Sensor device

Abstract

The present invention relates to a sensor device (24), which includes a partial assembly (44), a circuit board (43) and a sensor housing (45). The partial assembly (44) is formed by selectively mounting a portion of at least one of a magnetic collecting member (92) and a driven wheel (96, 97) to a retaining member (91). The circuit board (43) is provided with a detector (63, 64), which is configured to detect at least one of a magnetic flux induced by the magnetic collecting member and a rotation angle of the driven wheel according to the portion mounted to the retaining member (91). The sensor housing (45) is penetrated by a shaft (13) and accommodates the partial assembly (44) and the circuit board (43).

Description

Technical Field

[0001] The present invention relates to a sensor device. Background Art

[0002] So far, a sensor device described in Japanese Unexamined Patent Application Publication No. 2019-074364 (JP 2019-074364 A) is known. The sensor device detects a steering torque applied to a steering wheel and a rotation angle of a steering shaft connected to the steering wheel, that is, a steering angle. The sensor device is provided on a pinion shaft constituting the steering shaft. The pinion shaft is constituted by coupling an input shaft and an output shaft to each other via a torsion bar.

[0003] The sensor device has a permanent magnet fixed to an input shaft and a yoke unit fixed to an output shaft. The yoke unit is formed by integrating two yokes with each other via a resin portion. When the torsion bar is torsionally deformed by the torque applied to the input shaft, the respective relative positions of the permanent magnet and the yoke in the rotational direction change. The sensor device detects the torque applied to the torsion bar based on the change in the magnetic flux of the yoke, which is accompanied by the change in the respective relative positions of the permanent magnet and the yoke.

[0004] The sensor device includes an external gear that rotates together with the output shaft of the pinion shaft and two driven gears meshing with the external gear. The two driven gears have different numbers of teeth, so the rotation angles of the two driven gears during the rotation of the external gear are different from each other. The sensor device detects the rotation angles of the two driven gears and detects the rotation angle of the output shaft based on the detected rotation angles. Summary of the invention

[0005] The sensor housing of the sensor device according to JP 2019-074364 A has a first housing member and a second housing member. The first housing member accommodates a yoke unit including an external gear. The second housing member accommodates two driven gears and a circuit board. The circuit board is provided with electronic components such as a magnetic sensor for rotation angle detection and a magnetic sensor for torque detection. In addition, the second housing member is provided with a tubular connector fitting portion. The connector fitting portion is equipped with a connector for supplying power to the circuit board and transmitting signals to a controller.

[0006] There are many variations of the sensor device depending on the product specifications. For example, it is necessary to prepare various types of second housing components according to requirements for the shape of the connector fitting portion, the direction in which the connector and the connector fitting portion are fitted, etc. In addition, the second housing component and the first housing component together constitute the appearance of the housing, so it is necessary to prepare multiple variations of the first housing component and the second housing component according to requirements for the appearance of the sensor device.

[0007] The present invention suppresses an increase in the number of variations of constituent components.

[0008] One aspect of the present invention provides a sensor device. The sensor device includes a partial assembly, a circuit board, and a sensor housing. The partial assembly is constructed by selectively mounting a portion including at least one of a magnetic collecting member and a driven wheel to a retaining member. The magnetic collecting member is configured to sense a magnetic flux that matches the torsion of a shaft as a detection target. The driven wheel is configured to rotate as the shaft rotates. The circuit board is provided with a detector configured to detect at least one of the magnetic flux induced by the magnetic collecting member and the rotation angle of the driven wheel according to the component mounted to the retaining member. The sensor housing is penetrated by the shaft and accommodates the partial assembly and the circuit board.

[0009] With the above configuration, regardless of the requirements of the sensor device, the partial assembly can be constructed using the same parts by selectively changing the parts to be assembled into the partial assembly according to the detection function required by the sensor device. Therefore, the increase in the number of variations of the constituent parts of the partial assembly can be suppressed, and thus the increase in the number of variations of the constituent parts of the sensor device can be suppressed.

[0010] For example, in the case where the sensor device is required to detect both the torque applied to the shaft and the rotation angle of the shaft, both the magnetic collecting member and the driven wheel can be mounted to the retaining member. The magnetic flux induced by the magnetic collecting member matches the torsion of the shaft, so the torque acting on the shaft can be calculated based on the magnetic flux. At the same time, the driven wheel rotates as the shaft rotates, so the rotation angle of the shaft can be calculated based on the rotation angle of the driven wheel. In the case where the sensor device is required to detect only the torque applied to the shaft, only the magnetic collecting member can be mounted to the retaining member. At the same time, in the case where the sensor device is required to detect only the rotation angle of the shaft, only the driven wheel can be mounted to the retaining member.

[0011] It is also possible to conceive of a requirement for the shape or material of the sensor housing, and for such a requirement, only the shape or material of the sensor housing can be changed. Regardless of the shape or material of the sensor housing, the same partial components to be accommodated in the sensor housing can be used. Therefore, an increase in the number of variations of the constituent components of the sensor device can be suppressed.

[0012] In the above sensor device, the holder may include an engaging portion. The partial assembly may be held inside the sensor housing with the engaging portion engaging with a portion of the sensor housing.

[0013] With the above configuration, some components can be installed to the inside of the sensor housing with a single operation. In addition, some components can be suppressed from falling off from the sensor housing when assembling the sensor device.

[0014] In the above sensor device, the partial assembly may include a holding member for holding the driven wheel on the holding member. The holding member may be mounted to the holding member to cover the driven wheel.

[0015] With the above configuration, the driven wheel is held on the holder by the holding member. Therefore, the driven wheel is suppressed from falling off the holder. In addition, partial assembly can be easily handled.

[0016] In the above sensor device, the sensor housing may include a cover that closes an opening portion that opens in a direction intersecting the axis of the shaft. The cover may be provided on the assumption that the sensor housing includes an accommodation chamber that accommodates some components and the circuit board via the opening portion.

[0017] With the above configuration, the storage chamber is tightly closed when the opening is closed by the cover, thereby suppressing dust or liquid from entering the storage chamber. In addition, the partial assembly does not have a function as a sensor housing. Therefore, for example, unlike the case where the retaining member of the partial assembly constitutes a part of the sensor housing, the increase in the number of variations of the retaining member can be suppressed.

[0018] In the sensor device described above, the shaft can rotate with the operation of the steering wheel. This enables the torque applied to the shaft to be detected as the steering torque applied to the steering wheel, and the rotation angle of the shaft to be detected as the steering angle, which is the rotation angle of the steering wheel.

