipient damage, that is, the early detection of damage that is just beginning to develop, on a machine having a rotating part with a rotation speed. Early detection is possible, since the amplitudes of stochastic signal components are significantly reduced in relation to the repetitive signal signature in the sequence of the intensifier output site, allowing, from this rn.od.rn, that the anahsador generates data indicative of a diagnosis of the said incipient damage based on the intensified output signal sequence Maintenance of the machine can be carried out on the basis of such a diagnosis and, if the diagnostic data indicates an imminent risk of machine breakage, then the machine, or the monitored rotating part can be interrupted or detached. in order to avoid breaking the machine.

It is known that machine breakdown occurs unexpectedly in certain machines, even when the machine is subjected to a substantially continuous morbidity. This unexpected break is significant for the machine owner and I was able to cause other negative side effects, for example »if the machine parts are damaged.

detach as a result of unexpected mechanical failure,

It was noticed that there is a particularly high level of noise in the mechanical vibrations of some machines, and that the noise levels make it difficult to detect damage to the machine. Consequently, for some types of machines, conventional methods for preventive condition monitoring have been tailored to provide sufficiently early and / or reliable warning of deteriorating conditions to occur. It was concluded that there may be a mechanical vibration V ^ n indicative of a deteriorated condition in these machines, but that conventional methods for measuring vibrations can, until then. Reading has been inadequate. It was realized that this inadequacy 1.5 of conventional analysis systems may have been due to the sinaFruidu, SNR, ratio of the measurement signal being so low as to prevent or hinder the detection of any vibration signal component indicative of incipient damage.

It was also realized that machines with slowly rotating crashes were among the types of machines that seem to be particularly prone to sudden or unexpected carvings or breakage. Was. also realized that a low rotation speed f _R0T can lead to amplitudes of. mechanical vibrations are less than those that would be the case if the rotation speed were higher. When the 25 V _M : _X mechanical vibration indicates incipient damage to the machine, it has a low amplitude,

the noise content in the sign of me < iition will be greater in i relative wastes. When measure on a machine with ve rotation profitability there: xiixo de SOrprn, the signal digital envelope measurement and deducted. how m Ovido by the decimator. can be noisy enough to prevent the dwarf successful lysis of

eondican monitor. if the decimated digital measurement signal is 'a:' Xs ·:

fed directly to the analyzer. In other words, the signal · · noise ratio, SNR., Of the decimated digital measurement signal can be so low as to prevent or hinder the detection of any component of vibration signals S _t >

'Having realized that a particularly high noise level in the mechanical vibrations of some machines makes it difficult to detect damage to the machine, a method has been presented to enable the detection of weak mechanical signals in a noisy environment, As mentioned above, the 10 repetition frequency f _u of vibration signal component Sn in a noisy measurement signal Sr _A% depends on mechanical vibration that is indicative of incipient damage to a rotating part of the monitored machine, It has been realized that it may be possible to detect incipient damage, or . that is, a damage that is just beginning to develop, if a corresponding weak signal can be identified.

Therefore, the measurement signal can include at least one vibration signal component S _D dependent on a vibration movement of the rotatingly moving part; wherein said vibration signal component has a repetition frequency fb which depends on the rotation speed f _RO i of the rotatingly movable part. The existence of a vibration signal component that is dependent on the vibration movement of the rotatingly moving part can therefore prove an early indication of a deteriorating condition or incipient damage to the machine in the monitor.

A. the claimed solution advantageously makes it possible to detect two different damage signatures S;>_; which can have different repeating frequencies, different fdl, fd2. Therefore, the header header is advantageously adapted to intensify different signatures having mutually different repetition frequencies f _m and q> ₂ . In this context, both values of repetition frequency tfe and 1¼ are proportional to the rotation speed of the monitored rotating part, while the repetition Iroquèneia f _P was different from the repetition frequency.

According to a method of making the apparatus, the intensifier is adapted to process a first plurality of input sample values of said first digital signal, so as to generate an output signal sequence having a second plurality of sample values of output; said second plurality 10 being a positive integer.

The detection and collection of a high frequency vibration signal signature, which can be indicative of a deteriorated condition, requires a sampling frequency, which. according to Nyquist's criterion, it must be at least twice the maximum frequency of the vibration signal signature. Consequently, this collection process inevitably results in a relatively large number of sample values in the digital measurement signal. Consequently, although a large number of sample values are required in the detection and collection of measurement sample values, it is desired to keep the amount of data to be processed in the intensifier as low as possible,

The solution, according to claim 1, advantageously defines the conflicting requirements to allow the detection and collection of a relatively high vibration frequency signal signature with a vibration frequency that after the A / D conversion generates a large number of sample values; while providing a sufficiently low number of sample values as input to the intensifier. to minimize the amount of calculations needed during the processing of the intensi header signal.

\ ^: es? e comevmx the provision of the

... _λ .

envelope and decimator. so that u generate a first digital signal with a pointer Indicative of the mentioned repetition frequency, so that the said first digital signal with a reduced sampling rate, dispenses, for the intensifier, a condensed repetitive signal signature that can be indicative of a deteriorated condition.

According to an embodiment of the invention, a method is provided for analyzing the condition of a machine having a rotating part with a speed of rotation, comprising the steps of:

receiving a first time-dependent digital signal dependent on mechanical vibrations emanating from the rotation of said part; said digital signal having a sample rate; wherein said first digital signal may include noise and a first signal signature reading a first repetition frequency, comprising, additively,;

processing a first plurality P1 of sample input values of said first digital signal so as to generate an output signal sequence having a second plurality P2 of sample output values; said output signal sequence being a 2 () time domain signal sequence; where said processing of said first plurality P1 of input sample values involves a third plurality P3 of multiplications of input sample values to generate an output sample value, so that the generation of said second 2nd P2 plurality of values sample output involves at least a fourth P4 plurality of multiplications.

One aspect of the invention relates to an apparatus for analyzing the condition of a machine having a rotating part with a speed of rotation, which comprises a first input to receive a first digital signal depending on mechanical vibrations> emanating from the rotation of said part ; said first digital signal having a sample rate; where said first digital signal may include noise and a first signal signature having a first repetition frequency:

an intensifier for processing a first plurality of input sample values of said first digital signal in order to generate an output signal sequence having a second plurality of output sample values: said second plurality being a positive integer ;

an analyzer to perform a condition monitoring function in order to analyze the condition of the machine depending on the said output signal sequence; where the intensiíkador includes:

at least a second entry to receive data indicative of said second plurality; c an output for dispensing said output signal sequence; where · said miensifier is adapted to generate an output sample value depending on a third plurality of input signal products; said third plurality being a positive integer; where an input signal product for an output sample position t. is obtained by using a first input sample value in a first sample position for a second sample input value in a second sample position, the aforementioned second sample input being separated from the aforementioned first input sample value by a specified number of sample positions, where the mentioned number is equal to or greater than a given value:

the intensilkador comprising, additionally:

at least a third entry to receive data indicating an increased value? ' the Signal-Noise Ratio; and means for generating a value of data indicative of said third plurality depending on said incententative value of the Signal-Noise Ratio and said data indicative of said second plurality.

This solution enables a successful assessment of the condition of a machine, even when the digital measurement signal received is very noisy.

According to an embodiment of the invention, said means for generating a data value indicative of said third plurality is adapted to receive data indicative of said first plurality, and data indicative of second plurality, and data indicative of said determined value, and where said method for generating a data value indicative of said third plurality is adapted to establish the third plurality value C <'ompr? ment <' equal to the difference between the value Icomprímento and the sum of the values and the length.

According to an embodiment of the invention, said means for generating a data value indicative of said third plurality is adapted to receive data indicative of said second plurality, and data indicative of said value worthy of the Signal-to-Noise Ratio, and where said means for generating a data value indicative of said third plurality is adapted to establish the value of the third plurality equal to the product of the value of the second plurality by the incremental value of the Signal-Noise Ratio.

This solution allows the user to establish a level of improvement of the Smai-Noise Ratio to be obtained in an easy and user-friendly way.

A specie of the invention refers to a method for analyzing the condition of a machine having a rotating part, with a speed of rotation, comprising the steps of:

receiving a first time-domain digital signal dependent on mechanical vibrations emanating from the rotation of said 10 part: said first digital signal reading a sample rate; wherein said first digital signal may include noise and a first signal signature having a first repetition frequency 'further comprising:

processing a first plurality P1 of incoming sample values of said first digitized signal so as to generate an output signal sequence having a second plurality P.2 of outgoing sample values; said output signal sequence being a time domain signal sequence: where said processing of said, first plurality P1 of input sample values involves a third plurality P3 of multiplication of input sample values to generate a value of master.st.ra of .output so that the generation of said second plurality P2 of sample output values involves a fourth plurality P4 of multiplications through the menus.

According to an embodiment of the invention, the method comprises the steps of:

receive data indicative of a value worthy of the Signal-to-Noise Ratio; and generating a value of given mdleatms of the aforementioned third plurality depending on the said incremental value of the Signal-to-Noise Ratio and of the aforementioned data indicative of said-second plurality.

Brief Description of the Drawings

For the simple understanding of the present invention, it will be described by means of examples and with reference to the accompanying drawings, in which Sift Fig. .1 shows a schematic block diagram of an embodiment of a condition analysis system 2. according to one. embodiment of the invention.

Fig. 2A is a schematic block diagram of an embodiment of a part of the condition analysis system 2> shown in Figure L

Λ Fig. 2B is a schematic block diagram of an embodiment of a sensor interface.

Figure 2C is an illustration of a signal measuring a vibration sensor.

2D Figure 2D illustrates a measurement signal amplitude generated by a gnocchi pulse sensor.

The 2E figure illustrates a measurement signal amplitude generated by a vibration sensor.

Figure 3 is a simplified illustration of a Shock Pulse Measurement sensor according to an embodiment of the invention.

Figure 4 is a simplified illustration of an embodiment of memory 60 and its contents.

Figure 5 is a schematic block diagram of an embodiment of an analyzer at a customer location with a machine 6 reading a moving axis,

Figure 6 illustrates a schematic block diagram of an embodiment of the pre-processor, in accordance with an embodiment of the present invention,

Figure 7 illustrates an embodiment of the evaluator 230.,

Figure 8 illustrates another embodiment of the evaluator 230.

Figure 9 illustrates another embodiment of the preprocessor, 200

Figure 10A is an illustration showing ways of carrying out a method for intensifying signal patterns, repetitive in signals,

Figure 10B is an illustration illustrating a method of generating a digital output signal. Figure 10C illustrates an embodiment of the Header device.

Figure 10D illustrates signals according to an embodiment of the intensified method

The figure. 10E Illustrates a way of carrying out a method of operating an intensi Header user interface,

Figure 10F illustrates an embodiment of a method of operating the intensi Header.

Figure 10G illustrates another embodiment of intensifier 3 20,

Figure 10H is a table to illustrate part of the calculation of the output signal values.

Figure 11 is a schematic illustration of a first memory having several memory locations

Fioura 12, is an esauemáuca illustration of a seaunda

V · '’s'>

memory having multiple memory locations t,

Figure 13 is a schematic illustration of an example of an output signal comprising two repetitive signal signatures.

Figure 14A illustrates various sample values in the signal dispensed for the input of the decimator 310.

Figure 14B illustrates sample values from the current 5-period period.

The 15th figure illustrates a decimator. according to an embodiment of the invention.

Figure 15B illustrates another embodiment of the invention,

Figure 16 illustrates an embodiment of the invention including a decimator and an intensifier, as described above, and a fractional decimator,

Figure 17 illustrates an embodiment of the fractional decimator.

Figure 18 illustrates another embodiment of the fractional decimator 15.

Figure 1.9 illustrates the decimator and another embodiment of the fractional decimator.

Figure 20 is a decimator block diagram and yet another embodiment of a fractional decimator.

Figure 21 is a flow chart illustrating an embodiment of a method of operation of the decimator and the fractional decimator of Figure 20.

Figures 22A, 22B & 22C describe a method that can be implemented as a computer program.

23 Figure 23 is a front view illustrating a gear system

Figure 24 is a schematic side view of the epicyclic gear system 700. of Figure 23, as seen in the direction of the arrow SW. in Fig.ttra 23.

25 Figure 25 illustrates an analog version of an exemplary signal produced by the 200 processor (see Figure S or Figure 16) in response to signals detected by at least one sensor 10. when the epidelien gear system is rotated.

Figure 26 illustrates an example of a portion of the high amplitude region 702A of the signal shown in Figure 25.

Figure 27 illustrates an exemplary frequency spectrum of a signal comprising a small periodic disturbance 903. as shown in Figure 26.

Figure 28 illustrates an example of a portion of the exemplary signal shown in Figure 25.

Figure 29 further illustrates an embodiment of a condition analysis system, according to an embodiment of the invention.

Figure 30 is a block diagram illustrating the parts of the signal processing arrangement of Figure 29, together with the user interface and the display.

Figure 31 is a schematic illustration of a parameter controller.

Detailed description of embodiments

In the following description, similar characteristics in different embodiments can be indicated by the same reference numerals.

Fig. 1 shows a schematic block diagram of an embodiment of a condition analysis system 2, according to an embodiment of the invention. Reference numeral 4 refers to a customer location having a machine 6 having a moving part 8. The moving part may include bearings 7 and an axis 8 which when the machine is in operation, rotates. The operating condition of axis 8, or of a handle 7,

6 can be determined in response to vibrations emanating from the shaft and / or the bearing when the shaft rotates. The location of customer 4, which can also be referred to as the customer part or user part, could, for example, be the premise of a wind farm, that is, a group of wind turbines in one location, or the premise of a paper mill, or any other mill facility with other machines with moving parts.

One embodiment of the condition analysis system 2 is operational when a sensor 10 is coupled on, or, at a measurement point 12 on the body of the machine 6. Although Figure 1 illustrates only 10 two measurement points 12, it must it will be understood that location 4 can comprise any number of measuring tips 12. The condition analysis system 2 shown in Figure 1, comprises an analysis device 14 for analyzing the condition of a machine based on measurement values provided by the U sensor).

The analysis apparatus 14 has a communication port 16 for bidirectional data exchange. Communication port 16 is connectable to a communications network 18. for example, via a data interface .19, communications network 18 may be the worldwide network, also known as the Internet. Communications network 18 may also include a public switched telephone network.

A server computer 20c connected to communications network 18. Server 20 may comprise a database .22, user input / output interfaces 24 and processing hardware data 26, and a communication port 29, The server 25 computer 20 is located in a location 28 geographically separate from the location of client 4. The location of server 28 can be in a first, city, such as Stockholm, the capital of Sweden, and the location of the client can be in another city, such as Stuttgart, Germany or Detroit, Michigan, USA. Ahernatively, the location of the server 28 can Gear in a first part of a city and the location of the client in another. crash of the same dog. The formulation of the sensor can be referred to as the supply part 28, or the location of the supply part.

According to an embodiment of the invention a central control location 31 comprises a control computer 33 hardware and software for data processing for surveying a plurality of machines at the customer's location 4. The machines 6 can be wind turbines or gearboxes used in wind turbines. Afternutively machines can include machines _; for example, a paper mill · Control computer 33 may comprise a 22B database, 24B user input / output interfaces and 26B data processing hardware, and a 29B communication port. The location of the central shuttle 31 can be separated from the location of customer 4 by a geographical distance. Through the communication port 15B, the control computer 33 can be coupled to communicate with the analyzer 14 via port 16. The analyzer 14 can dispense with partially processed measurement data in order to allow for further processing of signals and / or that the analysis is performed at the central location 31 by the control computer 33,

2 (1 The supplying company occupies the location of the supplying party

28. The supply company was able to sell and dispense analysis devices 14 and / or software for use in an analysis device 14. The supply company can also sell and dispense analysis software for use on the control computer at the central control location 31. This analysis software 25 94.105 will be explained in connection with Figure 4 below. This 94.105 analysis software can be dispensed by transmission via the mentioned communications network 18. According to an embodiment of system 2, the device 14 is a portable device that can be connected to the communications network 18 from time to time.

According to another embodiment of system 2, the apparatus 14 can substantially receive a measurement signal from a Ui sensor continuously to enable continuous monitoring, or. practically continuous, the condition of the machine. The apparatus 14, according to this embodiment, can also substantially be able to communicate continuously with the control computer 33 at the control location 31. Accordingly, the apparatus 14, according to this embodiment , can substantially always be available online for communication with the control computer 33 at the control location 31.

1.0 According to an embodiment of system 2, the apparatus 14 is connected to the communications network 18 substantially continuously. Therefore, apparatus 14, according to this embodiment, can always be substantially "on line", available for communication with the supply computer 20 and / or with the control computer 15 at the control location 31,

Fig. '2A is a schematic block diagram of an embodiment of a part of the condition analysis system 2 shown in Figure 1. The condition analysis system, as illustrated in Figure. 2À, comprises a sensor unit 10 for producing a measured value. The measured value can be dependent on movement or, more precisely, dependent on vibrations or shock pulses caused by the bearings, when the shaft rotates.

An embodiment of the condition analysis system 2 becomes operational when a device 30 is mounted firmly on or at a measuring point 25 on a machine 6. Device 30, mounted on the measuring point, can be referred to as a pin 30 A plate 30 may comprise a connection coupling 32 to which the sensor unit 10 is removably attachable. The connection coupling 32 may comprise, for example, double Initial threads to allow the sensor unit to be fitted mcearaleatucnie to the pin by means of.

A measuring point 12 may comprise a threaded recess in the machine housing. A pin 30 could have a protruding part with threads corresponding to those of the recess, muting to allow the pin 5 to be firmly coupled to the measurement point by inserting it into the recess like a screw »

Alternatively, a measuring point may comprise a threaded recess in the machine housing, and the sensor unit 10 could comprise corresponding threads so that it can be inserted 10 directly into the recess. Alternatively, the measuring point is marked on the machine housing only with a painted mark.

, Machine 6, exemplified in Fig. 2A, may have a rotary axis with a determined axis diameter dl. The axis on the machine 24 can rotate with a rotation speed V1 when the machine 6 is in use.

The sensor unit 10 can be coupled to the apparatus 14 to analyze the condition of a machine. With reference to figure 2A, the analysis apparatus comprises a sensor interface 40 for receiving a measured signal, or measurement data, produced by sensor 10. Sensor interface 40 is coupled to a data processing means 50 capable of to control the operation of the analyzer 14 in accordance with the program code. () data processing means 50 is also coupled to a memory 60 for storing said program code.

According to an embodiment of the invention a. Sensor interface 40 comprises an input 42 to receive an analog signal, the input 25 of 42 being connected to an analogue-to-digital (A / D) converter 44, whose digital output 48 is coupled to the data processing medium 50. The converter A / D 44 sample u analog signal rc-received with a certain sampling frequency i's, in order to dispense a digital measurement data signal S _{M (} > having the mentioned determined sampling frequency 0, and where the amplitude of each sample depends the amplitude of the analog signal received at the time of sampling.

According to another embodiment of the invention, illustrated in Fig. 2B, the sensor interface 40 comprises an input 42 for receiving an analog signal S ^ a from a Shock Pulse Measurement Sensor-, a conditioning circuit 43 coupled to receive the analog signal, and an A / D converter 44 coupled to receive the conditioned analogue signal, from conditioning circuit 43, The A / D converter 44 samples the conditioned analogue signal received with a certain sampling frequency íy, so as to dispense a digital measurement data signal having the mentioned, certain frequency sampling rate f _s and where the amplitude of each sample depends on the amplitude of the analog signal received at the time of sampling,

The sampling theorem ensures that limited band signals (that is, signals that have a maximum frequency) can be perfectly reconstructed from their sampled version, if the sample rate fr is more than twice the maximum frequency of the analog signal S _gA to be monitored. The frequency equal to half the sample rate is. therefore, a theoretical limit to the highest frequency that I could be ignored represented by the sampled signal Smu- Fs This frequency (half the sample rate) is called the Nyquist frequency of the sampling system. Frequencies above the Nyquist f \ frequency can be observed in the sampled signal, but its frequency is ambiguous. That is, a frequency component with frequency f cannot be distinguished from other components with frequencies B * f <* f. and B * f _N - f for integers B, other than zero. This ambiguity, known as aliasing, can be handled by filtering the signal with an anti-aliasing fdt.ro (usually a low-pass filter cut close to the Nyquist frequency) before converting the sampled discrete representation.

In order to provide a safety margin in terms of allowing a non-ideal filter to have a certain slope in the frequency response, the sampling frequency can be selected for a value greater than 2. Therefore, according to 5 embodiment of the invention the sampling frequency can be established as fS ™ k * on.de k is a factor of having a value greater than 2.0

Consequently, ion k can be selected for a value greater than 1.0. 2.0. Preferably, the k-factor can be selected to be a value between 2.0 and .2.9, in order to provide a good safety margin, while avoiding unnecessarily generating many sample values. According to one embodiment, the k factor is advantageously selected so that 100 * k / .2 becomes an integer. According to an embodiment, the k factor can be set to 2.56. The selection of k. to 2.56 provides 1 (X) * k ™ 256 ™ 2 raised to 8.

According to an embodiment, the frequency of. sampling fS of the data signal the digital measurement S _M n cannot be set as a determined value IS. so that, for example, fS “102kHz

Therefore, when the sampling frequency fi, the maximum frequency fo, p is set to a determined value f $ _; ^ _{n & x} of the analog signal S ^ a will be:

Issà ^ s l s / k where fsKAnusx is the highest frequency to be analyzed on signal 25 sampled

Therefore, when the sampling frequency f _{s is} fixed at a determined value i's 102.400Hz, and the k factor is set to 2.56, the maximum frequency of the analog signal Sla will be:

tsr - is / k - 102,400 / 2.56 - 40k.Hz

Consequently, a digital measurement data signal Ss' ,. having a determined sampling frequency fij is generated in response to said analogue measuring signal received Sj, „v The digital output 48 of the converter Λ / 1) 44 · and coupled to the data processing medium 50 via an output 49 of the interface of sense? 40, so as to dispense the digital measurement data signal to the data processing medium 50,

The sensor unit 10 can comprise a vibration transducer, the sensor unit structured to physically fit the connection coupling of the measuring point, so that the vibrations of the 1.0 machine, at the measuring point, are transferred to the vibration transducer . According to an embodiment of the invention, the sensor unit comprises a transducer reading a piezoelectric layer. When the measuring point 12 vibrates, the sensor unit 10, or at least a part of it also vibrates, and the transducer then produces an electrical signal on which the frequency and amplitude will depend on the frequency of the mechanical vibration and the amplitude. vibration of the measurement point 1'2, respectively. According to an embodiment of the invention, sensor 10 is a vibration sensor, providing an analog signal of amplitude of, for example, 10mV / g in the frequency range of 1.00 to 10,000 Hz. This vibration sensor 20 is designed to provide substantially the same amplitude of 10 mV regardless of whether it is exerted for the acceleration of Ig (9.82 m / s ~) at 1 Hz, 3 Hz or 10 Hz. Therefore, a typical vibration sensor has a linear response over a specified frequency range of up to approximately 10kHz. Mechanical vibrations in this '25 frequency range emanating from rotating machine parts are usually caused by imbalance or misalignment. However, when mounted on a machine, the linear response vibration sensor normally also has several different mechanical resonance frequencies depending on the physical eam.in.ho between the sensor and the source of vibration.

Damage to a roller bearing in elastic waves ................

relatively sharp, known as shock pulses, moving along a physical path in a machine housing before reaching the sensor. These shock pulses often have a wide frequency spectrum. The amplitude of a roller bearing shock pulse is typically less than the amplitude of a vibration caused by unbalanced or misalignment.

Shock frequency signatures of a wide frequency spectrum enable them to activate a 'touch response', or resonance, at a resonance frequency associated with the sensor. In this way, a typical measurement signal from a vibration sensor can have a waveform as shown in Figure 2C, that is, a dominant low frequency signal with a lower amplitude and higher frequency resonant ring response superimposed.

In order to allow the analysis of the shock pulse signature, often resulting from damage to a bearing, the low frequency component must be filtered. This can be achieved through a high-pass filter or through a band-pass filter. However, these filters must be adjusted so that the low frequency signal portion is blocked while the high frequency signal portion is passed. An individual tank vibration sensor typically, a resonance frequency associated with the physical path of a shock pulse signal source, and a different resonance frequency associated with the physical path of another shock pulse source, as mentioned in the US 6,053,047. Therefore, the filter washer for the purpose of passing the high frequency signal portion requires individual adaptation when a vibration sensor is used.

