DE4041106A1 - Rotating component monitor - in which yarn defect signals are used to identify component fault or wear automatically through an electronic circuit - Google Patents

Abstract

To determine if the rotating components which prepare and feed fibre or roving materials at a spinner are faulty or functioning incorrectly, yarn fault signals are processed by an electronic circuit. If the fault signals exceed a tolerance limit, the electronic circuit automatically checks subsequent yarn passages periodically to determine if the same or similar breach of the tolerance recurs. This gives the cause of the fault from the technical data and/or appts. setting data and/or the rotating components in terms of faulty setting, defect or wear. With a multiple defect signal pattern, at each anticipated yarn point, an automatic indication shows the faulty setting and/or the component with faulty operation or defect or wear and/or the spinning operation is stopped. To check on repeated and periodic fault signals, they are taken on a preset length tolerance plus and minus of each yarn point passing round the component once or more times, multiplied by the draft of the drawing unit between the component under scrutiny and the yarn measurement point, and also multiplied by at least the correction value for the staple length. ADVANTAGE - The technique gives a rapid, effective and economic process to identify faulty components, for immediate correction which prevents faults spreading.

Description

The invention relates to methods and devices for determining incorrectly working, faulty or damaged rotating machine parts on a the spun fiber material or Roving of a spinning device preparing and feeding Facility.

DE 32 37 371 C2 is a device for determining of fault locations on an apron drafting system of a spinning machine by evaluating one with a detector on a running one Analogue thread nonuniformity signal obtained in Form of spectra known for a certain thread length, at which the detector uses with an analog / digital converter Computer that is connected from the Thread non-uniformity signal by a Fourier transformer and a frequency-dependent spectrum a numerical integrator forms an integral value, where if one is exceeded by the maximum permissible Thread non-uniformity predetermined amplitude value of the frequency-dependent spectrum and / or one for the specific Thread length predetermined integral value triggered an alarm signal or the spinning station is stopped.  

Such a determination device is technically complex, and the frequency analysis takes a relatively long time. You want to sufficient statistical certainty of the Obtaining the fault location must be a multiple (25 to 30 times) of the maximum possible wavelength can be evaluated. Economy and effectiveness of the device are as to be judged low.

The object of the invention is to be quick, effective and economically the faulty or damaged or incorrectly working or wrong to determine the set rotating machine parts Remedy as early as possible and consequential damage prevent.

This object is achieved by an invention with the characterizing Features of claim 1 solved. Advantageous further training of the method according to the invention are in claims 2 and 3 described.

A new and inventive device to carry out the The method is described in claim 4. Beneficial Developments of the invention are in the further Subclaims described.

The particular advantages of the invention result from the following description of a also shown in the drawing Embodiment on which the invention is closer is described and explained.

Fig. 1 shows schematically a part of a spinning station of a fine spinning machine in connection with the block diagram of a device according to the invention.

Fig. 2 shows a graphical representation of the digitization of a thread signal.

Fig. 3 shows a graphical representation of a digitized thread signal.

Fig. 1 of a fine spinning machine facing away from the spinning unit 1 a the running yarn 2 a twist issuing spinning device 3 and a of the spinning device 3 upstream draft device 4 with the bottom rollers 5, 6, 7 and the top rollers 51, 61, 71. The lower roller 6 is wrapped by an apron 8 , which runs over guide devices 10 , 11 and is driven by the lower roller 6 . The upper roller 6 'is wrapped by an apron 9 , which runs over a guide device 10 ' and is driven by the upper roller 6 '.

The spinning device 3 is, for example, a false wire feeder or a pneumatic spinneret arrangement.

In the drafting system 4 , roving 13 of fineness Nm 0.47 is stretched with a total delay of 120 to such an extent that the spinning device 3 can produce a spun fiber yarn or a thread 2 of fineness Nm 56 from it. The total warping of 120 is composed of a pre-warping of 2.5 in the pre-warping field located between the roller pairs 7 , 71 and 6 , 6 'and a main warping of 48 in the main warping field. The fiber material consists of a mixture of cotton fibers with synthetic fibers .

