JP2009144857A - Rolling bearing device with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing device with a sensor further accurately detecting a physical quantity to be detected by a sensor device, while reducing noise included in a signal. <P>SOLUTION: A intra-cap substrate 15 provided with a signal processing circuit 18 for processing the signal from the sensor device 10, is arranged inside a cap member 5 fixed to an outer ring 3 and sealing one end part in the axial direction of an inner shaft 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling bearing device with a sensor.

  Conventionally, as a rolling bearing device with a sensor, there is a rolling bearing device for a wheel described in JP 2007-127253 A (Patent Document 1).

  In this wheel rolling bearing device, inductance-type displacement sensors are arranged in two rows in the axial direction, and three translational loads and two moment loads of the wheel rolling bearing device are calculated.

  The signal from the displacement sensor is a signal that penetrates the cap member disposed so as to cover one end of the inner shaft 1 in the axial direction. The signal is output to the signal processing unit located on the opposite side, and the signal processing unit processes the signal.

In the background described above, it is desired to reduce noise included in signals in a rolling bearing device with a sensor.
JP 2007-127253 A

  Therefore, an object of the present invention is to provide a sensor-equipped rolling bearing device that can reduce noise contained in a signal and can more accurately detect a physical quantity to be detected by the sensor device.

In order to solve the above problems, a rolling bearing device with a sensor according to the present invention comprises:
A first track member having a track surface on the outer peripheral surface;
A second race member having a raceway surface on an inner peripheral surface;
A plurality of rolling elements disposed between the raceway surface of the first raceway member and the raceway surface of the second raceway member;
A cap member fixed to the second raceway member and sealing one end of the first raceway member in the axial direction;
A sensor device that outputs a signal based on at least one of a displacement of the first track member relative to the second track member and a relative rotational speed of the first track member relative to the second track member;
An in-cap substrate located inside the cap member;
And a signal processing circuit that receives the signal from the sensor device and processes the signal. The signal processing circuit is disposed on the in-cap substrate.

  The said 1st track member shall consist of a member which has a track surface in the said outer peripheral surface, and all the members fixed to this member so that a movement is impossible.

  According to the present invention, since the signal processing circuit is arranged on the in-cap substrate located in the cap, the length of the signal line connecting the sensor device and the signal processing circuit is remarkably shortened. it can. Therefore, it is difficult for noise to appear in the signal output from the sensor, and displacement and rotation speed can be detected more accurately.

  Further, since the cap member has a large surface area facing the outside and is excellent in heat dissipation, the amount of heat reaching the signal processing circuit existing inside the cap member is small. Therefore, it can suppress that the electronic component which comprises the said signal processing circuit deteriorates with a heat | fever.

  Further, according to the present invention, since the signal processing circuit is arranged on the in-cap substrate located in the cap member, the signal processing circuit is not deteriorated due to dust.

In one embodiment,
The sensor device is
An annular and plate-like coil arrangement substrate having a through hole through which the first track member passes;
A planar first coil arranged on the coil arrangement surface on one side of the coil arrangement substrate so as to surround the first track member over the entire circumference;
A planar second coil that is disposed on the coil placement surface and outputs the signal;
The portion of the coil placement surface that is surrounded by the second coil is located outward in the radial direction of the coil placement board with respect to the through hole.

  According to the above-described embodiment, the axial dimension of the sensor main body of the sensor device can be drastically reduced to approximately the thickness of the substrate, as described in a practical example described later. Therefore, the rolling bearing device with sensor can be made compact.

In one embodiment,
The sensor device includes a coil, and outputs a signal based on at least one of the displacement and the relative rotational speed based on a variation in inductance of the coil.

  According to the embodiment, the physical quantity to be detected can be detected more accurately using the highly reliable inductance type sensor device.

  According to the rolling bearing device with a sensor of the present invention, since the signal processing circuit is disposed on the in-cap substrate located in the cap, the length of the signal line connecting the sensor device and the signal processing circuit is greatly reduced. The noise included in the signal including physical information such as displacement information and rotation speed information can be reduced. Therefore, it is possible to detect the displacement and the rotational speed more accurately.

  Further, according to the rolling bearing device with a sensor of the present invention, the cap member has a large surface area facing the outside and is excellent in heat dissipation. Therefore, among the thermal forces conducted to the cap member, The amount of heat that reaches the signal processing circuit existing in is reduced. Therefore, it can suppress that the electronic component which comprises the said signal processing circuit deteriorates with a heat | fever.

