JP2014059179A - Torque detector and steering device with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a torque detector able to suppress thermal stress on a magnetism collection holder, and to provide a steering device that has the same.SOLUTION: A magnetism collection unit 50 for a torque detector comprises: a magnetism collection holder 70 formed by molding resin into an annular shape, and surrounding a magnetic yoke; a first magnetism collection ring 51 attached to the inner periphery 70X of the magnetism collection holder 70 and configured to collect the magnetic flux of the magnetic yoke; and a magnetic shield 60 formed by bending a metal plate and attached to the outer periphery 70Y of the magnetism collection holder 70. In the magnetism collection unit 50, a corner portion 61B of the first shield end 61 of the magnetic shield 60 is not in contact with the magnetism collection holder 70.

Description

  The present invention relates to a torque detection device having a magnetic flux collecting unit that collects magnetic flux from a magnetic yoke, a sensor housing formed integrally with the magnetic flux collecting unit, and a steering device including the same.

  A conventional torque detector includes a magnetism collecting unit in which a magnetism collecting ring and a magnetic shield are fixed to a ring holder, and a sensor housing. This torque detector has a configuration in which the magnetic flux collecting unit is fixed to the sensor housing in a state where the magnetic flux collecting unit is inserted into an insertion hole formed in the sensor housing. Patent Document 1 shows an example of a conventional torque detection device.

JP 2008-249598 A

  In the conventional torque detection device, water may enter the device from between the magnetism collecting unit and the housing. Therefore, in order to improve the waterproofness of the torque detection device, as shown in FIG. 10, torque detection for forming the sensor housing 220 integrally with the magnetism collecting unit 210 by pouring resin into the outer peripheral side of the magnetism collecting unit 210. A device 200 is conceivable.

  The magnetic flux collecting unit 210 includes a magnetic flux collecting holder 211, a magnetic flux collecting ring 212, and a magnetic shield 213. The magnetism collecting unit 210 has a configuration in which a magnetism collecting ring 212 is attached to the inner peripheral surface 211 </ b> X of the magnetism collecting holder 211 and a magnetic shield 213 is attached to the outer peripheral surface 211 </ b> Y of the magnetism collecting holder 211.

The magnetism collecting holder 211 is formed by resin molding. The magnetism collecting holder 211 has an annular shape.
The magnetic shield 213 is formed of a metal plate. The magnetic shield 213 has a C shape in plan view. The inner peripheral surface 213X of the magnetic shield 213 is in contact with the outer peripheral surface 211Y of the magnetism collecting holder 211. The shield end 213 </ b> A of the magnetic shield 213 is in contact with the end wall 211 </ b> A of the magnetism collecting holder 211.

  The sensor housing 220 is in close contact with the magnetism collecting holder 211 and the magnetic shield 213. The inner surface 221 of the sensor housing 220 is in contact with the outer peripheral surface 213Y of the magnetic shield 213.

  In the torque detection device 200, the linear expansion coefficient of the magnetism collecting holder 211 is larger than the linear expansion coefficient of the magnetic shield 213. For this reason, the amount of thermal expansion of the magnetism collecting holder 211 accompanying the temperature change of the torque detection device 200 is larger than the amount of thermal expansion of the magnetic shield 213, and the amount of thermal contraction of the magnetism collecting holder 211 is larger than the amount of thermal contraction of the magnetic shield 213. Many.

  For this reason, the corner portion 213B of the shield end 213A of the magnetic shield 213 is pressed against the end wall 211A of the magnetism collecting holder 211 as the temperature of the torque detection device 200 changes. Therefore, a large thermal stress is generated in the magnetism collecting holder 211 as the temperature of the torque detection device 200 changes.

  In order to solve the above-described problems, an object of the present invention is to provide a torque detection device capable of suppressing the occurrence of a large thermal stress in a magnetic flux collecting holder, and a steering device including the device.

  (1) The first means is: “a permanent magnet, a magnetic yoke that is disposed in a magnetic field formed by the permanent magnet and changes a relative position with the permanent magnet, and an annular shape formed by resin molding. A magnetic flux collecting holder that surrounds the magnetic yoke, a magnetic flux collecting ring that is attached to the inner circumferential surface of the magnetic flux collecting holder and collects the magnetic flux of the magnetic yoke, and is formed by bending a metal plate and is attached to the outer circumferential surface of the magnetic flux collecting holder An annular magnetic flux collecting unit in which at least one of corner portions of the shield end that is a circumferential end of the magnetic shield is in non-contact relation with the magnetic flux collecting holder, the permanent magnet, A magnetic sensor for detecting a magnetic flux of a magnetic circuit formed by the magnetic yoke and the magnetic flux collecting ring, and the magnetic flux collecting unit by a resin poured into an outer peripheral side of the magnetic flux collecting unit Having a torque detector "and a sensor housing which is integrally molded.

  In the torque detector, the magnetic flux collecting holder does not contact the corner portion of the shield end of the magnetic shield. For this reason, it is suppressed that the corner portion of the shield end is pressed against the magnetism collecting holder due to the temperature change of the torque detector due to the fact that the coefficient of linear expansion of the magnetism collecting holder is larger than the coefficient of linear expansion of the magnetic shield. Is done. Therefore, it is possible to suppress a large thermal stress from being generated in the magnetic flux collecting holder due to a temperature change of the torque detection device.

  (2) The second means is that “the magnetic flux collecting holders extend from the outer peripheral surface of the magnetic flux collecting holder toward the radially outward direction of the magnetic flux collecting holder and are separated from each other in the circumferential direction of the magnetic flux collecting holder. The shield end surface having two end walls, which is the end surface of the shield end portion in the circumferential direction of the magnetic shield, is opposed to the side surface of the end wall, and the magnetic flux collecting unit extends from the side surface of the end wall. The torque detecting device according to claim 1, further comprising a protrusion extending toward the shield end face.

  (3) The third means is that the torque detection according to claim 1 or 2, wherein the magnetism collecting holder has an end cover part that covers the shield end from the side opposite to the outer peripheral surface of the magnetism collecting holder. Device ".

  In the torque detection device, the end cover component prevents the corner portion of the shield end from coming into contact with the inner surface of the sensor housing. For this reason, it is suppressed that the corner | angular part of a shield edge part presses the inner surface of a sensor housing with the temperature change of a torque detection apparatus. Therefore, it is possible to suppress the occurrence of a large thermal stress on the inner surface of the sensor housing due to the temperature change of the torque detection device.

  (4) The fourth means is that "the end cover component has a protrusion extending toward the shield end, and the protrusion contacts the shield end." Is included.

  In the torque detection device, the position of the shield end with respect to the magnetic flux collecting holder is determined by the protrusion. For this reason, the projection of the end cover part is omitted, and the shield end relative to the magnetism collecting ring is compared with the configuration in which the shield end is assumed to be inserted between the end cover part and the outer peripheral surface of the magnetism collecting holder. The position of the part can be determined accurately. Also, compared to the configuration in which the projection is omitted from the end cover part and the shield end is pressed into the outer peripheral surface of the end cover part and the magnetic flux collection holder, the shield end is easier to attach to the magnetic flux collection holder. Become.

  (5) The fifth means is as described in any one of claims 1 to 4, wherein the magnetism collecting holder has a body cover part that covers a part of a shield body that connects the shield end portions from the outside. Torque detection device ".

  In the torque detector, the position of the shield body relative to the magnetism collecting holder is determined by the body cover component. For this reason, a shield main body is hold | maintained by the magnetism collection holder in an appropriate shape.

  (6) The sixth means includes the "torque detection device according to claim 5, wherein the main body cover part has a protrusion extending toward the shield main body, and the protrusion contacts the shield main body". .

  In the torque detection device, the position of the shield body with respect to the magnetic flux collecting holder is determined by the protrusion. For this reason, the protrusion of the main body cover part is omitted, and the position of the shield main body with respect to the magnetic flux collecting ring is compared with the configuration in which the shield main body is assumed to be inserted between the main body cover part and the outer peripheral surface of the magnetic flux collecting holder. Can be determined accurately. In addition, it is easier to attach the shield body to the magnetic flux collecting holder than in the configuration in which the protrusion is omitted from the main body cover component and the shield main body is pressed into the outer peripheral surface of the main body cover component and the magnetic flux collecting holder.

  (7) The seventh means includes the “steering device having the torque detection device according to any one of claims 1 to 6”.

  The torque detection device and the steering device including the same device can suppress the occurrence of large thermal stress in the magnetic flux collecting holder.

