Detection device

Abstract

To provide a detection device capable of protecting a detection object part from foreign matter.SOLUTION: The detection device includes a sensor substrate 100 and a target member 80. The sensor substrate 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 includes a base annular portion 81 having an annular shape and a peripheral wall portion 86. The base annular portion 81 is provided with convex portions 82 and concave portions alternately in the circumferential direction. The convex portion 82 and the concave portion constitute a detection target portion. The peripheral wall portion 86 extends from the outer peripheral edge portion of the base annular portion 81 toward the knuckle 15 in the axial direction to a position where the peripheral wall portion 86 covers the convex portion 82 from the outside in the radial direction.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 wheel unit including a vehicle wheel and a hub bearing that rotatably supports the wheel relative to the vehicle knuckle. 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 extending in the axial direction, which is the direction of the rotational center axis of the hub bearing, and is fixed to the knuckle. The second bearing member has 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. The rolling elements are provided between the first cylindrical portion and the second cylindrical portion.

[0005] The detection device includes a sensor board and a target member for detecting a force acting on the wheel. The sensor board is provided at a position offset toward the knuckle from the flange portion in the axial direction. The target member has an annular shape that extends circumferentially around the rotational center axis of the second cylindrical portion.

[0006] The portion of the target member facing the sensor board in the axial direction has convex portions that protrude toward the knuckle in the axial direction and portions that recede toward the flange portion in the axial direction from the convex portions, alternately provided in the circumferential direction. The convex portions and concave portions form a detection target portion.

[0007] There is a concern that foreign matter (e.g., sand) may get into the space where the detection object and the sensor board are arranged from the radial outside of the target member, and if foreign matter gets in, there is a concern that the detection object may be damaged.

[0008] A primary object of the present disclosure is to provide a detection device that can protect a detection target from foreign matter. [Means for solving the problem]

[0009] The present disclosure provides a vehicle wheel; a hub bearing that rotatably supports the wheel relative to a knuckle of the vehicle; A detection device applied to a wheel unit comprising: 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 knuckle; 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 knuckle, a sensor board provided at a position shifted toward the knuckle with respect to the flange portion in the axial direction; a target member having a base annular portion extending in a circumferential direction of the second cylindrical portion around the central axis of rotation and forming an annular shape, and a peripheral wall portion; Equipped with The portion of the base annular portion that faces the sensor board in the axial direction is formed with a detection target portion in which convex portions that protrude toward the knuckle in the axial direction and portions that recede toward the flange portion in the axial direction relative to the convex portions are alternately arranged in the circumferential direction.

[0010] In the present disclosure, the peripheral wall portion extends in the axial direction from the outer peripheral edge portion of the base annular portion toward the knuckle side, at least to a position where it covers the protrusion from the outside in the radial direction.

[0011] This makes it difficult for foreign matter to enter the space in which the detection target is disposed, and the detection target can be protected from foreign matter. [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. [Figure 6] FIG. [Figure 7] FIG. 10 is a view of the target member as seen from the knuckle side. [Figure 8] FIG. 3 is a view of the target member as seen from the flange side. [Figure 9] FIG. 2 is a diagram showing the electrical configuration of a sensor substrate and a processing unit. [Figure 10] FIG. 10 is a view of the bracket member from the knuckle side. [Figure 11] FIG. 10 is a view of the bracket member as seen from the flange portion side. [Figure 12] FIG. [Figure 13] FIG. 10 is a partially enlarged view of a wheel unit according to a second embodiment. [Figure 14]FIG. 10 is a partially enlarged view of a wheel unit according to a modified example of the second embodiment. [Figure 15] FIG. 11 is a partial enlarged view of a wheel unit according to a third embodiment. [Figure 16] FIG. [Figure 17] FIG. 10 is a perspective view of a target member according to a fourth embodiment. [Figure 18] FIG. 11 is a partially enlarged view of a wheel unit according to a fifth embodiment. [Figure 19] FIG. [Figure 20] FIG. 13 is a partial enlarged view of a wheel unit according to a sixth embodiment. [Figure 21] FIG. 10 is a view of the bracket member from the knuckle side. [Figure 22] Cross-sectional view taken along line 22-22 in Figure 21. [Figure 23] FIG. 13 is a partially enlarged view of a wheel unit according to a seventh 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 5. 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. Figures 4 and 5 are exploded perspective views of the wheel unit 10.

