Detection device

Abstract

To provide a detection device capable of suppressing temperature rise of a sensor substrate and a detection object part.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 is provided with convex portions and concave portions alternately in the circumferential direction. The convex portion and the concave portion constitute a detection target portion. The detecting device includes an impeller member 130. The impeller member 130 is arranged between the detection object part and the disk sliding part, and generates an air flow in the radial direction by integrally rotating with the target member 80.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 detection target portion as components for detecting a force acting on a wheel. The sensor board is provided at a position offset toward the knuckle with respect to the flange portion in the axial direction. The detection target portion is provided at a portion of the flange portion that faces the sensor board in the axial direction and has an annular shape extending in the circumferential direction of the second cylindrical portion. The detection target portion is provided with convex portions that protrude toward the knuckle in the axial direction and portions that recede from the convex portions on the opposite side of the knuckle in the axial direction, alternately provided in the circumferential direction.

[0006] To apply a braking force to a rotating wheel, a brake pad is pressed against a disc sliding portion of a disc rotor fixed to a flange portion. In this case, heat is generated due to friction between the disc sliding portion and the brake pad. The generated heat increases the temperature of the radially inner space of the disc sliding portion, which in turn increases the temperature of the sensor substrate and the detection target portion disposed in that space. The increase in temperature of the sensor substrate and the detection target portion can affect, for example, the output signal of the sensor substrate, which can result in a decrease in the accuracy of force detection.

[0007] A primary object of the present disclosure is to provide a detection device that can suppress temperature increases in a sensor substrate and a detection target portion. [Means for solving the problem]

[0008] The present disclosure provides a vehicle wheel; a hub bearing that rotatably supports the wheel relative to a knuckle of the vehicle; a disc rotor constituting a brake device; 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 and to which the disk rotor is fixed; 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, the disk rotor has an annular disk sliding portion disposed radially outward of the flange portion, a sensor board provided at a position shifted toward the knuckle with respect 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 board 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 knuckle in the axial direction and portions that recede from the convex portions in the axial direction to the opposite side of the knuckle, alternately in the circumferential direction.

[0009] The present disclosure includes a fan unit disposed between the sensor substrate and the detection target and the disk sliding portion in the radial direction, and rotating integrally with the detection target to generate an air flow in the radial direction.

[0010] This can promote the dissipation of heat from the sensor substrate and the periphery of the detection target, thereby suppressing temperature increases in the sensor substrate and the detection target. [Brief explanation of the drawings]

[0011] [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. 10 is a view of the target member as seen from the knuckle side. [Figure 6] FIG. [Figure 7] FIG. 2 is a diagram showing the electrical configuration of a sensor substrate and a processing unit. [Figure 8] FIG. 10 is a perspective view of a disk rotor according to a second embodiment. [Figure 9] Partially enlarged view of the wheel unit. [Figure 10] FIG. 10 is a perspective view of an impeller member according to a third embodiment. [Figure 11] FIG. 10 is a perspective view of an impeller member according to a fourth embodiment. [Figure 12] FIG. 10 is a perspective view of a fan-equipped target member according to a fifth embodiment. [Figure 13] FIG. 10 is a view of the target member as seen from the knuckle side. [Figure 14] FIG. 10 is a perspective view of an assembly including a target member and a hub bearing. [Figure 15] FIG. 10 is a perspective view of a fan-equipped target member according to a sixth embodiment. [Figure 16] FIG. 10 is a view of the target member as seen from the knuckle side. [Figure 17] FIG. 10 is a perspective view of an assembly including a target member and a hub bearing. DETAILED DESCRIPTION OF THE INVENTION

[0012] 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.

[0013] 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.

[0014] The wheel unit 10 as a mechanical device will be described with reference to Figures 1 to 4. 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.

[0015] 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.

[0016] 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 (not shown). The brake caliper 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. The brake caliper is fixed with bolts to a knuckle 15, which serves as a base.

[0017] 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.

[0018] 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, into which the inner ring member 60 of the hub bearing 40 is fitted. In the bottom surface portion 24, bolt insertion holes 27, through which hub bolts 17 are inserted, are formed circumferentially around the mounting hole 26, axially penetrating the bottom surface portion 24. The mounting holes 26 and the bolt insertion holes 27 are arranged side by side 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.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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 axis of rotation 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. The target member 80 is fixed to, for example, the flange portion 62, and rotates integrally with the inner ring member 60.

