torque sensor

Abstract

A torque sensor (10) includes a housing (20) having a receiving portion (26) that receives a magnetic yoke assembly (40), and the magnetic yoke assembly (40) is disposed inside the housing (20) and is detachably attached to the housing (20). The magnetic yoke assembly (40) includes a seal member arrangement portion (44) that can arrange an O-ring (70) as a seal member, and a protruding portion (45) that is received inside the receiving portion (26). The protruding portion (45) has a plurality of pressing ribs (47) on an outer circumferential surface (46) that abut against a receiving portion inner wall (27) that is an inner wall of the receiving portion (26). An inclined connection portion (48) that is inclined with respect to an insertion direction of the protruding portion (45) and connects the seal member arrangement portion (44) and the protruding portion (45) is provided between the seal member arrangement portion (44) and the protruding portion (45). The pressing ribs (47) abut against the receiving portion inner wall (27) at a length that is shorter than a length at which the protruding portion (45) and the inclined connection portion (48) are combined in the insertion direction in which the protruding portion (45) is inserted into the receiving portion (26).

Description

Technical Field

[0001] This disclosure relates to torque sensors. Background Technology

[0002] As an example of a torque sensor that detects the torque applied to a rotating body of a steering device, there exists a torque sensor that detects torque by detecting magnetic changes. For example, the magnetic detection module described in Patent Document 1 includes: a multipole magnet fixed to an input shaft; a set of magnetic yokes fixed to an output shaft; a flux guiding member that guides the magnetic flux of the magnetic circuit to the magnetic sensor; and a magnetic sensor that detects the magnetic flux guided by the flux guiding member and converts it into a voltage signal.

[0003] In addition, Patent Document 1 describes an embodiment in which a sensor portion for housing a magnetic sensor is provided protruding from the front end face of the cylindrical portion, and the magnetic detection module is installed in the housing by inserting the cylindrical portion into the mounting hole of the housing. It also describes that an O-ring used as a sealing element is sandwiched between the mounting hole of the housing and the cylindrical portion inserted into the mounting hole.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2020-8547 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In Patent Document 1, the magnetic detection module has a housing assembly and a cover. Without using an O-ring, the housing assembly is installed separately onto the housing; with an O-ring, the cover is installed onto the housing assembly, and the O-ring is installed on the cover before being installed onto the housing. That is, in Patent Document 1, in the non-waterproof configuration, the magnetic detection module has its housing assembly installed separately onto the housing; in the waterproof configuration, the housing assembly is installed onto the housing through the cover with the O-ring. However, with the structure of installing the housing assembly through the cover with the O-ring, the number of components increases while balancing waterproof and non-waterproof specifications, thus easily increasing manufacturing costs.

[0009] This disclosure was made in view of the above circumstances, and its purpose is to provide a torque sensor that can suppress the increase in manufacturing costs while taking into account both waterproof and non-waterproof specifications.

[0010] Methods for solving problems

[0011] The torque sensor disclosed herein includes: a housing; and a magnetic yoke assembly disposed inside the housing and detachably mounted thereon. The housing has a housing portion for receiving the magnetic yoke assembly. The magnetic yoke assembly includes a sealing member configuration portion for configuring a sealing member and a protrusion housed inside the housing portion. The protrusion has a plurality of compression ribs on its outer peripheral surface that abut against the inner wall of the housing portion, which serves as the inner wall of the housing portion. The protrusion has a height difference relative to the sealing member configuration portion by having a smaller profile shape when viewed in an insertion direction into the housing portion than the profile shape of the sealing member configuration portion. An inclined connecting portion is provided between the sealing member configuration portion and the protrusion. The inclined connecting portion is inclined relative to the insertion direction and connects the sealing member configuration portion and the protrusion. The end of the compression rib on the side where the sealing member configuration portion is located in the insertion direction is connected to the inclined connecting portion. The compression rib abuts against the inner wall of the housing portion with a length shorter than the combined length of the protrusion and the inclined connecting portion in the insertion direction.

[0012] According to this structure, a sealing component mounting section is provided in the yoke assembly, allowing for the placement of a sealing component. Therefore, when using a torque sensor in a waterproof configuration, by mounting a sealing component in the sealing component mounting section and retracting the protrusion into the housing's storage section, the sealing between the yoke assembly and the housing can be ensured. Furthermore, when using a torque sensor in a non-waterproof configuration, by not mounting a sealing component in the sealing component mounting section and retracting the protrusion into the storage section, a yoke assembly of the same shape as that used in a waterproof configuration can be used even in a non-waterproof configuration. As a result, it is possible to suppress increases in manufacturing costs while accommodating both waterproof and non-waterproof configurations.

[0013] Furthermore, according to this structure, the protrusion of the magnetic yoke assembly has multiple compression ribs on its outer peripheral surface that abut against the inner wall of the receiving portion, which serves as the housing. Therefore, the protrusion can be positioned relative to the receiving portion while being received. Additionally, since the abutment length of the compression ribs relative to the inner wall of the receiving portion is shorter than the combined length of the protrusion and the inclined connecting portion, deformation of the protrusion caused by the abutment between the compression ribs and the inner wall of the receiving portion can be suppressed, and the abutment between the compression ribs and the inner wall of the receiving portion can be ensured. As a result, the flattening method of the O-ring, which serves as a sealing member in the sealing member placement portion of the magnetic yoke assembly, can be uniformly standardized, thus ensuring the O-ring's sealing performance uniformly throughout its entire circumference. Consequently, the sealing performance of the O-ring can be improved.

[0014] As a preferred embodiment, the length of the compression rib in the insertion direction from the position of the sealing member configuration portion to the end on the opposite side of the side where the sealing member configuration portion is located is shorter than the combined length of the protrusion and the inclined connecting portion in the insertion direction.

[0015] According to this structure, the length of the compression rib from the position of the sealing member arrangement portion in the insertion direction of the protrusion relative to the housing portion of the housing, to the end on the opposite side of the side where the sealing member arrangement portion is located, is shorter than the combined length of the protrusion and the inclined connecting portion in the same direction. Therefore, the abutment length of the compression rib relative to the inner wall of the housing portion can be shorter than the combined length of the protrusion and the inclined connecting portion. As a result, deformation of the protrusion caused by the abutment of the compression rib against the inner wall of the housing portion can be suppressed, and the flattening method of the O-ring disposed in the sealing member arrangement portion of the magnetic yoke assembly can be uniformly achieved by the abutment of the compression rib against the inner wall of the housing portion. As a result, the sealing performance of the O-ring can be improved.

[0016] As a preferred embodiment, the shaft comprises: a magnet mounted on one of two shafts connected by a torsion bar; and a stator mounted on the other shaft, wherein the compression ribs are disposed on the outer peripheral surfaces of the protrusions on both sides of the shaft in the axial direction.

[0017] According to this structure, the compression ribs are arranged on the outer peripheral surfaces of the protrusion on both sides of the shaft in the axial direction, thus enabling the magnetic yoke assembly to be mounted in the housing with high precision in the same direction relative to the housing. As a result, deviations in the magnetic flux detected by the magnetic yoke assembly when detecting steering torque can be suppressed, allowing for proper detection of steering torque.

[0018] As a preferred embodiment, the device comprises: a magnet mounted on one of two shafts connected by a torsion bar; and a stator mounted on the other shaft, wherein the compression ribs are disposed on the outer peripheral surfaces of the protrusion on both sides in a direction orthogonal to both the axial direction of the shaft and the insertion direction.

[0019] According to this structure, the compression ribs are arranged on the outer peripheral surfaces of the protrusion on both sides in a direction orthogonal to both the axial direction and the insertion direction of the shaft. Therefore, the position of the magnetic yoke assembly relative to the housing in the same direction can be precisely mounted to the housing. As a result, deviations in the magnetic flux detected by the magnetic yoke assembly when detecting steering torque can be suppressed, allowing for proper detection of steering torque.

[0020] As a preferred embodiment, the inner wall of the storage portion has: a tapered portion that decreases the distance between the inner wall of the storage portion and the outer peripheral surface of the protrusion as it moves from the opening side of the storage portion toward the inner side in the insertion direction; and a flat portion located in the insertion direction further inward than the tapered portion, such that the distance between the inner wall of the storage portion and the outer peripheral surface of the protrusion is constant, wherein the compression rib abuts against the inner wall of the storage portion at the flat portion.

[0021] According to this structure, the compression rib abuts against the flat portion of the inner wall of the receiving portion at a position separate from the sealing component arrangement. Therefore, even if the protrusion deforms due to the compression rib abutting against the inner wall of the receiving portion, the deformation of the protrusion is unlikely to affect the sealing component arrangement. Thus, by having the compression rib abut against the inner wall of the receiving portion, deformation of the sealing component arrangement associated with protrusion deformation can be more reliably suppressed, and the flattening method of the O-ring in the sealing component arrangement of the magnetic yoke assembly can be made more uniform. As a result, the sealing performance of the O-ring can be improved.

[0022] As a preferred embodiment, the inner wall of the receiving portion has: an enlarged diameter portion located on the opening side of the receiving portion in the insertion direction and separated from the outer peripheral surface of the protrusion; and a reduced diameter portion located in the insertion direction at a position further inward than the enlarged diameter portion, the distance between the reduced diameter portion and the outer peripheral surface of the protrusion being smaller than the distance between the enlarged diameter portion and the outer peripheral surface of the protrusion, wherein the compression rib abuts against the inner wall of the receiving portion at the reduced diameter portion.

[0023] According to this structure, the compression rib abuts against the inner wall of the receiving section at a position separate from the sealing member mounting section by abutting against the reduced diameter portion of the inner wall of the receiving section. Therefore, even if the protrusion deforms due to the compression rib abutting against the inner wall of the receiving section, the deformation of the protrusion is unlikely to affect the sealing member mounting section, and the deformation of the sealing member mounting section accompanying the deformation of the protrusion can be suppressed more reliably. As a result, the flattening method of the O-ring in the sealing member mounting section of the magnetic yoke assembly can be made uniform. Consequently, the sealing performance of the O-ring can be improved.

[0024] As a preferred embodiment, the housing has a sealing member abutment portion on the inlet side of the receiving portion in the insertion direction, for the sealing member to abut against the inner circumferential surface. The sealing member is disposed on the sealing member placement portion and abuts against both the sealing member placement portion and the sealing member abutment portion at a position on the inlet side of the receiving portion in the insertion direction.

[0025] According to this structure, the O-ring is positioned in the sealing member configuration section of the magnetic yoke assembly. At a position closer to the inlet side of the housing than the insertion direction of the protrusion relative to the receiving section, the O-ring abuts against both the sealing member contact section of the housing and the sealing member configuration section of the magnetic yoke assembly. Thus, the O-ring can prevent liquids such as water from entering from the outside of the housing towards the inside of the receiving section. As a result, the sealing performance of the O-ring can be effectively utilized, improving the waterproofness of the torque sensor.

[0026] Invention Effects

[0027] The torque sensor disclosed herein has the effect of suppressing the increase in manufacturing costs while also meeting both waterproof and non-waterproof specifications. Attached Figure Description

[0028] Figure 1 This is a schematic diagram illustrating the steering device of the first embodiment.

[0029] Figure 2 This is a sectional view of the main part, including the section containing the short shaft and the first pinion in which the torque sensor is configured.

[0030] Figure 3 This is a cross-sectional view of the main part of the torque sensor in the steering device of the first embodiment.

[0031] Figure 4 This is a schematic diagram illustrating the magnets, stator, and yoke of a torque sensor.

[0032] Figure 5 yes Figure 3 The cross-sectional view of the casing shown.

[0033] Figure 6 It is along Figure 3 A top view of the magnetic yoke assembly viewed from the AA direction.