When this filter is adjusted correctly the resulting signal will consist of the shock pulse signature (s). However, the analysis of the shock pulse signature (s) emanating from a vibration sensor is somewhat hampered by the fact that the amplitude response, as well as, the resonance frequency varies, inherently, depending on the physical path shock pulse signal sources.

Advantageously. these drawbacks associated with vibration sensors can be alleviated by using a Shock Pulse Measurement sensor. The Shock Pulse Measurement sensor is designed and adapted to provide a pre-determined mechanical resonance frequency, as described in more detail below,

This feature of the Shock Pulse Measurement 1.0 sensor advantageously provides repeatable measurement results. due to the fact of sma! output of a Shock Pulse Measurement sensor to have a stable, substantially independent resonance frequency over the physical path without dependence on the shock pulse signal source and the shock pulse sensor. shock 15 mutually different individuals provide a small deviation, if any, in the resonance frequency.

An advantageous effect of this fact is that the signal processing is simplified, since the filters do not need to be adjusted individually, unlike the case described above, when 20 vibration sensors are used. In addition, the amplitude response of the shock pulse sensors is well defined, mute tie that an individual measurement provides reliable information when the measurement is performed according to the appropriate measurement methods, defined by S.P.M. Instrument AB,

Figure 2D illustrates a measurement signal amplitude generated by a shock pulse sensor, and Figure 2E illustrates a measurement signal amplitude generated by a vibration sensor. Both sensors were subjected to the same, series of mechanical shocks without the typical low frequency signal content. As seen clearly in Figures 2D and 2E, the duration of a resonance response to a shock pulse signature from the Shock Pulse Measurement sensor is shorter than the resonance response corresponding to a shock signature pulse from vibration sensor, This feature of the Shock Pulse Measurement sensor to provide responses from different shock pulse signatures has the advantageous effect of providing a measurement signal from which it is possible to distinguish between different mechanical shock pulses that occur within of a short time.

According to a modification of the invention, the sensor is a gnocchi pulse measurement sensor. Figure 3 is a simplified illustration of a shock pulse measurement sensor 10, according to an embodiment of the invention. . According to this embodiment, the sensor comprises a part 110 having a certain mass or weight and a piezoelectric element 12 (1 The piezoelectric element 120 is somewhat flexible so that it can contract and expand when subjected to external force. The element piezoelectric 120 is provided with electrically conductive layers 130 and 140, respccti.vamen.te, on opposite surfaces As the piezoelectric element 120 contracts and expands it generates an electrical signal which is collected by conductive layers 130 and 140, thus , a mechanical vibration is transformed into an analog electrical measurement signal Sr _A , which is dispensed by the output terminals 145 * 150, Q piezoelectric element 120 can be positioned between the weight 1. .10 and a surface 160 which, during the operation, it is physically coupled to measurement point 12, as shown in Figure 3.

The shock pulse measurement sensor 10 has a resonant frequency that depends on the mechanical characteristics of the sensor, such as the mass m of the mass part 110 and the resilience of the piezoelectric element 120. Thus, the piezoelectric element has an elasticity and a spring constant of k, The mechanical resonance frequency Irm for the sensor is therefore also dependent on the mass m and the spring constant k.

In a method acordc du embodiment of the invention, the mechanical resonance Irequênria f P ^ _RM to the sensor PC it can be determined following equation;

Ir · Ι ^ζ (2π) ν (k / m) (EQ 1)

According to another embodiment of the invention the actual mechanical resonance frequency of a shock pulse measurement sensor 10 can also depend on other factors, such as the nature of the coupling of the sensor 10 to the machine body 6.

1.0 The shock pulse resonance measurement sensor 10 is therefore partly sensitive to vibrations having a frequency at or near the mechanical resonance frequency f _RM . The shock pulse measurement sensor 10 can be designed so that the mechanical resonance frequency Ir is somewhere in the range of 28kHz to 15kHz. According to another embodiment, the mechanical resonance frequency í _R m is somewhere in the range of 30kHz to 35kHz.

In this way, the electrical analog measurement signal has an electrical amplitude that can vary across the frequency spectrum. In order to describe the theoretical context, it can be assumed that. if the shock pulse measurement sensor 10 is subjected to mechanical vibrations with identical amplitude at all frequencies »from, for example, 1Hz to, for example, 200,000kHz, then the amplitude of the analog signal Sk .. \ of the sensor shock pulse measurement will have a maximum in the mechanical resonance frequency f _K M> since the sensor will resonate when being 'pushed' with. this frequency.

With reference to Figure 2B, the conditioning circuit 43 receives the analog signal S ^ _{? A.} The conditioning circuit 43 can be designed to be an impedance matching circuit designed to adapt the input impedance of the A / D converter, as seen from sensor terminals 145, 150 so that optimal signal transfer occurs. From this mute, the conditioning circuit 43 can operate to adapt the input impedance Z .. _h as seen from the sensor terminals 145, 150 so that a maximum electrical power of energy is dispensed for the A / D 44 conversation. According with an embodiment of conditioning circuit 43, the analog signal is fed to the primary winding of a transformer, and a conditioned analog signal is dispensed by one. secondary transformer winding, The primary winding has nl turns and the secondary winding has ri2 turns, the nl / n2 ratio ·· n _{? 2} Thus, the A / T converter 44 is coupled to receive the conditioned analog signal from the circuit conditioner 43. The A / D converter 44 has an input impedance Zu and the input impedance of the A / D converter 44, as can be seen from the sensor terminals 1.45, 150 will be (nl / rt2) ² * Ζ « ₄ , when the conditioning circuit 43 is coupled between sensor terminals 145, 150 and the input terminals of the A / D converter 44,

The A / D converter 44 samples the conditioned analog signal received with a determined sampling frequency L in order to dispense a digital measurement data signal Smd having the mentioned sampling frequency R and where the amplitude of each sample depends on the amplitude of the signal analog signal received at the time of sampling. According to ways of carrying out the. the digital measurement data signal Sm1> is dispensed to a 1.80 medium for processing the digital signal (see Fig, 5).

According to an embodiment of the invention, the means 180 for processing the digital signal comprises the data processor 50 and program code to cause the data processor 50 to process the digital signal. According to an embodiment of the invention, processor 50 is personified by a Digital Signal Processor. The Digital Signal Processor can also be referred to as a DSP.

With reference to Figuni 2A. a data processing means 50 is coupled to a memory 60 for storing said program code. Λ program memory 60 is. preferably, a non-volatile memory. Memory 60 can be a read / write memory, that is, allowing both the reading of data from memory and the writing of new data into memory 60. According to one embodiment, program memory 60 is personified by a FLASH memory, program memory 60 was able to comprise a first segment of memory 70 to store a first set of program code 80, executable in order to control the analyzer 14 to perform the basic operations (Figure 2A and Figure 4) The program memory may also comprise a second segment of memory 90 for storing a second set of program code 94. The second set of program code 94, in the second segment of memory 90, may include program code to cause the analysis apparatus processes the signal, or signals, detected in order to generate a pre-processed signal or a set of pre-processed signals. Memory 60 may also include a third segment of memory .100 for storing a third set of program code 104. Program code set 104, in third memory segment 100, may include program code to make the apparatus run an analysis function selected 105, When an analysis function is executed, this can cause the analysis device to display one. corresponding analysis result in user interface 106 or that dispense the analysis result through port 16 (Fig, I and Fig, 2A and Figures 7 and 8),

The data processing means 50 is also coupled to a read / write memory 52 for storing data. In addition, data processing means 50 can be coupled to a data interface.

2Q analyzer communication 54. The analyzer communication interface 54 provides direct communication with a measuring point communication interface 56 coupled over or near the measuring point on the machine.

The measuring point 12 can comprise a connection coupling 32, a readable and recordable information carrier 58, and a measuring point communication interface 56.

() recordable information carrier 58, and the measurement point communication interface 56 can be provided in a separate device 10 placed in the vicinity of pin 30, as illustrated in Figure 2.

In fact, the recordable information carrier 58, and the measuring point communication interface 56 can be provided within pin 30. This is described in more detail in WO 98 / 0L83I, the content of which is incorporated herein by reference.

System 2 is arranged to allow bidirectional communication between the communication measuring point interface 56 and the communication device communication interface 54, The measuring point communication interface 56 and the communication device communication interface 54 are preferably built to allow wireless communication. According to an embodiment, the measuring point communication interface and the communication interface of the analysis device have been constructed to communicate, one with. the other, by radio frequency (RF) signals. This embodiment includes an antenna at the interface of the communication measurement point 56 and a mild antenna at the communication interface 25 of the analyzer 54.

Figure 4 is a simplified illustration of an embodiment of memory 60 and its contents. The simplified illustration is intended to convey an understanding of the general idea of storing functions of different programs in memory 60, and is not necessarily a correct technical teaching of the way in which a program would be stored in an actual memory circuit. The first memory segment 70 stores program code to control the analyzer 14 to perform basic operations. Although the simplified illustration in Figure 4 shows a pseudocode, it should be understood that program code 80 can consist of machine code, or program code of any level that can be executed or interpreted by the data processing medium .50 (Fig.2A).

The second segment of memory 90, shown in Figure 4, stores a second set of program code 94, Program code 94, in segment 90, when executed on data processing medium 50, will cause the data analysis apparatus 14 perform a function, such as a digital signal processing function The function can comprise advanced mathematical processing of the digital measurement data signal According to embodiments of the invention, program code 94 is adapted to make the medium processor 50 performs signal processing functions described in connection with Figures 5, 6, 9 and / or Figure. 16, in this document.

As mentioned above in connection with Figure 1, a computer program to control the function of the analysis apparatus can be downloaded from the server computer 20. This means that the program to be downloaded is transmitted over a communications network 18. This can be done by modulating a carrier wave to transport the program over the communications network 18. In this way, the downloaded program can be loaded into digital memory, such as memory 60 (see Figures 2A and 4). In this way, a signal processing program 94 and or an analysis function program 164, 105 can be received through a communication port, such as port .16 (Figs. 1 and 2 A), in order to load them in memory 60. Likewise, a signal processing program 94 or an analysis function program 104, 105 can be received through the communication port 298 (Hg. I), in order to load them in a location program memory on computer 26B or database 22B. A specie of the invention relates to a computer program product, such as a program code medium 94 and / or program code means 104 »105 downloadable into a digital memory of an apparatus» The computer program product comprises portions of software code for carrying out signal processing methods and / or analysis functions when said product is executed in a data processing unit 50 of an apparatus to analyze the condition of a machine »The term '' executed in a data processing unit means that the computer program, plus the data processing unit, performs a method of the type described in this document.

The expression a computer program product, downloadable in a digital memory of a condition analysis device means that a computer program can be inserted into a digital memory of a condition analysis device, in order to obtain an analysis device condition programmed to be capable of, or adapted to, the realization of a method of the type described above. The term loaded into a digital memory of a condition analysis device means that the condition analysis device programmed in this way is capable of doing, or is adapted to carry out a method of the type described above.

The aforementioned computer program product can also be downloadable on computer-readable media, such as a compact disc or DVD. This computer-readable media can be used to dispense the program to a customer.

According to an embodiment of the analysis apparatus 14 (Figure 2A), it comprises a user interface input 1.02, through which an operator can interact with the analysis apparatus 1.4. According to one embodiment, the user input interface 102 comprises a set of buttons 104. An embodiment of the analysis apparatus 14 comprises a user exit interface 106. The user exit interface may comprise a display unit '106. The data processing medium 50, when executing a basic program function provided in the basic program code 80, provides interaction with the user through the user input interface 102 and the display unit 106. The set of buttons 104 can be limited to a few buttons, such as five buttons, as shown in Figure 2A. A central button 107 can be used for an ENTER or SELECT function, while other buttons, more peripheral, can be used to move a cursor over the display 106. In this way, it must be understood that symbols and text can be entered in the device 14 via of the user interface. Display unit 106 may, for example, display various symbols, such as the letters of the alphabet, while the cursor 6 is movable on the display, in response to user input, so as to allow the user to enter information.

Fin.ura 5 is a schematic block diagram of an embodiment of the analyzer 14 at a client location 4 with a machine 6 having a movable axis 8. (.> Sensor 10, which can be a measurement sensor for shock pulse, is shown attached to the machine body 6, in order to collect the mechanical vibrations and, in order to dispense an analog measurement signal S ^ a indicative of the detected mechanical vibrations one for the 40 interlace sensor. sensor 40 dispenses a data signal a digital measurement Smd for a medium 180 for digital signal processing.

The Smi digital measurement data signal? tetn a sampling frequency f _s and the amplitude range of each sample depends on the amplitude of the analogue measurement signal received $ s, x at the time of sampling. According to an embodiment, the sampling frequency f _s of the digital measurement data signal can be set to a determined value fi, such as, for example, k - 102,400Hz. The sampling frequency f $ can be controlled by a clock signal dispensed by a clock 190, as shown in Figure 5. The clock signal can also be dispensed for medium 180 for digital signal processing, Medium 180 for processing digital signal could provide information about the time duration of the received digital measurement data signal S.mu, in response to the digital measurement data signal S _M n received, the clock signal and the relationship between the sampling frequency and the clock signal, since the duration between two consecutive values of sample 10 is equal to T _s “M: L.

According to embodiments of the invention, the means 180 for processing digital signal includes one. preprocessor 200 for performing a pre-processing of digital measurement data signal in order to dispense preprocessed digital signal S _M ur for an output 210, The output 210 is coupled to an input 220 of an evaluator 230 The evaluator 230 is adapted to evaluate Smuix pre-processed digital signal in order to dispense an evaluation result for a user interface 106. Alternatively, the evaluation result can be dispensed for a communication port 16, in order to allow the transmission of the result, for example, to a control computer 33 at a control location 31 (See Figure 1).

According to an embodiment of the invention, the functions described in connection with the functional blocks in the medium 180 for digital signal processing, preprocessor 200 and evaluator 230 25 can be personified by computer program code 94 and / or 104, as described in connection with memory blocks 90 and 100, in connection with Figure 4 above.

A user may only need a few basic monitoring functions to detect whether the condition of a machine is normal or abnormal. When detecting an abnormal condition, the user can call specialist personnel, maintenance personnel, to establish the exact nature of the problem. , and to perform the necessary maintenance work. Professional maintenance personnel often need and use a wide range of evaluation functions to provide an opportunity to establish the nature and / or reason for an abnormal condition of the machine. In this way, different users of an analysis device 14 can place very different demands on the function of the device. The term Condition monitoring function is used throughout this document to detect whether the condition of a machine is normal or slightly deteriorated or abnormal. The term Condition monitoring function also comprises an evaluation function providing to establish the possible nature and / or the reason for an abnormal condition of the machine.

Examples of machine condition monitoring functions

The condition monitoring functions Fl, F2, ..., Fn include functions such as: vibration analysis, temperature analysis, shock pulse measurement, spectral analysis of shock pulse measurement data. Fast Fourier transform of vibration measurement data, graphical presentation of condition data on a user interface, storage of condition data on a recordable information carrier on the aforementioned machine, condition data storage on a recordable information carrier on the mentioned apparatus, tachornetry, detection of imbalance, and detection of deflection.

According to an embodiment, the apparatus 14 includes the following functions. '

F1 vibration analysis;

F2 “temperature analysis,

F3 measurement of ehuque pulse.

F4 spectrum analysis of shock pulse measurement data.

F5 ' ^::: Fast Fourier transform of vibration measurement data,

F6 ™ graphical presentation of condition data on a user interface *

F7 storage of condition data in a recordable information carrier 5 about the mentioned machine.

F8 ~ storage of condition data in a recordable information carrier 52 in said device *

F9 - · t.acometry

Wire imbalance detection, and

() F i 1 ”detection of de-alignment,

F12 - Recovery of condition data from a recordable information carrier 58 about the mentioned machine.

ΙΊ3 Realization of the F1 vibration analysis function and realization of the Fl 2 function. Recovery of condition data from a recordable information carrier 15 on the mentioned one, machine in order to allow a comparison or trend based on current vibration measurement data. and historical vibration measurement data.

F14 ~ Conducting temperature analysis F2 and performing the function Retrieving condition data from a recordable information carrier 20 58 on the aforementioned machine in order to allow a comparison or trend based on current temperature measurement data and measurement data historical temperature ranges.

F15 Retrieval of identification data from a recordable information carrier 58 about the mentioned machine.

2>. Methods of carrying out the function F7 '' condition data storage in. a recordable information carrier. about the mentioned machine, and F13 vibration analysis and condition data recovery are described in more detail in WO 98 / 01.831, the content of which is incorporated herein by reference.

6 Figure 6 illustrates a schematic block diagram of an embodiment of the preprocessed (jr 200, according to an embodiment of the present invention. In this embodiment, the digital measurement data signal is coupled to a filter digital bandpass 240 having a lower cutoff frequency ffc, an upper cutoff frequency f _V e and bandpass bandwidth between the upper and lower cutoff frequencies.

The output of the digital bandpass filter 240 is connected to a digital envelope 250. According to an embodiment of the invention, the output signal from the envelope 250 is dispensed for an output, 26 () ,. Is output 260 10 of preprocessor 200 coupled to output 210 of the middle? digital signal processing 180 for dispensing to input 220 of evaluator 230.

The upper and lower cut-off frequencies of the digital passband filter 240 can be selected so that the frequency components of the Smd signal at the resonance frequency G _.; m for sensor 15 are in the bandpass bandwidth. As mentioned above, an amplification of the mechanical vibration is obtained by the mechanically resonant sensor, at the resonance frequency Γ ^ μ »In this way, the analog measurement signal Sr .; _A reflects an amplified value of vibrations at and around the resonance frequency Consequently, the bandpass filter, according to the embodiment of Figure 6, advantageously suppresses the signal at frequencies below and above the resonance frequency in order to further intensify the components of the measurement signal at the resonance frequency f _RM <Akòn addition, the digital bandpass filter 240 advantageously reduces even more the noise inherently included in the measurement signal, since any noise components below the lower cut-off frequency and above the upper cut-off frequency fi _{; {:} are also eliminated or reduced. Thus, when using a shock pulse resonance measurement sensor 10 having a mechanical resonance frequency f _RM in a range of a lower resonance frequency value

Λ / f _RM1 until a higher resonance frequency value Ir ^ ·. Digital bandpass fdh'o ⁰ 240 could be designed to have a frequency enjoys Interim ^'fu:: ··' · Írmu and "ma upper cut frequency fi _c - Guam According to one embodiment, the cutoff frequency lower fi. <: ^:::: Írml ™ · 28kHz and the upper cut-off frequency Πχ · ~ Í rmu ^::: 37kHz.

According to another embodiment, the mechanical resonance frequency f _RM is somewhere in the range of 30kHz to 35kHz, and the digital bandpass filter 240 can then be designed to have an internal cutoff frequency f _c “ “30kHz and a higher tan frequency _f = _c ~ 35kHz.

According to another mute, the digital bandpass filter 240 can be designed to have a lower cutoff frequency q..c lower than the lowest resonance frequency value and a higher cutoff frequency fi _; . _c being greater than the highest resonance irequence value ί | < _Μ , For example, the mechanical resonance frequency Irm can be a frequency in the range 30kHz to 35kHz, and the digital baud filter 240 can be designed to have a lower cut-off frequency fi, c ™ 17kHz. is. upper cutoff frequency fix · ““ 36kHz.

From that mute, the digital bandpass filter 240 dispenses a digital bandpass measurement data signal Sp having an advantageously low noise content and reflecting mechanical vibrations in the bandpass. The digital bandpass measurement data signal Sp is dispensed to the 250 envelope.

The digital envelope 250, consequently, receives the digital bandpass measurement data signal which can reflect a signal having positive as well as negative amplitudes. With reference to Figure 6, the received signal is rectified by a digital reticifier 270, and the rectified signal can be filtered by an upcipel low-pass filter 280, in order to produce a digital envelope signal Sfw

Consequently, the signal is a digital representation of an envelope signal to be produced in response to the filtered measurement data signal Sp. According to some embodiments of the invention, the optional low-pass filter 280 can be eliminated. Such an embodiment is explained in connection with Figure 9 below. Therefore, the low-pass filter. option 280, in the envelope 250 it can be eliminated when the decimator 310, explained in connection with Figure 9 below, includes a low-pass function.

According to the embodiment of the invention of Fig. 6 the Sinai Sf-.Nv is dispensed for output 260 of preprocessor 200. Thus, according to an embodiment of the invention, the preprocessed digital signal S _M nr dispensed by output 210 (Fig, 5) is the Senv digital envelope signal. While the prior art analog devices for generating an envelope signal in response to a measurement signal use an analog rectifier that inherently leads to a bias error introduced in the resulting signal, the digital envelope 250 will advantageously produce a true rectification without bias errors. Consequently, the digital envelope signal has a good signal-to-noise ratio, since the sensor, being mechanically resonant in the resonance frequency in the bandpass of the digital bandpass filter 240, leads to a high signal amplitude and processing signal being performed in the digital domain eliminates the addition of noise and eliminates the addition of bias errors. With reference to Figure 5, the preprocessed digital signal Smof is dispensed for input 220 of evaluator 230.

According to another embodiment, filter 240 is a high-pass filter having a cutoff frequency ffr. This embodiment simplifies the project, replacing the bandpass filter with a 2-W high-pass filter, thereby leaving the low-pass filter for another downstream low-pass filter, such as the 280 low-pass filter. cut-off frequency of the pass-through filter aha 240 is selected for approximately the lowest value expected mechanical resonance frequency value f _KM1 , from the resonance shock pulse measurement sensor 10. When the mechanical resonance frequency Ir is somewhere in the range from 30kHz to 35kHz. the high pass filter 240 could be designed to have a lower cutoff frequency fet - 30kHz. The filtered pass-through signal is then passed to rectifier 270 and through the low-pass filter 28 (λ According to one embodiment it would be possible to use sensors 10 having a resonance frequency somewhere in the range of 20kHz to 35 kHz. to achieve this, the high-pass filter 240 can be designed to have a lower frequency fl ernie. _<? 20kHz.

Figure 7 illustrates an embodiment of evaluator 230 (see also Fig. S i. (.) Embodiment of evaluator 230 of Figure 7 includes a condition analyzer 290 adapted to receive a pre-processed digital signal indicative of the condition of the machine 6. The condition analyzer 290 can be controlled to perform a selected condition analysis function by means of a selection signal dispensed for, a control input 300. The selection signal dispensed for control input 390 can be generated through user interaction with user interface 102 (see Figure 2A) .When the selected analysis function includes Fast Fourier Transform, the analyzer 290 will be established by the selection signal 300 to operate on an input signal in the domain frequency.

Depending on the type of analysis to be performed, the conditioner 290 can operate on a pre-processed digital input signal Smup in the time domain, or on a pre-processed digital signal S _M ne in a frequency domain. Consequently, depending on the selection signal dispensed for control input 300. a 1 Wire 294 can be included, as shown in Figure 8. or the signal can be dispensed directly to the 290 analyzer, as shown in Figure 7.

Figure 8 illustrates another embodiment of evaluator 230. In the embodiment of Figure 8, evaluator 230 includes an optional Fast Fourier Transform 294 coupled to receive the signal from input 220 of evaluator 230, The output of the FF transformer 2.94 can be dispensed with for the 290 analyzer.

In order to analyze the condition of a rotating part, it is desired to monitor the vibrations detected for a sufficiently long time to be able to detect repetitive signals. Certain repetitive signal signatures are indicative of a deteriorated condition of the rotating part. An analysis of a repetitive signature signal can also be indicative of the deteriorated condition tie type. This analysis can also result in the detection of the degree of the condition if deteriorated.

In this way, the measurement signal can include at least one vibration signal component S:> dependent on a vibration movement of the rotatingly mobile part 8; where the said vibration signal component has a repetition frequency f _t > which depends on the rotation speed fkyr of the rotatingly moving part 8. A. vibration signal component, which is dependent on the vibration movement of the rotatingly moving part 8, it can therefore be indicative of a deteriorated condition or damage to the monitored machine. In fact, a relationship between repetition frequency 1T of the vibration signal component S:> and the rotation speed f _Ror of the rotatingly moving part 8 can be indicative of which mechanical part has a damage. In this way, in a machine having a plurality of rotating parts »it could be possible to identify an individual part that was damaged by processing the measurement signal using an analysis function 105, including a frequency analysis.

This frequency analysis can include Fast Fourier Transform of the measurement signal, including the vibration signal component S _; >. Λ Fast Fourier transform (FFTp uses a determined frequency resolution, This determined frequency resolution, which can be expressed in terms of frequency sections, determines the limit for discerning different frequencies. The term '' frequency sections '' è sometimes referred to as''lines.' If a frequency resolution is desired providing Z frequency sections up to the axis speed, then it is necessary to record the si uai during X axis revolutions.