[0028] As shown in Fig. 5, 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 in a row in the circumferential direction on the portion of the target member 80 facing the sensor board 100. 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.

[0029] 5, 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.

[0030] Next, the sensor substrate 100 will be described.

[0031] 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.

[0032] The sensor substrate 100 has an arc shape that fits the detection target portion 84. As shown in FIG. 7, 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 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] Next, the load calculation process will be described.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] The sensor substrate 100 and the load calculation process are described in, for example, Japanese Patent Application Laid-Open No. 2023-130285.

[0041] 3 and 4, a configuration for fixing the sensor board 100 to the outer ring member 50 of the hub bearing 40 will be described. The wheel unit 10 includes a bracket member 120. The bracket member 120 is plate-shaped and has an annular shape. The bracket member 120 is made of a non-magnetic material, such as 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, penetrating in the axial direction and into which the outer cylindrical portion 51 is fitted.

[0042] Of the two plate surfaces of the bracket member 120, the sensor board 100 is fixed to the plate surface on the flange portion 62 side. 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 bracket member 120 and the outer ring member 50 are fixed to the knuckle 15, which serves as a base, by bolts, for example. As a result, the bracket member 120 and the outer ring member 50 are positioned so that they cannot be displaced relative to the knuckle 15.

[0043] The bracket member 120 is formed with bolt insertion holes 123 that penetrate in the axial direction and through which the bolts 16 are inserted. In this embodiment, three bolt insertion holes 123 are formed spaced apart in the circumferential direction.

[0044] 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. As shown in Fig. 3, each hub mounting portion 52 has a female threaded 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.

[0045] 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 prevents the sensor board 100 from interfering with the hub mounting portion 52 when the plate surface of the bracket member 120, with the sensor board 100 attached, is brought into contact (specifically, surface contact) with the flat surface 52b of the hub mounting portion 52. The bracket member 120 is also formed with a cable insertion hole 127 through which the cable 116 connected to the connector 115 of the sensor board 100 is inserted.

[0046] Incidentally, the sensor board 100 may be directly attached to the outer ring member 50 without providing the bracket member 120.

[0047] As shown in FIGS. 3 and 6, the wheel unit 10 is provided with an impeller member 130 (corresponding to a "fan section") in order to promote heat dissipation from the arrangement space of the target member 80 and the sensor board 100. The impeller member 130 is a centrifugal fan that draws in air from the axial direction and blows the drawn-in air radially outward, such as a sirocco fan or a turbo fan. The impeller member 130 may be made of the same material as the target member 80, or may be made of a different material from the target member 80, for example. The impeller member 130 of this embodiment will be described below.

[0048] The impeller member 130 includes a disk-shaped base mounting portion 131. The plate surface of the base mounting portion 131 abuts against the flat surface 52b of the flange portion 62. A base mounting hole 132 is formed in the center of the base mounting portion 131, into which the inner ring member 60 of the hub bearing 40 is fitted. In the base mounting portion 131, bolt insertion holes 133 are formed in a line in the circumferential direction around the base mounting hole 132, which pass through the base mounting portion 131 in the axial direction and into which the hub bolts 17 are inserted.

[0049] The impeller member 130 has a plurality of blade portions 134 arranged along the outer peripheral edge of the base mounting portion 131, and an annular ring portion 135 connecting the side of each blade portion 134 opposite to the side connected to the base mounting portion 131.

[0050] When the wheel 11 rotates in a specific direction, the vehicle moves forward. Each blade portion 134 extends radially inward at an angle relative to the specific direction. By extending radially inward, the radial dimension of the impeller member 130 can be reduced.

[0051] Next, a configuration for fixing the wheel 11, the disc rotor 21, and the impeller member 130 to the flange portion 62 will be described.

[0052] 2 and 3, the target member 80 and the impeller member 130 are provided radially inward of the disk peripheral wall portion 25 that constitutes the disk rotor 21. A bolt insertion hole 18a is formed in the disk mounting portion 18, penetrating in the axial direction. With the base mounting portion 131, the bottom surface portion 24, and the disk mounting portion 18 overlapping in this order on the mounting surface 62b of the flange portion 62, a hub bolt 17 is inserted into the bolt insertion holes 133, 27, and 18a. Because the base mounting portion 131 is sandwiched between the flat surface 52b and the bottom surface portion 24, the base mounting portion 131 is accurately fixed to the flange portion 62.

