Detection device

Abstract

To provide a detection device capable of suppressing temperature rise of an excitation coil and a reception coil.SOLUTION: The detection device includes a sensor member 100 and a target member 80. The sensor member 100 is provided at a position shifted to the knuckle 15 side in the axial direction with respect to the flange portion 62 of the hub bearing 40. The target member 80 is provided with convex portions and concave portions alternately in the circumferential direction. The sensor member includes an exciting coil and a receiving coil. The detection device includes an inlet pipe, an intermediate pipe 153, and an outlet pipe through which cooling water for cooling the exciting coil and the receiving coil flows.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a detection device. [Background technology]

[0002] Conventionally, an inductive rotation angle sensor has been known that includes a rotor provided on a rotating shaft of a mechanical device and a sensor body disposed opposite the rotor in the axial direction of the rotating shaft. Such a sensor is described, for example, in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5447345 Summary of the Invention [Problem to be solved by the invention]

[0004] A detection device is known that is applied to a mechanical device that includes a rotating body and a hub bearing that rotatably supports the rotating body relative to a base. The hub bearing includes a first bearing member (e.g., an outer ring member), a second bearing member (e.g., an inner ring member), and rolling elements. The first bearing member has a first cylindrical portion that extends in the axial direction, which is the direction of the rotational center axis of the hub bearing, and is fixed to the base. The second bearing member has a second cylindrical portion that is provided at a position facing the first cylindrical portion in a radial direction perpendicular to the axial direction, and a flange portion that extends radially outward from the second cylindrical portion. The rolling elements are provided between the first cylindrical portion and the second cylindrical portion.

[0005] The detection device includes a sensor member and a detection target portion as components for detecting a force acting on the rotating body. The sensor member is provided at a position offset toward the base portion relative to the flange portion in the axial direction. The detection target portion has an annular shape extending in the circumferential direction of the second cylindrical portion, centered on the central axis of rotation. The detection target portion is provided with convex portions that protrude toward the base portion in the axial direction and portions that recede from the convex portions on the opposite side of the base portion in the axial direction, alternately provided in the circumferential direction.

[0006] The sensor member includes an excitation coil to which an excitation voltage is supplied, and a receiving coil that, when the excitation voltage is supplied to the excitation coil, induces a voltage and outputs a voltage signal corresponding to the relative displacement of the detection target with respect to the excitation coil. The force acting on the rotating body is detected based on the output voltage signal.

[0007] When an excitation voltage is supplied to the excitation coil, a current flows through the excitation coil. When a voltage is induced in the receiving coil, a current flows through the receiving coil. When a current flows through the excitation coil and the receiving coil, the temperatures of the excitation coil and the receiving coil rise. The temperature rise of each coil affects the voltage signal output from the receiving coil. As a result, there is a concern that the accuracy of force detection may decrease.

[0008] A primary object of the present disclosure is to provide a detection device that can suppress temperature increases in an excitation coil and a receiving coil. [Means for solving the problem]

[0009] The present disclosure provides a detection device applied to a mechanical device, The mechanical device is A rotating body; a hub bearing that supports the rotating body rotatably relative to a base portion; Equipped with The hub bearing is a first bearing member having a first cylindrical portion extending in an axial direction that is the direction of the rotational center axis of the hub bearing and fixed to the base portion; a second bearing member including a second cylindrical portion provided at a position facing the first cylindrical portion in a radial direction perpendicular to the axial direction, and a flange portion extending radially outward from the second cylindrical portion; a rolling element provided between the first cylindrical portion and the second cylindrical portion; the second bearing member is rotatably supported relative to the base portion, a sensor member provided at a position shifted toward the base portion relative to the flange portion in the axial direction; a detection target portion that is provided in a portion of the flange portion that faces the sensor member in the axial direction and has an annular shape that extends in a circumferential direction of the second cylindrical portion; Equipped with The detection target portion is provided with convex portions that protrude toward the base portion in the axial direction and portions that recede toward the opposite side of the base portion from the convex portions in the axial direction, alternately in the circumferential direction, The sensor member an excitation coil to which an excitation voltage is supplied; a receiving coil that induces a voltage when an excitation voltage is supplied to the exciting coil and outputs a voltage signal corresponding to the relative displacement of the detection target portion with respect to the receiving coil; It has.

[0010] The present disclosure includes a cooling channel through which a liquid cooling fluid flows to cool the excitation coil and the receiving coil.

[0011] This makes it possible to suppress the temperature rise of the excitation coil and the receiving coil. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 2 is a perspective view of a wheel unit according to the first embodiment. [Figure 2] FIG. [Figure 3] Enlarged view of a portion of Figure 2. [Figure 4] FIG. [Figure 5]FIG. 4 is a perspective view of the wheel unit as seen from the knuckle side. [Figure 6] FIG. 4 is a perspective view of the bracket member and the sensor member as viewed from the flange portion side. [Figure 7] FIG. 10 is a view of the target member as seen from the knuckle side. [Figure 8] FIG. [Figure 9] FIG. 2 is a diagram showing the electrical configuration of a sensor member and a processing unit. [Figure 10] FIG. 4 is a view of the bracket member as seen from the flange portion side. [Figure 11] FIG. 10 is a view of the bracket member from the knuckle side. [Figure 12] FIG. 1 is a schematic diagram showing the cooling water circulation path of an in-vehicle system. [Figure 13] FIG. 10 is a perspective view of a hub bearing, a bracket member, and the like according to a second embodiment, as viewed from the knuckle side. [Figure 14] View of the wheel unit from the knuckle side. [Figure 15] FIG. 10 is a view of the bracket member and the sensor member as seen from the flange portion side. [Figure 16] Cross-sectional view taken along line 16-16 in Figure 15. [Figure 17] FIG. [Figure 18] FIG. [Figure 19] FIG. 10 is an exploded perspective view of a bracket member according to a modified example of the second embodiment. [Figure 20] FIG. 11 is a perspective view of a hub bearing, a bracket member, and the like according to a third embodiment, as viewed from the flange portion side. [Figure 21] FIG. 4 is a perspective view of the hub bearing, the bracket member, etc., as viewed from the knuckle side. [Figure 22] FIG. [Figure 23] View of the first and second thick sections from the knuckle side. [Figure 24] FIG. [Figure 25] FIG. [Figure 26]FIG. 10 is a view of the bracket member from the knuckle side. [Figure 27] Cross-sectional view taken along line 27-27 in Figure 26. [Figure 28] FIG. 10 is a perspective view of a hub bearing and a sensor member according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Several embodiments will be described with reference to the drawings. In several embodiments, functionally and / or structurally corresponding and / or associated parts may be assigned the same reference numerals or reference numerals that differ in the hundredth or more digit. For corresponding and / or associated parts, reference may be made to the descriptions of other embodiments.