In connection with the analysis of rotating parts it may be interesting to analyze signal frequencies that seal higher than the frequency of rotation of the rotating part. The rotating part may include a shaft and bearings. The frequency of rotation of the frcn axis is often referred to as '' order Γ. Interesting bearing signals can occur about ten times per revolution of etxo (Order 10). that is, a damage frequency f ₅₎ (measured in Hz) divided by the flotation rotation speed (measured in rps) equal to ÍOHzÃps, that is, order y ^:::: WfRor ~ 10Hz / rps. In addition, it may be interesting to analyze overtones of the bearing signals, since it may be interesting to measure up to order 10 (1. With reference to a maximum order Y, and the total number of frequency sections in the FFT to be used as Z, the following is applicable: Z ™ X * Y. In contrast, X ·· ΖΛ \ where

X is the number of rotations of the monitored axis during which the digital signal is analyzed, and ¥ is a maximum order, and

Z and the frequency resolution expressed as a number of frequency sections

Consider a case where the digitized measurement signal (see Figure 5) is dispensed for the FFT 294 analyzer, as described in Figure S: In this case, when the FFT 294 analyzer is set for Z - 1600 frequency sections and the user is interested in analyzing frequencies up to the order Y 100, then the value of X is provided X - Z / Y -1600 / 100-16.

Thus, it is necessary to measure during X ™ 16 revolutions of erw when Z ··· 1,600 frequency sections is desired and that user 5 is interested in analyzing frequencies up to the order ¥ ···· l00.

The Z frequency resolution of the 1TT 294 analyzer can be adjusted using the user interface 102, .106 (Fig, 2 A).

In this way, the Z frequency resolution value for condition analysis function 105 and / or for signal processing function 94 (Fig. 4) can be adjusted using the user interface .102, 106 ( FB2AX

According to an embodiment of the invention, the ................. .... ............ ...

Z frequency resolution is adjustable by selecting a Z value from a group of values. The group of selectable values for the Z frequency 15 resolution can include

Z ·· 400

Z - 800 z 1600

Z - 3200

Z - 6400

As mentioned above, the sampling frequency. f _s can be sanded to a specified value, such as f _s ··· 102,400kHz. and the k factor can be set to 2.56, thereby providing the maximum frequency to be analyzed

- 102,400 / 2.56 - 40kHz

For a machine having an axis with a rotational speed of 1.715rpm 28.58rps, a selected order value Y ™ 100 provides a maximum frequency to be analyzed

1W * Y - 28.58rps * 100 - 2,858Hz.

The FF 2.94 transformer can be adapted to perform the Fast Fourier Transform on an input signal received having a certain number of sample values. It is advantageous when the given number of sample values is defined as an even integer, 5 that it can be divided by two (2) without resulting in a fractional number. Consequently, a data signal that represents mechanical vibrations emanating from the rotation of an axis can include repetitive signal patterns. A given signal pattern can thus be repeated a number of times per revolution of the axis being monitored. In addition, repetitive signals can occur with mutually different repetition frequencies.

Machinery 'Vibration Measurements and Analysis by Victor Wowk (ISBN 04) 74) 71936-5), In the book Machinery Vibration Measurements and Analysis ”by Victor Wowk (ISBN 04) 7-071936-5), a pair of 15 examples of mutually different repetition frequencies on page 149;

Fundamental train frequency (FTF} ”ball turn frequency (BS) pi sta and xtern a (OR) inner track (IR)

The book also provides formulas for calculating these specific frequencies on page 150. The content of the book Machinery Vibration Measurements and .Analysis, by Victor Wowk, is incorporated here, by reference. In particular, the aforementioned formulas for calculating these specific frequencies are hereby incorporated by reference.

A table on page 151 of the same book indicates that these frequencies also vary depending on the manufacturer of the manual, and that

FTF can have a 0.38 bearing frequency fector;

BS can have a bearing frequency factor of 1.928;

OR can have a bearing frequency factor of 3.024. and

IR can read a bearing frequency factor of 4,976.

The frequency factor is multiplied by the speed of rotation of the axis to obtain the repetition frequency. The book indicates that an axis with a rotation speed of 1.7 l5 rpm, that is, 28 _f 58 ilz, 5 the repetition frequency for a pulse emanating from the external track (OR) of a bearing of the standard type 6311 can be of approximately S6Hz; and the FTF repetition frequency could be 10.8.Hz.

When the monitored axis rotates at a constant speed of rotation, this repetition frequency can be explained in terms of 10 repetitions per unit of time, or in terms of repetition per rotation of the axis being monitored, without distinguishing between the two. However, if the machine part rotates at a variable speed of rotation the issue is even more complicated, as explained below in connection with. Figures 16, 17 and 20.

Machinery showing sudden damage

IS Some types of machinery can fail completely or break machine very abruptly. For some types of machines, such as rotating parts in a wind power station, it is known that the breakdown occurs suddenly and as a complete surprise to maintenance personnel and the machine owner. This breakdown will rise, cause a series of costs for the machine owner and can cause other negative side effects, for example »if parts of the machine come off as a result of unexpected mechanical carving.

It has been noticed that there is a particularly high level of noise in the mechanical vibrations of some machines, and that these noise levels 25 make it difficult to detect damage to the machine. Thus, for some machinery units, conventional methods for preventive condition monitoring have failed to provide sufficiently early and / or reliable warning of deteriorating conditions that may occur. It was noted that there was a mechanical vibration that could indicate a deteriorated condition in these machines, but that conventional methods for measuring vibrations may, until then, have been inadequate.

Machines with slow-moving parts were found to be among the types of machines that seem particularly prone to sudden failure. It was also realized · that a low rotation speed f ^ y can lead to smaller amplitudes of the mechanical vibration V _M q. When the mechanical vibration indicative of Incipient damage to the machine has a low amplitude, the noise content in the measurement signal will be higher in relative terms. When measuring on a machine with a speed of 10 revolutions below 50 rpm, the digital measuring signal enveloped and output Siuu >> dispensed by the decimator 310. can be so noisy as to prevent the successful monitoring analysis if the Decimated digital measurement Sr ^ .u is fed directly to analyzer 290. In other words, the signal-to-noise ratio, SNR, of the decimated digital measurement signal 15 Srhj can be so low as to prevent the detection of any signal component of vibration S _D.

Having realized that a paniculously high noise level in the mechanical vibrations of some machines makes it difficult to detect damage to the machine, a method has emerged to allow the detection of weak mechanical signals in a noisy environment. As mentioned above, the repetition frequency f ^ of the vibration signal component So in a noisy measurement signal depends on a mechanical vibration V _M u. indicative of incipient damage to a rotating part 8 of the monitored machine 6. It has been realized that it may be possible to detect incipient damage, that is, damage 25 that is just beginning to develop if a corresponding weak signal can be discerned.

In this way, the measurement signal was able to include at least one vibration signal component dependent on a vibration movement of the rotatable mobile part 8; where the aforementioned vibration signal component has a repetition frequency that depends on the rotation speed t ^ »> r rotatingly mobile purle 8. The existence of a vibration signal component dependent on the vibration movement of the rotatingly moving part 08 can * therefore, provide an early indication of a deteriorating condition or incipient damage to the monitored machine.

In a wind turbine application, the shaft, whose bearing is analyzed * can rotate at a speed of less than .120 revolutions per minute * meaning that the axis rotation frequency is less than 2 revolutions per second (rps), Some times, this axis to be analyzed rotates at a speed less than 50 revolutions per minute (rpm.) * that is, with a rotation frequency of less than (), S3rps. In fact, the speed of rotation can normally be within I5rpm, while an axis with a speed of rotation of I.7J5rpm, as discussed in the aforementioned book * produces 500 revolutions in just 17.5 seconds; a rotation axis of 50 revolutions per minute takes 10 minutes to produce 500 revolutions. Certain large wind power plants have shafts that can normally run at 12rpm ~ 0.2rps.

Consequently * when a bearing to be analyzed is associated with a slow rotation exxo and the bearing is monitored by a detector generating an analog measurement signal Sha sampled using a sampling frequency of about 10 Okhz * the number of sampled values associated a complete revolution of the axis is too large. As an illustrative example, 60 million values of sample are required (60,000.0 (10), at a sampling frequency of 100kHz, to describe 500 revolutions when the axis rotates at 50rp. m.

In addition, conducting advanced mathematical analyzes of:: .............::::: .......::::::::: <<String> . ::: .......::: ........:::::::::::::::::: <: <:: ...... : ......:

signal requires a lot of time when the signal includes so many samples. It is therefore desired to reduce the number of samples per second before further processing the $ e \ v signal.

Figure 9 illustrates another embodiment of the preprocessor 200. The embodiment of the preprocessor 200 of Figure 9 includes a digital bandpass filter 240 and a digital wrapper 250, 5 as described above in relation to Figure 6. As mentioned above, the signal S ^ xv is a digital representation of an enveloped signal produced in response to the filtered measurement data signal Sp

According to the embodiment of the preprocessor 200 of Figure 9, the digital enveloped signal Sesív is dispensed to a decimator 10 310 adapted to produce a digital signal S _REn having a reduced sampling frequency Decamer 310 operates to produce a signal digital output where the time duration between two consecutive sample values is greater than the time duration between two consecutive sample values in the input signal. The decliner is described in more detail in relation to Figure 14, below. According to an embodiment of the invention, the optional low-pass filter 280 can be eliminated, as mentioned above. Qt.ia.ndo, in the embodiment of Figure 9, the signal produced by digital rally 270 is dispensed for decliner 310, which includes low-pass filtering, the low-pass filter 280 can be eliminated.

An output 312 of decimator 310 dispenses the digital signal to an input 315 of an intensifier 320. The intensified? ' 320 is capable of receiving the digital signal S _RE n in response to it, generating an output signal The output signal is dispensed to the output port 260 of the preprocessor 200.

Figure I0A is a flowchart that illustrates embodiments of a method for enhancing repetitive signal patterns in signals. This method can be used advantageously to intensify repetitive signal patterns in signals that represent the condition of a machine having a rotation axis. An intensifier 320 can be designed to operate according to the method illustrated in Figure 10Λ »

The steps of the SIO0O to SI040 method, in Figure 10A, represent preparatory actions to be taken in order to make adjustments before actually generating the output signal values »When the preparatory actions 3 have been performed, the signal values of output can be calculated as described with reference to step SI050 »

Figure 10.B is a flow chart. illustrating a method of generating a digital output signal More particularly, Figure 10B illustrates an embodiment of a method for generating a digital output signal when the 10 preparatory actions described with reference to steps S1000 to SI 040. in Figure 10A, have been carried out.

With reference to step S1000, in Figure 10A, a desired length OeoMraiMt-.mO 9e and an output signal is determined.

Λ Figure 11 is a schematic illustration of a first memory having several memory locations i. The memory positions 1 of the first memory contain an example of an input signal I comprising a sequence of digital values. The example of an input signal is used to calculate the Smvp output signal according to embodiments of the invention. Figure 11 shows some of the many consecutive digital values for input signal I, Digital values 2080 in input signal I illustrate only some of the digital values that are present in the input signal. In figure 11, two neighboring digital values, in the input signal, are separated by a duration t ^ _{} u <} The value t ^ is the inverse of a frequency

2.5 Fig. 9 and sampling of the input signal received by the intensifier 320 (see Fig. 16).

Figure 12 is a schematic illustration of a second memory with several memory locations L The memory locations t. from the second memory, it contains an example of an S _MDP output signal comprising a sequence of digital values. Thus, Figure 12 illustrates a portion of a memory reading value ?; digital 3090 stored in consecutive memory locations. Figure 12 shows consecutive digital values for the output signal. The digital values 3090, as the output signal. illustrate only some of the digital values that are present in the output signal. In figure 12, two neighboring digital values, in the output signal, can be separated temporarily by the duration.

With reference to the SIOOO step, in Figure 10, the desired length Ο <'ομρ «ιμι · χ ^: ι · ο 3010 of the Smup output signal can be chosen so as to. it is possible to use the output site for the analysis of certain frequencies in the output signal. If, for example, lower frequencies are of interest, a longer output signal is needed than when higher frequencies are of interest. The lowest frequency that can be analyzed using the output signal is Ι / (0 {: <> μριομε \ · ο * WÁ where Ocomprimentu is the number of sample values in the output signal. If f _SR out sample rate of the input signal I, then the time t ^ a between each digital sample value will be 1 / fs ^ As mentioned above, repetitive signal patterns can occur in a data signal representing mechanical vibrations. Consequently, a measurement signal, such as the signal _{SÍ; NA} · dispensed by the envelope 250 and the signal S _RE u, dispensed for the intensifier 320, can include at least one component of the vibration signal A> dependent on a vibration movement of the retail mobile part 8; mentioned vibration signal component Sn t «m a repetition frequency fp that depends on the rotation speed of the rotatingly movable part 8. So, to be sure to detect the occurrence of a repetitive signal pattern with a frequency the repetition ^:::: · the output signal must include at least OaiMPRiMcmo digital values »when consecutive digital values at site output 8 ^ ·· ^ are separated by the duration t ^.

According to an embodiment, the user can enter a value that represents the lowest repetition frequency to be detected, as well as information about the lowest expected rotation speed of the axis to be monitored, The analysis system 2 (Figure Π includes functionality to calculate a suitable value for the variable in response to those values. Alternatively, with reference to Figure 2Λ, a user of an analyzer 14 can set the value of 0 <owkjmi; n 3010 of the output signal S _{Mb {} . <by entering a corresponding value via user interface 102 ..

In a next step 81010, a length factor of L is chosen. The length factor L determines how well the esrochastic signals are suppressed at the Smop signal output. A higher value of L provides less stochastic signals at the output signal S ^ _i5 p than a smaller value of I ... Thus, the length factor L can be referred to as an incremental value of the Smal-Noise Ratio, also known as an S.NR incremental value. According to an embodiment of the method, I, is an integer between l and 10, but 1. can also be defined for other values. According to a method realization method, the L value can be predefined in intensifier 320. According to another method realization, the L value is entered by a method user through the user interface 102 (Fig. 2A). The value of factor L also has an impact on the calculation time required to calculate the output signal. A higher value of L requires more calculation time than a lower value of 1 ...,.

Then, in a step S1020, is set one (xtsição departida _ro. The starting position S _K OLS may indicate a position on the input signal. 1

The start position S ^ tao is defined to prevent or reduce the occurrence of non-repetitive patterns in the output signal S ^ laugh- When the start position is defined so that a part 2070 of the input signal before the start position line mn compliance that corresponds to a determined time interval T ^ cuastic max, then stoic signals with the corresponding frequency Ístgchasuo max and higher frequencies will be attenuated in the output signal SmupIn a next step SI030, the required length of the data signal is calculated input. The required length of the input data signal is calculated in step SI 030, according to formula (I) below:

l 1) OcOMPRLMEN FOUNDATION * 1- ⁴ 'S -r OcOMFRiMENT

Then, in a step S 1040, an input data signal length is calculated. The length of the length is the length over which the output data signal is calculated. This Ccomprimenh length. » is calculated according to formula (3) below.

(3) (. KoMPRjMEUrCí SiNlOJO 'UcUMPRIMÍRUO LENGTH

Λ formula (3) can also be written as Içomhumenio ^{:: t:} CoôMFRtMhNm S-MCÍO '·' θ CUMPRÍMÍ Nm

The output signal is then calculated in a SI050 step. The output signal is calculated according to the formula (5) below. In formula (5) a value for the output signal is calculated for a time value í in the output signal.

15) SMIÍPft) V * / tí} * // <* '“.Ç / vx omA? / 5. / S Dvuu.osmvuvía

The output signal S _MDP has a length On mm in o, as mentioned above. To acquire all 0 output signal S _MDP , a value for each, time value, from t '1 to ^; Ο «> μρ donkey, has to be calculated with the formula (5). In Figure 11, a digital value 2081 illustrates a digital value that is used in calculating the output signal. Digital value 2081 illustrates a digital value that is used in calculating the output signal, where i I, Digital value 2082 illustrates another digital value that is used in calculating the output signal. The reference numeral 2082 refers to the value l (I ·? S ^ icto * D u the formula (5) above, when i - 1 and t - I. Thus, reference numeral 2082 illustrates the digital sample value in the position number P in the input signal:

In figure 12, reference numeral 3091 refers to the digital sample value SmoKÕ in the output signal, where t ~ 1.

A further embodiment of the method for operating intensifier 320 to intensify repetitive patterns in signals that represent the condition of a machine having a rotary axis will now be described. According to one embodiment, the OeoMPRiMENto length can be predefined in the immensifier 320. According to other method embodiments, the length Ο <χ) μνομρν · ιό can be defined by the user input via the user interface 102 (Fig. 2 A). According to a preferred embodiment of the method the variable Ocomprimexuo is defined for an even integer that can be divided by two (2), without resulting in a fractional number. The selection of the Oc <mpRtMt-: sm> variable according to this rule, advantageously adapts the number of samples in the output signal so that it is suitable for use in the optional Fast Fourier Transform 294. Thus, according to modes When carrying out the method, the variable 0 <x ₅ mprímsxto can be defined, preferably, for some numbers, for example, 1024, 2048, 4096.

In a particularly advantageous embodiment the value Srslao is defined in step SI 020, so that part 2070 of the input signal before the. start position has the same length as the exit signal 3940. ie Siníctn · ^:::: Dcumprísu-.n

As mentioned in connection with equation (l) above, the required length of the input data signal is 1 <. · ΟΜΡΝίΜ: \ ί »> θ <OMHUMh:, · U? * 1 '' Dí> m? R: M}? UO

Thus, the definition of SiMeso ·· 'ua eq. (1) provides k'uortuse w Ou.miwmkio * t O _s > * · Ocooriuur.cm OFOMPRlMENT * I * O <X) SmUMF.NIO * 2 5 Consequently, the required length of the input signal can be expressed in terms of the length of the output signal of

according to equation (6) goes down.

{61 If <t \ í {»' ₅ <ÍMV \'U> (J- ~ '2) * í VoMPRlMENT where L is the length factor explained above, and

Qckimwmeuto is the number of digital values in the output signal, as explained above.

The length of the length P 'must be calculated, in this embodiment of the invention, according to the formula (7) below.

(7) CeaM ^ rImENT 1- * Hi-omprimexio

When the preparatory actions described with reference to the steps

SIOO to SI040, in Figure I0A have been carried out, the digital output signal can be generated by means of a method described with reference to Figure 10B. According to an embodiment of the invention, the method described with reference to Figure 10B is carried out by means of a DSP 50 (Figure. 2A).

In a SHOO stage (Figure 10B), the 320 will receive one. digital input signal I having a first plurality of sample values on an input 315 (see Figure 9 and / or Figure, 16). As noted above, the digital input signal I can represent mechanical vibrations emanating from the rotation of an axis in order to cause a vibration to occur by reading a repetition period T _R

The received signal values are stored (step SH20) in an input signal storage portion of a data memory associated with the inensifier 320. According to an embodiment of the invention, the data memory can be personified by the memory memory read-write 52 (Figure 2.Λ).

In an SI 130 step, the variable t, used in equation (5) above, is defined as an initial value. The Initial value can be I (uml

In step Si 140, an output sample value S ^ Rt) is calculated for the sample number t The calculation can use the equation below:

The resulting SMoriO sample value is stored (step SU50, Figure 10B) in a memory output signal storage portion 52 (see Figure 12).

In a step Sl 160, the process checks the value of variable t, and if the value of t represents a number less than the desired number of output sample values OcoMFtUMExrrm step S 1160 is performed to increase the value of variable t before repeating steps S1140, SI 150 and SI 160.

If, in step S1160, the value of t represents a number equal to the desired number of output sample values Ooomprímenjo, step SI 180 is performed.

In step SllRO, the output signal O, Smd? is dispensed by outlet 260 (see Figure 9 and / or Figure 16). As mentioned above, a data signal representing mechanical vibrations emanating from the rotation of an axis can include repeatable signal signatures, and a given signal signature can thus be repeated a number of times per revolution of the axis that is being monitored. In addition, several mutually different repetitive signal signatures may occur, where mutually different repetitive signal signatures may have mutually different repetition frequencies ... The method for intensifying repetitive signal signatures on signals, as described above, allows, advantageously, the simultaneous detection of many repetitive site signatures having mutually different repetition frequencies, this advantageously allows the simultaneous detection of. for example, a Track damage signature

Internal bearing and a signature of External bearing damage in a single measurement and analysis session, as described below.

Λ Figure 13 is a schematic illustration of an example of an Smdp output signal comprising two repetitive signal signatures 401o and 4020. The Smdp output signal may comprise more repetitive signal signatures than shown in the Figure. 13, but for illustrative purposes only, only two repetitive signal signatures are shown. Only a few of the many digital values for 4010 and 4020 repetitive signal signatures are shown in Figure 13.

In Figure 13, an External Track frequency signal (OR) 4020 and the Track frequency signal. Internal (IR) 4010 are illustrated, As can be seen in Figure 13, the External Track (OR) frequency signal 4020 has an ink frequency lower than the Internal Track (IR) frequency signal 4010, The repetition frequency for the external track frequency signal COR) 4020 and the internal track frequency signal (IR) 4010 are el / l'fr>, respectively.

In the embodiments described above of the intensifier operation method 320 to intensify repetitive signal patterns, the repetitive signal patterns are amplified when calculating the output signal in step SI050. A greater amplification of the repetitive signal patterns is obtained if the factor L is given a higher value in step S1011L than if the value L is given a lower value. A higher value of L means that a longer input signal longer is required in step SI030. A longer input signal longer therefore results in a greater amplification of the repetitive signal patterns in the output signal. Thus, a longer average input signal provides the effect of better attenuation of stochastic signals over repetitive signal patterns in the output signal.

According to an embodiment of the invention, the whole value knvpRjMEmo can be selected in response to the desired frequency of attenuation of stochastic signals. In an embodiment of this type, the length factor L can be determined depending on the selected whole value. Icomprímentc5 Now consider an exemplary embodiment of the method to operate the intensifier 320 to intensify repetitive signal patterns, where the method is used to the amplification of a repetitive signal pattern with the lowest determined frequency. In order to be able to analyze the repetitive signal pattern at the lowest determined frequency, a determined length of the output signal is required.

As mentioned above, using a longer input signal in calculating the output signal results in the repetitive signal pattern being more amplified than if a smaller input signal is used. If a determined amplification of the repetitive signal pattern 15 is necessary, it is therefore possible to use a determined length of the input signal in order to obtain this determined amplification of the repetitive signal pattern.

To illustrate the aforementioned embodiment, consider the following example:

A repetitive si.na1 pattern with the lowest repetition frequency is of interest. In order to ensure the detection of this repetitive signal, it will be necessary to produce an output signal capable of indicating a complete cycle, that is, it needs to represent a tie duration Τι ^: · bT'r When consecutive output signal sample values are separated for a sampling period L _k . _Ua , the minimum number of sample values in the output signal will be Οοομ ^ μεοτο ^ “D / D ,; _{; 3} .

As mentioned above, the amount of amplification of the repetitive signal will increase with the length of the signal! input.

i.'as mentioned above, the method described with reference to

Figures 10 to 13 above, operate to immense repetitive signal signatures in a sequence of measurement data emanating from an axis of rotation. The term repetitive signal signature should be understood as sample values | x (t), xft · * T), x (tt · 2T), x (í + nT)], including an amplitude component having a value of non-stochastic amplitude and where a duration T. between these sample values is constant while the axis rotates at a constant speed of rotation. With reference to Figure 13 * it should be understood that digital values 40.1 ü result from the highlighting of several repetitive signal values in the input signal 1 (see Figure 1l) * where the values of the 10 input signal are separated in time by a duration T _5f <. Thus.

in this case * it can be deduced that the repetitive signal signature refers to a damage to the inner ring of the bearing assembly * when the repetition period corresponds to a speed of passage of the ball in the inner ring. Naturally, this presupposes knowledge of the shaft diameter and the speed of rotation. In addition, when there is this repetitive signal signature component * there may be a repetitive signal component value x, so that x (t) has an amplitude similar to x (tt T), which has a similar amplitude to x (t * 2T) * which has a similar amplitude to x (t * nT) x, and so on. When there is this repetitive signal signature 20 present in the input signal, it can be potentially detected using the method described above, even when the repetitive signal signature is so weak as to generate a component of less amplitude than that of the stochastic signal components,

The method described in connection with Figures 10-13 can be performed by the analysis apparatus 14 when processor 50 executes the corresponding program code 94, as explained in conjunction with Figure 4, above. The data processor 50 may include a central processing unit to control the operation of the analysis apparatus 14, as well as a Digital Signal Processor (DSP). The DSP can be arranged to actually run program code 90 to cause the andhse apparatus 14 to execute program 94 causing the process described above in connection with Figures 1 () - 13 to be executed. The Digital Signal Processor can be, for example, type TMS3.20C6722, manufactured by Texas Instruments. In this way the analyzer 14 can operate to perform all signal processing purposes 94, including filtering function 240, enveloping function 250, decimation resolution 310 & 470 and intensification function 320.