[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. 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 holes 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, into 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, for example, as shown in FIG. 5, five hub bolts 17 are formed 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 substrate 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 orthogonal. 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 substrate 100 in the axial direction without contacting the sensor substrate 100.

[0029] As shown in Figures 6 and 7, the target member 80 includes a base annular portion 81 that extends circumferentially around the rotational center axis of the inner cylindrical portion 61 and has an annular shape. A portion of the base annular portion 81 that faces the sensor board 100 in the axial direction has convex portions 82 that protrude axially toward the knuckle 15 (i.e., toward the inside in the vehicle width direction) and have flat surfaces that are aligned in the circumferential direction. The flat surfaces between the convex portions 82 aligned in the circumferential direction are recessed portions 83. Thus, the convex portions 82 and the recessed portions 83 are alternately arranged in the circumferential direction. In this embodiment, 12 pairs of convex portions 82 and recessed portions 83 are provided. The convex portions 82 and the recessed portions 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 target member 80 to the flange portion 62 will be described.

[0032] As shown in Figure 8, an interference avoidance portion 85 recessed toward the convex portion 82 is formed on the portion of the base annular portion 81 opposite the portion where the convex portion 82 is formed. The interference avoidance portion 85 is configured to avoid interference with the head of the hub bolt 17. The same number of interference avoidance portions 85 as the number of hub bolts 17 are formed and lined up in the circumferential direction. As shown in Figures 3 and 4, the base annular portion 81 is fixed to the inner ring member 60 of the hub bearing 40 in a state of contact with the flange portion 62. The target member 80 is provided radially inward of the disc circumferential wall portion 25 that constitutes the disc rotor 21.

[0033] Next, a configuration for fixing the wheel 11 and the disc rotor 21 to the flange portion 62 will be described.

[0034] 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.

[0035] Next, the sensor substrate 100 will be described.

[0036] The sensor board 100 is a so-called eddy current inductive sensor. The sensor board 100 is disposed such that its plate surface extends in the vertical direction. The sensor board 100 is disposed in an arrangement space that is adjacent to the flange portion 62 on the inner side in the vehicle width direction and radially outward of the inner cylindrical portion 61 and the outer cylindrical portion 51. In the arrangement space, the detection object portion 84 of the target member 80 is disposed at a position axially opposite the sensor board 100. In this embodiment, the sensor board 100 is disposed at a position axially opposite the lower end of the detection object portion 84. The sensor board 100 is disposed between the flange portion 62 and the hub mounting portion 52. The sensor board 100 may be disposed, for example, at a position axially opposite the upper end of the detection object portion 84.

[0037] The sensor substrate 100 has an arc shape that fits the detection target portion 84. As shown in FIG. 9 , the sensor substrate 100 includes an excitation coil 110 and a 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 fits along the plate surface of the sensor substrate 100. The sensor substrate 100 is a multi-layer substrate. Each of the coils 110 to 112 is formed by wiring patterns, vias, etc., formed on each layer of the sensor substrate 100.

[0038] The sensor substrate 100 includes an excitation circuit 113 that supplies a high-frequency excitation voltage to the excitation coil 110, and a receiving circuit 114. 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 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. In this embodiment, the coils 110 to 112 have the same circumferential center position. Furthermore, the circumferential center positions of the coils 110 to 112 are located opposite the lower end of the detection target portion 84 in the axial direction.

[0039] The sensor board 100 is provided with a connector 115 electrically connected to the excitation circuit 113 and the receiving circuit 114. The connector 115 is electrically connected to a processing unit 117 via a cable 116. The processing unit 117 may be provided on the vehicle body or may be built into the wheel unit 10.

[0040] The processing unit 117 includes a CPU (Central Processing Unit). The functions of the processing unit 117 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 117 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.

[0041] Next, the load calculation process will be described.

[0042] 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 117 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.

[0043] 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 board 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 117 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.