  Further, according to the rolling bearing device with a sensor of the present invention, since the signal processing circuit is arranged on the in-cap substrate located in the cap member, the signal processing circuit may be deteriorated due to dust. Absent.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view in the axial direction of a vehicle rolling bearing device for a driven wheel (a hub unit for a driven wheel) which is a rolling bearing device with a sensor according to an embodiment of the present invention.

  This sensor-equipped rolling bearing device includes an inner shaft 1, an inner ring 2, an outer ring 3 as a second race member, a cap member 5, a plurality of balls 7 as an example of a rolling element, nuts 8, and a sensor device. 10.

  The sensor-equipped rolling bearing device includes an in-cap substrate 15 and a plurality of electronic components 17 mounted on the in-cap substrate 15 inside the cap member 5. The plurality of electronic components 17 constitute a signal processing circuit 18. The electronic component 17 is mounted on both surfaces of the in-cap substrate 15.

  The inner shaft 1 has a small diameter shaft portion 19, a medium diameter shaft portion 20, and a large diameter shaft portion 21. A screw is formed on the outer peripheral surface of the small diameter shaft portion 19. The medium-diameter shaft portion 20 is connected to the small-diameter shaft portion 19 via the step portion 30 and has an outer diameter larger than the outer diameter of the small-diameter shaft portion 19. The large-diameter shaft portion 21 is located on the opposite side of the medium-diameter shaft portion 20 from the small-diameter shaft portion 19 side. The large-diameter shaft portion 21 is connected to the medium-diameter shaft portion 20 via a step portion 22 and has an outer diameter larger than the outer diameter of the medium-diameter shaft portion 20. The outer circumferential surface of the large-diameter shaft portion 21 has an angular raceway groove as an outer raceway surface (not shown) on the right side of the paper. The outer diameter of the raceway groove increases as the distance from the middle-diameter shaft portion 20 increases. It has become.

  The inner shaft 1 has a brake disk mounting flange for mounting a brake disk at an end (on the right side of the drawing, not shown) on the large-diameter shaft portion 21 side in the axial direction.

  The inner ring 2 is fitted and fixed to the outer peripheral surface of the medium-diameter shaft portion 20 of the inner shaft 1. The end surface of the inner ring 2 on the large diameter shaft portion 21 side in the axial direction is in contact with the stepped portion 22. The inner ring 2 has an angular raceway groove 27 as an outer raceway surface on the outer diameter side of the large-diameter shaft portion 21. The outer diameter of the raceway groove 27 increases as the distance from the large diameter shaft portion 22 increases.

  The end surface of the inner ring 2 on the large diameter shaft portion 21 side in the axial direction is in contact with the step portion 22. The nut 8 is screwed into the screw of the small diameter shaft portion 19. The end surface of the inner ring 2 opposite to the large-diameter shaft portion 21 in the axial direction is in contact with the end surface of the nut 8 on the large-diameter shaft portion 21 side in the axial direction. The inner ring 2 is securely fixed to the inner shaft 1 by screwing the nut 8 into the large-diameter shaft portion 21 side in the axial direction for a predetermined distance.

  The outer ring 3 is located outward in the radial direction of the large-diameter shaft portion 21. The outer circumferential surface of the outer ring 3 includes an angular first raceway groove 28 as a first inner raceway surface and an angular second raceway groove as a second inner raceway surface (on the right side of the page). , Not shown). The plurality of balls 7 are arranged at intervals in the circumferential direction between the raceway groove 27 of the inner ring 2 and the first raceway groove 28 of the outer ring 3 while being held by a cage 29. . Although not shown, a plurality of balls other than the balls 7 are held by a cage between the track groove of the inner shaft 1 and the second track groove of the outer ring 3 on the right side of the page. Thus, they are arranged at intervals in the circumferential direction.

  The cap member 5 seals the end of the inner shaft 1 opposite to the wheel connection side in the axial direction. The cap member 5 includes an annular cored bar part 31 and a resin mold part 32. The core metal part 31 includes a large diameter cylindrical part 33, a small diameter cylindrical part 34, and a disk part 35, and the large diameter cylindrical part 33 is an inner peripheral surface of an end of the outer ring 3 opposite to the wheel connection side. In addition, it is fitted and fixed in a state having a tightening allowance. The small-diameter cylindrical portion 34 has an outer diameter smaller than the outer diameter of the large-diameter cylindrical portion 33 and continues to the large-diameter cylindrical portion 33 via a step portion. The small-diameter cylindrical portion 34 extends substantially in the axial direction. The disk portion 35 extends in a substantially radial direction from the end of the small diameter cylindrical portion 34 on the opposite side to the large diameter cylindrical portion 33 inward in the radial direction.