According to another embodiment of the invention, signal processing can be shared between the apparatus .14 and the computer 33. as mentioned above. In this way, the apparatus 14 can receive the analog measurement signal Sc _A and generate a corresponding digital signal S _MD and then dispense with the digital signal S _M «the control computer 33, allowing additional signal processing functions 94 carried out at the control location 31.

Figure 10C illustrates an embodiment of intensifier 320. The auto-sensifier 320 has an input 315 on which it can receive a digital signal S _RKD having a sample rate f ke?>.

Intensifier 320 may include a signal handler 325 adapted to receive the digital signal at a port 326. Signal handler 325 also includes a port 327 to receive a control value indicative of the desired length I _and shortening the input signal. 1.

The miensifkador 320 can also include a parameter setting means 330. The parameter setting means 330 operates to generate control values relevant to the execution of the desired signal enhancement. In this way, the parameter setting means 330 has an output 332 to dispense the control value Ιοομρκιμγν-ο for the handler of • 5 · Ύ · * ί> s' * to signal 2.?.

The intensifier 320 can receive definition instructions through inputs 335. The definition instructions received through inputs 335 can include data indicating a value of order Y, data indicating a resolution of frequency Z, and data indicating an inherent value of SNR, L. Inputs 335 can be coupled to 5 dispense the received data for the parameter setting medium 330 (see Fig. IOC) ,.

The intensifier 320 can be integrated into an analysis apparatus 14, as described above, for example, with reference to Figure 1,

Alternatively, the intensifier 320 can be a part of the computation ?: of control 33 in the central control location 31 (see Fig. I),

Consequently, the digital signal having a sample rate f _s xrm can be dispensed to the control computer 33 via port 29B, for example, of the analysis apparatus 14, via communications network 18.

I. Figure I.OD illustrates signals according to an embodiment of the intensifier method. A digital input signal 1, having a sample rate is illustrated schematically at the top of Figure 10D. The digital input signal I includes at least sample values, where kvwRtMENio is a positive integer mn.

The execution of a calculation, as described by equation (5) above, can be illustrated as an operation involving a first portion of signal S1 and a second portion of signal S2.

The first portion of signal S1 includes a copy of the first sample values $ 0- in the input signal I. Sn .. 'Icomfrlmento ~ UCOMPRIMENTO25 The second portion of signal S2 includes a copy of the last sample values S ^. input signal L 5Q. ™ IcoMvsuMsmn ~ S ^ àio ·

The sign 0 =, 1, at the bottom of Figure 10D. is a schematic illustration of an output signal O _S5 obtained in response to a calculation involving the first portion of signal S1 and the second portion of signal S2.

Figure 1ÜE illustrates an embodiment of a method of operating in tens i header 320. In a step S310, user interface 2413, 102, Í04 prompts the user to enter intensifier definition values. According to one embodiment, the user interface is adapted to ask the user to indicate a desired frequency resolution Z; and the highest desired repetition frequency fDmax to be detected, and further information on a desired improvement in the Simtl-Noise Ratio. The best reactive information from the SNR would wish to be introduced in the form of an incremental value of the SNR, L. Λ the highest desired repetition frequency 10 can be entered in the form of an order number Oy ^ gh, Y. In this context, the order number Oyu-h, Y is equal to the ratio (Ύ, O,., Ovu ^ h) ^ n between the highest repetition frequency (fDmax) to be detectable and the mentioned rotation speed (Fan) - fh-um ? - = F ~ omw / bgoO

According to an embodiment of the invention, user interface 2413, 102, 104 prompts the user to enter a desired frequency resolution Z (step S310), and then it is adapted to wait for an input (step S320) in the form of data indicative of a desired frequency resolution Z or an input in the form of data instructing the intensifier 320 to establish the frequency resolution Z 20 automatically. If the data indicative of a desired frequency resolution Z is entered by the user, then the data entered will be a dispenser for parameter setter 330 (step S330). If the user enters data that indicates the desire to let the Z frequency resolution seal automatically set, the user interface will (parameter 8340) tell parameter setter 330 to set the Z frequency resolution to a default value.

Then, the user interface 2413, 102, 104 prompts (S35O) that the user enter the highest desired repetition frequency to be detected. The user interface 24B, 102, 104 is then adapted to wait for input (step 8360) indicating the highest desired repetition frequency or input in the form of data instructing the intensifier 320 to set the highest repetition frequency automatically. the data indicative of the highest desired repetition frequency is entered by the user, then the data entered will be received and dispensed for parameter setter 330 (step 8370). If the user enters data that indicates the desire to let the highest repetition frequency be set automatically, the user interface will indicate (step 8380) for parameter 330 to set the highest repetition frequency to a default value, The highest repetition frequency can be entered and / or defined in the form of ran order number O _VH ; p _{; í} Y. As explained above, the order value Oyn ^ h, ¥ is a definition of the highest repetition frequency to be detectávd in output signal Os to be generated. When, for example, interesting handling smats can occur over y times per revolution of the monitored axis 8, SOÍA. 801B, 801C, 803 the order of value Ov _{H. s0} „Y must be set to at least y. Using numbers, this means that when interesting bearing signals occur approximately 100 times per revolution of the monitored axis 8, 801 A, 801B, 801C, 803, the Y value order must be set to at least 100 .

Then, the user interface 24B, 102, 104 prompts (8,390) for the user to enter. a desired improvement of the SNR. The user interface 24B, 102, 104 is then adapted to wait for an input (step 8400) indicating an improvement in the desired SNR or an input in the form of data instructing the miensifier 320 to establish the SNR improvement automatically. the indicative data for improvement of the SNR have been entered by the user, then the entered data will be received and dispensed for the parameter setter 330 (step S410). If the user enters data that indicates the desire to let the SNR improvement be defined automatically, the user interface will indicate (Step 8420) for parameter 330 to set the SNR improvement to a default value. The improvement of the SNR can be introduced in the form of an incremental value of the SNR, L.

The control values are dispensed for the parameter setter 320 through ports 335 (Fig. 10C and 10Fç

Parameter definer 330 has a revolution maker 340 coupled to receive the control values Z and Y. The revolution generator operates 340 to calculate a value of X _E The X _E value tells how many intensified revolutions '' of the monitored axis 8, SOLA, 80 IB, 801C <803 the samples in the output signal (see Fig. 10D, and / or Fig. 12, and / or Fig. 13) must match. For example, when the frequency resolution. Z is defined. to 1600 and the order value is set to Y ™ 100. then, according to one. embodiment of the invention, the samples on the Osi output signal must correspond to Χ _Γ . ™ Z / Y - 16 * intensified revolutions of the monitored axis 8, 80LA, 801B, 801C, 803. Thus, the revolution calculator 340 has inputs to receive data indicative of a Z frequency resolution setting value and indicative data of a defined order value ¥. The revolution cooker 340 generates an X ^ data value. in response to the value of the frequency resolution setting Z and data indicative of a defined order value Y.

The revolution calculator 340 dispenses the Xr data value for an Output Signal Length Calculator 345.

As illustrated in Figure I0C, the intensifier has an input 350 for receiving data indicative of the sample rate of the signal Stíeu received at input 315. With reference to figure 9, figure 16 and figure. 30, can the sample rate value f _S r match the value or tQ?

Intensifier 320 also has a 360 input to receive data indicative of a rotation speed f τ. For some machines, the speed of rotation is pre-set to a constant value and, in such ease, this speed value can be supplied at input 360. Alternate, a speed detector 420 (Fig. I and Figure 5 and Figure 29 ) can be provided to deliver a signal indicative of the rotation speed f _ROT of axis 8. The rotation speed of the axis 8 can be provided in readings of 5 revolutions jxir second, rps, that is, Hertz (Hz).

{.) output signal compliance driver 345 operates to calculate one. Ol value indicative of the number of OroMmMtono sample values required in the Cfo output signal (See Fig. 10D), in response to the received data, that is, in response to the value of “intensified 10 revolutions” of the X axis of the speed of the rotation axis f _R0T and the value of the sample rate

Thus, if Xe ™ 16, the sample rate value f « _R - 30.72 Hz and the axis rotation speed value f _{R <rt} ^:::: 0.12 rps, then the number of sample values output signal Cfo will be Ot Xr. * IWficn 4096.

Thus, according to an embodiment, the minimum number of sample values O _L required is the output signal Cfo, Smdp. in order to allow a later analysis of the repetition frequencies up to the order OvthgiH V> with a frequency resolution Z can be calculated depending on the parameters Y, Z, fg _O rc fss. where f _{Sfe is} a rate value of 20 samples such that the number of samples per revolution of the monitored axis 8.

801 A, 80IB, 80IC, 803 is constant. The number of samples per revolution of the monitored axis is constant when the rotation speed is constant, and / or when a fractional decimator is used to compensate at a variable axis speed, as discussed in more detail later in this document.

l / subsequently, the number of sample values O _.; · The amount to be generated must be O: or higher, where O ~ * f _SR / i

The output signal length calculator 345 operates to calculate a value of O * to establish the value Ocomísumext- The value of

OniMpRjMí.NTo is set to a value equal to or greater than the calculated value Or

The calculator output signal of compliance 345 operates to dispense the value _r <pure · ímcjííms-hand input of a calculator 364 input signal strength calculator 365. 0 output signal of length 345 also operates to deliver assert compression & an attenuated adjustment operator? stochastic signal frequency 370. The stochastic signal frequency attenuator adjustment operator 370 is arranged to establish a variable S _{N k.ro. The variable SjMoo controls the frequency limit for the attenuation of stucco signals.

As can be seen in Figure 10D, the value divided by that of the sample rate fsu corresponds to a period of time Ί \

Is Select * fsx

Where Tsr can represent the length of time between two consecutive samples. Only the number of delay or displacement samples between the SI and S2 signals to be correlated, as can also be seen in Figure 1OD.

When the variable S ^ ícks set to the same value as 0 <OMPRiMLurm then, stochastic signals with a corresponding frequency isro {? H'AS'nc ... M. \> I 1 / Ts and higher frequencies will be attenuated in the signal Therefore, it is advantageous to set the Select variable to a value equal to O length ott to a value greater than OcoMERtMEKU) 'Thus, the stochastic signal frequency adjustment operator 370 is arranged to establish the variable Similar to a value equal to OoMraiMcnn.? or to a value greater than O <.ovouMrxmThe input signal length calculator 365 operates pure calculating a value of e to adjust the value lc <s ^ p? .iMsmo- The value of variable l>. it is generated depending on the information indicative of SNR improvement. desired value that can be received on port 366, the value of the Select variable

6.C that can be received on port 367 and the value The cnMHUMVNao that can be received on port 364 ..

Thus, in order to be able to generate an output signal O, S _MÜP of the immensifier 320 having sample values the immensifier must receive at least sample values I »· .. at port 315. According to an embodiment, the variable value From:

k OeoMPRtMtiNTO * 1 · - * StNkao Ocomprtmenio

Consequently, it is advantageous to adjust the variable Ι <· ομρκ? Μενϊο to a value equal to I _t or to a value greater than I, ... Thus, the input signal length calculator 365 is arranged to adjust the variable Icomprimp.nfo for a value equal to I, .. or for a value greater than II. Input signal length simulator 365 is arranged to dispense the control value h, at output 332 for signal manipulator 325 (See Fig. 10C).

The input signal length calculator 365 is arranged to dispense the Icomvrímenw control value to an input of a summation determiner 375. The summation determiner 375 also has an input to receive data indicative of the variable Snaao. In addition, the sum determiner 375 also has an input to receive data 20 indicative of the number of sample values Ocomhument to be generated in the form of an output signal (.¾ $ mdp <Consequently, the frequency attenuator adjustment operator of Stochastic signal 370 is arranged to dispense the indicative data of the pure Sf ^ icro variable the sum determiner 375, and the output signal length calculator 345 is arranged 25 to dispense the indicative data of the Ooomfrjmf ^ rí value for the determiner of adds up 375.

A sum determiner 375 is arranged to generate an urn. value of C íOMrRou.Nτο in the dependence on the values, Comprímí-xuO 'θί osusuMrmn and S ^ tcío- The C value withMPRtMrNB) is arranged for a value of substantiveness equal to the difference between the value of the hx <or the sum of the values S ^ . · _5O and Oa>MPRiMhN'Tou · Thus * the summation determiner 375 can dispense with a value Ue C <'gmp {<ísum »> ^::: F cAiPRmíXiO” $ st ou ·· O cosipiiraixm

The sum detector 375 can be arranged to dispense the Ccomprimex m value for an output of 377 by setting the parameter 330 setting medium.

Figure IOG illustrates another embodiment of the intensifier 320 * where an embodiment 375B of the sum determiner, has an input to receive data indicating the number of sample values The length to be generated * and another input to receive the value L of the SNR intensifier. The sum detenninator 375B is adapted to generate a C-value in dependence on the values of the value of the SNR device. The summation 375B is adapted to fit f * Gcovoasaxw

The sum detector 375B can be arranged to dispense the value at output .377 of parameter setting means 330.

The output signal length calculator 345 also operates to dispense the pre-set value on an output 379 of parameter setting means 330.

As mentioned above * the signal handler 325 includes a port 326 for receiving the digital time domain signal and a port 327 for receiving a control value indicating the desired length of the input signal. 1.

Signal handler 325 cooperates with a memory 380 having plurality of memory portions. According to one embodiment, the memory may include a portion of memory 382 for storing at least consecutive sample values of IcnswiMbNiu of the S R & j signal. So, the handler of. signal 325 may, in response to receiving an activation signal at an activation input 384 * operate to read the value that IcoMVRiMENru «input 327c, then operate to receive consecutive sample values from Icompremekh> tia 326 Signal handler 3.25 can also, in response to receiving an activation signal at an activation input 384. in cooperation with memory 380, operate these sample values in memory portion 382. Thus, the content of the portion of memory 382 represents input signal I, as shown in Figure 10D.

An output sample value generator operates to generate a first portion of signal 81 and a second portion of signal S2 depending on input signal L In response to receiving an activation signal at activation input .388, the value generator sample output 386 can operate to read samples l (i ₀ | to I (ie ^{μ C} length) * 4 store these, samples in a second portion of memory 390, as a portion of the signal Sl; and the sample value generator of output 386 can operate to read samples I (i <5 'Select r 1 1) to I (8,.: ..- v (..íjí.ímfíííM θοοΜΡΐυΜΕΝϊο' 1) store the samples in a third portion of memory .392 , where i ₀ is a positive integer constant.

Thus, the contents of memory portions 390 and 392. respectively, may represent the first portion of signal SI and a second portion of signal S2, as shown in Figure 10D. Then, the output sample value generator 386 was able to operate to perform cross correlation of SI and S2 signals.

Alternatively, the correlation involves reading the sample values of input signal 1 stored in memory portion 382, as shown schematically in Figure 10C and at the top of Figure IOD. With reference to Figure I 0F. the output sample value generator can operate to perform the following steps:

Step S5O0: Establish a variable t for a first ty value. The first value of t $ _} can be 11.

Step 8510: Calculate a value of the sampled output

SmoAD · y, GP G * 5 ^ -00 * · D

Step S520: Dispensing the generated output sample value 'Wp ^ for output port 394,

Step 8530: Increase the counter value U o «ie, adjust t ^{:; :::} t Φ

Step S540: Check if t value is greater than Ocomprjmen-io ⁴ Ul. ^<5 t value is greater than OcuMixnxnmn ·? * · Then, generate a- signal to indicate that the total output signal has been generated- (Step S550). If the t-value is not greater than Ο ^ ομρ & μκνγο * vl.-, then repeat step 8510, using the t-value. increased.

Figure IOH is a table to illustrate an embodiment of a part of the calculation in step S 510. The intensifier 320 is adapted to generate an output sample value SmuG) depending on a plurality C length of input signal products P (I , t), Qomprlmunxo is a positive integer.

With reference to table 1 (see Figure IOH), an input signal product P (L t) for an output sample position t is obtained by multiplying the first input sample value (b in a first sample position i per second input sample value I (i + t ·! ·· Snono; - The second input sample value is determined by a second sample position i * t ⁴ S ^ iao in the input signal vector I (See figure 10D or Figure 11), so the second input sample value is separated from the mentioned first input sample value by a certain number of sample positions H. This certain number of sample positions can be Ne ~ (i * t '>S;mck>: - i “14- 8 enk'k> Thus, the certain number N ,. can be equal to the sum of the output sample position value t and the certain value S ^ .m.

As indicated above in relation to the description of the IOD figure, the certain S ^ teio value is a number of sample positions that can correspond to a period of time T _s When the short Sjmckí value is set to the same value as Oa ^ moin, then stochastic signals with a frequency corresponding to max c and higher frequencies will be> attenuated at the signal output Smdp- The value of this limit frequency value l-STOCHASOO ^ MAX: et ls nX'UA;: z; and MAX B Fs. Where

I \ ·· SíNkvrxFsR. ondef $ R sample rate of the input signal 1.

Thus, according to a preferred embodiment, the certain number N _t . is equal to or greater than the certain value Thus, according to a preferred embodiment, the difference Nc between the two index values of the two terms in an input signal product P (i, t) is equal to or greater than the right S ^ icio value

In the example above, one term is the first input sample value 1 '(i) having index i, and the other term is the second input sample value of 1 (i -rt -r Sinejo »having index value i · * · 1 * SrOíso- In this context, it is important that the index values í, ei * tx Sjxfoto, respectively, are values associated with sample values within the input signal vector L Thus, the IcoMPRmtxro range and sample values input values and the index values i, e. í ete 8; xi <xu _: respectively, must be selected so that the index values are values within the input signal vector, with reference to the top of Figure 10D _: , which illustrates an embodiment of the input signal vector I, this means that the index values í, eitt · * · S ^ no., respectively, must be values in the range z5 of i; XR. '. so for Úxícíu ^ length ~ 1 - So, if the start constant is set to i ^ eio h then the index values i, ei t · * Sínício., respectively, must be values in the range of i ™ la i 1 <· ο.μγκιμεντ <·> ·

The input signal 1 can include sample values 1 length> as mentioned above. The intensifier receives an input signal vector having a first plurality of input sample values. This first plurality of input sample values is processed in order to generate a Smdp output signal sequence having a second plurality. of sample output values S Mn-KfK ^the said second plurality being a positive integer.

An output sample value SmdBQ is calculated depending on a third plurality of input signal products F (i, t); the mentioned third plurality (C length) being a positive integer.

As indicated above in equations (l) and (3), the following relationship can be used according to an embodiment;

í 1,) iCOMPRiMF ΝΊΌ OcCOMPRESSION ΓΟ * E * SlNÍCiO + OcOMPRiΜΕΝITO c

(a) Cr <fMPIí.íMENU> ~~ leOMrRl.Mé.NiO- SínÍVIO - Ο <· <^. ξ? ί <; Μί'.ΝΓΟ

As an example, the following numerical values can be used;

L - 10

OILENGTH “* 024

S _? : mooM024

C length ~ 10-240 ^ LENGTH “13,288

So, for example, S ^ icio 1024, et vary from t “t min“ to tt _MA>; ™ () length ^:::: 1024, and the following equation (8) IS used:

OU 0 ·. (t :) -] ζ / (0 * / (Μ · $ ra>> W) then a. Nc difference between the dot index values of the two terms will vary from Nc ™ 1025 to Ne ^{; ::;} 2048, This is because difference of greatest difference in index value will be N <m _As - · S ₅ ní <tu 'tmax ····' S

The _s <ΐ \ ϊ · ί <5 \ ΐί uro 1024 -ν 1024 ·· 2048!; and the smallest difference in index value will be Ncv.m S ^ _fJO 4 - 1024 - I 1025.

Thus, if the constant '' 1, the input signal vector 1 must then have index values ranging from i - i;> · ~ · 1 to W.muMimm ^:::: 12288.

With reference to Figure K) C, the sample values of Smíj?

(t) dispensed over output port 394 must be dispensed to memory 396, and memory 396 can store the sample values received so that they are read as a sequence of sample output values Oso Swot ·, as schematically illustrated in the lower left corner 10 in figure 10D.

Alternatively, output sample values (t) dispensed over output port 394 of output sample value generator 386, can be delivered directly to output port 398 of intensifier 320.

According to another embodiment, the equation for generating a sample value (output (Sm ^ U)) can be modified to read:

í) S.xjj t) ™ / 0 ') * / (f 4- /)

The above equation (9) will provide an output signal sequence O, S.mdp which is equivalent to the output signal sequence Ο, generated by equations (5) and (8) above. It can be seen that equation (9) is an alternative way of expressing equation (5).

In this way, also according to equation (9), embodiment to generate an individual value of the output signal sample (t), the number of sample positions Nc among the sample values to be multiplied will be N <'··· 14 Scqao.

Decimation: .tk.Db9..d9..ãui <islra

As explained above in connection with Figure 9. it may be desirable to provide a decimator 310 to reduce the sampling frequency of the digital signal before dispensing for intensifier 320. Such a decoder

310 advantageously reduces the number of samples in the signal to be analyzed, thereby reducing the amount of memory space required to store the signal to be used. Decimation also allows for a

........ ............ ........ ................ ...... ..::> ............................................. ............................ X ........ ............. ........... faster processing in the subsequent 320 immenser.

Figure 14A illustrates a series of sample values of the signal dispensed for the input of decimator 310, and figure 14B illustrates the sample output values, of the corresponding time period. The signal being input to the decoder 3 '10 can have a sampling frequency f _s . As can be seen, the output signal is has a reduced sampling frequency f <^. The decimator

310 is adapted to perform a digitally encircled signal decimation

Senv in order to dispense with a digital signal with a reduced sample rate fzu such that the output sample rate is reduced by a whole factor M, compared to the input sample rate f $.

Thus, the output signal Sreo includes only each M-th sample value present in the input signal S _EN v. Figure 14B illustrates an example where M is 4, but M could be any positive integer. According to a method of carrying out the invention, the decimator can operate as described in US 5,633.81l. whose content is incorporated by reference here ..

The figure. I5 A illustrates a decimator 310 according to an embodiment of the invention. In embodiment 3.10A of decimator 310 according to Figure 15A, a comb filter 400 filters and tenth the input signal at a ratio of 16: 1, That is, the output sample rate is reduced by a first integer factor Ml of sixteen (ΜΊ 16). compared to. input sample rate .. A finite impulse response (FIR) 401 receives the 2nd> output of the exempt filiro 400 and provides another reduction of the sample rate by a second integer factor M2. If the entire factor M2 - 4, the FIR 401 filter provides a 4: 1 reduction in the sample rate and therefore the 3.10A decimator will provide a total decimation of 64: l.

Figure 15B illustrates another embodiment of the invention, where / Jt embodiment 31 OB of decimator 310 includes a low-pass filter 402, followed by a sample selector 403. Sample selector 403 is adapted to collect each m- th sample of the signal received from the low pass filter 402. The resulting signal knt is a sample rate of f ^ u ^:::: fi / M, where f _s is the sample rate of the received signal S ^ v. The cutoff frequency of the 402 low-pass filter is controlled by the value of, M.

According to an embodiment, the value M is predefined for a given value. According to another embodiment, the M value can be adjustable. Decimator 310 can be adjusted 10 to make a selected Mrl decimation. where M is a positive integer, the value of M can be received on a 404 port of decimator 310.

The cutoff frequency of the low pass filter 402 is f $, <? / (G * M) Hertz. », The G factor can be selected for a value of two (2.0) or a value greater than two (2.0). According to an embodiment, the value G 15 is selected for a value between 2.5 and 3. This also makes it possible to avoid aliasing. The low-pass filter 402 could be represented by a déFIR filter.

The signal emitted by the low-pass filter 402. is dispensed for sample selector. 40.3. The sample selector receives the value of M on one port and the low-pass filter signal 402 on another port, and generates a sequence of sample values in response to these inputs. The sample selector is adapted to collect each M-th sample of the signal received from the 402 low pass filter. The resulting signal has a sample rate of fsR { ^:::: i / M * fi „where f _s is the rate sample of a signal received on port 405 25 of decimator 310.