[0014] First Embodiment A first embodiment of a detection device according to the present disclosure will be described below with reference to the drawings. The detection device of this embodiment is configured to be able to calculate the force acting on wheels (drive wheels or driven wheels) as rotating bodies. A vehicle equipped with wheels is, for example, a four-wheeled passenger vehicle (for example, private or commercial use) having two front wheels and two rear wheels. However, the vehicle is not limited to this, and may be a vehicle other than a four-wheeled vehicle, such as a two-wheeled vehicle. Furthermore, the use of the vehicle is not limited to passenger use.

[0015] The wheel unit 10 as a mechanical device will be described using Figures 1 to 11. To explain some of the figures, Figure 1 is a perspective cross-sectional view in which the wheel unit 10 is partially cut away, and Figure 2 is a cross-sectional view in which the wheel unit 10 is cut along a plane that passes through the center of rotation of the wheel unit 10 and extends vertically. Figure 3 is a partially enlarged view of Figure 2. Figure 4 is an exploded perspective view of the wheel unit 10. Figure 5 is a perspective view of the wheel unit 10 as viewed from the knuckle 15 side.

[0016] As shown in Figures 1 and 2, the wheel unit 10 includes a wheel 11 and a tire 14 that constitute a wheel. The wheel 11 includes a cylindrical rim portion 12 and a disc portion 13 provided at the outer end of the rim portion 12 in the vehicle width direction. The disc portion 13 includes a disc mounting portion 18 located in the center of the disc portion 13, and spoke portions 19 that extend radially from the disc mounting portion 18 to the rim portion 12. The tire 14 is mounted on the outer periphery of the rim portion 12.

[0017] As shown in Figures 1 to 5, the wheel unit 10 includes a brake device 20 and a hub bearing 40. The brake device 20 is a disc-type friction braking device and includes a disc rotor 21 that is disk-shaped overall, and a brake caliper 33. The brake caliper 33 is operated by hydraulic pressure, an electric signal, or the like, and includes a pair of brake pads that come into contact with the disc rotor 21 to generate braking force, a piston that presses the brake pads against the disc rotor 21, and a caliper body that supports the brake pads and the piston. As shown in Figure 4, the brake caliper 33 is fixed to the knuckle 15, which is its base, by a bolt 34.

[0018] In the following, the direction in which the rotational center axis of the hub bearing 40 (specifically, for example, the inner ring member 60 of the hub bearing 40) extends is referred to as the axial direction, the direction extending radially from the rotational center axis is referred to as the radial direction, and the direction extending circumferentially around the rotational center axis is referred to as the circumferential direction.

[0019] The disc rotor 21 of this embodiment is a ventilated disc having an internal cavity for ventilation. As shown in FIG. 2 , the disc rotor 21 has a hat portion 22 and a disc sliding portion 23. The hat portion 22 is attached to the hub bearing 40. The hat portion 22 has a disk-shaped bottom surface portion 24 and a disc peripheral wall portion 25. A mounting hole 26 is formed in the center of the bottom surface portion 24. Bolt insertion holes 27 that axially penetrate the bottom surface portion 24 are formed in a circumferential direction around the mounting hole 26. The disc rotor 21 is connected to the hub bearing 40 using the mounting hole 26 and the bolt insertion holes 27. The disc peripheral wall portion 25 is cylindrical and extends from the outer circumferential edge of the bottom surface portion 24, forming the peripheral surface of the hat portion 22.

[0020] A disc sliding portion 23 is connected to the end of the disc peripheral wall portion 25 opposite the bottom surface portion 24. The disc sliding portion 23 is formed to protrude outward in an annular shape from the disc peripheral wall portion 25. The front and back surfaces of the disc sliding portion 23 form a pair of sliding surfaces that are pressed against by the brake pads.

[0021] The disc sliding portion 23 includes an inner disc portion 28, an outer disc portion 29 disposed on the outer side of the inner disc portion 28, and fins 30. The fins 30 connect the inner disc portion 28 and the outer disc portion 29 at multiple locations in the circumferential direction. The fins 30 extend radially, and the space surrounded by the inner disc portion 28, the outer disc portion 29, and the fins 30 forms an air passage 30a penetrating in the radial direction (diametrical direction). The air passage 30a is a passage that extends from an air intake port 31 formed on the radially inner side of the disc sliding portion 23 to an air exhaust port 32 formed on the radially outer side.

[0022] The hub bearing 40 is a rolling bearing (specifically, a radial ball bearing) and includes an outer ring member 50 (corresponding to the "first bearing member"), an inner ring member 60 (corresponding to the "second bearing member"), and a plurality of rolling elements 41 (specifically, balls) arranged between the outer ring member 50 and the inner ring member 60. The hub bearing 40 of this embodiment has a structure in which the rolling elements 41 are arranged in two rows in the axial direction. Note that the hub bearing 40 may also be a radial roller bearing provided with rollers as the rolling elements 41.

[0023] The inner ring member 60 includes an inner cylindrical portion 61 (corresponding to a "second cylindrical portion") extending in the axial direction, and a flange portion 62 extending radially from a first end of the inner cylindrical portion 61 in the axial direction. A shaft insertion hole 63 is formed in the inner cylindrical portion 61, penetrating it in the axial direction. A spline is formed on the inner peripheral surface of the shaft insertion hole 63. A shaft (not shown) to which rotational power of a traveling power source such as a motor is transmitted is fitted in the shaft insertion hole 63.

[0024] The outer ring member 50 has an outer cylindrical portion 51 (corresponding to a "first cylindrical portion") provided at a position facing radially outward from the inner cylindrical portion 61. A rolling element 41 is provided between the outer cylindrical portion 51 and the inner cylindrical portion 61.

[0025] The flange portion 62 is disk-shaped and extends radially outward beyond the outer cylindrical portion 51. A plurality of bolt insertion holes 64, through which hub bolts 17 for fixing the wheel 11 are inserted, are formed in the flange portion 62 and aligned in the circumferential direction. In this embodiment, five hub bolts 17 are formed and aligned in the circumferential direction. Therefore, five bolt insertion holes 64 are also formed.

[0026] The wheel unit 10 is provided with a dust cover 70, which is a heat shield. The dust cover 70 is provided on the inner side in the vehicle width direction of the hub bearing 40 and the disc sliding portion 23 of the disc rotor 21. The dust cover 70 extends radially outward beyond the outer peripheral edge of the disc sliding portion 23.

[0027] The wheel unit 10 is equipped with a detection device. The detection device is provided in the inner space of the wheel 11 and includes a target member 80 and a sensor member 100. The detection device is a device for detecting the rotational speed of the wheel consisting of the wheel 11 and tire 14, the lateral force Fy acting between the ground contact surface (ground) GL and the wheel (specifically, the tire 14), and the force acting between the ground contact surface GL and the wheel in a direction perpendicular to the ground contact surface GL (hereinafter referred to as vertical load Fz). The direction in which the lateral force acts and the direction in which the vertical load acts are perpendicular to each other. For example, the calculated rotational speed, lateral force, and vertical load are used in a control device (specifically, an ECU: Electronic Control Unit) provided in the vehicle to control the running of the vehicle, which is a moving object. The structure of the detection device will be described below.

