JP2008275506A - Rolling bearing device with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing device with a sensor that has a sensor device capable of determining the moment load of a wheel and the axial translation load, and can detect the rotation speed of a rotation trajectory member even when an ABS sensor independent of the sensor device is not installed. <P>SOLUTION: An annular section 150 having a groove 155 extending axially is formed in a part of a displacement to be detected constituted by an outer peripheral surface of a target member 73. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling bearing device with a sensor having a race member, a rolling element and a sensor device, and more particularly to a hub unit having a displacement sensor.

  Conventionally, as a rolling bearing device with a sensor, there is a hub unit described in Japanese Patent Laid-Open No. 2001-21577 (Patent Document 1).

  The hub unit includes a rotating raceway, a fixed raceway, and one displacement sensor, and the displacement sensor is provided on the fixed raceway. Specifically, the outer peripheral surface of the fixed race has a hole extending in the radial direction, and the displacement sensor is inserted into the hole. The detection surface of the displacement sensor is directed to the outer peripheral surface of the rotating raceway.

  The displacement sensor described above is a gap between the rotating track ring and the fixed track ring that varies due to the displacement of the outer peripheral surface of the rotating track ring that occurs when a load is applied to the vehicle wheel (specifically, this gap corresponds to this gap). Electric signals that change). The hub unit calculates a vertical load acting on the wheel based on the gap detected by the displacement sensor.

  In the conventional rolling bearing device with a sensor, since there is one displacement sensor and the detection surface of the displacement sensor is directed to the outer peripheral surface of the rotating raceway, based on the detection value of the displacement sensor. While it is possible to determine the translational load acting on the wheels in the vertical direction, the vehicle's longitudinal moment load and the vehicle's vertical moment load generated due to the centrifugal force when the vehicle is turning, etc. In addition, there is a problem that it is impossible to obtain the translational load in the axial direction of the wheel.

Moreover, in the conventional rolling bearing device with a sensor, when it is desired to detect the rotational speed of the rotating raceway (wheel), a separate ABS sensor independent of the displacement sensor is required, and the rolling bearing device with the sensor is increased in size. There is a problem that the manufacturing cost of the rolling bearing device with sensor increases.
Japanese Patent Laid-Open No. 2001-21577 (see FIG. 8)

  Accordingly, an object of the present invention is to provide a sensor device that can determine the moment load of the wheel and the translational load in the axial direction, and the rotational speed of the rotary track member without installing an ABS sensor independent of the sensor device. It is an object of the present invention to provide a rolling bearing device with a sensor capable of detecting the above.

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 inner peripheral surface;
A second track member having a track surface and an annular displacement detector on the outer peripheral surface;
A rolling element disposed between the raceway surface of the first raceway member and the raceway surface of the second raceway member;
A sensor device for detecting a radial displacement of the displacement detection unit and an axial displacement of the displacement detection unit;
The displacement detection unit includes an annular part having a plurality of grooves extending in the axial direction and spaced from each other in the circumferential direction of the displacement detection unit,
The sensor device is
A first displacement detection unit having a detection surface opposed to the displacement detection unit in the radial direction;
A second displacement detector having a detection surface positioned in the first displacement detector at an interval in the axial direction and opposed to the displacement detector in the radial direction;
Based on the output of at least one of the first displacement detector and the second displacement detector, a signal associated with the relative rotation of the annular portion with respect to at least one of the first displacement detector and the second displacement detector. A rotation signal detector for detecting
A displacement signal detection unit that detects a signal accompanying the displacement of the displacement detection unit from the output of the first displacement detection unit and detects a signal accompanying the displacement of the displacement detection unit from the output of the second displacement detection unit It is characterized by having.

  According to the present invention, since the first displacement detection unit and the second displacement detection unit are separated from each other in the axial direction, the detection signal of the first displacement detection unit and the second displacement detection signal are included. Based on this detection signal, the translational load based on the axial translational displacement can be calculated, as well as the displacement variation due to the axial position of the sensor-equipped rolling bearing device. Based on this, the moment load acting on the sensor-equipped rolling bearing device can be calculated.

  Further, according to the present invention, the displacement detection unit has an annular portion that has a plurality of grooves that extend in the axial direction and are positioned at intervals in the circumferential direction of the displacement detection unit, And the said sensor apparatus detects the signal accompanying the relative rotation of the said annular part based on the output of at least one of the output of the said 1st displacement detection part, and a 2nd displacement detection part, A displacement signal detection unit that detects a signal accompanying the displacement of the displacement detection unit from the output of the first displacement detection unit and detects a signal accompanying the displacement of the displacement detection unit from the output of the second displacement detection unit Therefore, by detecting the groove of the annular part and the position of the hill that continues to the groove in the circumferential direction, a pulse signal associated with the relative rotational speed of the annular part can be obtained, and The relative rotational speed can be detected. That is, since the displacement detection unit for detecting the displacement forms an annular portion as a pulsed signal generation unit, the displacement detection unit can also be used for the rotational speed detection function, and the rolling bearing device with sensor Can be made compact, and the manufacturing cost of the rolling bearing device with sensor can be suppressed.

In one embodiment,
The displacement detection unit includes a first cylindrical surface portion connected to the annular portion via a step portion, and a step portion on the opposite side of the annular portion from the first cylindrical surface portion side, and the first cylinder. A second cylindrical surface portion located on the substantially same cylindrical surface as the surface portion,
Each groove extends in the axial direction from one end in the axial direction of the annular portion to the other end in the axial direction of the annular portion,
The first displacement detector and the second displacement detector are substantially overlapped when viewed from the axial direction,
The detection surface of the first displacement detection unit overlaps with the end portion of the first cylindrical surface portion on the annular portion side and the end portion of the annular portion on the first cylindrical surface portion side when viewed from the radial direction. On the other hand, the detection surface of the second displacement detection unit includes an end portion on the annular portion side of the second cylindrical surface portion and an end portion on the second cylindrical surface portion side of the annular portion as viewed from the radial direction. It overlaps with.

  According to the above embodiment, by detecting the axial position of the step portion between the annular portion and the first cylindrical portion and the axial position of the step portion between the annular portion and the second cylindrical portion, The axial translational displacement of the sensor-equipped rolling bearing device can be easily detected.

  Moreover, in one Embodiment, the surface of the said annular part has laminated | stacked the several steel plate in the said axial direction.

  According to the embodiment, the surface of the annular portion has a good magnetic property, a magnetic flux easily passes through, and an eddy current hardly occurs, that is, a structure in which a plurality of steel plates are laminated in the axial direction. Therefore, it is possible to reduce the loss of the electric signal due to the generation of eddy current, and to increase the sensitivity of the sensor.