A method for compensating for variable shaft speed

As mentioned above, a repetitive signal signature present in the input signal can advantageously be detected using the method described above, even when the repetitive signal signature is so weak as to generate a component of amplitude smaller than that of the signal components stochastic.

However, in certain applications, the rotation speed of the shaft may vary. Perform the method described with reference to $ figures 1 0-1 3 using an input measurement sequence where the rotation speed of the etxo varies. leads to deteriorated signal quality from the resulting Smdp output signal ·

Consequently, an objective of an aspect of. The invention is to achieve the same high quality of the resulting block Y when the axis rotation speed 10 varies, as when the axis rotation speed is constant during the complete measurement sequence.

Figure 16 illustrates an embodiment of the invention including a decimator 310 and a. intensifier 320. as described above, and a fractional decimator 470.

According to one embodiment, while the decimator

310 operates to declare the sample rate per M: L where M is an integer, the embodiment of Figure 16 includes a fractional decimator 470 to decimate the sample rate by ü / N, where both U and N are numbers positive integers. Thus, the fractional decimator 470 advantageously 20 allows the decimation of the sample rate by a fractional number. According to one embodiment, the values of ü and N can be selected to be in the range 2-2000. According to one. embodiment, the values of U and N can be selected to be in the range of 500-1500. According to yet another embodiment, the values of U and N 25 can be selected to be in the range of 900-1100.

In the figure 16 embodiment, the output signal from decimator 310 is dispensed to a selector 460. The switch allows one. selection of signal to be entered in the intemúfieador 320. When monitoring the condition is done on a rotating part and with a constant rotation speed, the select? 460 can be adjusted in position to dispense the signal having sample frequency f _s ? J for input 315 of the intensified? 320, and fractional decimator 470 can be deactivated. When condition monitoring is performed on a rotating part with a variable speed of rotation, the fractional decimator * 4'70 can be activated and the selector 460 can be placed in the position to dispense the Srhj> ₂ signal having a sample frequency for the input 315 of the 320 intensifier.

The fractional decimator 4'70 has an input 450. Input 480 can be coupled to receive the output signal from decimator 3.10. The fractional decimator 470 also has an input 490 to receive information indicative of the rotation speed of axis 8.

A speed detector 420 (see Figure 5 and Fig. 1 and Fig. 29) can be provided to dispense a signal indicative of the rotation speed of axis 8. The speed signal can be received at. a port 430 of processing means 180, thereby allowing processing means 180 to dispense this speed signal to input 490 of fractional decimator 470. The rotation speed f ^ _0T of axis 8 can be provided in terms of revolutions per second, ie. Hertz (Hz).

Figure 1.7 illustrates an embodiment of fractional decimator 470 that allows changing the sample rate by a fractional number U / N, where U and N are positive integers. This allows a very precise control of the sample rate to be dispensed to the intensifier 320, thus allowing very good detection. of weak repetitive signal signatures, even when the axis speed varies.

The speed signal received at the entrance. 490 of fractional decimator 470, and dispensed for a fractional number generator 500. The fractional number generator 500 generates integer outputs U and N at outputs 510 and 520, respectively. The U output is dispensed with an upsampler 530. The upsampler 530 receives the Sreo signal (see figure 16) through the input

480. The upsampter 330 is a sample intruder 540 for entering sample values Ul between each sample value received at port 480. (/ The added sample value is provided with a large amplitude value. According to a realization, each sample value added is a zero amplitude (O).

The resulting signal is dispensed to a low-pass filter 550 whose cutoff frequency is controlled by the value of U dispensed by the fractional number generator 500. The filter cutoff frequency passes. ~ Bai.xa 550 is I'sr.rRR · * U) Hertz. The K Factor can be selected for a value of two (.2) 10 or a value greater than two (2).

The resulting signal is dispensed to a Decimator 560. Decimator 560 includes a low-pass filter 570 whose cut-off frequency is controlled by the value of N dispensed by the fractional number generator 500. The cut-off frequency of low-pass filter 570 is tQ <_:; Z (K * N) Hertz. The 15 K factor can be selected for a dots value (2) or a value greater than two (2).

The signal emitted by the low-pass filter 570 is dispensed for the sample se.let.or 580. The sample selector receives the value of N on one port and the low-pass filter signal 570 on another port, and this generates a sequence of sample values in response to those entries. The sample selector is adapted to collect each N ~ is a sample of the signal received from the low-pass filter 570. () resulting signal Sr ^ has a sample rate of tJ / N * where Hri is the sample rate of a Sreu signal received at port 480. The resulting signal is dispensed at an output port 590,

Low-pass filters 550 and 570 can be realized using FJR filters. This advantageously eliminates the need to perform multiplications with the zero-amplitude values introduced by the sample iot.rodi.ttor 540.

Figure 18 illustrates another embodiment of the fractional decimator 470, () the embodiment of figure 18 significantly reduces the amount of calculation required to produce the $ _REO2 signal.

In the embodiment of figure 18. the low-pass filter 570 has been eliminated, so that the signal dispensed by the low-pass filter 550 is dispensed directly to the sample selector 580. When the fractional stripper 470 is realized by hardware, the embodiment of figure 18 vant.ajosamen.te reduces the amount of hardware, thus reducing the cost of production ..

When fractional stripper 470 is realized by software, the embodiment of figure 18 advantageously reduces the amount of program code that needs to be executed, thus reducing the load on the processor and increasing the execution speed.

Referring to Figures 17 and 18, the resulting signal that is dispensed by the fractional deductor 470 output port, has a sample rate of 1'sr2 ™ tJ / N * f sri where Cm is the sample rate of a Srw signal received at port 480. The fractional U / N value is dependent on a rate control signal received at an input port 490. As mentioned above, the rate control signal can be a sign indicating the rotation speed of axis 8 , which can be dispensed with by the speed detector 42.0 (see Figure 1 and / or Figure 5). The speed detector 420 can be realized by an encoder, providing a pulse signal with a resolution duly selected in order to provide the desired accuracy of the speed signal. In one embodiment, encoder 420 dispenses a complete revolution marker signal once around the entire axis 8. Such a revolution marker signal can be in the form of an electrical pulse having an edge that can be accurately detected and indicative of a certain rotation position of the monitored axis 8 .. According to another embodiment, the encoder 420 can dispense many pulse signals per revolution of the monitored axis, in order to allow the detection of speed variations also within a revolution of the axis.

According to one embodiment, the fractional number generator SOO controls the values of IJ and N, so that that of the reduced sample rate F 'm has a value to provide a signal S ^ or-where the 5 number of samples per revolution of axis 8 is substantially constant, regardless of any variation in velocity of axis 8. Consequently: the higher the U and N values, the better the ability of fractional deducer 470 to maintain the number of sample values per revolution of the axis 8 at a substantially constant value.

Fractional decimation, as described with reference to the

Figures 17 and .18, can be obtained by carrying out the corresponding steps of the method, and this can be achieved by means of a computer program 94 stored in memory 60, as described above. The computer program can be run by a DSP 50.

Alternatively, the computer program can be run via a Field Programmable Gate Array (FPGA) circuit.

The method described in connection with Figures 10-13 and the decimation described with reference to Figures 17 and 18 can be performed by the analysis apparatus 14 when processor 50 executes the corresponding program code 94, as explained in conjunction with Figure 4 above. The processor. Data 50 may include a central processing unit 50 for controlling the operation of the analysis apparatus 14, as well as a Digital Signal Processor (DSP) 50B. The DSP 50B can be arranged to run the program code 90 causing the analysis device 14 to execute the program 94 causing the process described above in connection with figures 10-13 to be performed. According to another embodiment, the 50B processor is a Field Programmable circuit (Jate Array (FPGA

Figure 19 illustrates decimator 310 and another embodiment of fractional decimator 470, Decimator 310 receives the signal Sj.-v by reading a sampling frequency f _s <^ n a port 405, and an integer M em. a 404 port, as described above. Decimator 310 dispenses a single signal having a sampling frequency G1 over output 312, which is coupled to input 480 of fractional decimator 470A. The output sampling frequency f sm e

Gr-GM where M © an integer.

Does the fractional decimator 470A receive the signal S ^> _? , having a 10 sampling frequency This as one. sequence of data values S (JK c does not require an output signal like another sequence of data values R (q) in its output 590.

The fractional decimator 470A may include a memory 604 adapted to receive and store the data values as well as information indicating the corresponding speed of rotation f _KOr of the monitored rotating part. Thus, memory 604 can store each value of. Sy data, so that it is associated with a value indicating the rotation speed of the monitored axis at the moment of detecting the signal value of the sensor S _EA corresponding to the data value S q>.

When generating output data values R (q), fractional decimator 470A is adapted to read the values of, data 8 as well. Information indicative of the corresponding rotation speed f ^ _or memory 604.

The data values $ m. read from memory 604 are dispensed to sample introducer 540 for entering sample values IJ ·· I between each sample value received at port 480. Each sample value added is provided with an amplitude value. According to an embodiment, each sample value is added and a zero amplitude (0).

The resulting signal is dispensed with a 550 low-pass filter whose cutoff frequency is controlled by the value of U dispensed by the fractional number generator 500, as described above.

The resulting signal is delivered to sample scanner 580. The sample scanner receives the value of N on one port and the low pass filter signal 550 on another port, and generates a sequence of sample values in response to those inputs. The sample selector is adapted to choose each N-est sample of the signal received from the 550 low-pass filter. The resulting signal S _R r ( _); has a sample rate of f _Sí i-> ~ U / Ν '* f _SRb where f _{SR} is} the sample rate of a signal S _RE {> received at port 480. The resulting signal is dispensed by output port 590 .

Thus, the sampling frequency f, R2 of output data values R (q) is less than the sampling frequency of input fsrn by a factor D. D can be defined as an arbitrary number greater than 1, and can be a fractional number. According to the preferred embodiment, factor D is adjustable for values between 1.0 and 20.0. In a preferred embodiment, factor D is a fractional number adjustable to between about 1, 3 and about 3.0. (.) factor D can be obtained by adjusting integers U and N to appropriate values. The factor D is equal to N d. Debt owed by th

D N / li

According to one. embodiment of the invention, the integers U and N are adjustable for large integers, in order to allow the factor D ^:::: N / U to accompany speed variations with a minimum of inaccuracy. Selection of variables ü and N as integers greater than 1000 advantageously provides high precision in adapting the output sample frequency for tracking changes in the rotation speed of the monitored axis. Thus, for example, adjusting N to 500 and U to 1001 provides D 2.002.,

The variable D is set to an appropriate value at the beginning of a measurement and that value is associated with a given rotation speed of a rotating part to be monitored. Posted ormeme, during the condition monitoring session, the D fractional value is automatically adjusted in response to the rotation speed of the rotating part to be monitored so that the signal emitted at port 590 provides a sub-substantially constant number of sample values per revolution rotated part monitored.

As mentioned above, encoder 420 can dispense with a complete revolution marker signal once around the end of etxo 8. I. The complete revolution marker signal can be in the form of an electric pulse having an edge, which can be accurately detected and indicative of a certain rotation position of the monitored axis 8. The complete revolution marker signal, which can be referred to as an index pulse, can be produced at a 420 encoder output in response to the detection of a pattern zero angle on a coding disc that rotates when the monitored axis rotates. This can be achieved in a number of ways, as is well known to the person skilled in the art. The encoding disc can, for example, be provided with a zero angle pattern that will produce a zero angle signal with each revolution of the disc. Speed variations may be found, for example, by recording one complete revolution marker '· in the memory 61) 4 each time the shaft monitored passing through deiermínada tie rotation position "and the association ^fi complete revolution mareador" with a sample value Síj) received at the same moment. In this way, memory 604 will store a larger number of samples between two consecutive full turn markers when the axis rotates slower, since the A / D converter dispenses a constant number of samples f $ per second.

Figure 20 is a block diagram of decimator 310 and yet another embodiment of fractional decimator 470. This embodiment of fractional decimator is denoted 47òb. This freeware decimator 470b may include a memory 604 adapted to receive and store the data vaults as well, information indicative of the corresponding rotation speed f _ROÍ of the monitored rotating part. Thus, memory 604 can store each value of data S _? .n to be associated with an indicative speed value. of rotation of the monitored axis when the signal value of the Sea sensor corresponding to the data value S .. is detected.

The fractional decimator 470b receives the signal S _{RW> {} , having a sampling frequency ^ _RB as a sequence of data values S and dispenses with an output signal Srelu. having a sampling frequency f ^ as another sequence of data values R (q) at output 590.

The fractional decimator 470b may include a memory 604 adapted to receive and store data values S as well as information indicative of the corresponding speed of rotation f of the monitored part in rotation. 604 of memory can store data of values S (J), in blocks so that each block is associated with a value indicating a relevant speed of the monitored axis rotation, as described below in relation to Figure '21.

The fractional decimator 470b can also include a fractional variable decimation generator 606. which is adapted to generate a fractional D value. The fractional value D can be an active number 11. Thus, the fractional number can be controlled to a floating number value, in response to a received speed value f _R0T so that the floating number value is indicative of the speed value f _R of with some inaccuracy. When implemented by a properly programmed DSP, as mentioned above, a. inaccuracy of the floating number value may depend on the DSP's ability to generate floating number values.

In addition, the fractional decimator 470b may also include a FIR 608 filter. The F.IR 608 filter is an F1R low-pass filter having a certain low-pass cut-off frequency adapted for decimation by a D _WAX factor. The D _MAX factor can be adjusted to a suitable value, for example, 20,000. In addition, fractional decimator 470b can also include a 610 filter parameter generator.

Fractional decliner operation 470b is described with reference to figures 21 and 22 below.

Figure 21 is a flow chart illustrating an embodiment of a method of operation of the decliner 31.0 and fractional decliner 470b of Figure 20.

In a first step $ 2000, the rotation speed F _R o. · Of the part to be monitored condition is recorded in memory 604 (Fig, 20 and 21), and this can be done substantially at the same time as the measurement of vibrations or impulses shock start. According to another embodiment, the rotation speed of the part to be monitored is observed for a period of time. The highest detected speed of Fornax and the lowest detected speed F can be recorded, for example, in memory 604 (Fig. 20 and 21).

In step S2010, the recorded speed values are analyzed in order to establish whether the speed of rotation varies. If the speed is determined to be constant, the selector 460 (Figure 16) can be automatically adjusted in position to dispense the signal S ^., _S > having a sampling frequency for input 315 of intensifier 320. and fractional decoder 470, 470b can be disabled. If the speed is determined to be variable, the fractional decimator 470, 470b can be activated automatically and the selector 460 is automatically adjusted in position to dispense with the Sjmrn signal, having sampling frequency Çr? to input 315 of intensifier 320.

In step S2020, user interface 102, 106 displays the recorded speed value or b <! O'few.> ÍWrm & x speed values. u prompts a user to enter a desired order value ()., As mentioned above, the rotation frequency of the f- _ROT axis is often referred to as “order Γ. Interesting signs can occur around. ten times per axis revolution (Order 10). In addition, it may be interesting to analyze sohretons for some signals, so it may be interesting to measure up to the order of 100, or order 500, or even more. Thus, a user can enter a 5 order number O _v using user interface 102,

In step S2030, an appropriate outflow rate f _S R3 is determined. According to one embodiment, output sample rate Am is set to f _SR2 C * Ov * f rot mà »where

C is a constant with a value greater than 2.0

·, Is a number indicative of the relationship between the rotation speed of the monitored part and the frequency of repetition of the signal to be analyzed, fROFmiB is the lowest rotation speed of the monitored part expected during a close measurement session. According to one embodiment, the value hnrtnin is a lower speed of rotation detected in the step $ 2020. as described above,

Λ constant C can be selected for a value of 2.00 or greater, taking into account the sampling theorem. According to embodiments of the invention, the constant C can be predefined to a value between 2.40 and 2.70,

2ü where k is a factor having a value greater than 2.0

Consequently, the k factor can be selected for a value greater than 2.0. According to one embodiment, the C factor is advantageously selected, so that 100 * C / 2 provides an integer. According to an embodiment, the factor C can be adjusted to 2.56.

Selecting C pam 2.56 provides I00 * C ™ 2.56 ==== 2 raised to 8.

In step S204Ô, the integer value M is selected according to the detected speed of the rotation f _RCs r of the part to be monitored. The value of M can be selected automatically depending on the detected rotation speed of the part to be monitored so that the reduced intermediate sampling frequency is greater than the sampling frequency of the desired output signal. The value of the sampling frequency f ^ ₅ also reduced and selected depending on how much of a rotation speed variation is expected during the measurement session. According to one embodiment, the sample rate D of the A / D converter can be 102.4 kHz. According to an embodiment, the integer value M can be adjusted to a value between 100 and SI2 in order to provide values of reduced intermediate sampling frequency between 1024 Hz and 100 Hz.

In step $ 2050, a variable fractional elimination value D is determined. When the rotation speed of the part to be monitored condition varies, the variable fractional decimation value D will vary according to the momentary value of the detected speed.

According to another embodiment of steps S2040 and S2050, the integer value M is defined in such a way that the reduced intermediate sampling frequency f _{S {U} is, through the menus, a percentage so much greater that (as determined in a step. $ 2030 above ) regarding the relationship between the highest detected speed value ikoona?, divided by the lowest detected speed value According to this embodiment, a maximum variable fractional decimation value D ^ ax is adjusted to a value of D _maX and a value minimum fractional decimation variable Ι.χ _βΝ is set to 1.0. Then, an instantaneous real-time measurement of the actual speed value f _R0T is made and a fractional momentary value D is accordingly adjusted.

f _RO T «the indicative value of a measured speed of rotation of the rotating part to be monitored

In step S2060, the actual measurement is started, and a desired total measurement duration can be determined. This duration can be determined depending on the degree of attenuation of the stochastic signals required in the immensitizer. Thus, the total desired duration of the measurement can be defined so that it corresponds to or exceeds the duration necessary to obtain the input signal I as discussed above in connection with figures 10A to 13.

As mentioned above, in connection with figures 10A to 13, yet another ic input signal provides the effect of better attenuation of the stochastic signals 5 in relation to the repetitive signal patterns in the output signal.

The total duration of the measurement can also be determined depending on the desired number of rotations of the monitored part. When the measurement is started, the decimator 310 receives the digital signal S _ENV at a rate fs and dispenses a digital signal S at a reduced rate f $ r · ~ f $ / M for the input of fractional decimator 480. Next, the signal Sked · is explained in terms of a voltage signal sample values S _; .r „where j is an integer.

In step S207Ü, data values are written to memory 604, and a rotation speed value ί '^, η is associated with each data value. According to an embodiment of the invention, the value of rotation speed 15 is read and recorded at a rate t'k <™ 1000 times per second. The read and write rate f _RR can be set to other values, depending on how much the speed of the monitored rotating part varies.

In a subsequent step S2081), it analyzes the recording speed of rotation values, and divides the recorded data values into 20 data blocks depending on the rotation speed values. In this way, a number of blocks of data block values Sp> can be generated, each block of data values Sp _; being associated with a rotation speed value. The rotation speed value indicates the rotation speed of the monitored part, when these particular data block values were recorded. Individual data blocks can be of mutually different sizes, that is, Individual blocks can contain mutually different numbers of data values S

If. for example, the monitored rotating part first rotated at a first speed f _R <_{> T} ^ for a first period of time, and then changed speed to rotate at a second speed Iroq. for a second shorter period of time, the recorded data values S »p _? can be divided into two data blocks, the first block of data values being associated with the first speed value 5 Írotu and the second block of data values being associated with the second speed value ίχοπ «In this case, the second data block would eat fewer data values than the first data block, since the second period was shorter.

According to an embodiment, when all 0 recorded data values S _{<?} Have} been divided into blocks, and all blocks have been associated with a rotation speed value, then the method proceeds to execute step S2090.

In step S2090 * select a first block of data values S φ, and determine a fractional elimination value D corresponding to the 5 associated speed of rotation value f _R o _T , this fractional decimation value D is associated with the first block of values of Sos data According to a realization * when all the blocks have been associated with a corresponding fractional deduction value D, then the method proceeds to execute step S2090. Thus, the fractional dedding value 0 is adapted depending on the velocity Írot

In step S2I (X), select a block of data values S _in and the associated fractional decimation value D * as described in step S2090 above.

In step $ 2110, it generates a block of output values R in response to the selected block of input values S and the associated fractional decimation value D 5. This can be done as described with reference to Figure 22.

In step S2I20 * it checks if there are any remaining input data values to be processed. If there is another block of input data values to be processed, then repeat step S21O0. If there is no remaining block of input data values to be processed * then the measurement session will be completed.

Figures 22A, 22B and 22C illustrate a flow chart of an embodiment of a method of operating the fractional decimator 470b of Figure 20.

In a $ 2200 step, it receives a block of input data values S _{ j _} and a specific fractional decimal value D associated with it. According to an embodiment, the received data is as described in step 82100 for Figure 2f, The input data values S _ÍJ} in the received block of input values, data 8 are associated with the fractional decimation value specific D.

In steps 82210 to 82390, the F1R 608 filter is adapted to the specific fractional decimation value D received in step 82200, and a set of corresponding output signal values R (q) are generated. This is more specifically described below.

In a $ 2210 step, suitable filter settings for the specific fractional deci- sion value D are selected, as mentioned in connection with the Figure. 20 above, the ITR 608 filter is a low-pass filter FIR having a certain low-pass cut-off frequency adapted for decimation by a factor D max. The factor D _m .ax can be defined as a suitable value, for example, 20. A value of filter index F _R is defined as a value dependent on the factor D _MAR and the specific fractional decimation value D as received in step 8.2200, Step 82210 can be performed by the filter parameter generator 610 (Fig, 20),

In a step $ 2220, select a starting position value x at the input of data received block s (j). It should be noted that the starting position value x does not need to be an integer. The FIR 608 filter has a FiroMouramro length and the Initial position x value will then be selected depending on the filter length FcoMPkíMEmxj ° filter index value The index value filter F _{r is} as defined in step 82210 above. According to an embodiment, the initial position value x can be defined for x: “f eosiPiUMENuy f '

R.

In a $ 2230 step a sum sum of filter is prepared and set to an initial value, such as, for example, SUM: - 0.0

In a step $ 2240, a position j in the input data received adjacent and prior to position x is selected. Position j can be selected as the entire portion of x.

In a step S2250, select the position Fpos in the HR filter. that corresponds to the selected position j in the received input data. The Epos position can be a fractional number. The position of the Epos filter, in relation to the average position of the fih.ro, can be determined to be

Fpos ~ [(xj) * F ιη where Fr is the filter index value.

In $ 2260 step, check if the determined Fpos filter position value is outside the permitted limit values, that is, points in a position outside the filter. If this happens, then continue with step $ 2300 below. Otherwise, continue with step $ 2,270,

In a step S2270, a filter value is calculated by means of interpolation. Note that the values of the adjacent filter coefficients in an FIR hash filter usually have similar numerical values. So, one. Interpolation value will be advantageously accurate. First an IFpos position integer value is calculated:

IFpos: ~ entire portion of Fpos (j FVal filter value for the Fpos position will be:

FVal ™ A (IFpos) -r | A (IFpos li - A (IFpOsil * [Fpos lipos] orate A (IFpos) and A (IFpos ··: ·· 1) are values in a reference filter., And the position Fpos filter is a position between these values.

In a $ 2280 step, it calculates an update of the SEM filter sum value in response to the position signal j:

SUM: - SUM t FV & l * S (J)

In a step S2290, it moves to another signal position:

Setp j -1

Then move on to step S2250.

In a step 2300, a position j in the input data received adjacent and subsequent to the position x is selected. This position can now be selected as the entire portion of x. plus 1 (one), that is, j: I -t integer portion of x

In step 82310 select a position in the FIR filter that corresponds to the selected position j in the input data received. The position Fpos can be a fractional number. The Fpos filter position, in relation to the average filter position, can be determined to be

Fpos ™ | (J-X} * F í <J where Fr is the Filter index value.

In step $ 2320, check if the determined Fpos filter position value is outside the permitted limit values, that is, points in a position outside the filter. If this happens, then proceed with step 82360 below. Otherwise, continue with step S233O,

In an 82330 step, a filter value is calculated using interpolation. Note that the values of the adjacent filter coefficients in a low-pass FIR filter generally have similar numerical values. Thus, an interpellation value will be advantageously accurate. First an IFpos position integer value is calculated:

IFpos: whole portion of Fpos

The filter value for, the Fpos position will be:

FVal (Fpos) ^:::: A (IFpos) [A (IFpos I) A (IFpos)] * [Fpos

where A. (IFpos) and A (IFpos t I) are values in a reference filter, and the Fpos filter position is a position between those values.