[0028] The target member 80 is made of a metal material through which magnetic flux flows. Specifically, for example, the target member 80 is made of a paramagnetic metal material (e.g., aluminum) having a relative permeability greater than 1, or a ferromagnetic metal material (e.g., iron) having a relative permeability greater than 1. The target member 80 has an annular shape extending in the circumferential direction about the central rotation axis of the hub bearing 40. The target member 80 is provided at a position facing the sensor member 100 in the axial direction without contacting the sensor member 100. The target member 80 is fixed to, for example, the flange portion 62, and rotates integrally with the inner ring member 60.

[0029] As shown in Figures 4 and 7, the target member 80 has a portion facing the sensor member 100, in which protrusions 82, each having a flat surface 82a and projecting toward the knuckle 15 in the axial direction (i.e., toward the inside in the vehicle width direction), are formed side by side in the circumferential direction. The flat surfaces between the protrusions 82 lined up in the circumferential direction are recesses 83. As a result, the protrusions 82 and recesses 83 are alternately provided in the circumferential direction. In this embodiment, 12 pairs of protrusions 82 and recesses 83 are provided. The protrusions 82 and recesses 83 form a detection target portion 84.

[0030] 7, LCi indicates the center axis of the inner ring member 60. In this embodiment, the angle α1 formed by the axis passing through the center axis LCi and one circumferential end of the protruding portion 82 and the axis passing through the center axis LCi and the other circumferential end of the protruding portion 82 is equal to the angle α2 formed by the axis passing through the center axis LCi and one circumferential end of the recessed portion 83 and the axis passing through the center axis LCi and the other circumferential end of the recessed portion 83. Therefore, the circumferential length of the multiple protruding portions 82 and the circumferential length of the multiple recessed portions 83 are equal to each other.

[0031] Next, a configuration for fixing the wheel 11, the disc rotor 21, and the target member 80 to the flange portion 62 will be described.

[0032] As shown in Fig. 3, the disc mounting portion 18 has a bolt insertion hole 18a formed therethrough in the axial direction. With the bottom surface portion 24 and the disc mounting portion 18 overlapping the mounting surface 62b of the flange portion 62, a hub bolt 17 is inserted into the bolt insertion holes 27, 18a. A nut 35 is threaded onto the hub bolt 17, thereby fixing the disc mounting portion 18 and the disc rotor 21 to the hub bearing 40. This makes the target member 80, disc rotor 21, and inner ring member 60 coaxial, and causes the target member 80, disc rotor 21, and wheel 11 to rotate integrally.

[0033] Next, the sensor member 100 will be described.

[0034] The sensor member 100 is a so-called eddy current inductive sensor. The sensor member 100 has a flat shape with its thickness direction aligned with the axial direction. The sensor member 100 is provided in an arrangement space that is adjacent to the flange portion 62 on the inner side in the vehicle width direction and that is radially outward of the inner cylindrical portion 61 and the outer cylindrical portion 51. In the arrangement space, a detection object portion 84 of the target member 80 is provided at a position facing the sensor member 100 in the axial direction. The sensor member 100 is provided between the flange portion 62 and the hub mounting portion 52.

[0035] As shown in Figs. 6 and 8, the sensor member 100 has an arc-shaped plate surface that conforms to the detection target portion 84 when viewed from the front. As shown in Fig. 9, the sensor member 100 includes an excitation coil 110, a receiving coil, and a case member 140 that houses the excitation coil 110 and the receiving coil. In this embodiment, the receiving coils are a first receiving coil 111 and a second receiving coil 112. Each of the coils 110 to 112 is a planar coil that conforms to the plate surface of an arc-shaped substrate 116. The substrate 116 is a multi-layer substrate. Each of the coils 110 to 112 is formed by wiring patterns, vias, and the like formed on each layer of the substrate 116.

[0036] The sensor member 100 includes an excitation circuit 113 that supplies a high-frequency excitation voltage to the excitation coil 110, and a receiving circuit 114. The excitation circuit 113 and the receiving circuit 114 are mounted on a substrate 116. When an excitation voltage is supplied to the excitation coil 110, an excitation current flows through the excitation coil 110, and a voltage having the same or an equivalent frequency as the excitation voltage is induced in each of the coils 111 and 112. The receiving circuit 114 detects output voltage signals at both ends of each of the coils 111 and 112. When an excitation voltage is supplied to the excitation coil 110, the phase difference between the first output voltage signal of the first receiving coil 111 and the output voltage signal of the second receiving coil 112 is 90 degrees.

[0037] In this embodiment, the coils 110 to 112 have the same circumferential center position. The circumferential center position of each of the coils 110 to 112 is located opposite the lower end of the detection object portion 84 in the axial direction.

[0038] As shown in FIG. 8, the case member 140 includes a main body 141 on which the circuit board 116 is disposed, and a lid 142 that covers an opening 141a of the main body 141. The case member 140 is made of a non-magnetic material, such as a synthetic resin. The plate surface of the main body 141 opposite the opening 141a is a first case plate surface 144a. The surface of the lid 142 is a second case plate surface 144b. The side surface of the case member 140 that connects the first case plate surface 144a and the second case plate surface 144b is a case side surface 143. The lid 142 is provided with a connector 117 that is electrically connected to the excitation circuit 113 and the receiving circuit 114. As shown in FIG. 9, the connector 117 is electrically connected to a processing unit 119 via a cable 118. The processing unit 119 may be provided on the vehicle body or may be built into the wheel unit 10.

[0039] The processing unit 119 includes a CPU (Central Processing Unit). The functions of the processing unit 119 can be provided by software stored in a physical memory device and a computer executing the software, by software alone, by hardware alone, or by a combination of these. For example, if the microcomputer of the processing unit 119 is provided by a hardware electronic circuit, the function can be provided by a digital circuit including multiple logic circuits or an analog circuit. For example, the microcomputer executes a program stored in a non-transitory tangible storage medium serving as a storage unit of the microcomputer. The program includes, for example, a program for a load calculation process, which will be described later. A set of instructions constituting the program is executed to perform a method corresponding to the program. The storage unit is, for example, a non-volatile memory. The program stored in the storage unit can be updated via a communication network such as the Internet, for example, via OTA (Over The Air) or the like.

[0040] Next, the load calculation process will be described.

[0041] 2, when a lateral force Fy acts on the wheel, the inclination θ of the central axis LCi of the inner ring member 60 relative to the central axis of the outer ring member 50 increases. In this case, the axial distance between each of the coils 111, 112 and the detection object 84 changes, and the amplitude of the output voltage signal of each of the coils 111, 112 changes. Based on this change in amplitude, the processing unit 119 calculates the axial displacement ΔY of the detection object 84, and performs processing to calculate the lateral force Fy based on the calculated axial displacement ΔY.

[0042] On the other hand, when a vertical load Fz acts on the wheel, the central axis LCi of the inner ring member 60 is displaced in a direction perpendicular to the central axis of the outer ring member 50. As a result, the target member 80 fixed to the flange portion 62 is also displaced. In this case, the sensor member 100 is configured so that the amplitude of the output voltage signals of the first receiving coil 111 and the second receiving coil 112 changes. Based on this change in amplitude, the processing unit 119 calculates the displacement of the detection object portion 84 in a direction perpendicular to the axial direction and the vehicle length direction (hereinafter referred to as the vertical displacement ΔZ), and performs processing to calculate the vertical load Fz based on the calculated vertical displacement ΔZ.

