JP2006017291A - Monitoring device and monitoring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a monitoring method capable of quickly and accurately monitoring a device that uses a rolling element, and to provide a monitoring device of lower size and cost. <P>SOLUTION: A rolling element 3 rotates stably if operation state of a bearing 5 is well, but vibration of the rolling element becomes larger by the effect of, for example, rolling of the rolling element on a rough part of a raceway surface. The abnormality such as defective operation can be detected if the amplitude value of passage vibration of the rolling element which is measured becomes larger, as it means that the rolling element rolls, for example, on the rough part of a raceway surface. Since continuing poor lubrication develops into abnormality such as wear or breakage, treatment such as refilling of lubricant in that stage prevents damage from abnormality while prevents wear or extends life. So, the state of a device which uses a rolling element can be monitored without breakup with simple configuration, and defective operation of the rolling element is detected before the occurrence of damage whose cause is defective operation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a monitoring device and a monitoring method for an axle support device for a reduction gear, an electric motor, and a railway vehicle having rolling elements used under elastic fluid lubrication, in particular, without disassembling the device. The present invention relates to a monitoring device and a monitoring method capable of detecting an abnormality.

Conventionally, various methods have been proposed as an abnormality diagnosis technique for a bearing portion of a rotating device such as a motor (Patent Documents 1 to 5). As the most general one, for example, as disclosed in Patent Document 3, an accelerometer is installed in the bearing portion, the vibration acceleration of the bearing portion is measured, and further, FFT (Fast Fourier Transform) processing is performed on this signal. Is used to extract a signal of a specific frequency component, detect shaft vibration from the value, and perform bearing diagnosis.
JP 2003-232674 A JP 2000-146762 A JP 2002-22617 A JP 2003-202276 A JP 2001-33469 A

  Here, in the abnormality diagnosis technique disclosed in Patent Document 3, the presence / absence and position of a scratch, which is a periodic phenomenon, is specified by calculation based on the dimensions of the bearing and the condition of the rotational speed, but is not periodic. There has been a problem that a new device is required to diagnose a failure in the operation state, which is a phenomenon (for example, poor lubrication, preload application, bearing mounting failure, etc.).

  Furthermore, the technique disclosed in Patent Document 4 will be described. FIG. 6 is a diagram corresponding to FIG. According to Patent Document 4, by measuring the vibration of the rolling bearing, the specific frequency component shown in FIG. 6 is obtained, and based on this, it can be specified whether an abnormality has occurred in the inner ring, the outer ring, the rolling element, or the cage. . More specifically, Sb in FIG. 6 is a frequency component based on the rotation of the rolling element, and Sc is a frequency component based on the rotation of the cage. Therefore, if Sb is large, it can be determined that an abnormality has occurred in the rolling element, and if Sc is large, it can be determined that an abnormality has occurred in the cage. However, for abnormality diagnosis, a plurality of vibration components must be analyzed, and the processing becomes complicated.

  On the other hand, according to the technique disclosed in Patent Document 5, a rolling element in a rolling bearing under elastohydrodynamic lubrication performs a combined motion of a rolling motion and a sliding motion during the operation of the rolling bearing. Is defined as the revolution slip ratio, and when the slip ratio increases, it is determined that an abnormality has occurred in the rolling bearing. However, in order to obtain this slip ratio, the cage must be a non-magnetic material, and there is a problem that accurate measurement is not always possible depending on the magnitude of the magnetic field in the environment.

  In view of the problems in the conventional technology, the present invention is capable of monitoring a device using a rolling element quickly and accurately based on a new idea different from the conventional one, and further, downsizing and cost reduction are possible. An object is to provide a monitoring device.

The monitoring device of the first aspect of the present invention comprises:
In a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
A sensor for detecting at least the passing vibration of the rolling element;
Extraction means for extracting the amplitude value based on the passing vibration of the rolling element detected by the sensor;
And determining means for determining that an abnormality has occurred in the rotating device based on the amplitude value of the passing vibration of the rolling element extracted by the extracting means and a reference value.

The monitoring device of the second present invention comprises:
In a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
A sensor for detecting at least the passing vibration of the rolling element;
Based on the passing vibration of the rolling element detected by the sensor, extracting means for extracting the periodic variation;
And determining means for determining that an abnormality has occurred in the rotating device based on the period fluctuation of the rolling element extracted by the extracting means and a reference period.

The monitoring device of the third present invention comprises:
In a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
A sensor for detecting at least the passing vibration of the rolling element;
Based on the passing vibration of the rolling element detected by the sensor, extracting means for extracting the periodic variation;
Detecting means for detecting the rotational speed of the rotating body;
The ratio of the revolution speed of the rolling element extracted by the extraction means and the rotation speed of the rotating body detected by the detection means is compared with a predetermined value to determine that an abnormality has occurred in the rotating device. And determining means.

The monitoring method of the fourth aspect of the present invention is:
In a monitoring method for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
Detecting at least a passing vibration of the rolling element;
Extracting the amplitude value based on the detected passing vibration of the rolling element;
And determining that an abnormality has occurred in the rotating device based on the extracted amplitude value of the passing vibration of the rolling element and a reference value.

The monitoring method of the fifth aspect of the present invention is:
In a monitoring method for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
Detecting at least a passing vibration of the rolling element;
Extracting the periodic variation based on the detected passing vibration of the rolling element;
And determining that an abnormality has occurred in the rotating device based on the extracted periodic fluctuation of the rolling element and a reference period.

