JP2004333509A - Torque sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the torque detection precision in a torque sensor. <P>SOLUTION: This sensor is provided with the first coil holder 31 inserted in the housing 2 and the second coil holder 32, as component materials of magnetic circuit. The spacer 51 is arranged between both coil holders 31, 32. The torque is detected on the basis of the change in the magneto-resistance in the magnetic circuit. The spacer 51 is molded from insulative material, made of polyphenylene sulfide as substrate fill with fiberglass. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a torque sensor suitable for detecting a steering torque in, for example, a power steering device that applies a steering assist force according to the steering torque.

As a component of the magnetic circuit, a first coil holder and a second coil holder inserted into the housing are provided, and a spacer is arranged between both coil holders, and torque can be detected based on a change in magnetic resistance in the magnetic circuit. A known torque sensor is known (see Patent Document 1).
Microfilm of Japanese Utility Model Application No. 1-110765 (Japanese Utility Model Application Laid-Open No. 3-48740).

  In such a torque sensor as described above, improvement in torque detection accuracy is desired. An object of the present invention is to provide a torque sensor that can solve such a problem.

The present invention includes a first coil holder and a second coil holder inserted into a housing as constituent members of a magnetic circuit, a spacer is disposed between the two coil holders, and based on a change in magnetic resistance in the magnetic circuit. In a torque sensor capable of detecting torque, the spacer is formed of an insulating material, and the insulating material is made of polyphenylene sulfide as a base material, and the base material is filled with glass fibers. The base material preferably contains 25 to 35% by weight of glass fiber.
According to the configuration of the present invention, the generation of eddy current can be prevented by using polyphenylene sulfide, which is an insulating material, as the material of the spacer, and the size due to shrinkage or warpage can be prevented by filling the base material with glass fiber. A decrease in accuracy can be prevented, and a coefficient of linear expansion can be reduced.

  According to the torque sensor of the present invention, the accuracy of torque detection can be improved.

  A first embodiment of the present invention will be described with reference to FIGS.

  The torque sensor 1 shown in FIG. 1 detects a steering torque in a power steering device of a vehicle.

  The torque sensor 1 includes an aluminum housing 2, an input shaft 3, and an output shaft 4. A steering column 5 is connected to one end of the housing 2. The outer periphery of the input shaft 3 is supported by the inner periphery of the steering column 5 via a bush 12. The outer circumference of the output shaft 4 is supported by the inner circumference of the housing 2 via bearings 13 and 14.

  One end of a steering shaft 6 covered by the steering column 5 is connected to one end of the input shaft 3 by a pin 8. The other end of the steering shaft 6 is connected to a steering wheel (not shown). The torsion bar 7 is inserted into the input shaft 3 and the output shaft 4. One end of the torsion bar 7 is connected to one end of the input shaft 3 by the pin 8, and the other end is connected to the output shaft 4 by a pin 10. Thus, the input shaft 3 and the output shaft 4 are elastically rotatable by the torsion of the torsion bar 7 according to the steering resistance.

  The rotation of the output shaft 4 is transmitted to the wheels via, for example, a rack and pinion type steering gear or the like, so that the wheels are steered. A worm wheel 15 is fitted on the outer periphery of the output shaft 4. The worm wheel 15 meshes with a worm 16 attached to an output shaft of a motor for generating a steering assist force.

  A first detection ring 21 made of a magnetic material is fitted on the outer periphery of the input shaft 3 and fixed by a pin 22. A second detection ring 23 made of a magnetic material is press-fitted to the outer periphery of the output shaft 4. One end face of the first detection ring 21 and the other end face of the second detection ring 23 are arranged so as to face each other, and teeth 21a and 23a are respectively provided on the facing end faces of the detection rings 21 and 23 along the circumferential direction. A plurality is provided. The other end of the first detection ring 21 is a small diameter portion 21b having an outer diameter smaller than the one end.

