JP2019109082A - State diagnosis apparatus for motion guide device - Google Patents

Abstract

To highly accurately diagnose a state of a motion guide device having track members and movement members.SOLUTION: A parameter acquisition section acquires a predetermined diagnostic parameter correlated with a friction force fluctuation to occur when movement members move on track members in a motion guide device. A signal processing section extracts a first diagnostic signal being the signal of a first predetermined frequency band and a second diagnostic signal being the signal of a second predetermined frequency band that is lower than the first predetermined frequency band, from a signal related to a predetermined diagnostic parameter. A diagnosis section diagnoses a state of the motion guide device on the basis of the first diagnostic signal and the second diagnostic signal.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a state diagnostic device that diagnoses the state of a motion guide device having a track member and a moving member.

  Heretofore, there has been known a motion guiding device having a track member extending along a longitudinal direction and a movable member relatively movable along the longitudinal direction of the track member. In this motion guide device, the plurality of rolling elements are rollably held between the rolling surface formed on the raceway member, and the moving member is engaged with the raceway member. And a circulation way for a plurality of rolling elements to circulate is formed inside a movement member. Thereby, when the moving member moves along the longitudinal direction of the track member, the plurality of rolling elements circulate on the rolling surface of the track member and the inside (circulation path) of the moving member.

  In addition, in Patent Document 1, in the motion guide device (motion mechanism) as described above, the rolling surface of the track member ("track member" in Patent Document 1) ("rolling member rolling surface" in Patent Document 1) A technique related to an inspection apparatus for inspecting the damage of In the inspection device described in Patent Document 1, an acceleration sensor is installed on the track body. Then, the band pass filter acquires a detection signal of a specific frequency band from the detection signal of the acceleration sensor, and compares the intensity of the acquired detection signal with a predetermined threshold to diagnose the degree of damage to the rolling surface.

Unexamined-Japanese-Patent No. 2010-96541

  In the motion guiding device, when the moving member moves along the longitudinal direction of the track member, a frictional force is generated between the rolling surface of the track member and the plurality of rolling elements rolling on the rolling surface. (Dynamic friction force) occurs. Here, the state of the rolling surface of the raceway member is different at each position along the longitudinal direction. As a result, the magnitude of the frictional force generated between the rolling surface and the rolling element varies depending on the position of the moving member on the raceway member. Therefore, when the moving member moves along the longitudinal direction of the track member, the frictional force fluctuation occurs. Then, when the state of the rolling surface of the raceway member changes due to the occurrence of flaking or the like, the fluctuation of the frictional force generated when the moving member moves along the raceway member also changes. Therefore, it is possible to diagnose the state (the degree of deterioration or damage of the rolling surface of the raceway member) of the rolling surface of the raceway member in the motion guide device by acquiring the parameter correlated with the friction force fluctuation.

  However, in the motion guide device, not only the frictional force fluctuation occurs due to the rolling element rolling on the rolling surface of the raceway member, but the circulation of the rolling member on the raceway member and the moving member Frictional force fluctuations also occur when the rolling elements move in and out of the path. Then, in the motion guide device, when a change in a specific state occurs, the rolling of the race member is caused more than the friction force fluctuation caused by the rolling of the rolling element on the rolling surface of the race member. In some cases, the variation in the frictional force caused by the rolling elements moving in and out between the surface and the circulation path of the moving member may change more significantly.

The present invention has been made in view of the above-described points, and an object thereof is to provide a technology capable of diagnosing the state of a motion guide device having a track member and a moving member with higher accuracy. Do.

According to the present invention, there is provided a state diagnostic device for a motion guidance device,
A plurality of rolling members are provided between a track member extending along a longitudinal direction and a moving member relatively movable along the longitudinal direction of the track member, the rolling surface being formed on the track member A moving member configured to be capable of rolling the movable body, engaged with the track member, and configured to circulate the plurality of rolling elements through a circulation passage formed therein; A condition diagnostic device for diagnosing the condition of the motion guide device,
A parameter acquisition unit for acquiring a predetermined diagnostic parameter correlated with a frictional force fluctuation generated when the moving member moves in the longitudinal direction of the track member in the motion guide device;
A signal processing unit that processes a signal related to the predetermined diagnostic parameter acquired by the parameter acquisition unit, wherein a first diagnostic signal that is a signal of a first predetermined frequency band from the signal related to the predetermined diagnostic parameter And a signal processing unit that extracts a second diagnostic signal that is a signal of a second predetermined frequency band lower than the first predetermined frequency band.
A diagnosis unit that diagnoses the state of the exercise guide apparatus based on the first diagnosis signal and the second diagnosis signal extracted by the signal processing unit;
Equipped with

  According to the present invention, it is possible to diagnose the state of the motion guide device having the track member and the moving member with higher accuracy.