[0044] The processing unit 117 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 117 calculates the rotation speed of the wheel based on the calculated rotation angle. Specifically, for example, the processing unit 117 may calculate the rotation speed based on the time differential value of the rotation angle.

[0045] The sensor substrate 100 and the load calculation process are described in, for example, Japanese Patent Application Laid-Open No. 2023-130285.

[0046] Next, a configuration for fixing the sensor board 100 to the outer ring member 50 of the hub bearing 40 will be described with reference to FIGS. 2 to 5 and 10 to 12. FIG.

[0047] The wheel unit 10 includes a bracket member 120 as a component for fixing the sensor board 100 to the outer ring member 50. The bracket member 120 is plate-shaped and annular. The bracket member 120 is made of, for example, synthetic resin or a metal material (e.g., aluminum). A circular (specifically, perfect circular) through-hole 122 is formed in the center of the bracket member 120. The through-hole 122 penetrates in the axial direction from the first plate surface 121a to the second plate surface 121b of the bracket member 120, and the outer cylindrical portion 51 is fitted into the through-hole 122.

[0048] A protrusion 130 (corresponding to an "attachment portion") to which the sensor board 100 is attached is formed on the first plate surface 121a of the bracket member 120. The protrusion 130 extends from the first plate surface 121a toward the flange portion 62 in the axial direction. A plurality of protrusions 130 (three are illustrated in the figure) are formed spaced apart in the circumferential direction. Of the plurality of protrusions 130, the protrusions 130 at both ends in the circumferential direction are protrusions for attaching both ends of the sensor board 100 in the circumferential direction. Of the plurality of protrusions 130, the protrusion 130 sandwiched between the protrusions 130 at both ends in the circumferential direction is a protrusion for attaching an intermediate portion of the sensor board 100 in the circumferential direction.

[0049] Each protrusion 130 has a bolt insertion hole 132 formed therein that penetrates in the axial direction and through which a board mounting bolt 131 is inserted. Meanwhile, the sensor board 100 has the same number of female screw holes 101 as the bolt insertion holes 132 formed therein, into which the male screws of the board mounting bolts 131 are screwed.

[0050] The bracket member 120 and the sensor board 100 have a configuration that makes it easy to position the sensor board 100 relative to the bracket member 120. More specifically, the sensor board 100 has a first plate surface 102a and a second plate surface 102b that is the back surface of the first plate surface 102a. Positioning pins 103 that extend axially toward the bracket member 120 are provided at both circumferential ends of the second plate surface 102b. Of the multiple protrusions 130, the protrusions 130 at both circumferential ends are formed with pin holes 133 that extend axially and through which the positioning pins 103 are inserted.

[0051] By inserting the positioning pins 103 into the pin holes 133, the female screw holes 101 at both circumferential ends of the sensor board 100 and the bolt insertion holes 132 of the protrusions 130 are aligned. In this aligned state, the board mounting bolts 131 are inserted into the bolt insertion holes 132 from the second plate surface 121b side of the bracket member 120, and the male threads of the board mounting bolts 131 are screwed into the female screw holes 101. As a result, the sensor board 100 is fixed to the bracket member 120 while maintaining a predetermined relative positional relationship between the sensor board 100 and the bracket member 120. In this case, the plate surfaces of the sensor board 100 and the bracket member 120 are parallel to each other. The sensor board 100 is supported by the protrusions 130 while being spaced apart from the first plate surface 121a of the bracket member 120. The sensor board 100 is disposed so as not to be displaceable relative to the knuckle 15 serving as a base.

[0052] When an excitation voltage is applied to the excitation coil 110 of the sensor board 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 board 100 is disposed radially inward of the air intake 31 of the disc rotor 21. Furthermore, since the sensor board 100 and the first plate surface 121a of the bracket member 120 are separated by the protrusion 130, an air passage is formed between the sensor board 100 and the first plate surface 121a. In this case, as the disc rotor 21 rotates, airflow is generated from this air passage toward the air intake 31. As a result, not only the first plate surface 121a of the sensor board 100 but also the second plate surface 121b can be cooled.