  A first coil holder 31 made of a magnetic material and a second coil holder 32 made of a magnetic material are built in the housing 2. The outer peripheries of the coil holders 31 and 32 are covered with first and second covering members 61 and 62 described later. The first coil holder 31 holds the first detection coil 33, and the second coil holder 32 holds the second detection coil 34. A spacer 51 is arranged between the first coil holder 31 and the second coil holder 32. The first and second coil holders 31 and 32 are sandwiched between the retaining ring 55 fitted on the inner periphery of the housing 2 and the inner surface 2 d of the housing 2 via the covering members 61 and 62.

  Each of the detection coils 33 and 34 and a printed circuit board 41 disposed outside the housing 2 are connected via wirings 42 and 43 passed through a grommet 49 fitted into a through hole formed in the housing 2. . The signal processing circuit shown in FIG. 3 is formed on the printed board 41. That is, the first detection coil 33 is connected to the oscillator 46 via the resistor 45, the second detection coil 34 is connected to the oscillator 46 via the resistor 47, and the detection coils 33 and 34 are connected to the differential amplifier circuit 48. Is done. Accordingly, the first detection coil 33 generates a magnetic flux that passes through the first detection ring 21, the second detection ring 23, and the first coil holder 31, so that the first detection ring 21, the second detection ring 23, and the first A magnetic circuit including the coil holder 31 as a constituent member is configured. In addition, the second detection coil 34 generates a magnetic flux that passes through the first detection ring 21 and the second coil holder 32, thereby forming a magnetic circuit including the first detection ring 21 and the second coil holder 32 as constituent members. .

  When the torsion bar 7 is elastically twisted by the torque transmission from the input shaft 3 to the output shaft 4, and the first detection ring 21 and the second detection ring 23 rotate relatively, the teeth 21a of the first detection ring 21 The area of the second detection ring 23 facing the teeth 23a changes. The change in the area changes the magnetic resistance of the magnetic circuit. The output of the first detection coil 33 changes based on the change in the magnetic resistance, and the transmission torque is detected according to the output. The outer diameter of the small diameter portion 21b is determined by the magnetic resistance of the magnetic circuit formed by the first detection ring 21 and the second coil holder 32 and the first detection ring 21 and the second detection ring 21 when the steering torque is not applied. The magnetic resistance of the magnetic circuit formed by the detection ring 23 and the first coil holder 31 is set to be equal. As a result, the output fluctuation of the first detection coil 33 due to the temperature fluctuation becomes equal to the output fluctuation of the second detection coil 34 due to the temperature fluctuation. Compensated. The motor is driven according to a signal corresponding to the transmission torque output from the differential amplifier circuit 48, and a steering assist force is applied to the output shaft 4 via the worm 16 and the worm wheel 15.

  As shown in FIG. 2, the first coil holder 31 includes a cylindrical peripheral wall 31 a that covers the outer periphery of the first detection coil 33, an annular side wall 31 b that covers one end of the first detection coil 33, An annular lid 31c that covers the other end of the detection coil 33. The second coil holder 32 includes a cylindrical peripheral wall portion 32 a that covers the outer periphery of the second detection coil 34, an annular side wall portion 32 b that covers one end side of the second detection coil 34, and the other end side of the second detection coil 34. And an annular lid 32c that covers the cover. In each of the coil holders 31, 32, the peripheral walls 31a, 32a and the side walls 31b, 32b are integrally formed, and the lids 31c, 32c are fitted to the inner periphery of the peripheral walls 31a, 32a. The lids 31c and 32c are formed with notches 31c 'and 32c' for passage of the wirings 42 and 43, respectively.

  Each of the detection coils 33 and 34 is configured by winding conductive wires 33b and 34b around bobbins 33a and 34a made of an insulating material.