It is a figure showing the schematic structure of the linear motor type drive system concerning an example. It is an appearance perspective view of a rail and a block in a movement guide device concerning an example. It is a figure which shows the internal structure of the block in the exercise | movement guide apparatus which concerns on an Example. It is a block diagram showing each functional part in a diagnostic device concerning an example. It is a figure which shows the position deviation according to the position (command value) of the table based on an Example. It is a figure which shows the signal for 1st diagnosis extracted by the signal processing part which concerns on an Example. It is a figure which shows the signal for 2nd diagnosis extracted by the signal processing part which concerns on an Example. It is a figure which shows an example of transition of the amplitude of each signal when a flaking generate | occur | produces in the rolling surface of a rail in a movement guide apparatus based on an Example. It is a figure which shows an example of transition of the amplitude of each signal when damage to a ball generate | occur | produces in a movement guide apparatus based on an Example. It is a figure which shows an example of transition of the amplitude of each signal when preload loss generate | occur | produces in an exercise | movement guide apparatus based on an Example. It is a flow chart which shows a flow of state diagnosis of an exercise guidance device performed by a diagnostic device concerning an example. It is a figure which shows the feedback thrust according to the position (command value) of a table based on the modification 1 of an Example. It is a figure which shows an example of transition of the amplitude of each signal when flaking generate | occur | produces in the rolling surface of a rail in the exercise | movement guide apparatus based on the modification 1 of an Example. It is a figure which shows an example of transition of the amplitude of each signal when damage to a ball generate | occur | produces in the movement guide apparatus based on the modification 1 of an Example. It is a figure which shows an example of transition of the amplitude of each signal at the time of precompression loss generate | occur | producing in the exercise guide apparatus based on the modification 1 of an Example. It is a figure which shows schematic structure of the linear motor type drive system which concerns on the modification 2 of a present Example.

  In the state diagnostic device of the motion guide apparatus according to the present invention, the parameter acquisition unit is a predetermined diagnostic parameter correlated with the frictional force fluctuation generated when the moving member moves in the longitudinal direction of the track member in the motion guide apparatus. It is acquired. Furthermore, the signal relating to the predetermined diagnostic parameter acquired by the parameter acquiring unit is processed by the signal processing unit, whereby the first diagnostic signal and the second diagnostic signal are extracted. Here, the first diagnostic signal is a signal of a first predetermined frequency band, and the second diagnostic signal is a signal of a second predetermined frequency band lower than the first predetermined frequency band.

  As described above, in the friction force fluctuation in the motion guide device, the friction force fluctuation caused by the rolling of the rolling elements on the rolling surface of the raceway member (hereinafter also referred to as “first friction force fluctuation”) Not only) but also the friction force fluctuation (hereinafter referred to as “the second friction force fluctuation”) caused by the rolling element moving in and out between the rolling surface of the raceway member and the circulating path of the moving member. Also included). And the main frequency band differs in the 1st frictional force fluctuation and the 2nd frictional force fluctuation. In particular, the main frequency band of the second friction force fluctuation is lower than the main frequency band of the first friction force fluctuation. Therefore, in the present invention, the first diagnostic signal and the second diagnostic signal having different frequency bands are extracted from the signal relating to the predetermined diagnostic parameter correlated with the frictional force fluctuation. In this way, it is possible to separate and acquire two parameters correlated with each of the frictional force variations different in the generation factor.

  Then, in the present invention, the diagnosis unit diagnoses the state of the exercise guide apparatus based on both the first diagnostic signal and the second diagnostic signal. According to this, when a change in a state occurs in which at least one of the first frictional force fluctuation and the second frictional force fluctuation occurs in the motion guiding device, the change in the state can be detected. . Therefore, it is possible to diagnose the state of the motion guide device with higher accuracy.

  Hereinafter, specific embodiments of the present invention will be described based on the drawings. The dimensions, materials, shapes, relative arrangements, and the like of the components described in the present embodiment are not intended to limit the technical scope of the invention to them unless otherwise specified.

<Example>
(Schematic configuration of system)
FIG. 1 is a view showing a schematic configuration of a linear motor drive system according to the present embodiment. Further, FIGS. 2 and 3 are diagrams for explaining a schematic configuration of a motion guide device provided in the linear motor drive system according to the present embodiment.

  As shown in FIG. 1, the linear motor drive system 1 according to the present embodiment includes a linear motor 2, a motion guide device 3, a table 4, a linear scale 5, a base member 7, a control device 10, and a diagnostic device 200. ing. The linear motor 2 has a stator 21 and a mover 22. The stator 21 is fixed to the base member 7, and the mover 22 axially moves on the stator 21. Then, the linear motor 2 is controlled by the control device 10. Further, a table 4 for mounting a work is attached to the mover 22 of the linear motor 2. Therefore, when the mover 22 moves in the axial direction of the stator 21, the table 4 also moves accordingly.

The motion guiding device 3 is a device for guiding the movement of the table 4 along with the movement of the mover 22 in the linear motor 2 while supporting the table 4. The motion guide device 3 has a pair of rails 31 and four blocks 32. The two rails 31 extend in the axial direction of the stator 21 of the linear motor 2 and are fixed to the base member 7 so as to be parallel to each other with the stator 21 interposed therebetween. Two blocks 32 relatively moving along the longitudinal direction of the rail 31 are attached to each rail 31.

