JP2005037298A - Rolling device fitted with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling device fitted with a sensor for accurately detecting vibration created by the rolling device while keeping the accuracy of vibration detection from being lowered by the resonance of a printed circuit board even in the event that the printed circuit board mounted with a vibration detection element is fixed on a sensor enclosure in a bending direction. <P>SOLUTION: This rolling device 10 is fitted with a sensor for detecting the operating condition of the rolling device 17 by using a detector 20 equipped with a detection element comprising at least the vibration detection element 28, the printed circuit board 25 mounted with the detection element 28, and the sensor enclosure 21 mounted with the circuit board 25. In the rolling device 10, a surface of the circuit board 25 on the opposite side of a surface mounted with the detection element 28 is supported by a part 21d of the sensor enclosure. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rolling device with a sensor that detects an operating state of a rolling device such as a rolling bearing device or a linear motion device, and in particular, preventive maintenance of a mechanical device, for example, a railway vehicle used under a spring, The present invention relates to a rolling device with a sensor that can be applied to preventive maintenance of a bearing device of a moving body such as an automobile or a transport vehicle and to detect an abnormality of a bearing for an electric information device.

  In conventional rolling devices with a sensor, in order to detect abnormalities in the rolling device, such as bearing separation, at an early stage, a sensor that detects temperature, vibration, etc. is used to detect fluctuations in temperature, vibration, etc. associated with the abnormality. It was. In particular, a rolling device such as a bearing device for a railway vehicle often shows a remarkable variation in vibration when an abnormality occurs. For this reason, it is important to accurately detect abnormal vibration generated by the rolling device. Become.

  In the bearing diagnosis apparatus shown in FIG. 7, the output of the vibration measurement detector 101 provided in the bearing 100 is amplified by signal amplifiers 102 and 103 provided outside, and this is observed by the detection display device 104. Then, bearing diagnosis was performed (for example, refer to Patent Document 1). Further, as shown in FIG. 8, a detection element 110 that detects vibration, temperature, rotation speed, humidity, and the like and a detection circuit unit 111 are mounted on a printed circuit board 112, and the printed circuit board 112 is a part of the raceway ring 113. A sensor-equipped rolling bearing 114 attached to the part is known (for example, see Patent Document 2).

Further, a sensor-equipped bearing device in which a printed circuit board on which each detection element for detecting temperature, vibration, and rotation speed is mounted and an amplifier circuit is provided in a sensor holder and a bimorph piezoelectric element is used as the vibration detection element is known. (For example, refer to Patent Document 3). Further, there is known a rotation detection device provided with each detection element for detecting temperature, vibration, and rotation speed, and performing bearing abnormality determination by comparing with a threshold value and performing frequency analysis based on these detection signals (for example, , See Patent Documents 4 and 5.).
JP 2001-33353 A (page 2, FIG. 2) Japanese Patent Laid-Open No. 2002-206528 (page 2-3, FIG. 1) Japanese Patent Laying-Open No. 2003-65835 (page 3, FIG. 2) Japanese Patent Laid-Open No. 2002-340922 (pages 8-9 and 15-18) Japanese Patent Laid-Open No. 2002-295463 (pages 6-7 and 5-8)

  In Patent Documents 2 and 3, by providing each detection element on a printed circuit board, there is no need for an electric wire for connecting each detection element and various electronic elements, and the reliability of the sensor is improved without downsizing and problems such as aging and disconnection. However, the influence on the detection due to the natural frequency of the printed circuit board on which each detection element (in particular, the vibration detection element) is mounted has not been sufficiently considered.

  Generally, a printed circuit board on which a vibration detection element is mounted has a natural frequency, and if a detection signal includes a frequency component close to the natural frequency, they resonate. Also, when the printed circuit board and the vibration detection element are built in the sensor housing, the rigidity when the printed circuit board is fixed to the sensor housing in the bending direction (the direction in which the printed circuit board is allowed to bend in the plate thickness direction) is the tensile direction. Since it is smaller than the rigidity in the case of fixing in a direction that allows pulling from a direction parallel to the surface of the printed circuit board, the natural frequency in the bending direction of the printed circuit board is lower than the natural frequency in the pulling direction. The natural frequency in the pulling direction is several kHz (for example, 5 kHz, depending on the size of the printed circuit board) or more, but the natural frequency in the bending direction is often several kHz or less.

