JP2008275508A - Rolling bearing device with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing device with a sensor capable of sensitively determining the moment load acting on a trajectory member and the axial translation load. <P>SOLUTION: The rolling bearing device with the sensor includes a rotational component estimator 701 that extracts a rotational synchronization component included in the rotation of an inner shaft 1 relative to an outer ring from each of a signal output by a first displacement detecting section and a signal output by a second displacement detecting section. The rotational component estimator 701 performs rotational operation and integration operation. <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 sensor device.

  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 by centrifugal force, etc., when the vehicle is turning In addition, there is a problem that it is impossible to obtain the translational load in the axial direction of the wheel.

In addition, there is a demand for improving the sensitivity of the sensor device and precisely measuring the load applied to the roller bearing in the sensor-equipped rolling bearing device.
Japanese Patent Laid-Open No. 2001-21577 (see FIG. 8)

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sensor-equipped rolling bearing device capable of obtaining a moment load acting on a raceway member and an axial translational load with high sensitivity.

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 peripheral surface;
A second raceway member having a raceway surface and an annular displacement detector on the circumferential 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 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;
A rotation signal extraction unit that extracts a rotation synchronization component based on relative rotation of the second track member with respect to the first track member from the signal output from the first displacement detection unit and the signal output from the second displacement detection unit. When,
A displacement signal calculation unit for calculating a signal associated with the displacement of the displacement detection unit based on the output of the first displacement detection unit, the output of the second displacement detection unit, and the output of the rotation signal extraction 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.

  According to the invention, in the rotation signal extraction unit, the second track member with respect to the first track member from the signal output from the first displacement detection unit and the signal output from the second displacement detection unit. Since the rotation synchronization component based on the relative rotation can be extracted, the displacement signal calculation unit removes the rotation synchronization component from the output of the first displacement detection unit and the output of the second displacement detection unit. Can do. Therefore, the load (translational load, rotational load) applied to the sensor-equipped rolling bearing device can be detected with high accuracy.

  Further, according to the present invention, the local phase angle of the second raceway member relative to the first raceway member is obtained by obtaining a local frequency in the radial phase angle of the rotation synchronization component extracted by the rotation signal extraction unit. The rotational speed in a short time can be detected. Therefore, the sensor device can be used also as the function of the ABS sensor, and the ABS signal can be detected at a low cost.

In one embodiment,
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 substantially equidistant in the circumferential direction. Consisting of four displacement sensors arranged in
The sensor device includes a first displacement that represents a displacement of the displacement detection unit on a first axis extending in the radial direction from a signal of the first displacement detection unit and a signal of the second displacement detection unit. An orthogonal component calculation unit that calculates a signal and a second displacement signal that is orthogonal to the first axis and that represents the displacement of the displacement detection unit on the second axis extending in the radial direction;
The rotation component extraction unit
The two shafts that rotate the first displacement signal and the second displacement signal at the same rotational speed as the relative rotational speed of the second track member with respect to the first track member and extend in the radial direction and orthogonal to each other A first arithmetic unit that converts the signal into two signals viewed from a first rotating coordinate system comprising:
A second arithmetic unit that performs time integration on each of the two signals output by the first arithmetic unit and outputs two signals;
The two signals output by the second calculation unit rotate in the opposite direction to the first rotational coordinate system at the same rotational speed as the first rotational coordinate system, and extend in the radial direction and are orthogonal to each other. And a third arithmetic unit that converts the signal into two signals as viewed from a second rotational coordinate system including two axes.

  According to the embodiment, the rotation synchronization component can be easily and accurately extracted from the signals output from the first and second displacement detectors.

  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 detection signal of the second displacement 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 the variation of the displacement, the moment load acting on the sensor-equipped rolling bearing device can be calculated.

  According to the rolling bearing device with a sensor of the present invention, the rotation signal extraction unit extracts the rotation synchronization component from each of the signal output from the first displacement detection unit and the signal output from the second displacement detection unit. Therefore, in the displacement signal calculation unit, the rotation synchronization component can be removed from the output of the first displacement detection unit and the output of the second displacement detection unit. The applied load (translational load, rotational load) can be detected with high accuracy.