The lower rollers 5 and 7 each have a diameter of 32 mm corresponding to a circumference of approximately 100.5 mm. The upper rollers 51 and 71 each have a diameter of 31 mm, corresponding to a circumference of approximately 97.4 mm. The lower roller 6 has a diameter of 30.5 mm, corresponding to a circumference of approximately 95.8 mm. The upper roller 6 'has a diameter of 24.8 mm, corresponding to a circumference of approximately 77.9 mm. The spinning speed is 120 m / min, corresponding to 2 m / s or 2000 mm / s.

The shafts of the lower rollers 5 , 6 and 7 pass through all spinning positions on one machine side of the fine spinning machine (not shown here). They are driven centrally. Corresponding to the spinning speed of 120 m / min, the lower roller 5 rotates at a speed of 19.9 U / s. Corresponding to the selected total distortion of 120, the lower roller 7 has a speed of 0.166 U / s. The rolling on the bottom roller 5 upper roller 5 'has a speed of about 20.5 U / s. The rolling on the lower roller 7, the upper roller 7 'has a speed of approximately 0.17 U / s. The roving 13 runs at a speed of 16 2/3 mm / s in the rear pair of rollers 7 , 7 '. Between the straps 8 and 9 , its running speed is already increased to 41 1/3 mm / s.

At the output of the spinning device 3 , a thread measuring point 14 is arranged either in front of or behind a pair of draw-off rollers, not shown here. Its essential parts consist of a light-emitting diode 15 as a light source and a photodiode 16 which measures the shading of the light source by the running thread 2 and converts it into a thread-proportional wavy DC voltage. The thread signal which is now present as measuring voltage U 1 passes via a line 17 and a measuring point switch 52 to an electronic circuit arrangement, designated overall by 18 .

The electronic circuit arrangement 18 has an AD converter operating according to the integration method with the following essential individual parts:
The AD converter has a controlled switch S 1 on the input side, which connects the input 19 of the AD converter 18 alternately to the fluctuating DC voltage U 1 representing the thread signal and to a reference voltage U 2 , which originates from a constant voltage source 20 and which is one of the Signal voltage U 1 has opposite polarity. The switch S 1 or the input 19 is connected via a resistor R of an RC element to the inverting input of a first operational amplifier A 1 . The capacitor C of the RC element connects the inverting input of the operational amplifier A 1 to its output. The output of the first operational amplifier A 1 is connected to the inverting input of a second operational amplifier A 2 connected downstream. The non-inverting inputs of both operational amplifiers A 1 , A 2 are connected to ground. The output of the second operational amplifier A 2 is connected to a computer 21 which also serves as a control device for the AD converter 18 .

The lower roller 5 is assigned a machine clock sensor 22 which correlates with its speed. The machine clock sensor 22 is connected by a line 23 to a machine clock generator 24 assigned to the computer 21 . The machine clock generator 24 ensures that between two passes of a marking 25 in front of the machine clock sensor 22 there are 100 usable pulses that can be used as counting pulses. The computer 21 is also assigned a timer 27 which, for example, supplies 10,000 pulses per second that can be used as counting pulses via the line 28 to the computer 21 .

A signal memory 32 , a counter 33 and a combination 34 of monitor and printer are connected to the computer 21 via further lines 29 , 30 , 31 .

The switch S 1 is switched over in time with the clock pulses supplied by the machine clock sensor 22 . For this purpose, the switch S 1 is connected to the computer 21 via a line 35 .

The measuring point switch S 2 is switched over by the computer 21 according to a special switching program. For this purpose, the measuring point switch S 2 is connected to the computer 21 by a line 36 .

The measuring point switch 52 connects a center contact 37 to one of the 12 contacts 38 arranged in a circle, each of which leads to the individual thread measuring points 14 of adjacent spinning positions 1 .