The block diagram which shows the structure of the steering device of embodiment. The perspective view which shows the disassembled perspective structure of the torque detection apparatus of embodiment. Sectional drawing which shows the cross-section of the torque detection apparatus of embodiment. The perspective view which shows the disassembled perspective structure of the magnetic flux collecting unit of embodiment. The perspective view which shows the perspective structure of the magnetic flux collecting unit of embodiment. It is a figure which shows the magnetic flux collecting unit of embodiment, (a) is sectional drawing which shows the cross-section of a magnetic collecting unit, (b) is sectional drawing which shows the cross-sectional structure of Z6-Z6 plane of (a). It is sectional drawing which shows the sensor unit of embodiment, (a) is sectional drawing which shows each shield edge part of a magnetic shield, and its surrounding sectional structure, (b) shows the enlarged structure of the dashed-dotted line circle of (a). Enlarged view. FIG. 3 is a development view showing a positional relationship between a permanent magnet, each magnetic yoke, and each magnetism collecting ring in the torque detection device of the embodiment. The side view which shows a part of side structure of the magnetic flux collecting unit of other embodiment. Sectional drawing which shows the cross-section of a part of the torque detection apparatus of a comparative example.

The configuration of the steering device 1 will be described with reference to FIG.
The steering device 1 includes a steering device body 10, an assist device 20, and a torque detection device 30. The steering device 1 has a configuration as a dual pinion assist type electric power steering device in which the assist device 20 assists the operation of the steering wheel 2.

  The steering device body 10 includes a column shaft 11, an intermediate shaft 12, a pinion shaft 13, a rack shaft 14, a rack and pinion mechanism 15, two tie rods 16, and a rack housing 17. The steering device body 10 integrally rotates the column shaft 11, the intermediate shaft 12, and the pinion shaft 13 as the steering wheel 2 rotates. The steering device body 10 causes the rack shaft 14 to move straight in the longitudinal direction by the rotation of the pinion shaft 13. The steering device body 10 changes the turning angle of the steered wheels 3 by causing the rack shaft 14 to advance straight.

  The pinion shaft 13 includes a first shaft 13A, a second shaft 13B, and a torsion bar 13D. The pinion shaft 13 has a configuration in which a torsion bar 13D connects the first shaft 13A and the second shaft 13B.

The first shaft 13 </ b> A is connected to the intermediate shaft 12. The first shaft 13 </ b> A rotates integrally with the intermediate shaft 12.
The second shaft 13B has a pinion gear 13C. In the second shaft 13B, the pinion gear 13C meshes with the first rack gear 14A of the rack shaft 14.

  The rack shaft 14 has a first rack gear 14A and a second rack gear 14B. The first rack gear 14 </ b> A has a plurality of rack teeth formed over a predetermined range in the longitudinal direction of the rack shaft 14. The second rack gear 14B is formed in a portion of the rack shaft 14 that is separated from the first rack gear 14A. The second rack gear 14 </ b> B has a plurality of rack teeth formed over a predetermined range in the longitudinal direction of the rack shaft 14.

  The rack and pinion mechanism 15 includes a pinion gear 13 </ b> C of the pinion shaft 13 and a first rack gear 14 </ b> A of the rack shaft 14. The rack and pinion mechanism 15 converts the rotation of the pinion shaft 13 into straight travel of the rack shaft 14.

  The rack housing 17 is formed of a metal material. The rack housing 17 has a cylindrical shape corresponding to the shape of the rack shaft 14. The rack housing 17 accommodates a part of the pinion shaft 13, the rack shaft 14, and the tie rod 16 in the internal space.

  The assist device 20 includes an assist motor 21, a worm shaft 22, a worm wheel 23, and a pinion shaft 24. In the assist device 20, the output shaft of the assist motor 21 is connected to the worm shaft 22. In the assist device 20, the worm shaft 22 and the worm wheel 23 are engaged with each other. In the assist device 20, the worm wheel 23 rotates integrally with the pinion shaft 24. In the assist device 20, the pinion gear 24A of the pinion shaft 24 meshes with the second rack gear 14B. The assist device 20 acts in the longitudinal direction of the rack shaft 14 by transmitting the rotation of the assist motor 21 to the pinion shaft 24 in a state where the rotation of the assist motor 21 is decelerated through the worm shaft 22 and the worm wheel 23 and rotating the pinion shaft 24. To the rack shaft 14.

  The torque detection device 30 is located around the pinion shaft 13. The torque detection device 30 is fixed to the fixed component 17 </ b> A of the rack housing 17. The torque detection device 30 detects the torque applied to the pinion shaft 13.

With reference to FIG. 2 and FIG. 3, the structure of the torque detection apparatus 30 is demonstrated. In FIG. 2, the sensor unit 40 in which the circuit unit 90 is omitted is shown.
Here, as the respective directions related to the torque detection device 30, “axial direction ZA”, “upward direction ZA1”, “downward direction ZA2”, “radial direction ZB”, “inward direction ZB1”, “outward direction ZB2”, and “ "Circumferential direction ZC" is defined.

The circumferential direction ZC indicates a direction around the rotation center axis of the pinion shaft 13 (see FIG. 3).
The axial direction ZA indicates a direction along the rotation center axis of the pinion shaft 13. The axial direction ZA is defined by an upward direction ZA1 and a downward direction ZA2 indicating directions opposite to each other. An upward direction ZA1 indicates a direction in which the second shaft 13B and the first shaft 13A (both refer to FIG. 3) pass in order. The downward direction ZA2 indicates a direction passing through the first shaft 13A and the second shaft 13B in this order.

  The radial direction ZB indicates a normal direction of the axial direction ZA. The radial direction ZB is defined by an inner direction ZB1 and an outer direction ZB2 indicating directions opposite to each other. The inward direction ZB1 indicates a direction approaching the rotation center axis of the pinion shaft 13. The outward direction ZB2 indicates a direction away from the rotation center axis of the pinion shaft 13.

  As shown in FIG. 2, the torque detection device 30 includes a sensor unit 40, a magnet unit 100, and a magnetic yoke unit 110. The torque detection device 30 has a configuration in which the magnet unit 100 and the magnetic yoke unit 110 are accommodated in the internal space 85 of the sensor unit 40.

  As shown in FIG. 3, in the torque detection device 30, a gap between the torque detection device 30 and the first shaft 13 </ b> A is sealed with an oil seal 31. In the torque detection device 30, a gap between the torque detection device 30 and the fixed component 17 </ b> A of the rack housing 17 is sealed by an O-ring 32.

  The magnet unit 100 is fixed to the first shaft 13A. The magnet unit 100 includes a permanent magnet 101 and a core 102. The magnet unit 100 is configured as an assembly in which a permanent magnet 101 and a core 102 are coupled to each other.

  The permanent magnet 101 has a cylindrical shape. The permanent magnet 101 has an N pole and an S pole adjacent to each other in the circumferential direction ZC (see FIG. 2). The permanent magnet 101 forms a magnetic field around the first shaft 13A.

  The core 102 is fixed to the inner peripheral surface of the permanent magnet 101. The core 102 is press-fitted into the outer peripheral surface of the first shaft 13A. The core 102 suppresses leakage of the magnetic flux of the permanent magnet 101 in the inward direction ZB1 from the core 102.

  The magnetic yoke unit 110 surrounds the magnet unit 100. The magnetic yoke unit 110 is fixed to the second shaft 13B. The magnetic yoke unit 110 includes a first magnetic yoke 111, a second magnetic yoke 112, a yoke holder 113, and an intermediate part 114.

  The yoke holder 113 is resin-molded integrally with the first magnetic yoke 111 and the second magnetic yoke 112. The yoke holder 113 has an annular shape. The yoke holder 113 is fixed to the second shaft 13B via the intermediate part 114.

  The first magnetic yoke 111 has an annular shape. The first magnetic yoke 111 is positioned in the upward direction ZA1 of the yoke holder 113. The first magnetic yoke 111 has a plurality of tooth portions 111A and a plurality of connection portions 111B (see FIG. 8). The first magnetic yoke 111 has a tapered shape in which the tooth portion 111A tapers as it goes in the downward direction ZA2 (see FIG. 8). The first magnetic yoke 111 has a configuration in which tooth portions 111A adjacent in the circumferential direction ZC are connected to each other by a connecting portion 111B (see FIG. 8). The first magnetic yoke 111 receives the magnetic flux of the permanent magnet 101. The first magnetic yoke 111 changes its position relative to the permanent magnet 101 as the torsion bar 13D is twisted.