  FIG. 2 is an external perspective view of the rail 31 and the block 32 in the motion guiding device 3. FIG. 3 is a diagram showing the internal structure of the block 32. As shown in FIG. In FIGS. 2 and 3, only one block 32 attached to one rail 31 is illustrated. The block 32 is attached to the rail 31 with a plurality of balls 34 serving as rolling elements interposed therebetween. Upper and lower two rolling surfaces 31 a are formed on both side portions of the rail 31. The rolling surface 31 a is a surface on which the ball 34 rolls while being in contact with the block 32 when the block 32 moves in the longitudinal direction of the rail 31. The block 32 is engaged with the rail 31 by interposing a plurality of balls 34 in a rollable state between the rail 31 and a rolling surface 31 a formed on the rail 31.

  Further, the block 32 includes a block body 32a and two lid members 32b attached to the front and rear ends of the block body 32a in the moving direction. And in the block main body 32a and each lid member 32b, the circulation path 33 for circulating the some ball 34 is formed in the position corresponding to each rolling surface 31a formed in the rail 31. As shown in FIG. Then, when the block 32 moves on the rail 31 in the direction of the white arrow in FIG. 3, the plurality of balls 34 pass through the rolling surface 31 a of the rail 31 and the circulation path 33 inside the block 32. Circulate in the direction. That is, when the block 32 moves on the rail 31, the plurality of balls 34 move in and out between the rolling surface 31 a of the rail 31 and the circulation path 33 of the block 32.

  The table 4 is being fixed to each block 32 of the exercise | movement guide apparatus 3 comprised as mentioned above. Thus, when the table 4 moves with the movement of the mover 22 in the linear motor 2, each block 32 in the motion guide device 3 moves along the longitudinal direction of each rail 31 to guide the movement of the table 4. Do.

  Further, in the linear motor drive system 1, the position of the table 4 (the position of the linear motor 2 in the axial direction of the stator 21) is detected by the linear scale 5. The linear scale 5 is electrically connected to the controller 10. Then, the positional information of the table 4 detected by the linear scale 5 is feedback to the control device 10. Further, the thrust of the linear motor 2 is also fed back to the control device 10 from the linear motor 2. The control device 10 is configured to include a servo amplifier and a computer, and controls the linear motor 2 based on the position information of the table 4 fed back from the linear scale 5 and the thrust fed back from the linear motor 2. .

  Further, the linear motor drive system 1 is provided with a diagnostic device 200 that diagnoses the state of the motion guide device 3. FIG. 4 is a block diagram showing each functional unit in the diagnostic device 200. As shown in FIG. As shown in FIG. 4, the diagnostic procedure 20 includes a parameter acquisition unit 210, a signal processing unit 220, and a diagnosis unit 230. In the diagnostic device 200, each functional unit is realized by the computer executing a predetermined program. However, some or all of the functional units in the diagnostic device 200 may be realized by a hardware circuit. Details of the functions of the functional units in the diagnostic device 200 will be described later.

In the present embodiment, the rails 31 in the motion guide device 3 correspond to the track members according to the present invention, the blocks 32 correspond to the moving members according to the present invention, and the balls 34 correspond to the rolling elements according to the present invention. Equivalent to. Further, in the present embodiment, the linear motor 2 corresponds to the actuator according to the present invention. The actuator according to the present invention is not limited to a linear motor, and may be a ball screw or the like. Further, in the present embodiment, the control device 10 corresponds to the control device according to the present invention, and the linear scale 5 corresponds to the position information acquisition device according to the present invention.

(Status diagnosis)
Next, the state diagnosis of the motion guiding device 3 performed by the diagnostic device 200 will be described. In the motion guide device 3, as the table 4 is moved by the linear motor 2, friction force fluctuation occurs when the block 32 moves in the longitudinal direction of the rail 31. Then, when the state of the motion guide device 3 changes, a change occurs in the frictional force fluctuation. Therefore, the diagnostic device 200 diagnoses the state of the motion guide device 3 based on a predetermined diagnostic parameter that is correlated with the frictional force fluctuation.

  When the state diagnosis of the motion guide device 3 is performed by the diagnostic device 200, the linear motor 2 is driven. As a result, the table 4 moves with the mover 22 in the linear motor 2, and the block 32 moves on the rail 31 accordingly. Here, when the linear motor 2 is driven, a command value regarding the position of the table 4 (that is, the position of the mover 22) is output from the control device 10 to the linear motor 2. However, as described above, when the block 32 moves on the rail 31 along with the movement of the table 4 by the linear motor 2, the frictional force fluctuation occurs. And this friction force fluctuation becomes a disturbance, and a difference arises between the command value outputted from the control device 10 to the linear motor 2 and the actual position of the table 4. Therefore, the difference between the command value relating to the position of the table 4 output from the control device 10 to the linear motor 2 and the detection value of the linear scale 5 has a value correlated with the friction force fluctuation in the motion guide device 3.