  The resin mold part 32 is located on the inner side in the radial direction from the small diameter cylindrical part 34 of the cored bar part 31 and on the inner shaft 1 side in the axial direction from the disk part 53 of the cored bar part 31. The resin mold portion 32 is formed along the inner peripheral surface 34 of the small-diameter cylindrical portion 34 of the core metal portion 31 and the end surface of the disc portion 35 on the inner shaft 1 side in the axial direction. Specifically, the resin mold portion 32 has a U-shaped cross section and includes a cylindrical portion 40 and a disc portion 41. The cylindrical portion 40 extends in a substantially axial direction, while the disc portion 41 extends in a substantially radial direction. The cylindrical portion 40 has an outer peripheral surface that comes into contact with the inner peripheral surface of the small-diameter cylindrical portion 34 of the core metal portion 31, while the disc portion 41 is on the end surface of the core metal portion 31 on the inner shaft 1 side in the axial direction. It has an axial end face that abuts.

  As described above, the in-cap substrate 15 is disposed inside the resin mold portion 32. The in-cap substrate 15 has a disk shape. The outer diameter of the cap inner substrate 15 is set to be approximately the same as the inner diameter of the inner peripheral surface of the small diameter cylindrical portion 34 of the core metal portion 31. The outer peripheral surface of the cap inner substrate 15 is in contact with the inner peripheral surface of the small diameter cylindrical portion 34 of the cored bar portion 31. The in-cap substrate 15 extends in a substantially radial direction.

  The sensor device 10 includes a sensor body 50 and a target member 51 made of a magnetic material. The sensor body 50 includes a coil placement board 70, a first coil 71, and a second coil 72.

  The coil arrangement substrate 70 is made of a glass cloth base epoxy resin. The coil arrangement substrate 70 is plate-like and annular and has a through hole 89, and the inner shaft 1 passes through the through hole 89.

  The outer peripheral surface of the coil arrangement substrate 70 is in contact with the inner peripheral surface of the large-diameter cylindrical portion 33 of the cored bar portion 31. The coil arrangement substrate 70 is fixed to the end surface of the resin mold portion 32 on the ball 7 side in the axial direction. The coil arrangement substrate 70 extends substantially in the radial direction of the outer ring 3. The first coil 71 is located radially inward of the second coil 72.

  The target member 51 has a substantially cylindrical shape. One end of the target member 51 in the axial direction is pressed into the end of the cylindrical outer peripheral surface of the inner ring 2 on the axial nut 8 side by press-fitting. One end portion of the target member 51 in the axial direction is fixed by being fitted onto a cylindrical outer peripheral surface 58 as one end portion of the outer peripheral surface of the inner ring 2 by an interference fit.

  In this specification, the first track member is composed of members having track surfaces on the outer periphery, that is, the inner shaft 1 and the inner ring 2 and all members fixed to the inner shaft 1 and the inner ring 2 so as not to move. Each of the inner shaft 1, the inner ring 2, and the target member 51 constitutes a part of the first track member.

  FIG. 2 is a schematic view schematically showing a peripheral portion of the coil arrangement substrate 70.

  As shown in FIG. 2, the target member 51 passes through the through hole 89 of the annular substrate 70. The first coil 71 has a planar shape, and is formed on one surface 75 of the substrate 70 so as to surround the target member 51 (first track member) over the entire circumference. On the other hand, the second coil 72 has a planar shape, and is formed in a spiral shape on the one surface 75 so as not to contact the first coil 71. The second coil 72 is disposed so as not to surround the first track member. The portion of the one surface 75 of the substrate 70 that is surrounded by the second coil 72 is located outside the through hole 89 of the substrate 70 in the radial direction of the substrate 70.

  There are four second coils 72, and the four second coils 72 are arranged at equal intervals in the circumferential direction. An oscillator 90 (drive circuit) is disposed on the in-cap substrate 15 (see FIG. 1). The oscillator 70 is connected to the first coil 71 via a cable 91.

  The oscillator 90 generates a high-frequency current from 100 KHz to 10 MHz, for example, and this high-frequency current flows into the first coil 71 via the cable 91.