[0053] The disk mounting portion 18, disk rotor 21, and impeller member 130 are fixed to the hub bearing 40 by threading a nut 35 onto the hub bolt 17. This makes the target member 80, disk rotor 21, inner ring member 60, and impeller member 130 coaxial. The disk rotor 21, wheel 11, inner ring member 60, target member 80, and impeller member 130 rotate together.

[0054] 3, the blade portion 134 is disposed radially outward from the detection target portion 84 of the target member 80. When the impeller member 130 rotates in the specific direction about the central axis LCi, it generates an airflow from the inside to the outside in the radial direction. This allows heat to be released from the arrangement space of the target member 80 and the sensor substrate 100 to the radial outside of the impeller member 130, thereby facilitating heat dissipation in the arrangement space. As a result, temperature increases in the sensor substrate 100 and the target member 80 can be suppressed.

[0055] In particular, in this embodiment, since the disc rotor 21 is a ventilated disc, the heat dissipated radially outward from the impeller member 130 can be accurately dissipated to the outside via the air passage 30a, thereby enhancing the effect of suppressing temperature rises in the sensor substrate 100 and the target member 80.

[0056] Second Embodiment The second embodiment will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in Figures 8 and 9, the disc rotor 21 has through-holes 33 through which air flows at the boundary between the bottom surface portion 24 and the disc peripheral wall portion 25. A plurality of through-holes 33 are formed and aligned in the circumferential direction.

[0057] 9, the through holes 33 are formed radially outward of the base mounting portion 131. As the wheel 11 rotates, an airflow F is generated from the outside of the disc rotor 21 to the inside of the disc rotor 21 through the through holes 33. This can improve the cooling effect of the target member 80 and the sensor substrate 100, and can also improve the effect of suppressing temperature increases in the target member 80 and the sensor substrate 100.

[0058] <Modification of the second embodiment> The through holes for passing the air flow may be formed in only one of the bottom surface portion 24 and the disk peripheral wall portion 25, not necessarily in both of them.

[0059] Third Embodiment The third embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, as shown in Fig. 10, the structure of the impeller member 230 is modified.

[0060] Like the impeller member 130 of the first embodiment, the impeller member 230 includes a base mounting portion 231 having a base mounting hole 232 and a bolt insertion hole 233, blade portions 234, and a ring portion 235. However, the inclination direction of each blade portion 234 differs from that of the first embodiment. Specifically, each blade portion 234 extends radially outward at an angle relative to a specific direction.

[0061] When the impeller member 230 rotates in the specific direction about the central axis LCi, it generates an airflow from the inside to the outside in the radial direction, which makes it possible to suppress temperature increases in the sensor substrate 100 and the target member 80, similar to the first embodiment.

[0062] <Fourth embodiment> The fourth embodiment will be described below with reference to the drawings, focusing on the differences from the third embodiment. In this embodiment, as shown in Fig. 11, the structure of the impeller member 330 is modified.

[0063] Like the impeller member 230 of the third embodiment, the impeller member 330 includes a base mounting portion 331 having a base mounting hole 332 and a bolt insertion hole 333, blade portions 334, and a ring portion 335. However, the inclination direction of each blade portion 334 differs from that of the third embodiment. Specifically, each blade portion 334 extends radially inward in a direction perpendicular to the circumferential direction.

[0064] According to the present embodiment described above, the temperature rise of the sensor substrate 100 and the target member 80 can also be suppressed.

[0065] Fifth Embodiment The fifth embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, as shown in Figures 12 to 14, a fan portion is integrally formed with a target member.

[0066] The target member 180 includes a base mounting portion 181 that extends circumferentially of the inner cylindrical portion 61 around the central axis LCi and has an annular shape. Protrusions 182 are formed lined up in the circumferential direction on a portion of the base mounting portion 181 that faces the sensor board 100 in the axial direction. The flat surfaces between the protrusions 182 lined up in the circumferential direction form recesses 183. As a result, the protrusions 182 and recesses 183 are alternately provided in the circumferential direction. The protrusions 182 and recesses 183 form a detection target portion 184. The base mounting portion 181 is fixed to the inner ring member 60 of the hub bearing 40 in a state of contact with the flange portion 62.