[0053] The bracket member 120 is formed with bolt insertion holes 123 that penetrate from the first plate surface 121a to the second plate surface 121b and through which the bolts 16 are inserted. In this embodiment, three bolt insertion holes 123 are formed spaced apart in the circumferential direction.

[0054] An extension 124 extending toward the dust cover 70 in the axial direction is formed on the periphery of the through hole 122 of the bracket member 120. The extension 124 is formed over the entire periphery of the periphery of the through hole 122.

[0055] 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.

[0056] 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 extension portion 124 of the bracket member 120 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.

[0057] 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.

[0058] The hub bearing 40 has hub mounting portions 52, the number of which is the same as the number of bolt insertion holes 123. The hub mounting portions 52 are spaced apart in the circumferential direction. Each hub mounting portion 52 has a female screw hole 52a that penetrates in the axial direction and into which the bolt 16 is screwed. Each hub mounting portion 52 has a flat surface 52b that extends in a direction perpendicular to the axial direction.

[0059] In a front view of the plate surface of the bracket member 120, the sensor board 100 and the bolt insertion holes 123 are arranged at positions where they do not overlap. Furthermore, in a front view of the plate surface of the bracket member 120, the hub mounting portion 52 and the bolt insertion holes 123 are arranged at positions where they do not overlap in the circumferential direction. This makes it possible to prevent the sensor board 100 from interfering with the hub mounting portion 52 when the first plate surface 121a of the bracket member 120, to which the sensor board 100 is attached, is brought into contact (specifically, surface contact) with the flat surface 52b of the hub mounting portion 52.

[0060] The hub bearing 40 and the bracket member 120 are configured to align the central axis LCi of the inner ring member 60 of the hub bearing 40 with the center of the through hole 122 of the bracket member 120. Specifically, as shown in FIG. 12 , a groove 53 extending in the axial direction is formed on the side surface of the outer ring member 50. Meanwhile, a positioning protrusion 125 extending in the axial direction is formed on the first plate surface 121a of the bracket member 120. The positioning protrusion 125 is fitted into the groove 53, the first plate surface 121a of the bracket member 120 abuts against the flat surface 52b, and the outer cylindrical portion 51 is fitted into the through hole 122. This aligns the central axis LCi of the inner ring member 60 with the center of the through hole 122, contributing to improved load calculation accuracy. Note that the target member 80 is not shown in FIG. 12 .

[0061] The bracket member 120, the dust cover 70, and the knuckle 15 are provided with a structure that facilitates relative positioning of the dust cover 70 and the knuckle 15 with respect to the bracket member 120. More specifically, the knuckle 15 is provided with a positioning pin 15c that extends axially toward the bracket member 120. The first wall portion 73 of the dust cover 70 is formed with a pin hole 76 that extends axially and through which the positioning pin 15c is inserted. The bracket member 120 is formed with a pin hole 126 that extends axially and through which the positioning pin 15c is inserted.

[0062] The end of the through hole 15a of the knuckle 15 on the bracket member 120 side in the axial direction is an expanded diameter portion 15d whose radial dimension is enlarged. The positioning pin 15c is inserted into the pin holes 76, 126, and the extension portion 124 of the bracket member 120 is fitted into the expanded diameter portion 15d. This aligns the centers of the through holes 15a, 72, 122. The extension portion 124 and the expanded diameter portion 15d can improve the alignment accuracy.

[0063] The bracket member 120, the first wall portion 73 of the dust cover 70, and the knuckle 15 are formed with cable insertion holes 127, 77, and 15e through which the cable 116 connected to the connector 115 of the sensor board 100 is inserted.

[0064] To improve the detection accuracy of the displacements ΔZ and ΔY, the relative position of the sensor substrate 100 with respect to the central axis of rotation of the hub bearing 40 is important. In the wheel unit 10, the outer ring member 50 of the hub bearing 40 is designed to fit into the through hole 15a of the knuckle 15. This design reduces the misalignment between the center of the through hole 15a and the central axis of rotation of the hub bearing 40.