[0019] With the sensor device according to the present invention, it is possible to suppress an increase in the number of variations of constituent components. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and in which:

[0021] Figure 1 is a diagram of a steering device including a sensor device according to an embodiment;

[0022] Figure 2 is an exploded perspective view of a sensor device according to an embodiment;

[0023] Figure 3 is a cross-sectional view of a sensor device according to an embodiment taken along an axial direction;

[0024] Figure 4 is an exploded perspective view of some components according to an embodiment;

[0025] Figure 5A is a perspective view of a portion of components according to an embodiment;

[0026] Figure 5B is another perspective view of a portion of an assembly according to an embodiment;

[0027] Figure 5C is another perspective view of a portion of an assembly according to an embodiment;

[0028] Figure 6 is a bottom view of a partial assembly according to an embodiment when viewed from the opposite side of the gear stopper;

[0029] Figure 7 is a perspective view of a sensor housing according to an embodiment when viewed from the opening side;

[0030] Figure 8 is a side cross-sectional view of the sensor housing according to the embodiment, as viewed from the opening side, illustrating the main parts;

[0031] Fig. 9 is a cross-sectional view of a sensor device according to an embodiment when it is exploded into a sensor housing and a yoke;

[0032] Fig.10 The sensor housing is separate from the Figure 3 A cross-sectional view taken along line XX in FIG.

[0033] Fig.11 1 is a perspective view illustrating a positional relationship among a yoke, a magnetic flux collecting ring, and a core according to an embodiment. DETAILED DESCRIPTION

[0034] An embodiment in which the sensor is applied to a steering device of a vehicle will be described below. Figure 1 As shown in FIG. 1 , a steering device 10 of a vehicle has a steering shaft 12 coupled to a steering wheel 11. A pinion shaft 13 is provided at an end portion of the steering shaft 12 on the opposite side of the steering wheel 11. Pinion teeth 13a of the pinion shaft 13 mesh with rack teeth 14a of a steering shaft 14 extending in a direction intersecting the pinion shaft 13. Right and left steering wheels 16, 16 are coupled to respective ends of the steering shaft 14 via respective tie rods 15, 15.

[0035] The steering device 10 also includes a motor 21 , a speed reduction mechanism 22 , a pinion shaft 23 , a sensor device 24 , and a control device 25 as components for generating a steering assist force (assist force).

[0036] The motor 21 is a source of steering assist force, and the motor 21 may be, for example, a three-phase brushless motor. The motor 21 is coupled to the pinion shaft 23 via a speed reduction mechanism 22. The pinion teeth 23a of the pinion shaft 23 mesh with the rack teeth 14b of the steering shaft 14. The speed of rotation of the motor 21 is reduced by the speed reduction mechanism 22. The decelerated rotational force is transmitted from the pinion shaft 23 to the pinion shaft 13 via the steering shaft 14 as a steering assist force.

[0037] The sensor device 24 is provided on the pinion shaft 13 (specifically, provided on the gear housing that accommodates the pinion shaft 13 together with the steering shaft 14). The sensor device 24 is composed of a torque sensor and a rotation angle sensor in combination. The sensor device 24 detects the torque applied to the pinion shaft 13 by the operation of rotating the steering wheel 11 as the steering torque Th. The sensor device 24 also detects the rotation angle θpa of the pinion shaft 13 in multiple rotations exceeding 360° as the steering angle θs.

[0038] The control device 25 acquires the steering torque Th and the steering angle θs detected by the sensor device 24. The control device 25 also acquires the vehicle speed V detected by the vehicle speed sensor 26 provided in the vehicle. The control device 25 performs assist control for generating a steering assist force that matches the steering torque Th and the vehicle speed V by controlling the energization of the motor 21. The control device 25 controls the power supply to the motor 21 based on the steering torque Th detected by the sensor device 24 and the vehicle speed V detected by the vehicle speed sensor 26.

[0039] Next, the pinion shaft 13 and the sensor device 24 will be described. Figure 2 As shown in FIG. 1 , the pinion shaft 13 has an input shaft 31, a torsion bar 32, and an output shaft 33. The input shaft 31 and the output shaft 33 are coupled to each other via the torsion bar 32. The input shaft 31, the torsion bar 32, and the output shaft 33 are coaxially positioned on the axis O.

[0040] The sensor device 24 has a permanent magnet 41, a yoke 42, a circuit board 43, a partial assembly 44, a sensor housing 45, and a cover 46. The permanent magnet 41 has a cylindrical shape. The permanent magnet 41 has S poles and N poles alternately arranged along the circumferential direction of the permanent magnet 41. The permanent magnet 41 is fixed to the input shaft 31.

[0041] The yoke 42 has a cylindrical shape. The permanent magnet 41 is inserted into the yoke 42. The yoke 42 is formed by molding two annular yokes 51, 52 as magnetic bodies using a synthetic resin material. A portion of the yoke 42 formed of the synthetic resin material is used as a retaining member 53 for maintaining the positional relationship between the two yokes 51, 52. A main drive gear 54 is integrally molded at the end portion of the retaining member 53. The two yokes 51, 52 are arranged along the direction of the axis O along the pinion shaft 13. The yoke 42 is fixed to the output shaft 33.

[0042] The two yokes 51 and 52 are respectively provided with a plurality of teeth 51a and 52a at equal intervals along the circumferential direction. The teeth 51a and 52a extend toward opposite sides relative to each other in the direction along the axis O of the pinion shaft 13. The two yokes 51 and 52 are maintained so that the respective teeth 51a and 52a are alternately positioned in the circumferential direction. The two yokes 51 and 52 are arranged so that the respective centers of the plurality of teeth 51a and 52a in the circumferential direction coincide with the boundary between the N pole and the S pole of the permanent magnet 41 when the torsion bar 32 is not torsionally deformed.

[0043] The circuit board 43 has a rectangular shape. Three support holes 61 are arranged in a row near the center of the circuit board 43. The circuit board 43 is also provided with a plurality of terminal connection holes 62. The terminal connection holes 62 are arranged in two rows along one of the two long side edges of the circuit board 43. In addition, on one surface ( Figure 2 Two magnetic sensors 63, 64 and two magnetic sensors 65, 66 are provided on the upper surface of the circuit board 43, the two magnetic sensors 63, 64 are detectors for angle detection, and the two magnetic sensors 65, 66 are detectors for torque detection. The magnetic sensors 63, 64 and the magnetic sensors 65, 66 are arranged in a row along the long side edge of the circuit board 43 on the opposite side of the long side edge where the terminal connection hole 62 is arranged. The two magnetic sensors 65, 66 for torque detection are positioned between the two magnetic sensors 63, 64 for angle detection in the direction in which such magnetic sensors are arranged. The magnetic sensors 63, 64 for angle detection may be, for example, magnetoresistive (MR) sensors. The magnetic sensors 65, 66 for torque detection may be, for example, Hall sensors.