Several setpoint transmitters are connected to the computer 21 . The selected yarn count of the thread 2 is entered into the computer 21 by the setpoint generator 39 . The computer 21 uses a special program to determine the tolerance limits 45 , 46 of the thread signal 47 digitized by the AD converter 18, which are dependent on this fineness and are shown graphically in FIG . The setpoint generator 40 is used to input the selected delay to the computer 21 . The diameter of the top roller 5 'and the top roller 7 ' are entered into the computer by the setpoint generator 41 and 42 . Since the top rollers are in practice mounted in a load carrier of the drafting system 4 , their diameter can change by changing the load carrier. The diameters of the lower rollers, on the other hand, are fixed, so that they are already included in the program of the computer 21 as fixed values.

The setpoint generator 43 is used to input the selected spinning speed into the computer 21 . The setpoint generator 44 serves for the input of correction values, for example a correction value representing the staple length of the spinning fiber material or other correction values.

Alternatively, all specified values can also be displayed visibly on the setpoint generators and can thus be checked. Likewise, alternatively, the individual setpoint transmitters can be implemented using a conventional keyboard on the computer 21 , so that the input of the setpoints into an appropriate program on the computer 21 is carried out alphanumerically by pressing the keys on the keyboard. In this respect, the setpoints 39 to 44 can also be understood as key combinations of a keyboard.

The computer 21 is also capable of triggering a shutdown command for the spinning operation of the respective spinning device 3 via a line 48 if the tolerance limits 45 and / or 46 are frequently exceeded, possibly via a further multiplexer (not shown here). The device according to the invention works as follows: In this embodiment, for the sake of simplicity, only the lower rollers 5 and 7 and the upper rollers 5 'and 7 ' are specifically monitored. The lower roller 5 specifies the machine cycle by generating 100 counts per revolution. If its surface has an error affecting the thread 2 , for example contamination, damage or one-sided wear, it is expected that the yarn error noticeable at the thread measuring point 14 or the yarn irregularity noticeable there will repeat itself after 100 counting pulses have elapsed , i.e. after a thread travel of 100.5 mm. If, on the other hand, the fault location is on the upper roller 51 , the repetition of the interference signal is expected because of the difference in diameter after approximately 97 pulses have elapsed.

If the source of the interference is on the lower roller 7 , a repetition of the interference signal is only to be expected after 100 × 120 = 12,000 counting pulses have elapsed because the lower roller 7 rotates correspondingly more slowly because of the 120-fold delay. If, on the other hand, the fault is to be found in the upper roller 7 ', a repetition of the fault signal can be expected already after the expiration of 11,625 pulses due to the difference in diameter.

To improve the resolution of the thread unevenness signal U 1 , the machine clock 24 contains a multiplier circuit by means of which the 100 clock pulses generated per revolution of the lower roller 5 are multiplied by a factor of 1,000, so that per revolution of the lower roller 5, 26 thousand pulses are sent to the computer 21 via the line 26 . The computer 21 controls the switch S 1 according to its programming so that, according to FIG. 2, after two counting pulses have elapsed, the voltage U 1 is applied to the input 19 and thus via the resistor R to the capacitor C, and only for as long until a further 8 counts have elapsed. Then the computer 21 switches the switch S 1 to the reference voltage U 2 , the polarity of which is opposite to the voltage U 1 . From this point on, the capacitor C discharges in accordance with the time constant determined by the technical data of the RC element.

During charging, the voltage across capacitor C rises the higher the voltage U 1 is.

As soon as the voltage of the capacitor C goes through zero during discharge, the computer 21 switches the switch S 1 again, which takes a period of time during which two counting pulses occur. Then the capacitor C is recharged for 8 counts and the switching cycle is repeated.

The counter 33 counts the number of counting pulses which occur during the discharge of the capacitor C each time. The counting pulses counted in each discharge process are shown graphically in FIG. 3.

The first unloading process followed line 53 according to FIG. 2. 22 pulses were counted. The second discharge followed line 51 , 20 pulses were counted. The third discharge followed line 50 , 18 pulses were counted. The fourth discharge followed line 52 , 21 pulses were counted. The fifth unloading process followed line 54 , 24 pulses were counted. The sixth unloading process followed line 51 , again 20 pulses were counted.