In one embodiment,
The plurality of grooves have substantially the same width, are arranged at equal intervals in the circumferential direction,
The first displacement detection unit and the second displacement detection unit substantially overlap each other when viewed from the axial direction, and each of the first displacement detection unit and the second displacement detection unit is equally spaced in the circumferential direction. It consists of four arranged displacement sensors,
In the radial cross section passing through the annular portion and the first displacement detector,
Of the plurality of grooves, the two grooves adjacent in the circumferential direction are defined as a first groove and a second groove,
A hill located between the first groove and the second groove is an intermediate hill,
A straight line passing through the middle point of the intermediate hill and the center of the annular portion is a hill center passing straight line,
A straight line passing through one end of the first groove in the circumferential direction parallel to the hill center passing straight line, and a straight line passing through the other end in the circumferential direction of the first groove parallel to the hill center passing straight line A distance is A [mm],
A distance between a straight line parallel to the hill center passing straight line and passing through one end of the intermediate hill in the circumferential direction and a straight line parallel to the hill center passing straight line and passing through the other end in the circumferential direction of the intermediate hill Is B [mm],
When 1/4 of the length of the detection surface of the first displacement detector is C [mm],
A <B, C <A + B, and B <C.

  According to the embodiment, since A <B, groove processing can be easily performed on the annular portion. Further, since C <A + B, the resolution of the pulse signal can be increased. Further, since B <C, the rotational speed of the relative rotation in a short time can be calculated.

In one embodiment,
The second track member has a rotor mounting flange for mounting the rotor, and the first track member has a vehicle body mounting flange for mounting the vehicle body,
The plurality of grooves are arranged at equal intervals in the circumferential direction,
The first displacement detection unit and the second displacement detection unit substantially overlap each other when viewed from the axial direction, and each of the first displacement detection unit and the second displacement detection unit is equally spaced in the circumferential direction. It consists of four arranged displacement sensors,
The displacement signal detection unit detects a signal associated with the displacement of the displacement detection unit from the signal output by each displacement sensor in each displacement sensor,
The sensor device receives a signal from the displacement signal detection unit and detects the displacement of the displacement detection unit of the displacement sensor of the first displacement detection unit in each of the displacement sensors of the first displacement detection unit. Calculating the difference between the accompanying signal and the signal accompanying the displacement of the displacement detection part of the displacement sensor of the second displacement detection part of the second displacement detection part substantially overlapping the axial direction of the displacement sensor of the first displacement detection part; There is a moment load calculating section for calculating a plurality of moment loads acting on the wheel based on this difference.

  According to the embodiment, the moment load acting on the wheel can be calculated by the moment load calculation unit. Therefore, the rotational speed of the wheel and the moment load acting on the wheel can be calculated, and the operation control during the traveling of the vehicle can be accurately performed based on the information.

  Further, according to the embodiment, the moment load calculation unit accompanies the displacement of the displacement detection unit of the displacement sensor of the first displacement detection unit in each of the displacement sensors of the first displacement detection unit. The difference between the signal and the signal associated with the displacement of the displacement detection portion of the displacement sensor of the second displacement detection portion of the second displacement detection portion, which substantially overlaps the axial direction of the displacement sensor of the first displacement detection portion, is calculated. Since the moment load acting on the wheel is calculated based on the difference, the detection sensitivity of the displacement in the direction of detection can be approximately doubled, and the temperature drift in the direction of detection can be increased. Noise can be removed.

  According to the rolling bearing device with a sensor of the present invention, the first displacement detection unit and the second displacement detection unit, which are separated from each other in the axial direction, have the detection signal of the first displacement detection unit. Based on the signal with the second displacement detection signal, the translational displacement in the axial direction can be calculated as well as the variation of the displacement due to the axial position of the sensor-equipped rolling bearing device. Based on the fluctuation, the moment load acting on the sensor-equipped rolling bearing device can be calculated.

  In addition, according to the rolling bearing device with a sensor of the present invention, the pulse signal associated with the relative rotation of the annular portion is obtained by detecting the groove of the annular portion in the detected displacement portion and the position of the hill that continues to the groove in the circumferential direction. And the rotational speed of the relative rotation of the annular portion can be detected. That is, the displacement detection unit that detects the displacement can also serve as a pulsed signal generation unit, and the displacement detection unit can detect the rotation speed of the annular portion. Therefore, it is not necessary to separately provide an independent ABS sensor in the displacement detection unit, so that the sensor-equipped rolling bearing device can be made compact and the manufacturing cost of the sensor-equipped rolling bearing device can be suppressed.

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

  FIG. 1 is an axial sectional view of a hub unit which is an embodiment of a rolling bearing device with a sensor according to the present invention.

  This hub unit includes an inner shaft 1, an inner ring 2, an outer ring 3 as a first race member, a plurality of first balls 4 as rolling elements, a plurality of second balls 5 as rolling elements, a case member 6, and The sensor device 10 is provided.

  The inner shaft 1 has a small-diameter shaft portion 19, a medium-diameter shaft portion 20, and a large-diameter shaft portion 21 as a second shaft portion. 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 18 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 peripheral surface of the large-diameter shaft portion 21 has an angular type raceway groove 23 as a raceway surface, and the outer diameter of the raceway groove 23 increases as the distance from the medium-diameter shaft portion 20 increases.

  The inner shaft 1 has a center hole 31. The center hole 31 is formed in the central portion in the radial direction of the end surface of the inner shaft 1 on the large diameter shaft portion 21 side in the axial direction. The first center hole 31 has a cylindrical portion and extends a predetermined distance in the axial direction. The inner shaft 1 has a rotor mounting flange (or a wheel mounting flange) for mounting a rotor (or a wheel) (not shown) at the end of the large-diameter shaft portion 21 in the axial direction. 50.

  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 type raceway groove 28 as a raceway surface on the large-diameter shaft portion 21 side of the outer peripheral surface thereof. The outer diameter of the raceway groove 28 increases as the distance from the large-diameter shaft portion 21 increases. The outer peripheral surface of the inner ring 2 has a cylindrical outer peripheral surface 26 on the side opposite to the large-diameter shaft portion 21 side in the axial direction. The cylindrical outer peripheral surface 26 is different from the large-diameter shaft portion 21 side of the raceway groove 28. The track shoulder 29 located on the opposite side is connected via a step 30. The track shoulder 29 has a cylindrical outer peripheral surface 35. The outer diameter of the cylindrical outer peripheral surface 26 located at the axial end of the outer peripheral surface of the inner ring 2 is smaller than the outer diameter of the cylindrical outer peripheral surface 35 of the track shoulder 29.

  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. As shown in FIG. 1, the nut 63 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 63 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 63 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 inner peripheral surface of the outer ring 3 has an angular first raceway groove 44 as a raceway surface and an angular second raceway groove 45 as a raceway surface. The outer ring 3 has a body mounting flange 75 for fixing to the vehicle body. The plurality of first balls 4 are spaced apart from each other in the circumferential direction while being held by the first cage 40 between the raceway groove 28 of the inner ring 2 and the first raceway groove 44 of the outer ring 3. The plurality of second balls 5 are held by the second cage 41 between the raceway groove 23 of the inner shaft 1 and the second raceway groove 45 of the outer ring 3, They are arranged at intervals in the circumferential direction.

  The case member 6 includes a cylindrical member 52 and a disk-shaped lid member 53. An end of the inner peripheral surface of the cylindrical member 52 on the outer ring 3 side is fixed to an end of the outer peripheral surface of the outer ring 3 on the small diameter shaft portion 19 side by a set screw 55. On the other hand, the lid member 53 closes the opening of the cylindrical member 52 on the side opposite to the outer ring side. In this way, foreign matter is prevented from entering the inside of the sensor-equipped rolling bearing device.