[0044] The partial assembly 44 is formed by attaching a portion for detecting the rotation angle of the pinion shaft 13 and a portion for detecting the torque applied to the pinion shaft 13 to the holder 91 so as to be able to operate collectively. The configuration and assembly process of the partial assembly 44 will be discussed in detail later.

[0045] The sensor housing 45 is integrally molded from a synthetic resin material. The sensor housing 45 has a tubular shape that is open toward a direction intersecting the axis O of the pinion shaft 13. The sensor housing 45 is penetrated by the pinion shaft 13. In addition, the sensor housing 45 accommodates the permanent magnet 41 and the yoke 42 provided on the pinion shaft 13, as well as the circuit board 43 and a partial assembly 44 in the sensor housing 45.

[0046] The sensor housing 45 has a circular insertion hole 71, a tubular first accommodating chamber 72, and a second accommodating chamber 73. The insertion hole 71, the first accommodating chamber 72, and the second accommodating chamber 73 are connected to each other. The inner diameter of the insertion hole 71 is set to be slightly larger than the outer diameter of the pinion shaft 13. The inner diameter of the first accommodating chamber 72 is set to be slightly larger than the outer diameter of the yoke 42. The insertion hole 71 and the first accommodating chamber 72 are coaxially positioned on the axis O. The second accommodating chamber 73 is open in a direction intersecting with the axis O of the pinion shaft 13. The opening 73a of the second accommodating chamber 73 is closed by the cover 46, and thus the sensor housing 45 is closed.

[0047] Three support protrusions 74 in a stepped cylindrical shape are provided on the inner bottom surface of the second accommodation chamber 73. The three support protrusions 74 are arranged in a row along the width direction of the second accommodation chamber 73 orthogonal to the axis O. The three support protrusions 74 correspond to the three support holes 61 provided in the circuit board 43.

[0048] In addition, a plurality of terminals 75 are provided to protrude from the inner bottom surface of the second accommodating chamber 73. The plurality of terminals 75 are positioned outside relative to the supporting protrusion 74 in the opening direction of the second accommodating chamber 73. The plurality of terminals 75 are arranged in two rows along the width direction of the second accommodating chamber 73. The plurality of terminals 75 correspond to the plurality of terminal connection holes 62 provided in the circuit board 43.

[0049] In addition, a connector fitting portion 76 in a rectangular tubular shape is provided on the outer bottom surface of the second accommodating chamber 73. The connector fitting portion 76 extends along the axis O of the pinion shaft 13. A plurality of terminals 75 penetrate the bottom wall of the second accommodating chamber 73 to be exposed inside the connector fitting portion 76. The connector fitting portion 76 is fitted with a connector for wiring that electrically connects the terminals 75 of the circuit board 43 and the control device 25.

[0050] In addition, in the sensor housing 45, two C-shaped magnetism collecting rings 81, 82 are provided on the inner peripheral surface of the first accommodating chamber 72. The magnetism collecting rings 81, 82 are arranged in the direction along the axis O of the pinion shaft 13. The magnetism collecting ring 81 corresponds to the yoke 51. The magnetism collecting ring 82 corresponds to the yoke 52. The magnetism collecting ring 82 is provided with two magnetism collecting protrusions 81a, 81b. The magnetism collecting protrusions 81a, 81b are exposed to the interior of the second accommodating chamber 73.

[0051] like Figure 3 As shown in , the sensor housing 45 is attached to the gear housing 17 that accommodates the steering shaft 14. The first accommodation chamber 72 accommodates the yoke 42 attached to the pinion shaft 13. At the same time, the second accommodation chamber 73 accommodates the circuit board 43 and the partial assembly 44. The assembly process for the sensor device 24 will be discussed in detail later.

[0052] Next, the partial component 44 will be described in detail. Figure 4 As shown in FIG. 4 , the partial assembly 44 has a retaining member 91 , a core 92 serving as a magnetic collecting member, two magnetic shields 93 , 94 , a torsion coil spring 95 , two driven gears 96 , 97 serving as driven wheels, and a gear stopper 98 serving as a retaining member.

[0053] The retaining member 91 is integrally molded from a synthetic resin material. The retaining member 91 has a rectangular plate shape as a whole. The retaining member 91 has two support holes 101, 102. The support holes 101, 102 are arranged along the long side direction of the retaining member 91. The support holes 101, 102 are so-called long holes. The support holes 101, 102 are arranged to extend along the radial direction of the main drive gear 54 provided in the yoke 42 when the sensor device 24 is assembled, and are arranged to be farther away from each other at a position farther away from the main drive gear 54.

[0054] In addition, the holder 91 is provided with a support portion 103 in a cylindrical shape. The support portion 103 is provided on one of two surfaces of the holder 91 located on opposite sides relative to each other in the penetration direction of the support holes 101, 102 ( Figure 4 The support portion 103 is positioned between the two support holes 101 and 102 in the long side direction of the retaining member 91.

[0055] The retaining member 91 is also provided with two engaging protrusions 104, 105 serving as engaging portions. The engaging protrusions 104, 105 are provided on two short side surfaces of the retaining member 91 located on opposite sides relative to each other in the long side direction of the retaining member 91. The engaging protrusions 104, 105 are provided to correspond to two corner portions located on opposite sides relative to each other in the long side direction of the retaining member 91 among the four corners of the retaining member 91. The engaging protrusions 104, 105 have the shape of a U-shaped plate.

[0056] The retaining member 91 is also provided with a thin-walled portion 106. The thin-walled portion 106 is provided at a portion of the retaining member 91 located on the opposite side of the engaging protrusions 104, 105 in the short side direction of the retaining member 91. The thin-walled portion 106 is positioned at the center of the retaining member 91 in the long side direction. The thickness of the thin-walled portion 106 is set to be smaller than the thickness of other portions of the retaining member 91. The thin-walled portion 106 is provided with three fixing holes 107. The three fixing holes 107 are arranged along the long side direction of the retaining member 91. The three fixing holes 107 correspond to the three support holes 61 of the circuit board 43.

[0057] The core 92 is integrally provided with the retaining member 91 by resin molding. The core 92 is formed by plastically deforming a single metal plate material. The core 92 has two arm portions 111a, 111b, a connecting portion 112 and two magnetic collecting protrusions 113a, 113b. The two arm portions 111a, 111b have an arc surface shape. The two arm portions 111a, 111b are bent along the outer peripheral surface of the magnetic collecting ring 82 when the sensor device 24 is assembled. The connecting portion 112 connects the two arm portions 111a, 111b to each other, and the connecting portion 112 has a rectangular plate shape. Two magnetic collecting protrusions 113a, 113b are provided on the connecting portion 112. The two magnetic collecting protrusions 113a, 113b extend in opposite directions of the two arm portions 111a, 111b. The two magnetic collecting protrusions 113a, 113b are arranged along the direction in which the connecting portion 112 extends.