  When this natural frequency is equal to or higher than the frequency to be measured, it can be removed by passing through a low-pass filter (LPF), but when the natural frequency is close to the frequency to be measured, this natural frequency component Can not be removed. Therefore, when the printed circuit board is fixed to the sensor housing in the bending direction, there is a problem that it is difficult to remove the natural frequency component of the printed circuit board.

  The present invention has been made in view of the above circumstances. The purpose of the present invention is to improve the accuracy of vibration detection due to resonance of the printed circuit board even when the printed circuit board on which the vibration detecting element is mounted is fixed to the sensor housing in the bending direction. It is an object of the present invention to provide a sensor-equipped rolling device that can accurately detect vibration generated by the rolling device without lowering.

The object of the present invention is achieved by the following configurations.
(1) Operation of a rolling device using a detector including at least a detection element having a vibration detection element, a printed circuit board on which the vibration detection element is mounted, and a sensor housing to which the printed circuit board is attached In the rolling device with sensor for detecting a state, a surface opposite to the surface of the printed circuit board on which the vibration detecting element is mounted is supported by a part of the sensor casing. Moving device.
(2) The sensor-equipped rolling device according to (1), wherein the vibration detection element detects vibration in a direction perpendicular to the surface of the printed circuit board.
(3) The sensor-equipped rolling device according to (1) or (2), wherein the detection element further includes at least one of a speed detection element and a temperature detection element.
(4) The rolling device with a sensor according to any one of (1) to (3), wherein an amplification circuit for amplifying an output signal of the detection element is provided on the printed circuit board.
(5) The sensor casing is provided with a counterbore at a position facing the printed board, and electronic components are attached to both sides of the printed board (1) to (4). A rolling device with a sensor according to any one of the above.
(6) The rolling device with a sensor according to any one of (1) to (5), wherein the rolling device is a rolling bearing.
(7) The rolling device with a sensor according to any one of (1) to (5), wherein the rolling device is a ball screw.
(8) The rolling device with a sensor according to any one of (1) to (5), wherein the rolling device is a linear guide.
(9) The rolling device with a sensor according to any one of (1) to (5), wherein the rolling device is a linear ball bearing.
Here, the rolling bearing includes a so-called bearing device in which a housing is externally fitted to outer rings of a plurality of rolling bearings.

  In the rolling device with a sensor according to the present invention, the surface opposite to the surface of the printed circuit board on which the vibration detection element is mounted is supported by a part of the sensor housing. As a result, the natural frequency in the bending direction of the printed circuit board of the vibration detecting element can be increased and the amplitude of the vibration can be reduced, so that the vibration of the rolling device can be accurately measured.

Hereinafter, with reference to drawings, rolling device 10 with a sensor concerning a 1st embodiment of the present invention is explained in detail.
As shown in FIG. 1, a sensor-equipped bearing device 10 that is a sensor-equipped rolling device includes a pair of rolling bearings (here, ball bearings) 11 arranged at intervals in the axial direction, and each rolling bearing 11. A sensor unit 20 as a detector is attached to a rolling bearing device 17 having a housing 18 fitted on the outer ring 12 and a shaft 15 fitted on the inner ring 13 of each rolling bearing 11.

  A plurality of rolling elements (here, balls) 14 are disposed between the outer ring 12 and the inner ring 13. The rolling bearing device 17 according to this embodiment is a so-called inner ring rotating type in which the shaft 15 and the inner ring 13 rotate integrally, and the outer ring 12 and the housing 18 are stationary.

  The housing 18 is formed in a cylindrical shape, extends in an axial direction from one of the rolling bearings 11 (on the right side in the drawing), and an end cover 19 is fixed to the end thereof. The shaft 15 terminates in the housing 18 just before reaching the end cover 19. The sensor unit mounting portion of the housing 18 may be cylindrical or planar.