  The sensor device 10 includes a first displacement detector 70, a second displacement detector 71, and a target member 73. The first and second displacement detectors 70 and 71 are fixed to the inner peripheral surface of the cylindrical member 52. On the other hand, the target member 73 has a cylindrical shape. One end of the target member 73 in the axial direction is pressed into the cylindrical outer peripheral surface 26 of the inner ring 2 by press-fitting. In other words, the one end portion of the target member 73 is externally fitted and fixed to the cylindrical outer peripheral surface 26 as one end portion of the outer peripheral surface of the inner ring 2. The inner shaft 1, the inner ring 2 and the target member 73 constitute a second track member, while the outer peripheral surface of the target member 73 is a displacement detection unit.

  FIG. 2 is an enlarged cross-sectional view of the periphery of the first displacement detector 70 in FIG.

  As shown in FIG. 2, the second displacement detector 71 is located on the wheel side (the rotor mounting flange 50 side) relative to the first displacement detector 70. Each of the first and second displacement detectors 70 and 71 is fixed to the inner peripheral surface of the cylindrical member 52. The first displacement detection unit 70 is the same as the second displacement detection unit 71, and the first displacement detection unit 70 is disposed at an interval in the axial direction with respect to the second sensor 71. The entire first displacement detector 70 overlaps the second displacement detector 71 substantially in the axial direction.

  The first displacement detector 70 has a sensor ring 83 (see FIG. 1) and four displacement sensors 84, while the second displacement detector 71 has a sensor ring 93 (see FIG. 1) and four displacements. Sensor 94. As shown in FIG. 1, the sensor ring 83 and the sensor ring 93 are fixed to the flange portion 57 of the cylindrical member 52 with a set screw 59 with an annular spacer 58 interposed. Each displacement sensor 84 extends radially inward from the inner peripheral surface of the sensor ring 83, while each displacement sensor 94 extends radially inward from the inner peripheral surface of the sensor ring 93. ing.

  The first displacement detector 70 and the second displacement detector 71 can be fixed to the case member 6. Therefore, after fixing the first displacement detection unit 70 and the second displacement detection unit 71 to the case member 6, the first and second displacement detectors can be simply fixed to the outer peripheral surface of the outer ring 3 as described above. The two displacement detectors 70 and 71 can be easily fixed to the hub unit. That is, it is not necessary to attach the displacement detectors 70 and 71 to the outer ring 3 individually, and it is not necessary to provide the outer ring 3 with a mounting structure such as a through hole for mounting the displacement detectors 70 and 71. In addition, since the relative positions of the displacement detectors 70 and 71 with respect to the case member 6 are determined in advance, the displacement detectors 70 and 71 can be accurately and easily positioned with respect to the target member 73.

  FIG. 3 is a diagram illustrating the relationship between the relative positions of the first displacement detection unit 70 and the second displacement detection unit 71 and the target member 73 and the structure of the outer peripheral surface of the target member 73.

  The outer peripheral surface of the target member 73 has an annular portion 150, a first cylindrical surface portion 151, and a second cylindrical surface portion 152. The annular portion 150, the first cylindrical surface portion 151, and the second cylindrical surface portion 152 have the same central axis. The first cylindrical surface portion 151 is located on one side in the axial direction of the annular portion 150, while the second cylindrical surface portion 152 is located on the other side in the axial direction of the annular portion 150. The first cylindrical surface portion 151 is connected to the annular portion 150 via a step portion 156, while the second cylindrical surface portion 152 is connected to the annular portion 150 via a step portion 157. The first cylindrical surface portion 151 and the second cylindrical surface portion 152 are located on substantially the same cylindrical surface.

  The annular portion 150 has a plurality of identical grooves 155. The number of grooves 155 may be any number as long as it is plural. For example, 96 can be adopted as the number of grooves 155. Each of the plurality of grooves 155 extends in the axial direction from one axial end of the annular portion 150 to the other axial end of the annular portion 150. The plurality of grooves 155 are arranged at equal intervals in the circumferential direction of the annular portion 150. The bottom of the groove 155 of the annular portion 150 has a cylindrical surface, and the outer diameter of the bottom of the groove 155 of the annular portion 150 is larger than the outer diameter of the first and second cylindrical surface portions 151 and 152.

  In the state where the target member 73 is not displaced, the radially inner end surface of the first displacement detector 70 is the end portion of the first cylindrical surface portion 151 on the annular portion 150 side and the first cylindrical surface portion of the annular portion 150. The radial inner end surface of the second displacement detector 71 is overlapped with the end portion on the annular portion 150 side of the second cylindrical surface portion 152 and the second end portion of the annular portion 150. It overlaps with the end portion on the cylindrical surface portion 152 side in the radial direction. Referring to FIG. 2 again, the outer peripheral surface of the target member 73 has a first annular groove 134 and a second annular groove 135. The first cylindrical surface portion 151 corresponds to the bottom surface of the first annular groove 134, while the second cylindrical surface portion 152 corresponds to the bottom surface of the first annular groove 134.

  FIG. 4 is a diagram illustrating the surface of the annular portion 150 in detail.

  As shown in FIG. 4, the surface of the annular portion 150 is composed of a silicon steel plate 200 as an example of a steel plate. Specifically, the annular portion 150 is formed by laminating a plurality of silicon steel plates 200 in the axial direction.

  FIG. 5 is a cross-sectional view in the radial direction passing through the annular portion 150 and the first displacement detector 70, and is a diagram for explaining the arrangement configuration of the displacement sensor 84 in the circumferential direction. Although not described, the displacement sensor 94 also has the same circumferential arrangement as the displacement sensor 84. The description of the structure and subscripts of the displacement sensor 94 will be omitted in the following description of the structure and subscripts of the displacement sensor 84.

  The four displacement sensors 84 are arranged at equal intervals in the circumferential direction of the inner shaft 1. Specifically, the displacement sensor 84 is located at a position that is radially opposite to a portion of the target member 73 that is located at the most vertically upper position and at a position that is most vertically below the target member 73 in a state where the hub unit is installed at a predetermined position. A position facing the position in the radial direction, a position in the target member 73, a position in the radial direction facing the frontmost position of the vehicle to which the hub unit is attached, and the hub unit in the target member 73. It is installed in the position which opposes the radial direction at the position of the backmost side of the vehicle which is attached.

  Hereinafter, in the state where the hub unit is installed at a predetermined position, a sensor 84 that is installed at a position that is radially opposite to a portion that is located at the uppermost vertical position of the target member 73 is referred to as a sensor 84t. A sensor 84 installed at a position radially opposite to the most vertically lower portion of the sensor is referred to as a sensor 84b, and the target member 73 has a diameter at a position on the most front side of the vehicle to which the hub unit is attached. The sensor 84 installed at a position facing the direction is referred to as a sensor 84f, and the target member 73 is installed at a position facing the rearmost position of the vehicle to which the hub unit is attached in the radial direction. The sensor 84 is referred to as a sensor 84r.