  Each of the coil holders 31 and 32 and each of the detection rings 21 and 23, which are components of the magnetic circuit, are molded from a magnetic material formed by dispersing magnetic powder in a synthetic resin base material. As the molding method, for example, an injection molding method can be adopted. The synthetic resin material is not particularly limited, and for example, nylon can be used. The magnetic powder is not particularly limited. For example, a Mn-Zn-Fr-based magnetic powder or a Ni-Zn-Fr-based magnetic powder can be used. BSF-547, BSF-400, KNS-415, and Ni-Zn-Fr-based magnetic powder BSN-355B can be used. The magnetic powder has a particle size of 5 μm or less, and preferably contains 90% by weight or more in the magnetic material.

  First and second covering members 61 and 62 in which the outer periphery of the peripheral wall portions 31a and 32a of the coil holders 31 and 32 are molded from a synthetic resin material having higher toughness than the magnetic material forming the coil holders 31 and 32. Covered by The first coil holder 31 and the first covering member 61 are integrated. Further, the second coil holder 32 and the second covering member 62 are integrated. Each of the coil holders 31 and 32 is press-fitted into the housing 2 via each of the covering members 61 and 62.

  The material of each of the covering members 61 and 62 is not particularly limited as long as it is a synthetic resin having higher toughness than the magnetic material forming the coil holders 31 and 32. For example, PP (polypropylene), PBT (polybutylene terephthalate), POM (Polyacetal) or the like can be used. Further, it is preferable that the synthetic resin forming each of the covering members 61 and 62 does not include a reinforcing material such as glass fiber in order to increase toughness as much as possible.

As a molding method of each of the covering members 61 and 62, for example, an injection molding method can be adopted. Further, the peripheral wall portion 31a, the side wall portion 31b, and the first covering member 61 of the first coil holder 31 may be integrated by molding in the same mold, or the molded peripheral wall portion 31a and the side wall may be integrated. The first covering member 61 may be integrated by forming the first covering member 61 in another mold into which the portion 31b is inserted. Similarly, the peripheral wall portion 32a, the side wall portion 32b, and the second covering member 62 of the second coil holder 32 may be integrated by molding in the same molding die, or may be integrated with the molded peripheral wall portion 32a. The second covering member 62 may be integrated in another mold in which the side wall portion 32b is inserted.
In addition, as long as the passage of the magnetic fluxes generated by the detection coils 33 and 34 in the coil holders 31 and 32 is not hindered, the locations where the coil members 31 and 32 are covered by the covering members 61 and 62 are not particularly limited.

  As shown in FIGS. 4 and 5, (1), (2), (3), and FIG. 6, each of the covering members 61, 62 has an annular support wall 61a, 62a and an outer periphery of the support wall 61a, 62a. And three covering walls 61b and 62b supported in a cantilever manner.

  The support wall 61a of the first covering member 61 is integrated with the outer end surface of the side wall 31b of the first coil holder 31. Each coating wall 61b of the first coating member 61 extends along the axial direction of the input / output shafts 3 and 4 from the support wall 61a at three positions at equal intervals in the circumferential direction. It is integrated with the outer peripheral surface of the peripheral wall portion 31a and contacts the outer peripheral surface of the peripheral wall portion 32a of the second coil holder 32. Each covering wall 61b is curved along a circle concentric with the outer periphery of the annular supporting wall 61a, and each circumferential dimension is set to 1/6 of the circumference.

  The support wall 62a of the second covering member 62 is integrated with the outer end surface of the side wall 32b of the second coil holder 32. Each of the coating walls 62b of the second coating member 62 extends along the axial direction of the input / output shafts 3 and 4 from the support wall 62a at three positions at equal intervals in the circumferential direction. It is integrated with the outer peripheral surface of the peripheral wall portion 32a and contacts the outer peripheral surface of the peripheral wall portion 31a of the first coil holder 31. The covering wall 62b is curved along a circle concentric with the outer periphery of the annular support wall 62a, and each circumferential dimension is set to 1/6 of the circumference.