The monitoring method of the sixth aspect of the present invention is:
In a monitoring method for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
Detecting at least a passing vibration of the rolling element;
Extracting the periodic variation based on the passing vibration of the rolling element;
Detecting the rotational speed of the rotating body;
And comparing the ratio of the revolution speed of the rolling element and the rotation speed of the rotating body with a predetermined value to determine that an abnormality has occurred in the rotating device.

  According to the monitoring device of the first aspect of the present invention, in the monitoring device for monitoring a rotating device having a rotating body supported by using a rolling element to be lubricated, at least a sensor for detecting a passing vibration of the rolling element, Based on the passing vibration of the rolling element detected by the sensor, the extracting means for extracting the amplitude value, the amplitude value of the passing vibration of the rolling element extracted by the extracting means, and the reference value, the rotation Since the apparatus has a determination means for determining that an abnormality has occurred in the apparatus, the abnormality determination can be easily and reliably performed only by monitoring the amplitude value of the passing vibration of the rolling element.

Here, the passing vibration of the rolling element means that the load sharing changes depending on the position of each rolling element in the load region, and the displacement amount and the direction of the displacement of the member (for example, the rotating shaft) on which the rolling element rolls are minute. And the passing frequency (fc) of the rolling element is expressed by the following equation.
fc = (fr / 2) (1− (Da / dm) · cos α) [Hz] (1)
Here, fr: inner ring rotational speed (Hz), Da: rolling element diameter (mm), dm: pitch circle diameter (mm), α: contact angle.

  If the operating condition of the device using the rolling element is good, the rolling element also rotates stably. For example, the rolling element vibrates greatly due to the rolling element rolling on a rough part of the raceway surface. Become. Therefore, if the amplitude value of the passing vibration of the rolling element being measured is large, for example, it means that the rolling element has rolled on a rough part of the raceway surface, and therefore it is possible to detect an abnormality in the operating condition. Become. If the state of poor lubrication continues, it will develop into a major abnormality such as wear or breakage. At this stage, replenishment of lubricant etc. can prevent damage such as abnormality and prevent wear. And prolongs the service life. According to the present invention, it is possible to monitor the state of a device using a rolling element with a simple configuration without disassembling, and to detect that the operating state of the rolling element is bad before damage based on the bad operating state occurs. It will be possible. The “apparatus using rolling elements” includes a rolling bearing, a ball screw mechanism, a linear guide, and the like.

  The reference value is an amplitude value extracted based on the passing vibration of the rolling element detected by the sensor when the rotating device is operating normally. It is preferable to determine that an abnormality has occurred in the rotating device when the difference between the amplitude value of the passing vibration of the moving body and the reference value exceeds a predetermined value.

  The reference value is an amplitude value extracted based on the passing vibration of the rolling element detected by the sensor when the rotating device is operating normally. It is preferable to determine that an abnormality has occurred in the rotating device when the ratio between the amplitude value of the passing vibration of the moving body and the reference value exceeds a predetermined value.

  According to a second aspect of the present invention, there is provided a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated, wherein at least a sensor for detecting a passing vibration of the rolling element; Based on the detected passing vibration of the rolling element, an extracting means for extracting the periodic fluctuation, the periodic fluctuation of the rolling element extracted by the extracting means, and a reference period, an abnormality occurs in the rotating device. Therefore, it is possible to easily and reliably make an abnormality determination only by monitoring the periodic fluctuation of the passing vibration of the rolling element.

  If the operating condition of the device using the rolling element is good, the rolling element also rotates stably. However, if the operating condition is poor, the rolling element rotation is unstable due to partial sliding friction. become. Therefore, if the period of the passing vibration of the rolling element being measured is large, for example, it means that the rolling element has come to slide on the raceway surface, and thus it is possible to detect an abnormality in the operating condition.

  The reference period is a period that is extracted based on the passing vibration of the rolling element detected by the sensor when the rotating device is operating normally, and the determination means includes the rolling element. It is preferable to determine that an abnormality has occurred in the rotating device when the difference between the periodic fluctuation of the passing vibration and the reference period exceeds a predetermined value.

  According to a third aspect of the present invention, there is provided a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated, wherein at least a sensor for detecting a passing vibration of the rolling element; Based on the detected passing vibration of the rolling element, extraction means for extracting the periodic fluctuation, detection means for detecting the rotational speed of the rotating body, revolution speed of the rolling element extracted by the extracting means, Since it has judgment means for judging that an abnormality has occurred in the rotating device by comparing the ratio of the rotational speed of the rotating body detected by the detecting means with a predetermined value, it is easy to judge abnormality of the rotating device This can be done reliably and reliably.

  For example, when the rotating device is a bearing and the rotating body is a rotating body in which the outer ring is fixed and the inner ring rotates, the periodic fluctuation of the rolling element corresponds to the rotational speed of the cage during normal operation. The rotational speed of the cage is determined by fc = (fr / 2) (1− (Da / dm) · cos α). Here, when the cycle variation of the rolling element changes despite the constant speed of the inner ring, the raceway surface is roughened and the slip rate is changed. It can be done easily and reliably.

  The sensor preferably includes an acceleration sensor.

  The sensor preferably includes a strain gauge.

  According to a fourth aspect of the present invention, there is provided a monitoring method for monitoring a rotating device having a rotating body supported by using a rolling element to be lubricated, wherein at least a step of detecting a passing vibration of the rolling element is detected. Based on the step of extracting the amplitude value based on the passing vibration of the rolling element, the amplitude value of the passing vibration of the rolling element extracted, and the reference value, it is determined that an abnormality has occurred in the rotating device. Therefore, the abnormality determination of the rotating device can be performed easily and reliably.