  As shown in FIG. 5, the displacement sensor 84t has a magnetic pole 99t and a coil 100t, the displacement sensor 84b has a magnetic pole 99b and a coil 100b, and the displacement sensor 84f has a magnetic pole 99f and a coil 100f. The displacement sensor 84r has a magnetic pole 99r and a coil 100r.

  Each of the magnetic poles 99t, 99b, 99f, and 99r is connected to the inner peripheral surface of the sensor ring 83 and extends in the radial direction. The coil 100t is wound around the magnetic pole 99t, the coil 100b is wound around the magnetic pole 99b, the coil 100f is wound around the magnetic pole 99f, and the coil 100r is wound around the magnetic pole 99r. Yes.

  The radially inner end surfaces of the magnetic poles 99t, 99b, 99f, and 99r are opposed to the outer peripheral surface of the target member 71 in the radial direction via a gap. The inner end surfaces in the radial direction of the magnetic poles 99t, 99b, 99f, and 99r are detection surfaces of the displacement sensors 84t, 84b, 84f, and 84r. The detection surface of the first displacement detector 70 includes a radially inner end face of the magnetic pole 99t, a radially inner end face of the magnetic pole 99b, a radially inner end face of the magnetic pole 99f, and a diameter of the magnetic pole 99r. It is composed of the inner end face of the direction. The first displacement detector 70 and the second displacement detector 71 have a total of eight displacement sensors 84t, 84b, 84f, 84r, 94t, 94b, 94f, and 94r. The eight displacement sensors 84t, 84b, 84f, 84r, 94t, 94b, 94f, 94r are the same.

  In the cross-sectional view of FIG. 5, among the plurality of grooves 155, two grooves 155 adjacent in the circumferential direction are defined as a first groove 190 and a second groove 191, and the first groove 190 and the second groove 191 are interposed between them. The hill located is defined as an intermediate hill 192, and a straight line passing through the midpoint 193 in the circumferential direction of the intermediate hill 192 and the center 194 of the annular portion 150 is defined as a straight line passing through the hill center. The distance between a straight line passing through one end of the circumferential direction of one groove 190 and the straight line passing through the other end in the circumferential direction of the first groove 190 is A [mm] The distance between a straight line parallel to the center passing straight line and passing through one end in the circumferential direction of the intermediate hill 192 and a straight line passing through the other end in the circumferential direction of the intermediate hill 192 and parallel to the hill center passing straight line is B [mm. And ¼ of the length of the detection surface of the first displacement detector 70, that is, each When the length of the radially inner end face of the magnetic poles 99t, 99b, 99f, 99r of the position sensors 84t, 84b, 84f, 84r is C [mm], A <B, C <A + B, and B < C is established.

  FIG. 6 is a diagram illustrating an example of a gap detection circuit connected to the second displacement detector 71. Although not described, the same displacement detection circuit as that connected to the second displacement detector 71 is also connected to the first displacement detector 70.

  As shown in FIG. 6, each of the two displacement sensors 94 t and 94 b positioned in the vertical direction is connected to the oscillator 130. An alternating current having a constant period is supplied from the oscillator 130 to the displacement sensors 94t and 94b. A synchronization capacitor 131 is connected in parallel to each of the displacement sensors 94t and 94b.

  Then, the value of the saturation line of the output voltage of the displacement sensor 94t and the displacement sensor 94b (hereinafter, in each displacement sensor, the value of the saturation line of the output voltage of the displacement sensor described in detail below is referred to as a displacement detection value). ) Is input to the differential amplifier 132 to obtain an output voltage (displacement detection value) corresponding to the vertical direction, thereby removing temperature drift noise and the sensitivity of the displacement signal in the vertical direction by differential amplification. Is improved approximately twice. Although explanation is omitted, the two displacement sensors 94f and 94r positioned in the front-rear direction also remove noise due to temperature drift by taking the difference with the differential amplifier in the same manner as described above, and the displacement signal in the front-rear direction. The sensitivity is improved approximately twice.

In each of the displacement sensors 84t, 84b, 84f, 84r, 94t, 94b, 94f, 94r, the inductance is L, the area of the detection surface of the displacement sensor is A, the magnetic permeability is μ, the number of turns of the coil is N, the displacement sensor When the distance (gap) from the detection surface to the target member 73 is d, the following equation (a) is established.
L = A × μ × N ² / d (a)

  When the gap d to the target member 73 changes, the inductance L of the displacement sensors 84t, 84b, 84f, 84r, 94t, 94b, 94f, 94r changes and the output voltage changes. Therefore, a radial gap from the detection surface of the displacement sensor 24 to the target unit 4 is detected by detecting the fluctuation of the output voltage.

  FIG. 7 is a diagram showing a positional relationship among the detection surface A1 of the displacement sensor 84t, the detection surface A2 of the displacement sensor 94t, the first annular groove 134, and the second annular groove 135.

  Although not described, the positional relationship between the detection surface of the displacement sensor 84b, the detection surface of the displacement sensor 94b, the first annular groove 134 and the second annular groove 135 is as follows: the detection surface A1 of the displacement sensor 84t and the detection surface of the displacement sensor 94t. The positional relationship between A2, the first annular groove 134 and the second annular groove 135 is the same. The positional relationship between the detection surface of the displacement sensor 84f, the detection surface of the displacement sensor 94f, the first annular groove 134 and the second annular groove 135 is as follows: the detection surface A1 of the displacement sensor 84t, the detection surface A2 of the displacement sensor 94t, and the first. The positional relationship between the annular groove 134 and the second annular groove 135 is the same. The positional relationship between the detection surface of the displacement sensor 84r, the detection surface of the displacement sensor 94r, the first annular groove 134 and the second annular groove 135 is as follows: the detection surface A1 of the displacement sensor 84t, the detection surface A2 of the displacement sensor 94t, The positional relationship between the annular groove 134 and the second annular groove 135 is the same.

  As shown in FIG. 7, in the axial direction, the central portion of the detection surface A1 substantially coincides with the edge of the first annular groove 134 on the second annular groove 135 side, while the central portion of the detection surface A2 is The two annular grooves 135 substantially coincide with the edge on the first annular groove 134 side.

  If the target member 73 is displaced from the state in the axial direction toward the lid member 53 by a distance δ, the lap length in the axial direction between the detection surface A1 and the first annular groove 134 (the length overlapping in the axial direction). Decreases, the wrap length in the axial direction between the detection surface A2 and the second annular groove 135 (the overlapping length in the axial direction) increases. From this, the displacement detection value of the gap of the displacement sensor 84 decreases, while the displacement detection value of the gap of the displacement sensor 94 increases. Thus, when the target member 73 is displaced in the axial direction, a difference is generated between the displacement detection value detected by the displacement sensor 84t and the displacement detection value detected by the displacement sensor 94t.

  The first annular groove 134 and the second annular portion 135 are arranged so that the displacement detection values detected by the displacement sensor 84t and the displacement sensor 94t change in the positive and negative directions when the target member 73 moves in the axial direction. The axial position with respect to 84t and 94t is set. By taking the difference between the displacement detection value of the displacement sensor 84t and the displacement detection value of the displacement sensor 94t, the axial translation amount of the inner ring 2 (inner shaft 1) (the axial displacement, which has a correlation with the translation load). ) Is detected.

