JP4833635B2 - Torque sensor and electric power steering device - Google Patents

Description

  The present invention relates to a torque sensor and an electric power steering apparatus.

  In the electric power steering apparatus, an input shaft to which a steering wheel is coupled and an output shaft are connected via a torsion bar, and a steering torque applied to the steering wheel is detected by a torque sensor, and the electric motor is driven by the detected torque. The generated torque of the electric motor is transmitted to the output shaft side, and as a result, the generated torque of the electric motor is used as an assist force for the steering force applied to the steering wheel by the driver.

  As described in Patent Document 1, a conventional torque sensor supports an input shaft and an output shaft rotatably on a housing via an input bearing and an output bearing, and is fixed to each of the input shaft and the output shaft. A torque detection coil that constitutes a magnetic circuit together with the first and second cores is provided in the housing to detect the torque acting on the torsion bar connecting the input shaft and the output shaft.

Moreover, in the torque sensor of patent document 1, the temperature compensation coil which comprises a magnetic circuit with the outer peripheral cylindrical part of the input shaft which consists of magnetic materials is provided in a housing, and the difference of the induced voltage of a torque detection coil and a temperature compensation coil is calculated | required. In addition, the induced voltage phase due to the ambient temperature change is offset and the detection accuracy of the torque sensor is improved.
JP2005-3462

  In the torque sensor of Patent Document 1, an input bearing is provided near the temperature compensation coil in the housing axial direction, and the temperature compensation coil is electromagnetically coupled to the outer peripheral cylindrical portion of the input shaft, and has the following problems.

  (1) An input bearing is provided directly above the temperature compensation coil, and it is necessary to consider magnetic shielding so that the input bearing does not interfere magnetically with the magnetic circuit of the temperature compensation coil to deteriorate the magnetic characteristics. .

  (2) Since the input bearing is positioned on the opposite side of the output bearing across the temperature compensation coil in the axial direction of the input shaft and the output shaft, the support span of the input bearing and the output bearing is large. For this reason, it is difficult to improve the concentricity of the input shaft and the output shaft, and the rotational eccentricity of the both increases, which may impair the torque detection accuracy.

  Moreover, in the torque sensor of Patent Document 1, the input bearing that supports the input shaft and the temperature compensation coil are separately mounted on the housing, and the axial dimension of the housing increases, resulting in a large number of parts and a large number of assembly steps.

  An object of the present invention is to provide a torque sensor with a compact housing, reduce the number of parts and assembly steps, reduce costs, stabilize the magnetic characteristics of the temperature compensation coil, and improve detection accuracy (sensitivity). It is in.

  According to a first aspect of the present invention, there is provided an input bearing for supporting an input shaft in a torque sensor in which an input shaft and an output shaft accommodated in a housing are connected via a torsion bar and a torque detection coil and a temperature compensation coil are provided in the housing. Is insert-molded into a resin-made temperature compensation coil bobbin, and the temperature compensation coil is electromagnetically coupled to the input bearing.

  According to a second aspect of the present invention, in addition to the first aspect of the present invention, the temperature compensation coil bobbin is integrally molded with a torque detection coil bobbin.

According to a third aspect of the present invention , the temperature compensation coil bobbin and the torque detection coil bobbin, which are integrally molded with the resin in the second aspect of the invention, and the torque detection coil and the temperature compensation wound around the bobbin, respectively. The coil is insert-molded into a resin yoke mixed with magnetic metal powder.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the yoke is insert-molded in a resin housing.

  The invention according to claim 5 has an input shaft to which the steering wheel is coupled, and an output shaft linked to the electric motor side, and the electric motor is detected by a torque signal detected by the torque sensor according to any one of claims 1 to 4. It is an electric power steering device characterized by driving.

(Claim 1)
(a) Since the input bearing supporting the input shaft is insert-molded on the bobbin of the temperature compensation coil and the temperature compensation coil is electromagnetically coupled to the input bearing, the input bearing directly constitutes the magnetic circuit of the temperature compensation coil. There is no need to consider interference of the input bearing with the magnetic circuit. Therefore, the magnetic characteristics can be easily stabilized without providing a magnetic shielding member for the temperature compensation coil.

  (b) The input bearing is not located on the opposite side of the output bearing across the temperature compensation coil in the axial direction of the input shaft and the output shaft, but is disposed at substantially the same position in the axial direction as the temperature compensation coil. The support span between the input bearing and the output bearing can be shortened. For this reason, the coaxiality of the input shaft and the output shaft is improved, and the torque eccentricity can be suppressed by suppressing the rotational eccentricity of both.