  Therefore, in the diagnostic device 200, the parameter acquisition unit 210 controls, as a predetermined diagnostic parameter for diagnosing the state of the motion guide device 3, a position deviation regarding the position of the table 4 when the linear motor 2 is driven. Get from 10 The positional deviation is a difference between the command value regarding the position of the table 4 output from the control device 10 to the linear motor 2 and the detection value of the linear scale 5. Since the block 32 of the motion guiding device 3 moves together with the table 4, this positional deviation can be regarded as a positional deviation with respect to the block 32. In the control device 10, when the linear motor 2 is driven, the position deviation is based on the command value output to the linear motor 2 and the detected value fed back from the linear scale 5 in a predetermined operation cycle. It is calculated repeatedly. Then, the calculated positional deviation is associated with the command value output to the linear motor 2, and is output from the control device 10 to the parameter acquisition unit 210 of the diagnostic device 200.

  FIG. 5 is a diagram showing the positional deviation according to the position (command value) of the table 4 acquired by the parameter acquisition unit 210. As shown in FIG. 5, when the linear motor 2 is driven, the fluctuation of the frictional force in the motion guiding device 3 appears as a fluctuation of the position deviation. Therefore, when a change in the frictional force change occurs due to a change in the state of the motion guide device 3, a change also appears in the change in the positional deviation.

Here, in the motion guide device 3, when the block 32 moves on the rail 31, the friction force fluctuation (first friction force) caused by the balls 34 rolling on the rolling surface 31 a of the rail 31. Fluctuation) and friction force fluctuation (second friction force fluctuation) caused by the ball 34 moving in and out between the rolling surface 31a of the rail 31 and the circulation path 33 of the block 32 may occur. And depending on the mode of change of the state of movement guidance device 3, one of the 1st frictional force fluctuation and the 2nd frictional force fluctuation may change more notably compared with the other. Therefore, in the diagnostic device 200, the first diagnostic signal correlated with the first frictional force fluctuation and the second frictional force fluctuation from the signal relating to the position deviation acquired by the parameter acquiring unit 210 as shown in FIG. The signal processing unit 220 processes the signal relating to the positional deviation so as to extract the second diagnostic signal having a correlation with.

  Specifically, the signal processing unit 220 extracts the first diagnostic signal as a signal of the first predetermined frequency band from the signal relating to the position deviation, and a signal of the second predetermined frequency band lower than the first predetermined frequency band. And the second diagnostic signal is extracted. Here, the main frequency band of the second friction force fluctuation generated in the motion guide device 3 is lower than the main frequency band of the first friction force fluctuation. Further, in the present embodiment, the first predetermined frequency band is set to the frequency band of the first frictional force fluctuation, and the second predetermined frequency band is set to the frequency band of the second frictional force fluctuation. Thus, the first diagnostic signal can be extracted as a parameter correlated with the first frictional force fluctuation, and the second diagnostic signal can be extracted as a parameter correlated with the second frictional force fluctuation.

  FIG. 6 is a diagram showing the first diagnostic signal extracted by the signal processing unit 220. As shown in FIG. Such a first diagnostic signal can be extracted by processing the signal relating to the positional deviation shown in FIG. 5 with a high pass filter. FIG. 7 is a diagram showing a second diagnostic signal extracted by the signal processing unit 220. Such a second diagnostic signal can be extracted by processing a signal relating to the positional deviation shown in FIG. 5 with a low pass filter or a band pass filter. The low pass filter or the band pass filter at this time may be set to extract, for example, a component of a wavelength corresponding to the diameter of the ball 34 or twice the diameter.

  Then, in the diagnostic device 200, the diagnostic unit 230 diagnoses the state of the exercise guiding device 3 based on the first diagnostic signal and the second diagnostic signal extracted by the signal processing unit 220. Specifically, when the state of the motion guide device 3 changes, the amplitude of the first frictional force fluctuation and the amplitude of the second frictional force fluctuation change. Therefore, when the state of the motion guide device 3 changes, the amplitude of the first diagnostic signal as shown in FIG. 5 and the amplitude of the second diagnostic signal as shown in FIG. 6 change. Therefore, the diagnosis unit 230 calculates the average value of the amplitudes of the first diagnosis signal and the second diagnosis signal extracted by the signal processing unit 220 in a predetermined period. Then, the state of the exercise guiding apparatus 3 is diagnosed by comparing each of the average value of the amplitude of the first diagnostic signal and the average value of the amplitude of the second diagnostic signal with a predetermined upper limit value and a predetermined lower limit value.