[0058] The two magnetic shields 93, 94 are provided integrally with the holder 91 by resin molding. The two magnetic shields 93, 94 are provided on the respective inner peripheral surfaces of the two support holes 101, 102 of the holder 91. The magnetic shields 93, 94 are made of a metal material and have a tubular shape along the respective inner peripheral surfaces of the support holes 101, 102.

[0059] The torsion coil spring 95 is mounted to the holder 91. The torsion coil spring 95 has a coil portion 121, a first arm portion 122, and a second arm portion 123. The coil portion 121 is fitted with the support portion 103 of the holder 91. The respective lengths of the first arm portion 122 and the second arm portion 123 are set to such lengths that the respective distal ends of the first arm portion 122 and the second arm portion 123 face the two support holes 101, 102 of the holder 91 in the axial direction of the support holes 101, 102 when the coil portion 121 is fitted with the support portion 103 of the holder 91.

[0060] The driven gear 96 has a gear portion 131 in the shape of a circular plate, a shaft portion 132 in the shape of a cylindrical column, and a permanent magnet 133 in the shape of a circular plate. The gear portion 131 and the shaft portion 132 are made of a synthetic resin material and are molded integrally with each other. The outer diameter of the shaft portion 132 is set to be smaller than the outer diameter of the gear portion 131. The gear portion 131 and the shaft portion 132 are coaxially positioned. The permanent magnet 133 is embedded in the end portion of the shaft portion 132 located on the opposite side of the gear portion 131. The permanent magnet 133 is integrally provided with the gear portion 131 and the shaft portion 132 by resin molding. Like the driven gear 96, the driven gear 97 has a gear portion 134, a shaft portion 135, and a permanent magnet 136. The permanent magnet 136 is embedded in the end portion of the shaft portion 135 located on the opposite side of the gear portion 134. The shaft portion 132 of the driven gear 96 is inserted into the support hole 101 of the retaining member 91. The shaft portion 135 of the driven gear 97 is inserted into the support hole 102 of the holder 91. When the shaft portions 132 and 135 are respectively inserted into the support holes 101 and 102, the gear portions 131 and 134 are supported so as to be able to move relative to the surface ( Figure 4 The gear parts 131 and 134 have different numbers of teeth.

[0061] The gear stopper 98 is made of a synthetic resin material and has a flat plate shape. The gear stopper 98 is attached to the retaining member 91. The gear stopper 98 covers the two driven gears 96, 97 and the torsion coil spring 95 mounted to the retaining member 91. The gear stopper 98 has a retaining portion 141 in the shape of a rectangular plate and four engaging lugs 142, 143, 144, 145. These four engaging lugs 142 to 145 are arranged at the four corners of the retaining portion 141. In addition, these four engaging lugs 142 to 145 extend in a direction orthogonal to the retaining portion 141. Engaging protrusions 142a, 143a, 144a, 145a are provided at the respective distal ends of these four engaging lugs 142 to 145. These four engaging protrusions 142a to 145a can engage with the four corners of the surface of the retaining member 91 located on the opposite side of the gear stopper 98.

[0062] Assembly process of some components

[0063] Next, description will be given of an assembling process of the partial assembly 44. However, it should be noted that the core 92 and the magnetic shields 93, 94 are provided integrally with the holder 91 by resin molding.

[0064] In order to assemble the partial assembly 44, first, the torsion coil spring 95 is attached to the holder 91 by fitting the coil portion 121 of the torsion coil spring 95 with the support portion 103 of the holder 91. Next, the shaft portions 132, 135 of the two driven gears 96, 97 are respectively inserted into the two support holes 101, 102 of the holder 91. Thus, the two driven gears 96, 97 are supported so as to be rotatable relative to the holder 91. Thereafter, the gear stopper 98 is attached to the holder 91 from the driven gears 96, 97 side.

[0065] like Figure 5A , Figure 5B and Figure 5C As shown in FIG. 1 , the four engaging lugs 142 to 145 of the gear stopper 98 are engaged with the four corners of the surface of the holder 91 on the opposite side of the gear stopper 98, so that when the holding portion 141 of the gear stopper 98 contacts the respective gear portions 131, 134 of the driven gears 96, 97, the gear stopper 98 is restricted from moving in the direction in which the gear stopper 98 will be disengaged from the holder 91. Therefore, the gear stopper 98 is fixed to the holder 91. In addition, the driven gears 96, 97 are held by the holder 91.

[0066] The assembly of the partial assembly 44 is completed as described above. Figure 5A , Figure 5B and Figure 5C As shown in FIG. 4 , when the partial assembly 44 is assembled, the torsion coil spring 95 and the two driven gears 96 and 97 are kept covered by the retaining portion 141. By making the gear portions 131 and 134 abut against the retaining portion 141 of the gear stopper 98, the two driven gears 96 and 97 are restricted from moving in a direction away from the retaining member 91 ( Figure 5A , Figure 5B and Figure 5C The driven gears 96 and 97 can slide and rotate relative to the holding portion 141 of the gear stopper 98 via the gear portions 131 and 134.

[0067] like Figure 5C As shown in FIG. 1 , the two driven gears 96 and 97 slightly protrude from the side edge portion of the gear stopper 98 located on the opposite side of the thin-walled portion 106 of the retainer 91. Figure 5A and Figure 5B As shown in FIG. 1 , in a state where the partial assembly 44 is assembled, the core 92 is exposed from one of the two long side surfaces of the holder 91 that is located on the opposite side to the thin-walled portion 106 .

[0068] like Figure 6As shown in , when the partial assembly 44 is assembled, the driven gears 96, 97 can move along the support holes 101, 102, respectively. The driven gears 96, 97 can move between a first position P1 and a second position P2 respectively located in the support holes 101, 102. The first position P1 is a position where the shaft portions 132, 135 are respectively engaged with the first end portions of the support holes 101, 102 via the magnetic shields 93, 94, which are the end portions on the side closer to the main drive gear 54. The second position P2 is a position where the shaft portions 132, 135 are respectively engaged with the second end portions of the support holes 101, 102 via the magnetic shields 93, 94, which are the end portions on the side farther from the main drive gear 54.