  The second magnetic yoke 112 has an annular shape. The second magnetic yoke 112 is located in the downward direction ZA2 of the yoke holder 113. The second magnetic yoke 112 has a plurality of teeth 112A and a plurality of connection portions 112B (see FIG. 8). The second magnetic yoke 112 has a tapered shape in which the tooth portion 112A tapers as it goes in the upward direction ZA1 (see FIG. 8). The second magnetic yoke 112 has a configuration in which teeth 112A adjacent in the circumferential direction ZC are connected to each other by a connecting portion 112B (see FIG. 8). In the second magnetic yoke 112, the tooth portion 112A is located between the tooth portions 111A adjacent in the circumferential direction ZC. The second magnetic yoke 112 receives the magnetic flux of the permanent magnet 101. The relative position of the second magnetic yoke 112 with the permanent magnet 101 changes as the torsion bar 13D is twisted.

  The sensor unit 40 is fixed to the fixing component 17A of the rack housing 17 by a first bolt (not shown). The sensor unit 40 includes a Hall IC as two magnetic sensors 41, a magnetism collecting unit 50, a sensor housing 80, and a circuit unit 90.

  The magnetic flux collecting unit 50 has an annular shape surrounding the magnet unit 100 and the magnetic yoke unit 110. The magnetic flux collecting unit 50 includes a first magnetic flux collecting ring 51, a second magnetic flux collecting ring 54, a magnetic shield 60, and a magnetic flux collecting holder 70. The magnetic flux collecting unit 50 is configured as an aggregate in which the magnetic flux collecting rings 51 and 54 and the magnetic shield 60 are attached to the magnetic flux collecting holder 70. The magnetic flux collecting unit 50 collects the magnetic flux of the magnetic yoke unit 110 and causes the magnetic flux to flow toward the magnetic sensor 41.

  The two magnetic sensors 41 are adjacent to each other in the circumferential direction ZC. The magnetic sensor 41 detects the magnetic flux of the magnetic circuit formed by the permanent magnet 101, the magnetic yokes 111 and 112, and the magnetic flux collecting rings 51 and 54. The magnetic sensor 41 outputs a voltage corresponding to the magnetic flux density of the magnetic circuit. The output voltage of the magnetic sensor 41 is transmitted to the control device (not shown) of the steering device 1 (see FIG. 1) via the circuit unit 90.

  The sensor housing 80 is resin-molded integrally with the magnetism collecting unit 50 as shown in FIG. The sensor housing 80 includes a housing main body 81, a substrate support portion 82, a substrate attachment portion 83, a device attachment portion 84, and an internal space 85. The sensor housing 80 has a configuration in which a housing main body 81, a substrate support portion 82, a substrate attachment portion 83, and a device attachment portion 84 are integrally formed of the same resin material.

  The housing body 81 is formed in a cylindrical shape having an internal space 85 penetrating in the axial direction ZA. The housing body 81 has a base portion 81A and a magnetism collecting portion 81B. In the housing main body 81, the magnetism collecting portion 81B is positioned in the upward direction ZA1 of the base portion 81A.

  The board attachment portions 83 are located on both sides of the board support portion 82 in a plan view of the sensor housing 80. The board attachment portion 83 has an insertion hole into which a second bolt (not shown) is inserted. In the board attachment portion 83, the circuit unit 90 (see FIG. 3) is attached.

  The device attachment portions 84 are located at both end portions in the longitudinal direction of the base portion 81 </ b> A of the housing body 81 in the plan view of the sensor housing 80. The device attachment portion 84 has a through hole into which the first bolt is inserted.

  The substrate support portion 82 has a cylindrical shape. The substrate support portion 82 is formed in the magnetic flux collection portion 81B of the housing body 81. The substrate support portion 82 protrudes from the housing body 81 in the outward direction ZB2. The board support portion 82 supports the circuit board 91 (see FIG. 3) of the circuit unit 90.

A detailed configuration of the magnetic flux collecting unit 50 will be described with reference to FIG.
The magnetic flux collecting unit 50 includes a first magnetic flux collecting ring 51, a second magnetic flux collecting ring 54, a magnetic shield 60, and a magnetic flux collecting holder 70. The magnetic flux collecting unit 50 has a configuration in which the magnetic flux collecting rings 51 and 54 and the magnetic shield 60 are attached to the magnetic flux collecting holder 70.

  The first magnetism collecting ring 51 is formed by bending a long metal plate. The first magnetism collecting ring 51 faces the outer peripheral portion of the first magnetic yoke 111 (see FIG. 3) via a gap in the radial direction ZB. The first magnetism collecting ring 51 has a ring main body 52 and two magnetism collecting projections 53. The first magnetism collecting ring 51 has a configuration in which a ring body 52 and two magnetism collecting projections 53 are integrally formed. The first magnetism collecting ring 51 collects the magnetic flux of the first magnetic yoke 111.

  The ring body 52 has an annular shape with a gap. The ring body 52 has a spacing portion 52A. The ring body 52 has a configuration in which the separation portion 52A is formed as a discontinuous portion of the ring body 52 in the circumferential direction ZC.

  The magnetic flux collecting protrusions 53 are adjacent to each other in the circumferential direction ZC. The magnetic flux collecting protrusion 53 has a shape bent from the lower end portion of the ring main body 52 toward the outward direction ZB2. The magnetic flux collecting projection 53 faces the upper surface of the magnetic sensor 41 (see FIG. 3) in the axial direction ZA.

  The second magnetism collecting ring 54 is formed by bending the same long metal plate as the first magnetism collecting ring 51. The second magnetism collecting ring 54 faces the outer peripheral portion of the second magnetic yoke 112 (see FIG. 3) via a gap in the radial direction ZB. The second magnetism collecting ring 54 has a ring main body 55 and two magnetism collecting projections 56. The second magnetism collecting ring 54 has a configuration in which a ring main body 55 and two magnetism collecting projections 56 are integrally formed. The second magnetism collecting ring 54 collects the magnetic flux of the second magnetic yoke 112.

  The ring body 55 has an annular shape with a gap. The ring body 55 has a separation portion 55A. The ring body 55 has a configuration in which the separation portion 55A is formed as a discontinuous portion of the ring body 55 in the circumferential direction ZC.

  The magnetic flux collecting projections 56 are adjacent in the circumferential direction ZC. The magnetic flux collecting projection 56 has a shape bent from the upper end portion of the ring main body 55 toward the outward direction ZB2. The magnetic flux collecting projection 56 faces the lower surface of the magnetic sensor 41 in the axial direction ZA.

  The magnetic shield 60 is formed by bending a single metal long plate serving as a magnetic body. The magnetic shield 60 has a first shield end 61, a second shield end 62, a shield body 63, and a separation portion 64. The magnetic shield 60 has a configuration formed in a C shape. The magnetic shield 60 has a configuration in which the first shield end 61 forms one end of the long plate and the second shield end 62 forms the other end of the long plate. The magnetic shield 60 has a separation portion 64 as a portion between the first shield end portion 61 and the second shield end portion 62 that are adjacent to each other in the circumferential direction ZC. The magnetic shield 60 has a configuration in which a first shield end 61 and a second shield end 62 are connected by a shield body 63. The magnetic shield 60 is connected to a magnetic circuit formed by the magnetic flux collecting rings 51 and 54, the magnetic yokes 111 and 112, and the permanent magnet 101 (both see FIG. 3) by the external magnetic field of the torque detector 30 (see FIG. 3). To reduce the impact.

  The magnetism collecting holder 70 is formed of the same resin material as that of the sensor housing 80. The magnetism collecting holder 70 has an annular shape that is open on both sides in the axial direction ZA. The magnetic flux collecting holder 70 has an internal space for accommodating the magnet unit 100 and the magnetic yoke unit 110 (both see FIG. 3). The magnetic flux collecting holder 70 includes a holding convex portion 71, an upper through hole 74, a lower through hole 75, an insertion portion 76, a shield holding portion 77, three main body cover parts 78, and two end cover parts 79. . The magnetic flux collecting holder 70 holds the magnetic flux collecting rings 51 and 54 and the magnetic shield 60.

  The holding protrusion 71 protrudes from the inner peripheral surface 70X of the magnetism collecting holder 70 toward the inner direction ZB1. The holding convex portion 71 has a plurality of first holding portions 72 and a plurality of second holding portions 73. The holding convex portion 71 has a function of holding the magnetic flux collecting rings 51 and 54 by the first holding portion 72 and the second holding portion 73.