[0034] Figure 7 This is a schematic diagram showing the state in which the protrusion of the magnetic yoke assembly is housed in the housing.

[0035] Figure 8 yes Figure 7 BB cross-sectional view.

[0036] Figure 9 It is an exploded 3D view of the short shaft, the first pinion, and the torque sensor.

[0037] Figure 10 This is a schematic diagram of the magnetic yoke assembly and storage unit when using a torque sensor in a non-waterproof configuration.

[0038] Figure 11This is a cross-sectional view of the housing of the torque sensor according to the second embodiment.

[0039] Figure 12 This is a top view of the yoke assembly of the torque sensor in the second embodiment.

[0040] Figure 13 This is a schematic diagram showing the state in which the protrusion of the magnetic yoke assembly is housed in the housing portion of the housing in the second embodiment.

[0041] Figure 14 This is a variation of the torque sensor in the second embodiment, and is a schematic diagram showing that the inner wall of the housing has an expanded diameter portion and a reduced diameter portion. Detailed Implementation

[0042] The present disclosure will now be described in detail with reference to the accompanying drawings. Furthermore, the present disclosure is not limited to methods for carrying out the invention described below (hereinafter referred to as embodiments). Additionally, the constituent elements in the following embodiments include elements readily conceived by those skilled in the art, substantially the same elements, and elements of so-called equivalent scope. Moreover, the constituent elements disclosed in the following embodiments can be appropriately combined.

[0043] [First Implementation Method]

[0044] Figure 1 This is a schematic diagram illustrating the steering device 80 of the first embodiment. (As shown) Figure 1 As shown, the steering system 80 includes a steering wheel 81, a steering shaft 82, a universal joint 84, an intermediate shaft 85, a universal joint 86, a short shaft 87, a steering gear 88, and a tie rod 89, arranged in the order of transmitting the force applied by the operator. Additionally, the steering system 80 includes a control unit (hereinafter referred to as an ECU (Electronic Control Unit)) 100, a torque sensor 10, and an electric motor 102. The vehicle speed sensor 101 is installed in the vehicle and outputs a vehicle speed signal V to the ECU 100 via CAN (Controller Area Network) communication.

[0045] The steering shaft 82 is connected to the steering wheel 81 at one end and to the universal joint 84 at the other end.

[0046] The intermediate shaft 85 is connected to a universal joint 84 at one end and to a universal joint 86 at the other end. The short shaft 87 is connected to a universal joint 86 at one end and to a torque sensor 10 at the other end. The torque sensor 10 is connected to the short shaft 87 at one end and to a first pinion 88a of the steering gear 88 at the other end.

[0047] In detail, the first pinion 88a is a shaft-shaped component with a gear (not shown) meshing with the rack 88b described later formed at the end opposite to the side connected to the short shaft 87. The short shaft 87 and the first pinion 88a are connected via a torsion bar 87a (see reference). Figure 2 The torsion bar 87a is connected to the short shaft 87 at one end and to the first pinion 88a at the other end. The torsion bar 87a transmits rotational torque between the short shaft 87 and the first pinion 88a.

[0048] The torque sensor 10 is a torque detection device that detects the torque acting on the shaft connected to the torque sensor 10, and detects the rotational torque transmitted between the short shaft 87 and the first pinion 88a via the torsion bar 87a. That is, the short shaft 87 and the first pinion 88a connected via the torsion bar 87a become the shafts to be detected when the torque sensor 10 detects the torque.

[0049] The steering gear 88 includes a first pinion 88a, a rack 88b, and a second pinion 88c. The first pinion 88a is connected to a short shaft 87 via a torsion bar 87a. The rack teeth (not shown) formed on the rack 88b mesh with the first pinion 88a. Additionally, the rack 88b meshes with the second pinion 88c at a different position than the first pinion 88a.

[0050] An electric motor 102 is connected to a second pinion 88c via a worm gear reducer (not shown). The second pinion 88c is capable of rotating by a driving force transmitted from the electric motor 102. The electric motor 102 rotates the second pinion 88c via the worm gear reducer (not shown). The electric motor 102 is, for example, a brushless motor, but it can also be a motor equipped with brushes (slider elements) and a commutator (rectifier).

[0051] The steering gear 88 converts the rotational motion transmitted to the first pinion 88a and the second pinion 88c into linear motion via the rack 88b disposed inside the rack housing (not shown). The steering device 80 of the first embodiment is a double-pinion assisted type where the rack 88b performs linear motion via the rotational motion transmitted from the first pinion 88a and the second pinion 88c. The tie rod 89 is connected to the rack 88b. That is, the steering device 80 is a rack and pinion type electric power steering device.

[0052] The torque sensor 10 detects the steering force of the driver transmitted to the steering shaft 82 via the steering wheel 81 as the steering torque. The vehicle speed sensor 101 detects the vehicle speed (vehicle speed) of the vehicle equipped with the steering device 80. The electric motor 102, the torque sensor 10, and the vehicle speed sensor 101 are electrically connected to the ECU 100.

[0053] The ECU 100 controls the operation of the electric motor 102. Additionally, the ECU 100 obtains signals from the torque sensor 10 and the vehicle speed sensor 101. Specifically, the ECU 100 obtains the steering torque T from the torque sensor 10 and the vehicle speed signal V from the vehicle speed sensor 101. With the ignition switch 103 on, the ECU 100 supplies power from the power supply unit (e.g., the vehicle's battery) 104. The ECU 100 calculates the auxiliary steering command value based on the steering torque T and the vehicle speed signal V. Then, the ECU 100 adjusts the power value E supplied to the electric motor 102 based on this calculated auxiliary steering command value. The ECU 100 obtains information about the induced voltage from the electric motor 102 or information output from a rotation detection device such as a rotary transformer installed on the electric motor 102 as operation information M.

[0054] The steering force input to the operator (driver) of the steering wheel 81 is transmitted to the first pinion 88a. The steering force transmitted to the first pinion 88a is transmitted to the tie rod 89 via the steering gear 88, causing wheel displacement.

[0055] Additionally, the steering force input to the steering wheel 81 by the operator is transmitted to the torque sensor 10, which is positioned along the steering force transmission path from the steering wheel 81 to the first pinion 88a. At this time, the ECU 100 obtains the steering torque T from the torque sensor 10 and the vehicle speed signal V from the vehicle speed sensor 101. Furthermore, the ECU 100 controls the operation of the electric motor 102. The auxiliary steering torque generated by the electric motor 102 is transmitted to the second pinion 88c.

[0056] The auxiliary steering torque transmitted to the second pinion 88c is transmitted to the tie rod 89 via the steering gear 88 to displace the wheels. That is, in addition to the steering force of the operator transmitted to the rack 88b via the first pinion 88a, the steering device 80 also uses the auxiliary steering torque of the electric motor 102 transmitted to the rack 88b via the second pinion 88c to displace the wheels.

[0057] like Figure 1 As shown, the steering device 80 is a double-pinion type that applies auxiliary force to the second pinion 88c, but it is not limited to this. The steering device 80 can also be, for example, a column-assisted type that applies auxiliary force to the steering shaft 82, or a single-pinion-assisted type that applies auxiliary force to the first pinion 88a, which are electric power steering devices. Alternatively, it can be a rack-assisted type electric power steering device that applies auxiliary force to the rack 88b via a ball screw, or a type that applies auxiliary force to the rack 88b without using pinions, such as a ball screw type.

[0058] Figure 2This is a main sectional view of the portion containing the short shaft 87 and the first pinion 88a in which the torque sensor 10 is configured. The short shaft 87 and the first pinion 88a are disposed inside the housing 20, which also serves as the housing for the torque sensor 10. The housing 20 has a first housing 20a and a second housing 20b connected to each other. The first housing 20a is axially positioned near the short shaft 87 and primarily covers the short shaft 87, while the second housing 20b is axially positioned near the first pinion 88a and primarily covers the first pinion 88a. In other words, at least a portion of the short shaft 87 and the first pinion 88a are disposed inside the first housing 20a and the second housing 20b, respectively. The first housing 20a is mounted to the second housing 20b by mounting bolts 28, thereby securing the first housing 20a to the second housing 20b.

[0059] Additionally, a bearing (not shown) is disposed inside the first housing 20a, and the short shaft 87 is rotatably supported on the first housing 20a via the bearing disposed inside the first housing 20a. Furthermore, a bearing (not shown) is also disposed inside the second housing 20b, and the first pinion 88a is rotatably supported on the second housing 20b via the bearing disposed inside the second housing 20b.

[0060] The short shaft 87 is rotatably supported on the first housing 20a, and the first pinion 88a is rotatably supported on the second housing 20b. Therefore, the short shaft 87 and the first pinion 88a connected by the torsion bar 87a become a single unit and are rotatably supported on the first housing 20a and the second housing 20b.

[0061] The housing 20 is mounted on the vehicle body in a non-rotatable state. The housing 20 supports the short shaft 87 and the first pinion 88a for free rotation by bearings configured in the first housing 20a and the second housing 20b.

[0062] The torque sensor 10 is disposed within the first housing 20a, and is positioned near the ends of a short shaft 87 (serving as a first shaft) and a first pinion 88a (serving as a second shaft) connected to the short shaft 87 via a torsion bar 87a. Both the short shaft 87 and the first pinion 88a are shafts with hollow portions, with the end of one shaft entering the inner side of the other shaft from the end of the other. In this embodiment, the short shaft 87 enters the inner side of the first pinion 88a.

[0063] A torsion bar 87a extends from the inside of the short shaft 87 to the inside of the first pinion 88a, with one end connected to the short shaft 87 and the other end connected to the first pinion 88a. That is, the short shaft 87 and the first pinion 88a are not directly connected but are connected via the torsion bar 87a, which is a shaft-like component. Therefore, the short shaft 87 and the first pinion 88a can rotate relative to each other; when the torsion bar 87a is torn, the short shaft 87 and the first pinion 88a rotate relative to each other along with the torsion bar 87a.

[0064] The torque sensor 10 is positioned near the end of the short shaft 87 and the first pinion 88a connected by a torsion bar 87a. By detecting the angle of relative rotation between the short shaft 87 and the first pinion 88a, the torque acting between the short shaft 87 and the first pinion 88a can be detected.

[0065] Figure 3 This is a cross-sectional view of the main part of the torque sensor 10 included in the steering device 80 of the first embodiment. Furthermore, in the following description, unless specifically stated regarding direction, the axial direction Z of the short shaft 87 and the first pinion 88a of the torque sensor 10 will be described as the axial direction Z. Similarly, the circumferential direction centered on the axis of the short shaft 87 and the first pinion 88a will be described as the circumferential direction of the torque sensor 10, and the radial direction centered on the axis of the short shaft 87 and the first pinion 88a will be described as the radial direction. Additionally, the radial direction of the torque sensor 10 will be described along the radial direction at the position where the magnetic yoke assembly 40 is arranged in the circumferential direction. Figure 3 The direction (left-right direction on the paper) is described as the length direction Y of the torque sensor 10 or the length direction Y of the magnetic yoke assembly 40. Additionally, the direction orthogonal to both the length direction Y and the axial direction Z is... Figure 3 The paper depth direction (as described in the text) is used as the width direction X of the torque sensor 10 or the width direction X of the magnetic yoke assembly 40. In the first embodiment, the length direction Y is the direction orthogonal to the axial direction Z in the cross section passing through the axis of the short shaft 87, the first pinion 88a and the center of the magnetic yoke assembly 40 in the width direction X.