[0065] In this embodiment, the above structure is used to improve the detection accuracy of the displacements ΔZ and ΔY. More specifically, the outer cylindrical portion 51 of the outer ring member 50 is fitted into the through hole 15a of the knuckle 15. Furthermore, the bracket member 120 is fixed to the knuckle 15 with the through hole 122 of the bracket member 120 fitted into the outer cylindrical portion 51. This makes it possible to reduce the deviation, with the knuckle 15 as the reference, between the through hole 122 of the bracket member 120 to which the sensor board 100 is fixed and the rotational center axis of the hub bearing 40. As a result, the relative position of the sensor board 100 and the target member 80 provided on the flange portion 62 of the hub bearing 40 can be set to an appropriate position for improving the detection accuracy of the displacements ΔZ and ΔY.

[0066] In this embodiment, the structure is such that foreign matter such as sand is less likely to enter the arrangement space of the target member 80 and the sensor substrate 100. More specifically, as shown in Figures 3, 4, 6 and 7, the target member 80 has a peripheral wall portion 86. The peripheral wall portion 86 is provided over the entire outer periphery of the base annular portion 81. The peripheral wall portion 86, the base annular portion 81 and the protrusion portion 82 are configured as a single member.

[0067] 3, the peripheral wall portion 86 extends radially inward in the vehicle width direction beyond a position facing the flat surface of the protrusion 82. In other words, the peripheral wall portion 86 extends to a position covering the protrusion 82 from the radial outside. This makes it difficult for foreign matter to enter the arrangement space of the detection target portion 84, and the detection target portion 84 can be protected from foreign matter.

[0068] In particular, in this embodiment, the peripheral wall portion 86 extends radially beyond a position facing the sensor substrate 100. In other words, the peripheral wall portion 86 extends to a position covering the sensor substrate 100 from the radial outside. This effectively prevents foreign matter from entering the arrangement space of the detection target portion 84 and the sensor substrate 100, and protects the detection target portion 84 and the sensor substrate 100 from foreign matter. As a result, for example, it is possible to prevent foreign matter from getting caught between the protrusion 82 of the detection target portion 84 and the sensor substrate 100.

[0069] 6 and 7, each of the protrusions 82 and the peripheral wall portion 86 are spaced apart in the radial direction. The reason for this will be explained. When an excitation voltage is supplied to the excitation coil 110, a magnetic flux is generated in the excitation coil 110. At least a portion of the generated magnetic flux interlinks with the receiving coils 111 and 112, thereby inducing a voltage in the receiving coils 111 and 112. The receiving coils 111 and 112 output a voltage signal corresponding to the relative displacement of the detection object portion 84 with respect to the sensor substrate 100. A displacement or a force is detected based on the output voltage signal.

[0070] Here, if the distance between the peripheral wall portion 86 and the convex portion 82 in the radial direction is small, there is a concern that part of the magnetic flux generated by the excitation coil 110 may flow to the peripheral wall portion 86. In this case, the relationship between the relative displacement and the output signals of the receiving coils 111 and 112 may deviate from the reference relationship (for example, the relationship assumed at the time of design). As a result, there is a concern that the detection accuracy of the displacement or force based on the output signals of the receiving coils 111 and 112 may decrease.

[0071] Therefore, each convex portion 82 and the peripheral wall portion 86 are separated from each other in the radial direction. As a result, it becomes difficult for part of the magnetic flux generated by the excitation coil 110 to flow to the peripheral wall portion 86. As a result, it is possible to suppress the occurrence of a situation where the relationship between the relative displacement of the detection target portion 84 with respect to the sensor substrate 100 and the output signals of the receiving coils 111 and 112 deviates from the reference relationship. Thus, according to the present embodiment, it is possible to suppress a decrease in the detection accuracy of the displacement or force while making it difficult for foreign matter to enter the arrangement space of the detection target portion 84.

[0072] Note that, as shown in FIG. 7, the radial separation distance between the convex portion 82 and the peripheral wall portion 86 is defined as LA, and the radial dimension of the convex portion 82 is defined as LB. In this case, the separation distance LA may be set, for example, to "LB / 3 ≤ LA < LB", "LB / 2 ≤ LA < LB", or "LB / 3 ≤ LA < 2LB / 3".