  The first holding portion 72 is positioned on both sides of the second holding portion 73 in the axial direction ZA on the inner peripheral surface 70 </ b> X of the magnetism collecting holder 70. The 1st holding | maintenance part 72 is spaced apart and formed in the circumferential direction ZC.

  The second holding portion 73 is formed in an arc shape in plan view of the magnetism collecting holder 70. The second holding portion 73 is located at the center portion in the axial direction ZA on the inner peripheral surface 70 </ b> X of the magnetism collecting holder 70. The second holding portion 73 is formed to be separated in the circumferential direction ZC.

  The upper through hole 74 penetrates the magnetic flux collecting holder 70 in the radial direction ZB. The upper through hole 74 is located in a portion between the upper first holding portion 72 and the second holding portion 73 in the magnetic flux collecting holder 70. The upper through-hole 74 is formed because a slide core (not shown) that forms the first holding portion 72 is located in a mold for forming the magnetic flux collecting holder 70.

  The lower through hole 75 penetrates the magnetic flux collecting holder 70 in the radial direction ZB. The lower through-hole 75 is located in a portion between the lower first holding portion 72 and the second holding portion 73 in the magnetism collecting holder 70. The lower through-hole 75 is formed because a slide core (not shown) that forms the second holding portion 73 is located in a mold for forming the magnetic flux collecting holder 70.

  The insertion portion 76 is formed as a rectangular opening portion in which the circumferential direction ZC is a longitudinal direction and the axial direction ZA is a short direction in a side view of the magnetic flux collecting holder 70. The insertion portion 76 has an insertion hole 76A, an upper projection 76B, and a lower projection 76C.

The upper protrusion 76 </ b> B serves as a mark for determining the position in the circumferential direction ZC of the first magnetic flux collecting ring 51 with respect to the magnetic flux collecting holder 70.
The lower protrusion 76C serves as a mark for determining the position in the circumferential direction ZC of the second magnetism collecting ring 54 with respect to the magnetism collecting holder 70.

  The shield holding portion 77 is formed as a wall portion protruding in the outward direction ZB2 from the outer peripheral surface 70Y of the magnetism collecting holder 70. The shield holding portion 77 has an upper wall 77A, a lower wall 77B, and an end wall 77C. The shield holding portion 77 restricts the movement of the magnetic shield 60 relative to the magnetism collecting holder 70.

The upper wall 77A is located at the upper end portion of the magnetism collecting holder 70. The upper wall 77A restricts the movement of the magnetic shield 60 in the upward direction ZA1.
The lower wall 77B is located at the lower end portion of the magnetism collecting holder 70. The lower wall 77B restricts the movement of the magnetic shield 60 in the downward direction ZA2.

  The end walls 77C are formed at positions adjacent to both end portions in the circumferential direction ZC of the insertion portion 76 in the magnetic flux collecting holder 70 in the circumferential direction ZC. The end wall 77C restricts the movement of the magnetic shield 60 in the circumferential direction ZC. The end wall 77C has a protrusion 77E that protrudes in the circumferential direction ZC from the side surface 77D opposite to the insertion portion 76 in the circumferential direction ZC. The protrusion 77E extends from the lower end surface of the upper wall 77A of the magnetism collecting holder 70 to the upper end surface of the lower wall 77B.

  The main body cover part 78 is formed integrally with the magnetism collecting holder 70. The main body cover part 78 has an arc shape in plan view. The main body cover part 78 extends in the downward direction ZA2 from the outer peripheral surface of the upper wall 77A of the magnetism collecting holder 70. The main body cover part 78 is positioned with respect to the outer peripheral surface 70Y of the magnetism collecting holder 70 via a gap.

  The end cover part 79 is formed of the same material as the resin material of the sensor housing 80. The end cover part 79 has an arc shape in plan view. The end cover component 79 is fixed to the magnetic flux collecting holder 70 by welding or the like in contact with the outer circumferential surface of the end wall 77C of the magnetic flux collecting holder 70, the outer circumferential surface of the upper wall 77A, and the outer circumferential surface of the lower wall 77B. The end cover part 79 has a protrusion 79A. The end cover part 79 is positioned with respect to the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70 via a gap.

With reference to FIG. 5, a configuration in which the magnetic flux collecting rings 51 and 54 and the magnetic shield 60 are attached to the magnetic flux collecting holder 70 will be described.
The first magnetism collecting ring 51 is sandwiched between the upper first holding portion 72 and the second holding portion 73 in the magnetism collecting holder 70. The first magnetism collecting ring 51 covers the upper through hole 74 from the inner direction ZB1 of the magnetism collecting holder 70. In the first magnetic flux collecting ring 51, the magnetic flux collecting projection 53 protrudes in the outward direction ZB 2 from the magnetic flux collecting holder 70 through the insertion portion 76.

  The second magnetism collecting ring 54 is sandwiched between the lower first holding portion 72 and the second holding portion 73 in the magnetism collecting holder 70. The second magnetism collecting ring 54 covers the lower through hole 75 from the inner direction ZB1 of the magnetism collecting holder 70. In the second magnetic flux collecting ring 54, the magnetic flux collecting projection 56 protrudes in the outward direction ZB 2 from the magnetic flux collecting holder 70 through the insertion portion 76.

  The magnetic shield 60 has an inner peripheral surface 60 </ b> X (see FIG. 4) that contacts an outer peripheral surface 70 </ b> Y (see FIG. 4) of the magnetism collecting holder 70. The magnetic shield 60 covers the upper through hole 74 and the lower through hole 75 from the outward direction ZB2 of the magnetism collecting holder 70. In the magnetic shield 60, the shield body 63 is sandwiched between the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70 and the body cover component 78. In the magnetic shield 60, the shield end portions 61 and 62 (see FIG. 4) are sandwiched between the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70 and the end cover component 79.

A detailed configuration of the main body cover part 78 of the magnetic flux collecting holder 70 will be described with reference to FIG.
As shown in FIG. 6A, the three main body cover parts 78 are spaced apart from each other in the circumferential direction ZC. The distances in the circumferential direction ZC between adjacent main body cover parts 78 are equal to each other.

  As shown in FIG. 6B, the main body cover part 78 has a protrusion 78A. In the body cover component 78, the protrusion 78 </ b> A contacts the outer peripheral surface 60 </ b> Y of the magnetic shield 60 in a state where the magnetic shield 60 is attached to the magnetism collecting holder 70. The main body cover part 78 is covered from the outer direction ZB2 by the sensor housing 80. The outer peripheral surface of the main body cover part 78 is in contact with the inner surface 81 </ b> C of the sensor housing 80.

  The protrusion 78A has a semicircular shape in a side view in the circumferential direction ZC. The protrusion 78 </ b> A protrudes from the inner peripheral surface of the main body cover part 78 toward the shield main body 63. The protrusion 78 </ b> A is located at the lower end portion of the main body cover part 78. The dimension in the circumferential direction ZC of the protrusion 78A is equal to the dimension in the circumferential direction ZC of the main body cover part 78 (see FIG. 6A).

  With reference to FIG. 7, the detailed configuration of the end wall 77C and the end cover part 79 of the magnetism collecting holder 70 will be described. As shown in FIG. 7A, the configuration of the end cover part 79 that covers the second shield end 62 of the magnetic shield 60 is the same as the configuration of the end cover part 79 that covers the first shield end 61. Since it is the same, the description is abbreviate | omitted. The configuration of the end wall 77C facing the second shield end portion 62 is the same as that of the end wall 77C facing the first shield end portion 61, and the description thereof is omitted.

  As shown in FIG. 7B, the protrusion 77 </ b> E of the end wall 77 </ b> C contacts the central portion in the radial direction ZB of the shield end surface 61 </ b> A of the first shield end portion 61. That is, the protrusion 77E does not contact the corner portion 61B of the shield end surface 61A. For this reason, 61 A of shield end surfaces are located in the side surface 77D of the end wall 77C, and the circumferential direction ZC through space. For this reason, the corner portion 61B of the shield end surface 61A does not contact the side surface 77D of the end wall 77C. The corner portion 61B is configured as a connecting portion between the inner peripheral surface 60X of the magnetic shield 60 and the shield end surface 61A and a connecting portion between the outer peripheral surface 60Y of the magnetic shield 60 and the shield end surface 61A.