[0066] The housing 20 is formed in a generally cylindrical shape, and a short shaft 87 and a first pinion 88a are arranged on the inner side of the inner circumferential surface 21 of the cylindrical shape. The housing 20 of the torque sensor 10 is located at a position on a portion of the axial Z of the housing 20, which is formed in a generally cylindrical shape. More specifically, the housing 20 of the torque sensor 10 is located at a position on a portion of the axial Z of the first housing 20a, which is one of the first housing 20a and the second housing 20b of the housing 20.

[0067] The torque sensor 10 has a magnetic yoke assembly 40, which is disposed inside the housing 20 and is detachably mounted on the housing 20. Specifically, the first housing 20a of the first housing 20a and the second housing 20b of the housing 20 has a receiving portion 26 for receiving the magnetic yoke assembly 40, which is formed into a hole-like shape that opens radially outward from the inner peripheral surface 21 of the housing 20.

[0068] The magnetic yoke assembly 40 is inserted radially toward the inner peripheral surface 21 from the outer radial direction relative to the housing 26. That is, the magnetic yoke assembly 40 is inserted in the longitudinal direction Y from the outer radial direction relative to the housing 20 toward the inner side relative to the housing 26. In the following description, the direction in which the magnetic yoke assembly 40 is inserted relative to the housing 26 will also be referred to as the insertion direction.

[0069] The yoke assembly 40 has a sensor housing 41, inside which a yoke 55, a Hall IC 50, and a circuit board 52 are disposed. The Hall IC 50 can convert the change in magnetic flux detected by the yoke 55 based on the change in torque transmitted between the short shaft 87 and the first pinion 88a into an electrical signal and output it. In addition to the yoke 55, Hall IC 50, and circuit board 52 of the yoke assembly 40, the torque sensor 10 also has a magnet 65 mounted on one of the two shafts connected by the torsion bar 87a (see reference). Figure 4 ) and the stator 60 mounted on the other side of the shaft (see reference) Figure 4 ).

[0070] Figure 4 This is a schematic diagram illustrating the general outline of the magnet 65, stator 60, and yoke 55 of the torque sensor 10. One of the magnet 65 and stator 60 of the torque sensor 10 is mounted on a first shaft, and the other is mounted on a second shaft. In a first embodiment, the magnet 65 is mounted on the outer peripheral surface of the short shaft 87, which serves as the first shaft, and the stator 60 is mounted on the outer peripheral surface of the first pinion 88a, which serves as the second shaft. The magnet 65 is formed in a generally cylindrical shape, becoming a ring-shaped permanent magnet with multiple magnetic poles 66 alternately arranged circumferentially. That is, the magnet 65 is a multipole magnet formed by the alternating N pole 66n and S pole 66s, which are different magnetic poles 66, arranged circumferentially in the ring-shaped magnet 65. In this embodiment, the magnet 65 is an 8-pole multipole magnet.

[0071] The stator 60 has a flange portion 61 and teeth 62. The teeth 62 are for the flow of magnetic flux from the magnet 65, and the flange 61 is for the flow of magnetic flux from the magnet 65 from the teeth 62 to the stator 60 towards the magnetic yoke 55. The flange 61 is formed into an annular plate shape with its thickness direction aligned with the axial direction Z. The teeth 62 extend from the inner periphery of the annular flange 61 toward the axial direction Z of the flange 61, forming a plate shape with its thickness direction aligned with the radial direction of the flange 61. Furthermore, a plurality of teeth 62 are arranged at intervals in the circumferential direction of the flange 61. The teeth 62 are arranged in the same number as the magnetic poles 66 of the magnet 65.

[0072] The stator 60 thus formed has a first stator 60a and a second stator 60b, which are a pair of stators 60 formed with the same shape. The first stator 60a and the second stator 60b each have a flange portion 61 and a tooth portion 62. That is, the first stator 60a has an annular first flange portion 61a and a plurality of first teeth portions 62a, and the second stator 60b has an annular second flange portion 61b and a plurality of second teeth portions 62b. The first stator 60a and the second stator 60b are both mounted on the same shaft with their flange portions 61 located on the same axis and in a direction that separates them from the other stator 60. In the first embodiment, the first stator 60a and the second stator 60b are both mounted on the outer peripheral surface of the first pinion 88a.

[0073] That is, the first stator 60a is configured such that the first tooth 62a extends from the first flange 61a toward the second stator 60b, and the second stator 60b is configured such that the second tooth 62b extends from the second flange 61b toward the first stator 60a. At this time, multiple first teeth 62a and second teeth 62b are spaced apart from each other on the first flange 61a and the second flange 61b, thus the first stator 60a and the second stator 60b are combined in such a way that the teeth 62 of their own stator 60 are located in the circumferential direction at the portion of the other stator 60 where the teeth 62 are absent.

[0074] A magnet 65, mounted on the outer peripheral surface of the short shaft 87, is disposed radially inside the first stator 60a and the second stator 60b in this combination. Furthermore, the magnet 65 and the stator 60 are arranged with their axial direction Z aligned with the axial direction Z of the short shaft 87 and the first pinion 88a. Therefore, the magnet 65 and the stator 60 are mounted on the short shaft 87 and the first pinion 88a with the outer peripheral surface of the magnet 65 facing the teeth 62 of the stator 60. With the magnet 65 and the stator 60 arranged in the aforementioned positional relationship, when the short shaft 87 and the first pinion 88a rotate slightly relative to each other due to the torque transmitted between them via the torsion bar 87a, the relative positional relationship between the magnet 65 and the stator 60 changes, and the magnetic flux acting on the stator 60 from the magnet 65 changes.

[0075] Additionally, a magnetic yoke 55, part of the magnetic yoke assembly 40, is disposed near the stator 60. The magnetic yoke 55 is a component for detecting changes in the magnetic flux exerted on the stator 60 by the magnet 65, and is disposed near the flange portion 61 of the stator 60. As the stator 60 has a pair of first stators 60a and second stators 60b, correspondingly, the magnetic yoke 55 also has a pair of first magnetic yokes 55a and second magnetic yokes 55b. That is, the first magnetic yoke 55a is disposed near the first flange portion 61a of the first stator 60a, and the second magnetic yoke 55b is disposed near the second flange portion 61b of the second stator 60b.

[0076] A pair of magnetic yokes 55 are located radially outward of the teeth 62 of the stator 60, between the two flanges 61 of the stator 60, and overlap the flanges 61 of the stator 60 with a gap in the axial Z direction. Specifically, the first magnetic yoke 55a is positioned near the side of the second flange 61b of the first flange 61a of the first stator 60a, and the second magnetic yoke 55b is positioned near the side of the first flange 61a of the second flange 61b of the second stator 60b. These magnetic yokes 55 overlap the flanges 61 of the stator 60 within a predetermined range in the circumferential direction.

[0077] Furthermore, the pair of magnetic yokes 55 can also be arranged in a positional relationship whereby the pair of magnetic yokes 55 sandwich the flange portions 61 of the stator 60 from both sides along the Z-axis. That is, the first magnetic yoke 55a can also be arranged near the side opposite to the side of the first flange portion 61a of the first stator 60a, and the second magnetic yoke 55b can also be arranged near the side opposite to the side of the second flange portion 61b of the second stator 60b. The pair of magnetic yokes 55 only need to overlap with the flange portion 61 of the stator 60 near the flange portion 61 within a predetermined range in the circumferential direction. The pair of magnetic yokes 55 can be arranged between the first flange portion 61a and the second flange portion 61b, or they can be arranged in a positional relationship whereby the pair of magnetic yokes 55 sandwich the first flange portion 61a and the second flange portion 61b from both sides along the Z-axis.

[0078] Thus, by positioning the magnetic yokes 55 near the flange 61, a pair of magnetic yokes 55 can detect changes in magnetic flux corresponding to changes in the relative positions of the pair of stators 60 and magnets 65. That is, the magnetic yokes 55 can detect changes in magnetic flux exerted on the stator 60 by the magnets 65 when the short shaft 87 rotates slightly relative to the first pinion 88a.

[0079] Furthermore, a Hall effect IC 50 is disposed between the two magnetic yokes 55. The Hall effect IC 50 is disposed between the magnetic yokes 55 at a position separated from the portion of the magnetic yokes 55 located near the flange 61 of the stator 60. That is, the Hall effect IC 50 is held between the first magnetic yoke 55a and the second magnetic yoke 55b of the magnetic yokes 55. An adhesive layer 56 is filled between the first magnetic yoke 55a and the second magnetic yoke 55b and the Hall effect IC 50. The Hall effect IC 50 is fixed to the first magnetic yoke 55a and the second magnetic yoke 55b via the adhesive layer 56.

[0080] The Hall IC 50 includes a Hall element (not shown) that detects changes in magnetic flux detected by the yokes 55, and an output circuit (not shown) that converts the output voltage from the Hall element into a digital electrical signal based on the change in magnetic flux. Thus, the Hall IC 50 can detect changes in magnetic flux density acting on the two yokes 55, convert the detected change in magnetic flux density into an electrical signal, and output it as an electrical signal. Furthermore, magnetic sensors employing magnetoresistive or tunneling magnetoresistive effects can be used instead of the Hall IC 50. In short, any sensor capable of outputting an electrical signal that can reproduce the change in magnetic flux density between the yokes 55 is acceptable.

[0081] like Figure 2As shown, magnet 65 is mounted to short shaft 87 using a first sleeve 67. The first sleeve 67 is a cylindrical component, and is mounted to short shaft 87 by pressing short shaft 87 into the first sleeve 67. Magnet 65 is fixed to the outer circumferential surface of the first sleeve 67, for example, by adhesive, thereby allowing magnet 65 to rotate integrally with short shaft 87.

[0082] like Figure 2 As shown, the stator 60 is mounted to the first pinion 88a using a second sleeve 63 and a bracket 64. The second sleeve 63 is a cylindrical component, and it is mounted to the first pinion 88a by pressing the first pinion 88a into the second sleeve 63. The bracket 64 is also a cylindrical component, integrally formed with the second sleeve 63. Therefore, the bracket 64 is mounted to the first pinion 88a along with the second sleeve 63 by mounting the second sleeve 63 to the first pinion 88a.

[0083] The bracket 64, which is mounted on the first pinion 88a using the second sleeve 63, is supported by the second sleeve 63, thereby being positioned from the first pinion 88a toward the short shaft 87 and radially outward of the short shaft 87. Furthermore, the bracket 64 is positioned axially in the Z direction at the same location as the magnet 65, and radially outward of the magnet 65.

[0084] The stator 60 is mounted on a bracket 64 configured in this manner. Specifically, the stator 60 of each of the first stator 60a and the second stator 60b is mounted on the bracket 64 such that the teeth 62 are located radially inside the bracket 64 and the flanges 61 protrude radially outward from the inner side of the bracket 64. Thus, the first stator 60a and the second stator 60b, as a pair of stators 60, are both axially positioned at the same location as the magnet 65, and radially outward from the magnet 65.

[0085] Furthermore, the first stator 60a and the second stator 60b are mounted on a bracket 64 that is integrally formed with the second sleeve 63 mounted on the first pinion 88a, thus enabling them to rotate integrally with the first pinion 88a. As described above, the magnet 65 is fixed to the short shaft 87, and the stator 60 is fixed to the first pinion 88a, thereby the magnet 65 and the stator 60 are arranged together with the short shaft 87 and the first pinion 88a inside the housing 20.

[0086] When the short shaft 87 and the first pinion 88 rotate relative to each other due to the slight twisting of the torsion bar 87a, the magnet 65 and the stator 60 also rotate relative to each other. The change in magnetic flux acting on the stator 60 at this time is detected by the magnetic yoke 55.