  (c) Since the input bearing is integrated with the bobbin of the temperature compensation coil, the number of parts and assembly steps can be reduced, and the cost can be reduced. In addition, the input shaft can be supported stably.

(Claim 2)
(d) When the torque detection coil and the temperature compensation coil are provided in the housing, the torque detection coil bobbin and the temperature compensation coil bobbin are molded into a single bobbin and integrated into a single unit. Assembling property and assembling dimensional error can be eliminated and cost can be reduced.

(Claim 3)
(e) Since the above-described bobbin (d), the torque detection coil and the temperature compensation coil wound around the bobbin are insert-molded in a resin yoke mixed with magnetic metal powder, the number of torque sensor components and assembly man-hours In addition, the air gap formed by the yoke between the bobbin and the coil can be reduced as much as possible to improve the detection accuracy of the torque sensor.

(Claim 4)
(f) Since the yoke described in (e) above is insert-molded in the resin housing, the number of torque sensor components and assembly man-hours can be further reduced.

(Claim 5)
(g) In the torque sensor of the electric power steering apparatus, the above (a) to (f) can be realized. Thereby, the detection accuracy of the steering torque applied to the steering wheel can be improved, and the assist performance by the electric motor can be improved.

  1 is a cross-sectional view showing the main part of the electric power steering apparatus, FIG. 2 is an enlarged cross-sectional view showing a torque sensor, FIG. 3 is a cross-sectional view showing an insert-molded body of a bobbin to a yoke, and FIG. Sectional drawing which expands and shows the core and the 2nd core, FIG. 5 is a schematic diagram of a torque sensor.

  As shown in FIG. 1, the electric power steering apparatus 10 bolts a second housing 12 to a first housing 11 fixed to a vehicle body frame or the like. The input shaft 14 to which the steering wheel is coupled and the output shaft 15 are coaxially coupled via a torsion bar 16. The input shaft 14 is supported by the second housing 12 via an input bearing 17, and the output shaft 15 is an output. It supports to the 1st housing 11 side via the bearing 18 (not shown).

  The electric power steering device 10 connects a pinion shaft to the output shaft 15 and supports a rack shaft including a rack that meshes with the pinion of the pinion shaft so that the rack shaft can move left and right. The rotary motion of the output shaft 15 is converted into the linear motion of the rack shaft via the pinion shaft, and the wheels are steered.

  The electric power steering device 10 supports an electric motor (not shown) on a first housing 11, a worm gear 21 is coupled to an output shaft of the electric motor, and a worm wheel 22 meshing with the worm gear 21 is connected to the first housing 11 and the second housing 11. The housing 12 is fixed to the output shaft 15.

  The electric power steering apparatus 10 is provided with a torque sensor 30 between the input shaft 14 and the output shaft 15. The steering torque applied to the steering wheel is detected by the torque sensor 30, the electric motor is driven by the detected torque, and the generated torque of the electric motor is transmitted to the output shaft 15 via the worm gear 21 and the worm wheel 22. Thereby, the torque generated by the electric motor is used as an assist force for the steering force applied by the driver to the steering wheel.

However, the torque sensor 30 is configured as follows (FIG. 2).
The input shaft 14 is made of a magnetic material and is coaxially fixed by press-fitting a large-diameter collar A made of a magnetic material on the side of a portion located inside the housing 12 and coaxially coupled to the output shaft 15. Installed on. The first core 40 is coaxially fixed to the large-diameter collar A by press-fitting or the like, and a plurality of rectangular magnetic path forming portions having a rectangular shape in plan view formed at equal pitches in the circumferential direction on the lower end surface of the first core 40 40A is provided.

  The output shaft 15 has a cylindrical second core 50 attached to the outer periphery of a portion located inside the housing 12 and coaxially coupled to the input shaft 14 in a press-fit manner. On the end surface of the upper end portion of the second core 50, a large number of magnetic path forming portions 50 </ b> A having a rectangular shape in plan view and formed at an equal pitch in the circumferential direction facing the magnetic path forming portions 40 </ b> A of the first core 40 are provided.

  A bobbin 80 around which the torque detection coil 60 and the temperature compensation coil 70 are wound and a yoke 90 that encloses the bobbin 80 are loaded on the inner periphery of the housing 12 as follows (FIGS. 2 and 3).