  The projection 79A of the end cover part 79 has a semicircular shape in plan view. The protrusion 79 </ b> A protrudes from the inner peripheral surface of the end cover part 79 toward the first shield end 61. The protrusion 79 </ b> A contacts a portion corresponding to the first shield end 61 on the outer peripheral surface 60 </ b> Y of the magnetic shield 60. The protrusion 79A is located at the end of the end cover component 79 opposite to the end wall 77C in the circumferential direction ZC. The protrusion 79A is formed from the upper wall 77A to the lower wall 77B (both see FIG. 4) in the axial direction ZA. The protrusion 79A is in contact with the lower end surface of the upper wall 77A at the upper end surface. The protrusion 79A is in contact with the upper end surface of the lower wall 77B at the lower end surface.

  The magnetic flux collecting holder 70 is formed with a closed space S surrounded by the end cover part 79, the end wall 77C, the outer peripheral surface 70Y of the magnetic flux collecting holder 70, and the first shield end portion 61. In the closed space S, the resin material of the sensor housing 80 is suppressed from flowing when the sensor housing 80 is molded.

  An inner surface 81 </ b> C of the sensor housing 80 contacts the outer peripheral surface 60 </ b> Y of the magnetic shield 60 and the outer surface of the main body cover component 78. For this reason, the inner surface 81 </ b> C of the sensor housing 80 does not contact the corner portion 61 </ b> B of the first shield end portion 61.

A method for manufacturing the sensor unit 40 will be described.
The manufacturing method of the sensor unit 40 includes a magnetic flux collecting unit assembly process and a housing molding process.

The magnetism collecting unit assembling process includes a magnetism collecting ring assembling process and a magnetic shield assembling process.
In the magnetism collecting ring assembling step, the operator sandwiches the first magnetism collecting ring 51 between the first holding part 72 and the second holding part 73 on the upper side of the magnetism collecting holder 70. The operator sandwiches the second magnetism collecting ring 54 between the first holding portion 72 and the second holding portion 73 on the lower side of the magnetism collecting holder 70.

  In the magnetic shield assembling step, the operator elastically deforms the magnetic shield 60 so that the distance between the shield end portions 61 and 62 of the magnetic shield 60 is increased. In this state, the operator inserts the magnetic shield 60 into the magnetic flux collecting holder 70 from the upward direction ZA1 of the magnetic flux collecting holder 70. At this time, the operator inserts the shield main body 63 of the magnetic shield 60 between the main body cover part 78 of the magnetic flux collecting holder 70 and the outer peripheral surface 70Y. Then, the operator inserts the shield end portions 61 and 62 of the magnetic shield 60 between the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70 and the end cover component 79. At this time, the shield end portions 61 and 62 are in contact with the protrusions 77E of the end wall 77C of the magnetism collecting holder 70.

  In the housing molding process, the operator sets the magnetic flux collecting unit 50 manufactured in the magnetic flux collecting unit assembling process in a mold for molding the sensor housing 80. Then, the operator pours the resin material of the sensor housing 80 into the outer peripheral side of the magnetism collecting unit 50 using a mold. Thereby, the sensor housing 80 is formed integrally with the magnetism collecting unit 50.

The operation of the torque detection device 30 will be described with reference to FIGS.
The torque detection device 30 has first to third functions. The first function is a function of suppressing a large thermal stress from being generated in the magnetic flux collecting holder 70. The second function has a function of suppressing the occurrence of large thermal stress on the inner surface 81C of the sensor housing 80. The third function is a function that makes the position of the magnetic shield 60 relative to the magnetism collecting holder 70 accurate.

Details of the first function will be described.
Since the linear expansion coefficient of the magnetic flux collecting holder 70 is larger than the linear expansion coefficient of the magnetic shield 60, the thermal expansion amount in the circumferential direction ZC of the magnetic flux collecting holder 70 is larger than the thermal expansion amount in the circumferential direction ZC of the magnetic shield 60. Further, the amount of heat shrinkage in the circumferential direction ZC of the magnetic flux collecting holder 70 is larger than the amount of heat shrinkage in the circumferential direction ZC of the magnetic shield 60.

  On the other hand, as shown in FIG. 7B, in the torque detection device 30, the corner portion 61 </ b> B of the first shield end 61 of the magnetic shield 60 is in contact with the protrusion 77 </ b> E of the end wall 77 </ b> C of the magnetism collecting holder 70. . For this reason, the corner | angular part 61B of the 1st shield end part 61 does not contact the side surface 77D of the end wall 77C. For this reason, it is suppressed that the corner | angular part 61B of the 1st shield end part 61 is pressed on side surface 77D of the end wall 77C with the temperature change of the torque detection apparatus 30. FIG. Therefore, compared with the torque detection apparatus 200 (refer FIG. 10), it is suppressed that a big thermal stress arises in the magnetism collection holder 70. FIG. In addition, since the effect | action of the end shield 77C facing the 2nd shield end part 62 and the same shield end part 62 is the same as the said effect | action, the description is abbreviate | omitted.

Details of the second function will be described.
As shown in FIG. 7B, in the magnetic flux collecting unit 50, the end cover part 79 covers the first shield end 61 from the outer direction ZB2. For this reason, the inner surface 81 </ b> C of the sensor housing 80 does not contact the first shield end portion 61. For this reason, the corner portion 61 </ b> B of the first shield end 61 is suppressed from being pressed against the inner surface 81 </ b> C of the sensor housing 80 as the temperature of the torque detection device 30 changes. Therefore, compared to the torque detection device 200, it is possible to suppress a large thermal stress from being generated on the inner surface 81C of the sensor housing 80. The operation of the second shield end portion 62 and the end cover part 79 that covers the shield end portion 62 is the same as the above-described operation, and thus the description thereof is omitted.

Details of the third function will be described.
As shown in FIG. 10, in the torque detection device 200, when an operator elastically deforms the magnetic shield 213 to attach it to the magnetism collecting holder 211, the magnetic shield 213 is mistakenly plastically deformed by force. There is a case. At this time, the magnetic shield 213 is partially separated from the outer circumferential surface 211 </ b> Y of the magnetism collecting holder 211 in the circumferential direction ZC. When the resin material of the sensor housing 220 is poured around the magnetic flux collecting unit 210, the resin material flows between the magnetic shield 213 and the outer peripheral surface 211 </ b> Y of the magnetic flux collecting holder 211. As a result, the magnetic shield 213 is further separated from the outer peripheral surface 211 </ b> Y of the magnetism collecting holder 211. For this reason, the magnetic shield 213 may be exposed to the outside of the sensor housing 220.

  As described above, in the torque detection device 200, the magnetic shield 213 is separated from the outer peripheral surface 211 </ b> Y of the magnetic flux collecting holder 211, so that the magnetic shield 213 is separated from the magnetic flux collecting ring 212. For this reason, the function by which the magnetic shield 213 reduces the influence from the external magnetic field of the magnetism collection ring 212 falls. Further, since the magnetic shield 213 is exposed to the outside of the sensor housing 220, the sensor housing 220 is not configured to be continuous in the circumferential direction ZC. That is, the portion of the sensor housing 220 that houses the magnetic shield 213 is divided by the magnetic shield 213 in the circumferential direction ZC. For this reason, the strength of the sensor housing 220 is reduced.

  On the other hand, as shown in FIG. 6, in the magnetic flux collecting unit 50 of the present embodiment, the magnetic shield 60 is sandwiched between the outer peripheral surface 70 </ b> Y of the magnetic flux collecting holder 70 by the cover parts 78 and 79. Therefore, even if the operator plastically deforms the magnetic shield 60, the cover parts 78 and 79 press the magnetic shield 60 toward the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70. For this reason, it is suppressed that the magnetic shield 60 separates from the outer peripheral surface 70Y of the magnetism collecting holder 70. Thereby, each shield end part 61 and 62 and the shield main body 63 are hold | maintained at the magnetism collection holder 70 by a suitable shape. For this reason, the resin material of the sensor housing 80 (see FIG. 7) is prevented from flowing between the magnetic shield 60 and the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70. Therefore, it is possible to suppress a decrease in the function of reducing the influence of the magnetic flux collecting rings 51 and 54 from the external magnetic field due to the magnetic shield 60 and a decrease in the strength of the sensor housing 80.