  The reference value is an amplitude value extracted based on the detected passing vibration of the rolling element when the rotating device is operating normally, and the amplitude value of the passing vibration of the rolling element. When the difference from the reference value exceeds a predetermined value, it is preferable to determine that an abnormality has occurred in the rotating device.

  The reference value is an amplitude value extracted based on the detected passing vibration of the rolling element when the rotating device is operating normally, and the amplitude value of the passing vibration of the rolling element. When the ratio with the reference value exceeds a predetermined value, it is preferable to determine that an abnormality has occurred in the rotating device.

  According to a fifth monitoring method of the present invention, there is provided a monitoring method for monitoring a rotating device having a rotating body supported by using a rolling element to be lubricated. Extracting the periodic fluctuation based on the passing vibration of the rolling element; determining determining that an abnormality has occurred in the rotating device based on the extracted periodic fluctuation of the rolling element and a reference period; Therefore, the abnormality determination of the rotating device can be easily and reliably performed.

  The reference period is a period that is extracted based on the detected passing vibration of the rolling element when the rotating device is operating normally, and the determination means passes the rolling element. It is preferable to determine that an abnormality has occurred in the rotating device when the difference between the vibration fluctuation and the reference period exceeds a predetermined value.

  According to a sixth monitoring method of the present invention, there is provided a monitoring method for monitoring a rotating device having a rotating body supported by using a rolling element to be lubricated, the step of detecting at least passing vibrations of the rolling element, and the rolling element. The ratio of the step of extracting the periodic fluctuation based on the passing vibration, the step of detecting the rotational speed of the rotating body, the revolution speed of the rolling body and the rotational speed of the rotating body is a predetermined value. By comparing, it has a step of determining that an abnormality has occurred in the rotating device, so that the abnormality determination of the rotating device can be easily and reliably performed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a monitoring device according to the first embodiment. In FIG. 1, a monitoring device 10 detects an abnormality using a bearing 5 formed of an inner ring 1, an outer ring 2, a ball 3 rolling between both wheels and a cage 4 as a rotating device. Here, the outer ring 2 is fixed, the inner ring 1 is fitted to a rotating shaft (not shown) and is a rotating body, and the ball 3 constitutes a rolling element.

  In FIG. 1, an acceleration sensor 11 for detecting rolling element passing vibration is fixed to an outer ring 2 which is a fixed wheel. The sensor 11 is fixed by bolt fixing, bonding, bolt fixing and bonding, or embedding by a molding material, A method with an anti-rotation function can be applied when fixing bolts. When the sensor 11 is molded in this way, it is possible to prevent moisture from entering, and further to improve the anti-vibration property against external vibration, so that the reliability of the sensor itself can be greatly improved.

  In addition, although the acceleration sensor was shown here as a sensor which detects rolling-element passage vibration, it is AE (Acoustic Emission) sensor, an ultrasonic sensor, a shock pulse sensor, etc., or speed, strain, stress, displacement type. Any sensor may be used as long as vibration can be converted into an electrical signal, and when it is attached to a machine with a lot of noise, it is preferable to use an insulating type because it is less affected by noise. Moreover, you may obtain | require the rolling element passage period using the change of the distortion at the time of rolling element passage. Further, a vibration detecting element such as a piezoelectric element may be molded into plastic or the like to form a rolling element passing vibration detecting sensor.

  The signal output from the sensor 11 is input to a signal processor 12 as extraction means. After the amplitude value or period of the passing vibration of the rolling element is extracted here, it is input to the control device 13 as determination means. The When it is determined that the bearing is abnormal based on the amplitude value or cycle of the passing vibration of the rolling element, the control device 13 transmits an alarm signal to the output device (monitor, alarm device, etc.) 14 to display an indication of the abnormality of the bearing 5 or the like. To alert the user. The signal processor 12 and the control device 13 are integrated and referred to as a controller 15.

Next, a specific operation of the monitoring device 10 will be described. First, the control device 13 stores the amplitude value or cycle of the passing vibration of the rolling element in the initial state as a reference value. FIG. 2A is a graph showing a signal output from the sensor 11 in a normal state, and FIG. 2B is a graph showing a signal output from the sensor 11 in an abnormal state. Under normal conditions, the rolling element passing vibration component _{A 0} appears as a peak around 110 Hz.

  Here, when an abnormal moment load is applied to the bearing 5, for example, the preload and the clearance are affected, and the operation state of the bearing becomes poor. Further, when the lubrication state is poor, the sliding friction is partially increased, so that the rotation of the rolling element becomes unstable and the amplitude fluctuation of the rolling element passing vibration becomes large (the amplitude value greatly fluctuates).

More specifically, when the rolling element slip increases with respect to the rolling element passing vibration component A ₀ in the normal state, the period of the passing vibration of the rolling element is delayed, so that the rolling element passage in the abnormal state is delayed. peak vibration components a ₁ becomes deviates to the left. Further, when or have rough raceways for the rolling element passing vibration component A ₀ in the normal state, the peak of the rolling element passing vibration component A ₁ in the abnormal condition is the increase.

Using this, the control device 13 determines the ratio (| A ₀ ) of the difference between the amplitude (reference value) A ₀ of the rolling element passing vibration in the stable period (during normal operation) and the current amplitude A ₁ of the rolling element passing vibration. -A ₁ | / _{a 0)} of seeking, if the value exceeds the set value _{(0.1) (| a 0 -A} 1 | a / a 0> 0.1), the bearing 5 is poor lubrication It can be determined that it is in a state, and an alarm signal can be transmitted by the output device 14.

  In the present embodiment, the set value is set to 0.1, but this value can be arbitrarily set and changed (preferably 0.1 to 0.3) according to the operating state and application.