  Displacement detection values of displacement sensors 84t, 84b, 84f, 84r on the vehicle center side (hereinafter referred to as inner side) and displacement detection values of displacement sensors 94t, 94b, 94f, 94r on wheel side (hereinafter referred to as outer side). The displacement detection value for the unit translation amount in the axial direction of the second track member is amplified by taking the difference (the difference in the displacement detection values of the displacement sensors having the same subscript). Therefore, the detection sensitivity of the displacement can be increased.

  Contrary to the arrangement shown in FIG. 7, the inner annular groove on the inner side is shifted to the outer side with respect to the detection surface of the first displacement detector, and the second annular groove on the outer side is detected as the second displacement. In this case, the same effects as described above can be obtained.

  FIG. 8 is a diagram illustrating a connection structure between the displacement detection units 70 and 71 and the signal processing unit 140 located on the opposite side of the lid member 53 from the displacement detection units 70 and 71.

  The sensor device 10 includes a signal processing unit 140, and each displacement sensor 84 t, 84 b, 84 f, 84 r, 94 t, 94 b, 94 f, 94 r is connected via a signal line 36 that penetrates the lid member 53 of the case member 6. It is connected to the signal processing unit 140. The output voltage (displacement detection value) obtained from each displacement sensor 84t, 84b, 84f, 84r, 94t, 94b, 94f, 94r is calculated by the signal processing unit 140 by the calculation method described below, thereby acting on the wheels. The moment load and translational load in each direction are calculated.

  FIG. 9 is a diagram for explaining directions used in the present embodiment, and FIGS. 10A and 10B are diagrams for explaining definitions of sensor displacement detection values used in the present embodiment. FIG. 10A is a diagram of the displacement sensor as viewed from the outside in the radial direction, and FIG. 10B is a diagram of the displacement sensor as viewed from the axial direction.

  As shown in FIG. 9, in this embodiment, the front-rear horizontal direction of the wheel is defined as the x-axis direction, the left-right horizontal direction (axial direction) of the wheel is defined as the y-axis direction, and the vertical direction of the wheel is defined as the z-axis direction.

  Further, as shown in FIG. 10A, the subscript “i” is used as the displacement detection value of the inner side displacement sensors 84t, 84b, 84f, 84r, and is attached to the outer side displacement sensors 94t, 94b, 94f, 94r. Use the letter “o”. Further, as already described above, the displacement detection value of the front sensor is defined as “f (front)”, the displacement detection value of the rear sensor is defined as “r (rear)”, and The displacement detection value of the sensor is defined as “t (top)”, and the displacement detection value of the lower sensor is defined as “b (bottom)”.

  10B, that is, the inner side displacement sensors 84t, 84b, 84f, and 84r and the outer side displacement sensors 94t, 94b, 94f, and 94r are accurately overlapped in the axial direction. This fact is consistent with the fact that the entire first displacement detector 70 described above substantially overlaps the second displacement detector 71 in the axial direction.

Returning to the story, displacement detection values of a total of eight sensors included in the sensor device 10 are defined as follows.
fi: displacement detection value of the displacement sensor 84f ri: displacement detection value of the displacement sensor 84r ti: displacement detection value of the displacement sensor 84t bi: displacement detection value of the displacement sensor 84b fo: displacement detection value of the displacement sensor 94f ro: displacement sensor 94r Displacement detection value of to: displacement detection value of displacement sensor 94t bo: displacement detection value of displacement sensor 94b

  FIG. 11 is a diagram schematically showing the positional relationship between the target member 73 and several displacement sensors when a translational load Fy in the y-axis direction acts on the wheel. Hereinafter, the independent variable (sFy) corresponding to the translation load Fy in the y-axis direction will be described with reference to FIG.

  As shown in FIG. 11, when a translational load Fy in the y-axis direction acts on the wheel, the second track member (rotating track member) is displaced in the direction of the load, and the positions of the annular grooves 134 and 135 are the axes. Deviation in direction. Therefore, as described above, the displacement detection values (output voltages in the present embodiment) fi, ri, ti, and bi of the inner displacement sensors all decrease with an increase in the axial movement amount δ, and the outer The displacement detection values fo, ro, to, and bo of the respective displacement sensors increase as the axial movement amount δ increases.

Therefore, as shown in FIG. 12, that is, a matrix diagram showing the correspondence between the independent variable calculated from each displacement sensor output and the actual load acting on the wheel, sFy calculated by the following equation (1) Is adopted as an independent variable corresponding to the translational load Fy in the y-axis direction.
sFy = (fi + ri + ti + bi) − (fo + ro + to + bo)
... (1)

  Thus, by taking the difference between the displacement detection value of each displacement sensor on the inner side and the displacement detection value of each displacement sensor on the outer side, the unit translational amount in the axial direction of the second track member that is a rotating raceway ring is determined. Since sFy is amplified, the detection sensitivity of the axial displacement of the sensor device 10 as a whole can be increased.

  The displacement detection value of the displacement in the x-axis direction and the displacement detection value of the displacement in the z-axis direction are obtained as follows.

  For the x-axis direction, a displacement detection value for the x-axis direction displacement is determined by the difference between the displacement detection value f for the front sensor and the displacement detection value r for the rear sensor, and for the z-axis direction, the displacement detection value t for the upper sensor The displacement detection value of the displacement in the z-axis direction is determined by the difference in the displacement detection value b of the lower sensor. Since the output of the front and rear sensors and the output of the upper and lower sensors are affected by the temperature in the same direction by the same amount, the temperature drift is eliminated by taking the difference as described above.

In the present embodiment, the displacement sensors 84t, 84b, 84f, 84r, 94t, 94b, 94f, and 94r are arranged on the inner side and the outer side, so that the respective positions on the inner side and the outer side are as follows. The displacement detection value for the displacement in the x-axis direction and the displacement detection value for the displacement in the z-axis direction are obtained.
Displacement detection value of displacement in the x-axis direction on the inner side xi = fi−ri
Displacement detection value of displacement in the z-axis direction on the inner side zi = −ti + bi
Displacement detection value of displacement in the x-axis direction on the outer side xo = fo-ro
Displacement detection value of displacement in the z-axis direction on the outer side zo = −to + bo

  The independent variable (sMz) corresponding to the moment load Mz around the z-axis is obtained as follows.

  FIG. 13 is a diagram illustrating the relationship between various variables in a pure moment state in which only the moment load Mz about the z-axis acts.

When the axial distance from the center O of the bearing device (see FIG. 1) to the detection position of the inner side displacement sensor is Li and the axial distance from the bearing center O to the detection position of the outer side displacement sensor is Lo, The displacement detection value corresponding to the moment load Mz is theoretically represented by mz calculated by the following equation (2). As shown in FIG. 13, this mz coincides with xi when θ is sufficiently small.
mz = Li × tan θ
= Li * tan ((xi-xo) / (Li-Lo))
... (2)

  However, since the annular grooves 134 and 135 are actually formed in the target member 73, FIG. 14, that is, the displacement of Mz and mz and xi when only the moment load Mz around the z-axis is applied. As shown in the figure showing the relationship with the detection value, mz does not match xi, and mz does not match the slope of the displacement detection value of xi.