[0069] In addition, when the partial assembly 44 is assembled, the first arm portion 122 of the torsion coil spring 95 is engaged with the portion of the shaft portion 132 of the driven gear 96 located on the opposite side of the main drive gear 54. The second arm portion 123 is engaged with the portion of the shaft portion 135 of the driven gear 97 located on the opposite side of the main drive gear 54. The driven gears 96 and 97 are always biased toward the end portions of the support holes 101 and 102 located on the side close to the main drive gear 54 by the elastic force of the torsion coil spring 95. The movement of the driven gears 96 and 97 toward the first position P1 is restricted by the shaft portions 132 and 135 being engaged with the end portions of the support holes 101 and 102 located on the side close to the main drive gear 54 via the magnetic shields 93 and 94, respectively. The two magnetic collecting protrusions 113a and 113b of the core 92 are exposed from the side surface of the retainer 91 located on the opposite side of the gear stopper 98. The two magnetic flux collecting protrusions 113 a and 113 b are located between the two supporting holes 101 and 102 of the holder 91 .

[0070] Supplementary information on the sensor housing

[0071] Some additional descriptions are given to the sensor housing 45. Figure 7 As shown in the figure, a reinforcing member 151 in the shape of a rectangular plate is provided inside the sensor housing 45. The reinforcing member 151 is located at the boundary portion between the first accommodating chamber 72 and the second accommodating chamber 73 inside the sensor housing 45. In addition, when the sensor housing 45 is observed from the side of the opening portion 73a, the reinforcing member 151 is positioned at the center of the second accommodating chamber 73 in the width direction. The term "width direction" refers to the direction of the front face of the opening portion 73a that is orthogonal to the axis O of the pinion shaft 13. The reinforcing member 151 is provided to connect the two inner wall surfaces of the second accommodating chamber 73 that are opposite to each other along the direction of the axis O of the pinion shaft 13.

[0072] In addition, two engaging protrusions 152, 153 are provided inside the second accommodating chamber 73 of the sensor housing 45. The engaging protrusions 152, 153 are provided on two corresponding inner side surfaces of the second accommodating chamber 73 that are opposite to each other in a direction orthogonal to the axis O of the pinion shaft 13. The engaging protrusions 152, 153 are provided to hold the partial assembly 44 inserted into the second accommodating chamber 73 via the opening 73a inside the second accommodating chamber 73, and are provided to correspond to the engaging protrusions 104, 105 provided on the retaining member 91 of the partial assembly 44, respectively.

[0073] Sensor device assembly process

[0074] Next, the assembly process of the sensor device 24 will be described. However, it should be noted that the partial assembly 44 has already been assembled. In addition, the yoke 42 has already been attached to the pinion shaft 13.

[0075] As mentioned earlier in Figure 2 As shown in FIG. 2 , in order to assemble the sensor device 24, first, the circuit board 43 is attached to the inside of the second accommodating chamber 73 via the opening portion 73a of the sensor housing 45. However, it should be noted that the circuit board 43 is attached to the inner bottom surface of the second accommodating chamber 73 in a posture such that the two magnetic sensors 63, 64 for angle detection and the two magnetic sensors 65, 66 for torque detection face the opposite side of the inner bottom surface of the second accommodating chamber 73 ( Figure 2 ).

[0076] At this time, the support hole 61 of the circuit board 43 is penetrated by the corresponding support protrusion 74 provided on the inner bottom surface of the second accommodation chamber 73. In addition, at this time, the terminal connection hole 62 of the circuit board 43 is penetrated by the corresponding terminal 75 protruding from the inner bottom surface of the second accommodation chamber 73. Then, soldering or the like is performed with the terminal 75 inserted into the corresponding terminal connection hole 62 of the circuit board 43. Therefore, the wiring pattern (not shown) on the circuit board 43 and the terminal 75 are electrically connected to each other.

[0077] Next, the subassembly 44 is mounted to the inside of the second storage chamber 73 via the opening 73a of the sensor housing 45. At this time, the subassembly 44 is attached to the inside of the second storage chamber 73 in the following manner: the subassembly 44 is stacked on the circuit board 43 while the drive gears 96, 97 are maintained in a posture facing the first storage chamber 72 side of the sensor housing 45.

[0078] When the partial components 44 are Figure 8When the part assembly 44 is installed in the second accommodating chamber 73 as shown in the figure, the two engaging protrusions 104 and 105 provided on the retaining member 91 of the part assembly 44 engage with the two engaging protrusions 152 and 153 provided in the second accommodating chamber 73, thereby limiting the movement of the part assembly 44 in the direction away from the circuit board 43 ( Figure 8 Therefore, the movement of the partial assembly 44 in the direction away from the circuit board 43 is restricted. In addition, the respective distal end portions of the support protrusions 74 that penetrate the support holes 61 of the circuit board 43 are inserted into the fixing holes 107 provided in the thin-walled portion 106 of the partial assembly 44. Therefore, the partial assembly 44 is positioned inside the second accommodating chamber 73.

[0079] In the case where the partial assembly 44 is held inside the second accommodating chamber 73 via the two engaging protrusions 104, 105 and the supporting protrusion 74 as described above, thermal compression is applied to the respective distal end portions of the supporting protrusion 74 that penetrate the fixing hole 107 of the partial assembly 44. That is, for example, the supporting protrusion 74 that penetrates the fixing hole 107 of the partial assembly 44 is plastically deformed to be compressed by simultaneously heating and pressurizing the respective distal end portions of the supporting protrusion 74 using a mold heated by a heater. Therefore, the partial assembly 44 is fixed inside the second accommodating chamber 73.

[0080] Then, if Fig. 9 As shown in the figure, the opening portion 73a of the sensor housing 45 is closed with a cover 46. The cover 46 is fixed to the sensor housing 45 by, for example, laser welding. Thereafter, the sensor housing 45 to which the circuit board 43, the partial assembly 44, and the cover 46 are attached is attached to the pinion shaft 13 to which the yoke 42 is attached. However, it should be noted that the sensor housing 45 is fitted with the pinion shaft 13 from the first accommodating chamber 72 side. Therefore, the driven gears 96, 97 gradually move in the direction along the axis O of the pinion shaft 13 to become closer to the main drive gear 54 provided on the yoke 42. As mentioned previously Figure 3 As illustrated in FIG. 1 , the bottom portion 45a of the sensor housing 45 is fitted with the attachment hole 17a of the gear housing 17, and the stepped portion 45b of the sensor housing 45 provided at the peripheral edge portion of the bottom portion 45a abuts against the peripheral edge portion of the attachment hole 17a of the gear housing 17. Further, at this time, the teeth of the driven gears 96, 97 and the teeth of the main drive gear 54 are engaged with each other. The sensor housing 45 is fixed to the gear housing 17 by inserting a bolt into the fastening portion of the sensor housing 45 in this case and fastening the sensor housing 45 to the gear housing 17.