As another example, the control device 13 determines the ratio (A ₁ / A ₀ ) between the amplitude A ₀ of the rolling element passing vibration during the stable period (during normal operation) and the current amplitude A ₁ of the rolling element passing vibration. ) is the case of out-of-tolerance _{(0.9~1.1) (a 1 / a} 0 <0.9,1.1 <a 1 / a 0), and the operating condition of the bearing 5 is bad It can be determined and an alarm signal can be transmitted to the output device 14. In this embodiment, the allowable range is (0.9 to 1.1), but this range is arbitrarily set / changed (preferably (0.7 to 1.3) depending on the operating state and application. Any range) is possible.

  In addition, when paying attention to the generation cycle of rolling element passing vibration, it is possible to cope with the same method as described above by determining the set value or the allowable range according to the operating state of the rotating device and the application.

  Further, the control device 13 extracts the periodic fluctuation based on the passing vibration of the rolling element, determines the rotational speed of the cage 4 from the rotational speed difference between the inner and outer rings, and compares the ratio with a predetermined value. It can also be determined that an abnormality has occurred in the bearing 5.

  In this case, the comparison was made using the instantaneous value (peak value) of the amplitude and period as the amplitude and generation period of the rolling element passing vibration, but the average value such as the mean square value within the predetermined time, overall, etc. The calculated value of may be used.

  In addition, by providing storage devices that store parts that show abnormal values and their order in the control device, etc., it is possible to easily identify abnormal parts and quickly perform repairs, replacements, etc. It becomes.

  Depending on the rotating device or the like, a poorly lubricated state may appear locally during operation, and recovery may occur after a short period of time. For this reason, operation is performed at the moment when the control device 13 determines that lubrication is defective. If it is stopped or an alarm is issued, an emergency stop or the like of the rotating device may be performed more than necessary. Therefore, the rotating device can be stopped or an alarm can be issued only when a state of poor lubrication is detected continuously for a predetermined time (several seconds).

  The control device 13 can be unitized if a microcomputer or the like is used, and it is even better because it can be downsized and modularized. The place where the signal processor 12, the control device 13, and the output device 14 are installed may be built in the bearing device, or may be installed as a monitoring system in the mechanical equipment. In such a case, one monitoring device may be provided, but a plurality of monitoring devices may be provided corresponding to the bearings.

  Hereinafter, a monitoring system including a monitoring device will be described in detail with reference to the drawings. FIG. 3 is a schematic configuration diagram of such a machine facility monitoring system. This mechanical equipment monitoring system 100 detects an abnormality caused by wear or breakage of each component of the rolling bearing 5 with respect to the rolling bearing 5 that supports the axle of the railway vehicle.

  In the present embodiment, the bearing 5 is a sensor-equipped bearing in which a sensor 11 that detects passage vibration of the bearing and outputs it as an electrical signal is assembled to an outer ring that is a component of the bearing. A plurality of sensor-equipped bearings 5 are used in one vehicle.

  The machine facility monitoring system 100 of this embodiment analyzes a plurality of sensors 11 as detectors installed for each bearing 5 and the output of each sensor 11 by a predetermined arithmetic process, and prepares the analysis results in advance. A signal processing unit 20 serving as an extraction unit and a determination unit that determines whether or not there is an abnormality in the bearing 5 in comparison with a reference value, and the analysis results and determination results of the signal processing unit 20 are displayed in a predetermined display form. Or a control processing unit 30 that feeds back a control signal corresponding to the determination result to the control system of the railway vehicle.

  Similar to the above-described embodiment, the sensor 11 detects the passing vibration of the rolling element as a physical quantity that changes in accordance with the rotation state of the bearing 5, converts it into an electrical signal, and transmits it to the signal processing unit 20.

  The signal processing unit 20 is, for example, a one-chip microcomputer or a one-board microcomputer developed exclusively, and temporarily detects detection data transmitted from each sensor 11 via the microcomputer 16 as shown in FIG. The data collection / distribution function unit 21 that accumulates and distributes the accumulated data to the analysis units 23 and 24 equipped according to the type of the data, the specifications of the bearing 5 (number of rolling elements, etc.) and the bearing 5 By comparing the internal memory 26 in which various physical quantities such as vibration during normal operation are stored as reference values, and the analysis results in the analysis units 23 and 24 with reference values stored in the internal memory 26, A comparison / determination function unit 25 which is a determination unit for determining the presence / absence of an abnormality and specifying an abnormal part, and the analysis results and comparison / determination function unit 25 in each analysis unit 23 and 24 And it outputs the determination result to the control processor 30 that.

  In the case of this embodiment, the analysis unit 23 is for analyzing vibration information, and obtains a frequency spectrum included in the vibration. The analysis unit 24 obtains the rotation speed of the bearing for analyzing the rotation speed information. Each analysis unit 23 and 24 performs a prescribed analysis process including cutting unnecessary parts (noise) and clarifying necessary parts so that the input information can be compared with a reference value.

  More specifically, in the case of vibration information detected by the sensor 11, noise component removal or a specific frequency component is performed by the filter processing function unit 22 provided between the data collection / distribution function unit 21 and the analysis unit 23. The vibration signal after filtering is input to the analysis unit 23.

  The analysis unit 23 performs specified analysis processing such as absolute value processing, envelope processing, and frequency analysis on the input vibration signal, so that the input vibration data can be compared with a reference value in a frequency region. Convert to data.

  The comparison / determination function unit 25 compares the vibration frequency data obtained from the analysis result of the analysis unit 23 with the reference value stored in the internal memory 26, and determines whether or not the bearing 5 is abnormal as described above. To do.