  8, 9 and 10 show changes in the amplitude (average value in a predetermined period) of each of the first diagnostic signal and the second diagnostic signal according to the change in the state of the exercise guiding apparatus 3 according to the present embodiment. FIG. In FIG. 8, FIG. 9, and FIG. 10, the horizontal axis represents the number of days of use of the linear motor drive system 1, and the vertical axis represents the amplitude of the signal. In FIGS. 8, 9, and 10, the solid line L1 indicates the transition of the amplitude of the first diagnostic signal, and the dashed-dotted line L2 indicates the transition of the amplitude of the second diagnostic signal. Moreover, in FIG.8, FIG.9, FIG.10, dPmax has shown the predetermined | prescribed upper limit, and dPmin has shown the predetermined lower limit. The predetermined upper limit dPmax is determined to be abnormal if the motion guide device 3 is abnormal if at least one of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal exceeds the predetermined upper limit dPmax. It is preset as a value to be done. In addition, when at least one of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal falls below the predetermined lower limit dPmin, the predetermined lower limit dPmin is abnormal in the state of the motion guidance device 3 Is set in advance as a value to be diagnosed. Note that different predetermined upper limit values and predetermined lower limit values may be set for each of the first diagnostic signal and the second diagnostic signal.

FIG. 8 shows an example of the transition of the amplitude of each signal when flaking occurs on the rolling surface 31 a of the rail 31 in the motion guiding device 3. In this case, when the number of days of use of the linear motor drive system 1 reaches D1, the amplitude (L1) of the first diagnostic signal reaches the predetermined upper limit dPmax. However, at this point in time, the amplitude (L2) of the second diagnostic signal is a value within the normal range (that is, a range not less than the predetermined lower limit dPmin and not more than the predetermined upper limit dPmax). That is, in this case, along with the flaking of the rolling surface 31 a of the rail 31, it is considered that the first frictional force fluctuation is significantly changed more than the second frictional force fluctuation. Even in such a case, the state diagnosis of the motion guiding apparatus 3 by comparing the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with the predetermined lower limit dPmin and the predetermined upper limit dPmax. By performing the above, immediately after the number of days of use of the linear motor drive system 1 exceeds D1, it can be diagnosed that the state of the motion guide device 3 is abnormal.

  FIG. 9 shows an example of the transition of the amplitude of each signal when damage to the ball 34 occurs in the motion guide device 3. In this case, when the number of days of use of the linear motor drive system 1 has reached D2, the amplitude (L2) of the second diagnostic signal has reached a predetermined upper limit dPmax. However, at this point in time, the amplitude (L1) of the first diagnostic signal is a value within the normal range. That is, in this case, it is considered that, with the damage of the ball 34 in the motion guide device 3, the second frictional force fluctuation is significantly changed more than the first frictional force fluctuation. Even in such a case, the state diagnosis of the motion guiding apparatus 3 by comparing the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with the predetermined lower limit dPmin and the predetermined upper limit dPmax. By performing the above, immediately after the number of days of use of the linear motor drive system 1 exceeds D2, it can be diagnosed that the state of the motion guide device 3 is abnormal.

  FIG. 10 shows an example of the transition of the amplitude of each signal when drop in preload applied to the plurality of balls 34 (hereinafter referred to as “preload loss”) occurs in the block 32 of the motion guide device 3 . In this case, when the number of days of use of the linear motor drive system 1 reaches D3, the amplitude (L1) of the first diagnostic signal reaches the predetermined lower limit dPmin. However, at this time, the amplitude (L2) of the second diagnostic signal is a value within the normal range. That is, in this case, it is considered that the first frictional force fluctuation is significantly changed more than the second frictional force fluctuation along with the preload loss in the motion guide device 3. Even in such a case, the state diagnosis of the motion guiding apparatus 3 by comparing the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with the predetermined lower limit dPmin and the predetermined upper limit dPmax. By performing the above, immediately after the number of days of use of the linear motor drive system 1 exceeds D3, it can be diagnosed that the state of the motion guide device 3 is abnormal.

  As can be seen from the transition of the amplitude (L1) of the first diagnostic signal and the amplitude (L2) of the second diagnostic signal shown in FIGS. 8, 9, and 10, the amplitude of one of the signals is from the normal range The amplitude of the other signal may fall within the normal range even if it is deviated. Therefore, if the state diagnosis of the exercise guiding device 3 is performed based on any one of the first diagnostic signal and the second diagnosis signal, the exercise guidance may be performed depending on the mode of the abnormal state of the exercise guiding device 3. There is a possibility that the state of the exercise guide device 3 may be misdiagnosed as normal although the state of the device 3 is an abnormal state to be diagnosed. On the other hand, according to the diagnostic device 200 of the present embodiment, the motion guidance is performed by comparing each of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with a predetermined lower limit value and a predetermined upper limit value. In order to diagnose the state of the device 3, the state of the motion guide device 3 can be diagnosed with higher accuracy. In addition, as shown in FIGS. 8, 9, and 10, the correlation between the mode of the abnormal state of the motion guiding device 3 and the manner of the change of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal is If it is determined in advance based on experiments etc., it is also possible to estimate the aspect of the abnormal state of the motion guiding device 3 based on changes in the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal (ie, friction It is possible to estimate the factor of change in force fluctuation).

(Diagnostic flow)
Here, the flow of the state diagnosis of the exercise guiding apparatus 3 executed by the diagnosis apparatus 200 will be described based on the flowchart shown in FIG. This flow is executed by the diagnostic device 200 at a predetermined frequency (for example, once a day).