  Since the target member 51 is made of a magnetic material, the magnetic flux generated by the first coil 71 passes through the target member 51. Therefore, when a load acts on the target member 51 and the target member 51 approaches a certain second coil 72, induction generated in the second coil 72 based on a high-frequency magnetic field generated by the first coil 71. While the electromotive force increases, when a load acts on the target member 51 and the target member 51 moves away from a certain second coil 72, the second coil 72 is applied to the second coil 72 based on the high-frequency magnetic field generated by the first coil 71. The induced electromotive force generated is reduced.

  Therefore, in the case where the target member 51 is formed of the same magnetic material as in this embodiment, if the induced electromotive force generated by each second coil 72 is measured, each second coil 72 and the target The distance to the member 51 can be measured.

  Further, for example, the portion of the target member that faces the first coil in the radial direction is formed of two portions (a first portion and a second portion) that are alternately positioned in the circumferential direction and have different magnetic permeability. Or when the irregularities are repeated in a gear shape in the circumferential direction, the induced electromotive force generated by the second coil is the relative rotational speed of the slinger with respect to the substrate (the second track member with respect to the first track member). The relative electromotive force of the second raceway member relative to the first raceway member can be detected by detecting the period.

  Returning to the description, each of the second coils 72 is connected to the signal processing circuit 18 of the in-cap substrate 15 via a signal line (not shown). The signal processing circuit 18 receives a signal (weak signal) from each second coil 72 and amplifies this signal with a known amplification circuit having an operational amplifier, or envelope detection with a known envelope detection circuit. For example, a signal in which the displacement information of the second track member relative to the first track member is remarkable is generated from the dielectric electromotive force generated in the second coil.

  According to the rolling bearing device with a sensor of the above embodiment, the signal processing circuit 18 is disposed on the in-cap substrate 15 located in the cap member 5, and therefore the signal processing circuit is on the rolling element side with respect to the cap member. Compared with the conventional configuration located on the opposite side, the length of the signal line connecting the sensor device 10 and the signal processing circuit 18 can be remarkably shortened. Therefore, it is difficult for noise to appear in the signal output from the sensor, and displacement and rotation speed can be detected more accurately. In particular, even if the signal from the sensor body 50 is a weak signal, the physical information can be surely picked up from the weak signal.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since the said cap member 5 has the large surface area which faces outside, and is excellent in heat dissipation, it reaches | attains the signal processing circuit 18 which exists in the inside of the cap member 5. The amount of heat to be reduced. Therefore, it is possible to suppress the electronic component 17 constituting the signal processing circuit 18 from being deteriorated by heat.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, the electronic which comprises the signal processing circuit 18 in the cap member 5 which exists in the position which receives the wind which generate | occur | produces when the ball 7 which is a rolling element rolls. Since the in-cap substrate 15 on which the component 17 is mounted is disposed, the heat dissipation effect of the cap member 5 can be further improved by the wind, and also for this reason, the deterioration of the electronic component 17 due to heat is suppressed. be able to.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since the said signal processing circuit 18 is arrange | positioned at the board | substrate 15 in a cap located in the cap member 5, deterioration of the electronic component 17 resulting from dust is carried out. It does not occur.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since the sensor main body 50 consists of the board | substrate 70 and the coils 71 and 72 formed in the one surface 75 of the board | substrate 60, the dimension of the axial direction of the sensor main body 50 is made. The thickness can be rapidly reduced to approximately the thickness of the substrate 70. Therefore, the sensor-equipped rolling bearing device can be made compact, and the arrangement space of the sensor-equipped rolling bearing device can be reduced.

  In addition, in the rolling bearing device with a sensor of the said embodiment, the four 2nd coils 72 existed, However, In this invention, the natural number other than 4 may exist for the 2nd coil.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the group of the coil which consists of two coils 71 and 72 was arrange | positioned at 1 row in the axial direction, in this invention, two coils as shown in FIG. By forming two sets of coils on both sides of the substrate, or by arranging a plurality of substrates in parallel and forming two sets of coils as shown in FIG. 3 on the surface of each substrate. 3 may be arranged in double rows in the axial direction.