  The comparison / determination function unit 25 refers to various data such as the rotational speed obtained from the other analysis units 24 and the specification specifications stored in the internal memory 26 when performing the determination by comparing the frequency components. , For accuracy of judgment.

  The specific processing in the analysis units 23 and 24 and the comparison / determination function unit 25 is not described in detail, but is not limited to the above-described method. Various known methods or the applicant of the present application previously proposed. A plurality of methods such as various determination methods (Japanese Patent Application Laid-Open Nos. 2003-130763, 2003-202276, 2003-130724, etc.) can be used.

  The control processing unit 30 controls the operation of the result output unit 31 as display means for displaying the analysis result and determination result of the signal processing unit 20 in a predetermined display form, and the drive mechanism of the vehicle in which the bearing 5 is incorporated. The control system includes a controller 32 that feeds back a control signal corresponding to the determination result of the comparison determination function unit 25.

  Specifically, the result output unit 31 notifies the analysis result or determination result of the signal processing unit 20 by displaying an image on a monitor or printing output to a printer, and the determination result of the signal processing unit 20 is abnormal. In this case, notification is performed by blinking a warning light or operating an alarm. The determination result may be stored in a storage medium such as a memory or HDD, or may be displayed in real time via the result output unit 31.

  For example, when the determination result of the signal processing unit 20 is abnormal, the controller 32 sends a control signal indicating stop or deceleration of the vehicle to the vehicle controller according to the degree of abnormality.

  In the monitoring system for mechanical equipment according to the present embodiment described above, the output of the sensor 11 incorporated in the rolling bearing 5 is analyzed by the signal processing unit 20, and the analysis result is prepared in advance as a reference value. By comparing, it is possible to determine whether there is an abnormality in the rolling bearing 5, so that the rolling bearing 5 itself or the railcar itself including the rolling bearing 5 can be determined in a normal use state without being disassembled. is there.

  Therefore, it is possible to reduce maintenance and management costs by reducing the frequency of laborious disassembly / assembly work. In addition, since the judgment is mechanically performed by analysis and comparison by the prescribed arithmetic processing, there is no possibility that the judgment varies depending on the skill level of the person in charge of inspection and individual differences compared with the conventional visual inspection, and diagnosis of the presence or absence of abnormality is possible. Reliability can be improved.

  In addition, since the signal processing unit 20 itself can be a small dedicated unit of one chip or one board, the entire system is significantly more compact than a conventional monitoring system that uses a general-purpose personal computer as an information processing device. Since only a small space is required for the equipment, the equipment to the mechanical equipment including the bearings (that is, the railway vehicle etc.) can be easily equipped.

  FIG. 4 is a schematic configuration diagram showing a lubricant supply device using the monitoring device according to the present embodiment. As shown in FIG. 4, the bearing 5 includes an outer ring 2, an inner ring 1, a plurality of rollers 3 that are rolling members disposed between both wheels 1 and 2, and a cage that holds the rollers 3. It consists of four.

  The outer diameter side of the bearing 5 is connected to the pump P through the supply pipe 6. The grease pushed out from the pump P is inserted into the bearing portion 5 through the supply pipe 6 and adheres to the contact surface of the outer ring 2 of the bearing portion 5, the raceway surface 3 of the inner ring 1 and the contact surface of the outer ring 2 and the cage 4. Therefore, proper lubrication is performed. A sensor 11 for measuring the passing vibration of the rolling element is disposed on the outer ring 2.

  The lubricant replenishing device that replenishes the bearing 5 with a lubricant (here, grease) includes a grease tank 7 in which the grease is stored, a pump P that feeds the grease from the grease tank 7 to the bearing 5 through the supply pipe 6, and a pump A motor M that drives P, a sensor 11 that measures the rolling element vibration of the bearing 5, and a control that also serves as an extraction unit and a determination unit that receive signals output from the sensor 11 and determine whether there is an abnormality in the bearing 5 Part 8.

  An appropriate amount of grease is stored in advance in the grease tank 7. The grease stored in the grease tank 7 is guided to the supply pipe 6 by driving the pump P. One of the supply pipes 6 is connected to the grease tank 7 and the other is connected to the bearing 5 via the pump P. In the present embodiment, the pump P is configured to be driven by the rotation of the motor M. The bearing 5 may have a discharge pipe (not shown) for discharging the grease from the internal space.

  The bearing 5 is configured such that grease is supplied to the internal space from the supply pipe 6. Here, the grease supplied from the supply pipe 6 is supplied to the internal space of the bearing 5 through a grease supply hole provided in the outer ring 2.

  The operation of the lubricant supply device according to the present embodiment will be described. After starting the operation of the bearing 5, the control unit 8 grasps the initial state of vibration based on the signal output from the sensor 11. When the operation is further continued, based on the signal output from the sensor 11, the control unit 8 determines whether or not an abnormality has occurred in the bearing 5, for example, surface roughness is occurring on the raceway surface. If it is determined, the motor M is driven and controlled, the pump P is operated, and grease is supplied via the supply pipe 6. As a result, the life of the bearing 5 can be kept long.

  FIG. 5 is a cross-sectional view of a hub unit (rotating device) that supports the wheel with respect to the suspension device, to which the sensor 11 is assembled. A wheel constituting the wheel and a disc rotor constituting the braking device are fixed to a flange 110 formed on the outer peripheral surface of the outer end portion of the hub 114 formed in a hollow cylindrical shape by a plurality of studs (not shown). An outer ring raceway 101a is formed on the outer peripheral surface of the intermediate portion of the hub 114, and the inner ring 101 having the inner ring raceway 101a on the outer peripheral surface is externally fitted and fixed to a stepped portion 116 formed on the inner end portion. Thus, the rotating wheel 113 is configured. A spline shaft attached to a constant velocity joint (not shown) is inserted into a spline hole 117 formed at the center of the hub 114 constituting such a rotating wheel 113 in an assembled state to the automobile.