[0081] The assembly of the sensor device 24 is completed as described above.

[0082] Positional relationship between driven gear and main drive gear

[0083] Next, the positional relationship between the driven gears 96 , 97 and the main drive gear 54 in a state where the sensor device 24 is assembled will be described.

[0084] like Fig.10 As shown in FIG. 2 , in the case where the sensor device 24 is assembled, the two driven gears 96, 97 are meshed with the main drive gear 54. Therefore, when the pinion shaft 13 rotates, the main drive gear 54 also rotates together, and accordingly, the two driven gears 96, 97 also rotate. In addition, the respective numbers of teeth of the two driven gears 96, 97 are different from each other. Therefore, in the case where the main drive gear 54 rotates with the rotation of the pinion shaft 13, the respective rotation angles of the two driven gears 96, 97 relative to the rotation angle of the main drive gear 54 are different from each other.

[0085] Positional relationship between driven gear and magnetic sensor

[0086] Next, the positional relationship between the permanent magnets 133 , 136 of the driven gears 96 , 97 and the magnetic sensors 63 , 64 for angle detection in a state where the sensor device 24 is assembled will be described.

[0087] like Figure 3 As shown in FIG. 2 , when the sensor device 24 is assembled, the permanent magnets 133, 136 provided in the driven gears 96, 97 face the magnetic sensors 63, 64 for angle detection provided on the circuit board 43 in the direction along the axis O of the pinion gear 13. The magnetic sensors 63, 64 generate electrical signals that match the changes in the magnetic field accompanying the rotation of the driven gears 96, 97, respectively. The control device 25 detects the rotation angle θpa of the pinion shaft 13 as the steering angle θs based on the electrical signals generated by the magnetic sensors 63, 64.

[0088] Positional relationship between yoke, magnetic collecting ring and core

[0089] Next, the positional relationship between the two yokes 51 , 52 , the two magnetic flux collecting rings 81 , 82 , and the core 92 in a state where the sensor device 24 is assembled will be described.

[0090] like Fig.11As shown in the figure, when the sensor device 24 is assembled, the permanent magnet 41 is positioned inside the two yokes 51, 52. A gap is formed over the entire circumference between the inner peripheral surface of each of the two yokes 51, 52 and the outer peripheral surface of the permanent magnet 41. In addition, the magnetic collecting ring 81 and the magnetic collecting ring 82 are respectively maintained at positions corresponding to the yoke 51 and the yoke 52 in the direction along the axis O of the pinion shaft 13. The magnetic collecting ring 81 surrounds the periphery of the yoke 51. The magnetic collecting ring 82 surrounds the periphery of the yoke 52. Gaps are formed over the entire circumference between the magnetic collecting ring 81 and the yoke 51 and between the magnetic collecting ring 82 and the yoke 52. The magnetic collecting ring 81 induces magnetic flux from the yoke 51. The magnetic collecting ring 82 induces magnetic flux from the yoke 52.

[0091] In addition, when the sensor device 24 is assembled, the core 92 is held at a position corresponding to the magnetic flux collecting ring 82 in the direction along the axis O of the pinion shaft 13. The two arm portions 111a, 111b of the core 92 are held close to the outer peripheral surface of the magnetic flux collecting ring 82. The core 92 induces magnetic flux from the magnetic flux collecting ring 82.

[0092] In addition, a gap δ is formed between the inner surface of the connecting portion 112 of the core 92 and the outer peripheral surface of the magnetic collecting ring 82. Even in the case where the reinforcing member 151 is present between the first accommodating chamber 72 and the second accommodating chamber 73 inside the sensor housing 45, the size of the gap δ can be set according to the size of the reinforcing member 151 so that the partial assembly 44 provided with the core 92 can be installed inside the second accommodating chamber 73 through the opening portion 73a of the sensor housing 45. The core 92 is arranged in a manner that bypasses the reinforcing member 151 so that the two arm portions 111a and 111b of the core 92 can be close to the outer peripheral surface of the magnetic collecting ring 82.

[0093] In addition, the two magnetic collecting protrusions 113a, 113b of the core 92 and the two magnetic collecting protrusions 81a, 81b of the magnetic collecting ring 81 are opposite to each other in the direction along the axis O of the pinion shaft 13. The magnetic sensors 65, 66 for torque detection provided on the circuit board 43 are respectively placed between the magnetic collecting protrusions 113a and the magnetic collecting protrusions 81a and between the magnetic collecting protrusions 113b and the magnetic collecting protrusions 81b. The magnetic sensors 65, 66 detect the magnetic flux induced by the magnetic collecting rings 81, 82 and the core 92.

[0094] When the torsion bar 32 of the pinion shaft 13 is twisted and deformed by the operation of the steering wheel 11, the relative positions of the permanent magnet 41 and the two yokes 51 and 52 in the rotation direction change. Therefore, the magnetic flux density induced from the permanent magnet 41 through the yokes 51 and 52 to the magnetic flux collecting rings 81 and 82 changes. In addition, the magnetic flux density induced from the magnetic flux collecting ring 82 to the core 92 also changes.

[0095] The magnetic sensor 65 generates an electrical signal that matches the magnetic flux leaked between the magnetic collecting protrusion 81a of the magnetic collecting ring 81 and the magnetic collecting protrusion 113a of the core 92. The magnetic sensor 66 generates an electrical signal that matches the magnetic flux leaked between the magnetic collecting protrusion 81b of the magnetic collecting ring 81 and the magnetic collecting protrusion 113b of the core 92. That is, the electrical signals generated by the magnetic sensors 65 and 66 change according to the torsional deformation of the torsion bar 32 and therefore according to the torsion angle of the torsion bar 32. The control device 25 detects the torque acting on the torsion bar 32 as the steering torque based on the electrical signals generated by the magnetic sensors 65 and 66.

[0096] Functions of implementation methods

[0097] Next, the functions of the sensor device 24 constructed as described above will be described. It is necessary that the sensor device 24 should meet various requirements according to product specifications. Examples of items required for the sensor device 24 include environmental requirements, output requirements, and connector directions.

[0098] The environmental requirements are requirements based on the environment in which the sensor device 24 is installed, and the environmental requirements generally include the following two requirements (A1) and (A2). However, it should be noted that examples of the installation environment of the sensor device 24 include conditions such as ambient temperature, humidity, and vibration around the sensor device 24:

[0099] (A1) The sensor device 24 supports a normal installation environment; and

[0100] (A2) The sensor device 24 supports an environment that is more severe than a normal installation environment.