  As shown in FIG. 2, the sensor unit 20 includes a case main body 21 that is a sensor housing having a housing part that is open upward, and a detector case 23 that includes a case cover 22 that covers the open part of the case main body 21. The detector case 23 is fixed to the housing 18 via a plurality of bolts 24. The case main body 21 has a mounting portion 21a that is placed on the outer peripheral surface of the housing 18 without a gap, and a side portion 21b that stands from the side of the mounting portion 21a. Further, the mounting surface of the mounting portion 21 a (the surface fixed facing the outer peripheral surface of the housing 18) has a shape along the outer peripheral surface of the housing 18.

  The material of the case body 21 which is a sensor housing is arbitrary, but a sensor housing made of metal such as stainless steel or aluminum alloy is preferable in consideration of strength and the like. However, in order to prevent corrosion of the sensor housing, it is preferable to take measures such as using austenitic stainless steel such as SUS303 as the stainless steel, or anodizing the surface of the aluminum alloy. The shape of the case body 21 is not limited to the box shape, and may be other shapes such as a cylindrical shape.

  A printed circuit board 25 is fixed in the case main body 21, and electronic components including a detection element such as a vibration detection element (acceleration sensor) and a temperature detection element and a signal processing unit for processing a signal are interposed through the printed circuit board 25. And installed in a housing space surrounded by the attachment portion 21a and the side portion 21b. Further, a cable 26 for connecting these electronic components to an external measuring instrument is provided by being inserted through a cable outlet (not shown) formed in the case main body 21.

The mounting portion 21a is provided on the inner side of the side portion 21b, and has a substrate supporting portion 21d having a flush supporting surface 21c for fixing the printed circuit board 25, and a position facing the printed circuit board 25 at the position of the substrate supporting portion 21d. A counterbore 21e, which is a recess formed with a step on the inside, is formed.
As shown in FIG. 3, the printed circuit board 25 has a plurality of set screws 27 (four in this embodiment) arranged at the corners of the printed circuit board 25 so that the peripheral edge faces the substrate support 21d. ). The entire circumference of the printed board 25 is supported by the board support portion 21d, but it may be supported at both ends. Further, although the set screw 27 is used as a fixture for fixing the printed board 25 on the board support portion 21d, an adhesive or the like may be used.

A vibration detecting element 28 and a speed detecting element (rotational speed detecting element) 29 are mounted on one surface of the printed board 25 (the upper surface in the figure; the surface on the case cover 22 side). A temperature detection element 30 is mounted on the other surface of the printed circuit board 25 (the lower surface in the figure; the surface on the mounting plate 21a side), and the temperature detection element 30 is attached to a spot portion 21e formed on the mounting portion 21a. Be contained.
Note that either one of the speed detection element 29 and the temperature detection element 30 may be provided, and the attachment may be reversed or only on one surface. Moreover, you may provide another detection element in any surface as a detection element for monitoring the state of a bearing apparatus.

  Furthermore, on the printed circuit board 25, in addition to these detection elements, a low-pass filter (LPF) for attenuating and removing high-frequency components of the detection signal, an amplification circuit for amplifying the output signal of each detection element, Electronic components and the like constituting a signal processing unit such as an output circuit for outputting a detection signal as a voltage output or a current output (current loop output) are surface-mounted.

The vibration detecting element 28 includes a silicon acceleration sensor, a bimorph type vibration detecting element using a piezoelectric element, a vibration detecting element combining a piezoelectric element and a weight, a vibration detecting element having a cantilever structure, and the like. Instead of this, a vibration detecting element using a strain gauge is used. Silicon acceleration sensors are designed to reduce size, increase performance, and reduce costs by integrating silicon micromachine parts (mechanical elements) on the same silicon substrate as electronic circuits. Manufactured using manufacturing technology.
Further, the vibration detection element 28 may be a lead type vibration detection element instead of a surface mount type vibration detection element.

  The vibration detecting element 28 constantly detects vibration acting on the bearing device 17 and outputs a vibration signal (value), and supplies the vibration signal (value) to a signal processing unit mounted on the printed circuit board 25. The signal processing unit processes the vibration signal (value) given from the vibration detection element 28 and outputs it as a voltage signal or a current signal.

  A wiring (not shown) extending from the printed circuit board 25 is electrically connected to a cable 26 extending outside through a cable outlet (not shown) penetratingly formed in the case body 21 or the case cover 22. ing. The signal transmitted to the outside via the cable 26 may be a voltage output or a current output. In the case of current output, it is preferable to use current loop output because it is less susceptible to noise. In the case of current loop output, twisting the signal line and the power line of the cable 26 is more preferable because it is less susceptible to noise. In the case of voltage output, it is preferable to twist the signal line of the cable 26 because it is less susceptible to noise.