  On the other hand, around the rotating wheel 113, a double row outer ring raceway 102a, 102a is arranged on the inner peripheral surface, a mounting portion 102b is formed on the outer peripheral surface, and the outer ring 102 which is a stationary wheel formed concentrically with the rotating wheel 113. is doing. Of these, the attachment portion 102b is used for supporting and fixing the outer ring 102 to a suspension device (not shown) such as a knuckle. Also, between each outer ring raceway 102a, 102a and each inner ring raceway 101a, 101a, a plurality of balls 103, 103, each of which is a rolling element, are provided, and on the inner diameter side of the outer ring 102 fixed to the suspension device, The rotating wheel 113 that fixes the wheel including the wheel can be rotatably supported. In the case of a rolling bearing unit for automobiles that is heavy, tapered rollers may be used as the rolling elements in place of the balls 103 and 103 as shown. Further, instead of directly forming the outer ring raceway 101a on the outer peripheral surface of the hub 114, it may be formed on the outer peripheral surface of a separate inner ring.

  Further, seal rings 111 and 111 are mounted between the inner peripheral surface of both ends of the outer ring 102, the outer peripheral surface of the intermediate portion of the hub 114, and the outer peripheral surface of the inner end of the inner ring 101, respectively. The opening portions at both ends of the space 112 provided with are closed. The grease sealed in the space 112 is prevented from leaking to the outside, and foreign matters floating outside are prevented from entering the space 112.

  On the other hand, the mounting hole 102c is formed in the boss 102d at the axially intermediate portion of the outer ring 102 so as to penetrate from the outer peripheral surface of the outer ring 102 to the inner peripheral surface. A sensor unit 118 including the sensor 11 is attached to the attachment hole 102c. The sensor unit 118 includes the sensor 11 that detects vibration and the rotation speed sensor 119 as in the above-described embodiment. The output signal of the sensor 11 is input to a signal processor 12 as extraction means, and after the amplitude value or period of the passing vibration of the rolling element of the hub unit 105 is extracted here, it is sent to the control device 13 as determination means. Entered. When it is determined that the bearing is abnormal based on the amplitude value or cycle of the passing vibration of the rolling element, the control device 13 transmits an alarm signal to the output device (monitor, alarm device, etc.), and a display indicating the abnormality of the hub unit 105. To attract the attention of drivers and users.

  The threshold TH is set based on the theoretical speed ratio fct / fr using the measured value of the rolling element passing vibration obtained from the signal of the sensor 11 and the signal of the rotational speed sensor 119, and the actually measured speed ratio fc / fr is set to the threshold TH. In comparison, if it exceeds that, it can be determined that there is an abnormality (see FIG. 7). Note that fct is a theoretical cage rotation speed (equal to rolling element passing vibration), fr is an inner ring rotation speed, and fc is an actually measured cage rotation speed. These are obtained by the above-described equation (1) (see FIG. 6).

  FIG. 8 is a cross-sectional view of a hub unit according to a modification. The embodiment shown in FIG. 8 is different from the embodiment shown in FIG. 5 in that a sensor unit 118 ′ includes an acceleration detection sensor 11 a in addition to the sensor 11 and the rotation speed sensor 119. The acceleration detection sensor 11a has a function as an ABS sensor for automobiles or a CTS sensor for railway vehicles, and in conjunction with the sensor 11 for measuring rolling element passing vibration and the rotation speed sensor 119, the speed of the vehicle. The accuracy of control and abnormality detection can be improved. In this case, the sensor 11 for measuring the rolling element passing vibration and the sensor 11a for detecting the acceleration road can be integrated sensors capable of measuring two directions. Further, by devising the signal processing, one acceleration detection sensor in the traveling direction can be used as the abnormality detection sensor together with the speed control sensor.

  By the way, in the above-mentioned embodiment, an acceleration sensor is attached in the vicinity of the bearing to detect abnormal vibration of the bearing and perform bearing diagnosis. However, in the abnormality diagnosis by the acceleration sensor, in order to mainly detect periodic vibration due to scratches caused by peeling of the bearing raceway surface, the occurrence of oil film breakage caused by poor lubrication or the occurrence of wear due to revolution slip is detected at an early stage. For this purpose, further ingenuity is required. Therefore, in the following embodiment, in addition to the abnormality diagnosis method using a vibration sensor, a highly accurate abnormality diagnosis is made possible by measuring the revolution speed of the rolling element using a strain gauge.

  FIG. 9 is a schematic configuration diagram of a monitoring device according to the second embodiment. In FIG. 9, the monitoring device 210 includes an inner ring 201 fixed to the rotation shaft S, an outer ring 202 fixed to the housing H, a ball (rolling element) 203 that rolls between both wheels, and a holder 204. The rolling bearing 205 is used as a rotating device to detect the abnormality.

  In FIG. 9, a notch 202a is formed on the outer peripheral surface of the outer ring 202, and a strain gauge 211 is attached thereto with an adhesive or the like. The strain gauge 211 as a sensor outputs an electrical signal corresponding to the resistance change of the internal conductor when it is deformed according to the strain generated in the outer ring 202, and therefore, a bridge box for taking out the electrical signal. 212.