  (1) A bobbin for the torque detection coil 60 and a bobbin for the temperature compensation coil 70 are integrally formed of synthetic resin to constitute a bobbin 80.

  At this time, with the input bearing 17 that supports the input shaft 14 incorporated in the mold, a bobbin 80 made of synthetic resin is injection-molded on the outer peripheral side of the input bearing 17, and the input bearing 17 is made into the bobbin 80, particularly the bobbin. Insert molding is performed on the inner peripheral portion of the coil winding portion 82 for the temperature compensation coil 70 at 80. As a result, the temperature compensation coil 70 is electromagnetically coupled to the input bearing 17 as will be described later. The bobbin 80 is a flange-shaped bearing inner end locking projecting radially inward toward the lower end side of the inner peripheral part of the coil winding part 82 (close to the inner peripheral part of the coil winding part 82 in the axial direction of the bobbin 80). 80A is provided, and the bearing inner end locking portion 80A is brought into close contact with the inner end surface of the outer ring 17A of the input bearing 17. Alternatively, the bobbin 80 may be separately molded, and the input bearing 17 may be inserted into the bearing inner end locking portion 80A of the bobbin 80 and positioned.

  (2) Each of the torque detection coil 60 and the temperature compensation coil 70 is wound around the coil winding portion 81 and the coil winding portion 82 provided respectively at the upper and lower portions of the outer periphery of the bobbin 80 described in (1) above. To do.

  (3) Synthetic resin in which the magnetic metal powder such as iron powder is mixed with the bobbin 80 of the above (2), the torque detection coil 60 and the temperature compensation coil 70 wound around the bobbin 80 incorporated in the mold. The yoke 90 is formed by injection molding on the outer periphery side of the bobbin 80, the torque detection coil 60, and the temperature compensation coil 70, and the bobbin 80, the torque detection coil 60, and the temperature compensation coil 70 are insert-molded by the yoke 90.

  (4) With the yoke 90 of (3) described above incorporated in the mold, the housing 12 made of synthetic resin is injection-molded on the outer periphery side of the yoke 90 and insert molded with the housing 90 together with the yoke 90. The housing 12 wraps around from the upper end of the yoke 90 to the inner periphery of the yoke 90 and the inner periphery of the bobbin 80, and the wrap-around ends serve as bearing outer end locking portions 90A. The bearing outer end locking portion 90A is brought into close contact with the outer end surface of the outer ring 17A. At the same time, the housing 12 turns from the lower end portion of the yoke 90 to the lower end surface of the yoke 90, and the wraparound end serves as the yoke lower end locking portion 90 </ b> B.

  The first housing 11 is bolted to the second housing 12 described in (4) above, the input shaft 14 is supported by the input bearing 17 of the second housing 12, and the output shaft 15 is supported by the output bearing 18 of the first housing 11. In this state, the torque detection coil 60 straddles the opposing portions of the first core 40 and the second core 50 attached to the large-diameter collar A of the input shaft 14 and the output shaft 15, respectively. The yoke 90 constitutes the first core 40 and the second core 50 and the magnetic circuit a. The magnetic circuit a is an air gap a 1 between the yoke 90 and the surface of the first core 40, and the surface of the second core 50. And an air gap a3 between the opposing end surfaces of the first core 40 and the second core 50. The torque detection coil 60 is electromagnetically coupled to the first core 40 and the second core 50 and induces a voltage corresponding to the electromagnetic coupling state.

  Here, the torque sensor 30 is provided with the above-described input bearing 17 made of a magnetic material between the bobbin 80 (coil winding portion 82) around which the temperature compensation coil 70 is wound and the input shaft 14. In the input bearing 17, the outer ring 17 </ b> A is insert-molded on the inner peripheral portion of the coil winding portion 82 of the bobbin 80 without a gap, the inner ring 17 </ b> B is fitted on the outer periphery of the input shaft 14, and the input shaft 14 is rotatably supported. The temperature compensation coil 70 constitutes an input bearing 17 (outer ring 17A) and a magnetic circuit b. The magnetic circuit b is formed so as to pass through air gaps b1 and b2 between the yoke 90 and the surface of the input bearing 17 (outer ring 17A). The The temperature compensation coil 70 is electromagnetically coupled to the input bearing 17 (outer ring 17A) and induces a voltage corresponding to the electromagnetic coupling state for temperature compensation.