[0087] The Hall IC 50, which converts the change in magnetic flux detected by the magnetic yoke 55 into an electrical signal, is connected to the circuit board 52 via a lead frame 51. The magnetic yoke assembly 40 mounts the sensor housing 41 onto the housing 20, thereby positioning the magnetic yoke 55 and Hall IC 50, which are located inside the sensor housing 41, in the desired positions.

[0088] Figure 5 yes Figure 3 The diagram shows a cross-sectional view of the housing 20. The first housing 20a of the housing 20 has a sealing member abutment 25 radially outward of the receiving portion 26, which opens radially outward from the inner circumferential surface 21 of the housing 20. That is, the sealing member abutment 25 is radially disposed on the opposite side of the receiving portion 26 from the side where the inner circumferential surface 21 of the housing 20 is located; in other words, the sealing member abutment 25 is disposed on the magnetic yoke assembly 40 (see reference 40). Figure 3 The part that is inserted relative to the storage part 26 in the insertion direction is closer to the entrance side of the storage part 26.

[0089] The sealing member abutment portion 25 is also formed in the same way as the receiving portion 26, into a hole-like shape that opens radially, but the size of the hole is larger than that of the receiving portion 26. Therefore, the receiving portion inner wall 27, which serves as the inner wall of the receiving portion 26, and the sealing member abutment portion 25 are formed in such a way that they have a height difference from each other.

[0090] Figure 6 It is along Figure 3 The image shows a top view of the magnetic yoke assembly 40 as seen from the AA direction. The sensor housing 41 of the magnetic yoke assembly 40 is made of resin material and has a flange 42, a connector 43, a sealing component mounting portion 44, and a protrusion 45. The flange 42 serves as a plate-like portion for mounting the sensor housing 41 to the housing 20. Bolt holes (not shown) are formed in the flange 42 for mounting bolts (not shown) to mount the magnetic yoke assembly 40 to the housing 20 to pass through. The sensor housing 41 is mounted to the housing 20 by mounting the flange 42 to the radially outer end face of the portion forming the receiving portion 26 within the housing 20 using the mounting bolts.

[0091] With the yoke assembly 40 installed in the housing 20, the connector portion 43 is positioned radially outward relative to the flange portion 42. The connector portion 43 has a terminal extending from the Hall IC 50 of the yoke assembly 40 disposed on its inner side, serving as the portion connecting the terminal extending from the Hall IC 50 to an external terminal. By connecting the terminal extending from the Hall IC 50 to the external terminal via the connector portion 43, the yoke assembly 40 can electrically connect the torque sensor 10 to the ECU 100.

[0092] With the magnetic yoke assembly 40 installed in the housing 20, the sealing member arrangement portion 44 and the protrusion 45 are arranged radially inward relative to the flange portion 42. Specifically, the sealing member arrangement portion 44 is arranged close to the flange portion 42 relative to the protrusion 45 in the longitudinal direction Y, and the protrusion 45 is arranged on the opposite side of the flange portion 42 relative to the sealing member arrangement portion 44 in the longitudinal direction Y. The sealing member arrangement portion 44 is capable of accommodating the O-ring 70 (described later). Figure 7 The torque sensor 10 of the first embodiment can be used in either a waterproof or non-waterproof configuration. When used in a waterproof configuration, an O-ring 70 is provided in the sealing component configuration section 44. When used in a non-waterproof configuration, an O-ring 70 is not provided in the sealing component configuration section 44.

[0093] The protrusion 45 protrudes from the position of the sealing member placement portion 44 in the longitudinal direction Y toward the opposite side of the flange portion 42. A space is formed inside the protrusion 45, and the Hall IC 50 of the magnetic yoke assembly 40 is disposed inside the protrusion 45 in the sensor housing 41.

[0094] The protrusion 45 is formed such that, when the sensor housing 41 is viewed along the axial direction Z, the end portion 45a on the opposite side of the side where the sealing member arrangement portion 44 is located in the longitudinal direction Y has a curved shape that is recessed towards the side where the sealing member arrangement portion 44 is located in the longitudinal direction Y. The curved shape of the end portion 45a of the protrusion 45 is such that, with the magnetic yoke assembly 40 mounted on the housing 20, the center of the arc and the short axis 87 (see reference) are aligned. Figure 2 ), First pinion 88a (refer to) Figure 2 The axis of the circle is essentially the same as the arc shape.

[0095] The width of the protrusion 45 in the width direction X and the width in the axial direction Z are both smaller than those of the sealing member arrangement portion 44. That is, when the sensor housing 41 is viewed along the length direction Y, the size of the protrusion 45 is smaller than that of the sealing member arrangement portion 44 over its entire circumference. In other words, when viewed in the insertion direction in which the protrusion 45 is inserted into the receiving portion 26 of the housing 20, the outline shape of the protrusion 45 is smaller than the outline shape of the sealing member arrangement portion 44. As a result, the protrusion 45 has a height difference relative to the sealing member arrangement portion 44.

[0096] Furthermore, an inclined connecting portion 48 is provided between the sealing member arrangement portion 44 and the protrusion 45 in the sensor housing 41. The inclined connecting portion 48 is inclined relative to the insertion direction in which the protrusion 45 is inserted into the receiving portion 26 of the housing 20, and the sealing member arrangement portion 44, which is formed to have a height difference, is connected to the protrusion 45. That is, the inclined connecting portion 48 is inclined relative to the length direction Y as it moves from the side where the sealing member arrangement portion 44 is located toward the side where the protrusion 45 is located, in a direction that reduces the distance from the protrusion 45 in the width direction X and the distance from the protrusion 45 in the axial direction Z.

[0097] Furthermore, the protrusion 45 has a plurality of compression ribs 47 on its outer peripheral surface 46. The compression ribs 47 protrude from the outer peripheral surface 46 of the protrusion 45 and are formed in a rib-like shape extending along the length direction Y from a position near the sealing member mounting portion 44. The sensor housing 41 is made of resin material, and the sealing member mounting portion 44, the protrusion 45, the inclined connecting portion 48, and the compression ribs 47 are integrally formed. Specifically, the end of the compression rib 47 on the side where the sealing member mounting portion 44 is located in the insertion direction into the receiving portion 26 of the housing 20 (where the protrusion 45 is inserted) is connected to the inclined connecting portion 48, and the compression rib 47 extends along the length direction Y from the position of the inclined connecting portion 48. The height of the compression rib 47 from the outer peripheral surface 46 of the protrusion 45 is lower than the height of the sealing member mounting portion 44 from the outer peripheral surface 46 of the protrusion 45. Additionally, although the width of the compression rib 47 is wider than its height, it is relatively narrow.

[0098] Furthermore, the length Lr of the compression rib 47 in the longitudinal direction Y from the sealing member arrangement portion 44 is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48. That is, the length Lr of the compression rib 47 from the position of the sealing member arrangement portion 44 in the insertion direction of the protrusion 45 to the end on the opposite side of the side where the sealing member arrangement portion 44 is located in the compression rib 47 is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48 in the insertion direction of the protrusion 45. In this case, the combined length Lp of the protrusion 45 and the inclined connecting portion 48 becomes the length of the longest portion of the protrusion 45 in the longitudinal direction Y from the position of the sealing member arrangement portion 44.

[0099] Multiple compression ribs 47 are disposed on the protrusion 45, but the total length Lr of all the compression ribs 47 disposed on the protrusion 45 is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48. In addition, the multiple compression ribs 47 disposed on the protrusion 45 are formed with substantially the same length Lr from the position of the sealing member placement portion 44.

[0100] Figure 7This is a schematic diagram showing the state in which the protrusion 45 of the magnetic yoke assembly 40 is housed in the housing portion 26 of the housing 20. Figure 8 yes Figure 7 The BB cross-sectional view. When the magnetic yoke assembly 40 is installed on the housing 20, the protrusion 45 of the sensor housing 41 of the magnetic yoke assembly 40 is inserted into the housing 26 with the protrusion 45 protruding from the flange 42 toward the side where the housing 20 is located in the longitudinal direction Y. After the protrusion 45 of the sensor housing 41 of the magnetic yoke assembly 40 is inserted into the housing 26 and stored in the housing 26, the flange 42 of the sensor housing 41 is installed on the housing 20 by mounting bolts (not shown). Thus, the Hall IC 50 (see reference) of the magnetic yoke assembly 40 is stored in the housing 26 of the housing 20 with the protrusion 45 of the sensor housing 41 inside the protrusion 45. Figure 3 The housing 20 is installed in the desired position.

[0101] With the protrusion 45 of the sensor housing 41 housed within the receiving portion 26 of the housing 20, a plurality of compression ribs 47 disposed on the outer peripheral surface 46 of the protrusion 45 abut against the inner wall 27 of the receiving portion, which serves as the inner wall of the receiving portion 26. That is, the height of the plurality of compression ribs 47 disposed on the outer peripheral surface 46 of the protrusion 45 from the outer peripheral surface 46 is equal to the distance between the outer peripheral surface 46 of the protrusion 45 and the inner wall 27 of the receiving portion, and slightly higher than the distance between the outer peripheral surface 46 of the protrusion 45 and the inner wall 27 of the receiving portion. Therefore, the plurality of compression ribs 47 disposed on the outer peripheral surface 46 of the protrusion 45 abut against the inner wall 27 of the receiving portion.

[0102] At this time, since the sensor housing 41 is made of resin material, the compression ribs 47 are slightly flattened by elastic deformation and abut against the inner wall 27 of the receiving portion. In the first embodiment, the compression ribs 47 are respectively disposed on the outer peripheral surfaces 46 of both sides of the protrusion 45 in the axial direction Z and on both sides of the outer peripheral surfaces 46 of the protrusion 45 in the width direction X, which is orthogonal to both the axial direction Z and the length direction Y. In detail, in the first embodiment, the compression ribs 47 are disposed at two locations on both sides of the outer peripheral surface 46 of the protrusion 45 in the axial direction Z, and at one location at each end of the width direction X, for a total of six compression ribs 47 abut against the inner wall 27 of the receiving portion.

[0103] The compression rib 47, which abuts against the inner wall 27 of the receiving portion, has a length Lr in the insertion direction of the protrusion 45 into the receiving portion 26, which is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48 in the insertion direction. Therefore, the compression rib 47 abuts against the inner wall 27 of the receiving portion with a length shorter than Lp of the combined length of the protrusion 45 and the inclined connecting portion 48 in the insertion direction of the protrusion 45 into the receiving portion 26. That is, the abutment length Lc of the compression rib 47 relative to the inner wall 27 of the receiving portion when the protrusion 45 of the sensor housing 41 of the magnetic yoke assembly 40 is received in the receiving portion 26 of the housing 20 is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48.

[0104] Furthermore, the torque sensor 10 of the first embodiment can be used with an O-ring 70 provided in the sealing member arrangement section 44 when it is used in a waterproof configuration, and can be used without an O-ring 70 provided in the sealing member arrangement section 44 when it is used in a non-waterproof configuration. Therefore, when used in a waterproof configuration, the yoke assembly 40 has the protrusion 45 housed inside the storage section 26 with the O-ring 70, which serves as a sealing member, provided in the sealing member arrangement section 44 of the sensor housing 41. The O-ring 70 is a ring-shaped component made of rubber material, so the ring-shaped O-ring 70 is arranged around the entire circumference of the sealing member arrangement section 44 of the sensor housing 41 when the sensor housing 41 is viewed along the length direction Y.

[0105] On the other hand, the housing 20 has a sealing member abutment portion 25 in the insertion direction of the housing 26 closer to the inlet side than the housing 26 when the protrusion 45 is inserted into the housing 26. Therefore, when the protrusion 45 of the sensor housing 41 is housed in the housing 26 of the housing 20, the O-ring 70 disposed in the sealing member placement portion 44 of the sensor housing 41 abuts against the inner peripheral surface of the sealing member abutment portion 25.