[0073] [[ID=II]] <Second Embodiment> Hereinafter, the second embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment. In the present embodiment, as shown in FIG. 13, a gap is provided between the peripheral wall portion 87 of the target member 80 and the disk peripheral wall portion

[0074] As a result, this gap can function as a heat insulating layer, and it is possible to make it difficult for the heat generated in the disk sliding portion 23 to be transmitted to the target member 80 and the sensor substrate 100. As a result, it is possible to suppress the temperature rise of the target member 80 and the sensor substrate 100.

[0075] Furthermore, the gap can be used as a passage for the airflow generated by the rotation of the disk rotor 21. This makes it difficult for the heat generated at the disk sliding portion 23 to be transmitted to the target member 80 and the sensor substrate 100, thereby suppressing the temperature rise of the target member 80 and the sensor substrate 100.

[0076] By suppressing the temperature rise of the target member 80, it is possible to suppress thermal deformation of the target member 80 and to suppress a decrease in the detection accuracy of displacement or force. Furthermore, by suppressing the temperature rise of the sensor substrate 100, it is possible to suppress the occurrence of a situation in which the reliability of the sensor substrate 100 is reduced.

[0077] <Modification of the second embodiment> 14, the boundary between the base annular portion 81 and the peripheral wall portion 87 may be a curved portion 88 that connects the base annular portion 81 and the peripheral wall portion 87 with a smooth curved surface. In this case, the strength of the target member 80 can be improved and water is less likely to accumulate at the boundary portion.

[0078] Third Embodiment The third embodiment will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in Figures 15 and 16, the peripheral wall portion 89 of the target member 80 widens radially outward as it moves inward in the vehicle width direction in the axial direction. This makes it easy to drain the infiltrating water from the lower end side of the peripheral wall portion 89, even if water infiltrates the arrangement space of the detection object portion 84 and the sensor board 100. In this way, this embodiment can protect the detection object portion 84 and the sensor board 100 from foreign matter while improving drainage within the target member 80.

[0079] <Fourth embodiment> The fourth embodiment will be described below with reference to the drawings, focusing on the differences from the second embodiment. In this embodiment, as shown in Fig. 17, radially protruding heat dissipation fins 90 are arranged in a circumferential direction on the outer periphery of the peripheral wall portion 86. This allows the target member 80 to be cooled effectively, and makes it possible to suppress a rise in temperature of the target member 80.

[0080] Each heat dissipation fin 90 extends at an angle relative to the axial direction while being spaced apart from the disk peripheral wall 25 and disk sliding portion 23 of the disk rotor 21. This increases the area of ​​the heat dissipation fin 90, improving cooling performance. Furthermore, airflow can be effectively generated in the gaps (see FIG. 14) between the peripheral wall 87 of the target member 80 and the disk peripheral wall 25 and disk sliding portion 23. As a result, temperature increases in the target member 80 and the sensor substrate 100 can be effectively suppressed.

[0081] Fifth Embodiment The fifth embodiment will be described below with reference to the drawings, focusing on the differences from the second embodiment. In this embodiment, as shown in Figures 18 and 19, the outer shape of a bracket member 220 is circular. An annular seal member 229 is provided between the outer peripheral edge of the bracket member 220 and the peripheral wall portion 87. This effectively prevents foreign matter such as water or dust from entering the radially inner space of the peripheral wall portion 87.

[0082] Except for the fact that the bracket member 220 has a circular outer shape, it basically has the same shape as the bracket member 120 described in the previous embodiment. The reference numerals of the components of the bracket member 220 are obtained by changing the hundredths of the reference numerals of the components of the bracket member 120 to 2. For example, in the bracket member 220 shown in FIG. 19 , 221b, 222, 223, 226, 227, and 230 correspond to the second plate surface 121b, through-hole 122, bolt insertion hole 123, pin hole 126, cable insertion hole 127, and protrusion 130 of the bracket member 120.

[0083] A groove 228 is formed on the outer peripheral edge of the bracket member 220, recessed in the radial direction of the bracket member 220. The groove 228 is formed over the entire outer peripheral edge of the bracket member 220.