  As shown in FIG. 1, the vibration detection element 28 of the present embodiment is configured such that the vibration detection direction is a direction (plate thickness direction) perpendicular to the surface of the printed circuit board 25. In other words, the vibration detection element 28 is configured to be able to detect vibration in the direction indicated by the symbol V in the drawing (here, vibration in the radial direction orthogonal to the axis of the housing 18 and the shaft 15). Therefore, the vibration detection element 28 is attached to the printed circuit board 25 so that the vibration detection direction is the V direction, and the printed circuit board 25 is a sensor so that the plate thickness direction is the V direction, that is, the vibration detection direction. It is attached to the case main body 21 which is a housing.

  Then, as shown in FIG. 3, the vibration detecting element 28 is mounted on the peripheral portion of the printed circuit board 25 facing the support surface 21c of the substrate support section 21d between the set screws 27 for fixing the printed circuit board 25. Has been. That is, the surface opposite to the surface of the printed circuit board 25 on which the vibration detection element 28 is mounted is supported by the substrate support portion 21 d of the case body 21.

  As described above, according to the present embodiment, the surface opposite to the surface of the printed circuit board on which the vibration detection element 28 is mounted is supported by a part of the case body 21 that is a sensor housing. As a result, the natural frequency in the bending direction, that is, the thickness direction of the printed board can be increased and the amplitude of the vibration can be reduced in the portion of the printed board 25 on which the vibration detecting element 28 is mounted. Can be measured accurately. Further, the vibration detection direction of the vibration detection element 28 mounted on the printed board 25 is set to the plate thickness direction of the printed board 25. However, since the natural frequency in the plate thickness direction is increased, the printed board 25 is vibrated. Resonance can be prevented from occurring due to abnormal vibration detected by the detection element.

  Specifically, in the present embodiment, the natural frequency of the printed circuit board 25 to which the vibration detecting element 28 is attached is increased to a level equal to or higher than the natural frequency in the pulling direction and higher than the frequency band to be measured. can do. For this reason, even if the vibration component due to the resonance of the printed circuit board is superimposed, the superimposed component can be attenuated / removed using the low-pass filter, and does not affect the vibration measurement accuracy. Therefore, the vibration of the apparatus can be accurately measured.

In addition, the detector of the present embodiment includes not only the vibration detection element 28 but also the temperature detection element 30 to measure the temperature of the bearing device. Thereby, the sensor unit 20 can detect not only the abnormality by the vibration of the rolling device but also the abnormality by the temperature.
In addition, by providing the vibration detection element 28 and the temperature detection element 30 integrally on the same printed circuit board 25, the number of mounting steps can be reduced compared to the case where each sensor is individually mounted. Also, the mounting space can be reduced.

  Furthermore, since an amplifier circuit for amplifying the output signal of each detection element is mounted on the printed circuit board 25, it is not necessary to separately provide an amplifier outside the detector, thereby achieving compactness. Further, since the low-pass filter and the output circuit are mounted on the printed board in addition to the amplifier circuit, the assembly is completed simply by incorporating the printed board into the case body, and the number of assembling steps can be reduced.

  Further, the case body 21 is provided with a counterbore portion 21e on the lower side of the printed circuit board 25. By attaching electronic components to both surfaces of the printed circuit board 25, the space for mounting the printed circuit board can be reduced. As described above, since the back surface of the vibration detecting element 28 is supported by the portion of the printed circuit board 25 supported by a part of the case body, the portion of the printed circuit board 25 to which the vibration detecting element 28 is attached is supported. The natural frequency is increased, and the vibration detecting element 28 can avoid the influence of the rigidity reduction in the bending direction (plate thickness direction) due to the counterbore portion 21e.