  Moreover, according to the rolling bearing device with a sensor of the present invention, the second race member with respect to the first race member is obtained by obtaining a local frequency in the radial phase angle of the rotation synchronization component extracted by the rotation signal extraction unit. It is possible to detect a short-time rotational speed at the radial phase angle. Therefore, the sensor device can be used also as the function of the ABS sensor, and the ABS signal can be detected at a low cost.

  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 portion on the outer ring 3 side in the axial direction of the cylindrical member 52 is fixed to an end portion on the small diameter shaft portion 19 side of the outer peripheral surface of the outer ring 3 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. The lid member 53 prevents foreign matter 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 which is one end portion of the outer peripheral surface of the inner ring 2. The inner shaft 1, the inner ring 2, the nut 63, and the target member 73 constitute a second track member, and 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 displacement detection unit 71. The first displacement detector 70 substantially overlaps the second displacement detector 71 in the axial direction.

  As shown in FIG. 1, a sensor ring 83 and a sensor ring 93 are fixed to the inner peripheral surface of the cylindrical member 52. 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. The first displacement detector 70 has four displacement sensors 84 (see FIG. 2), while the second displacement detector 71 has four displacement sensors 94 (see FIG. 2). 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 are fixed to the case member 6 via sensor rings 83 and 93. Therefore, after fixing the first displacement detector 70 and the second displacement detector 71 to the case member 6 via the sensor rings 83 and 93, the case member 6 is fixed to the outer peripheral surface of the outer ring 3 as described above. The first and second displacement detectors 70 and 71 can be easily fixed to the hub unit simply by fixing 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.

  Although not shown in FIGS. 1 and 2, a plurality of the four displacement sensors 84 are arranged at predetermined intervals in the circumferential direction in the radially inner portion of the sensor ring 83 (in the present embodiment, On the other hand, a plurality of four displacement sensors 94 are arranged at predetermined intervals in the circumferential direction in the radially inner portion of the sensor ring 93 (this is arranged at regular intervals). In the embodiment, they are arranged at regular intervals in the circumferential direction).

  FIG. 3 is a diagram illustrating the arrangement configuration of the four displacement sensors 94 in the circumferential direction. Although not described, the four displacement sensors 84 also have the same circumferential arrangement as the four displacement sensors 94. Also, in FIG. 3, reference numeral 75 is a flange of the outer ring 3 indicated by 75 in FIG.

  As shown in FIG. 3, each displacement sensor 94 includes a coil element 100 a and a coil element 100 b that are arranged close to each other in the circumferential direction to form a pair. The four displacement sensors 94 are substantially radially opposed to the portion of the target member 73 that is located at the uppermost position in the state where the rolling bearing device with sensor (in this embodiment, the hub unit) is installed at a predetermined position. At a position facing the most vertically downward portion of the target member 73 in a substantially radial direction, and at a position in the target member 73 at the most front side of the vehicle to which the rolling bearing device with a sensor is attached. And a position in the target member 73 that faces the most rearward position of the vehicle to which the rolling bearing device with a sensor is attached, in a position that is substantially in the radial direction. The four displacement sensors 84 substantially overlap the four displacement sensors 94 in the axial direction.

  In each group, each of the coil element 100a and the coil element 100b making a pair has an independent detection surface, and the coil element 100a and the coil element 100b making a pair are connected in series. The sensor ring 93 has a pair of magnetic poles 93a and 93b protruding inward in the radial direction at an end portion on the inner side in the radial direction. The coil element 100a has a coil wound around the magnetic pole 93a, while the coil element 100b has a coil wound around the magnetic pole 93b. In each of the magnetic pole 93a and the magnetic pole 93b, the radially inner end face 28 is a detection surface. These detection surfaces are opposed to the outer peripheral surface of the target member 73 in the radial direction at intervals.