[0106] The O-ring 70 of the magnetic yoke assembly 40 is disposed in the sealing member arrangement portion 44 of the sensor housing 41 as described above. At a position closer to the inlet side of the receiving portion 26 than the receiving portion 26 in the insertion direction when the protrusion 45 is inserted into the receiving portion 26, the O-ring 70 abuts against both the sealing member arrangement portion 44 of the sensor housing 41 and the sealing member contact portion 25 of the housing 20. Thus, the O-ring 70 ensures a tight seal between the sensor housing 41 and the housing 20 at this position closer to the inlet side of the receiving portion 26 in the insertion direction when the protrusion 45 is inserted into the receiving portion 26.

[0107] Figure 9This is an exploded perspective view of the short shaft 87, the first pinion 88a, and the torque sensor 10. An insertion hole 881 is formed at the end of the first pinion 88a on one side where the short shaft 87 is located, serving as a hole for inserting the short shaft 87. A protrusion / recess 882 is formed on the inner circumferential surface of the insertion hole 881 in the first pinion 88a. The protrusion / recess 882 is alternately arranged in the circumferential direction of the insertion hole 881, with a plurality of protrusions 882b protruding radially inward toward the insertion hole 881 and a plurality of recesses 882a recessed radially outward toward the insertion hole 881. The axial length of these protrusions 882b and recesses 882a in the first pinion 88a is the same as the axial length of the insertion hole 881.

[0108] On the other hand, the short shaft 87 has an insertion portion 871 that serves as a portion of the insertion hole 881 for inserting the first pinion 88a into the short shaft 87. The insertion portion 871 of the short shaft 87 is disposed at the end of the short shaft 87 on the side where the first pinion 88a is located. At the insertion portion 871 of the short shaft 87, a protrusion 872 corresponding to the protrusion 882 formed in the insertion hole 881 of the first pinion 88a is formed on the outer peripheral surface of the insertion portion 871. That is, the protrusion 872 formed in the insertion portion 871 has a plurality of recesses 872a that are recessed inward toward the radial direction of the insertion portion 871 and a plurality of protrusions 872b that are protruding outward toward the radial direction of the insertion portion 871, which are alternately arranged in the circumferential direction of the insertion portion 871.

[0109] The number of recesses 872a and protrusions 872b in the insertion portion 871 formed on the short shaft 87 is the same as the number of recesses 882a and protrusions 882b in the insertion hole 881 formed on the first pinion 88a. Furthermore, the number of recesses 882a and protrusions 882b in the insertion hole 881 formed on the first pinion 88a and the number of recesses 872a and protrusions 872b in the insertion portion 871 formed on the short shaft 87 are the same as the number of recesses 872a and protrusions 872b in the first stator 60a (see reference). Figure 4 The number of first teeth 62a and second stator 60b (refer to) Figure 4 The number of the second teeth 62b is the same as that of the first teeth.

[0110] In this embodiment, the number of recesses 882a and protrusions 882b in the insertion hole 881 formed on the first pinion 88a are both eight, and the number of recesses 872a and protrusions 872b in the insertion portion 871 formed on the short shaft 87 are also both eight. Furthermore, the number of first teeth 62a in the first stator 60a and the number of second teeth 62b in the second stator 60b are also both eight.

[0111] A protrusion 882 is formed in the insertion hole 881 of the first pinion 88a, and a protrusion 872 is formed in the insertion portion 871 of the short shaft 87. Therefore, when the insertion portion 871 of the short shaft 87 is inserted into the insertion hole 881 of the first pinion 88a, the protrusion 872 of the insertion portion 871 of the short shaft 87 enters the protrusion 882 of the insertion hole 881 of the first pinion 88a. That is, when the insertion portion 871 of the short shaft 87 is inserted into the insertion hole 881 of the first pinion 88a, the protrusion 872b formed in the insertion portion 871 of the short shaft 87 enters the recess 882a formed in the insertion hole 881 of the first pinion 88a, and the protrusion 882b formed in the insertion hole 881 of the first pinion 88a enters the recess 872a formed in the insertion portion 871 of the short shaft 87.

[0112] Here, the size of the protrusion 872b of the insertion portion 871 formed on the short shaft 87 in the circumferential direction is smaller than the size of the recess 882a of the insertion hole 881 formed on the first pinion 88a in the circumferential direction. Similarly, the size of the protrusion 882b of the insertion hole 881 formed on the first pinion 88a in the circumferential direction is smaller than the size of the recess 872a of the insertion portion 871 formed on the short shaft 87 in the circumferential direction.

[0113] Therefore, when the insertion portion 871 of the short shaft 87 is inserted into the insertion hole 881 of the first pinion 88a, the insertion portion 871 of the short shaft 87 is inserted into the insertion hole 881 of the first pinion 88a in such a way that the concave and convex portions 872 of the short shaft 87 and the concave and convex portions 882 of the first pinion 88a do not abut against each other.

[0114] That is, when the insertion portion 871 of the short shaft 87 is inserted into the insertion hole 881 of the first pinion 88a, the protrusions 872b formed in the insertion portion 871 of the short shaft 87 are arranged between adjacent protrusions 882b in the recessed portion 882 of the first pinion 88a in such a way that they do not abut against each other. Therefore, when the insertion portion 871 of the short shaft 87 is inserted into the insertion hole 881 of the first pinion 88a, the recessed portion 872 of the short shaft 87 and the recessed portion 882 of the first pinion 88a transmit torque between the short shaft 87 and the first pinion 88a via the torsion bar 87a in such a way that they do not abut against each other.

[0115] The protrusion 872 of the insertion portion 871 of the short shaft 87, formed in this way, does not abut against the protrusion 882 of the insertion hole 881 of the first pinion 88a during normal rotation, but abuts against the torsion bar 87a when the torsion angle is greater than a predetermined angle. That is, when the torsion angle of the torsion bar 87a is greater than a predetermined torsion angle, the protrusion 872 of the insertion portion 871 of the short shaft 87 abuts against the protrusion 882 of the insertion hole 881 of the first pinion 88a, thereby preventing the relative rotation angle difference between the short shaft 87 and the first pinion 88a in the circumferential direction from further increasing. Thus, the torsion angle of the torsion bar 87a is prevented from exceeding the torsion angle that would damage the torsion bar 87a, and damage to the torsion bar 87a caused by the torsion angle becoming too large is suppressed.

[0116] The torque sensor 10 has a magnet 65 and a stator 60 respectively disposed on a short shaft 87 and a first pinion 88a. That is, the magnet 65 is disposed on the short shaft 87, and the stator 60 is disposed on the first pinion 88a. The magnet 65 disposed on the short shaft 87 is mounted on the short shaft 87 with its circumferential orientation such that the boundary between the S pole 66s and the N pole 66n of the magnet 65 is located at the circumferential center of the protrusion 872b formed in the insertion portion 871 of the short shaft 87.

[0117] The stator 60, disposed on the first pinion 88a, is mounted in a circumferential orientation such that the circumferential position of the recess 882a or protrusion 882b formed in the insertion hole 881 of the first pinion 88a is the same as the circumferential position of the tooth 62 of the stator 60. For example, the stator 60 is mounted on the first pinion 88a in such an orientation that the circumferential position of the recess 882a formed in the insertion hole 881 of the first pinion 88a is the same as the circumferential position of the first tooth 62a of the first stator 60a, and the circumferential position of the protrusion 882b formed in the insertion hole 881 is the same as the circumferential position of the second tooth 62b of the second stator 60b.

[0118] Furthermore, the positional relationship between the recess 872 of the insertion portion 871 and the tooth 62 of the stator 60 can also be reversed. That is, the stator 60 can also be mounted on the first pinion 88a in such an orientation that the circumferential position of the recess 882a in the insertion portion 871 is the same as the circumferential position of the second tooth 62b, and the circumferential position of the protrusion 882b is the same as the circumferential position of the first tooth 62a.

[0119] At this time, the number of recesses 882a and protrusions 882b in the insertion hole 881 formed in the first pinion 88a is set to be the same as the number of first teeth 62a and second teeth 62b of the first stator 60a and the second stator 60b. Therefore, when the stator 60 is mounted on the first pinion 88a, by aligning any one of the multiple teeth 62 of the stator 60 with the circumferential position of the recess 882a or protrusion 882b formed in the insertion hole 881 of the first pinion 88a, circumferential phase alignment when mounting the stator 60 on the first pinion 88a can be easily achieved. As a result, assembly time can be reduced when the stator 60 is mounted with circumferential phase alignment relative to the first pinion 88a.

[0120] Furthermore, the number of recesses 882a and protrusions 882b formed in the insertion hole 881 of the first pinion 88a may not be the same as the number of first teeth 62a and second teeth 62b of the first stator 60a and the second stator 60b. For example, the number of recesses 882a and protrusions 882b formed in the insertion hole 881 of the first pinion 88a and the number of teeth 62 of the stator 60 may be configured such that any one of the recesses 882a and protrusions 882b formed in the insertion hole 881 and the number of teeth 62 of the stator 60 is a multiple of the other. Even when the number of recesses 882a and protrusions 882b formed in the insertion hole 881 is different from the number of teeth 62 on the stator 60, by setting one to be a multiple of the other, the circumferential phase alignment when mounting the stator 60 on the first pinion 88a can be easily achieved by aligning the circumferential position of any tooth 62 with the recess 882a or protrusion 882b.

[0121] With the magnet 65 and stator 60 respectively arranged on the short shaft 87 and the first pinion 88a as described above, the insertion portion 871 of the short shaft 87 is inserted into the insertion hole 881 of the first pinion 88a and connected via the torsion bar 87a. Thus, the short shaft 87 and the first pinion 88a are connected such that the boundaries of the magnetic poles 66 of the magnet 65 arranged on the short shaft 87 are aligned circumferentially with the center of the teeth 62 of the stator 60 arranged on the first pinion 88a.

[0122] Next, the function of the steering system 80 will be explained. When the vehicle equipped with the steering system 80 is in motion, with the steering wheel 81 operated, the steering force applied to the steering wheel 81 is transmitted from the steering wheel 81 to the steering shaft 82. The steering force transmitted to the steering shaft 82 is transmitted as a steering torque from the steering shaft 82 to the intermediate shaft 85, and from the intermediate shaft 85 to the first pinion 88a via the short shaft 87. As a result, the steering gear 88 with the first pinion 88a converts the rotational motion transmitted from the first pinion 88a into the linear motion of the rack 88b, thereby actuating the tie rod 89.

[0123] Furthermore, the steering device 80 of the first embodiment includes an electric motor 102 that generates an auxiliary steering torque to assist the driver in steering. The electric motor 102 generates the auxiliary steering torque based on the steering torque detected by a torque sensor 10 disposed between a short shaft 87 and a first pinion 88a.

[0124] The torque sensor 10 detects the steering torque applied to the short shaft 87 based on the angle of relative rotation between the short shaft 87 and the first pinion 88a. Specifically, the short shaft 87 and the first pinion 88a are connected via a torsion bar 87a, so when steering torque is applied to the short shaft 87, it is transmitted between the short shaft 87 and the first pinion 88a via the torsion bar 87a. At this time, the torsion bar 87a is slightly twisted, causing the short shaft 87 and the first pinion 88a to rotate relative to each other.

[0125] In the torque sensor 10, the magnet 65 rotates relative to the stator 60 as the short shaft 87 rotates relative to the first pinion 88a. As described above, the torque sensor 10 uses the yoke 55 to detect the change in magnetic flux acting on the stator 60 when the magnet 65 rotates relative to the stator 60, converts this change into an electrical signal using the Hall IC 50, and transmits it to the ECU 100. That is, the torque sensor 10 detects the change in magnetic flux acting on the stator 60 from the magnet 65 using the yoke 55 and the Hall IC 50, thereby detecting the steering torque applied to the short shaft 87, and transmits the detected steering torque as an electrical signal to the ECU 100.