Therefore, a correction coefficient obtained by dividing the slope of the xi line indicated by kz in FIG. 15 by the slope of the mz line is introduced. By multiplying mz by the correction coefficient kz, an independent variable sMz corresponding to the moment load Mz around the z-axis is obtained as shown in the following equation (3).
sMz = −mz × kz
... (3)

In Equation (3), the minus sign (−) on the right side is for making the sign coincide with other independent variables (such as sFy and sMx described below).

  The independent variable (sMx) corresponding to the moment load Mx about the x-axis is obtained as follows.

The x-axis direction and the z-axis direction have a relationship of coordinate conversion by 90 degrees. Therefore, the independent variable sMx corresponding to the moment load Mx around the x-axis can be calculated by the following equation (4) based on the same concept as in the case of sMz.
sMx = mx × kx
... (4)

  In the above equation (4), kx is a value defined in FIG. 15 and is a correction coefficient introduced for the same purpose as kz, and is obtained by dividing the slope of the zi line by the slope of the mx line. It is. This kx is obtained from the diagram shown in FIG. 16, which shows the relationship between Mx and displacement detection values of mx and zi when only the moment load Mx around the x axis is applied.

  The independent variable (sFz) corresponding to the translation load Fz in the z-axis direction and the independent variable (sFx) corresponding to the translation load Fx in the x-axis direction are respectively determined as follows.

  FIG. 17 is a diagram showing a deformed state of the second track member assuming a state in which a translational load Fx in the x-axis direction acts together with a moment load Mz around the z-axis, and shows a relationship between various variables. is there.

  The displacement detection value xi of the x-axis direction displacement on the inner side includes a component of the independent variable sMz corresponding to the moment load Mz around the z-axis and a component of the independent variable sFx corresponding to the translational weight Fx in the x-axis direction. It is. The independent variable sFx corresponding to the translational weight Fx in the x-axis direction can be obtained by subtracting sMz from the above xi.

The same applies to sFz, which is an independent variable corresponding to the translation load Fz in the z-axis direction. Therefore, the independent variable sFz based on the translational load Fz in the z-axis direction and the independent variable sFx based on the translational load Fx in the x-axis direction can be calculated by the following equations (5) and (6), respectively.
sFz = zi−mx × kx
... (5)
sFx = xi-mz × kz
... (6)

  FIG. 18 is a diagram schematically illustrating the calculation method of the variables sFx, sFy, sFz, sMx, and sMz described so far. As shown in FIG. 18, sFy is first obtained, and sFx, sFz, sMx, and sMz can be obtained based on the value.

  FIG. 19 shows the independent variables sFx, sFy, sFz, sMx, and sMz obtained by the above equations (1), (3), (4), (5), and (6), and the actual loads acting on the wheels. It is a matrix figure showing the correspondence with a certain Fx, Fy, Fz, Mx, and Mz.

  That is, Fx, Fy, Fz, Mx and Mz actually loaded on the wheel are input, and each independent variable sFx obtained by the equations (1), (3), (4), (5), (6) is used. , SFy, sFz, sMx and sMz are output, and a linear graph between these variables is formed into a matrix.

  As shown in the matrix diagram of FIG. 19, only sFx has a slope with respect to Fx, and other Fy, Fz, Mx, and Mz have no reaction, and similarly, the diagonal of the matrix diagram. Only the part is a straight line graph. Therefore, these five independent variables sFx, sFy, sFz, sMx and sMz are in a linearly independent relationship with the five component forces Fx, Fy, Fz, Mx and Mz which are actual loads acting on the wheels.

  For this reason, once those independent variables sFx, sFy, sFz, sMx and sMz are obtained, by solving the five-way simultaneous linear equations with five loads Fx, Fy, Fz, Mx and Mz acting on the wheels as unknowns, The respective loads Fx, Fy, Fz, Mx and Mz can be calculated.

  In the present embodiment, the signal processing unit 140 formed of an ECU or the like includes an arithmetic circuit that solves the above equations (1), (3), (4), (5), and (6) and a five-way simultaneous linear equation. (Hardware) or control program (software) is installed. For this reason, the actual loads Fx, Fy, Fz, Mx and Mz acting on the wheels are obtained based on the eight displacement detection values fi, ri, ti, bi, fo, ro, to and bo by each displacement sensor. Can do.

  FIG. 20 shows a method of extracting the displacement detection value from the detection value of each displacement sensor in each displacement sensor 84t, 84b, 84f, 84r, 94t, 94b, 94f, 94r, and each displacement sensor 84t, 84b, 84f. , 84r, 94t, 94b, 94f, 94r, is a diagram showing a method for obtaining the rotational speed of the inner shaft 1 from the detected values.

  Hereinafter, as an example, how to obtain a pulse signal representing a displacement detection value and a rotation speed for the displacement sensor 84t will be described. The displacement sensors 84b, 84f, 84r, 94t, 94b, 94f, and 94r are subjected to the same processing as the displacement sensor 84t. The signal processing for the displacement sensors 84b, 84f, 84r, 94t, 94b, 94f, and 94r will be omitted from the description of the signal processing of the displacement sensor 84t.

  FIG. 21 is a diagram illustrating an example of a detection value of the displacement sensor 84t. As shown in FIG. 21, the detection value of the displacement sensor 84t is based on the rotation pulse signal caused by the unevenness appearing on the outer peripheral surface of the annular portion 150 due to the groove 155 formed in the annular portion 150, and the detection of the displacement sensor 84t. And a load signal related to the relative position of the first cylindrical surface portion 151, the relative position of the second cylindrical surface portion 152, and the relative position of the outer peripheral surface of the annular portion 150 with respect to the surface.

  As shown in FIG. 20, the detection value from the displacement sensor 84t is input to a known saturation detection circuit 250 as an example of a displacement signal detection unit. FIG. 22 is a diagram illustrating an output signal of the saturation detection circuit 250. As shown in FIG. 22, the saturation line of the detection value of the displacement sensor 84 t is taken out by the saturation detection circuit 250, and the groove 155 on the outer peripheral surface of the annular portion 150 is obtained in the information on the position of the outer peripheral surface of the annular portion 150. While the information on the position of the annular portion 150 is removed, only the information on the position of the hill on the outer peripheral surface of the annular portion 150 is picked up.

  The load signal shown in FIG. 22 is a displacement detection value used for detecting the above-described plurality of loads. In this way, displacement detection values are obtained for the displacement sensors 84t, 84b, 84f, 84r, 94t, 94b, 94f, and 94r, and the values are processed by the gap detection circuit shown in FIG. . After that, the signal processed by the gap detection circuit is processed by a known sample and hold circuit 251 (see FIG. 20), and then the physical quantity calculation unit 252 (see FIG. 20) appropriately converts the analog signal into a digital signal. Thus, the loads Fx, Fy, Fz, Mx and Mz are calculated in the process shown in FIG.

  As shown in FIG. 20, the detection value from the displacement sensor 84t is input to a rotation speed detection circuit 253 as a rotation signal detection unit. The rotation speed detection circuit 253 compares the detection value from the displacement sensor 84t with the threshold value using a predetermined voltage value as a threshold value, and detects the detection value from the displacement sensor 84t as a pulse in which a high signal and a low signal are repeated. It is designed to convert to a signal.