  In the following, a displacement sensor that is substantially radially opposed to a portion of the target member 73 that is positioned at the uppermost vertical position in a state where the rolling bearing device with sensor (in this embodiment, a hub unit) is installed at a predetermined position. And a subscript b is added to a displacement sensor facing substantially the radial direction to a portion of the target member 73 that is positioned at the most vertically lower position, and this sensor-equipped rolling bearing device is attached to the target member 73. A displacement sensor that is substantially radially opposed to the frontmost position of the vehicle is attached with a suffix f, and the position of the rearmost vehicle in the target member 73 to which the rolling bearing device with the sensor is attached is attached. A subscript r is attached to a displacement sensor facing substantially in the radial direction.

  FIG. 4 is a diagram illustrating a positional relationship between the detection surface A1 of the displacement sensor 84t, the detection surface A2 of the displacement sensor 94t, and the displacement detection unit.

  As shown in FIG. 4, the displacement detection unit that is the outer peripheral surface of the target member 73 includes a first annular groove 134 and a second annular groove 135. The first annular groove 134 and the second annular groove 135 extend in the circumferential direction. The second annular groove 135 is located on the wheel side of the first annular groove 134 with an axial distance from the first annular groove 134.

  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. 4, in the axial direction, the center 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 center 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). (A difference in displacement detection value of a displacement sensor having the same subscript) is amplified with respect to a unit translation amount in the axial direction of the second track member, and thereby the axis of the sensor device 10 is amplified. It is possible to increase the detection sensitivity of the direction displacement.

  In contrast to the arrangement shown in FIG. 4, the inner first annular groove is shifted to the outer side with respect to the detection surface of the first displacement detector, and the outer second annular groove is detected as the second displacement. In this case, the same effects as described above can be obtained.

  FIG. 5 is a diagram illustrating an example of a gap detection circuit connected to each of the first displacement detection unit 70 and the second displacement detection unit 71.

  As shown in FIG. 5, in each of the first displacement detector 70 and the second displacement detector 71, each of the two sets of coil elements 100 a and coil elements 100 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 two sets of the coil element 100a and the coil element 100b. A synchronization capacitor 131 is connected in parallel to the two sets of coil elements 100a and 100b.

  Then, the output voltages (detected values) of the one coil element 100a and the coil element 100b and the other coil element 100a and the coil element 100b are input to the differential amplifier 132, and the output voltage corresponding to the direction of the same straight line. By setting (detected value), temperature drift is removed. Although not shown, the other two sets of coil element 100a and coil element 100b positioned in the front-rear direction are also removed from the temperature drift by taking the difference with the differential amplifier in the same manner as described above. The gap detection circuit shown in FIG. 5 is an example of an orthogonal component calculation unit. In this example, the first axis corresponds to the vertical direction, and the second axis corresponds to the front-rear direction.

  In each of the displacement sensors 84 and 94, the inductance of the coil element 100a (or the coil element 100b) is L, the area of the detection surface is A, the magnetic permeability is μ, the number of turns of the coil is N, and the target member 73 from the detection surface. If the interval (gap) 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 84 and 94 changes and the output voltage changes. Therefore, the radial gap from the detection surface of the displacement sensors 84 and 94 to the target member 73 can be detected by detecting the fluctuation of the output voltage.

  Each of the displacement sensors 84 and 94 has an independent detection surface with respect to the target member 73 and has a structure in which a pair of coil elements 100a and 100b are connected in series. In addition, compared with the case where one coil element 200 constitutes one displacement sensor, the generated magnetic flux density can be increased. Therefore, the detection sensitivity of the gap with the target member 73 can be increased.

  FIG. 7 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 displacement detection units 70 and 71 with respect to the lid member 53. The signal processing unit 140 is composed of an ECU or the like.

  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. 8 is a diagram illustrating the direction used in the present embodiment, and FIGS. 9 and 10 are diagrams illustrating the definition of the sensor displacement detection value used in the present embodiment. FIG. 9 is a diagram of the displacement sensor as viewed from the outside in the radial direction, and FIG. 10 is a diagram of the displacement sensor as viewed from the axial direction. In FIG. 10, for the sake of simplicity, two coil elements 100a and 100b (see FIG. 3) adjacent in the circumferential direction are represented by one coil element.