[0043] The processing unit 119 calculates the rotation angle of the wheel based on the output signal of at least one of the first receiving coil 111 and the second receiving coil 112. The processing unit 119 calculates the rotation speed of the wheel based on the calculated rotation angle. Specifically, for example, the processing unit 119 may calculate the rotation speed based on the time differential value of the rotation angle.

[0044] The substrate 116 and the load calculation process are described in, for example, Japanese Patent Application Laid-Open No. 2023-130285.

[0045] Next, a configuration for fixing the sensor member 100 to the outer ring member 50 of the hub bearing 40 will be described with reference to Figures 3, 4, 6, 10, 11, etc.

[0046] The wheel unit 10 includes a bracket member 120 as a component for fixing the sensor member 100 to the outer ring member 50. As shown in FIGS. 10 and 11 , the bracket member 120 is made of a non-magnetic material, such as a synthetic resin or a metal material (e.g., aluminum). The bracket member 120 includes a bracket base 121 that serves as a base for the bracket member 120. The bracket base 121 is plate-shaped and has an annular shape. A circular (specifically, perfect circular) through-hole 122 is formed in the center of the bracket base 121. The through-hole 122 axially penetrates from the first plate surface 121a to the second plate surface 121b of the bracket base 121, and the outer cylindrical portion 51 is fitted into the through-hole 122.

[0047] The bracket member 120 includes a thick portion 123 and a protrusion 124 as components for attaching the sensor member 100. The thick portion 123 extends from the first plate surface 121a of the bracket base 121 toward the flange portion 62 in the axial direction. The thick portion 123 has an arc shape that extends in the circumferential direction.

[0048] The protrusions 124 extend axially from the first plate surface 121a of the bracket base 121 toward the flange portion 62. Each protrusion 124 is formed with a bolt insertion hole 126 that penetrates axially and through which a board mounting bolt 125 is inserted. Bolt insertion holes 127 that penetrate axially and through which a board mounting bolt 125 is inserted are formed in each circumferentially spaced portion of the thick-walled portion 123. Meanwhile, as shown in FIG. 8 , the main body 141 of the sensor member 100 is formed with the same number of female threaded holes 101 as the bolt insertion holes 126, 127, into which the male threads of the board mounting bolts 125 are screwed.

[0049] The female screw hole 101 of the main body 141 is aligned with the bolt insertion hole 126 of the protrusion 124 and the bolt insertion hole 127 of the thick-walled portion 123. In this aligned state, the board mounting bolt 125 is inserted into the bolt insertion holes 126 and 127 from the second plate surface 121b side of the bracket base 121, and the male thread of the board mounting bolt 125 is screwed into the female screw hole 101. As a result, both circumferential ends and a circumferential middle portion of the case member 140 are fixed to the bracket member 120 with the sensor member 100 and the bracket member 120 maintaining a predetermined relative positional relationship. In this case, the plate surface of the sensor member 100 (specifically, the board 116) and the plate surface of the bracket base 121 are parallel to each other. The sensor member 100 is supported by the protrusion 124 and the thick-walled portion 123 while being spaced apart from the first plate surface 121a of the bracket base 121.

[0050] When an excitation voltage is applied to the excitation coil 110 of the sensor member 100, a current flows through each of the coils 110-112, causing each of the coils 110-112 to generate heat. For this reason, it is desirable to provide a configuration for effectively cooling each of the coils 110-112. As shown in FIG. 3, the sensor member 100 is disposed radially inward of the air intake 31 of the disc rotor 21. Furthermore, because the sensor member 100 and the bracket base 121 are spaced apart, an air passage is formed between the sensor member 100 and the first plate surface 121a of the bracket member 120. In this case, as the disc rotor 21 rotates, airflow is generated from this air passage toward the air intake 31. As a result, the sensor member 100 can be effectively cooled.

[0051] In the bracket base 121, at a position shifted in the circumferential direction from the protrusion 124 and the thick portion 123, a bolt insertion hole 128 is formed, which penetrates from the first plate surface 121a to the second plate surface 121b and through which the bolt 16 is inserted. In this embodiment, three bolt insertion holes 128 are formed spaced apart in the circumferential direction.

[0052] The dust cover 70 includes a first wall portion 73, a connecting portion 74, and a second wall portion 75. The connecting portion 74 extends radially outward from the radially outer end portion of the first wall portion 73. The second wall portion 75 extends radially outward from the radially outer end portion of the connecting portion 74.

[0053] The first wall portion 73 of the dust cover 70 has a circular (specifically, perfect circular) through-hole 72 formed therein, which extends in a direction perpendicular to the plate surface of the first wall portion 73 and into which the outer cylindrical portion 51 is fitted. The knuckle 15 has a circular (specifically, perfect circular) through-hole 15a formed therein, which extends in the axial direction and into which the outer cylindrical portion 51 of the outer ring member 50 is fitted.

[0054] A bolt insertion hole 71 through which the bolt 16 is inserted is formed in the first wall portion 73 of the dust cover 70. A bolt insertion hole 15b through which the bolt 16 is inserted is formed in the knuckle 15.

[0055] The outer cylindrical portion 51 of the hub bearing 40 is provided with hub mounting portions 52 extending in the radial direction. The number of hub mounting portions 52 provided is the same as the number of bolt insertion holes 128. The hub mounting portions 52 are spaced apart in the circumferential direction. As shown in FIGS. 3 and 4, the hub mounting portions 52 are formed with female threaded holes 52a that pass through in the axial direction and into which the bolts 16 are screwed. The hub mounting portions 52 are formed with flat surfaces 52b that extend in a direction perpendicular to the axial direction.

[0056] With the sensor member 100 attached, the first plate surface 121a of the bracket member 120 is brought into contact (specifically, surface contact) with the flat surface 52b of the hub mounting portion 52, and the dust cover 70 and the knuckle 15 are placed on top of the bracket member 120. In this state, the bolt 16 is inserted into the bolt insertion holes 71, 128, and the male thread of the bolt 16 is screwed into the female threaded hole 52a of the hub mounting portion 52. This fixes the bracket member 120, outer ring member 50, and dust cover 70 so that they cannot be displaced relative to the knuckle 15. The bracket member 120 and the dust cover 70 are formed with cable insertion holes 129, 78 through which the cable 118 connected to the connector 117 of the sensor member 100 is inserted (see FIGS. 4 and 5, etc.).

[0057] The bracket member 120 can determine the relative positions of the sensor member 100 and the detection target portion 84. For example, by adjusting the axial length dimensions of the thick-walled portion 123 and the protrusion 124 of the bracket member 120 at the time of design, it is possible to adjust the gap between the flat surface 82a of the protrusion 82 and the first case plate surface 144a of the sensor member 100. As a result, it is possible to reduce the effect of the shape of the hub bearing 40 on the mounting mode of the sensor member 100 for aligning the first case plate surface 144a with the detection target portion 84. This minimizes changes to the shape of the sensor member 100, even if the shape of the hub bearing changes depending on the type of vehicle, for example.