In step 82340, calculate a SUM filter short value update in response to the position signal j:

SUM: '' SUM * FVal * 8 (j)

In one step 82350. move to another signal position: Setj:

Then proceed to step 82310.

In a $ 2360 step, you do not need an output data value

Ru>. The output data value R (j) can be dispensed into a memory so that the consecutive output data values are stored in 10 consecutive memory locations. The numerical value of the output data value Rru is.

R (j): - SUM In a step S2370, updates the position value x: x: - x r D

In a step 82380, it updates the position value j:

In a step 82390, it checks whether the desired number of data values is. output were generated. If the desired number of output data values has not been generated, then proceed to step S2230. If the desired number of output data values have been generated, then proceed to step $ 2,120 in the method described in relation to Figure 2.1.

Indeed, the stage. S2390 is intended to ensure that a block of output signal values R (q), corresponding to the block of input data values $ received in step $ 2200, is generated, and that when at values of 25 output signal R corresponding to input data values S have been generated, so step $ 2120 in Fig.2l should be performed.

The method described with reference to Figure 22 can be implemented as a computer program subroutine, and steps $ 2100 and $ 2110 can be implemented as a main program.

According to a further embodiment of the invention, variable axis speed compensation can be achieved by controlling the clock frequency emitted by the watch 190. As mentioned above, a speed holder 420 (see Figure 5} could be provided to dispense a signal indicative of the rotation speed f _{R? r} . · of the axis 8. The speed signal can be received on a port 430 of processing medium 180, thus allowing processing medium 180 to control clock 190 Consequently, processing means 180 may have a port 440 for dispensing a clock control signal, thus processing means 180 may be adapted to control clock frequency in response to the detected speed of rotation

As mentioned in connection with Fig. 28, the sample rate of the A / D converter is dependent on a clock frequency. In this way, the apparatus 14 can be adapted to control the clock frequency in response to the detected rotation speed f _RO T so that the number of sample values per revolution of the monitored rotating part is kept at a substantially constant value, even when the speed of rotation vary.

In accordance with yet another embodiment of the invention, the functionality of intensifleadur 320, 94 could be obtained by a method for producing autocurring data as described in US 7,010,445, the content of which is incorporated herein by reference. In particular, the digital signal processor 50 may include functionality 94 for performing successive Fourier Transform operations on the digitized signals to provide auto-correlation data.

Condition monitoring of gear systems

Note that dumb embodiments of the invention can also be used to research, monitor and detect the condition of. gear systems. Some embodiments of the invention provide, particularly advantageous effects when monitoring gear systems

Epicyclic IQ including transmissions, gears and / or epicyclic gearboxes. This will be described in more detail below. Gearboxes and / or cpi cyclic gearboxes, can also be referred to as transmissions, enerenanens emu planetary gearboxes.

Figure 23 is a front view illustrating an epicyclic gear system 700. The epicyclic gear system comprises at least one or more external gears 702, 703, 704 rotating around a central gear 701 .. The external gears' 702, 703, 704 10 are commonly referred to as planetary gears, and the central gear 701 is commonly referred to as a solar gear. The epicicy gear system 700 may also incorporate the use of an outer gear ring 705, commonly known as a circular crown. Planetary gears 702, 703, 704 can include a P number of 15 teeth707, solar gear 701 can include an S number of teeth 708, and a circular crown 705 and can include an .A number of teeth 706. The number A of teeth circular crown 705 are arranged to mesh with the number P of teeth on planetary gears' 702, 703, 704 which, in turn, are also arranged to mesh with the number S of teeth on solar gear 20 '70 L However , it should be noted that solar gear 701 is normally larger than planetary gears 702, 703, 704, which is why the illustration shown in Figure 2.3 should not be construed as a limitation in this regard. When there are different sizes in solar gear 701 and planetary gears 702, 703, 704, the analysis device 25 of 14 can also distinguish between the detected conditions of different axes and gears of the cyclic gear system 7 (10, as will be clear from follow.

In many epiccic gear systems. one of these three basic components, namely the solar gear 701. the planetary gears 702, 703, 704 ctu the circular crown 705, are kept stationary. One of the two remaining components can then serve as a 'ma. output and supply power to the 700 epicyclic gear system. The last remaining component can then serve as an output and receive power from the 700 epicyclic gear system. The input / output rotation ratio depends on the number of teeth in each gear. , and by which the component is kept stationary.

Figure 24 is a schematic side view of the epicyclic gear system 700 of figure 23, as seen in the direction of the SW arrow in Figure 23. An exemplary arrangement 800, including the epicyclic gear system 700. can include at least one sensor 10 and at least at least one analysis apparatus 14 according to the invention, as described above. The 800 arrangement can, for example, be used as a gearbox for wind turbines.

In an embodiment of arrangement 800, circular ring 705 is held in place. A rotating shaft 801 has several movable arms or carriers 801 A, 801B, 80IC arranged to fit with planetary gears 702, 703, 704 ·. By providing an input rotation 802 to the rotary axis 801, the rotary axis 801 and the movable arms 801. A, 801B, 801C and planetary gears 702, 703, 704 can serve as an input and provide energy for the gear system epicyclic 700.0 rotary axis 80.1 and planetary gears 702, 703, 704 can then rotate in relation to solar gear 701. Solar gear 701, which can be mounted on a rotary axis 803, can thus serve as an outlet and receive power from the epicyclic gear system 700. This configuration will produce an increase in the gear ratio G ··· lt (A / S) -.

As an example, the gear ratio G when used in a gearbox on a wind turbine can be arranged in such a way that the outward rotation is about 5-6 times the inbound rotation. The planetary gears 702, 703, 704 can be mounted, using handwheels 7A. 7B and 7C, respectively, on movable arms or carriers 801 .A, 80 IB and 80IC (shown in both Figures 23-24). The rotating shaft 801 can be mounted on 7D bearings. Likewise, the rotating shaft 803 can be mounted on bearings 7E, and solar gear 701 could be mounted, via bearings 7F, on the rotating shaft 803.

According to an embodiment of the invention, the at least one sensor 10 can be connected to. or, on a measuring point 12 of the fixed circular crown 705 of the epideck gear system 700. The sensor 10 can also be arranged to communicate with the analyzer 14, The analyzer 14 could be arranged to analyze a. condition of the epiddiea '700 gear system based on measurement data or signal values emitted by sensor 10, as described above in this document. The analysis apparatus 14 may include an evaluator 230 as above.

Figure 25 illustrates an analog version of an exemplary signal produced and emitted by the pre-processor 200 (see Figure 5 or Figure 16) in response to signals detected by at least one sensor J0 when the epieyclic gear system 700 is rotated in array 800. The signal is shown for a period of T ^ .y. which represents signal values detected during a revolution of the SOL rotary axis It is necessary to understand that the signal dispensed by preprocessor 20 (1 through port 260 (see Figure 5 and Figure 16) can be dispensed by input 220 of evaluator 230 ( see Figure 8 or Figure 7).

As can be seen from the signal in Figure 25, the amplitude or signal output increases as one of the planetary gears 702, 703, 704 passes through measurement point 12 of sensor 10 in array 800. These signal portions ! are referred to below as high amplitude regions 702Λ, 703 A 704À, which may comprise high peaks.

amplitude 901. It can also be shown that the total number of cores 901, 902 in the sign on a revolution of the rotating axis 80 I, that is, during the time period Tpj.v is directly correlated to the number of teeth on the circular crown 705 For example, if the number of teeth on the circular crown 705 is A - 73, the total number of peaks in the signal over a period of time T _REV will be 73, or if the number of teeth on the circular crown 705 is A - 75, the total number of peaks in the signal over a period of time I rkv will be 75, etc. This has been shown to be true, as long as there are no errors or failures in gears 702. 703, 704, 705 of arrangement 800.

H) Figure 26 illustrates an example of a part of the high amplitude region 702A of the signal shown in Figure .25. This portion of the signal can be generated when the planetary gear 702 passes through its closest position mechanically to the measurement point, sensor 12 and sensor 10 (see Figures 23-24). It has been observed that small periodic disturbances or 15 vibrations 903, which are illustrated in Figure 26, can sometimes occur. Here, minor periodic disturbances 903 have been associated with the occurrence of errors * faults or cracks in the bearings 7A as shown in Figures 23-24, which can be mounted to one of the 80IA movable arms. Small periodic disturbances 903 can * thus propagate (or transfer) from 20 of a bearing 7A through planetary gear 702 of the epicyclic gear system 700, to the crown, circular 705, where small periodic disturbances 903 can be captured by sensor 10, as described above, for example in connection with Figures 1-24. Likewise, errors, faults or cracks in bearings 7B or 7C mounted on one of the movable arms 25 801B or 801C can also generate such small periodic disturbances 903 that, in the same way as above, can be captured by the .1.0 sensor. It should also be noted that small periodic disturbances 903 can also emanate from errors, faults or cracks in the 7F bearings that can be mounted to the rotating shaft 803. The detection of these small /

periodic disturbances in the signal could be an indication that the bearings 7A, 7B, 7C and / or 7F start to deteriorate, or indicative of being at the limit of their active life. This can, for example, be important, as it can help to predict when the epicicylic gear system 700 and / or arrangement 800 is in need of maintenance or replacement.

According to an embodiment of the invention, condition analyzer 290 in evaluator 2.30 of the analysis apparatus 14 can be arranged to detect these small periodic disturbances 903 in the signal received from sensor 10. This is made possible by the embodiments 10 described above. of the invention. Small periodic disturbances 903 can also be referred to as shock pulses 903 or vibrations 903. According to an embodiment of the invention, the analysis apparatus 14 employing an intensifier 320, as described above, allows the arrest of these shock pulses 903 or vibrations 903 from bearings 7A 15 (or 7B, 7C or 7F) using a sensor 10 mounted on the ring gear 70S, as described above, although the mechanical shock pulse or vibration signal picked up by sensor 10 connected to the ring gear 705 may be weak, the provision of a 320 elevator, as described above, makes it possible to monitor the condition of bearings 7A (or 7'B, 7C or 7F) even if the mechanical shock pulse or vibration signal has if propagated through one or more of the planetary gears 702, 703 or 704,

As mentioned earlier and shown in Figures 7-9, condition analyzer 290 can be arranged to perform adequate analysis, by operating on a signal in the time domain, or a signal in the frequency domain. However, the detection of small periodic disturbances 903 in the signal received from sensor 10 is more appropriately described in the frequency domain, as shown in Figure 27,

Figure 27 illustrates an exemplary frequency spectrum of a signal comprising a small periodic disturbance 903.

as shown in Figure 26. The frequency spectrum of the signal comprises a peak 904 at a frequency that is directly correlated with the engagement of the teeth of planetary gears 702, 703, 704 and the circular crown 705. Indeed. the peak frequency of 904 in the 5 frequency spectrum will be located in A x D, where

A is the total number of teeth in the circular crown 705, and

Ω is the number of revolutions per second along the rotating axis

801, when rotation 802 occurs at a constant speed of rotation.

In addition to the peaks 904 in the frequency spectrum, the small periodic disturbance 903, as illustrated in Figure 26, can generate peaks of 905, 906 at frequencies f, i3 centered around peak 904 in the frequency spectrum. Peaks 905, 906 at frequencies f _s , f ·> can thus also be referred to as a symmetrical side band around central peak 904. According to an exemplary embodiment of the invention, condition analyzer 290 can be arranged to detect the one or more peaks in the frequency spectrum and thus be arranged to detect small periodic disturbances in the signal received from sensor 10. I could also demonstrate that peaks 90S, 906 at frequencies fi, fi refer to the central peak 904 according to equations Eq.l-2:

fj - (AXA) - (Z _;; Xf _ii5 , <(Eq. 1) f> ·· f ΑχΩ) -v (fn xf -.o-, (Eq. 2), where

A is the total number of teeth in the circular crown705;

Π is the number of revolutions per second through the rotating axis

80.kef _D is a repetition frequency of repetitive signal signature that can be indicative of a deteriorated condition; and FO;; it is the number of revolutions per second for the planet 702 around its own center.

The repetition frequency f-> of the repetitive signal signature is indicative of one of the rotating parts that is the source of the repetitive signal signature. A, repetition frequency f _n of the repetitive signal signature can also be used to distinguish between different types of deteriorated conditions, as explained above, for example, in connection with Figure 5 8. Consequently, a detected repetition frequency of the signature of repetitive signal can be indicative of a fundamental train frequency (FIT), a ball turning frequency (BS). an outer track frequency (OR), or an inner track frequency (IR) relative to a 7A, 7B, 7C or 7F bearing in the epicyclic gear system 700 in the 10 800 arrangement in Figure 24.

Thus, as described above, a data signal representing mechanical vibrations emanating from the rotation of one or more axes, such as, rotary axis 801 and / or rotary axis 303 (see Figures 23-24), may include multiple repetitive signal signatures. , and a given signal signature 15 can thus be repeated a number of times per rotation of one of the monitored axes. In addition, several mutually different repetitive signal signatures may occur, where mutually different repetitive signal signatures may have mutually different repetition frequencies. The method for intensifying repetitive signal signatures on signals, as described above, advantageously allows the simultaneous detection of many repetitive signal signatures having mutually different repetition frequencies. This, advantageously, allows the simultaneous monitoring of several headstands 7A, 7B, 7C, 7F associated with different axes of

80.1, 803 using a single detector 10. Simultaneous monitoring also 25 can use the feel that the size of solar gear 701 and planetary gears 702, 703, 704, are normally of different sizes, which additionally can allow easy detection which of the bearings 7 A, 7B, 7C, 7.F in Figures 23-24 is generating the small periodic disturbance 903. and, thus, which of the bearings 7 A, 7B. 7C. 7F in Figures 23-24 may be in need of maintenance or replacement. The method for intensifying repetitive signal signatures on signs, as described above, also takes advantage, it is possible to distinguish between, for example, an inner bearing track damage signature and an outer bearing track damage signature one a single measurement and analysis session.

The relevant value for Π. representing the speed of rotation of planetary gears 702, 703, 704, can be indicated by a sensor 420 (see Figure 24). The 420 sensor can be adapted to generate a signal indicating the rotation of the 803 axis in relation to the circular crown 705 and, from this signal, the relevant value for Q can be calculated when the number of teeth in the circular crown 705, from planetary gears 702, 703,

704 and solar gear 701 are known.

Figure 28 illustrates an example of a portion of the exemplary signal shown in Figure 25. This example portion 15 demonstrates another example of an error or failure than the condition analyzer

290 can also be arranged to detect in a manner similar to that described above. If a tooth in one or more of the gears 701, 702, 703, 704,

705 breaks or is substantially worn, condition analyzer 290 can be arranged to detect that a tooth is broken or worn, as this will also generate periodic disturbance, that is, due to the lack of fit or tooth engagement missing or worn. This can be detectable by the condition analyzer 290, for example, in the frequency spectrum of the signal received from sensor 10. It should also be noted that this type of error or failure can be detected by the condition analyzer 290 in any type of gear and / or gear system. The frequency of this type of tooth-fitting error, or gearing error, in a gear and / or gear system, is often located at a significantly higher frequency than, for example, the frequencies f ₅ , f> in Figure 27 .

101

Figure 29 further illustrates an embodiment of a condition analysis system 2 according to an embodiment of the invention. Sensor 10 is physically associated with a machine 6, which may include a 7X gear system and several rotating parts (see Figure 1 and Figure 5 29). The gear system of Figure. 29 can be the 70üda epidical gear system Figure 24. The 7 <X) epicyclic gear system can, for example, be used as a gearbox for wind turbines.

The sensor unit 10 can be a shock pulse measurement sensor adapted to produce an analog signal S £ a including a vibration signal component dependent on a vibrating movement of a rotatingly moving part in the gear system 71) 0. The .10 sensor dispenses with the analog signal $ ε _λ for a 920 signal processing arrangement.

The signal processing arrangement 920 may include a sensor interface 40 and a data processing means 50. The interface

1.5 of sensor 40 includes an A / D converter 44 (Fig. 2 A., Fig. 2B) generating the digital measurement signal S _MD . The A / D converter 44 is coupled to the data processing medium 50, so as to dispense digital measurement data signal Smh to the data processing medium 50.

Data processing means 50 is coupled to user interface 102. User interface 102 may include user input means 104 allowing a user to provide user input. This user input can include a selection of a desired analysis function 105, 290, 290T, 290F (Figure 4, Fig. 7, Fig. 8), and / or the settings for the signal processing functions 94, 250, 310, 470, 25 470a, 470, B. 320, 294 (See end 4. Fig. 30).

User interface 102 may also include a display unit 106, as described, for example, in connection with figure 2A Fig. 5.

Figure 30 is a block diagram illustrating the parts of the signal processing arrangement 920 of Figure 29. together with the user interface .102, 104 and display 06.

The sensor interface 40 comprises an input 42 for receiving an analog signal $ _ΕΛ from a sensor 10, and one. A / D converter 44.

A signal conditioner 43 (Fig. 2B) can optionally also be provided. The sensor can be a shock pulse measurement sensor. The A / D converter 44 samples the analog signal received with a certain sampling frequency f _s , so as to dispense a digital measurement data signal S _M n having a. certain mentioned sampling frequency f _; ,

The sampling frequency fS can be adjusted to fs ~ k * where k is a factor having a value greater than its 2.0

Consequently, the k factor can be selected for a value greater than 2.0. Preferably, the k factor can be selected for a value between 2.0 and 2.9, in order to avoid serrated effects. Selecting the k factor for a value greater than 2.2 provides a safety margin against the effects of knurling, as mentioned above in this document, Tutor K. can be selected for a value between 2.2 and 2.9, mute to provide the mentioned safety margin, avoiding unnecessarily generating many sample values. According to one embodiment, the k factor is advantageously selected so that 100 * k / 2 results in an integer. According to an embodiment of the factor k can be defined as 2.56, Selection of k for 2.56 results in .10 (1 * k ~ 256 ~ 2 raised to 8,

According to one. mute the frequency of atnoslragem of the digital measurement data signal S could be fixed to a certain value f _s , such as f ç ^::: 102.4 kHz

Thus, when the sampling frequency h is fixed at a certain value Ç, the frequency fstxmsx of the analog signal S _p .a will be:

fS / k, where f SEA ^ sx is the highest frequency to be analyzed on the sampled signal.

Thus, when the sampling frequency D is fixed at a value of 1.02.4 kI4z, and the k factor is defined as 2.56, the maximum frequency of fo. ^ ,. _iy da of the analog signal Sx-λ will be:

Íslvw; IW '··' · 102 400 / 2.56 - 40 kHz

The digital measurement data signal S md having sampling frequency Q is received by a filter 240. According to an embodiment of the invention, filter 240 is a high-pass filter with a short frequency of fi, _f ·. This embodiment simplifies the project, by replacing the bandpass filter, described in connection with Figure 6, with 240 highpass filter. The cutoff frequency jx of the high frequency filter 240 is selected to approximately the lowest value. expected frequency of mechanical resonance f _RMÍÍ value of the resonance measurement sensor Pulse shock 10. When the frequency of mechanical resonance f _K ^ is between 30 kHz and 35 kHz, the pass-aka filter 240 can be designed to have a frequency of lower cone f 30 kHz. The high-pass filtered signal is then passed to rectifier 270 and low-pass filter 280.

According to one. embodiment, it would be possible to use sensors 10 with a resonant frequency somewhere in the range of 20 kHz to 35 kHz. To achieve this, the high frequency filter 240 can be designed to have a lower cutoff frequency Qc - 20 kHz.

The output signal from digital filter 240 is fed to a digital envelope 250,

While prior art analog devices for generating an envelope signal in response to a measurement signal use an analog rectifier that inherently leads to a bias error being introduced into the resulting signal, the digital encoder 250 will advantageously produce a

104 true rectification without polarization errors. Consequently. the digital envelope signal S _E ^ v will have a good signal-to-noise ratio, since the sensor being mechanically resonant in the resonance frequency in the passband of the digital filter 240 leads to a high signal amplitude. In addition, the signal processing that is being performed in the digital domain eliminates added noise and eliminates added polarization errors.

In accordance with an embodiment of the Invention, optional low-pass filter 280 in the envelope 250 can be eliminated. Indeed, the optional low-pass filter 280 in the .250 envelope is eliminated, since decimator 310 includes a low-pass filter function. Thus, the envelope 250 of Figure 30 effectively comprises a digital rectifier 270. and <} signal produced by the digital rectifier 270 is dispensed to the integer decimator 310, which includes low-pass filtering.

The integer decimator 310 is adapted to perform a decimation of the digitally encoded signal Sr \ v, so as to provide a digital signal Sko> reading a reduced sample rate F§r; such that the output sample rate is reduced by an integer factor M, compared to the input sample rate f _s .

The value of M can be adjusted depending on a detected rotation speed. ('.) Decimator 310 can be adjusted to make one. selected decimation Μ: I, where M is a positive integer.

The value M can be received on a port. 404 of decimator 310. The entire decimation is advantageously carried out in several steps using low-pass filters with finite impulse response, where each FIR filter is adjustable 25 to one. desired degree of decimation. An advantage associated with performing decimation on multiple filters is the fact that only the last filter needs to have a steep ramp. A steep ramp FIR filter must inherently have different taps, that is, a steep FIR filter must be a long filter. . The number of FIR leads is an indication of (05

1) the (amount of memory required to implement the filter,

2) ο number of calculations required, and

3) the amount of filtration that the filter can leisure; in fact, more derivations means greater drag band attenuation. .Less of more drag band attenuation means, less ripple, narrower filters, etc. Thus, the smaller the filter, the faster it can be executed by the DSP 50. The length of an HR filter is also proportional to the degree of decimation achievable. Therefore, according to an embodiment of the integer tiller, the decimation is performed in another 1.0 of two steps.

According to a preferred embodiment of integer decimation it is carried out in four steps: M1, M2, M3 and M4. The total decimation M is equal to Ml * M2 * M3 * M4. This can be achieved by providing a bank of different FIR filters, which can be combined in several 15 combinations to achieve a desired total decimation M, According to one embodiment, there are eight different FIR filters in the bank.

Advantageously, the maximum degree of decimation in the last, 4 *, stage, is five (M4 ^:::: 5). providing a reasonably short filter having only 201 taps. In this way, the FIR filters in steps 1.2 and 3 may be allowed to have an even smaller number of leads. In fact, this allows the filters in steps 1, 2 and 3 to have 71 leads each, or less. In order to achieve a total decimation of M - 4000, it is possible to select the three FIR filters pro vendes decimation Ml 10, M2 ~ 10 and M3 ··· 10, and the FI.R filter providing M4 ~ 4 decimation. 25 sample exit rate _; « _S '·''· 25.6, when f _s ·“ 10'2.400 I did. and a frequency range of 10 Hz. These four FIR fikros will have a total of 4 (4 leads, and the resulting drag band attenuation is very good. In fact, if the decimation of M ~ 4000 was done in just one step, approximately 160,000 taps would be required to obtain a bandwidth attenuation

106 equally good drag ..

The output 312 of the entire decoder 310 is coupled to the fractional decoder 470 and an input of a selector 460. The selector allows a signal selection to be input to the intensifier 320.

When monitoring the condition on a rotating part, with a constant speed of rotation, the selector 460 can be placed in position to dispense the signal! Sred having sampling frequency for input 315 of intensifier 320, and fractional decoder 470 can be disabled. When condition monitoring is performed on a rotating part * with a variable speed of rotation, fractional decoder 470 can be activated and selector 460 is placed in position to dispense the Srpo2 signal having sample frequency d.e Fsr? for the 31.5 input of the 320 intensifier.

The fractional decoder 470 can be realized by the fractional decoder 470b, 94. including an adaptable FIR filter 668, as described in connection with numbers 20, 2.1 and 22 and Fig. 4.

The fractional decoder 470 is coupled to dispense a decimated signal Sredí having the lowest sample rate f to selector 460, so that when the condition analyzer is set to monitor a machine with variable speed of rotation, the output of the fractional decoder 470b is dispensed to the intensified? ' 320.

Intensifier 320, 94 can be realized as described in connection with figures 10A, 10B, 11, 12 and 13 and Fig. 4. The measurement signal input to the mixer 320 is the signal (see Figure 30), which is also illustrated in Figure 11 as having sample values leoMmsoxru θ signal Ssnjo is also referred to as I and 2060 in the description of figure 11. The processing signal of the instrument involves discrete autocorrection for the discrete input signal S According to an embodiment. the intensifier works in the time domain in order to achieve autocorrelation

107 discrete for the discrete input signal S Thus, according to this embodiment, nau intensifier signal processing does not include the Fourier transformation nor does it include any fast Fourier transform. The output signal O. also known as S ^ nr, is illustrated in Figures 12 and 13.