  As shown in FIG. 8, 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 FIGS. 9 and 10, the subscript “i” is used for the displacement detection values of the four displacement sensors 84 on the inner side (the center side of the vehicle body), and the four on the outer side (the wheel side) are used. The subscript “o” is used for the displacement sensor 94.

For reconfirmation, when the hub unit is installed at a predetermined position,
A sensor 84f (f is an abbreviation of front) is a sensor 84 that is installed at a position in the target member 73 that faces the most front side position of the vehicle to which the hub unit is attached.
A sensor 84 r (r is an abbreviation for rear) is defined as a sensor 84 r (r is an abbreviation for rear) in the target member 73, which is installed at a position substantially opposite to the position on the most rear side of the vehicle to which the hub unit is attached.
The sensor 84 t (t is an abbreviation of top) is a sensor 84 that is installed at a position that is substantially radially opposite to the portion of the target member 73 that is located at the uppermost vertical position.
A sensor 84 installed at a position substantially opposite to the portion of the target member 73 that is positioned at the most vertically lower position in the radial direction is referred to as a sensor 84b (b is an abbreviation for bottom).

In the future, in the sensor displacement detection value,
Use the subscript “f” for the displacement detection value of the front sensor,
Use the subscript “r” for the displacement detection value of the rear sensor,
Use the subscript “t” for the displacement detection value of the upper sensor,
The subscript “b” is used for the displacement detection value of the lower sensor.

  The fact shown in FIG. 10, that is, the fact that the inner side displacement sensors 84t, 84b, 84f, 84r and the outer side displacement sensors 94t, 94b, 94f, 94r substantially overlap in the axial direction. Is consistent with the fact that the 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 positions on the inner side and the outer side are as follows. As shown in the following equation (2), a displacement detection value for displacement in the x-axis direction and a displacement detection value for displacement in the z-axis direction are obtained. Here, it goes without saying that the value of the following equation (2) corresponds to the output of the gap detection circuit shown in FIG.
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
... (2)

  In the following formulas (3) to (7), xi, xo, zi, zo represented by the formulas are not xi, xo, zi, zo represented by the formula (2), but xi ′ referred to below. , Xo ′, zi ′, zo ′. xi ', xo', zi ', and zo' are detection values obtained by removing a rotation synchronization component that is noise from each of xi, xo, zi, and zo represented by Expression (2). The method for obtaining xi ', xo', zi ', zo' will be described in detail with reference to FIG.

  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 (3). 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))
... (3)

  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 about the z-axis is obtained as shown in the following equation (4).
sMz = −mz × kz
... (4)

In equation (4), 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 about the x axis can be calculated by the following equation (5) based on the same concept as in the case of sMz.
sMx = mx × kx
... (5)

  In the above equation (5), 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 due to the translational load Fz in the z-axis direction and the independent variable sFx due to the translational load Fx in the x-axis direction can be calculated by the following equations (6) and (7), respectively.
sFz = zi−mx × kx
... (6)
sFx = xi-mz × kz
... (7)

  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), (4), (5), (6), and (7), 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), (4), (5), (6), (7) is obtained. , 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 composed of an ECU or the like includes an arithmetic circuit that solves the above-described equations (1), (4), (5), (6), (7) and a quinary 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 is a diagram for explaining a mechanism for removing the rotation synchronization component from the output signal of the gap detection circuit.

  Xi (xi = fi−ri), which is a displacement detection value of displacement in the x-axis direction on the inner side, zi (zi = −ti + bi), which is a displacement detection value of displacement in the z-axis direction on the inner side, outer Xo (xo = fo−ro) which is a displacement detection value of the displacement in the x-axis direction on the side, and zo (zo = −to + bo) which is a displacement detection value of the displacement in the z-axis direction on the outer side. Includes a rotation synchronization signal accompanying the rotation of the inner shaft 1, and this rotation synchronization signal is noise with respect to the load signal (displacement signal).