In addition, in order to fix the printed circuit board 25 in the case body 21, a molding material such as an epoxy resin may be molded and fixed in the case body 21 in addition to using screws and an adhesive. Moreover, when it fixes with a screw, you may mold with an epoxy resin etc. after that. For waterproofing, soft silicone resin, silicone gel, or the like may be filled.
In the case of molding with a hard resin such as an epoxy resin, it is preferable that the detection element and the electronic component part are covered with a soft resin such as a silicon resin and then molded with a molding material. At this time, it is more preferable to mold with a molding material after covering foaming resin (foamable silicon resin etc.) on soft resin. By so doing, it is possible to prevent the detection element and the electronic component from being damaged by the pressure by relaxing the pressure generated by the difference in thermal expansion coefficient due to the temperature change.

  If the low-pass filter is unnecessary, the low-pass filter may be omitted. However, in order to remove the vibration of the natural frequency component of the printed circuit board 25 and the vibration detecting element 28, it is preferable to provide the low-pass filter.

  Next, the sensor-equipped rolling device 40 according to the second embodiment of the present invention will be described in detail. Note that in the second embodiment, members and the like having the same configurations and functions as those already described are denoted by the same or corresponding reference numerals in the drawing, and description thereof is simplified or omitted.

As shown in FIG. 4, in the rolling device with sensor 40 of the present embodiment, a protrusion 41 that protrudes from the case body 21 toward the printed circuit board 25 is provided at the center of the counterbore part 21 e of the case body 21. The upper surface 41a of the protrusion 41 faces the surface opposite to the surface of the printed circuit board 25 on which the vibration detecting element 28 is mounted.
The protrusion 41 is preferably configured to have the same height as the substrate support portion 21 d that supports the printed circuit board 25. However, when it is difficult to make the height of the protrusion 41 and the substrate support portion 21d completely the same, the height of the protrusion 41 is slightly lowered (several hundreds μm to several mm), so The gap is preferably filled with a rubber sheet or an insulating adhesive.

  Therefore, according to the present embodiment, the surface opposite to the surface of the printed circuit board 25 on which the vibration detection element 28 is mounted is supported by the protrusion 41 that is a part of the case body 21. As a result, as in the first embodiment, the natural frequency in the bending direction can be increased in the portion of the printed circuit board 25 on which the vibration detecting element 28 is mounted, and the amplitude of vibration can be reduced. Vibration can be measured accurately. In particular, in the second embodiment, when the detection element cannot be disposed between the set screws 27 as in the first embodiment, the protrusion 41 formed integrally with the case main body is centered on the counterbore 21e. The same operation can be obtained by providing the protrusion 41 to support the surface opposite to the surface of the printed circuit board 25 on which the vibration detecting element 28 is mounted.

  Next, the sensor-equipped rolling device 50 according to the third embodiment of the present invention will be described in detail. Note that in the third embodiment, members and the like having the same configurations and functions as those already described are denoted by the same or corresponding reference numerals in the drawing, and the description thereof is simplified or omitted.

  As shown in FIG. 5, in the rolling device with sensor 40 of the present embodiment, the support surface 21c of the substrate support portion 21d on the side where the vibration detection element 28 is provided is widened, and the vibration detection element 28 and the spot facing portion 21e Are inserted into the support surface 21c. Thereby, the vibration detection element 28 is mounted on the peripheral portion of the printed board 25 facing the support surface 21c of the board support portion 21d, and the two set screws 27 provided at the corner portion of the printed board 25 The two detection screws 51 provided between the vibration detection element 28 and the counterbore 21e are disposed so as to surround the periphery thereof.

  According to the present embodiment, the surface opposite to the surface of the printed circuit board 25 on which the vibration detection element 28 is mounted is supported by the support portion 21 d that is a part of the case body 21. As a result, as in the first embodiment, the natural frequency in the bending direction can be increased in the portion of the printed circuit board 25 on which the vibration detecting element 28 is mounted, and the amplitude of vibration can be reduced. Vibration can be measured accurately. Furthermore, in the third embodiment, since the vibration detection element 28 is arranged so that the periphery thereof is surrounded by the set screws 27 and 51, the rigidity of the periphery of the vibration detection element 28 is reinforced, and more accurate vibration is generated. Can be measured.

Further, the present invention is not limited to the embodiments described above, and appropriate modifications and improvements can be made.
In the above embodiment, the signal is extracted by the cable 26. However, the signal may be transmitted wirelessly using radio or the like. In the case of wireless, a sensor unit may be provided on the movable wheel side (on the movable member side).
Further, the rolling bearing in the bearing device 17 is not limited to a ball bearing, but may be a cylindrical roller bearing, a tapered roller bearing, or various double row bearings.