[0058] Incidentally, the temperature of each of the coils 110-112 rises as a result of current flowing through the coils 110-112. The temperature of each of the coils 110-112 also rises due to heat generated when the brake pad is pressed against the disc sliding portion 23. The temperature rise of each of the coils 110-112 affects the voltage signals output from the receiving coils 111, 112, which may reduce the accuracy of detecting displacement or force.

[0059] Therefore, the wheel unit 10 of this embodiment is provided with a configuration for suppressing the temperature rise of each of the coils 110 to 112. This configuration will be described below.

[0060] 10 and 11, the wheel unit 10 includes a cooling pipe 150. The cooling pipe 150 is a copper pipe. The cooling pipe 150 includes an inlet pipe 151, an outlet pipe 152, and an intermediate pipe 153 that connects the inlet pipe 151 and the outlet pipe 152.

[0061] 10, 5, etc., inlet through-holes 131, 76, through which the inlet piping 151 is inserted, are formed in the bracket base 121 and the first wall portion 73 of the dust cover 70. Outlet through-holes 132, 77, 15c, through which the outlet piping 152 is inserted, are formed in the bracket base 121, the first wall portion 73, and the knuckle 15. The intermediate piping 153 is disposed between the outer cylindrical portion 51 and the thick-walled portion 123 of the outer ring member 50, and extends in the circumferential direction. As a result, the intermediate piping 153 is disposed in a position adjacent to the sensor member 100.

[0062] Cooling water, which is a liquid cooling fluid, flows in through inlet pipe 151 and then flows through intermediate pipe 153. The cooling water that has flowed through intermediate pipe 153 is then discharged from outlet pipe 152. This allows the bracket member 120 to be cooled, and ultimately makes it possible to suppress a rise in temperature of the exciting coil 110 and the receiving coils 111 and 112.

[0063] The intermediate pipe 153 is disposed between the outer cylindrical portion 51 and the thick-walled portion 123 of the outer ring member 50, and extends in the circumferential direction. This makes it difficult for heat generated in the hub bearing 40 as the inner cylindrical portion 61 rotates to be transmitted to the thick-walled portion 123. As a result, the temperature rise of the sensor member 100 can be suppressed.

[0064] The disc rotor 21 is disposed radially outward of the bracket member 120. Therefore, there is little space radially outward of the bracket member 120. Therefore, the inlet pipe 151 and the outlet pipe 152 extend axially toward the knuckle side of the bracket member 120. This ensures a flow path for the cooling water to flow through the intermediate pipe 153.

[0065] 12 shows an example of a configuration in which cooling water is supplied to the inlet pipe 151 and the cooling water discharged from the outlet pipe 152 is received. FIG. 12 shows a cooling device that cools various devices mounted on a vehicle.

[0066] The vehicle includes, as various devices, an inverter 200, a rotating electric machine 201, and a storage battery 202 that connects the inverter 200 and the rotating electric machine 201. The inverter 200 is switched to drive and rotate the wheels of the vehicle.

[0067] The cooling device includes a main circulation path 203 through which coolant circulates, an electric water pump 204, a radiator 205, and an electric fan 206. Water pump 204 is powered and driven to circulate the coolant. In the example shown in Fig. 12, an inverter 200, a rotating electric machine 201, and a storage battery 202 are arranged in this order downstream of water pump 204 in main circulation path 203. Note that the arrangement order of the various devices in main circulation path 203 is not limited to the order shown in Fig. 12.

[0068] A radiator 205 is provided in main circulation path 203 between water pump 204 and storage battery 202. Radiator 205 cools the coolant flowing in via main circulation path 203 and supplies the cooled water to water pump 204. The coolant flowing into radiator 205 is cooled by wind blown against radiator 205 as the vehicle travels and wind blown against radiator 205 by rotating fan 206.

[0069] A first branch path 207 and a second branch path 208 are connected to a portion of the main circulation path 203 between the water pump 204 and the radiator 205. The first branch path 207 is connected to the inlet pipe 151. The second branch path 208 is connected to the outlet pipe 152. As a result, a portion of the coolant circulating through the main circulation path 203 flows through the first branch path 207, the inlet pipe 151, the intermediate pipe 153, the outlet pipe 152, and the second branch path 208. As a result, the bracket member 120 is cooled, and ultimately the coils 110-112 are cooled.

[0070] Second Embodiment The second embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. The bracket member of this embodiment has a structure in which a cooling water flow path is formed within the thick-walled portion. This structure will be described below with reference to Figures 13 to 18.

[0071] Similar to the bracket member 120 of the first embodiment, the bracket member 220 includes a bracket base 221 and a protrusion 224. The bracket base 221 includes a first plate surface 221a and a second plate surface 221b. In the bracket member 220, the through hole 222, the bolt insertion holes 226, 227, 228, and the cable insertion hole 229 correspond to the through hole 122, the bolt insertion holes 126, 127, 128, and the cable insertion hole 129 of the first embodiment.

[0072] The bracket member 220 includes a thick portion 290. The thick portion 290 has an arc shape extending in the circumferential direction. A recess 291 that is recessed toward the sensor member 100 in the axial direction is formed in the portion of the thick portion 290 on the knuckle 15 side. The recess 291 opens toward the knuckle 15 side. An interference avoidance portion 292 that is recessed radially inward is formed in a circumferential intermediate portion of the thick portion 290. The interference avoidance portion 292 is provided to avoid interference between the connector 117 and the thick portion 290.

[0073] The wheel unit 10 has a configuration for fixing the thick portion 290 to the bracket base 221. More specifically, bolt insertion holes 293 are formed at both circumferential ends of the thick portion 290, which penetrate in the axial direction and through which the component mounting bolt 280 is inserted. The bracket base 221 is formed with a female screw hole 241 into which the male screw of the component mounting bolt 280 is screwed.

[0074] The wheel unit 10 is provided with a seal member 270 that prevents cooling water leakage from between the thick portion 290 and the bracket base 221. The seal member 270 extends along the periphery of the opening of the recess 291 and is provided with an annular seal body 271. Bolt insertion holes 272 corresponding to the bolt insertion holes 293 and the female screw hole 241 are formed at both circumferential ends of the seal body 271.

[0075] With the seal member 270 sandwiched between the thick portion 290 and the bracket base 221, the component mounting bolt 280 is inserted into the bolt insertion holes 293, 272, and the male thread of the component mounting bolt 280 is screwed into the female threaded hole 241. This fixes the thick portion 290 to the bracket base 221. The space surrounded by the recess 291 of the thick portion 290 and the bracket base 221 forms a bracket flow path 295 (see FIG. 16 ).