  In the assembly process, the first detection coil 33 is inserted into the peripheral wall 31a of the first coil holder 31 integrated with the first covering member 61, and then the lid 31c is inserted. Further, the second detection coil 34 is inserted into the peripheral wall portion 32a of the second coil holder 32 integrated with the second covering member 62, and then the lid 32c is inserted. Next, the spacer 51 is disposed between the first coil holder 31 and the second coil holder 32, and the two covering members 61 and 62 are brought close to each other along the axial direction of the input / output shafts 3 and 4, The covering wall 62b of the second covering member 62 is arranged between the covering walls 61b of the first covering member 61. Thereafter, as shown in FIGS. 4 and 8, the outer circumferences of the two covering walls 61b and 62b are formed by the elastically deformable arc-shaped stopper 63 made of an insulating material shown in (1) and (2) of FIG. Is covered. The stopper 63 is disposed between convex portions 61b 'and 62b' of the covering walls 61b and 62b, which will be described later, and prevents the covering members 61 and 62 and the coil holders 31 and 32 from separating.

  Resiliently deformable convex portions 61b ', 62b' along the circumferential direction are integrally formed on the outer periphery on the distal end side of each of the coating walls 61b, 62b. In the present embodiment, the covering members 61 and 62 are press-fitted into the housing 2 via the convex portions 61b 'and 62b'. Further, cutouts 61b ", 62b" for passage of the wirings 42, 43 are formed in the respective covering walls 61b, 62b.

As shown in (1) and (2) of FIG. 9, the inner circumference of each of the detection rings 21 and 23 is formed of a synthetic resin material having higher toughness than the magnetic material forming each of the detection rings 21 and 23. The covering members 64 and 65 are integrated.
The material of each of the coating members 64 and 65 is not particularly limited as long as it is higher in toughness than the magnetic material forming the detection rings 21 and 23, and for example, PP, PBT, POM, or the like can be used. Further, it is preferable that the synthetic resin forming each of the covering members 61 and 62 does not include a reinforcing material such as glass fiber in order to increase toughness as much as possible. The thickness of each of the covering members 64 and 65 is preferably about 2 mm so as not to affect the dimensional accuracy.
As a molding method of each of the covering members 64 and 65, for example, an injection molding method can be adopted. Further, each of the detection rings 21 and 23 and each of the covering members 64 and 65 may be integrated by molding in the same mold, or after the detection rings 21 and 23 are molded, the detection rings 21 and 23 may be formed. , 23 may be integrated by molding the covering members 64, 65 in another mold.
As long as the passage of the magnetic flux generated by the detection coils 33 and 34 in the detection rings 21 and 23 is not hindered, the covering portions of the detection rings 21 and 23 by the covering members 64 and 65 are not particularly limited. By covering the inner circumferences of the detection rings 21 and 23, the detection rings 21 and 23 can be smoothly fitted to the outer circumferences of the input / output shafts 3 and 4 (torque transmission shafts), and the detection rings 21 and 23 can be prevented from being damaged during press fitting. .

As shown in FIGS. 10A and 10B, concave portions 51a for passing the wirings 42 and 43 are formed at three positions on the outer periphery of the annular spacer 51, and weights are provided on both sides between the concave portions 51a. A steal portion 51b for reduction is formed. By using an insulating material as the material of the spacer 51, generation of an eddy current can be prevented, and a decrease in torque detection accuracy can be prevented. As an insulating material, a synthetic resin material such as PPS (polyphenylene sulfide) is filled with an inorganic filler such as glass fiber, mica, talc, and CaCO ₃ for the purpose of preventing a decrease in dimensional accuracy due to shrinkage or warpage and reducing a linear expansion coefficient. It is preferable to use a molded product and mold it by injection molding to reduce the processing cost. For example, it is preferable to use an insulating material containing PPS as a base material and containing 25 to 35% by weight of glass fiber and 25 to 35% by weight of an inorganic filler.