  FIG. 23 is a diagram illustrating an example of an output signal of the rotation speed detection circuit 253. The high signal in the pulse signal is generated based on the detection of the groove 155 of the annular portion 150, while the low signal in the pulse signal is generated based on the detection of the hill of the annular portion 150. Based on the period of the pulse signal, the rotational speed of the annular portion 150, that is, the inner shaft 1, is calculated.

  The gap detection circuit, the sample hold circuit 251 and the physical quantity calculation unit 252 constitute a moment load calculation unit. The signal processing unit 140 includes the gap detection circuit, the saturation detection circuit 250, the sample hold circuit 251, and the physical quantity calculation unit 252.

  According to the rolling bearing device with a sensor of the above embodiment, the first displacement detector 70 is provided with the first displacement detector 70 and the second displacement detector 71 that are separated from each other in the axial direction. Of course, the translation load based on the translational displacement in the axial direction can be calculated based on the detection signal of the second displacement detection signal 71 and the displacement of the sensor-equipped rolling bearing device according to the axial position. The moment load acting on the sensor-equipped rolling bearing device can be calculated based on the variation in displacement.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, while the displacement detection part which is the outer peripheral surface of the target member 73 is mutually spaced apart in the circumferential direction of the said displacement detection part, and it is axially An annular portion 150 having a plurality of extending grooves 155 is provided, and the sensor device 10 is annular based on the output of the first displacement detector 70 and the output of at least one of the second displacement detectors 71. A rotation speed detection circuit 253 for detecting a signal associated with the rotation of the unit 150, and a signal associated with the displacement of the displacement detection unit from the output of the first displacement detection unit 70 and the output of the second displacement detection unit 71. Since it has a saturation detection circuit 250 that detects a signal associated with the displacement of the displacement detection part, by detecting the groove 155 of the annular part 150 and the position of the hill that continues to the groove 155 in the circumferential direction, Annular part 1 To be able to acquire a pulse signal according to a rotational speed of 0, it is possible to detect the rotational speed of the annular portion 150. That is, since the displacement detection unit for detecting the displacement forms an annular portion 150 as a pulsed signal generation unit, the displacement detection units 70 and 71 can also be used as a rotational speed detection function, The rolling bearing device with sensor can be made compact, and the manufacturing cost of the rolling bearing device with sensor can be suppressed.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, the axial position of the step part 156 between the annular part 150 and the 1st cylindrical part 151, and between the annular part 150 and the 2nd cylindrical part 152 are shown. By detecting the position of the step portion 157 in the axial direction, the axial displacement of the sensor-equipped rolling bearing device can be detected easily and easily, and the axial translational load can be easily detected.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, the surface of the cyclic | annular part 150 has favorable magnetic characteristics, a magnetic flux passes easily, and is a structure which does not generate | occur | produce an eddy current, ie, several steel plate 200 ( In the above embodiment, a silicon steel plate is used, but any steel plate can be used), and the loss of electrical signals due to the generation of eddy currents is reduced. And the sensitivity of the sensor can be increased.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since it is A <B, a groove process can be easily performed to the annular part 150. FIG. Further, since C <A + B, the resolution of the pulse signal can be increased. Further, since B <C, a short-time rotation speed can be calculated.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, the moment load which is acting on the wheel can be calculated in the moment load calculation part. Therefore, the rotational speed of the wheel and the moment load acting on the wheel can be calculated, and the operation control during the traveling of the vehicle can be accurately performed based on the information.

  In the rolling bearing device with a sensor of the above embodiment, the displacement detection unit is the outer peripheral surface of the target member 73 that is separate from the inner shaft 1. However, in the present invention, there is no target member and the displacement detection is performed. The part may be a part of the outer peripheral surface of the inner shaft. Moreover, in the rolling bearing device with a sensor of the said embodiment, it was the structure by which the inner ring | wheel 1 and the inner ring | wheel 2 separate from the inner shaft 1 were fitted, However, In this invention, there is no inner ring | wheel, and 2nd track The member may be composed of a single inner shaft, or may be composed of an inner shaft and a target member, and the inner shaft may have two raceway surfaces on the outer peripheral surface of the inner shaft.

  Further, in the rolling bearing device with sensor of the above embodiment, A <B, C <A + B, and B <C. However, in the present invention, A ≧ B may be satisfied, and C ≧ A + B. Or B ≧ C.

  The sensor device that can be used in the present invention is not limited to the sensor device 10 used in the above embodiment, and may be a sensor device partially shown in FIGS. 24, 25, and 26 below.

  Specifically, as in the sensor device 400 shown in FIG. 24, the target member 473 is not formed with the annular grooves 134 and 135, and is larger than the surrounding constituent materials at the positions where the annular grooves 134 and 135 existed ( Alternatively, annular bands 434 and 435 having a small magnetic permeability may be formed. For example, in the case of steel, the annular band portions 434 and 435 can be formed by changing the amount of carbon contained.

  In addition, as in the sensor device 500 shown in FIG. 25, in the target member 573, convex portions 541 and 542 whose outer peripheral surfaces are cylindrical surfaces are formed at the positions where the annular grooves 134 and 135 were formed in the above embodiment. You may form the cyclic | annular part 550 in which the outer diameter of a hill part is smaller than the convex parts 541 and 542 in the position where the cyclic | annular part 150 was formed in the said embodiment.

  In addition, as in the sensor device 600 shown in FIG. 26, inclined portions 643 and 644 whose inclination directions are opposite to each other in the axial section may be formed on the outer peripheral surface of the target member 673. An annular portion having a groove may be formed in a part of 644. In FIG. 26, both inclined portions 643 and 644 have a valley-shaped joint portion, but the joint portions may be both inclined portions having a mountain shape.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the displacement detection parts 70 and 71 were fixed to the case member 6, you may attach a displacement detection part directly to an outer ring | wheel in this invention. Furthermore, in the rolling bearing device with a sensor of the above embodiment, the outer ring 1 constitutes a fixed race member, and the inner shaft 2 on the inner peripheral side constitutes the rotary race member, but the inner shaft on the inner peripheral side etc. The fixed raceway member may be configured, and the outer ring may constitute the rotary raceway member.

  The sensor device that can be used in the present invention is not limited to the inductance type displacement sensor described in the embodiment. 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 that can detect the gap.