[0126] The ECU 100 operates the electric motor 102 based on the electrical signal transmitted from the torque sensor 10, causing the electric motor 102 to generate auxiliary steering torque. Specifically, the electrical signal transmitted from the Hall IC 50 of the torque sensor 10 to the ECU 100 changes based on the variation of the steering torque T acting between the minor shaft 87 and the first pinion 88a. Therefore, the ECU 100 uses the electrical signal transmitted from the Hall IC 50 of the torque sensor 10 as information about the variation of the steering torque T acting on the minor shaft 87 and the first pinion 88a, and adjusts the power value E supplied to the electric motor 102 based on the electrical signal transmitted from the Hall IC 50, causing the electric motor 102 to generate auxiliary steering torque.

[0127] That is, the ECU 100 obtains the steering torque T signal from the torque sensor 10, the vehicle speed signal V from the vehicle speed sensor 101, and then obtains the operation information M of the electric motor 102 from the rotation detection device provided on the electric motor 102. Based on the aforementioned operation information M, steering torque T, and vehicle speed signal V, the electric motor 102 generates auxiliary steering torque. The auxiliary steering torque generated by the electric motor 102 is transmitted to the second pinion 88c. The steering gear 88 with the second pinion 88c converts the rotational motion transmitted from the second pinion 88c into the linear motion of the rack 88b. Thus, the steering force applied by the driver to the steering wheel 81 is assisted by the auxiliary steering torque generated by the electric motor 102.

[0128] Thus, when the torque sensor 10, which detects the driver's steering torque, is used in a waterproof configuration, an O-ring 70 is disposed between the magnetic yoke assembly 40 and the housing 20 to ensure waterproofing. The O-ring 70 abuts against both the inner circumferential surface of the sealing member contact portion 25 of the housing 20 and the outer circumferential surface of the sealing member arrangement portion 44 of the magnetic yoke assembly 40, thereby ensuring a tight seal and preventing water from entering the receiving portion 26 from the outside of the housing 20. The O-ring 70 is made of an elastic component and elastically deforms to flatten itself when it abuts against the sealing member contact portion 25 of the housing 20 and the sealing member arrangement portion 44 of the magnetic yoke assembly 40, thereby ensuring a tight seal.

[0129] By inserting the protrusion 45 of the magnetic yoke assembly 40 into the receiving portion 26 of the housing 20 with the O-ring 70 disposed in the sealing member configuration portion 44 of the magnetic yoke assembly 40, the O-ring 70 is configured to abut against both the magnetic yoke assembly 40 and the housing 20. Therefore, if there is an installation error between the magnetic yoke assembly 40 and the housing 20, the flattening method of the O-ring 70 will also change according to the installation error, and thus the sealing performance of the O-ring 70 will also change, and depending on the situation, the sealing performance of the O-ring 70 may decrease.

[0130] Thus, in the event of an installation error between the magnetic yoke assembly 40 and the housing 20, the sealing performance of the O-ring 70 may be reduced. Therefore, a compression rib 47 is provided on the outer peripheral surface 46 of the protrusion 45 of the sensor housing 41 of the magnetic yoke assembly 40. By providing the compression rib 47 on the protrusion 45 of the sensor housing 41, the magnetic yoke assembly 40 can be installed in the housing 20 while simultaneously positioning the magnetic yoke assembly 40 relative to the housing 20, when the protrusion 45 of the magnetic yoke assembly 40 is housed in the housing portion 26 of the housing 20.

[0131] That is, when the protrusion 45 of the magnetic yoke assembly 40 is housed in the housing portion 26 of the housing 20, the pressing rib 47 can abut against the inner wall 27 of the housing portion, causing the portion of the pressing rib 47 and the protrusion 45 in which the pressing rib 47 is located to deform slightly while the protrusion 45 is housed in the housing portion 26. In other words, the magnetic yoke assembly 40 can be installed on the housing 20 while the protrusion 45 of the magnetic yoke assembly 40 is pressed into the housing portion 26 of the housing 20. Therefore, the positioning of the magnetic yoke assembly 40 relative to the housing 20 is possible.

[0132] However, when the compressive force exerted by the housing 20 on the protrusion 45 of the magnetic yoke assembly 40 is large, the deformation of the protrusion 45 increases. With the deformation of the protrusion 45, the inclined connecting portion 48 and the sealing component placement portion 44 may also deform. When the sealing component placement portion 44 deforms, the pressure exerted by the sealing component placement portion 44 on the O-ring 70 disposed therein changes. Therefore, the flattening method of the O-ring 70 between the sealing component placement portion 44 of the magnetic yoke assembly 40 and the sealing component abutment portion 25 of the housing 20 also changes, potentially making it difficult to ensure a tight seal.

[0133] In contrast, in the first embodiment, the contact length Lc of the compression rib 47 of the protrusion 45 disposed on the magnetic yoke assembly 40 with respect to the inner wall 27 of the housing portion in the longitudinal direction Y is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48 in the longitudinal direction Y. Therefore, the range of deformation of the protrusion 45 when the compression rib 47 contacts the inner wall 27 of the housing portion can be reduced. As a result, deformation of the sealing member arrangement portion 44, which is associated with the deformation of the protrusion 45 due to the contact of the compression rib 47 with the inner wall 27 of the housing portion, can be suppressed, and the flattening of the O-ring 70 disposed between the sealing member arrangement portion 44 of the magnetic yoke assembly 40 and the sealing member contact portion 25 of the housing 20 can be made uniform. Therefore, the O-ring 70 can ensure the sealing between the sealing member arrangement portion 44 and the O-ring 70, and between the sealing member contact portion 25 and the O-ring 70, throughout the entire circumference of the O-ring 70, and can ensure the sealing uniformly throughout the entire circumference of the O-ring 70.

[0134] Figure 10 This is a schematic diagram of the magnetic yoke assembly 40 and the storage portion 26 when the torque sensor 10 is used in a non-waterproof configuration. When the torque sensor 10 is used in a non-waterproof configuration, as... Figure 10 As shown, without the O-ring 70 being configured in the sealing component configuration section 44, the protrusion 45 of the magnetic yoke assembly 40 is housed in the housing section 26 of the housing 20. Therefore, the torque sensor 10 can use components common to both waterproof and non-waterproof specifications, thus adapting to both specifications.

[0135] Even when the torque sensor 10 is used in a non-waterproof configuration as described above, when the protrusion 45 of the magnetic yoke assembly 40 is housed in the housing portion 26 of the housing 20, the compression rib 47 disposed on the protrusion 45 abuts against the inner wall 27 of the housing portion. Thus, the magnetic yoke assembly 40 is positioned relative to the housing 20. Therefore, the magnetic yoke assembly 40 is mounted on the housing 20 with the magnetic yoke 55 disposed inside the sensor housing 41 positioned relative to the stator 60 mounted on the first pinion 88a.

[0136] That is, the compression ribs 47 disposed on the protrusion 45 are respectively disposed on the outer peripheral surfaces 46 on both sides of the protrusion 45 in the axial direction Z and the outer peripheral surfaces 46 on both sides of the protrusion 45 in the width direction X. As a result, the magnetic yoke assembly 40 is installed in a state in which it is positioned relative to the housing 20 in both the axial direction Z and the width direction X. Therefore, the magnetic yoke 55 disposed on the inner side of the sensor housing 41 is positioned relative to the stator 60 mounted on the first pinion 88a in both the axial direction Z and the width direction X.

[0137] Therefore, the magnetic yoke 55 is configured such that the distance in the axial Z direction between it and the flange 61 of the stator 60 is close to the distance set in the design of the torque sensor 10, and the relative position of the stator 60 with respect to the flange 61 in the width direction X is close to the relative position set in the design of the torque sensor 10. Thus, the torque sensor 10 can suppress the deviation of the magnetic flux detected by the magnetic yoke 55 and can appropriately detect the steering torque.

[0138] Furthermore, the sensor housing 41 of the magnetic yoke assembly 40 has an inclined connecting portion 48 between the sealing member mounting portion 44 and the protrusion 45. Therefore, when using the torque sensor 10 with waterproof specifications, the O-ring 70 can be positioned on the sealing member mounting portion 44 while being guided by the inclined connecting portion 48.

[0139] As described above, in the torque sensor 10 of the first embodiment, a sealing member configuration portion 44 is provided in the yoke assembly 40, which allows for the configuration of an O-ring 70 as a sealing member. Therefore, when the torque sensor 10 is used in a waterproof configuration, by configuring the O-ring 70 in the sealing member configuration portion 44 and housing the protrusion 45 of the yoke assembly 40 within the housing portion 26 of the housing 20, the O-ring 70 ensures a tight seal between the sensor housing 41 and the housing 20. Furthermore, when the torque sensor 10 is used in a non-waterproof configuration, the O-ring 70 is not configured in the sealing member configuration portion 44, and the protrusion 45 of the yoke assembly 40 is housed within the housing portion 26 of the housing 20. Thus, even in a non-waterproof configuration, a yoke assembly 40 with the same shape as that used in a waterproof configuration can be used.

[0140] Furthermore, since an inclined connecting portion 48 is provided between the sealing member placement portion 44 and the protrusion 45 of the magnetic yoke assembly 40, the O-ring 70 can be placed on the sealing member placement portion 44 while being guided by the inclined connecting portion 48. At this time, the O-ring 70 is placed on the sealing member placement portion 44 from the side of the compression rib 47 via the outer side of the compression rib 47. However, since the end of the compression rib 47 on the side where the sealing member placement portion 44 is located is connected to the inclined connecting portion 48, the O-ring 70 will not get stuck between the compression rib 47 and the sealing member placement portion 44 and can be placed on the sealing member placement portion 44. Therefore, the assemblability when placing the O-ring 70 on the sealing member placement portion 44 can be improved.

[0141] Therefore, by sharing the magnetic yoke assembly 40 in both waterproof and non-waterproof versions of the torque sensor 10, the increase in the number of parts can be suppressed, thereby reducing manufacturing costs. Furthermore, the assemblability of the O-ring 70 can be improved, facilitating assembly operations and further reducing manufacturing costs. As a result, it is possible to suppress the increase in manufacturing costs while simultaneously achieving both waterproof and non-waterproof specifications.

[0142] In Patent Document 1, the O-ring used as a seal is elastic and flattens when the cylindrical part is inserted into the mounting hole of the housing, thereby ensuring a seal. However, during the installation of the component with the O-ring and the housing into which the component is inserted, installation errors may occur. In the event of these installation errors, the flattening of the O-ring may vary. As described above, in ensuring waterproofness through the O-ring, individual variations in the flattening of the O-ring can lead to a decrease in its sealing performance. Therefore, there is room for improvement regarding the flattening of the O-ring used as a seal.

[0143] In contrast, in the torque sensor 10 of the first embodiment, when the O-ring 70 is disposed in the sealing member placement portion 44 for waterproofing, the protrusion 45 of the magnetic yoke assembly 40 has multiple compression ribs 47 on its outer peripheral surface 46 that abut against the inner wall 27 of the storage portion 26, which is the inner wall of the storage portion 26 of the housing 20. Therefore, the protrusion 45 can be stored in the storage portion 26 while positioning the protrusion 45 relative to the storage portion 26. In addition, the abutment length Lc of the compression rib 47 relative to the inner wall 27 of the storage portion is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48. Therefore, deformation of the protrusion 45 caused by the abutment of the compression rib 47 against the inner wall 27 of the storage portion can be suppressed, and the compression rib 47 can abut against the inner wall 27 of the storage portion. Therefore, the flattening of the O-ring 70, which is disposed as a sealing component in the sealing component placement section 44 of the magnetic yoke assembly 40, can be made uniform, thus ensuring the sealing performance of the O-ring 70 uniformly throughout its entire circumference. As a result, the sealing performance of the O-ring 70 can be improved.