The measurement signal S to be input to the intensifier, can include at least one vibration signal component Sj) of the said rotatable mobile part; where said vibration signal component has a repetition frequency of F _r > which depends on the rotation speed ik-n of said first part. A, 10 repetition frequency f _{) of signal component So can be proportional to the rotation speed f _ROT of the monitored part in rotation.

Two different damage signatures SD1, SD2 can have different frequencies Fdl, fd2 and still be reinforced, that is, SNRimproved, by the intensifier. So, the intensifier 320 is advantageously adapted to intensify different signatures Sn? having mutually different repetition frequencies f _{> 5} and 9-. Both fry repetition frequencies. ef >>.> are proportional to the rotation speed f of the monitored rotating part, while ή>; is different from fpj (f _s > ₅ <> This can be expressed mathematically as follows:

FDLkl- P e

FD2 ·· - k2 * f _SOK where kl and k.2 are positive real values, and kl <> k2, and kl or greater than or equal to one (I), and k2 greater than or equal to one (1)

The intensifier dispenses an output signal sequence for a 290T time domain analogue input. so that when a user selects, through the 102,104 user interface, to perform an analysis in the time domain, the time domain analyzer 290T, 105 .108 (Figure 30 & Figure 4) executes the selected function 105 and dispenses relevant data for screen 106. a plus with iutensiilcador 320 is that it does not require an output signal in the time domain, so condition monitoring functions 105, 290T requiring an input signal in the 5 time domain can be configured to operate directly over the signal values of the signal output illustrated in Figures 12 and 13,

When a user selects, through the 102 J 04 user interface, to perform an analysis in the frequency domain, the intensifier will dispense the output signal sequence for Fast Fourier Transformer 294, and 10 the FFTransformer will dispense the resulting frequency domain data for the 290F, 105 frequency domain analyzer (Figure .30 & Figure 4). The 290F, 105 frequency domain analyzer will perform the selected function 105 and dispense relevant data for screen 106.

In the embodiment of the invention shown in Figures 29 and 15 30, it is advantageously easy for a user to perform an analysis employing the head unit and the fractional decimator. As illustrated in Figure 30, user interface 102, H14, 2413 cooperates with a parameter controller 930 adapted to provide configurations for arrangement 9.20. Figure 31 is a schematic illustration of parameter controller 930

The lower is an example of parameter settings:

To perform an analysis in the frequency domain, the user must enter the following data via the user interface 10.2,104,24B:

1) Information indicative of the frequency of repetition in the Interest. The repetition frequency% is the repetition frequency of an SD subscription of interest. This information can be entered at the bottom of a frequency or in the form of a number indicating the highest frequency of repeated SD damage signature of interest.

2) Information indicating the desired improvement of the SNR value for, signature of repetitive signal S _r> . This information can be entered into the

109 form of L value of intumifier. SNR The SNR booster value 1 .. is also discussed below, and in connection with figure loA above.

3} Information indicating the desired frequency resolution, on FFT 294, when it is desired to perform an FFT of the 5 intensifier signal output. this can be defined as frequency compartments of Z value. According to an embodiment of the invention, the Z frequency resolution is adjusted by selecting a Z value from a group of values. The group of selectable values for, the frequency resolution can include Z - · 400

Z-800

Z. - 1600

Z - 3200

Z - 6400

Thus, although signal processing is quite complex, arrangement 920 was designed to provide an advantageously simple user interface in terms of information required by the user. When the user enters or selects values for the three parameters above, all other values are automatically adjusted or predicted in the array920.

The SNR Intensifier I.

The signal to be input to the intensifier may include a vibration signal component dependent on a vibratory movement of the rotatingly mobile part; where the aforementioned, vibrating signal component has a repetition frequency Ira. which depends on the speed of 25 rotation f _Kf > ·: · of said first part; said measurement signal including noise, as well as said vibration signal component so that said measurement signal has a first signal-to-noise ratio with respect to said vibration signal component. The intensifier produces an output signal sequence (O) having components

Repetitive signal HO corresponding to said at least one vibration signal component so that said signal output sequence (O) has a second signal-to-noise ratio value with respect to said vibration signal component. It was established, by means of measurements, that the second signal / noise ratio value is significantly higher than the first signal / noise ratio when the L value of SNR inteasifier is set to one (1) <

In addition, it was established, through measurements, that when the L- do value intensified! of SNR is increased to L ··· 4, then the resulting SNR value no in relation to the mentioned vibration signal component in the output signal is doubled compared to the SNR value associated with L '1. Increasing · if L value of the intensified! from SNR to L-10 appears to result in an improvement of the associated SNR value by a factor 3 for the vibration signal component in the output signal, compared to the SNR value for the same input signal when 1. ~ k

Thus, when the L value of the SNR magnetizer is increased from L <~ 1 to L>, the resulting SNR value can be increased by the square root of k ₂ .

In addition, the user can enter an adjustment to have the 920 arrangement continuing to repeat the measurement. The user can configure it 20 to repeat the measurement with a certain repetition period Tp _M. that is, always start a new measurement when the time TRm has elapsed. Ί ' ₅ > μ can be established as one week, one hour, or ten minutes. The value for selecting this repetition frequency depends on the relevant measurement conditions.

As the densifying method requires a lot of data input values, that is, the number of sample input values can be high, and is suitable for measuring parts in slow rotation, the measurement duration will sometimes be quite long. Thus, there is a risk that user settings for the frequency of repeat measurements are incompatible

111 with the duration of measurements. Therefore, one of the steps performed by arrangement 920, immediately after receiving input from the above user, is to estimate the expected duration of T _M measurements.

The duration T m c:

I M ICOMCRSMKVUy R ^ j,

Where IcoMparacNTo is the number of samples in the signal to be entered in the probe to obtain the measurements according to the settings selected by the user as defined below, and is as defined below.

The 920 array is also adapted to compare the duration of the Tm measurements with the repetition period value Tp _M as selected by the user. If the repetition period value Trm is less or almost the same as the expected duration of measurements, a parameter controller 930 is adapted to provide a warning indication via the user interface l02, 106 for example, by a suitable text on the display . The warning may also include a sound or a flashing light.

According to an embodiment, arrangement 920 is adapted to calculate a suggested minimum value for the repetition period value depending on the calculated estimate of the duration of measurements Tm

Based on the above user settings, parameter controller 930 of the 920 signal processing arrangement is able to set all parameters for signal processing functions 94 (Figure 4). that is, entire decimator settings and intensifier settings. In addition, the 930 parameter controller is able to set all parameters for the fractional decimator when necessary. The parameter controller 930 is able to set the parameter for FFT 294 when a frequency analysis is desired.

The following parameter can be predefined in array 920 (Fig. 30): the sample frequency f _s of the A / D converter 40.44.

The following paragraph can be defined: f »hi

As mentioned above, the value of the çor parameter can be measured and stored in. association with the corresponding sample values of the S signal whose sample values are fed to fractional decimator 470b.

What are you looking for? JxxleipL5ÊL

Sample rate at the output of the i.ntensl ficador signal 320;

Fsr3 ^ C * (X * _tQ: where

C is a constant greater than 2.0,

The _¥ is the order number of user input, or calculated in response to a maximum frequency value to be monitored, as selected by the user, fi _ior is the instantaneous rotational speed measurement of rotating part while monitoring the actual condition;

Μ ~ The entire decimator value for use in decimator 310 is selected from a table with a set of predetermined values for the total integer declination., To select the most suitable M value, the parameter controller 930, (Fig, 30) first calculates a value very close to M calc - fs / fsae * f & n nur / fium ^ where f &: Í'í, r2 are defined above, and

ÍroFmin / fao-rmx is a value indicative of the response between the lowest and the highest rotation speed to be allowed during the measurement. Based on the M calc value, the selector then chooses an appropriate value M from a list of predefined values. This can be done for example by selecting the closest value M that is less than M that falls from the table mentioned above.

sample rate to be dispensed from the entire decimator 310. ísra is set to Fssrí ^:::: fj / M.

D is the fractional deductive value for fractional decimator, D can be adjusted to D tL / ísm where f _s r.í £ Qe are as defined above.

113

Ο <ΌΜΡΗ5Μ ·· .Χ · ΐ <? C * 'Z, where

C is a constant with a value greater than 2/1 such as 2.56, as mentioned above

Z is the selected number of frequency sections, that is, information indicating the desired frequency resolution in FFT 294, when you want to perform an FFT of the intensifier output signal,

Smaom OcoMpRutr.xTõ θη «m value greater than O length? where Ο ουΜΡΗίΜΕχΎο is as defined above.

koOMPRIMrM IAomfrouutq * L SsnIoso HollowMramrsm

Q - OMPR; MENT IcOMPRIMEN IO ^ ÍNÍCKJ O <? OMrtUMEN ΓΟ

SMDP (t) “the sample values of the output signal, as defined in equation (5) (See Figure 10A).

Thus, the parameter controller 930 is adapted to generate the corresponding adjustment values, as defined above, and to dispense them for the relevant signal processing functions 94 (Fig. 30 and Fig. 4).

Once an output signal has been generated by intensifier 320, condition analyzer 290 can be controlled to perform a selected condition analysis function 105. 290, 290T, 290F, via a selection signal dispensed over an input control 300 (Fig. 30). The check signal dispensed over control input 300 can be generated through user interaction with user interface 102 (See Figures 2A and 30). When the selected analysis function includes fast Fourier transform, analyzer 290F will be defined by the selection signal 300 for Q | jerar over an input signal in the frequency domain,

The FF 294 Trartformer can be adapted to perform the fast Fourier transform on an input signal received with a certain number of sample values. It is advantageous when the certain number of sample values is defined as an even integer, which can be divided by two (2), without resulting in a fractional number.

114

According to an advantageous embodiment of the invention, the number of samples Ο ^, μ ^ μκμο in the output signal of the amplifier is established depending on the frequency resolution Z. The relationship between frequency resolution and Z the number of samples (WwiNm at the intensified output signal? Is:

OcoMtwMBXTOi ™ k Z, where

Hollow.mprlmsnto is the number of samples of sample values in the signal dispensed from the intensified? 320;

k is a factor having a value greater than 2.0.

Preferably, the k factor can be selected for a value between .2.0 and 2.9, in order to provide a good safety margin, avoiding generating unnecessarily many sample values.

According to one embodiment, the k factor is advantageously selected so that 100 * k / 2 results in an integer.

This selection results in values for O <x> su * rími?> Ítí> adapted to be suitable as input for the FFTransformer 294. According to one embodiment, the k factor can be adjusted to 2.56. Selection of k for 2.56 results in 100 * k 256 2 raised to 8.

Table A shows examples of user-selectable frequency resolution Z values and corresponding values for

UcOMPRlMENIO '

k Z θΟΟ.ΜΗΟΧΦ-.ΜΤ 2.56 400 1024 2.56 800 2048 2.56 1600 4096 2.56 3200 8192 2.56 6400 16384 2.56 12800 32768 2.56 25600 65536

labels A.

An embodiment of the invention relates to an apparatus for analyzing the condition of a machine having a first part which is rotatable movable at a speed of rotation with respect to a second machine part; the mentioned device including:

a sensor for monitoring said moving part, so as to generate at least one analog measurement signal, including at least one vibrating signal component dependent on a vibrating movement of said rotatingly moving part; wherein the vibration signal component mentioned has a repetition frequency _(U;. which depends on the rotation speed (Qor) of said first pane, the said measurement signal including noise, as well as the aforementioned vibration signal component so that said measurement signal has a first signal-to-noise ratio value with respect to said vibration signal component;

an A / D converter (40, 44) for generating a digital measurement data sequence in response to said measurement signal; the aforementioned digital measurement data (Smu) sequence having a first sample rate (i ' _s ):

a first digital filter (240) for performing digital filtering of the digital measurement data sequence (Smí >> d «in order to obtain a filtered measurement signal (S *. ·), an envelope for generating a first digital signal ( Sknv. In response to the filtered measurement signal (Siam decimator for performing a decimation of the first digital signal (S ^ nv, Smu?; ·), In order to obtain a digital decimated signal (Sar-m. Having a reduced sampling frequency (f'A 1'smK the mentioned decimator (470.470a, 470b) having:

116 a first input for receiving said first digital signal (S _f ; _NV , ^c a second input for receiving a signal indicative of said variable speed of rotation (fb _{! N} a third input for receiving a signal indicative of adjustment signal outgoing sample rate;

said decoder (470, 470a, 470b) being adapted to generate the said digital signal e-scraped (Sr ^ x depending on the said first digital signal! (Smo. & r.cvX said signal! indicative of the mentioned rotation speed (Iwvn o said signal indicative of an output sample rate adjustment signal, where said decoder (470, 470a. 470b) is adapted to generate said digital dimmed signal (S rhO so that the number of sample values per revolution of said rotating part is kept at a substantially constant value when said speed of rotation varies, and a reinforcer (320) having an input to receive said signal, digitize and scale (Sr _E d _): said intensifier being adapted to produce a output signal sequence (O) having repetitive signal components corresponding to the said at least one vibration signal component so that the said, output sequence signal (O) has a second value of the synabruated ratio with respect to said vibration signal component; said 25 second sin-to-noise ratio value being greater than said first sinabruised ratio value, and an analyzer (105, 290, 290T, 294, 290F) to indicate a machine condition dependent on said vibration movement of the said routinely moving part in response to the aforementioned sequence of

H7 signal output l (O). This solution advantageously provides a very thin solution, as it minimizes the complexity of files while obtaining significant performance improvement

According to an embodiment, the first digital filter 5 (240) is a high-pass filter with a cut-off frequency.

According to one embodiment, the shock pulse measurement sensor (10) is resonant, having a resonant frequency value (f ^) _: the high cut-off frequency of the high-pass filter 240 is selected 10 for a value less than the mechanical resonance frequency value (f r.mu) of the Resonant Shock Pulse measurement sensor (10).

According to an embodiment, the envelope (250) comprises a digital rectifier (270), and where

Said decimator (310) is coupled to receive signal 15 to be decimated from an output of said rectifier (270), and where said decimator (310), which includes low-pass filtering Λ elimination of low-pass filter components in the filter stage and in the envelope leads to a simplified design. In addition, due to the use of a resonance sensor, the need to level filters 20 is also eliminated.

According to an embodiment, the decimator includes an integer decimator (310) adapted to perform decimation by an integer M; where the M value is automatically adjusted depending on the aforementioned speed of rotation (f _RiH )

According to one embodiment, the integer decimator includes several finite impulse response low-pass filters.

According to one embodiment, each FIR filter is adjustable to one. desired degree of decimation.

118

According to a realization morin, the integer decimator includes a lamer) of different ml FIR filters that the various filters between the mentioned filter bank can be combined to obtain a desired total definition M.

According to an embodiment of the F1R filter bank it includes more than three filters.

According to an embodiment, an output (312) of said integer decimator (310) is coupled to an input of a fractional decimator (470) and to a terminal of a selector (460); said selector having another terminal; the said other terminal being coupled to a said said fractional decimator (470), and a third terminal of said selector (460) being coupled to the input of said intensified? ' (320).

According to one embodiment, there is a computer program to have a computer analyze the condition of a machine having one. part rotating kmt, the computer program comprising:

computer-readable code means? ' which, when executed on a computer, causes the computer amostre an analog measurement signal at a sampling frequency _(f;. in order to generate a digital measuring data sequence (Smdj cm response to analog measurement data received;

computer readable code means that, when executed on a computer, & z with the computer performs a condition analysis function (FI, F2, Fn) to analyze the condition of the machine depending on the aforementioned digitally encapsulated signal (S ^ y S *

According to an embodiment, the computer program product comprising a computer-readable medium; c a computer program, as defined above,

119 said computer program being recorded on said computer-readable medium.

One aspect of the invention relates to an apparatus for analyzing the condition of a machine by reading a first part which is totally movable at a speed of rotation with respect to a second part of the machine, where the apparatus includes:

a sensor for monitoring said moving part in order to generate at least one analog measuring signal including at least one vibrating signal component dependent on a vibrating motion 10 of said rotating moving part: where the said vibrating signal component has a repetition frequency (f which depends on the rotation speed (Q-ο) of said first part; said measurement signal including noise, as well as said vibration signal component so that said measurement signal has a first value signal-to-noise ratio 15 with respect to said vibration signal component, and an A / D converter (40.44) to generate a digital measurement data sequence in response to said measurement signal; digital measuring instruments (S _W ))> having a first sample rate tf Q.

The apparatus also includes a reinforcer (320) having an input to receive the said digital signal, ($ κεο>. The iutensificadur is adapted to produce an output signal sequence O having repetitive signal components corresponding to that mentioned by the menus a component of vibration signal, so that the aforementioned, that the output signal sequence 25 has a second signal-to-noise ratio value with respect to said vibration signal component; said second signal-to-noise ratio value being higher than mentioned first signal-to-noise ratio value. The apparatus also includes a 105, 290, 290T, 294, 290F display to indicate a condition of the machine dependent on said vibrating movement of said moving part in response to said signal sequence about to leave ().

An embodiment A2 of the apparatus according to aspect ΛΙ further includes a parameter controller 930: said parameter controller 5 being adapted to cooperate with a user interface 102. 104, 106 to adjust control parameters of said apparatus, in order to adapt functionality 94. 310, 470, 320, 294 dependent on user input via the mentioned interface; where said device is adapted to request adjustment information via the aforementioned user interface 102, 1.04, 106.

An embodiment A3 of the apparatus according to embodiment A.2 of the apparatus, where said information requested includes information indicative of a frequency range to be monitored for detection of said signature (S having said repetition frequency

An A4 embodiment of the apparatus according to. the embodiment realização2. where the mentioned information requested includes information indicative of the highest repetition frequency (f _D5 of interest.

A Λ5 embodiment of the chord apparatus? with embodiment A2, where said requested information includes information indicative of a desired degree of improvement of the second noise-to-noise ratio value.

An embodiment A6 of the apparatus in accordance with embodiment A.2, where the aforementioned requested information includes information indicating a desired frequency resolution for a fast Fourier transform.

An embodiment A7 of the apparatus according to embodiment A2, where the aforementioned requested information includes information indicating an adjustment to have the arrangement 920 repeat the measurement with a certain repetition period Tp _M

An embodiment z \ 8 of the apparatus according to any of the embodiments A2, A3, A4, Λ5, A 6 or A7, where the apparatus is adapted to provide a warning indication 5 via the user interface 102.106 if the repetition period value T pm entered by the user is shorter or has approximately the same expected duration of Ty measurements.

An embodiment of the invention A9 relates to a method for analyzing the condition of a machine having a rotary axis, method 10 comprising:

receive a digital input signal (í) having a first plurality (1 comptumfnio) of sample values, the said digital input signal (l) representing the mechanical vibrations emanating from the said rotary axis to the point of causing the occurrence, of a vibration 15 having a repetition period (T _R5; perform a correlation in said intensifier in order to. produce an output signal sequence O where repetitive signal amplitude components are amplified in relation to the cstoeásfko signal components;

generate a digital output signal O having a second plurality of samples, said second plurality of samples being a positive integer and less than the mentioned first plurality (IroswiMsnu) ~

An embodiment of A 10 of the method according to the 25: embodiment of .A% where n received digital input signal (!) Includes signal components from a deteriorated condition, said deterioration signal components being repetitive with the mentioned repetition period (T

A mutation A1 of the method according to embodiment A9 or A10, under which the aforementioned deterioration signal components are hidden by the noise in said digital input signal I.

> An aspect .8 of the invention relates to a method for analyzing the condition of a machine having a rotary axis, comprising: receiving a digital input signal l having a first plurality of sample values, the said digital input signal I _s that represents the mechanical vibrations emanating from 10 rotation of the mentioned axis to the point of causing the occurrence of a vibration having a repetition period I \.

splitting the received digital signal I into a first signal portion 2070 and a second signal portion;

generating a digital output signal O having a second plurality 0 <. new sample samples, a. The second plurality mentioned is UeoMíPWMENTO being a positive integer and less than the mentioned first plurality Vrmrconono: the said digital output signal O being generated in response to the first signal portion 2070 and the second signal portion

An embodiment 132 of the method according to the aspect, where the received digital input signal I includes signal components emanating from a deteriorated condition, said deterioration signal components being repetitive with the said repetition period Tr.

An embodiment 83 of the method according to embodiment 82, where said deterioration signal components are hidden by the noise in said digital input signal 1,

A muting embodiment B4 of the method according to embodiment B 1, B2 or B3, where the digital output signal O is generated in such a way that the repetitive signal amplitude components are amplified.

An embodiment 85 of the method according to any of the embodiments B 1, 82, B3 or B4, where an increase in the amount of rotation of said axis causes an increase in the number of repetitions of occurrence of said repetitive signal amplitude components and said method 10 further comprises generating the digital output signal O in such a way that an increase in the first plurality of sample values allows for a greater degree of amplification of said repetitive signal amplitude components.

An embodiment B6 of the method according to any of embodiments 81, 82, 83. B4 or B5, further comprising receiving an indicative value of one. lowest repetition rate of a vibration to be detected, determine a minimum value for the second plurality of 20 samples Length in response to the mentioned value indicative of the lowest repetition rate.

An embodiment B7 of the method according to embodiment B6, further comprising calculating an estimated duration of measurements to cause the axis to perform the said minimum amount of rotation, so as to allow the deformation of any vibration having the aforementioned minor repetition rate.

An embodiment B8 of the method according to any of embodiments 81, 82. B3, 34, B5 B6, or 87, further comprising allowing a user to select a desired amount of signal component amplification! deterioration;

calculating a value for the first plurality of digital input signal sample values in response to the mentioned desired amount of amplification,

One aspect of the B9 invention relates to a method for analyzing the condition of a machine having a rotary axis, comprising:

receiving a digital input signal l having a first plurality l'eoMi <pjMr.rrro of sample values, said digital input signal 10 representing the mechanical vibrations emanating from the rotation of said axis, during a period of time:

split the input signal type! received I and that in a first portion of signal 2070 and a second portion of signal; said first portion representing a first time duration of the received digital input signal 1, and said second portion representing a second time duration of the input signal received digtta.l I, said first time duration being different from that mentioned second temporal;

generate a digital output signal O having a second plurality O _C sample length, the aforementioned second plurality bfcoMpRiMsxro being a positive integer and less than the first mentioned, plurality Ιοο ^ &μενίο; where the generation of a sample value O (1) in the digital output signal O is performed in the time domain.