With reference to FIG. 8, the detection of the magnetic flux density of the torque detector 30 will be described.
FIG. 8A shows a state where torque is not applied between the first shaft 13A and the second shaft 13B (both see FIG. 1) (hereinafter, “neutral state”). FIG. 8B shows a state in which a clockwise torque is applied between the first shaft 13A and the second shaft 13B (hereinafter, “right-rotation state”). FIG. 8C shows a state in which a counterclockwise torque is applied between the first shaft 13A and the second shaft 13B (hereinafter, referred to as “counterclockwise rotation state”).

  As the relationship between the magnetic yokes 111 and 112 and the permanent magnet 101, “first N pole facing area”, “first S pole facing area”, “second N pole facing area”, and “second S pole facing area” are defined. .

  The first N-pole facing area indicates the facing area between the first magnetic yoke 111 and the N pole of the permanent magnet 101. The first S pole facing area indicates the facing area between the first magnetic yoke 111 and the S pole of the permanent magnet 101.

  The second N-pole facing area indicates the facing area between the second magnetic yoke 112 and the N pole of the permanent magnet 101. The second S-pole facing area indicates the facing area between the second magnetic yoke 112 and the S-pole of the permanent magnet 101.

  As shown in FIG. 8A, in the neutral state, the tip portion of the tooth portion 111A of the first magnetic yoke 111 and the tip portion of the tooth portion 112A of the second magnetic yoke 112 are the N pole and S of the permanent magnet 101. Located at the boundary with the pole. At this time, the first N pole facing area and the first S pole facing area are equal to each other. Further, the second N-pole facing area is equal to the second S-pole facing area. Thereby, no magnetic flux is generated between the magnetic flux collecting protrusions 53 of the first magnetic flux collecting ring 51 and the magnetic flux collecting protrusions 56 of the second magnetic flux collecting ring 54. For this reason, the output voltage of the magnetic sensor 41 indicates “0”.

  As shown in FIG. 8B, in the right rotation state, the torsion bar 13D (see FIG. 1) is twisted from the neutral state, so that the relative positions of the magnetic yokes 111 and 112 and the permanent magnet 101 are increased. Changes. Thereby, the first N pole facing area is larger than the first S pole facing area. Further, the second N-pole facing area is smaller than the second S-pole facing area. For this reason, the amount of magnetic flux entering the first magnetic yoke 111 from the N pole of the permanent magnet 101 is larger than the amount of magnetic flux emerging from the first magnetic yoke 111 toward the S pole of the permanent magnet 101. Further, the amount of magnetic flux entering the second magnetic yoke 112 from the N pole of the permanent magnet 101 is smaller than the amount of magnetic flux emerging from the second magnetic yoke 112 toward the S pole of the permanent magnet 101. For this reason, a magnetic flux flows from the magnetic flux collecting protrusion 53 of the first magnetic flux collecting ring 51 to the magnetic flux collecting protrusion 56 of the second magnetic flux collecting ring 54. The magnetic sensor 41 outputs a voltage corresponding to the magnetic flux.

  As shown in FIG. 8C, in the left rotation state, the torsion bar 13D is twisted in the opposite direction to the right rotation state, so that the relative positions of the magnetic yokes 111 and 112 and the permanent magnet 101 are increased. Changes in the opposite direction to when it is rotating clockwise. As a result, the first N-pole facing area is smaller than the first S-pole facing area. Further, the second N pole facing area is larger than the second S pole facing area. For this reason, the amount of magnetic flux entering the first magnetic yoke 111 from the N pole of the permanent magnet 101 is smaller than the amount of magnetic flux emerging from the first magnetic yoke 111 toward the S pole of the permanent magnet 101. Further, the amount of magnetic flux entering the second magnetic yoke 112 from the N pole of the permanent magnet 101 is larger than the amount of magnetic flux entering the S pole of the permanent magnet 101 from the second magnetic yoke 112. For this reason, a magnetic flux flows from the magnetic flux collecting protrusion 56 of the second magnetic flux collecting ring 54 to the magnetic flux collecting protrusion 53 of the first magnetic flux collecting ring 51. The magnetic sensor 41 outputs a voltage corresponding to the magnetic flux.

The steering device 1 of the present embodiment has the following effects.
(1) In the torque detection device 30, the end wall 77C of the magnetism collecting holder 70 has a protrusion 77E. According to this configuration, the corner portion 61B of the first shield end 61 of the magnetic shield 60 does not contact the side surface 77D of the end wall 77C of the magnetism collecting holder 70. Therefore, a large thermal stress is suppressed from being generated in the magnetic flux collecting holder 70 as the temperature of the torque detection device 30 changes. It should be noted that the second shield end 62 and the end wall 77C facing the shield end 62 have the same effect.

  (2) The magnetism collecting holder 70 has an end cover part 79. According to this configuration, the shield end portions 61 and 62 of the magnetic shield 60 are covered with the end cover component 79 from the outer direction ZB2. For this reason, the shield end portions 61 and 62 do not contact the inner surface 81 </ b> C of the sensor housing 80. Therefore, compared to the torque detection device 200, it is possible to suppress a large thermal stress from being generated on the inner surface 81C of the sensor housing 80.

  (3) The end cover part 79 has a protrusion 79A. According to this configuration, the shield end portions 61 and 62 of the magnetic shield 60 are pressed against the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70 by the projection 79 </ b> A. For this reason, the projection 79A is omitted from the end cover part 79, and compared with a configuration in which the shield end parts 61 and 62 are inserted between the end cover part 79 and the outer peripheral surface 70Y of the magnetism collecting holder 70. Thus, the position of each shield end 61, 62 in the radial direction ZB with respect to the magnetism collecting holder 70 can be accurately determined. Further, the projection 79A is omitted from the end cover component 79, and the shield end portions 61 and 62 are press-fitted into the outer peripheral surface 70Y of the end cover component 79 and the magnetism collecting holder 70. A person can easily attach the shield end portions 61 and 62 to the magnetism collecting holder 70.

  (4) The magnetism collecting holder 70 has a main body cover part 78. According to this configuration, the magnetic shield 60 is prevented from being separated from the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70. Therefore, it is possible to suppress a decrease in the function of reducing the influence of the magnetic flux collecting rings 51 and 54 from the external magnetic field due to the magnetic shield 60 and a decrease in the strength of the sensor housing 80.

  (5) The main body cover part 78 has a protrusion 78A. According to this configuration, the shield body 63 of the magnetic shield 60 is pressed against the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70 by the protrusion 78 </ b> A. For this reason, the projection 78A is omitted from the main body cover part 78, and the magnetism collecting holder is compared with the configuration in which the shield main body 63 is assumed to be inserted between the main body cover part 78 and the outer peripheral surface 70Y of the magnetism collecting holder 70. The position of the shield body 63 in the radial direction ZB relative to 70 can be accurately determined. Further, compared to the configuration in which the projection 78A is omitted from the main body cover part 78 and the shield main body 63 is press-fitted into the outer peripheral surface 70Y of the main body cover part 78 and the magnetism collecting holder 70, the operator can Can be easily attached to the magnetism collecting holder 70.

  (6) The protrusion 77E of the end wall 77C contacts over the entire axial direction ZA of the shield end surface 61A of the first shield end portion 61. According to this configuration, the contact pressure between the projection 77E and the shield end surface 61A is reduced as compared with the configuration in which the projection 77E is assumed to contact only a part of the shield end surface 61A in the axial direction ZA.

  (7) The protrusion 77E contacts the central portion of the shield end surface 61A in the radial direction ZB. According to this configuration, contact between the projection 77E and the corner portion 61B of the first shield end 61 is avoided. For this reason, it is suppressed that a big thermal stress is applied to the magnetism collecting holder 70 through the protrusion 77E according to the temperature change of the torque detection device 30.

  (8) The protrusion 78A of the main body cover part 78 is formed over the entire circumferential direction ZC of the main body cover part 78. According to this configuration, a wider range of the outer peripheral surface 60Y of the magnetic shield 60 can be pressed by the protrusion 78A. For this reason, for example, the magnetic shield 60 such as a shape in which the magnetic shield 60 is separated from the outer peripheral surface 70Y of the magnetic flux collecting holder 70 is prevented from being held in the magnetic flux collecting holder 70 in an inappropriate shape.

  (9) A plurality of main body cover parts 78 are formed in the circumferential direction ZC. According to this configuration, the magnetic shield 60 is held in the magnetic flux collecting holder 70 in a more appropriate shape as compared with the configuration assumed that the single main body cover part 78 is formed.