  According to the above configuration, since the coil holders 31 and 32 and the detection rings 21 and 23, which are components of the magnetic circuit for torque detection, are molded from a magnetic material, external force or residual stress due to machining acts on the components. Never. Thereby, the magnetic characteristics of the magnetic circuit can be stabilized, and the accuracy of torque detection can be improved. Further, machining costs can be reduced by eliminating machining. Further, the brittleness of the magnetic material constituting the constituent member can be compensated for by the toughness of the synthetic resin material constituting the covering members 61, 62, 64, 65. Further, since the covering members 61 and 62 can receive the force acting when the coil holders 31 and 32 are pressed into the housing 2, the fluctuation of the load acting on the coil holders 31 and 32 is reduced. Further, since the forces acting upon press-fitting the detection rings 21 and 23 into the input / output shafts 3 and 4 can be received by the covering members 64 and 65, fluctuations in the load acting on the detection rings 21 and 23 are reduced. As a result, fluctuations in magnetic characteristics in the magnetic circuit including the coil holders 31 and 32 and the detection rings 21 and 23 are reduced, so that it is possible to prevent a decrease in torque detection accuracy. Further, by supporting the covering members 61 and 62 by the inner periphery of the housing 2 via the elastically deformable convex portions 61b 'and 62b', a space between the outer periphery of the coil holders 31 and 32 and the inner periphery of the housing 2 is obtained. Without setting a high-precision clearance, it is possible to prevent the coil holders 31 and 32 from being pressed against the housing 2 and receiving a large force due to thermal deformation due to temperature fluctuation. Accordingly, it is not necessary to process the coil holders 31 and 32 with high accuracy, the processing cost can be reduced, and the assemblability can be improved.

  The present invention is not limited to the above embodiment. For example, the following modifications can be adopted.

(First Modification)
A first modification of the present invention will be described with reference to (1) and (2) of FIG. Note that the same parts as those in the above embodiment are denoted by the same reference numerals. In the first modified example, the first and second coil holders 31 and 32 and the first and second coil holders 131 and 132 different from the first and second coating members 61 and 62 of the above embodiment and the coating member 161 are used. Have.

  Each of the coil holders 131, 132 is configured by joining two members 131 ', 131 ", 132', 132". In each of the coil holders 131 and 132, one of the members 131 'and 132' is formed integrally with the cylindrical peripheral wall portions 131a and 132a which cover the outer circumferences of the detection coils 33 and 34. And side walls 131b and 132b that cover one end of the detection coils 33 and 34, respectively. In each of the coil holders 131 and 132, the other members 131 ″ and 132 ″ are formed integrally with the cylindrical peripheral wall portions 131c and 132c that cover the outer periphery of the detection coils 33 and 34, respectively. In addition, there are annular side walls 131d, 132d covering the other end sides of the detection coils 33, 34. In each of the coil holders 131 and 132, notches 131d 'and 132d' for passage of the wires 42 and 43 are formed in the side walls 131d and 132d of the other members 131 "and 132". The material of each of the coil holders 131 and 132 is the same as in the above embodiment. The covering member 161 and the coil holders 131 and 132 are individually molded.

  The covering member 161 has an annular supporting wall 161a, four covering walls 161b supported in a cantilever manner by the outer periphery of the supporting wall 161a, and an annular lid member 161c. The first coil holder 131 holding the first detection coil 33, and the second coil holder 132 holding the spacer 51 and the second detection coil 34 are inserted into the covering wall 161b. The support wall 161a contacts the outer end surface of the side wall 131b of the first coil holder 131. Each covering wall 161b extends from its supporting wall 161a in the axial direction of the input / output shafts 3 and 4 at four positions at equal intervals in the circumferential direction, and the peripheral wall portions 131a and 132a of the coil holders 131 and 132. In contact with the outer peripheral surface of Each covering wall 161b is curved so as to follow a circle concentric with the outer periphery of the annular supporting wall 161a. The projection 161c 'formed on the outer periphery of the lid member 161c is fitted into the concave groove 161b "formed on the inner periphery of the other end of each covering wall 161b. The cover member 161 is in contact with the outer end surface of the side wall portion 132b of the 132. The material of the covering member 161 is the same as that of the above embodiment.