[0101] The output requirements are the detection functions required by the sensor device 24, and the output requirements include the following requirements (B1) to (B3):

[0102] (B1) The sensor device 24 has both torque detection function and angle detection function;

[0103] (B2) The sensor device 24 has only a torque detection function; and

[0104] (B3) The sensor device 24 has only an angle detection function.

[0105] The connector direction is a requirement regarding the extending direction of the connector fitting portion 76 of the sensor housing 45, and the connector direction includes the following requirements (C1) and (C2):

[0106] (C1) the connector fitting portion 76 extends in a first direction along the axis O of the pinion shaft 13; and

[0107] (C2) The connector fitting portion 76 extends along the second direction, which is orthogonal to the axis O of the pinion shaft 13 .

[0108] The sensor device 24 according to the present embodiment satisfies the environmental requirement (A1), the output requirement (B1), and the connector direction requirement (C1).

[0109] As described above, there are various combinations of requirements for the sensor device 24. Therefore, the design of the sensor device 24 may need to be checked according to the requirements, which may increase the product cost or manufacturing cost of the sensor 24. In addition, it is also necessary to prepare various variations of the components of the sensor device 24 according to the product specifications.

[0110] For example, in the case where the sensor device 24 is to support an environment that is more severe than the normal installation environment, it is conceivable that the sensor device 24 adopts the following configuration. That is, the sensor housing 45 is formed of aluminum, and the core components made of synthetic resin and required to exhibit the detection function required by the sensor device 24 are designed separately from the sensor housing 45, and such core components are installed in the sensor housing 45 made of aluminum. In contrast, in the case where the sensor device 24 is to support a normal installation environment, it is conceivable that the sensor housing 45 is formed of a synthetic resin material and some core components made of synthetic resin are integrally provided with the sensor housing 45. As described above, the sensor device 24 can be configured differently depending on the environment in which the sensor device 24 is installed.

[0111] In this regard, in the sensor device 24 according to the present embodiment, a core component required to exhibit the detection function required by the sensor device 24 is provided as a partial assembly 44, and the partial assembly 44 is attached to the sensor housing 45. The core component includes a retaining member 91, a core 92, magnetic shielding members 93, 94, a torsion coil spring 95, driven gears 96, 97, and a gear stopper 98.

[0112] Therefore, the output requirement of the sensor device 24 can be supported, for example, in the following manner. In the case where the aforementioned requirement (B2) needs to be satisfied, that is, in the case where the sensor device 24 is required to have only a torque detection function, for example, only the retaining member 91, the core 92, and the gear stopper 98 are assembled as a partial assembly 44. However, it should be noted that the core 92 is molded integrally with the retaining member 91 by resin molding. In this case, the magnetic shields 93, 94, the torsion coil spring 95, and the driven gears 96, 97 are not used.

[0113] In the case where the aforementioned requirement (B3) needs to be satisfied, that is, in the case where the sensor device 24 is required to have only the angle detection function, at the same time, only the retaining member 91, the magnetic shielding members 93, 94, the torsion coil spring 95, the driven gears 96, 97 and the gear stopper 98 are assembled as the partial assembly 44. In this case, the core 92 is not used.

[0114] As described above, regardless of the output requirements of the sensor device 24, these same components can be used as core components by selectively changing the core components to be assembled into the partial assembly 44 of the sensor device 24 according to the output requirements for the sensor device 24. In addition, the environmental requirements and connector direction requirements of the sensor device 24 can also be supported by only changing the material or shape of the sensor housing 45 according to these requirements.

[0115] However, it should be noted that the specification of the attachment portion between the sensor housing 45 and the partial assembly 44 is preferably standardized regardless of the material or shape of the sensor housing 45. As described above, the partial assembly 45 can be attached to the sensor housing 45 in the case where the core components are rearranged or the shape or material of the sensor housing 45 is changed. The phrase "specification of the attachment portion between the sensor housing 45 and the partial assembly 44" refers to the configuration of the engagement between the U-shaped engagement protrusions 104, 105 of the retainer 91 and the engagement protrusions 152, 153 that constitute a part of the sensor housing 45.

[0116] Effects of implementation methods

[0117] Therefore, the following effects can be obtained by using the present embodiment. The retaining member 91, the core 92, the magnetic shielding members 93, 94, the torsion coil spring 95, the driven gears 96, 97 and the gear stopper 98 are prepared as core components required to exhibit the detection function of the sensor device 24, and the core components assembled into the partial assembly 44 are selectively changed according to the detection function required by the sensor device 24. Therefore, regardless of the detection function required by the sensor device, these same components can be used as core components. Therefore, the increase in the number of variations of the constituent components of the partial assembly 44 can be suppressed, and thus the increase in the number of variations of the constituent components of the sensor device 24 can be suppressed. In addition, the development cost or design cost of the sensor device 24 can be reduced according to the amount corresponding to the common amount of the constituent components of the partial assembly 44.

[0118] For environmental requirements and connector orientation requirements, only the material or shape of the sensor housing 45 needs to be changed. No changes are required to the partial components 44 accommodated inside the sensor housing 45. Therefore, changes in the material or shape of the sensor housing 45 can be flexibly and inexpensively supported.

[0119] When attaching the partial assembly 44 to the sensor housing 45, the engaging protrusions 104, 105 of the partial assembly 44 having a U-shaped plate shape are respectively engaged with the two engaging protrusions 152, 153 provided inside the second accommodating chamber 73. Therefore, the partial assembly 44 is suppressed from falling from the second accommodating chamber 73. In addition, the partial assembly 44 can be easily installed by being inserted into the second accommodating chamber 73.

[0120] After the partial assembly 44 is attached to the inside of the second accommodating chamber 73 via the opening portion 73a of the sensor housing 45, the opening portion 73a is closed by the cover 46. Therefore, dust or liquid is suppressed from entering the sensor housing 45. In addition, the second accommodating chamber 73 is tightly closed by the cover 46, so it is not necessary to provide a liquid sealing function for the partial assembly 44. Therefore, it is possible to suppress the complication of the configuration of the partial assembly 44 or the increase in the number of parts of the partial assembly 44.

[0121] In addition, the partial assembly 44 does not have a function as the sensor housing 45. Therefore, unlike the case where the holder 91 of the partial assembly 44 constitutes a part of the sensor housing 45, for example, an increase in the number of variations of the holder 91 can be suppressed.

[0122] The circuit board 43 and the partial assembly 44 are arranged inside the second accommodating chamber 73 in a state of being stacked on each other in the direction along the axis O of the pinion shaft 13. Therefore, unlike the case where the circuit board 43 and the partial assembly 44 are arranged, for example, on the same plane, an increase in the size of the sensor housing 45 in the direction orthogonal to the axis O of the pinion shaft 13 is suppressed.