[0076] The wheel unit 10 is equipped with an inlet pipe 251 and an outlet pipe 252 as cooling channels. The inlet pipe 251 supplies cooling water to the bracket channel 295. The outlet pipe 252 discharges cooling water from the bracket channel 295. An inlet through-hole 231 penetrating in the axial direction is formed in the bracket base 221 at a position facing one circumferential end of the recess 291 of the thick-walled portion 290. An outlet through-hole 232 penetrating in the axial direction is formed in the bracket base 221 at a position facing the other circumferential end of the recess 291 of the thick-walled portion 290.

[0077] The tip end of the inlet pipe 251 is a reduced diameter section 251a whose outer diameter is smaller than that of the base end side. An annular seal member 261 (for example, a gasket or an O-ring) is inserted into the reduced diameter section 251a, and the reduced diameter section 251a is fitted into the inlet through-hole 231. As shown in Fig. 14, an inlet through-hole 76 through which the inlet pipe 251 is inserted is formed in the first wall section 73 of the dust cover 70.

[0078] The tip end of the outlet pipe 252 is formed as a reduced diameter section 252a whose outer diameter is smaller than that of the base end side. The reduced diameter section 252a is fitted into the outlet through-hole 232 with an annular seal member 262 (e.g., a gasket or an O-ring) inserted into the reduced diameter section 252a. As a result, for example, cooling water supplied from the main circulation path 203 in FIG. 12 flows into the bracket flow path 295 via the first branch path 207 and the inlet pipe 251. The flowing cooling water is returned to the main circulation path 203 via the outlet pipe 252 and the second branch path 208. As shown in FIG. 14, an outlet through-hole 77 through which the outlet pipe 252 is inserted is formed in the first wall portion 73 of the dust cover 70.

[0079] Next, a description will be given of the structure for fixing the sensor member 100 to the bracket member 220. The thick portion 290 and the seal member 270 are formed with bolt insertion holes 294, 273 through which the board mounting bolts 125 are inserted.

[0080] The female screw hole 101 of the main body 141 is aligned with the bolt insertion hole 226 of the protrusion 224, the bolt insertion hole 294 of the thick-walled portion 290, and the bolt insertion hole 273 of the seal member 270. In this aligned state, the board mounting bolt 125 is inserted into the bolt insertion holes 226, 227, 273, and 294 from the second plate surface 221b side of the bracket base 221, and the male thread of the board mounting bolt 125 is screwed into the female screw hole 101. As a result, the case member 140 is fixed to the bracket member 220 with the sensor member 100 and the bracket member 220 maintaining a predetermined relative positional relationship. The second case plate surface 144b of the sensor member 100 abuts against the thick-walled portion 290.

[0081] According to the present embodiment described above, it is possible to effectively cool the bracket member 220 from the inside. This makes it possible to enhance the cooling effect of the sensor member 100, and in turn makes it possible to effectively suppress the temperature rise of each of the coils 110-112.

[0082] 16 is a cross-sectional view taken along line 16-16 in FIG. 15. In this embodiment, a side recess 145 recessed in the axial direction is formed in a case side surface portion 143 of the sensor member 100. The space surrounded by the side recess 145 and the lid portion 142 functions as a heat insulating layer. As a result, the case side surface portion 143 has a lower thermal conductivity than the lid portion 142. This makes it possible to suppress a temperature rise in the sensor member 100 caused by heat from the disc rotor 21.

[0083] The lid portion 142 that abuts against the thick portion 290 has a higher thermal conductivity than the case side portion 143. This allows heat to be effectively transferred from the lid portion 142 to the cooling water flowing through the bracket flow path 295. As a result, the effect of suppressing the temperature rise of the sensor member 100 can be improved.

[0084] <Modification of the second embodiment> Instead of or in addition to the case side portion 143 shown in FIG. 16, a space that functions as a heat insulating layer may be formed in the main body portion 141 (specifically, the upper part of the main body portion 141 in FIG. 16). 19, a case recess 146 recessed in the axial direction may be formed on the first case plate surface 144a side of the main body 141, and a heat insulating member 147 may be provided in the case recess 146. For example, the heat insulating member 147 may be fixed to the case recess 146 with an adhesive. This can enhance the effect of suppressing the temperature rise of the sensor member 100.

[0085] Third Embodiment The third embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. This embodiment has a structure in which a cooling water flow path is formed within the sensor member 100. This structure will be described below with reference to Figures 20 to 27.

[0086] Similar to the bracket member 120 of the first embodiment, the bracket member 320 includes a bracket base 321. The bracket base 321 includes a first plate surface 321a and a second plate surface 321b. In the bracket member 320, the through hole 322, the bolt insertion hole 328, and the cable insertion hole 329 correspond to the through hole 122, the bolt insertion hole 128, and the cable insertion hole 129 of the first embodiment.

[0087] The bracket member 320 has a first thick portion 390 and a second thick portion 490 to which the sensor member 100 is fixed. The first thick portion 390 and the second thick portion 490 are spaced apart in the circumferential direction.

[0088] The first thick portion 390 has an arc shape extending in the circumferential direction. A recess 391 recessed toward the sensor member 100 in the axial direction is formed in a portion of the first thick portion 390 on the knuckle 15 side. The recess 391 opens toward the knuckle 15 side. As in the second embodiment, an interference avoidance portion 392 recessed radially inward is formed in a circumferential intermediate portion of the first thick portion 390.

[0089] The wheel unit 10 has a configuration for fixing the first thick portion 390 to the bracket base 321. More specifically, first bolt insertion holes 393 are formed at both circumferential ends of the first thick portion 390, which penetrate in the axial direction and through which the first component mounting bolt 380 is inserted. The bracket base 321 is formed with a first female screw hole 341 into which the male thread of the first component mounting bolt 380 is screwed.

[0090] The wheel unit 10 is provided with a first seal member 370 that prevents cooling water leakage from between the first thick portion 390 and the bracket base 321. The first seal member 370 extends along the periphery of the opening of the recess 391 and is provided with an annular seal body 371. First bolt insertion holes 372 corresponding to the first bolt insertion hole 393 and the first female screw hole 341 are formed at both circumferential ends of the seal body 371.

[0091] With the first seal member 370 sandwiched between the first thick portion 390 and the bracket base 321, the first component mounting bolt 380 is inserted into the first bolt insertion holes 393, 372, and the male thread of the first component mounting bolt 380 is screwed into the first female threaded hole 341. This fixes the first thick portion 390 to the bracket base 321. As shown in FIG. 27 , the space surrounded by the recess 391 of the first thick portion 390 and the first plate surface 321a of the bracket base 321 defines a first bracket flow path 395. The first bracket flow path 395 extends circumferentially.

[0092] 22, a recess 491 recessed toward the sensor member 100 in the axial direction is formed in a portion of the second thick portion 490 on the knuckle 15 side. The recess 491 is open toward the knuckle 15 side.

[0093] The wheel unit 10 has a configuration for fixing the second thick portion 490 to the bracket base 321. More specifically, second bolt insertion holes 493 are formed at both circumferential ends of the second thick portion 490, which penetrate in the axial direction and through which the second component mounting bolt 480 is inserted. The bracket base 321 is formed with second female screw holes 342 into which the male threads of the second component mounting bolts 480 are screwed.