  Therefore, it is necessary to remove the rotation synchronization signal component that is noise from the four displacement detection values. In this embodiment, the rotation synchronization signal is removed from the xi, zi, xo, and zo, and a more accurate load signal (displacement signal) is extracted from the xi and the zi. In this embodiment, in addition to removing the rotation synchronization signal from the xi, zi, xo and zo, an ABS signal is generated based on the rotation synchronization signal.

  Hereinafter, a mechanism for removing the rotation synchronization signal from xi and zi and a mechanism for generating an ABS signal based on the rotation synchronization signal will be described in detail with reference to FIG. 20 and FIGS. 21 to 25 below. To do.

  Although not described, xo (xo = fo−ro), which is a displacement detection value of displacement in the x-axis direction on the outer side, and zo (zo, which is a displacement detection value of displacement in the z-axis direction, on the outer side. = -To + bo), the rotational synchronization component is removed by the same method.

  As shown in FIG. 20, a signal including a force signal and a rotation signal (specifically, xi, zi in the above equation (2)) is output to a rotation component estimator 701 as an example of a rotation signal extraction unit. Then, the rotation component estimator 701 extracts the rotation synchronization component (x3, y3). From this, by subtracting x3 from xi, the rotational synchronization component that is noise can be eliminated from xi, and by subtracting z3 from zi, the rotational synchronization component that is noise can be eliminated from zi.

  Further, the rotational synchronization component is made up and down with a predetermined threshold as a boundary and binarized to be a pulse signal, thereby obtaining an ABS signal.

  FIG. 21 is a diagram showing a mechanism for extracting a rotation synchronization component in the rotation component estimator 701. In FIG. In FIG. 21, the phase difference 0 indicates that the phase difference between the orthogonal coordinate system set for the inner shaft 1 and the rotational coordinate system of the first calculation unit 901 described below is 0. .

  The rotation component estimator 701 includes a first calculation unit 901, a second calculation unit, and a third calculation unit 904. The second calculation unit includes a first integrator 902, a second integrator 903, It is made up of.

First, in the first calculation unit 901, the above-mentioned xi and zi, which are input signals including a rotation synchronization component, are set as a two-dimensional vector (xi, zi), and the two-dimensional vector (xi, zi) is set below (8 The R1 calculation corresponding to the rotation calculation of −ωt shown by the formula (1) is performed. Here, each of xi and zi is made up of the sum of a rotational synchronization component and a non-rotation synchronization component that vary with ωt.

  A two-dimensional vector (x1, z1), which is an output of the R1 calculation, indicates a displacement signal when viewed from a rotating coordinate system that rotates at the same rotation as the rotating body (specifically, the displacement detection unit). . This signal becomes a fluctuation signal due to the non-rotation synchronization component. This signal component has the same frequency as the rotation synchronization frequency, and has an amplitude component of a non-rotation synchronization component viewed from the X direction or the Z direction.

  Here, although not described in detail, the rotational speed of the displacement detection section, that is, the rotational speed of the inner shaft 1 is formed, for example, by forming a concave portion at one place in the circumferential direction of the inner shaft 1. Calculation is performed by detecting at least one of the detection unit 70 and the second displacement detection unit 71. Here, it should be noted that the rotational speed of the inner shaft 1 is not an ABS signal representing the instantaneous rotational speed of the rotation of the inner shaft 1 at each circumferential phase angle. This is because the rotational speed of the inner shaft 1 is not a signal representing the instantaneous rotational speed of the rotation of the inner shaft 1 at each circumferential phase angle.

Next, as shown in the following equation (9), x1 is time integrated by the first integrator 902 to calculate x2, and z1 is time integrated by the second integrator 903 to calculate z2. In this way, the x1 signal is converted into the x2 signal, and the z1 signal is converted into the z2 signal.