The seventh unloading process exceeded the lower tolerance limit 45 . This discharge followed line 49 and only 14 pulses were counted. The computer 21 recognized the seventh unloading process as a thread defect signal and then, according to the program, caused the memory 32 to store the counting result and at the same time the counter 33 to start the following separate counting intervals for the targeted monitoring of the selected bottom and top rollers: Would the top roller 5 'cause the malfunction Question, the thread piece that is below the lower tolerance limit 45 of the thread unevenness signal 47 , which is located at the thread measuring point 14 after the expiration of 97 × 1000 counting pulses, would be specifically examined. Targeted monitoring begins about 200 pulses before the calculated value and ends about 200 pulses after the calculated value.

If the lower roller 5 were to be considered as the cause of the fault, then the targeted monitoring of the thread would have to be carried out after the passage of 100 × 1000 counts with a tolerance of ± 200 pulses.

If the top roller 7 'came into question as the cause of the fault, it is recommended to monitor that thread path which is located after the expiration of 11 625 × 1000 counts with a tolerance of, for example, ± 500 counts at the thread measuring point 14 . If the lower roller 7 could be the cause of the fault, the running thread 2 would have to be monitored specifically after the expiry of 12,000 × 1000 counting pulses with a tolerance of likewise about ± 500 pulses.

The four counting intervals mentioned are defined in the program of the computer 21 .

After passing through 12 000 x 1000 counts the electronic circuitry 18 can monitor one other spinning position in the periods between the intervals in each case. For this purpose, the measuring point switch S 2 is then switched over appropriately.

It should be noted that the targeted Monitoring periods for exceptionally short periods and that switching is not mechanical, but by electronic and therefore very low inertia Switching devices happens.

Before switching to an adjacent spinning position, the electronic circuit arrangement 18 expediently remains connected to the thread measuring point 14 without interruption until the lower roller 7 has made a full revolution. During this time, irregularities on the rollers 5 and 5 'have long been noticeable. The top roller 7 'has completed one revolution by then. Irregularities on the rollers 7 and 7 'should have made themselves known by at least one point of failure. If this is not the case, it can first be switched to an adjacent spinning station until the monitoring intervals provided for the rollers 7 and 7 'are approaching. Given the conditions, it takes about 6 seconds for the lower roller 7 to make a full revolution. This time can be used, for example, in rapid succession in turn, all to monitor the front rollers of the drafting of the channel selector S 2 connected spinning units specifically with the possibility under the circumstances, the bottom roller 5 to let each make 8 to 9 rotations at each measurement cycle.

In this way, the most important ones are obtained very quickly Monitoring results regarding the rapidly running and therefore front rollers particularly susceptible to wear. Then you can Rear rollers are monitored specifically and this Monitoring cycles can turn advantageous from time to time be interrupted to monitor the front rollers again.

After the result of the seventh switching step, namely the numerical value 14 , is stored in the memory 32 , the upper tolerance limit 46 is only exceeded in the fourteenth switching step according to FIG. 3. The discharge of the capacitor C follows the line 55 shown in FIG. 2, and 28 counts are counted. This exceedance is also recorded in the memory 32 , and when this is exceeded the counter 33 starts a new series of the monitoring cycles mentioned above, which run in addition to the cycles started first.

The counter 33 is set up and the computer is programmed so that a plurality of monitoring cycles can run simultaneously.

As soon as the same or similar defect signals, such as the defect signals 56 and 57 indicated in FIG. 3, correlate several times in the course of the monitoring cycles, the computer 21 determines the source of the fault that is likely to be suspected according to the principles developed above and displays it on the monitor 34 . where the individual levels of the counter 32 and / or the memory contents of the memory 33 are also displayed and, if necessary, can be printed out on request by a printer assigned to the monitor 34 . If necessary, the computer 21 can simultaneously trigger a shutdown command for the spinning operation via the line 48 .

The input of correction values via the setpoint generator 44 may be necessary, for example, to stretch the intervals if, for example, the spinning speed does not match the circumferential speed of the lower roller 5 exactly.