  When no torque is applied to the torsion bar 16, the electromagnetic waves of the first core 40, the second core 50, and the input bearing 17 are set so that the induced voltages of the torque detection coil 60 and the temperature compensation coil 70 are substantially equal. The coupling state is obtained, and the first core 40 and the second core 50 are positioned. The outer diameter of the input bearing 17 depends on the influence of the air gaps b1, b2 in the magnetic circuit b on the magnetic field, that is, the sum of the respective magnetic resistances gb1, gb2 is the air gaps a1, a2, a3 in the magnetic circuit a. Are set to be equal to the influence of the magnetic resistances on the magnetic field, that is, the sum of the respective magnetic resistances ga1, ga2, and ga3.

  Therefore, in the torque sensor 30, the difference between the induced voltages of the torque detection coil 60 and the temperature compensation coil 70 is obtained to cancel the induced voltage due to the ambient temperature change, and the first core 40 and the second core 50. The electromagnetic coupling state corresponding to the relative rotation amount is detected, and only the torque acting on the torsion bar 16, in other words, the steering torque applied to the steering wheel can be detected.

Hereinafter, the configuration of the first core 40 and the second core 50 will be described (FIG. 4).
The first core 40 has a shielding material 42 made of a non-magnetic material such as stainless steel, aluminum, copper, resin, etc. set in a mold, and a magnetic metal powder such as iron powder or the like around the shielding material 42. The magnetic material 41 mixed with is cast and insert molded. Specifically, the shielding material 42 has a cylindrical shape (cylindrical body 42A), teeth 42B are provided at a plurality of positions in the circumferential direction of the lower end, and the magnetic material 41 is molded in a valley 42C between adjacent teeth 42B. . The magnetic material 41 includes a cylindrical main body 41A molded on the inner periphery of the cylindrical main body 42A of the shielding material 42, and a loading portion that protrudes radially outward in a L shape from a plurality of circumferential positions at the lower end of the cylindrical main body 41A. 41B is formed, and the rectangular end surface in plan view, which is the downward end surface of the loading portion 41B, is formed in a plane perpendicular to the central axis of the input shaft 14 by matching the downward end surface itself of the crest of the tooth 42B.

  The first core 40 uses the teeth 42 </ b> B of the shielding material 42 as a magnetic shielding part 40 </ b> B for the magnetic material 41. The first core 40 is magnetized on the side of the portion shielded by the shielding portion 40B (teeth 42B) of the shielding material 42 in the circumferential direction of the lower end surface (rectangular portion in plan view sandwiched between the adjacent shielding portions 40B and 40B). The non-shielding portion (loading portion 41B) of the material 41 is matched with the downward end surface of the crest of the tooth 42B, and this non-shielding portion is used as the above-described magnetic path forming portion 40A.

  At this time, the first core 40 molds the magnetic material 41 from the lower end portion to the intermediate portion of the cylindrical main body 42A of the shielding material 42 and does not mold it from the intermediate portion to the upper end portion. The first core 40 press-fits the cylindrical body 42 </ b> A of the shielding material 42 into the large-diameter collar A of the input shaft 14.

  In the second core 50, a shielding material 52 made of a nonmagnetic material such as stainless steel, aluminum, copper, or resin is set in a mold. Around the shielding material 52, a magnetic material metal powder such as iron powder is applied to the resin. The magnetic material 51 mixed with is cast and insert molded. Specifically, the shielding material 52 has a cylindrical shape (cylindrical main body 52A), teeth 52B are provided at a plurality of positions in the circumferential direction of the upper end portion, and the magnetic material 51 is molded in the valley portions 52C between the adjacent teeth 52B. . The magnetic material 51 includes a cylindrical main body 51A molded on the inner periphery of the cylindrical main body 52A of the shielding material 52, and a loading portion that protrudes radially outward in an L shape from a plurality of circumferential positions at the upper end of the cylindrical main body 51A. 51B is formed, and the rectangular end surface in plan view, which is the upward end surface of the loading portion 51B, is formed in a plane perpendicular to the central axis of the output shaft 15 by matching the upward end surface of the tooth 52B.

  The second core 50 uses the teeth 52 </ b> B of the shielding material 52 as a magnetic shielding part 50 </ b> B for the magnetic material 51. The second core 50 is magnetic on the side of the portion shielded by the shielding portion 50B (teeth 52B) of the shielding material 52 in the circumferential direction of the upper end surface (rectangular portion in plan view sandwiched between adjacent shielding portions 50B and 50B). The non-shielding part (loading part 51B) of the material 51 is matched with the upward end surface itself of the crest of the tooth 52B, and this non-shielding part is used as the magnetic path forming part 50A.