[0144] Furthermore, the length Lr of the compression rib 47 from the position of the sealing member arrangement portion 44 in the insertion direction of the protrusion 45 relative to the housing portion 26 of the housing 20 to the end opposite to the side where the sealing member arrangement portion 44 is located in the compression rib 47 is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48 in the same direction. Therefore, the abutment length Lc of the compression rib 47 relative to the inner wall 27 of the housing portion can be shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48. As a result, deformation of the protrusion 45 caused by the abutment of the compression rib 47 against the inner wall 27 of the housing portion can be suppressed, and the flattening of the O-ring 70 disposed in the sealing member arrangement portion 44 of the magnetic yoke assembly 40 can be uniformly achieved by the abutment of the compression rib 47 against the inner wall 27 of the housing portion. As a result, the sealing performance of the O-ring 70 can be improved.

[0145] Furthermore, when the torque sensor 10 is used to a waterproof standard, the O-ring 70 is disposed in the sealing member placement portion 44 of the magnetic yoke assembly 40. At a position closer to the inlet side of the receiving portion 26 than the insertion direction of the protrusion 45 relative to the receiving portion 26, the O-ring 70 abuts against both the sealing member contact portion 25 of the housing 20 and the sealing member placement portion 44 of the magnetic yoke assembly 40. Thus, the O-ring 70 can prevent liquids such as water from entering from the outside of the housing 20 towards the inside of the receiving portion 26. As a result, the sealing performance of the O-ring 70 can be effectively utilized, improving the waterproof performance when the torque sensor 10 is used to a waterproof standard.

[0146] Furthermore, the compression ribs 47 are disposed on the outer peripheral surfaces 46 on both sides of the protrusion 45 in the axial Z direction, thus enabling the magnetic yoke assembly 40 to be precisely mounted on the housing 20 in the axial Z direction relative to the housing 20. Therefore, the magnetic yoke 55 disposed on the magnetic yoke assembly 40 can be precisely positioned in the axial Z direction relative to the stator 60 mounted on the first pinion 88a. Consequently, the magnetic yoke 55 is configured such that the distance in the axial Z direction between it and the flange 61 of the stator 60 is close to the distance set in the design of the torque sensor 10. As a result, the torque sensor 10 can suppress deviations in the magnetic flux detected by the magnetic yoke 55 and can appropriately detect the steering torque.

[0147] Furthermore, the compression ribs 47 are disposed on the outer peripheral surfaces 46 on both sides of the protrusion 45 in the width direction X, thus enabling the magnetic yoke assembly 40 to be precisely mounted to the housing 20 in the width direction X relative to the housing 20. Therefore, the magnetic yoke 55 disposed on the magnetic yoke assembly 40 can be precisely positioned relative to the stator 60 mounted on the first pinion 88a in the width direction X. Consequently, the magnetic yoke 55 is configured such that its relative position in the width direction X relative to the flange 61 of the stator 60 is close to the relative position set during the design of the torque sensor 10, allowing the overlap area between the flange 61 of the stator 60 and the magnetic yoke 55 to be of an appropriate size. As a result, the torque sensor 10 can suppress deviations in the magnetic flux detected by the magnetic yoke 55 and can appropriately detect the steering torque.

[0148] [Second Implementation]

[0149] Next, the torque sensor 10 of the second embodiment will be described. The same symbols are used for components identical to those in the first embodiment, and their descriptions are omitted. Hereinafter, the description will focus on the differences from the first embodiment.

[0150] Figure 11 This is a cross-sectional view of the housing 20 of the torque sensor 10 according to the second embodiment. The housing 20 of the torque sensor 10 in the second embodiment, like that in the first embodiment, has a receiving portion 26 and a sealing member abutment portion 25. However, unlike in the first embodiment, the receiving portion 26 has an inner wall 27 with a tapered portion 31 and a flat portion 32.

[0151] The tapered portion 31 of the inner wall 27 of the storage section is inclined relative to the longitudinal direction Y. This inclination direction extends from the side where the sealing member abutment portion 25 is located toward the side where the inner peripheral surface 21 of the housing 20 is located, in a direction that reduces the opening area of ​​the storage section 26 when viewed from the longitudinal direction Y. The flat portion 32 of the inner wall 27 of the storage section is located on the opposite side of the tapered portion 31 from the side where the sealing member abutment portion 25 is located from the longitudinal direction Y, forming an inner wall that is parallel to the longitudinal direction Y.

[0152] Figure 12 This is a top view of the yoke assembly 40 of the torque sensor 10 according to the second embodiment. The yoke assembly 40 of the torque sensor 10 according to the second embodiment has a sensor housing 41, which is the same as that of the first embodiment. The sensor housing 41 has a flange portion 42, a connector portion 43, a sealing member placement portion 44, and a protrusion 45.

[0153] Furthermore, regarding the protrusion 45, a plurality of compression ribs 47 are provided on the outer peripheral surface 46 of the protrusion 45. The compression ribs 47 of the protrusion 45 are different from those in the first embodiment. In the second embodiment, they are arranged from the position of the inclined connecting portion 48 in the length direction Y to the position of the end 45a on the opposite side of the side where the sealing member arrangement portion 44 in the length direction Y of the protrusion 45 is located.

[0154] Here, the end portion 45a of the protrusion 45 is formed with a curved shape, similar to the first embodiment. Therefore, the distance from the inclined connecting portion 48 to the end portion 45a of the protrusion 45 in the length direction Y varies depending on its position in the width direction X, but the compression ribs 47 are arranged from the position of the sealing member arrangement portion 44 to the position of the end portion 45a of the protrusion 45, regardless of their position in the width direction X. Therefore, the length Lr of the plurality of compression ribs 47 arranged on the outer peripheral surface 46 of the protrusion 45 varies in the length direction Y depending on their position in the width direction X.

[0155] Figure 13 This is a schematic diagram showing the state in the second embodiment where the protrusion 45 of the magnetic yoke assembly 40 is housed in the housing portion 26 of the housing 20. When the magnetic yoke assembly 40 is installed in the housing 20, in the second embodiment, similar to the first embodiment, the protrusion 45 of the sensor housing 41 of the magnetic yoke assembly 40 is inserted into and installed in the housing portion 26 in the longitudinal direction Y, protruding from the flange portion 42 towards the side where the housing portion 26 of the housing 20 is located. With the protrusion 45 of the sensor housing 41 housed in the housing portion 26 of the housing 20, a plurality of compression ribs 47 disposed on the outer peripheral surface 46 of the protrusion 45 abut against the inner wall 27 of the housing portion, which serves as the inner wall of the housing portion 26.

[0156] In this second embodiment, the inner wall 27 of the receiving portion 26 has a tapered portion 31 inclined with respect to the longitudinal direction Y and a flat portion 32 formed parallel with respect to the longitudinal direction Y. The tapered portion 31, inclined with respect to the longitudinal direction Y, is inclined in the following direction when the protrusion 45 of the sensor housing 41 is received in the receiving portion 26: as it moves inward from the opening side of the receiving portion 26 toward the insertion direction in which the protrusion 45 is inserted into the receiving portion 26, the distance between the inner wall 27 of the receiving portion and the outer peripheral surface 46 of the protrusion 45 decreases. That is, the tapered portion 31 of the inner wall 27 of the receiving portion becomes such that as it moves inward from the side where the sealing member abutment portion 25 is located toward the inner peripheral surface 21 of the housing 20 (see reference 20) in the longitudinal direction Y. Figure 11 A cone-shaped inner wall that reduces the distance between the inner wall 27 of the storage section and the outer peripheral surface 46 of the protrusion 45 by placing it on one side.

[0157] The flat portion 32 is located further inward than the tapered portion 31 in the insertion direction when the protrusion 45 is inserted into the receiving portion 26. That is, the flat portion 32 is disposed on the inner circumferential surface 21 of the housing 20 relative to the tapered portion 31 in the length direction Y (see reference). Figure 11 (The location is on one side.)

[0158] Furthermore, since the flat portion 32 is formed parallel to the length direction Y, the distance between the inner wall 27 of the receiving portion 26 and the outer peripheral surface 46 of the protrusion 45 is constant when the protrusion 45 of the sensor housing 41 is housed in the receiving portion 26. That is, the flat portion 32 is formed as an inner wall that keeps the distance between the outer peripheral surface 46 of the protrusion 45 and the flat portion 32 constant and is substantially parallel to the outer peripheral surface 46 of the protrusion 45.

[0159] Thus, the distance between the flat portion 32, which is formed parallel to the outer peripheral surface 46 of the protrusion 45, and the outer peripheral surface 46 of the protrusion 45 is the same as the height of the compression rib 47 from the outer peripheral surface 46 of the protrusion 45, and is slightly smaller than the height of the compression rib 47. Therefore, when the protrusion 45 of the sensor housing 41 is housed in the housing portion 26, the compression rib 47 disposed on the outer peripheral surface 46 of the protrusion 45 abuts against the inner wall 27 of the housing portion at the flat portion 32.

[0160] Therefore, in the second embodiment, the abutment length Lc of the compression rib 47 relative to the inner wall 27 of the storage portion becomes the length in the longitudinal direction Y of the flat portion 32 of the inner wall 27 of the storage portion. The flat portion 32 of the inner wall 27 of the storage portion is a part of the inner wall 27 of the storage portion in the longitudinal direction Y, so the abutment length Lc of the compression rib 47 relative to the inner wall 27 of the storage portion, which is the abutment length between the compression rib 47 and the flat portion 32, is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48 of the sensor housing 41.

[0161] In the second embodiment, as described above, the contact length Lc of the compression rib 47 of the protrusion 45 disposed on the magnetic yoke assembly 40 relative to the inner wall 27 of the housing portion in the longitudinal direction Y is also shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48 in the longitudinal direction Y. Therefore, when the compression rib 47 abuts against the inner wall 27 of the housing portion, the range of deformation of the protrusion 45 can be reduced, and the deformation of the sealing member arrangement portion 44 accompanying the deformation of the protrusion 45 due to the contact between the compression rib 47 and the inner wall 27 of the housing portion can be suppressed. As a result, the flattening mode of the O-ring 70 disposed between the sealing member arrangement portion 44 of the magnetic yoke assembly 40 and the sealing member contact portion 25 of the housing 20 can be uniformly made, and the sealing performance of the O-ring 70 can be uniformly ensured throughout the entire circumference of the O-ring 70.

[0162] Furthermore, in the second embodiment, the inner wall 27 of the housing portion 26 of the housing 20 has a tapered portion 31 and a flat portion 32. The flat portion 32 is located further inward than the tapered portion 31 in the insertion direction of the protrusion 45 relative to the housing portion 26. The compression rib 47 disposed on the outer peripheral surface 46 of the protrusion 45 abuts against the inner wall 27 of the housing portion at the flat portion 32. Thus, the compression rib 47 abuts against the inner wall 27 of the housing portion at a position separate from the sealing member arrangement portion 44. Therefore, even if the protrusion 45 deforms due to the compression rib 47 abutting against the inner wall 27 of the housing portion, the deformation of the protrusion 45 is unlikely to affect the sealing member arrangement portion 44. Therefore, the deformation of the sealing member arrangement portion 44 accompanying the deformation of the protrusion 45 due to the compression rib 47 abutting against the inner wall 27 of the housing portion can be suppressed more reliably, and the flattening method of the O-ring 70 disposed in the sealing member arrangement portion 44 of the magnetic yoke assembly 40 can be made uniform. As a result, the sealing performance of the O-ring 70 can be improved.