In the exemplary embodiment according to FIG. 1, the computer 21 was included in the direct control of the AD converter 18 . Since this has decisive advantages, there is a circuit that goes beyond the circuit of commercially available AD converters.

The device also offers the possibility of using the time cycle instead of the machine cycle, which can be supplied, for example, by the clock generator 27 with a cycle rate of 100,000 pulses / s. In this case, the time monitoring intervals would be the same at the same spinning speed. However, the use of the machine cycle offers the advantage of independence from more or less large changes or fluctuations in the spinning speed.

If the straps 8 and 9 or the rollers 6 and 6 'are also to be included in the monitoring, the procedure to be followed is the same as that described above. Under the given conditions, the speed of the lower roller 6, for example, is approximately 0.415 mm / s.

If the drafting device 4 is set incorrectly, the thickness fluctuations of the spun thread known as "distortion waves", the wavelength of which can be calculated beforehand or empirically determined beforehand, result depending on the stack length set on the setpoint generator 44 and the delay set on the setpoint generator 40 . When it occurs, a special signal "drafting system set incorrectly" is given with appropriate programming of the circuit arrangement 18 .

Claims (15)

1. A method for determining malfunctioning, faulty or damaged rotating machine parts on a device processing and supplying the spun fiber material or roving of a spinning device, characterized in that with the aid of an electronic circuit arrangement, automatically when a tolerance limit of a thread signal obtained from the running spun thread is exceeded (defect signal ) the checking of all of the subsequent thread sections for periodic recurrence of a similar or similar excess is initiated, in which the thread defect is likely to result from the technical data and / or setting data of the device and / or its rotating parts in the event of their incorrect setting, defect or wear periodic recurrence should result, and that after repeated occurrence of the defect signal at the expected location of the thread automatically an indication of the faulty E setting of the device and / or on the particular faulty, defective or worn machine part is displayed and / or the spinning operation is stopped. 2. The method according to claim 1, characterized in that the Check for periodic return of the defect signal with a specified length tolerance according to plus and minus at that point in the running thread, which after passing one of the scope or a Multiples of the circumference of the particular rotating Machine part multiplied by that between the  certain machine part and the thread measuring point if there is any delay determined thread length located in front of the thread measuring point. 3. The method according to claim 1 or 2, characterized in that the periodic review of the Defect signal with a predetermined length tolerance Plus and minus at that point of the running thread is made after passing one out of the Scope or a multiple of the scope of the particular rotating machine part multiplied by that between the specific machine part and the thread measuring point if there is any delay and multiplied by one representing at least the stack length Correction value determined thread distance before the Thread measuring point is located. 4. Means for determining malfunctioning, faulty or damaged rotating machine parts ( 5 , 5 ', 7 , 7 ') on a the spun fiber material or roving ( 13 ) of a spinning device ( 3 ) processing and feeding device ( 4 ) for executing the method According to one of claims 1 to 3, characterized in that a thread non-uniformity signal (U 1 ) sensor ( 16 ) is arranged at a thread measuring point ( 14 ) and is connected to an electronic circuit arrangement ( 18 ) in which tolerance limits ( 45 , 46 ) of the thread non-uniformity signal (U 1 , 47 ) can be determined, if they are exceeded after plus or minus a defect signal ( 56 ', 57 ) occurs, when triggered by a computer ( 21 ) or a corresponding control device, a targeted monitoring of those points of the running thread ( 2 ) is triggered on which in the event of incorrect setting or in the event of a defect or misc leiß on one of the rotating machine parts ( 5 , 5 ', 7 , 7 ') with a repetition of the thread defect signal ( 56 , 57 ) is to be expected that if a thread defect signal ( 56 , 57 ) occurs several times in succession, the expected places Device ( 4 ) and / or the relevant machine part ( 5 , 5 ', 7 , 7 ') by a connected to the computer ( 21 ) or to the corresponding electronic control device reporting and / or display device ( 34 ) set as faulty, defective or is reported worn or displayed, and / or that in this case the computer ( 21 ) or the corresponding control device triggers a shutdown command for the spinning operation of the spinning device ( 3 ). 