  In the present flow, first, in S101, the positional deviation calculated in the control device 10 when the linear motor 2 is driven is associated with the position (command value) of the table 4 and acquired. Next, in S102, the above-described filtering process is performed on the signal relating to the positional deviation acquired in S101, whereby the first diagnostic signal and the second diagnostic signal are extracted. Next, in S103, the amplitude dP1 of the first diagnostic signal and the amplitude dP2 of the second diagnostic signal are calculated. As described above, each of the amplitudes dP1 and dP2 of each signal is calculated as an average value in a predetermined period.

  Next, in S104, it is determined whether the amplitude dP1 of the first diagnostic signal is equal to or greater than a predetermined lower limit dPmin and equal to or less than a predetermined upper limit dPmax. That is, it is determined whether or not the amplitude dP1 of the first diagnostic signal is a value within the normal range. If an affirmative determination is made in S104, then it is determined in S105 whether the amplitude dP2 of the second diagnostic signal is greater than or equal to a predetermined lower limit dPmin and less than or equal to a predetermined upper limit dPmax. That is, it is determined whether or not the amplitude dP2 of the second diagnostic signal is a value within the normal range. If an affirmative determination is made in S105, then it is determined in S106 that the state of the exercise guiding apparatus 3 is normal. On the other hand, when a negative determination is made in S104 or S105, it is next determined in S107 that the state of the motion guiding device 3 is abnormal.

(Modification 1)
Hereinafter, modification 1 of state diagnosis of movement guidance device 3 performed by diagnostic device 200 is explained. In the above embodiment, the positional deviation is used as a predetermined diagnostic parameter correlated with the friction force fluctuation in the motion guiding device 3. Here, as described above, in the linear motor 2, the actual thrust of the linear motor 2 is fed back to the control device 10. Then, the actual thrust of the linear motor 2 fluctuates according to the friction force fluctuation in the motion guiding device 3. Therefore, the thrust (hereinafter referred to as “feedback thrust”) of the linear motor 2 fed back to the control device 10 is correlated with the friction force fluctuation in the motion guide device 3. So, in this modification, it replaces with position deviation and uses feedback thrust as a predetermined diagnostic parameter in state diagnosis of movement guidance device 3. FIG.

  In the present modification, the feedback thrust when driving the linear motor 2 is acquired from the control device 10 by the parameter acquisition unit 210 of the diagnosis device 200. At this time, the feedback thrust is output from the control device 10 to the parameter acquisition unit 210 in association with the command value output to the linear motor 2. FIG. 12 is a diagram showing the feedback thrust according to the position (command value) of the table 4 acquired by the parameter acquisition unit 210. As shown in FIG. 12, when the linear motor 2 is driven, the fluctuation of the frictional force in the motion guiding device 3 appears as the fluctuation of the feedback thrust. Therefore, if a change occurs in the frictional force fluctuation due to a change in the state of the motion guide device 3, a change also appears in the fluctuation of the feedback thrust.

  And in this modification, as shown in FIG. 12, the signal processing unit 220 extracts the first diagnostic signal and the second diagnostic signal from the signal related to the feedback thrust acquired by the parameter acquisition unit 210. Process signals related to thrust. Also in this case, as in the above embodiment, the first diagnostic signal is a signal of a first predetermined frequency band, and the second diagnostic signal is a signal of a second predetermined frequency band. Thus, the first diagnostic signal can be extracted as a parameter correlated with the first frictional force fluctuation, and the second diagnostic signal can be extracted as a parameter correlated with the second frictional force fluctuation.

And also in the case of this modification, when the state of the motion guide device 3 changes, the amplitude of the first diagnostic signal and the amplitude of the first frictional force fluctuation change with the amplitude of the second frictional force fluctuation. The amplitude of the second diagnostic signal changes. However, the method of changing the amplitude of each signal at this time is not necessarily the same as the method of changing the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal according to the above embodiment. This is because the variation period of the position deviation calculated by the control device 10 and the variation period of the feedback thrust input from the linear motor 2 to the control device 10 are not necessarily the same.

  13, 14 and 15 show changes in the amplitude (average value in a predetermined period) of each of the first diagnostic signal and the second diagnostic signal according to the change in the state of the motion guide apparatus 3 according to this modification. FIG. In FIG. 13, FIG. 14, and FIG. 15, the horizontal axis represents the number of days of use of the linear motor drive system 1, and the vertical axis represents the amplitude of the signal. In FIG. 13, FIG. 14 and FIG. 15, the solid line L1 shows the transition of the amplitude of the first diagnostic signal, and the alternate long and short dash line L2 shows the transition of the amplitude of the second diagnostic signal. Further, in FIGS. 13, 14, and 15, Fmax indicates a predetermined upper limit value, and Fmin indicates a predetermined lower limit value. The predetermined upper limit Fmax diagnoses that the state of the exercise guiding apparatus 3 is abnormal when at least one of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal exceeds the predetermined upper limit Fmax. It is preset as a value to be done. In addition, when at least one of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal falls below the predetermined lower limit Fmin, the predetermined lower limit Fmin is abnormal in the state of the motion guiding device 3 Is set in advance as a value to be diagnosed. Also in the case of this modification, different predetermined upper limit values and predetermined lower limit values may be set for each of the first diagnostic signal and the second diagnostic signal.