  The electrical signal output from the bridge box 212 is amplified by the strain amplifier 213 and the DC amplifier 214 and converted into a DC voltage. Further, the noise is processed by passing through the filter 215, and then compared with the reference voltage by the comparator 216. Thus, the passing strain of the outer ring 202 when passing the ball 203 is extracted, and the cage rotating speed (that is, rolling element passing vibration) fc can be obtained by counting the passing strain per unit time. The determined holder rotation speed is transmitted from the determiner 217 to the digital processing unit 218.

  On the other hand, a vibration sensor 241 is attached to the outer peripheral surface of the housing H outside the outer ring 202 in the radial direction. A signal output from the vibration sensor 241 is amplified by an amplifier 242, passes through a filter 243, is subjected to noise processing, and is subjected to A / D conversion by an A / D converter 244. The obtained vibration V is transmitted from the A / D converter 244 to the digital processing unit 218.

  On the other hand, a rotation speed signal (that is, an inner ring rotation speed) SP of the rotation shaft S is transmitted from the rolling bearing control unit 240 to the digital processing unit 218.

  According to the present embodiment, referring to FIG. 7, the measured value (fc) of rolling element passing vibration obtained from the signal of strain gauge 211 and the rotational speed of rotating shaft S output from control unit 240 of the rolling bearing. The signal (SP = fr) is used to compare with a predetermined threshold value, and when it exceeds the threshold value, it can be determined that there is an abnormality. In this embodiment, the vibration sensor 241 is used to simultaneously detect the vibration of the rolling bearing 205 and perform backup, and an inappropriate signal is output when the strain gauge 211 is disconnected. In such a case, the measured value (fc) of the rolling element passing vibration can be obtained using the signal from the vibration sensor 241.

  FIG. 10 is a perspective view showing an example of a notch formed on the outer peripheral surface of the outer ring of the rolling bearing. A notch 202 a shown in FIG. 10A is formed over the entire width in the axial direction of the outer ring 202, and the bottom surface of the notch 202 a is a cylindrical surface centered on the axis of the outer ring 202. A notch 202 a ′ shown in FIG. 10B is formed only at the center in the axial direction of the outer ring 202, and the bottom surface of the notch 202 a ′ is a cylindrical surface centered on the axis of the outer ring 202. A notch 202a ″ shown in FIG. 10C is formed over the entire axial width of the outer ring 202, and the bottom surface of the notch 202a ″ is a flat surface. The notch 202a ′ ″ shown in FIG. 10D is formed only at the center in the axial direction of the outer ring 202, and the bottom surface of the notch 202a ′ ″ is a flat surface.

  FIG. 11 is a cross-sectional view in the direction orthogonal to the axis of the rolling bearing showing an example of wiring from the strain gauge. In the example shown in FIG. 11A, the lead wire W of the strain gauge 211 affixed to the notch 202a is taken out to the outer peripheral surface via a radial through hole Ha formed in the housing H, and is not shown. Connected to the bridge circuit. In the example shown in FIG. 11B, the lead wire W of the strain gauge 211 attached to the notch 202a is taken out to the end surface side in the axial direction of the outer ring 202 and connected to a bridge circuit (not shown). Accordingly, the notch 202a is preferably the type shown in FIG. 10A or FIG. 10C, but a groove for routing the lead wire W may be formed on the outer ring outer periphery. In the example shown in FIG. 11C, the lead wire W of the strain gauge 211 attached to the notch 202a is taken out to the outer peripheral surface through a tangential through hole Ha formed in the housing H, and is not shown. Connected to the bridge circuit.

  FIG. 12 is a diagram illustrating a configuration example of a bridge circuit using a strain gauge. In the case of the example shown in FIG. 12A, a bridge circuit is assembled by a two-wire one-active gauge method using one strain gauge. In the case of the example shown in FIG. 12B, a single strain gauge is used. However, in order to eliminate the temperature effect of the lead wire, a bridge circuit is assembled by the 3-wire type 1 active gauge method. Stable output can be obtained. In the case of the example shown in FIG. 12 (c), a bridge circuit is constructed by a two-wire two-active gauge method using two strain gauges, thereby obtaining a double output. In the case of the example shown in FIG. 12D, since a bridge circuit is constructed by using a two-wire two-sided active gauge method using two strain gauges, twice the output can be obtained and temperature compensation can be performed. . In addition, it is preferable to affix the strain gauge so that the gauge part G (see FIG. 10) is positioned on the rolling surface of the rolling element.

  The present invention has been described above with reference to the embodiments. However, the present invention is not limited to the above-described embodiments, and can of course be changed or improved within the scope of the invention.