5. Device according to claim 4, characterized in that the electronic circuit arrangement ( 18 ) or the computer ( 21 ) or the corresponding control device at least one signal memory ( 32 ), at least one counter ( 33 ) and at least one electronic clock ( 24 , 27 ) having. 6. Device according to claim 4 or 5, characterized in that the computer ( 21 ) or the corresponding control device setpoint generator ( 39 to 44 ) for the specification of each with a specific rotating machine part to be monitored ( 5 , 5 ', 7 , 7 ' ) correlating thread sections to be monitored specifically after the occurrence of a thread defect signal ( 56 , 57 ). 7. Device according to one of claims 4 to 6, characterized in that the specifically monitored thread sections from the product of the circumference of the rotating machine part ( 5 , 5 ', 7 , 7 ') and optionally between this machine part ( 5 , 5 ', 7 , 7 ') and the measuring point ( 14 ) existing delay according to the program in the electronic circuitry ( 18 ), the computer ( 21 ) or the corresponding control device and that the setpoint generator ( 39 to 44 ) for this purpose at least for specifying the yarn count Determination of the tolerance limits ( 45 , 46 ) of the thread signal ( 47 ), the delay and, if appropriate, also for the variable specification of the diameter or circumference of individual rotating machine parts ( 5 ', 7 ') and / or the specification of the spinning speed and / or the specification of a the stack length representing and / or another correction value are set up. 8. Device according to one of claims 4 to 7, characterized in that at least one of the rotating machine parts ( 5 ) with the speed of this machine part ( 5 ) correlating machine clock sensor ( 22 ) is assigned to the computer ( 21 ) or the corresponding control device serves as a clock or is connected to your clock ( 24 ). 9. Device according to one of claims 4 to 8, characterized in that the electronic circuitry ( 18 ) for the successive monitoring of a plurality of parallel spinning devices ( 1 , 3 ) is set up and for this purpose with an automatically controllable measuring point switch (S 2 ) for the thread measuring points ( 14 ) of the individual spinning devices ( 1 , 3 ) are equipped. 10. The device according to claim 9, characterized in that circuitry measures are taken, which cause that another spinning device during the times when a spinning device ( 1 , 3 ) does not have to be expected with a periodic return of a defect signal is monitored. 11. Device according to one of claims 4 to 10, characterized in that the electronic circuit arrangement ( 18 ) has an AD converter operating according to the integration method. 12. The device according to claim 11, characterized in that the AD converter ( 18 ) on the input side has a controlled switch (S 1 ), the input ( 19 ) of the AD converter ( 18 ) alternately to a fluctuating representing the thread signal DC voltage (U 1 ) and to a reference voltage (U 2 ) that the switch (S 1 ) via the resistor (R) of an RC element to the inverting input of a first operational amplifier (A 1 ) of the AD converter ( 18 ) is connected that the capacitor (C) of the RC element connects the inverting input of the operational amplifier (A 1 ) with its output, that the non-inverting inputs of the operational amplifier (A 1 ) and possibly one or more other operational amplifiers (A 2 ) of the AD converter ( 18 ) are connected to ground and that the output of the last amplifier (A 2 ) is connected to the computer ( 21 ) or a corresponding control device, which is part of the AD-W andlers ( 18 ). 13. The device according to claim 12, characterized in that the switching of the switch (S 1 ) is preferably carried out in time with the clock pulses supplied by the machine clock ( 22 ) and that the switch (S 1 ) to the computer ( 21 ) or the corresponding Control device is connected. 14. Device according to claim 12 or 13, characterized in that the switching of the measuring point switch (S 2 ) according to a special switching program by the computer ( 21 ) or the control device and that the measuring point switch (S 2 ) also to the computer ( 21 ) or is connected to the corresponding control device. 15. The device according to claim 14, characterized in that in the switching program is provided either to switch the switch (S 2 ) after the expiry of a certain number of clock pulses of a timer or the machine clock to another thread measuring point of another spinning device, or that the changeover to another thread measuring point takes place during the times when a periodic return of a defect signal need not be expected in the spinning device ( 1 , 3 ) being monitored.