  The output signals x2 and z2 of the first and second integrators 902 and 903 that receive x1 and z1 as input are the rotation coordinate components of xi and zi and the rotation coordinate signal as viewed from the rotation coordinate system synchronized with the rotation. It is a signal having information on “how much phase difference and amplitude it has”. Each of the outputs of the first integrator 902 and the second integrator 903 has an establishment time determined by the gain of the integrator, but after a certain time has elapsed, it converges to a constant value.

Finally, in the third calculation unit 904, x2 and z2 are set as a two-dimensional vector (x2, z2), and the two-dimensional vector (x2, y2) is converted into a rotation calculation of ωt shown by the following equation (10). R2 calculation corresponding to is performed.

  The R2 calculation corresponds to outputting an X-direction component or a Z-direction component when viewed from the fixed coordinate system based on the phase difference information and the amplitude information. The signal (x3, y3) corresponds to a signal component obtained by extracting only the rotation synchronization signal with an opposite phase.

  (Xs, zs) obtained by adding (x3, z3) to (xi, zi) is calculated. This (xs, zs) is nothing but (xi ', yi') and is (xi, zi) expressed in the above formulas (4) to (7). The method for obtaining (xo ', yo') from (xo, yo) is the same as the method for obtaining (xi ', yi') from (xi, yi).

  The calculation unit that calculates (xs, zs) by adding (x3, z3) to (xi, zi) constitutes a displacement signal calculation unit.

  22 to 25 are orthogonal coordinate systems set on the inner shaft 1 (this orthogonal coordinate system is positioned with respect to the position of the concave portion provided at one place in the circumferential direction of the inner shaft 1, for example). 21 and the phase difference from the rotational coordinate system of the first calculation unit 901 described below is not 0, but is π / 4, 3π / 8, π / 2, 3π / 4. Different from the example.

  As shown in FIGS. 21 to 25, the phase difference between the orthogonal coordinate system set for the inner shaft 1 and the rotational coordinate system of the first calculation unit 901 described below has an influence on the extraction of the load signal. There is no. Therefore, the rotating coordinate system can be set freely.

  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, it is possible to calculate the translational load based on the translational displacement in the axial direction based on the detection signal of the second displacement detection signal 71 and the detection signal of the second displacement detection signal 71. The variation can be detected, and the moment load acting on the sensor-equipped rolling bearing device can be calculated based on the variation of the displacement.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, in the rotation component estimator 701 as a rotation signal extraction part, the signal which the 1st displacement detection part 70 output, and the signal which the 2nd displacement detection part 71 output Since the rotation synchronization component based on the relative rotation of the inner shaft 1 with respect to the outer ring 3 can be extracted from each of them, the displacement signal calculation unit uses the output of the first displacement detection unit 70 and the output of the second displacement detection unit 71. The rotation synchronization component can be removed. Therefore, the load (translational load, rotational load) applied to the sensor-equipped rolling bearing device can be detected with high accuracy.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, the diameter of the inner shaft 1 with respect to the outer ring | wheel 3 is calculated | required by calculating | requiring the local frequency in the phase angle of the radial direction of the rotation synchronous component extracted by the rotation component estimation device 701. A short-time rotation speed at the phase angle of the direction can be detected. Therefore, since the sensor device 10 can also function as an ABS sensor, an ABS signal can be detected at a low cost.

  Further, according to the rolling bearing device with sensor of the above embodiment, the rotation component estimator 701 uses the rotation calculation and the integration calculation to extract the rotation synchronization component, so the rotation synchronization component is extracted with high accuracy. be able to.

  In the hub unit of the above embodiment, the displacement detectors 70 and 71 are fixed to the case member 6. However, in the present invention, the displacement detector may be directly attached to the outer ring.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the displacement detection part was the outer peripheral surface of the target member 73 separate from the inner shaft 1, in this invention, there is no target member and displacement detection is carried out. 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 a sensor of the above embodiment, the outer ring 1 constitutes a fixed race member, and the inner shaft 2 etc. on the inner peripheral side constitutes the rotary race member, but the inner shaft etc. on the inner peripheral side 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 sensor device 10 used in the above-described embodiment, and may be a sensor device partially shown in FIGS. 26, 27, and 28 below.