  (10) The protrusion 79A of the end cover part 79 is formed from the upper wall 77A to the lower wall 77B of the magnetism collecting holder 70. According to this configuration, the molding material of the sensor housing 80 does not flow into the closed space S. For this reason, the contact between the sensor housing 80 and the shield end portions 61 and 62 can be suppressed.

  (11) The protrusion 78A of the main body cover part 78 is formed in a semicircular shape. According to this configuration, when the operator inserts the magnetic shield 60 between the main body cover part 78 and the outer peripheral surface 70Y of the magnetism collecting holder 70, an angle formed by the outer peripheral surface 60Y and the lower end surface of the magnetic shield 60. The portion comes into contact with the protrusion 78 </ b> A and is guided between the main body cover part 78 and the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70. Therefore, the operator can easily assemble the magnetic shield 60 to the magnetic flux collecting holder 70.

  (12) The protrusion 79A of the end cover part 79 is formed in a semicircular shape. According to this configuration, when the operator inserts the first shield end portion 61 between the end cover component 79 and the outer peripheral surface 70Y of the magnetism collecting holder 70, the corner portion 61B contacts the protrusion 79A and the end portion It is guided between the cover part 79 and the outer peripheral surface 70Y of the magnetism collecting holder 70. Therefore, the operator can easily assemble the magnetic shield 60 to the magnetic flux collecting holder 70. Note that the end cover component 79 also has the same effect with respect to the second shield end 62.

  (13) The end cover part 79 is formed of the same material as the resin material of the sensor housing 80. According to this configuration, the difference between the linear expansion coefficient of the end cover part 79 and the linear expansion coefficient of the sensor housing 80 is eliminated. For this reason, application of thermal stress to the sensor housing 80 by the end cover component 79 is suppressed.

  The steering apparatus includes an embodiment different from the above embodiment. Hereinafter, modifications of the above-described embodiment as other embodiments of the steering apparatus will be described. The following modifications can be combined with each other.

  In the magnetic flux collecting holder 70 of the embodiment, the projection 77E is formed on the end wall 77C. On the other hand, as shown in FIG. 9A, the magnetic flux collecting holder 70 of the modified example has the protrusion 77E omitted from the end wall 77C. The magnetic flux collecting holder 70 according to the modified example has an end wall 77C formed only at the central portion of the magnetic flux collecting holder 70 in the axial direction ZA. That is, the modified end wall 77C is separated from the upper wall 77A and the lower wall 77B in the axial direction ZA. In the magnetic flux collecting unit 50 of the modified example, the corner portion 61C in the axial direction ZA of the first shield end portion 61 of the magnetic shield 60 does not contact the end wall 77C. The corner portion 61 </ b> C is configured as a connection portion between the shield end surface 61 </ b> A of the first shield end portion 61 and the upper end surface of the magnetic shield 60, and a connection portion between the shield end surface 61 </ b> A and the projecting end surface of the magnetic shield 60. Further, the second shield end portion 62 and the end wall 77C facing the shield end portion 62 can be similarly changed.

  Further, as shown in FIG. 9 (b), the magnetic flux collecting holder 70 of another modified example has a protrusion 77E omitted from the end wall 77C, and is surrounded at both end portions in the axial direction ZA of the side surface 77D of the end wall 77C. A recess 77F that is recessed in the direction ZC is formed. In the magnetic flux collecting unit 50 of another modification, the corner portion 61C in the axial direction ZA of the first shield end 61 of the magnetic shield 60 does not contact the end wall 77C. The second shield end 62 and the end wall 77C facing the shield end 62 can be similarly changed.

  The end wall 77C of the embodiment has a protrusion 77E formed from the upper wall 77A to the lower wall 77B in the axial direction ZA. On the other hand, the end wall 77C of the modified example has a protrusion 77E formed only in the central portion of the end wall 77C in the axial direction ZA. That is, the projection 77E of the modification is separated from the upper wall 77A and the lower wall 77B in the axial direction ZA. In the magnetic flux collecting unit 50 of the modified example, both end portions in the axial direction ZA of the shield end portions 61 and 62 of the magnetic shield 60 do not contact the protrusion 77E.

The magnetic flux collecting holder 70 according to the embodiment has three main body cover parts 78. On the other hand, the magnetism collecting holder 70 according to the modification has one, two, or four or more main body cover parts 78.
The magnetic flux collecting unit 50 of the embodiment has a configuration in which the magnetic flux collecting holder 70 and the main body cover component 78 are integrally formed. On the other hand, the magnetism collecting unit 50 of the modified example has a configuration in which the magnetism collecting holder 70 and the main body cover part 78 are individually formed. The main body cover part 78 of the modified example is fixed to the outer peripheral surface of the upper wall 77A of the magnetism collecting holder 70 by welding or the like. The main body cover part 78 of the modification may be formed of a material different from the resin material of the magnetic flux collecting holder 70.

  The main body cover part 78 of the embodiment extends from the upper wall 77A of the magnetism collecting holder 70 in the downward direction ZA2. On the other hand, the main body cover part 78 of the modification extends from the lower wall 77B of the magnetism collecting holder 70 in the upward direction ZA1.

  The main body cover part 78 of the embodiment has one protrusion 78A. On the other hand, the main body cover part 78 of the modified example has a plurality of protrusions 78A. The modified projections 78A are arranged in the circumferential direction ZC. Moreover, the main body cover part 78 of another modified example does not have the protrusion 78A.

  In the main body cover part 78 of the embodiment, the dimension of the protrusion 78A in the circumferential direction ZC is equal to the dimension of the main body cover part 78 in the circumferential direction ZC. On the other hand, in the main body cover part 78 of the modified example, the dimension of the protrusion 78A in the circumferential direction ZC is smaller than the dimension of the main body cover part 78 in the circumferential direction ZC.

  -The main body cover part 78 of embodiment has the semicircle-shaped protrusion 78A in the side view of the circumferential direction ZC. On the other hand, the main body cover part 78 of the modified example has a projection 78A formed as an elliptical shape in a side view in the circumferential direction ZC or an inclined surface that inclines in the inward direction ZB1 toward the upward direction ZA1. In short, the protrusion 78A may have any shape that can guide the shield main body 63 of the magnetic shield 60 between the main body cover part 78 and the outer peripheral surface 70Y of the magnetism collecting holder 70.

  In the embodiment, the end cover part 79 is formed of the same material as the resin material of the sensor housing 80. On the other hand, the end cover part 79 of the modified example is formed of a material different from the resin material of the sensor housing 80. In the modified end cover part 79, the difference between the linear expansion coefficient of the magnetic shield 60 and the linear expansion coefficient of the end cover part 79 is based on the difference between the linear expansion coefficient of the magnetic shield 60 and the linear expansion coefficient of the sensor housing 80. Preferably, it is formed of a material that becomes smaller.

The end cover component 79 of the embodiment is formed separately from the magnetic flux collecting holder 70. On the other hand, the end cover part 79 of the modified example is formed integrally with the magnetism collecting holder 70.
The end cover part 79 of the embodiment has a protrusion 79A. On the other hand, the end cover part 79 of the modification has a plurality of protrusions 79A. The modified projections 79A are arranged in the axial direction ZA. Further, the end cover part 79 of another modified example does not have the protrusion 79A.

  The end cover component 79 of the embodiment has a semicircular protrusion 79A in plan view. On the other hand, the end cover part 79 of the modified example has a projection 79A formed as an elliptical shape in a plan view or an inclined surface inclined in the inward direction ZB1 toward the end wall 77C in the circumferential direction ZC. In short, the projection 79 </ b> A may have any shape that can guide the shield end portions 61 and 62 of the magnetic shield 60 between the end cover component 79 and the outer peripheral surface 70 </ b> Y of the magnetism collecting holder 70.

  The magnetic flux collecting holder 70 of the embodiment has a main body cover part 78 and an end cover part 79. On the other hand, the magnetism collecting holder 70 of the modified example has either the main body cover part 78 or the end cover part 79. Further, the magnetic flux collecting holder 70 of another modified example does not have the main body cover part 78 and the end cover part 79.

  In the magnetic flux collecting holder 70 of the above modification, when the end cover component 79 is not provided, the closed space S includes the end wall 77C, the protrusion 77E, the outer peripheral surface 70Y of the magnetic flux collecting holder 70, and the first shield end portion 61. Is formed by a corner portion 61B on the inner direction ZB1 side. For this reason, in the magnetic flux collecting holder 70 of the above-described modified example, it is avoided that the corner portion 61B of the first shield end 61 on the side of the inward ZB1 side presses the side surface 77D of the end wall 77C due to the temperature change of the torque detection device 30. Is done. For this reason, it is suppressed that a big thermal stress is applied to the magnetism collecting holder 70 with the temperature change of the torque detector 30.