[0067] Note that interference avoidance portions 185 that are recessed toward the convex portion 182 are formed on the portion of the base mounting portion 181 opposite the portion where the convex portion 182 is formed. The interference avoidance portions 185 are configured to avoid interference with the heads of the hub bolts 17. The same number of interference avoidance portions 185 as the hub bolts 17 are formed and lined up in the circumferential direction.

[0068] Similar to the impeller member 130 of the first embodiment, the target member 180 includes a blade portion 434 and a ring portion 435. The blade portion 434 and the ring portion 435 configure the fan portion 430.

[0069] According to the present embodiment described above, the temperature rise of the sensor substrate 100 and the target member 80 can also be suppressed.

[0070] 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, the structure of the fan unit 530 is modified as shown in Figures 15 to 17.

[0071] The target member 280 has a base mounting portion 281. A convex portion 282 and a concave portion 283 are formed in a portion of the base mounting portion 281 that faces the sensor board 100 in the axial direction. The convex portion 282 and the concave portion 283 form a detection target portion 284. The base mounting portion 281 is fixed to the inner ring member 60 in a state of contact with the flange portion 62. An interference avoidance portion 285 is formed in the base mounting portion 281.

[0072] The target member 280 includes a fan section 530 that includes blade sections 534 and a ring section 535. The blade sections 534 are inclined radially outward.

[0073] According to the present embodiment described above, it is possible to achieve the same effects as the fifth embodiment.

[0074] <Other embodiments> The above-described embodiments may be modified as follows.

[0075] The through-holes 33 of the second embodiment may be formed in the disc rotors 21 of the third to fifth embodiments.

[0076] Instead of the recess, the target member may have a hole that penetrates the target member in the axial direction. The hole is a portion that is recessed toward the flange portion 62 relative to the protrusion.

[0077] In the first to fourth embodiments, the target member 80 may not be provided, and a detection object having a convex portion and a concave portion may be formed on the flange portion 62.

[0078] 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.

[0079] The sensor substrate 100 may be provided so that the circumferential center positions of the first and second receiving coils 111, 112 are not axially opposed to the lower end or upper end of the target member 80, but are axially opposed to the right end or left end of the target member 80. In this case, the processing unit 117 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.

[0080] 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]

[0081] 10...wheel unit, 15...knuckle, 40...hub bearing, 80...target member, 100...sensor board, 110...excitation coil, 111, 112...receiving coils, 130...impeller member.

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 disc rotor (21) constituting a brake device (20); 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 and to which the disk rotor is fixed; 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, The disk rotor has a disk sliding portion (23) that is disposed radially outward of the flange portion and has an annular shape, a sensor substrate (100) provided at a position shifted toward the knuckle with respect 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 board 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 knuckle in the axial direction and portions (83) that recede toward the opposite side of the knuckle from the convex portions in the axial direction, alternately in the circumferential direction, A detection device comprising a fan section (130, 230, 330, 430, 530) disposed between the sensor substrate and the detection target section and the disk sliding section in the radial direction, and rotating integrally with the detection target section to generate an air flow in the radial direction.

2. The fan section includes: a base mounting portion (131, 231, 331) that is fixed to a mounting surface (62b) of the flange portion on the opposite side from the knuckle side in the axial direction and has a circular outer shape; a plurality of blade portions (134, 234, 334) provided along the outer peripheral edge portion of the base mounting portion; an impeller member (130, 230, 330) having The detection device according to claim 1 , wherein the impeller member is configured to generate an airflow directed from the inside to the outside in the radial direction when rotating about the central rotation axis.

3. 3. The detection device according to claim 2, wherein an air passage (30a) is formed in the disc sliding portion, the air passage (30a) extending from an air intake (31) formed on the radially inner side to an air exhaust port (32) formed on the radially outer side.

4. The disk rotor is A disk-shaped bottom surface portion (24); a cylindrical disk peripheral wall portion (25) extending in the axial direction from an outer peripheral edge portion of the bottom surface portion on the radially outer side of the flange portion and the sensor substrate; and the disk sliding portion extends radially outward from an end portion of the disk peripheral wall portion in the axial direction, The base mounting portion is sandwiched between the mounting surface of the flange portion opposite to the knuckle side in the axial direction and the bottom surface portion, 4. The detection device according to claim 2, wherein a through hole (33) through which airflow passes is formed in at least one of the bottom surface portion and the disk peripheral wall portion in a radially outer portion of the base mounting portion.

Images