  FIG. 13 shows an example of the transition of the amplitude of each signal when flaking occurs on the rolling surface 31 a of the rail 31 in the motion guiding device 3. In this case, when the number of days of usage of the linear motor drive system 1 reaches D4, the amplitude (L1) of the first diagnostic signal reaches the predetermined upper limit Fmax. However, at this point in time, the amplitude (L2) of the second diagnostic signal is a value within the normal range (that is, the range between the predetermined lower limit Fmin and the predetermined upper limit Fmax). That is, in this case, as in the case shown in FIG. 8, it is considered that the first frictional force fluctuation is significantly changed more than the second frictional force fluctuation along with the flaking of the rolling surface 31 a of the rail 31. . Even in such a case, the state diagnosis of the motion guiding apparatus 3 by comparing the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with the predetermined lower limit Fmin and the predetermined upper limit Fmax. By performing the above, immediately after the number of days of use of the linear motor drive system 1 exceeds D4, it can be diagnosed that the state of the motion guide device 3 is abnormal.

  FIG. 14 shows an example of the transition of the amplitude of each signal when damage to the ball 34 occurs in the motion guide device 3. In this case, when the number of days of usage of the linear motor drive system 1 reaches D5, the amplitude (L2) of the second diagnostic signal reaches the predetermined upper limit Fmax. However, at this point in time, the amplitude (L1) of the first diagnostic signal is a value within the normal range. That is, in this case, as in the case shown in FIG. 9, it is considered that the second frictional force fluctuation is significantly changed more than the first frictional force fluctuation due to the damage of the ball 34 in the motion guiding device 3. Even in such a case, the state diagnosis of the motion guiding apparatus 3 by comparing the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with the predetermined lower limit Fmin and the predetermined upper limit Fmax. By performing the above, immediately after the number of days of use of the linear motor drive system 1 exceeds D5, it can be diagnosed that the state of the motion guide device 3 is abnormal.

FIG. 15 shows an example of the transition of the amplitude of each signal when preload loss occurs in the motion guide device 3. In this case, when the number of days of use of the linear motor drive system 1 reaches D6, the amplitude (L1) of the first diagnostic signal reaches the predetermined lower limit Fmin. However, at this time, the amplitude (L2) of the second diagnostic signal is a value within the normal range. That is, in this case, as in the case shown in FIG. 10, it is considered that the first frictional force fluctuation is significantly changed more than the second frictional force fluctuation along with the preload loss in the motion guide device 3. Even in such a case, the state diagnosis of the motion guiding apparatus 3 by comparing the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with the predetermined lower limit Fmin and the predetermined upper limit Fmax. By performing the above, immediately after the number of days of use of the linear motor drive system 1 exceeds D6, it can be diagnosed that the state of the motion guide device 3 is abnormal.

  As described above, also in the present modification, the state diagnosis of the motion guiding device 3 is performed by comparing each of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with a predetermined lower limit value and a predetermined upper limit value. By doing this, the state of the motion guide device 3 can be diagnosed with higher accuracy. Also in this modification, as shown in FIG. 13, FIG. 14, and FIG. 15, the state of the abnormal state of the motion guiding device 3, and the changes in the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal. If the correlation with the manner is determined in advance based on experiments etc., the aspect of the abnormal state of the motion guiding device 3 is estimated based on the change of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal. It is also possible (that is, to be able to estimate the cause of the change in friction force fluctuation).

  A ball screw can be used instead of the linear motor 2 as an actuator for moving the table 4. In such a configuration, the ball screw is controlled by the controller 10. At this time, the actual torque of the ball screw is fed back to the control device 10. Then, when the ball screw is driven, the fluctuation of the frictional force in the motion guide device 3 appears as the fluctuation of the torque fed back to the control device 10. Therefore, like the feedback thrust, the torque fed back to the control device 10 can be used as a predetermined diagnostic parameter in the state diagnosis of the motion guide device 3.

(Modification 2)
Hereinafter, a second modification of the state diagnosis of the motion guide device 3 performed by the diagnosis device 200 will be described. FIG. 16 is a diagram showing a schematic configuration of a linear motor drive system according to the present modification. In the present modification, an acceleration sensor 40 is installed on the table 4. The acceleration sensor 40 detects the acceleration of the table 4 when the table 4 is moved by driving the linear motor 2. Then, the detection value of the acceleration sensor 40 is input to the diagnostic device 200. The other configuration is the same as that shown in FIG. Since the block 32 of the motion guiding device 3 moves together with the table 4, the acceleration detected by the acceleration sensor 40 can be regarded as the acceleration of the block 32.