[0094] The wheel unit 10 is provided with a second seal member 470 that prevents cooling water leakage from between the second thick portion 490 and the bracket base 321. The second seal member 470 extends along the periphery of the opening of the recess 491 and is provided with an annular seal body 471. Second bolt insertion holes 472 corresponding to the second bolt insertion hole 493 and the second female screw hole 342 are formed at both circumferential ends of the seal body 471.

[0095] With the second seal member 470 sandwiched between the second thick portion 490 and the bracket base 321, the second component mounting bolt 480 is inserted into the second bolt insertion holes 493, 472, and the male thread of the second component mounting bolt 480 is screwed into the second female threaded hole 342. This fixes the second thick portion 490 to the bracket base 321. As shown in FIG. 27 , a space surrounded by the recess 491 of the second thick portion 490 and the first plate surface 321a of the bracket base 321 defines a second bracket flow path 495.

[0096] An inlet through-hole 331 penetrating in the axial direction is formed in bracket base 321 at a position facing recess 391 of first thick portion 390. An outlet through-hole 332 penetrating in the axial direction is formed in bracket base 321 at a position facing recess 491 of second thick portion 490.

[0097] The wheel unit 10 includes an inlet pipe 351 and an outlet pipe 352. The tip end of the inlet pipe 351 is formed as a reduced diameter section 351a whose outer diameter is smaller than that of the base end side. The reduced diameter section 351a is fitted into the inlet through-hole 331 with an annular seal member 361 (for example, a gasket or O-ring) inserted through it.

[0098] The tip end of the outlet pipe 352 is a reduced diameter section 352a whose outer diameter is smaller than that of the base end side. The reduced diameter section 352a is fitted into the outlet through-hole 332 with an annular sealing member 362 (for example, a gasket or an O-ring) inserted through it.

[0099] Next, the flow path within the case member 140 that constitutes the sensor member 100 will be described.

[0100] As shown in FIG. 27, a flow path portion 148 that is recessed in the axial direction and extends in the circumferential direction is formed in a portion of the main body portion 141 on the side of the first case plate surface 144a. As shown in FIGS. 27 and 24, the case member 140 includes a cover portion 149 that covers the flow path portion 148. The cover portion 149 is made of a non-magnetic material, such as a synthetic resin. The cover portion 149 is fixed to the main body portion 141. The space that is surrounded by the flow path portion 148 and the cover portion 149 and extends in the circumferential direction serves as an internal case flow path 600 (see FIG. 27). In this embodiment, the internal case flow path 600 is provided in the case member 140 closer to the target member 80 than the substrate 116 in the axial direction.

[0101] A first flow path portion 601 extending in the axial direction is provided at one circumferential end portion of the main body portion 141. A second flow path portion 602 extending in the axial direction is provided at the other circumferential end portion of the main body portion 141. The first flow path portion 601 is connected to one circumferential end portion of the case internal flow path 600, and the second flow path portion 602 is connected to the other circumferential end portion of the case internal flow path 600.

[0102] 23, 25, and 27, a first fitting hole 396 into which a first flow path portion 601 is fitted is formed in the first thick-walled portion 390. A second fitting hole 496 into which a second flow path portion 602 is fitted is formed in the second thick-walled portion 490. Note that the first flow path portion 601 is fitted into the first fitting hole 396 with an annular first case side seal member 611 (e.g., a gasket or an O-ring) inserted into the first flow path portion 601. Furthermore, the second flow path portion 602 is fitted into the second fitting hole 496 with an annular second case side seal member 612 (e.g., a gasket or an O-ring) inserted into the second flow path portion 602.

[0103] In this embodiment, the inlet pipe 351, the first bracket flow path 395, and the first flow path portion 601 correspond to an "inlet flow path portion." Also, the outlet pipe 352, the second bracket flow path 495, and the second flow path portion 602 correspond to an "outlet flow path portion."

[0104] Next, a configuration for fixing the sensor member 100 to the bracket member 220 will be described.

[0105] 22, first bolt insertion holes 394, 373, through which first board mounting bolt 125a is inserted, are formed in first thick portion 390 and first seal member 370. A first bolt insertion hole 343, through which first board mounting bolt 125a is inserted, is formed in bracket base 321.

[0106] Second thick portion 490 and second seal member 470 have second bolt insertion holes 494, 473 through which second board mounting bolt 125b is inserted. Bracket base 321 has second bolt insertion hole 344 through which second board mounting bolt 125b is inserted.

[0107] The female screw hole 101 of the main body 141 is aligned with the first bolt insertion hole 394 of the first thick portion 390 and the first bolt insertion hole 373 of the first seal member 370. In this aligned state, the first board mounting bolt 125a is inserted into the first bolt insertion holes 343, 373, 394 from the second plate surface 321b side of the bracket base 321, and the male thread of the first board mounting bolt 125a is screwed into the female screw hole 101.

[0108] Furthermore, the female screw hole 101 of the main body 141 is aligned with the second bolt insertion hole 494 of the second thick portion 490 and the second bolt insertion hole 473 of the second seal member 470. In this aligned state, the second board mounting bolt 125b is inserted into the second bolt insertion holes 344, 473, 494 from the second plate surface 321b side of the bracket base 321, and the male thread of the second board mounting bolt 125b is screwed into the female screw hole 101.

[0109] As a result, the case member 140 is fixed to the bracket member 320 while maintaining a predetermined relative positional relationship between the sensor member 100 and the bracket member 320. The second case plate surface 144b of the sensor member 100 abuts against the first and second thick portions 390, 490.

[0110] 12 flows into the case internal flow path 600 via the first branch path 207, the inlet pipe 351, the first bracket flow path 395, and the first flow path portion 601. The flowing cooling water is returned to the main circulation path 203 via the second flow path portion 602, the second bracket flow path 495, the outlet pipe 352, and the second branch path 208. This allows the sensor member 100 to be effectively cooled, and the temperature rise of each of the coils 110-112 to be suppressed.

[0111] <Other embodiments> The above-described embodiments may be modified as follows.

[0112] 28, the sensor member 100 may be fixed to a sensor mounting portion 53 provided on the outer cylindrical portion 51 of the hub bearing 40. Specifically, the sensor member 100 may be fixed to the sensor mounting portion 53 by a mounting hole 53a and a bolt formed in the sensor mounting portion 53. In this case, for example, the cooling structure described in the first embodiment or a cooling structure in which a cooling water flow path is provided within the sensor member 100 as described in the fourth embodiment may be employed.

[0113] The cooling structure is not limited to a water-cooled structure using cooling water, but may be an oil-cooled structure. In this case, for example, the cooling flow path of the bracket member or the sensor member may be connected to the brake oil pipe that constitutes the brake device 20.

[0114] In the target member 80, a hole that passes through the target member 80 in the axial direction may be formed instead of the recess 83. The hole is a portion that is recessed toward the flange portion 62 side relative to the protrusion 82.