Furthermore, the present invention can be applied not only to the bearing device 17 but also to the ball screw 60 as shown in FIG. In the ball screw 60, by attaching the sensor unit (detector) 70 according to the present invention to the nut 61, it is possible to detect an abnormality such as separation at the engaging portion between the screw shaft 62 and the nut 61. The mounting partner of the sensor unit 70 is not limited to the nut 61 but may be attached to the support unit 63 on the fixed side that supports the screw shaft 62 or the support unit 64 on the simple support side. The screw shaft 62 is fixed in the axial direction to the support unit 63 on the fixed side by a lock nut 65, and is rotated by a drive motor 67 coupled via a coupling 66.
Further, not only the ball screw but also an abnormality such as peeling can be detected by attaching the sensor unit 70 to a movable part or rail in other linear motion parts such as a linear guide and a linear ball bearing.

  In the present embodiment, the vibration detection direction of the vibration detection element 28 is the radial direction orthogonal to the axes of the housing and the shaft. However, the present invention can also be applied to the case of detecting vibration in the axial direction of the housing and the shaft. In this case, the vibration detection element is attached to the printed circuit board so that the vibration detection direction is the axial direction, and the printed circuit board is attached to the case body so that the axial direction is the plate thickness direction.

It is a longitudinal section of a 1st embodiment of a rolling device with a sensor concerning the present invention. It is an enlarged view of the detector (sensor unit) in the rolling apparatus with a sensor shown in FIG. It is a principal part enlarged view of the detector of FIG. 2, (a) is the front view, (b) is sectional drawing which follows the III-III line of (a). It is a principal part enlarged view of the detector of the rolling apparatus with a sensor which concerns on 2nd Embodiment of this invention, (a) is the front view, (b) is sectional drawing which follows the IV-IV line of (a). It is. It is a principal part enlarged view of the detector of the rolling apparatus with a sensor which concerns on 3rd Embodiment of this invention, (a) is the front view, (b) is sectional drawing which follows the VV line of (a). It is. It is a side view which shows the example by which the detector of the rolling apparatus with a sensor which concerns on this invention was applied to the ball screw. It is a perspective view of the conventional rolling device with a sensor. It is sectional drawing of the other conventional rolling apparatus with a sensor.

Explanation of symbols

10 Bearing device with sensor (Rolling device with sensor)
DESCRIPTION OF SYMBOLS 11 Rolling bearing 12 Outer ring 13 Inner ring 15 Shaft 17 Rolling bearing apparatus (rolling apparatus)
20, 30, 40, 70 Sensor unit (detector)
21 Case body 22 Case cover 23 Detector case 25 Printed circuit board 26 Cable 27, 51 Set screw 28 Vibration detection element 29 Speed detection element 30 Temperature detection element 60 Ball screw

Claims (9)

  An operation state of the rolling device is detected using a detector including at least a detection element having a vibration detection element, a printed circuit board on which the vibration detection element is mounted, and a sensor housing to which the printed circuit board is attached. In the rolling device with a sensor, the surface of the printed circuit board on which the vibration detection element is mounted is supported by a part of the sensor casing.   The rolling device with a sensor according to claim 1, wherein the vibration detecting element detects vibration in a direction perpendicular to a surface of the printed circuit board.   The rolling device with a sensor according to claim 1, wherein the detection element further includes at least one of a speed detection element and a temperature detection element.   The rolling device with a sensor according to claim 1, wherein an amplification circuit for amplifying an output signal of the detection element is provided on the printed circuit board.   The said sensor housing | casing is provided with the counterbore part in the position facing the said printed circuit board, and the electronic component is attached to both surfaces of the said printed circuit board. Roller with sensor.   The rolling device with a sensor according to claim 1, wherein the rolling device is a rolling bearing.   The rolling device with a sensor according to any one of claims 1 to 5, wherein the rolling device is a ball screw.   The rolling device with a sensor according to claim 1, wherein the rolling device is a linear guide.   The rolling device with a sensor according to any one of claims 1 to 5, wherein the rolling device is a linear ball bearing.

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