  The magnetic flux collecting holder 70 according to the embodiment is formed of the same resin material as that of the sensor housing 80. On the other hand, the magnetism collecting holder 70 of the modified example is formed of a resin material different from that of the sensor housing 80.

  The magnetic flux collecting unit 50 of the embodiment has one magnetic shield 60. On the other hand, the magnetic flux collecting unit 50 of the modified example has a magnetic shield divided into a plurality of pieces in the axial direction ZA. In the magnetic flux collecting holder 70 of the modified example, a projection 77E is formed on a side surface 77D of the end wall 77C that faces the shield end surface of each magnetic shield in the circumferential direction ZC.

  The first magnetism collecting ring 51 of the embodiment has a separation portion 52A. On the other hand, the first magnetism collecting ring 51 of the modified example does not have the separation portion 52A. That is, the first magnetism collecting ring 51 of the modified example has an annular shape.

  -The 2nd magnetism collecting ring 54 of embodiment has separation part 55A. On the other hand, the second magnetism collecting ring 54 of the modified example does not have the separation portion 55A. That is, the second magnetism collecting ring 54 of the modification has an annular shape.

  In the magnetic flux collecting unit 50 of the embodiment, the magnetic flux collecting rings 51 and 54 are attached to the holding convex portion 71 of the magnetic flux collecting holder 70. On the other hand, in the magnetism collecting unit 50 of the modified example, the magnetism collecting holder 70 is formed integrally with the magnetism collecting rings 51 and 54. The magnetism collecting holder 70 of the modified example does not have the holding convex portion 71, the upper through hole 74, and the lower through hole 75.

  The torque detection device 30 according to the embodiment has two magnetic sensors 41. On the other hand, the torque detection device 30 of the modified example has one magnetic sensor 41. The first magnetism collecting ring 51 of the modified example has one magnetism collecting protrusion 53. The modified second magnetic flux collecting ring 54 has one magnetic flux collecting projection 56. In addition, the torque detection device 30 of another modified example includes a Hall element or an MR element as the magnetic sensor 41 instead of the Hall IC.

  -Steering device 1 of an embodiment has composition as a dual pinion assist type electric power steering device. On the other hand, the steering device 1 of the modified example has a configuration as a column assist type, pinion assist type, rack parallel type, or rack coaxial type electric power steering device.

  The steering device 1 of the embodiment has a configuration as an electric power steering device having the assist device 20. On the other hand, the steering device 1 according to the modification has a configuration as a mechanical steering device in which the assist device 20 is omitted.

  In short, as long as the steering device has a rack shaft and a pinion shaft, the present invention can be applied to an electric power steering device other than the dual pinion assist type and a steering device other than the electric power steering device.

  ZA ... axial direction, ZA1 ... upward direction, ZA2 ... downward direction, ZB ... radial direction, ZB1 ... inward direction, ZB2 ... outer direction, ZC ... circumferential direction, S ... closed space, 1 ... steering device, 2 ... steering wheel, DESCRIPTION OF SYMBOLS 3 ... Steering wheel, 10 ... Steering device, 11 ... Column shaft, 12 ... Intermediate shaft, 13 ... Pinion shaft, 13A ... 1st shaft, 13B ... 2nd shaft, 13C ... Pinion gear, 13D ... Torsion bar, 14 ... Rack Shaft, 14A ... 1st gear part, 14B ... 2nd gear part, 15 ... Rack and pinion mechanism, 16 ... Tie rod, 17 ... Rack housing, 17A ... Fixed component, 20 ... Assist device, 21 ... Assist motor, 22 ... Worm Shaft, 23 ... Worm wheel, 24 ... Pinion shaft, 24A ... Pinion gear , 30 ... Torque detection device, 31 ... Oil seal, 32 ... O-ring, 40 ... Sensor unit, 41 ... Magnetic sensor, 50 ... Magnetic flux collecting unit, 51 ... First magnetic flux collecting ring, 52 ... Ring body, 52A ... Spacing part 53 ... Magnetic flux collecting projection, 54 ... Second magnetic flux collecting ring, 55 ... Ring body, 55A ... Separating portion, 56 ... Magnetic flux collecting projection, 60 ... Magnetic shield, 60X ... Inner circumferential surface, 60Y ... Outer circumferential surface, 61 ... First 1 shield end portion, 61A ... shield end surface, 61B ... corner portion, 61C ... corner portion, 62 ... second shield end portion, 63 ... shield body, 64 ... separated portion, 70 ... magnet collecting holder, 70X ... inner peripheral surface, 70Y ... outer peripheral surface, 71 ... holding convex part, 72 ... first holding part, 73 ... second holding part, 74 ... upper through hole, 75 ... lower through hole, 76 ... insertion part, 76A ... insertion hole, 76B ... Upper projection, 76C ... Side projection, 77 ... Shield holding portion, 77A ... Upper wall, 77B ... Lower wall, 77C ... End wall, 77D ... Side, 77E ... Protrusion, 77F ... Recess, 78 ... Body cover part, 78A ... Protrusion, 79 ... End Cover part, 79A ... protrusion, 80 ... sensor housing, 81 ... housing body, 81A ... base part, 81B ... magnetism collecting housing part, 81C ... inner surface, 82 ... board support part, 83 ... board mounting part, 84 ... device mounting part , 85 ... Internal space, 90 ... Circuit unit, 91 ... Circuit board, 100 ... Magnet unit, 101 ... Permanent magnet, 102 ... Core, 110 ... Magnetic yoke unit, 111 ... First magnetic yoke, 111A ... Tooth part, 111B ... Connection part 112 ... second magnetic yoke 112A ... tooth part 112B ... connection part 113 ... yoke holder 114 ... intermediate part 200 ... torque detection device , 210 ... magnetic collecting unit, 211 ... magnetic collecting holder, 211A ... end wall, 211X ... inner peripheral surface, 211Y ... outer peripheral surface, 212 ... magnetic collecting ring, 213 ... magnetic shield, 213A ... shield end, 213B ... square 213X ... inner peripheral surface, 213Y ... outer peripheral surface, 220 ... sensor housing, 211 ... inner surface.

Claims (7)

With permanent magnets,
A magnetic yoke disposed in a magnetic field formed by the permanent magnet and changing a relative position with the permanent magnet;
A magnetic flux collecting holder that is formed in an annular shape by resin molding and surrounds the magnetic yoke, a magnetic flux collecting ring that is attached to the inner peripheral surface of the magnetic flux collecting holder and collects the magnetic flux of the magnetic yoke, and a metal plate that is formed by bending An annular current collector having a magnetic shield attached to the outer peripheral surface of the magnetic flux collecting holder, wherein at least one of the corner portions of the shield end that is the circumferential end of the magnetic shield is in a non-contact relationship with the magnetic flux collecting holder. A magnetic unit;
A magnetic sensor for detecting a magnetic flux of a magnetic circuit formed by the permanent magnet, the magnetic yoke, and the magnetism collecting ring;
A torque detection device comprising: a sensor housing formed integrally with the magnetic flux collecting unit by a resin poured into the outer peripheral side of the magnetic flux collecting unit. The magnetic flux collecting holder has two end walls extending from the outer peripheral surface of the magnetic flux collecting holder in the radial direction of the magnetic flux collecting holder and spaced apart from each other in the circumferential direction of the magnetic flux collecting holder;
A shield end surface that is an end surface of the shield end in the circumferential direction of the magnetic shield is opposed to a side surface of the end wall;
The torque detection device according to claim 1, wherein the magnetic flux collecting unit has a protrusion extending from the side surface of the end wall toward the shield end surface. The torque detection device according to claim 1, wherein the magnetism collecting holder has an end cover part that covers the shield end from the side opposite to the outer peripheral surface of the magnetism collecting holder. The end cover component has a protrusion extending toward the shield end,
The torque detection device according to claim 3, wherein the protrusion is in contact with the shield end. The torque detection device according to any one of claims 1 to 4, wherein the magnetism collecting holder includes a body cover part that covers a part of a shield body that connects the shield end portions from the outside. The body cover component has a protrusion extending toward the shield body,
The torque detection device according to claim 5, wherein the protrusion contacts the shield body.   A steering device comprising the torque detection device according to any one of claims 1 to 6.