[0123] The reinforcing member 151 is disposed inside the second accommodating chamber 73 opened via the opening portion 73a. Therefore, the rigidity of the sensor housing 45 can be ensured while ensuring the opening area of ​​the opening portion 73a. When the opening area of ​​the opening portion 73a is larger, the operation of the circuit board 43 and the partial components 44 to the second accommodating chamber 73 is easier.

[0124] The sensor device 24 detects the rotation angle of the main drive gear 54 based on the respective rotation angles of the two driven gears 96, 97 meshing with the main drive gear 54. Therefore, the looseness caused by the side clearance at the two gaps, namely the gap between the main drive gear 54 and the driven gear 96 and the gap between the main drive gear 54 and the driven gear 97, affects the accuracy in calculating the rotation angle of the main drive gear 54, especially in the case where the main drive gear 54 starts the rotation operation or in the case where the rotation direction of the main drive gear 54 is reversed. In this regard, with the present embodiment, when the sensor device 24 is fully assembled, the driven gears 96, 97 are maintained in a state where they are pushed against the main drive gear 54 by the elastic force of the torsion coil spring 95. Therefore, the clearance between the teeth of the driven gears 96, 97 and the teeth of the main drive gear 54 can be reduced. In addition, the accuracy in calculating the rotation angle of the main drive gear 54 is improved according to the amount of looseness caused by the side clearance that is suppressed.

[0125] The two support holes 101, 102 of the holder 91 are long holes extending in the radial direction of the main drive gear 54. Therefore, for example, when the sensor device 24 is assembled, in the case where an external force in the direction along the extension of the support holes 101, 102 acts on the driven gears 96, 97 in a direction away from the main drive gear 54, the driven gears 96, 97 can overcome the elastic force of the torsion coil spring 95 and move in a direction away from the main drive gear 54. Therefore, the driven gears 96, 97 supported by the holder 91 are protected.

[0126] Other Implementations

[0127] The present embodiment may be modified as follows. The two bearing holes 101, 102 provided in the retainer 91 may not be elongated holes but circular holes having inner diameters matching the outer diameters of the shaft portions 132, 135 of the driven gears 96, 97, respectively. With this configuration, effects similar to those of the above-described embodiment may be obtained.

[0128] Although the magnetic shields 93, 94 are provided on the holder 91 in the present embodiment, the magnetic shields 93, 94 may be provided on the shaft portions 132, 135 of the driven gears 96, 97, respectively. The torsion coil spring 95 may be omitted from the partial assembly 44. The magnetic shields 93, 94 may be omitted from the partial assembly 44.

[0129] The gear stopper 98 may be omitted from the partial assembly 44. In this case, the driven gears 96, 97 may be retained on the holder 91 by a different retaining means other than the gear stopper 98. For example, the holder 91 may be provided with a portion for retaining the driven gears 96, 97, or a retaining ring may be mounted to the respective distal end portions of the shaft portions 132, 135 of the driven gears 96, 97. With this configuration, the driven gears 96, 97 may be suppressed from falling off the holder 91.

[0130] Although in the present embodiment, the magnetic collecting ring 81 is provided with two magnetic collecting protrusions 81a, 81b, and the core 92 is provided with two magnetic collecting protrusions 113a, 113b, the magnetic collecting ring 81 and the core 92 may each be provided with one magnetic collecting protrusion. In this case, it is only necessary to place one magnetic sensor (65 or 66) between one magnetic collecting protrusion of the magnetic collecting ring 81 and one magnetic collecting protrusion of the core 92.

[0131] Although in the present embodiment, the main drive gear 54 is formed integrally with the holder 53 of the yoke 42, the main drive gear 54 and the yoke 42 may be provided as separate parts. In the case of adopting this configuration, for example, when it is necessary to satisfy the aforementioned requirement (B2), that is, when the sensor device 24 is required to have only a torque detection function, the pinion shaft 13 may be provided with only the yoke 42 as a separate part, and the main drive gear 54 may be omitted from the pinion shaft 13. At the same time, when it is necessary to satisfy the aforementioned requirement (B3), that is, when the sensor device 24 is required to have only an angle detection function, the pinion shaft 13 may be provided with only the main drive gear 54 as a separate part.

[0132] Although in the present embodiment, two driven gears 96, 97 meshing with the main drive gear 54 are provided as components for detecting the rotation angle θpa of the pinion shaft 13, the sensor device 24 may be configured to have a single driven gear 96 or a driven gear 97. Also in this manner, the rotation angle θpa within 360° of the pinion shaft 13 can be detected. Alternatively, the sensor device 24 may be configured to have three or more driven gears. With this configuration, the rotation angle θpa of the pinion shaft 13 for multiple rotations exceeding 360° can be detected.

[0133] Although the sensor device 24 is applied to an electric power steering system (EPS) as an example of a steering device of a vehicle in the present embodiment, the sensor device 24 can also be applied to a steer-by-wire system. In addition, the sensor device 24 is not limited to being used in a vehicle.

Claims

1. A sensor device (24), characterized in that include: A partial assembly (44) formed by mounting a component as at least one of a magnetism collecting member (92) configured to induce a magnetic flux matching the torsion of a shaft (13) as a detection target and a driven wheel (96, 97) to a holder (91), the magnetism collecting member (92) configured to induce a magnetic flux matching the torsion of a shaft (13) as a detection target, and the driven wheel (96, 97) configured to rotate with the rotation of the shaft (13); a circuit board (43), the circuit board (43) being provided with detectors (63, 64), the detectors (63, 64) being configured to detect at least one of a magnetic flux induced by the magnetic collecting member (92) and a rotation angle of the driven wheels (96, 97) according to the component mounted to the holder (91); as well as a sensor housing (45), wherein the shaft (13) penetrates through the sensor housing (45) and the sensor housing (45) accommodates the partial assembly (44) and the circuit board (43), The subassembly (44) includes a retaining member (98) which retains the driven wheels (96, 97) on the retaining member (91). The sensor housing (45) includes a cover (46) that closes an opening portion that is open in a direction that intersects the axis of the shaft (13), and the sensor housing (45) includes a housing chamber that houses the partial components and the circuit board via the opening portion.

2. The sensor device (24) according to claim 1, characterized in that The retainer (91) includes engaging portions (104, 105), and the partial assembly (44) is retained inside the sensor housing (45) when the engaging portions (104, 105) are engaged with a portion of the sensor housing (45).

3. The sensor device (24) according to claim 1 or 2, characterized in that The retaining member (98) is mounted to the retaining member (91) to cover the driven wheels (96, 97).

4. The sensor device (24) according to claim 1 or 2, characterized in that The shaft (13) rotates in response to the operation of the steering wheel.

Images