It is a schematic block diagram of the monitoring apparatus concerning 1st Embodiment. FIG. 2A is a graph showing a signal output from the sensor 11 in a normal state, and FIG. 2B is a graph showing a signal output from the sensor 11 in an abnormal state. It is a schematic block diagram of the monitoring system containing a monitoring apparatus. It is a schematic block diagram which shows the lubricant supply apparatus using the monitoring apparatus. It is sectional drawing of the hub unit which assembles | attaches the sensor 11 and supports a wheel with respect to a suspension apparatus. It is a figure for demonstrating a prior art example. It is a graph which shows speed ratio on the vertical axis and time on the horizontal axis. It is sectional drawing of the hub unit concerning a modification. It is a schematic block diagram of the monitoring apparatus concerning 2nd Embodiment. It is a perspective view which shows the example of the notch formed in the outer peripheral surface of the outer ring | wheel of a rolling bearing. It is a sectional view in the direction perpendicular to the axis of a rolling bearing showing an example of wiring from a strain gauge. It is a figure which shows the structural example of the bridge circuit using a strain gauge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner ring 2 Outer ring 3 Ball 4 Cage 5 Bearing 6 Supply pipe 7 Grease tank 8 Control unit 10 Monitoring device 11 Sensor 11a Sensor for acceleration detection 12 Signal processor 13 Control device 14 Output device 20 Signal processing unit 21 Distribution function unit 22 Filter processing function unit 23 Analysis unit 23 Each analysis unit 24 Analysis unit 25 Comparison determination function unit 26 Internal memory 30 Control processing unit 31 Result output unit 32 Controller 100 Monitoring system 101 Inner ring 101a Inner ring track 102 Outer ring 102a Outer ring track 102b Attachment unit 102c Mounting hole 103 Ball 110 Flange 111 Seal ring 112 Space 113 Rotating wheel 114 Hub 116 Step portion 117 Spline hole 118 Sensor unit 119 Rotational speed sensor 201 Inner ring 202 Outer ring 202a Notch 203 Ball 204 Cage 205 Bearing 210 Monitoring Device 211 Gauge 212 Bridge box 213 DC strain amplifier 214 Amplifier 215 Filter 216 Comparator 218 Digital processing unit 221 Vibration sensor 222 Amplifier 223 Filter 224 Converter 240 Control unit G Gauge unit H Housing Ha Radial through hole Ha Tangential through hole S Rotation Shaft V Vibration W Lead wire M Motor P Pump

Claims (14)

In a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
A sensor for detecting at least the passing vibration of the rolling element;
Extraction means for extracting the amplitude value based on the passing vibration of the rolling element detected by the sensor;
A monitoring device comprising: a determination unit that determines that an abnormality has occurred in the rotating device based on an amplitude value of a passing vibration of the rolling element extracted by the extraction unit and a reference value.   The reference value is an amplitude value extracted based on the passing vibration of the rolling element detected by the sensor when the rotating device is operating normally. The monitoring apparatus according to claim 1, wherein when the difference between the amplitude value of the passing vibration of a moving body and the reference value exceeds a predetermined value, it is determined that an abnormality has occurred in the rotating device.   The reference value is an amplitude value extracted based on the passing vibration of the rolling element detected by the sensor when the rotating device is operating normally. The monitoring according to claim 1 or 2, wherein when the ratio between the amplitude value of the passing vibration of a moving body and the reference value exceeds a predetermined value, it is determined that an abnormality has occurred in the rotating device. apparatus. In a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
A sensor for detecting at least the passing vibration of the rolling element;
Based on the passing vibration of the rolling element detected by the sensor, extracting means for extracting the periodic variation;
A monitoring apparatus comprising: a determination unit that determines that an abnormality has occurred in the rotating device based on a period variation of the rolling element extracted by the extraction unit and a reference period.   The reference period is a period that is extracted based on the passing vibration of the rolling element detected by the sensor when the rotating device is operating normally, and the determination means includes the rolling element. The monitoring apparatus according to claim 4, wherein when the difference between the periodic fluctuation of the passing vibration of the motor and the reference period exceeds a predetermined value, it is determined that an abnormality has occurred in the rotating device. In a monitoring device for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
A sensor for detecting at least the passing vibration of the rolling element;
Based on the passing vibration of the rolling element detected by the sensor, extracting means for extracting the periodic variation;
Detecting means for detecting the rotational speed of the rotating body;
The ratio of the revolution speed of the rolling element extracted by the extraction means and the rotation speed of the rotating body detected by the detection means is compared with a predetermined value to determine that an abnormality has occurred in the rotating device. And a monitoring device.   The monitoring device according to claim 1, wherein the sensor includes an acceleration sensor.   The monitoring device according to claim 1, wherein the sensor includes a strain gauge. In a monitoring method for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
Detecting at least a passing vibration of the rolling element;
Extracting the amplitude value based on the detected passing vibration of the rolling element;
And a step of determining that an abnormality has occurred in the rotating device based on the extracted amplitude value of the passing vibration of the rolling element and a reference value.   The reference value is an amplitude value extracted based on the detected passing vibration of the rolling element when the rotating device is operating normally, and the amplitude value of the passing vibration of the rolling element. The monitoring method according to claim 9, further comprising: determining that an abnormality has occurred in the rotating device when a difference between the reference value and the reference value exceeds a predetermined value.   The reference value is an amplitude value extracted based on the detected passing vibration of the rolling element when the rotating device is operating normally, and the amplitude value of the passing vibration of the rolling element. 11. The monitoring method according to claim 9, wherein when the ratio to the reference value exceeds a predetermined value, it is determined that an abnormality has occurred in the rotating device. In a monitoring method for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
Detecting at least a passing vibration of the rolling element;
Extracting the periodic variation based on the detected passing vibration of the rolling element;
And a step of determining that an abnormality has occurred in the rotating device based on the extracted periodic fluctuation of the rolling element and a reference period.   The reference period is a period that is extracted based on the detected passing vibration of the rolling element when the rotating device is operating normally, and the determination means passes the rolling element. The monitoring method according to claim 12, wherein when the difference between the vibration fluctuation and the reference period exceeds a predetermined value, it is determined that an abnormality has occurred in the rotating device. In a monitoring method for monitoring a rotating device having a rotating body supported using a rolling element to be lubricated,
Detecting at least a passing vibration of the rolling element;
Extracting the periodic variation based on the passing vibration of the rolling element;
Detecting the rotational speed of the rotating body;
And a step of determining that an abnormality has occurred in the rotating device by comparing a ratio between the revolution speed of the rolling element and the rotating speed of the rotating body with a predetermined value.

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