  At this time, the second core 50 molds the magnetic material 51 on the upper end portion to the intermediate portion of the cylindrical main body 52A of the shielding material 52 and does not mold it on the intermediate portion to the lower end portion. The second core 50 press-fits the cylindrical body 52 </ b> A of the shielding material 52 into the output shaft 15.

  The magnetic path forming part 40A of the first core 40 and the magnetic path forming part 50A of the second core 50 have a facing relationship that is appropriately spaced apart. In the present embodiment, the first core 40 (magnetic material 41, shielding material 42) and the second core 50 (magnetic material 51, shielding material 52) have the same shape with the same inner and outer diameter dimensions and axial length dimensions. ing.

According to the present embodiment, the following operational effects can be obtained.
(a) Since the input bearing 17 supporting the input shaft 14 is insert-molded on the bobbin 80 of the temperature compensation coil 70 and the temperature compensation coil 70 is electromagnetically coupled to the input bearing 17, the input bearing 17 is a magnetic circuit of the temperature compensation coil 70. Therefore, it is not necessary to consider interference of the input bearing 17 with the magnetic circuit. Accordingly, the magnetic characteristics of the temperature compensation coil 70 can be easily stabilized.

  (b) The input bearing 17 is not located on the opposite side of the output bearing 18 across the temperature compensation coil 70 in the axial direction of the input shaft 14 and the output shaft 15 but is located at the same position as the temperature compensation coil 70. Therefore, the support span between the input bearing 17 and the output bearing 18 can be reduced. For this reason, the coaxiality of the input shaft 14 and the output shaft 15 is improved, and the rotational eccentricity of both is suppressed, and the torque detection accuracy can be improved.

  (c) Since the input bearing 17 is integrated with the bobbin 80 of the temperature compensation coil 70, the number of parts and the number of assembling steps can be reduced, and the cost can be reduced. Further, the input shaft 14 can be stably supported.

  (d) When the torque detection coil 60 and the temperature compensation coil 70 are provided in the housing 12, the bobbin 80 for the torque detection coil 60 and the bobbin 80 for the temperature compensation coil 70 are resin-molded into a single bobbin 80 and unified. Therefore, the number of parts of the torque sensor 30 and the number of assembling steps can be reduced, thereby reducing the cost.

  (e) Since the bobbin 80 of the above (d) and the torque detection coil 60 and the temperature compensation coil 70 wound around the bobbin 80 are insert-molded by the resin yoke 90 mixed with magnetic metal powder, the torque sensor 30 In addition to reducing the number of parts and the number of assembly steps, the air gap formed between the bobbin 80 and the coil by the yoke 90 is reduced as much as possible, and the detection accuracy of the torque sensor 30 is improved.

  (f) Since the yoke 90 of the above (e) is insert-molded with the resin housing 12, the number of parts and the number of assembling steps of the torque sensor 30 can be further reduced.

  (g) In the torque sensor 30 of the electric power steering apparatus 10, the above-described (a) to (f) can be realized. Thereby, the detection accuracy of the steering torque applied to the steering wheel can be improved, and the assist performance by the electric motor can be improved.

In addition, according to a present Example, there exist the following effects.
(a) The shielding members 42 and 52 made of a non-magnetic material are provided on the end surfaces of the first and second cores 40 and 50, and the non-shielding portion of the magnetic material beside the shielding portions 40B and 50B of the shielding materials 42 and 52. Were defined as magnetic path forming portions 40A and 50A. The path of the magnetic flux generated between the magnetic path forming portion 40A of the first core 40 and the magnetic path forming portion 50A of the second core 50 is the first core 40 as shown by the solid line arrow in FIG. The adjacent shield member 42 has a shield part 40B and a magnetic path forming part 40A in the range sandwiched between the shield parts 40B, and the second core 50 has a shield part 52B and the shield part 50B and the shield part 50B. It is limited to the magnetic path forming portion 50A, and it is possible to suppress the shield portions 40B and 50B from going around as shown by the broken line arrows in FIG. For this reason, the overlapping area of the magnetic path forming portion 40A of the first core 40 and the magnetic path forming portion 50A of the second core 50 accompanying the twist of the torsion bar 16 between the input shaft 14 and the output shaft 15 ( The amount of change in the magnetic permeability according to only the change in the magnetic flux passage area) can be increased, the detection output width of the torque detection coil 60 can be increased, and the detection accuracy and sensitivity can be improved.