  Specifically, as in the sensor device 400 shown in FIG. 26, 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. 27, 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. 28, 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. 28, both inclined portions 643 and 644 have a valley-shaped joint portion, but the joint portions may be both inclined portions that form a mountain shape.

  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 device 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, the rolling element of the rolling bearing with a sensor manufactured is a roller. 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 1st displacement detection part in FIG. It is a figure explaining the arrangement configuration of the circumferential direction of four displacement sensors. It is a figure which shows the positional relationship of the detection surface of a displacement sensor, and a displacement detection part. It is a figure which shows an example of the gap detection circuit connected to each of a 1st displacement detection part and a 2nd displacement detection part. In the displacement sensor of this embodiment, it is a figure explaining that the magnetic flux density to generate | occur | produce can be enlarged compared with the case where one displacement sensor is comprised with one coil element. 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 at the time of making only the moment load Mz around z-axis act, and the displacement detection value of mz and xi. 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. It is a figure explaining the mechanism which removes a rotation synchronous component from the output signal of a gap detection circuit. It is a figure which shows the mechanism of extraction of a rotation synchronous component in a rotation component estimator. It is a figure which shows the mechanism of extraction of a rotation synchronous component in a rotation component estimator. It is a figure which shows the mechanism of extraction of a rotation synchronous component in a rotation component estimator. It is a figure which shows the mechanism of extraction of a rotation synchronous component in a rotation component estimator. It is a figure which shows the mechanism of extraction of a rotation synchronous component in a rotation component estimator. It is a schematic diagram explaining the sensor apparatus which can be used by this invention. It is a schematic diagram explaining the sensor apparatus which can be used by this invention. It is a schematic diagram explaining the sensor apparatus which can be used by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner shaft 2 Inner ring 3 Outer ring 4 1st ball 5 2nd ball 70 1st displacement detection part 71 2nd displacement detection part 73 Target member 84t, 84b, 84f, 84r, 94t, 94b, 94f, 94r Displacement sensor 140 Signal processing unit 701 Rotational component estimator 901 First computing unit 902 First integrator 903 Second integrator 904 Third computing unit

Claims (2)

A first track member having a track surface on the peripheral surface;
A second raceway member having a raceway surface and an annular displacement detector on the circumferential 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 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;
A rotation signal extraction unit that extracts a rotation synchronization component based on relative rotation of the second track member with respect to the first track member from the signal output from the first displacement detection unit and the signal output from the second displacement detection unit. When,
A displacement signal calculation unit for calculating a signal associated with the displacement of the displacement detection unit based on the output of the first displacement detection unit, the output of the second displacement detection unit, and the output of the rotation signal extraction unit; A rolling bearing device with a sensor characterized by comprising: In the rolling bearing device with a sensor according to claim 1,
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 substantially equidistant in the circumferential direction. Consisting of four displacement sensors arranged in
The sensor device includes a first displacement that represents a displacement of the displacement detection unit on a first axis extending in the radial direction from a signal of the first displacement detection unit and a signal of the second displacement detection unit. An orthogonal component calculation unit that calculates a signal and a second displacement signal that is orthogonal to the first axis and that represents the displacement of the displacement detection unit on the second axis extending in the radial direction;
The rotation component extraction unit
The two shafts that rotate the first displacement signal and the second displacement signal at the same rotational speed as the relative rotational speed of the second track member with respect to the first track member and extend in the radial direction and orthogonal to each other A first arithmetic unit that converts the signal into two signals viewed from a first rotating coordinate system comprising:
A second arithmetic unit that performs time integration on each of the two signals output by the first arithmetic unit and outputs two signals;
The two signals output by the second calculation unit rotate in the opposite direction to the first rotational coordinate system at the same rotational speed as the first rotational coordinate system, and extend in the radial direction and are orthogonal to each other. A sensor-equipped rolling bearing device, comprising: a third calculation unit that converts the signal into two signals as viewed from a second rotational coordinate system including two axes.

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