  For example, two sets of coils as shown in FIG. 3 are arranged in two rows in the axial direction (the coil surrounding one set of first track members is the first coil, and the first coil is radially outward of the first coil). A second coil, a coil surrounding the first track member of the other set is a third coil, and a coil located radially outward of the third coil is a fourth coil), If a recess or a region having a different magnetic permeability from the periphery is formed on the outer peripheral surface of the first race member facing the second coil and the fourth coil in the radial direction, this acts on the rolling bearing device with sensor 5. It is possible to detect two loads (see Japanese Patent Application Laid-Open No. 2007-127253, the method of detecting five loads disclosed in this publication is completely different in this embodiment using the sensor body 50 having the substrate 70). Use similarly Door can be.).

  Further, in the rolling bearing device with a sensor according to the above embodiment, the sensor device 10 detects the displacement. However, in the present invention, the portion of the target member made of a magnetic material that faces the first coil in the radial direction It may be formed by two portions (first portion and second portion) that are alternately located in the direction and have different magnetic permeability, or may have a configuration in which unevenness is repeated in a gear shape in the circumferential direction. .

  In this case, the induced electromotive force generated by the second coil becomes an induced electromotive force having periodicity that depends on the relative rotation speed of the slinger with respect to the substrate (the relative rotation speed of the second track member with respect to the first track member). By detecting this period, the rotational speed of the second track member relative to the first track member can be detected.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the sensor apparatus 10 which has the sensor main body 50 which has the board | substrate 70 was used, in this invention, it has a coil as a sensor apparatus and the displacement of the inductance of a coil Based on the above, the displacement of the second track member relative to the first track member may be detected (see Japanese Patent Application Laid-Open No. 2007-127253). In this case, using a highly reliable inductance type sensor device, The physical quantity to be detected can be detected more accurately.

  Needless to say, the sensor device that can be used in the present invention is not limited to the sensor device using the substrate described in the above embodiment or the sensor device using the inductance type displacement sensor. That is, the sensor device that can be used in the present invention may be any displacement sensor as long as it is a non-contact type capable of detecting a gap, such as a sensor device using a Hall element.

  In the above embodiment, the sensor-equipped rolling bearing device is a hub unit. However, the sensor-equipped rolling bearing device is not limited to the hub unit, and any bearing device other than the hub unit such as a magnetic bearing device, for example. It may be. It is needless to say that the configuration of the present invention described in the above embodiment can be applied to various bearing devices having a need to measure a plurality of moment loads and translation loads.

  Moreover, in the rolling bearing with a sensor of the said embodiment, although the rolling element of the rolling bearing with a sensor manufactured was a ball, in this invention, even if the rolling element of the rolling bearing with a sensor manufactured is a roller, Needless to say, it may also contain rollers and balls.

It is sectional drawing of the axial direction of the rolling bearing device for vehicles for driven wheels (hub unit for driven wheels) which is a rolling bearing device with a sensor of one embodiment of the present invention. It is a schematic diagram which shows typically the peripheral part of the board | substrate for coil arrangement | positioning.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner shaft 2 Inner ring 3 Outer ring 5 Cap member 7 Ball 10 Sensor device 15 Inner cap board 18 Signal processing circuit 70 Coil arrangement board 71 First coil 72 Second coil 89 Through hole

Claims (3)

A first track member having a track surface on the outer peripheral surface;
A second race member having a raceway surface on an inner peripheral surface;
A plurality of rolling elements disposed between the raceway surface of the first raceway member and the raceway surface of the second raceway member;
A cap member fixed to the second raceway member and sealing one end of the first raceway member in the axial direction;
A sensor device that outputs a signal based on at least one of a displacement of the first track member relative to the second track member and a relative rotational speed of the first track member relative to the second track member;
An in-cap substrate located inside the cap member;
A sensor-equipped rolling bearing device, comprising: a signal processing circuit arranged on the in-cap substrate and receiving the signal from the sensor device and processing the signal. In the rolling bearing device with a sensor according to claim 1,
The sensor device is
An annular and plate-like coil arrangement substrate having a through hole through which the first track member passes;
A planar first coil arranged on the coil arrangement surface on one side of the coil arrangement substrate so as to surround the first track member over the entire circumference;
A planar second coil that is disposed on the coil placement surface and outputs the signal;
The rolling bearing device with a sensor is characterized in that a portion of the coil placement surface surrounded by the second coil is located on the outer side in the radial direction of the coil placement board with respect to the through hole. In the rolling bearing device with a sensor according to claim 1,
The sensor device includes a coil and outputs a signal based on at least one of the displacement and the relative rotational speed based on a variation in inductance of the coil.

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