A B 10 aspect of the invention relates to a method for analyzing the condition of a machine by reading a rotary axis, comprising:

receiving a digital input signal I having a first Ictimprímexu ·· »plurality of sample values, said digital input signal I. representing the mechanical vibrations emanating from the rotation of said axis during a period of time;

dividing the received digital input signal I into a first portion of signal 2070 and a second portion of signal, correlating the first portion of signal 2070 with the second portion of signal in order to produce one. output signal sequence O, where the amplitude components of repetitive sites are amplified in relation to the stucco signal components,

One aspect B 11 of the invention relates to an apparatus for analyzing the condition of a machine having a rotating part with a speed of rotation, comprising;

a first sensor adapted to generate a measurement signal S j, _A electrical analog dependent on mechanical vibrations emanating from the rotation of the mentioned part, an analogue-digital converter 44 for sampling of said analogue measurement signal at a frequency of sampling in order to generate a digital measurement data signal> in response to the aforementioned received analog measurement data;

a first decimator for performing a digital measurement data signal deduction in order to obtain a first digital signal S max with a reduced first sampling frequency an intensifier reading an input to receive said second first digital signal Sruv; θ mentioned intensifier being adapted to receive a first plurality IcuMPRimmru of sample values, where the aforementioned first digital signal 25 S represents mechanical vibrations arising from the rotation of said piece, during a period of time;

said intensifier being adapted to divide the first received digital signal S mcx S snv into a first portion of signal 2070 and a second portion of signal;

126 the intensified mentioned? being adapted to correlate the first signal portion 2070 with the second signal portion, so as to produce a signal output sequence O where repetitive signal amplitude components are amplified relative to the stochastic signal components;

an evaluator 230 for performing a condition analysis function Π, F2, Fn to analyze the condition of the machine depending on the mentioned second digital signal Sg.n).>

Claims (2)

RE1WOCAÇÕES 1. Apparatus for analyzing the condition of a machine by reading a rotating part, with a rotation speed (f ^ m), characterized by the phallus of understanding: 5 an input (42) for receiving an analog measurement signal (Sea) indicative of a vibration signal signature having a vibration frequency (fsj .x) and a repetition frequency (G>); an A / D converter (40, 44) for generating a digital measurement signal (Smu) dependent on the analog measurement signal, said digital measurement signal 10 (Smu) having a first sample rate (f _s ), the first sample rate with the said vibration frequency being at least twice (k) an encoder (250, 94) to generate an enveloped signal indicative of the said repetition frequency (fo): 15 is a decimator (310, 94) to generate a first digital decimated signal ($ &>/.>, Shedu Sri-xu) dependent on said enveloped signal, so that said first digital signal has a sample rate reduced (í2r), an intensifier having an input to receive the aforementioned decimated signal, where the intensifier (320) operates in the time domain to perform discrete autocorrelation for the first decimated digital signal (Srh>, S ^ edu W0 in order to generate a sequence of intensifier output signal (O, ^and an analyzer (290; 2901, 294, 290.F) to perform a condition monitoring function (Fl, F2, Fn) in order to analyze the condition of the machine dependent on the aforementioned CO intensifier output signal sequence, Smur). 2. Apparatus according to claim 1, characterized by the fact that the mentioned intensifier (320) operates to perform discrete autocorrelation in a delay (S ^ c-ra Nc) for the first eeimated digital signal (‘Sruj, Sr-mn SarinX 3. Apparatus according to claim I or 2. In addition, the said intensifier is adapted to process a first plurality Ocomprmi-n'to) input sample values of said first digital signal (S _R5; , _; . \ Sreui. Smr.xv?) In order to generate an output signal sequence (O * S ^ í> r _?. Having a second plurality (O <omfrim £ r ^: to) sample values of ^the aforementioned second plurality being a positive integer. 4. Apparatus according to claim 2, characterized in that said intensiikador is adapted to process a first plurality (ia.wRiMEmo) of input sample values from the first digital signal (S ^ n Sredl SpEtat ) in order to generate a signal sequence! output (O, S ^> pX having a second plurality (OcoMFRiMhNTo) of exit sample values ^the said second plurality being a positive integer, and where the said delay (Sj \ _R ': G. bl _c l is a integer having a value equal to, or greater than, the aforementioned second plurality value (Orosr pri sum rc) · 5. Apparatus according to any one of the preceding claims, characterized in that the mentioned íntensifteador (320. 382, 386) is adapted to generate a sample value, output (soim ··) ⁱⁿ dependence of a third plurality (Qomprimenio ) of input signal products (P (it) for mentioned third plurality (CcoMFRtMEN'to) being a positive integer; said intensifier (32.0, 382, 386) additionally comprising means (365, 375. 37S.B ) to generate a value of data indicative of the aforementioned third plurality depending on an increment value (I.) of the Signal-to-Noise Ratio and data (Z, Y, i'sr. ÍroO indicative of the mentioned second 5 plurality (í \ 6. Apparatus for analyzing the condition of a machine by reading an active part, with a rotation speed (Írot) * characterized by the fact that it comprises: a first input (315) to receive a first signal 10 digital (Sued. $ I: sv) dependent on mechanical vibrations emanating from the rotation of the mentioned part; the aforementioned digital signal having a sample rate lifo) where the aforementioned first digital signal is SRD. Smd. Si-.nv) can include noise and a first signal signature (StxX with a first repetition frequency (f _m ). 15 an intensifier (320) for processing a first plurality (1 <.όμρκϊμι ^ π>) of input sample values of said first digital signal (Sreix Sm & S fnv) in order to generate an output signal sequence (O, Smd ?) having a second plurality (Ocomprímen ro) of output sample values (Smofo); the mentioned second plurality being 20 a positive integer; an analyzer (.290; 290T, 294, 290F) to perform a condition monitoring function (FI, F2, Fn) in order to analyze the condition of the machine depending on the aforementioned output signal sequence (O, SmopK where mtensi & ador (320) includes; 25 at least a second input (335, 350, 360, 364) to receive data (Z, ¥, f _RV r, OcoM.rakvrmo) indicative of the mentioned second plurality (OccuMPíuvr.xrv) has one output (394, 396. 398) to dispense with said output signal sequence (O, SmupT where said intensifier (320, 382. 386) is adapted to generate an output sample value (Sm ^ u) t $ depending on a third plurality (G. vmpíuv-x n>) of input signal products (P (i, l)) ia third plurality (C _; wi-mwO being an integer) 5 positive; where a product of the input signal (Pli, t)), for an output sample position t, is obtained by multiplying a first input sample value (I (i)) in a first sample position (fi) by a second input sample value (I (i · * t -r S to)) for the second sample position (i -t 'to mentioned second input sample value being 10 separated from the aforementioned first input sample value by a determined number (t t-S) of the sample positions, the said determined number of which is equal to or greater than a determined value the intensifier comprising, additionally: at least one third entry (335 _? 366) to receive data 15 indicative of a significant value of the Signal-to-Noise Ratio (L); and means (365, 375, 375B) for generating a data value indicative of the mentioned third plurality (Bcc \ wmrmo) depending on the mentioned incrementing value of the Sinaí-Ruldo Relationship 20 (l ..) and of the said data (zL Y, 1Q <ÍRor) indicative of the mentioned second plurality (0 <χ) μρ »» 5χΊό) < Apparatus according to claim 6, characterized in that the mentioned intensifier (320, 382, 386) is adapted for. 25 generating the said sample output value (Smdp <U P ^ for said sample output position t by adding (SI 140) the said third plurality of input signal products (P (t, t)). 8. Apparatus for analyzing the condition of a machine having a rotating part, with a rotation speed (G: n) _? characterized by the fact of understanding: a first input (315) to receive a first digital signal (Saru $ mo. Senv> dependent on mechanical vibrations emanating from the rotation of said part; said first digital signal (S ^ m) 5 having a sample rate (n , _R ) where the aforementioned first digital signal (Srhx Smd. Seny) can include noise and a first signal signature (Sn;) having a first repetition frequency (fm); an intensifier (320) for processing a first plurality (IcoMPRSMtmro) of sample input values of said first digital signal (S; um. S.mu. SxnvK of noise generating an output signal sequence (O, S ^ pr) having a second plurality (O length) of output sample values (8 MDFa?) 'the aforementioned second plurality being a positive integer; an analyzer (290; 2901 ', 294., 290F) to perform a 15 condition monitoring function (FL F2, Fn) in order to analyze the condition of the machine depending on the aforementioned output signal sequence (O, where the intensifier (320) includes: at least one second entry (335, 350, 360, 364) to receive data (Z, ¥, fs.u. Opr length) indicative of the aforementioned second plurality (O; QMrsuMcsno.K o one exit (394, 396, 398) to dispense with the aforementioned output signal sequence (O, Smdp); or the said intensifier (320, 382, 386) is adapted to generate an output sample value (Ssmrr according to the expression: >, í> í í '»νΓ, ν / νΑ \ η> 5 25 Ú) '' · Σ * ⁷ V or according to the expression:

Where Beginning ê integer with a value equal to or greater than the mentioned value of the second plurality (Oc.length) » Ccf.MPRíMFxoo is an integer; and 5 b is an integer constant; and where the intensified! additionally comprises: at least one third entry (335, 366) to receive data indicative of an incremental value of the SmabRuido Ratio (L); and means (365, 375, 375B) for generating a data value L indicative Ü said integer value Ccomprimento ⁱⁿ dependence of said incrementing value ratio SinabRuído (U and the aforementioned data (Z, Y, f $ _r. f _R0T) indicative of the mentioned second plurality (O <-. length) · Apparatus according to any one of claims 5, 6, 7 or 8, characterized by the fact that said means (375, 375B) for generating a data value indicative of the mentioned third plurality (C eoxwucmro) is adapted to receive 20 data indicative of said first plurality (1 length) ' ^and data indicative of said second plurality (OCCMHUMEN tO.l. data indicative of said determined value (Select X 25 and where said means (375, 375B) to generate a value of data indicative of said third plurality (C-length) be adapted to establish the third value of plural age equal to the difference between o vai or Ícomprimex-o 9. sum of values Symcio £ Ornxa-suMhMo · IO. Apparatus according to any of the claims 5, 6, 7 or 8, characterized by the fact that said melo (375, 375B) to generate a value of data indicative of the mentioned third plurality (CccMrarerund be adapted data indicative of the mentioned second pie data indicative of the said incrementing value of Signal-to-Noise Ratio (L). and where 10 said means. (375., 375B) to generate a data value indicative of said third plurality (G _{sV n <rer \ ud be adapted to establish the third plurality value CcoMPRiMr.Nvu jgtjal to the product of the second value plurality (Ocgmprímento) is the value that adds to the Signal-to-Noise Ratio (L). .1.5 11. Apparatus according to any of the preceding claims, characterized by the fact that the aforementioned intensified? (320) further understand: a stochastic frequency attenuator adjustment operator (370) adapted to receive data indicative of said second plurality (OroMmMimro); wherein said signal attenuator adjustment operator, of cstochastic frequency (370) adapted to establish a full data value SjNtcH; indicative of the aforementioned determined value (S ^ kao) being equal to the value of the second plurality (Oo.aípjumento) 4 «m value greater than the 2.5 value of the second plurality (Ογομρηιμεμό) · 1.2. Apparatus according to any of the preceding claims, characterized by the fact that the aforementioned intensified? (320) further understand: a Calculated? Signal Length (365) arranged to establish the first plurality (I οομηομη-οό) to a value equal to an integer ί _Γ or to a value greater than the integer h_. where I; ~ O, ovrsu.xn-mo * l * S: \? <: Of Kompkoílxío where 5 OPTIONS is an Integer equal to the aforementioned value of the second plurality; L is the mentioned incremental value of the Signal-to-Noise Ratio: e S? \; Au is the mentioned value determined. 13. Apparatus according to any one of the preceding claims, characterized by the fact that said mtensiflcador (320) comprises, additonally: an Output Signal Length Calculator (345, 340. 34SB) arranged to establish the value of the second plurality 15 (Ocomprimrnto) equal to an integer value depending on data indicative of a frequency resolution (Z) to be obtained by means of analysis of the output signal sequence (O, Smof). 14. Apparatus according to claim 13, characterized in that the aforementioned Output Signal Length Calculator 20 (345, 340, 345B) be adapted to establish the value of the second plurality (OenMHUMKNto) equal to the product of an indicative value for the mentioned resolution frequency (Z) and a constant C, where the constant-C has a value equal to 2 or a value greater than 2.0. 15, Apparatus according to claim 13, characterized 25 due to the fact: the mentioned Safda Signal Length Calculator (345, 340, 345B) will be adapted to establish the value of. second plurality (O ^ osrraíMruro) depending on data indicative of a frequency resolution (Z) to be selected by analyzing the output signal sequence (O, S ^ p): and depending on Indicative data of the mentioned speed of rotation (fork and depending on data indicative of the mentioned sample rate (Uh); and depending on data indicative of an order value (Y, O _v , Ommn). the mentioned order value being a relationship between the highest repetition frequency (fDmax) to be detected in the aforementioned output signal sequence (O. Smdp) «the mentioned speed of rotation (Írgt). 16, Apparatus according to claim 13, characterized in that said Output Signal Length Gauge (345. 340, 345B) is adapted to establish the value of the second plurality (Length) depending on the aforementioned indicative data of a frequency resolution (Z) to be obtained by analyzing the output signal sequence ((), SmdpX and depending on data indicative of the mentioned sample rate (U _K ): and depending on indicative data a higher frequency repetition (IDmax) to be detected in the mentioned output signal sequence (O, S ^ p), 17, Apparatus according to any one of claims 1 to 12, characterized in that said Output Signal Length Calcuhdor (345, 341), 34S3) is adapted to set the value of the second plurality (OcoMíRiMENrto) to a predetermined value . 18, Apparatus according to any of the claims 1 to 12, characterized by the fact that it additionally comprises a user interface (102, 104. 24Β) adapted to allow a user to enter data (Z, ¥, f _SR- f _{R <5} y. O (; <:> mprí .mento) indicative of the mentioned second plurality (() f <Aip-re.re \ r <>); where mentioned data (Z, 3 \ f ^ tt. Dar. DcoxmuMENU) 5 mentioned user interface adapted to dispense with) indicative of said second plurality (GroMPJUMEmo) for said at least one second entry (335, 350, 360, 364). 19. Apparatus according to claim 18, characterized by the feel of 10 the aforementioned user interface (102, 104, 24B) to be adapted to allow a user to establish the value of the second plurality (The co-smMsmo) · 20. Apparatus according to any of the preceding claims, characterized by the fact that it additionally comprises: 15 means for. control, the aforementioned sample rate (f _R. %, f ^ i, fsR2j. so that it matches

on what C is a constant having a value of 2 or greater 20 than 2.0, and ¥ is an order value, that is, a relationship between the highest repetition frequency (Ülmax) to be detectable in the mentioned sequence, of the output signal (O, S ^ nr) £ a mentioned rotation speed (ihor); ef _RGT is the mentioned speed of rotation of the said 25 rotating part. 21. Apparatus according to any rhyme of the preceding claims, characterized by the fact that it additionally comprises: a detector (420) for generating a value indicative of the said speed of rotation (f _R od mentioned rotating part; where not mentioned immensified (320) has an input (360) to receive α rotation value of said speed. 22. Apparatus according to any one of claims 1 to 20, characterized in that the aforementioned user interface (102, 104, 24B) is adapted to allow a user to establish a speed of rotation value (1'bí> t) for a selectable value; wherein said intensifier (320) has an input (360) for receiving said rotation speed value. 10 23. Apparatus in accordance with any of the preceding claims, carctenzado by the fact that: the mentioned first digital signal (Sreo, Senv) may include a second signal signature (So>); and where said intensifier (320) is adapted to process 15 the aforementioned first plurality (Icomprimenh)) of input sample values so that both the first repetition frequency (fm) and the second repetition frequency dj) -) are improved in relation to said noise, even when mentioned mentioned first repetition frequency 24. Apparatus according to any precedent, characterized by the feel of: the aforementioned first digital signal (S ^ u. Sw>. $ env _{} may} include a second signature signal (S? .u) having a second repetition frequency (lra _s . and that said intensifier (320) be adapted to process the aforementioned first plurality (IcoMrtUMLMo) of input sample values, so that both the first repetition frequency (fin) and the second repetition frequency are improved in relation to noise. even when the aforementioned second repetition frequency (! /;>) is different from the aforementioned first repetition frequency, both the first repetition frequency (u _r .) and the second repetition frequency (tQ) are proportional to á. mentioned rotation speed (Írgu) of the part 5 rotatably movable (8). '25. Apparatus according to any one of the preceding claims, characterized by the fact that it further comprises: a sensor (10) for generating a measurement signal depending on said mechanical vibrations emanating from the rotation of said part 10; and means (40, 44, 94, 250, 310, 470) to generate said first digital signal (S _R} .. _b . S _M o. S _hNV ) having the mentioned sample rate (Íse) depending on the mentioned measurement signal. 26. Apparatus according to any of the claims 15 precedents, çaraçterizadq by the fact that: said sensor (l ()) is a shock pulse sensor. 27 Apparatus according to any of the preceding claims, characterized by the fact that: said input sample values of said 21) first digital signal being stored as a vector of values of. input sample, said vector having index values for assigning individual values of the input sample; the aforementioned index values ranging from a lower index value ri?;, l ^ kao) to a higher index value (i $ ^; · 1 <όμρκιμενιο · Ί; imlom * ΙγομριομΙ'.χτο Ό? 25 where the range of input sample values and indexing values are mutually selected so that the index values are values within the bottom of the input signal vector. 28. Apparatus according to any of the preceding claims, characterized by the fact that the difference (N _c ) between the two indexing values of the $ two terms in a product of the input signal (P (i, t}) is equal or greater than the determined value (Slnkk))> 29, Method to analyze the condition of a machine by reading a rotating part, with a rotation speed (f ^,}, characterized by the phallus of understanding the steps of: receive a first digital signal (Srfd. Sm _D. Senv) dependent on mechanical vibrations emanating from the rotation of the mentioned part; the mentioned first digital signal (Red)? having a sample rate (% 0; where said first digit sign (Sr ^ $ _M u. Sknv; may include noise and a first signal signature (Srsi) having a first repetition frequency and a second signal signature (S _{ > 2) having a second repetition frequency (fod comprising, additionally: processing a first plurality (leoMVRtMEnro) input sample values of said first digital signal (Sreu. Smlx Senvj in order to generate an output signal sequence (O, Sjop) having a second plurality (Oroswreraim) of sample output values (Ssrarmh where an individual input sample value (1 (1)) is attributable to a. Sample input position value (í), and an individual output sample value ((S, mup (0A θ (tl ) attributable to a sample output position value, (t) and where the processing step includes: A) generate an output sample value for an output position, of sample t, the aforementioned step of generating the output sample value, including: perform a third plurality ((u: ov.re.íMtxío) of multiplications to produce input signal products; where an input signal product is obtained by multiplying the first input sample value (1 (1)) in a first sample position (i) for a second input sample value (l.i2)), 1 (1 e- $ _5ϊ ρ _Π (ρ · t · * b) _; 1 (i - Snueto -ft + · to)) in a second sample position (12), the aforementioned second input sample value (I (iv * l · ·); l (i - tt <Oh being separated from the aforementioned first input sample value ( 1 (1)) by a number (Sjnícjo ⁴ '0 sample positions, the said number being equal or larger than * a given value (Sftoao) and adding the said third plurality (length) signal products input to produce a sum of 10 input signal products; the aforementioned sum of signal products, input being the sample output value Snupít) for the message sample position t is selected and dispensing said value of the SmdKV output sample to said sample position t; B) repeating step A) for substantially * all of the aforementioned 15 sample output position values (t) so that said signal output sequence (O * Smup) is generated, said other method comprising, additionally: execute a condition monitoring function (Fl * F2, Fn) in order to analyze the condition of the machine depending on the aforementioned output signal sequence (O * $ mdp) - 30. Method for operating an apparatus to analyze the condition of a machine having a rotating part, with a speed of rotation (ÍrotX characterized by the fact of understanding the steps of: receiving a first digital signal (S ^ ro. $ exv ₅ dependent on mechanical vibrations emanating from the rotation of said part; said first digital signal (Sr ^). having a sample rate (i'W); processing a first plurality (Icomprsmento) of input sample values of said first digital signal (Sred. Senv) in order to generate one. output signal sequence (O, having a second plurality of output sample values (S.mdpCOX where an individual input sample value (1 (h) is attributable to an input sample value position (in and a sample value, individual output ((Smo? (0)> O (t)} is attributable to an output sample position value (t); where the processing step includes 1) set the output sample position value ít) to an imeial value (tO); 2) generate an output sample value (SmdpÇ)) for the relevant sample position (t), the mentioned step of generating the output sample value including: a) set the input sample position value (í) to an initial value (g,) b) generate an input signal product (P (i, t)) by multiplying a first input sample value (I (.i)), in. a first sample position (í). by a second input sample value (U Í2 ', I (i t-S ^ ieío ~ SjNkao ⁴ ' f $ a in a second sample position (i2), the aforementioned second input sample value (Ki * Soanu ⁴ to): í (i - SmtcK) ⁴ 'Ã)) being separated from the mentioned first input sample value (I (i)) by a determined number (S ^ iao ^h 9 of sample positions; felt greater than a certain value (Sinícr '>); and ç) change the input sample value position (í) by one step ;. d) repeat step b) in order to generate another input signal product (Pti, t)) and create a summary of the generated input signal products; one e) step, d) be repeated until a third plurality repetition period ff ₈ I fj »l ' _ÍR T. _(K l, and where the value (λ _,. Λ8ΨΑη μπ of the second plurality (OcomhusonuB be established for m value large enough to allow the output signal sequence (O, to represent at least one period (T _{} R.} 5 Tor) vibration signal component (S _h ). 34. Method according to any of the claims 29 to 33. characterized by the fact of understanding the steps of: allow a user to enter data indicating a lower repetition frequency to be detected, and 0 automatically establishing the value of the second plurality (OcoMHUMENto) depends on the aforementioned indicative data of. a lower repetition frequency (fmvwJ · 35. Method according to any of the preceding claims, characterized by the fact that it comprises the steps of: 5 allow a user to enter data indicating a higher repetition frequency (¥, O _v . O, hem) to be detestable and automatically set the value 0 <_; qmpr ^ emo of the second plurality (O length) depending on the aforementioned data indicating the highest repetition frequency (Y, O _v . Ovhigh) ^to be detectable 0 36. Method according to any of the preceding claims? characterized by the fact of understanding the steps of: allowing a user to enter data indicative of a desired frequency resolution (Z) to be obtained by analyzing the output signal sequence (O, Smuf); 5 automatically establish the value of the second plurality (Ocu.MERiMENro) depending on the aforementioned data indicative of a desired frequency resolution (Z). 37. Method according to any of the preceding claims, characterized by the fact that it comprises the steps of: allowing a user to input data indicative of a desired frequency resolution (Z) to be obtained by analyzing the output signal sequence (O, Smde); set the value Oc ^ mpr return for the product of the desired frequency resolution 5 (Z.) and a constant (C, k) having a value greater than 2.0. 38. Method according to any of the preceding claims, characterized by the fact that it comprises the steps of establishing the Ocomfrimrnto value of the second plurality (O comwumemo) in the dependency 10 of data indicating a frequency resolution (Z) to be obtained by analyzing the signal output sequence (O, £ depending on data indicating a higher repetition frequency (Y, 15 (X, Ovsmou) a be detectable, and depending on data indicative of said rotation speed and depending on data indicative of said sample rate (f ^). 39. Méuxio to analyze the condition of a machine having 20 a rotating part, with a rotation speed (Got), characterized by the fact of understanding the steps of: receive a first digital time domain signal Smd. Sexv) dependent on mechanical vibrations emanating from the rotation of the mentioned part: the aforementioned first digital signal (SrkíÀ having a sample rate of 25 (Ísr): where the aforementioned first digital signal (Srhx Smd, may include noise and a first signal signature having a repeating frequency tip (ifií) comprising, adickmally: process one. first plurality PI (Icomprimemo) of input sample values of said first digital signal (Sreu. Six) in order to generate an output signal sequence ((L 8 ^. ^ 4 having a second pluranoaue P2 (O <of sample output values (^ wpV) K the aforementioned output signal sequence ((), S ^ r), being a time domain signal sequence; where said processing of said first plurality P1 of input sample values involves a third plurality P3 (tk'ortnusamto) of multiplication of input sample values to generate an output sample value (S mdp (Ü) so that the generation of the aforementioned second plurality P2 (OcoxivrimentoI of output sample values. (SmopO)) involves at least one fourth plurality P4 of multiplications (P4 ~ P2 * P3 ). 40. Method according to any of the preceding claims, characterized by the fact that it comprises the steps of: receive data indicative of an incremental value of the SmaLRIDO (L) Ratio; and means (365, 375, 375B) for generating a value of data indicative of the mentioned third plurality (CVoMPRiMEmo) depending on the mentioned incremental value of the Signal-to-Noise Ratio (Li and the mentioned data (Z, V, 1'sa, faor ) indicative of the mentioned second plural Age (OcoMpRixír.x-ro). 41 .. Method for operating an apparatus for analyzing the condition of a machine having a rotating part, with a rotation speed (Iro / L characterized by the fact of understanding the steps of receiving an analog measurement signal (Ss; .a) indicative of a vibration signal signature having a vibration frequency (Im-.λ) and a repetition frequency (fp) _; generate a digital measurement signal (Smu) dependent on the analog measurement signal, the aforementioned digital measurement signal (S _M n) having a first sample rate (fig the first sample sample being at least twice (k) the mentioned vibration frequency (Ura): generate an enveloped signal indicative of the said repetition frequency (if); generating a first digitized digital signal (Sr ^ ,. Exit, S-ume) dependent on said enveloped signal so that said first digital digitized signal has a reduced sample rate (f (.R); perform discrete time-domain autocorrelation for the first decimated digital signal (S ^ _b Stmcm Sreío.) in order to generate an intensified output signal sequence (O, S _MD p); c execute a condition monitoring function (FL F2 <Fit) in order to analyze the state of the machine depending on the mentioned intensified output signal sequence (O, $ ^ _ΓΨ ), 42, Computer program, characterized by the tact of understanding computer-readable coding means to cause a computer to perform the steps as defined in any one of claims 29 to 41 when said program is executed on a computer or on a computer apparatus. analyze, 43, Computer program product, characterized by the fact that it comprises: computer-readable media; and a computer program as defined in claim 42, said computer program being recorded on said computer-readable media.