[0115] The hub bearing is not limited to an inner ring rotation type, and may be an outer ring rotation type. Specifically, the inner ring axial member (corresponding to the "first bearing member") constituting the outer ring rotation type hub bearing has an inner cylindrical portion (corresponding to the "first cylindrical portion") extending in the axial direction and is fixed to the knuckle 15. The outer ring axial member (corresponding to the "second bearing member") constituting the hub bearing has an outer cylindrical portion (corresponding to the "second cylindrical portion") provided radially outside the inner cylindrical portion, and a flange portion extending radially from the outer cylindrical portion and to which the wheel is fixed.

[0116] The circumferential center positions of the first and second receiving coils 111, 112 may be provided at positions axially facing the right or left end of the target member 80, rather than at positions axially facing the lower or upper end of the target member 80. In this case, the sensor member 100 and the processing unit 119 can calculate the force acting between the ground contact surface GL and the wheel in the vehicle length direction (hereinafter referred to as the longitudinal load Fx) instead of the vertical load Fz. The direction in which the lateral force Fy acts is perpendicular to the direction in which the longitudinal load Fx acts. The longitudinal load Fx is used by the control device to control the running of the vehicle.

[0117] The disc rotor is not limited to a ventilated disc, but may be, for example, a solid disc made of a single circular plate.

[0118] The mechanical device to which the detection device can be applied is not limited to a wheel unit, but may also be, for example, an aircraft equipped with a propeller as a rotating body, a ship equipped with a screw as a rotating body, an internal combustion engine equipped with a crankshaft as a rotating body, or a generator equipped with a turbine as a rotating body.

[0119] Furthermore, the rotating body is not limited to being used with the axial direction of the rotating body being horizontal, but may also be used with the axial direction being in a direction other than horizontal (for example, up and down). [Explanation of symbols]

[0120] 10...wheel unit, 15...knuckle, 17...hub bolt, 40...hub bearing, 80...target member, 100...sensor member, 110...excitation coil, 111, 112...receiving coils, 120...bracket member, 151...inlet piping, 152...outlet piping, 153...intermediate piping.

Claims

1. A detection device applied to a mechanical device (10), The mechanical device is A rotating body (11, 14), a hub bearing (40) that rotatably supports the rotating body relative to a base portion (15); Equipped with The hub bearing is a first bearing member (50) having a first cylindrical portion (51) extending in an axial direction that is the direction of the rotational center axis of the hub bearing and fixed to the base portion; a second bearing member (60) having a second cylindrical portion (61) provided at a position facing the first cylindrical portion in a radial direction perpendicular to the axial direction, and a flange portion (62) extending radially outward from the second cylindrical portion; a rolling element (41) provided between the first cylindrical portion and the second cylindrical portion; the second bearing member is rotatably supported relative to the base portion, a sensor member (100) provided at a position shifted toward the base portion relative to the flange portion in the axial direction; a detection target portion (84) that is provided in a portion of the flange portion that faces the sensor member in the axial direction and has an annular shape that extends in a circumferential direction of the second cylindrical portion; Equipped with The detection target portion is provided with convex portions (82) that protrude toward the base portion in the axial direction and portions (83) that recede toward the opposite side of the base portion from the convex portions in the axial direction, alternately in the circumferential direction, The sensor member an excitation coil (110) to which an excitation voltage is supplied; a receiving coil (111, 112) that induces a voltage when an excitation voltage is supplied to the exciting coil and outputs a voltage signal corresponding to the relative displacement of the detection target portion with respect to the receiving coil; and A detection device comprising a cooling flow path (150-152, 295, 351, 352, 395, 495, 600-602) through which a liquid cooling fluid flows to cool the excitation coil and the receiving coil.

2. a bracket member (120, 220, 320) to which the sensor member is fixed and which is fixed to the base portion; the bracket member is disposed between the base portion and the detection target portion in the axial direction, The detection device according to claim 1 , wherein the sensor member is fixed to a portion of the bracket member that faces the detection target in the axial direction.

3. The sensor member has a case member (140) that houses the excitation coil and the receiving coil, The bracket member (120) a bracket base (121) disposed radially outward relative to an outer cylindrical portion (51), which is a cylindrical portion located radially outward of the first cylindrical portion and the second cylindrical portion, and extending along the circumferential direction; a thick portion (123) extending from the bracket base toward the flange portion in the axial direction; and The case member has a first case plate surface (144a) and a second case plate surface (144b) which is the back surface of the first case plate surface, the case member is fixed to the thick-walled portion in a state in which the first case plate surface faces the detection target and the second case plate surface is in contact with the thick-walled portion, The detection device of claim 2 , wherein the cooling passage comprises a cooling pipe (150) disposed between the outer cylindrical portion and the thickened portion.

4. The sensor member has a case member (140) that houses the excitation coil and the receiving coil, The bracket member is a bracket base (221) disposed radially outward relative to an outer cylindrical portion (51), which is a cylindrical portion located radially outward of the first cylindrical portion and the second cylindrical portion, and extending along the circumferential direction; a thick portion (223) extending from the bracket base toward the flange portion in the axial direction; and The case member has a first case plate surface (144a) and a second case plate surface (144b) which is the back surface of the first case plate surface, the case member is fixed to the thick-walled portion in a state in which the first case plate surface faces the detection target and the second case plate surface is in contact with the thick-walled portion, The thick portion extends along the circumferential direction, The cooling channel comprises: a bracket flow path (295) formed within the thickened portion and extending in the circumferential direction; an inlet pipe (151) connected to the bracket flow passage and supplying the cooling fluid to the bracket flow passage; an outlet pipe (152) connected to a portion of the bracket flow path that is shifted in the circumferential direction with respect to a connection portion with the inlet pipe, and serving as an outlet for the cooling fluid; The detection device of claim 2 , comprising:

5. The case member has a case side surface portion (143) that connects the first case plate surface and the second case plate surface, The detection device according to claim 3 , wherein a portion of the case member on the second case plate surface side has a higher thermal conductivity than the case side surface portion.

6. The sensor member has a case member (140) that houses the excitation coil and the receiving coil, The case member extends along the circumferential direction, The cooling channel comprises: a case internal flow path (600) formed in the case member and extending in the circumferential direction; an inlet flow path portion (351, 395, 601) connected to the case internal flow path and supplying the cooling fluid to the case internal flow path; an outlet flow path portion (352, 495, 602) connected to a portion of the case internal flow path that is shifted in the circumferential direction with respect to a connection portion with the inlet flow path portion, and serving as an outlet for the cooling fluid; The detection device of claim 1 , comprising:

7. The mechanical device is a wheel unit (10) having vehicle wheels (11, 14) as the rotating bodies, The base portion is a knuckle (15) of the vehicle, The wheel unit includes a disk rotor (21) extending in the circumferential direction around the central axis of rotation, The disk rotor is a cylindrical disk peripheral wall portion (25) extending in the axial direction on the radially outer side of the flange portion and the sensor member; an annular disk sliding portion (23) extending radially outward from an end portion of the disk peripheral wall portion in the axial direction; The detection device according to any one of claims 1 to 4 and 6, comprising:

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