[0163] Furthermore, the inner wall 27 of the receiving portion has a tapered portion 31 on the side of the flat portion 32 that abuts against the sealing member 25, thus allowing for easy insertion of the protrusion 45 of the magnetic yoke assembly 40 into the receiving portion 26 of the housing 20. That is, when the protrusion 45 is inserted into the receiving portion 26, the tapered portion 31 guides the pressing rib 47 disposed on the outer peripheral surface 46 of the protrusion 45 while pressing the pressing rib 47 into the flat portion 32. This improves the ease of assembly of the magnetic yoke assembly 40 relative to the housing 20 when the pressing rib 47 is provided on the protrusion 45 for positioning the magnetic yoke assembly 40 relative to the housing 20. As a result, the assemblability of the torque sensor 10 is improved.

[0164] [Variation Example]

[0165] Furthermore, in the second embodiment described above, the inner wall 27 of the storage portion 26 has a tapered portion 31 and a flat portion 32, thereby causing the compression rib 47 of the protrusion 45 disposed on the magnetic yoke assembly 40 to abut against a portion of the inner wall 27 of the storage portion in the length direction Y. However, the inner wall 27 of the storage portion may also have a portion other than the tapered portion 31 and the flat portion 32.

[0166] Figure 14 This is a variation of the torque sensor 10 according to the second embodiment, and is a schematic diagram showing that the inner wall 27 of the housing portion has an expanded diameter portion 36 and a reduced diameter portion 37. For example, as Figure 14 As shown, the inner wall 27 of the receiving portion 26 of the housing 20 may also have an enlarged diameter portion 36 and a reduced diameter portion 37 with different distances from each other to the outer peripheral surface 46 of the protrusion 45. In this case, the enlarged diameter portion 36 of the inner wall 27 of the receiving portion is located on the opening side of the receiving portion 26 in the insertion direction in which the protrusion 45 is inserted into the receiving portion 26, relative to the reduced diameter portion 37, and is formed separately from and parallel to the outer peripheral surface 46 of the protrusion 45. That is, the enlarged diameter portion 36 is disposed on the side where the sealing member abuts the portion 25 in the longitudinal direction Y relative to the reduced diameter portion 37.

[0167] Furthermore, the reduced diameter portion 37 of the inner wall 27 of the receiving portion is located further inward than the expanded diameter portion 36 in the insertion direction in which the protrusion 45 is inserted into the receiving portion 26, and the distance between it and the outer peripheral surface 46 of the protrusion 45 is smaller than the distance between the expanded diameter portion 36 and the outer peripheral surface 46 of the protrusion 45. That is, the reduced diameter portion 37 is disposed on the inner peripheral surface 21 of the housing 20 in the longitudinal direction Y relative to the expanded diameter portion 36 (see reference). Figure 11 On one side of the protrusion 45, the protrusion 36 is separated from the outer peripheral surface 46 of the protrusion 45 by a distance smaller than the distance between the diameter expansion portion 36 and the outer peripheral surface 46 of the protrusion 45, and is formed parallel to the outer peripheral surface 46.

[0168] As described above, a step portion 35 is formed between the enlarged diameter portion 36 and the reduced diameter portion 37, which are at different distances from each other to the outer peripheral surface 46 of the protrusion 45, and the enlarged diameter portion 36 and the reduced diameter portion 37 of the inner wall 27 of the receiving portion are connected by the step portion 35. The compression rib 47 abuts against the inner wall 27 of the receiving portion at the reduced diameter portion 37, relative to the inner wall 27 of the receiving portion having the enlarged diameter portion 36 and the reduced diameter portion 37. Therefore, the abutment length Lc of the compression rib 47 relative to the inner wall 27 of the receiving portion is the length in the longitudinal direction Y of the reduced diameter portion 37 of the inner wall 27 of the receiving portion. The reduced diameter portion 37 of the inner wall 27 of the receiving portion is a part in the longitudinal direction Y of the inner wall 27 of the receiving portion; therefore, the abutment length Lc of the compression rib 47 relative to the inner wall 27 of the receiving portion, which is the abutment length between the compression rib 47 and the reduced diameter portion 37, is shorter than the combined length Lp of the protrusion 45 and the inclined connecting portion 48 of the sensor housing 41.

[0169] The inner wall 27 of the receiving portion, having an enlarged diameter portion 36 and a reduced diameter portion 37, is formed, for example, by cutting the inner wall 27 of the receiving portion. That is, after the receiving portion 26 with a flat inner wall 27 is formed by casting, the enlarged diameter portion 36 is formed by cutting the portion of the inner wall 27 of the receiving portion near the sealing member abutment portion 25. Thus, an inner wall 27 of the receiving portion is formed having an enlarged diameter portion 36 and a reduced diameter portion 37 with different distances from each other to the protrusions 45 of the magnetic yoke assembly 40.

[0170] As described above, the inner wall 27 of the housing portion 26 of the housing 20 has an enlarged diameter portion 36 and a reduced diameter portion 37. The compression rib 47 disposed on the outer peripheral surface 46 of the protrusion 45 abuts against the inner wall 27 of the housing portion at the reduced diameter portion 37, so that the compression rib 47 can abut against the inner wall 27 of the housing portion at a position separated from the sealing member arrangement portion 44. Therefore, even if the protrusion 45 is deformed due to the abutment of the compression rib 47 against the inner wall 27 of the housing portion, the deformation of the protrusion 45 is unlikely to affect the sealing member arrangement portion 44, and the deformation of the sealing member arrangement portion 44 accompanying the deformation of the protrusion 45 can be suppressed more reliably. As a result, the flattening method of the O-ring 70 disposed in the sealing member arrangement portion 44 of the magnetic yoke assembly 40 can be uniformized. As a result, the sealing performance of the O-ring 70 can be improved.

[0171] Furthermore, by cutting the flat inner wall 27 of the receiving portion to form the enlarged diameter portion 36, the inner wall 27 of the receiving portion can be easily formed, having an enlarged diameter portion 36 and a reduced diameter portion 37 with different distances between them and the outer peripheral surface 46 of the protrusion 45 of the sensor housing 41 of the magnetic yoke assembly 40. Thus, it is easy to form an inner wall 27 of the receiving portion in which the contact length Lc between the compression rib 47 disposed on the outer peripheral surface 46 of the protrusion 45 and the inner wall 27 of the receiving portion is shorter than the length Lp of the protrusion 45. As a result, the sealing performance of the O-ring 70 can be easily improved.

[0172] Furthermore, in the first embodiment described above, the compression ribs 47 of the protrusion 45 of the magnetic yoke assembly 40 are disposed at six locations on the outer peripheral surface 46 of the protrusion 45, but the number of compression ribs 47 may also be other than this. The number of compression ribs 47 is not limited as long as they can properly position the protrusion 45 when it is housed in the housing portion 26 of the housing 20.

[0173] The preferred embodiments of this disclosure have been described above, but this disclosure is not limited to the contents described in the above embodiments. The structures described as embodiments and variations can also be appropriately combined.

[0174] Label Explanation

[0175] 10: Torque sensor; 20: Housing; 21: Inner circumferential surface; 25: Sealing component abutment part; 26: Reception part; 27: Inner wall of reception part; 31: Conical part; 32: Flat part; 35: Stepped part; 36: Expanded diameter part; 37: Reduced diameter part; 40: Magnetic yoke assembly; 41: Sensor housing; 42: Flange part; 43: Connector part; 44: Sealing component mounting part; 45: Protrusion part; 45a: End; 46: Outer circumferential surface; 47: Extrusion rib; 48: Inclined connection part; 50: Hall IC; 51: Lead frame ; 52: Circuit board; 55: Magnetic yoke; 60: Stator; 65: Magnet; 70: O-ring; 80: Steering device; 81: Steering wheel; 82: Steering shaft; 84: Universal joint; 85: Intermediate shaft; 86: Universal joint; 87: Short shaft; 87a: Torsion bar; 88: Steering gear; 88a: First pinion; 88b: Rack; 88c: Second pinion; 89: Tie rod; 100: ECU; 101: Vehicle speed sensor; 102: Electric motor; 103: Ignition switch; 104: Power supply unit.

Claims

1. A torque sensor, characterized in that, The torque sensor includes: Casing; and A magnetic yoke assembly is disposed inside the housing and is detachably mounted on the housing. The housing has a storage section for accommodating the magnetic yoke assembly. The magnetic yoke assembly includes a sealing component mounting section for mounting sealing components and a protrusion housed inside the mounting section. The protrusion has multiple compression ribs on its outer peripheral surface that abut against the inner wall of the storage portion, which serves as the inner wall of the storage portion. The protrusion has a height difference relative to the sealing member configuration by making its outline shape smaller when viewed in the insertion direction into the receiving part than the outline shape of the sealing member configuration part. An inclined connecting portion is provided between the sealing component mounting portion and the protrusion. The inclined connecting portion is inclined relative to the insertion direction and connects the sealing component mounting portion and the protrusion. The end of the compression rib on the side where the sealing member is located in the insertion direction is connected to the inclined connecting portion, and the compression rib abuts against the inner wall of the storage portion with a length shorter than the combined length of the protrusion and the inclined connecting portion in the insertion direction.

2. The torque sensor according to claim 1, wherein, Regarding the compression rib, its length in the insertion direction from the position of the sealing member configuration portion to the end on the opposite side of the side where the sealing member configuration portion is located is shorter than the combined length of the protrusion and the inclined connecting portion in the insertion direction.

3. The torque sensor according to claim 1, wherein, The torque sensor comprises: a magnet mounted on one of two shafts connected via a torsion bar; and a stator mounted on the other shaft. The compression ribs are disposed on the outer peripheral surfaces of the protrusion on both sides of the shaft in the axial direction.

4. The torque sensor according to claim 1, wherein, The torque sensor comprises: a magnet mounted on one of two shafts connected via a torsion bar; and a stator mounted on the other shaft. The compression ribs are disposed on the outer peripheral surfaces of the protrusion on both sides in a direction orthogonal to both the axial direction of the shaft and the insertion direction.

5. The torque sensor according to claim 1, wherein, The inner wall of the storage portion has: a tapered portion, which decreases the distance between the inner wall of the storage portion and the outer peripheral surface of the protrusion as it moves from the opening side of the storage portion toward the inner side in the insertion direction; and a flat portion, which is located further inward in the insertion direction than the tapered portion, so that the distance between the inner wall of the storage portion and the outer peripheral surface of the protrusion is constant. The compression rib abuts against the inner wall of the storage section at the flat portion.

6. The torque sensor according to claim 1, wherein, The inner wall of the receiving part has an enlarged diameter portion, which is located on the opening side of the receiving part in the insertion direction and is separated from the outer peripheral surface of the protrusion. And the reduced diameter portion, which is located further inward than the expanded diameter portion in the insertion direction, and the distance between it and the outer peripheral surface of the protrusion is smaller than the distance between the expanded diameter portion and the outer peripheral surface of the protrusion. The extrusion rib abuts against the inner wall of the receiving part at the narrowed diameter section.

7. The torque sensor according to claim 1, wherein, The housing has a sealing member abutment portion on the inlet side of the receiving portion in the insertion direction, for the sealing member to abut against the inner circumferential surface. The sealing member is disposed on the sealing member placement portion and abuts against both the sealing member placement portion and the sealing member contact portion at a position in the insertion direction closer to the inlet side than the receiving portion.

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