  When the linear motor 2 is driven, the acceleration of the table 4 when the table 4 is moved fluctuates according to the friction force fluctuation in the motion guide device 3. Therefore, the detection value of the acceleration sensor 40 is correlated with the frictional force fluctuation in the motion guiding device 3. So, in this modification, it replaces with a position deviation and uses a detection value of acceleration sensor 40 as a predetermined diagnostic parameter in state diagnosis of movement guidance device 3. FIG.

  In the present modification, the detection value of the acceleration sensor 40 is acquired by the parameter acquisition unit 210 of the diagnostic device 200 in association with the command value output to the linear motor 2. Then, in order to extract the first diagnostic signal and the second diagnostic signal from the signal related to the detection value of the acceleration sensor 40 acquired by the parameter acquisition unit 210, the signal processing unit 220 relates to the signal related to the detection value of the acceleration sensor 40. Process Also in this case, as in the above embodiment, the first diagnostic signal is a signal of a first predetermined frequency band, and the second diagnostic signal is a signal of a second predetermined frequency band. Thus, the first diagnostic signal can be extracted as a parameter correlated with the first frictional force fluctuation, and the second diagnostic signal can be extracted as a parameter correlated with the second frictional force fluctuation.

And also in the case of this modification, when the state of the motion guide device 3 changes, the amplitude of the first diagnostic signal and the amplitude of the first frictional force fluctuation change with the amplitude of the second frictional force fluctuation. The amplitude of the second diagnostic signal changes. Therefore, as in the first embodiment and the first modification, in the present modification, the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal are respectively compared with a predetermined lower limit value and a predetermined upper limit value. State diagnosis of the motion guide device 3 is performed. Thereby, the same effect as the state diagnosis of the motion guiding device 3 according to the first embodiment and the first modification can be obtained.

DESCRIPTION OF SYMBOLS 1 ... linear motor type drive system, 10 ... control device, 2 ... linear motor, 21 ... stator, 22 ... mover, 3 ... motion guide device, 31 ... Rails 32 blocks 31a rolling surfaces 33 circulation paths 34 balls 4 tables 40 acceleration sensors 5 linear scale 200 ... Diagnostic device, 210 ... Parameter acquisition unit, 220 ... Signal processing unit, 230 ... Diagnostic unit

Claims (6)

A plurality of rolling members are provided between a track member extending along a longitudinal direction and a moving member relatively movable along the longitudinal direction of the track member, the rolling surface being formed on the track member A moving member configured to be capable of rolling the movable body, engaged with the track member, and configured to circulate the plurality of rolling elements through a circulation passage formed therein; A condition diagnostic device for diagnosing the condition of the motion guide device,
A parameter acquisition unit for acquiring a predetermined diagnostic parameter correlated with a frictional force fluctuation generated when the moving member moves in the longitudinal direction of the track member in the motion guide device;
A signal processing unit that processes a signal related to the predetermined diagnostic parameter acquired by the parameter acquisition unit, wherein a first diagnostic signal that is a signal of a first predetermined frequency band from the signal related to the predetermined diagnostic parameter And a signal processing unit that extracts a second diagnostic signal that is a signal of a second predetermined frequency band lower than the first predetermined frequency band.
A diagnosis unit that diagnoses the state of the exercise guide apparatus based on the first diagnosis signal and the second diagnosis signal extracted by the signal processing unit;
The state diagnostic device of the movement guide device provided with   The first predetermined frequency band is a frequency band of friction force fluctuation caused by rolling of the rolling element on the rolling surface of the track member in the motion guide device, and the second predetermined frequency The band is a frequency band of the friction force fluctuation caused by the rolling element moving in and out between the rolling surface of the track member and the circulation path of the moving member in the movement guide device. The condition diagnostic apparatus of the exercise | movement guide apparatus of claim 1.   The diagnosis unit according to claim 1 or 2, wherein the diagnosis unit diagnoses the state of the exercise guiding apparatus by comparing each of the amplitude of the first diagnostic signal and the amplitude of the second diagnostic signal with a predetermined threshold. Condition diagnostic device for exercise guidance device. A control device for controlling an actuator when moving the moving member along the longitudinal direction of the track member, and a position at which position information on an actual position of the moving member on the track member is acquired by the motion guide device Further comprising an information acquisition device;
The predetermined diagnostic parameter is a difference between a command value regarding the position of the moving member output from the control device to the actuator and position information acquired by the position information acquiring device. The state diagnostic device of the movement guide device according to any one of the above. The motion guide device further includes a control device that controls an actuator when moving the moving member along the longitudinal direction of the track member,
The condition diagnosis apparatus for motion guidance apparatus according to any one of claims 1 to 3, wherein the predetermined diagnostic parameter is a thrust or a torque fed back from the actuator to the control apparatus. The motion guide device further includes an acceleration sensor that detects an acceleration when the moving member moves along the longitudinal direction of the track member,
The condition diagnosis apparatus of the motion guide apparatus according to any one of claims 1 to 3, wherein the predetermined diagnostic parameter is a detection value of the acceleration sensor.

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