[0084] A seal member 229 is provided in the groove 228. In this embodiment, the seal member 229 is a packing (for example, a mechanical seal) or an O-ring.

[0085] The annular portion of the peripheral wall portion 87 that faces the seal member 229 in the radial direction serves as a sliding portion 87a against which the seal member 229 is pressed.

[0086] According to the present embodiment described above, it is possible to suitably prevent foreign matter such as water or dust from entering the radially inner space of the peripheral wall portion 87. Furthermore, in this embodiment, the bracket member 220 can be used as a cover member that prevents foreign matter from entering.

[0087] <Modification of the Fifth Embodiment> The cover member on which the seal member 229 is provided may be a separate member from the bracket member 220 .

[0088] Sixth Embodiment The sixth embodiment will be described below with reference to the drawings, focusing on the differences from the fifth embodiment. In this embodiment, a lip seal is used as the seal member 240, as shown in FIG.

[0089] As shown in Fig. 21, the seal member 240 is provided over the entire outer circumferential edge of the bracket member 220. Fig. 22 is a cross-sectional view taken along line 22-22 of Fig. 21. Figs. 21 and 22 show the bracket member 220 in a state before being attached to the inner circumferential side of the peripheral wall portion 87 as shown in Fig. 20. The seal member 240 includes an annular portion 241 that is annular and provided over the entire outer circumferential edge of the bracket member 220, and a protruding portion 242 that protrudes radially outward from the annular portion 241. The protruding portion 242 has a tapered shape.

[0090] 21 and 22, the peripheral wall portion 87 is fitted from the flange portion 62 side in the axial direction. As a result, the protruding portion 242 of the seal member 240 bends toward the knuckle 15 in the axial direction, and the seal member 240 assumes the shape shown in FIG.

[0091] According to the present embodiment described above, foreign matter such as water and dust can be prevented from entering the radially inner space of the peripheral wall portion 87 in an appropriate manner.

[0092] Seventh Embodiment The seventh embodiment will be described below with reference to the drawings, focusing on differences from the second embodiment. In this embodiment, as shown in Fig. 23, the dust cover 70 includes a sub-wall portion 78. The sub-wall portion 78 is arranged so as not to be displaceable relative to the knuckle 15. The sub-wall portion 78 extends in the axial direction from the first wall portion 73 toward the flange portion 62 to a position facing the peripheral wall portion 87 in the radial direction. The sub-wall portion 78 is cylindrical.

[0093] In the present embodiment, the sub-wall portion 78 extends to a position beyond the center position of the peripheral wall portion 87 in the axial direction, and more specifically, extends to a position facing the base annular portion 81 in the radial direction. The sub-wall portion 78 is provided between the peripheral wall portion 87 and the disc peripheral wall portion 25. In other words, the sub-wall portion 78 covers the peripheral wall portion 87 from the radially outer side.

[0094] The sub-wall 78 can function as a heat insulating layer. This makes it difficult for heat generated in the disk sliding portion 23 to be transmitted to the target member 80 and the sensor substrate 100, thereby suppressing temperature increases in the target member 80 and the sensor substrate 100.

[0095] <Other embodiments> The above-described embodiments may be modified as follows.

[0096] In the seventh embodiment, the sub-wall portion is not limited to the dust cover 70, but may extend from the bracket member 120, for example.

[0097] In the target member 80, a hole that passes through the base annular portion 81 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.

[0098] The sensor board 100 may be attached to the outer ring member 50 instead of the bracket members 120 and 220 .

[0099] In the target member, there may be no gap between each of the protrusions and the peripheral wall.

[0100] The peripheral wall does not necessarily have to be configured as a single member together with the target member, but may be a separate member (peripheral wall member) from the target member. In this case, maintenance becomes easier, for example, replacement of the peripheral wall member becomes easier.

[0101] 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 axially 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.

[0102] The circumferential center positions of the first and second receiving coils 111, 112 may be located at a position axially facing the right or left end of the target member 80, rather than at a position axially facing the lower or upper end of the target member 80. In this case, the sensor board 100 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.