  (b) The cores 40 and 50 are formed by insert-molding the shielding materials 42 and 52 made of a non-magnetic material with the magnetic materials 41 and 51 in which the magnetic material metal powder is mixed with the resin. The air gap between the shielding members 42 and 52 can be eliminated, and the detection sensitivity of the torque sensor 30 can be improved.

  (c) The cores 40 and 50 do not require management of dimensional tolerances for assembling both the magnetic members 41 and 51 and the shielding members 42 and 52, and improve the assemblability.

  (d) The magnetic materials 41 and 51 are formed simply by molding a mixture of magnetic material metal powder in a resin around the shielding materials 42 and 52 set in a mold, thereby reducing the cost.

  (e) The shielding material 42 of the first core 40 is press-fitted to the input shaft side, and the shielding material 52 of the second core 50 is press-fitted to the output shaft side. Adhesiveness can be simplified.

  (f) The cores 40 and 50 are assembled by molding the magnetic materials 41 and 51 in the valley portions 42C and 52C between the adjacent teeth 42B and 52B of the shielding materials 42 and 52 set in the mold. Can be improved.

  (g) Since each of the cores 40 and 50 is formed by molding the magnetic materials 41 and 51 into the outer periphery of the cylindrical main bodies 42A and 52A and the valley portions 42C and 52C of the shielding materials 42 and 52, the magnetic materials 41 and 51 The coupling strength of the shielding materials 42 and 52 can be enhanced in the axial direction and the circumferential direction.

  (h) The cores 40 and 50 are set in the mold because the magnetic materials 41 and 51 are molded only at one end to the middle portion of the cylindrical body of the shielding materials 42 and 52 and not from the middle to the other end. The heat shielding performance of the formed shielding materials 42 and 52 at the time of insert molding is improved at the intermediate portion to the other end portion, and as a result, the thermal strain at this portion of the shielding materials 42 and 52 is minimized, and the input shaft or the output shaft The press-fitting dimensional accuracy into the core is improved, and the assemblability of the cores 40 and 50 is improved.

  (i) Since the cores 40 and 50 have the same shape, the cores 40 and 50 can be made into common parts.

  (j) In the torque sensor 30 of the electric power steering apparatus 10, the above (a) to (i) can be realized. Thereby, the detection accuracy of the steering torque applied to the steering wheel can be improved, and the assist performance by the electric motor can be improved.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the present invention. It is included in the present invention. For example, in the present invention, the temperature compensation coil bobbin and the torque detection coil bobbin may be separate.

FIG. 1 is a cross-sectional view showing a main part of the electric power steering apparatus. FIG. 2 is an enlarged sectional view showing the torque sensor. FIG. 3 is a cross-sectional view showing an insert molding of a bobbin to a yoke. FIG. 4 is an enlarged cross-sectional view of the first core and the second core. FIG. 5 is a schematic diagram of a torque sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electric power steering apparatus 11, 12 Housing 14 Input shaft 15 Output shaft 16 Torsion bar 17 Input bearing 30 Torque sensor 60 Torque detection coil 70 Temperature compensation coil 80 Bobbin 90 Yoke

Claims (5)

The input shaft and output shaft housed in the housing are connected via a torsion bar,
In a torque sensor in which a torque detection coil and a temperature compensation coil are provided in a housing,
The input bearing that supports the input shaft is insert molded into a resin temperature compensation coil bobbin,
A torque sensor, wherein a temperature compensation coil is electromagnetically coupled to the input bearing.   The torque sensor according to claim 1, wherein a torque detection coil bobbin is integrally molded with the temperature compensation coil bobbin. The temperature compensation coil bobbin and the torque detection coil bobbin formed integrally with the resin, and the torque detection coil and the temperature compensation coil wound around the bobbin, respectively, are insert-molded into a resin yoke mixed with magnetic metal powder. The torque sensor according to claim 2.   The torque sensor according to claim 3, wherein the yoke is insert-molded in a resin housing.   An input shaft to which a steering wheel is coupled and an output shaft interlocked with the electric motor are provided, and the electric motor is driven and controlled by a torque signal detected by the torque sensor according to any one of claims 1 to 4. Electric power steering device.

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