  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 hub unit which is one Embodiment of the rolling bearing apparatus with a sensor of this invention. It is an expanded sectional view of the periphery of the displacement detection part in FIG. It is a figure which shows the structure of the outer peripheral surface of a target member, and the relationship of the relative position of a 1st displacement detection part, a 2nd displacement detection part, and a target member. It is a figure which shows the surface of an annular part in detail. It is sectional drawing of the radial direction which passes a cyclic | annular part and a 1st displacement detection part, and is a figure explaining the arrangement configuration of the circumferential direction of a displacement sensor. It is a figure which shows an example of the gap detection circuit connected to the 1st displacement detection part. It is a figure which shows the positional relationship of the detection surface of a displacement sensor, a 1st annular groove, and a 2nd annular groove. It is a figure which shows the connection structure of a displacement detection part and the signal processing part located in the opposite side to a displacement detection part with respect to a cover member. It is a figure explaining the direction used by this embodiment. It is a figure explaining the definition of the sensor displacement detection value used by this embodiment. It is a figure explaining the definition of the sensor displacement detection value used by this embodiment. It is a figure which shows typically the positional relationship of a target member and several displacement sensors in case the translation load Fy of a y-axis direction acts on a wheel. It is a matrix figure which shows the correspondence of the independent variable calculated from each displacement sensor output, and the actual load which acts on a wheel. It is a figure which shows the relationship of the various variables of the state of the pure moment which only the moment load Mz around az axis acts. It is a figure which shows the relationship between Mz and the displacement detection value of mz and xi when only the moment load Mz around the z-axis is applied. It is a figure explaining a correction coefficient. It is a figure which shows the relationship between Mx and the displacement detection value of mx and zi when only the moment load Mx around the x-axis is applied. It is a figure which shows the deformation | transformation state of a 2nd track member on the assumption that the translation load Fx of a x-axis direction acts with the moment load Mz around az axis. It is a figure which shows the calculation method of variable sFx, sFy, sFz, sMx, and sMz in a diagrammatic manner. It is a matrix figure showing the correspondence of independent variables sFx, sFy, sFz, sMx, and sMz and Fx, Fy, Fz, Mx, and Mz that are actual loads acting on the wheels. In each displacement sensor, it is a figure which shows the method of extracting a displacement detection value from the detection value of each displacement sensor, and the method of calculating | requiring the rotational speed of an inner shaft from the detection value of each displacement sensor. It is a figure which shows an example of the detection value of a displacement sensor. It is a figure which shows the output signal of a saturation detection circuit. It is a figure which shows an example of the output signal of a rotation speed detection circuit. It is a figure which shows typically the modification of a sensor apparatus. It is a figure which shows typically the modification of a sensor apparatus. It is a figure which shows typically the modification of a sensor apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner shaft 2 Inner ring 3 Outer ring 4 1st ball 5 2nd ball 71 1st displacement detection part 72 2nd displacement detection part 73 Target member 84t, 84b, 84f, 84r, 94t, 94b, 94f, 94r Displacement sensor 140 Signal processor 150 Annular portion 151 First cylindrical surface portion 152 Second cylindrical surface portion 155 Groove 200 Silicon steel plate 250 Saturation detection circuit 252 Physical quantity detection unit 253 Rotational speed detection circuit

Claims (5)

A first track member having a track surface on the inner peripheral surface;
A second track member having a track surface and an annular displacement detector on the outer peripheral surface;
A rolling element disposed between the raceway surface of the first raceway member and the raceway surface of the second raceway member;
A sensor device for detecting a radial displacement of the displacement detection unit and an axial displacement of the displacement detection unit;
The displacement detection unit includes an annular part having a plurality of grooves extending in the axial direction and spaced from each other in the circumferential direction of the displacement detection unit,
The sensor device is
A first displacement detection unit having a detection surface opposed to the displacement detection unit in the radial direction;
A second displacement detector having a detection surface positioned in the first displacement detector at an interval in the axial direction and opposed to the displacement detector in the radial direction;
Based on the output of at least one of the first displacement detector and the second displacement detector, a signal associated with the relative rotation of the annular portion with respect to at least one of the first displacement detector and the second displacement detector. A rotation signal detector for detecting
A displacement signal detection unit that detects a signal accompanying the displacement of the displacement detection unit from the output of the first displacement detection unit and detects a signal accompanying the displacement of the displacement detection unit from the output of the second displacement detection unit And a rolling bearing device with a sensor. In the rolling bearing device with a sensor according to claim 1,
The displacement detection unit includes a first cylindrical surface portion connected to the annular portion via a step portion, and a step portion on the opposite side of the annular portion from the first cylindrical surface portion side, and the first cylinder. A second cylindrical surface portion located on the substantially same cylindrical surface as the surface portion,
Each groove extends in the axial direction from one end in the axial direction of the annular portion to the other end in the axial direction of the annular portion,
The first displacement detector and the second displacement detector are substantially overlapped when viewed from the axial direction,
The detection surface of the first displacement detection unit overlaps with the end portion of the first cylindrical surface portion on the annular portion side and the end portion of the annular portion on the first cylindrical surface portion side when viewed from the radial direction. On the other hand, the detection surface of the second displacement detection unit includes an end portion on the annular portion side of the second cylindrical surface portion and an end portion on the second cylindrical surface portion side of the annular portion as viewed from the radial direction. A rolling bearing device with a sensor, wherein In the rolling bearing device with a sensor according to claim 1 or 2,
The rolling bearing device with a sensor, wherein the surface of the annular portion is formed by laminating a plurality of steel plates in the axial direction. In the rolling bearing device with a sensor according to any one of claims 1 to 3,
The plurality of grooves have substantially the same width, are arranged at equal intervals in the circumferential direction,
The first displacement detection unit and the second displacement detection unit substantially overlap each other when viewed from the axial direction, and each of the first displacement detection unit and the second displacement detection unit is equally spaced in the circumferential direction. It consists of four arranged displacement sensors,
In the radial cross section passing through the annular portion and the first displacement detector,
Of the plurality of grooves, the two grooves adjacent in the circumferential direction are defined as a first groove and a second groove,
A hill located between the first groove and the second groove is an intermediate hill,
A straight line passing through the middle point of the intermediate hill and the center of the annular portion is a hill center passing straight line,
A straight line passing through one end of the first groove in the circumferential direction parallel to the hill center passing straight line, and a straight line passing through the other end in the circumferential direction of the first groove parallel to the hill center passing straight line A distance is A [mm],
A distance between a straight line parallel to the hill center passing straight line and passing through one end of the intermediate hill in the circumferential direction and a straight line parallel to the hill center passing straight line and passing through the other end in the circumferential direction of the intermediate hill Is B [mm],
When 1/4 of the length of the detection surface of the first displacement detector is C [mm],
A rolling bearing device with a sensor, wherein A <B, C <A + B, and B <C. In the rolling bearing device with a sensor according to claim 1,
The second track member has a rotor mounting flange for mounting the rotor, and the first track member has a vehicle body mounting flange for mounting the vehicle body,
The plurality of grooves are arranged at equal intervals in the circumferential direction,
The first displacement detection unit and the second displacement detection unit substantially overlap each other when viewed from the axial direction, and each of the first displacement detection unit and the second displacement detection unit is equally spaced in the circumferential direction. It consists of four arranged displacement sensors,
The displacement signal detection unit detects a signal associated with the displacement of the displacement detection unit from the signal output by each displacement sensor in each displacement sensor,
The sensor device receives a signal from the displacement signal detection unit and detects the displacement of the displacement detection unit of the displacement sensor of the first displacement detection unit in each of the displacement sensors of the first displacement detection unit. Calculating the difference between the accompanying signal and the signal accompanying the displacement of the displacement detection part of the displacement sensor of the second displacement detection part of the second displacement detection part substantially overlapping the axial direction of the displacement sensor of the first displacement detection part; A sensor-equipped rolling bearing device comprising a moment load calculating unit that calculates a plurality of moment loads acting on the wheel based on the difference.

Images