[0103] The disc rotor is not limited to a ventilated disc, but may be, for example, a solid disc made of a single circular plate. [Explanation of symbols]

[0104] 10...wheel unit, 15...knuckle, 17...hub bolt, 40...hub bearing, 80...target member, 81...base annular portion, 86...circumferential wall portion, 100...sensor board, 110...excitation coil, 111, 112...receiving coils

Claims

1. Wheels (11, 14) of a vehicle; a hub bearing (40) that rotatably supports the wheel relative to a knuckle (15) of the vehicle; A detection device applied to a wheel unit (10) comprising: The hub bearing is a first bearing member (50) having a first cylindrical portion (51) extending in an axial direction, which is the direction of the rotational center axis of the hub bearing, and fixed to the knuckle; 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 knuckle, a sensor substrate (100) provided at a position shifted toward the knuckle with respect to the flange portion in the axial direction; a target member (80) having a base annular portion (81) extending in a circumferential direction of the second cylindrical portion around the rotation central axis and forming an annular shape, and a peripheral wall portion (86, 87, 89); Equipped with A detection target portion (84) is formed in a portion of the base annular portion that faces the sensor board in the axial direction, and the detection target portion (84) is formed by alternately providing, in the circumferential direction, convex portions (82) that protrude toward the knuckle in the axial direction and portions (83) that recede toward the flange portion in the axial direction relative to the convex portions, The peripheral wall portion extends in the axial direction from the outer peripheral edge portion of the base annular portion toward the knuckle side at least to a position where it covers the protrusion from the outside in the radial direction.

2. the target member is made of a magnetic material; The sensor substrate includes: an excitation coil (110) to which an excitation voltage is supplied; receiving coils (111, 112) in which a voltage is induced when an excitation voltage is supplied to the excitation coil; and the receiving coil outputs a voltage signal corresponding to a relative displacement of the detection target portion with respect to the receiving coil; The detection device according to claim 1 , wherein each of the protrusions and the peripheral wall portion are spaced apart in the radial direction.

3. The detection device according to claim 2 , wherein the peripheral wall portion extends in the axial direction to a position where it covers the sensor board from the outside in the radial direction.

4. The detection device according to claim 3, wherein the peripheral wall portion (89) widens radially outward as it approaches the knuckle in the axial direction.

5. a disk-shaped cover member (220); a seal member (229, 240) provided on the outer peripheral edge of the cover member and having an annular shape; Equipped with a through hole (222) through which one of the first cylindrical portion and the second cylindrical portion that is disposed on the outer side in the radial direction is inserted is formed in a central portion of the cover member; The peripheral wall portion (87) extends in the axial direction to a position where it covers the outer peripheral edge portion of the cover member from the outside in the radial direction, 4. The detection device according to claim 3, wherein an annular portion of the peripheral wall portion that faces the seal member in the radial direction is a sliding portion (87a) against which the seal member is pressed.

6. the cover member is a bracket member to which the sensor board is attached and which is fixed to the first bearing member, the bracket member is disposed between the knuckle and the detection target portion in the axial direction, The detection device according to claim 5 , wherein the sensor board is attached to a portion of the bracket member that faces the detection target in the axial direction.

7. 7. The detection device according to claim 1, wherein the peripheral wall portion is a separate member from the target member.

8. 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 substrate; an annular disk sliding portion (23) extending radially outward from an end portion of the disk peripheral wall portion in the axial direction; and An air passage (30a) is formed in the disc sliding portion, extending from an air intake port (31) formed on the inside in the radial direction to an air discharge port (32) formed on the outside in the radial direction, the sensor substrate and the detection target are disposed inside the disk rotor in the radial direction, 7. The detection device according to claim 1, wherein a gap is provided between the peripheral wall of the disk and the peripheral wall of the target member.

9. A sub-wall portion (78) is provided which is arranged so as not to be displaceable relative to the knuckle, The detection device according to claim 8 , wherein the sub-wall portion extends from the knuckle side toward the flange portion side in the axial direction to a position facing the peripheral wall portion in the radial direction.

10. The detection device according to any one of claims 1 to 6, wherein heat dissipation fins (90) that protrude in the radial direction are provided on an outer periphery of the peripheral wall portion and are aligned in the circumferential direction.

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