  On the outer periphery of each covering wall 161b, an elastically deformable convex portion 161b 'is formed integrally along the circumferential direction. The covering member 161 is press-fitted into the housing 2 via the protrusion 161b '. Others are the same as the above embodiment.

(Second Modification)
A second modification of the present invention will be described with reference to (1) and (2) of FIG. Note that the same parts as those in the above embodiment are denoted by the same reference numerals. This second modification has a covering member 261 and a spacer 251 different from the first and second covering members 61 and 62 and the spacer 51 of the above embodiment.

  The covering member 261 has an arc-shaped covering wall 261b that can be elastically deformed, and fitting portions 261c and 261d formed on both sides of the inner periphery of the covering wall 261b. The inner peripheral surface of the covering wall 261b is in contact with the outer peripheral surfaces of the peripheral wall portions 31a and 32a of the coil holders 31 and 32. One fitting portion 261c is fitted into a groove 31 'formed on the outer periphery of the first coil holder 31. The other fitting portion 261d is fitted into a groove 32 'formed on the outer periphery of the second coil holder 32. The spacer 251 has an arc shape that can be elastically deformed, and is integrated with the inner periphery of the covering member 261. The material of the covering member 261 is the same as in the above embodiment. The spacer 251 is made of the same material as the covering member 261. The covering member 261 and the coil holders 31 and 32 are individually formed. The covering member 261 and the spacer 251 are integrally formed.

  An elastically deformable convex portion 261b 'along the circumferential direction is integrally formed on the outer periphery of the covering wall 261b. The covering member 261 is pressed into the housing 2 via the projection 261b '. Others are the same as the above embodiment.

(Third Modification)
A third modification of the present invention will be described with reference to FIGS. Note that the same parts as those in the above embodiment are denoted by the same reference numerals. The third modified example is different from the first and second covering members 61 and 62 and the first and second detecting coils 33 and 34 of the above embodiment in the first and second covering members 461 and 462 and the first and second covering members. It has two detection coils 433 and 434.

  That is, the first covering member 461 includes a side wall covering portion 461a that covers both end surfaces and the inner peripheral surface of the side wall portion 31b of the first coil holder 31, and a lid covering portion that covers both end surfaces and the inner peripheral surface of the lid 31c. 461b, and a winding portion 461c extending from the cover covering portion 461b toward the side wall covering portion 461a. The side wall portion 31b and the side wall covering portion 461a are integrated, and the lid 31c, the lid covering portion 461b, and the winding portion 461c are integrated.

  The second covering member 462 includes a side wall covering portion 462a that covers both end surfaces and an inner peripheral surface of the side wall portion 32b of the second coil holder 32, and a lid covering portion 462b that covers both end surfaces and the inner peripheral surface of the lid 32c. And a winding portion 462c extending from the cover covering portion 462b toward the side wall covering portion 462a. The side wall portion 32b and the side wall covering portion 462a are integrated, and the lid 32c, the lid covering portion 462b, and the winding portion 462c are integrated.

  The material of each of the covering members 461 and 462 is the same as in the above embodiment. As a molding method of each of the covering members 461 and 462, for example, an injection molding method can be adopted.

  The peripheral wall portion 31a, the side wall portion 31b of the first coil holder 31, and the side wall covering portion 461a of the first covering member 461 may be integrated by molding in the same molding die, or the molded peripheral wall portion may be integrated. The side wall covering portion 461a may be integrated in another mold into which the side wall portion 31a and the side wall portion 31b are inserted. Similarly, the lid 31c, the lid covering portion 461b, and the winding portion 461c may be integrated by being molded in the same molding die, or may be integrated in another die into which the molded lid 31c is inserted. The cover body covering portion 461b and the winding portion 461c may be integrated by molding.

  Further, the peripheral wall portion 32a, the side wall portion 32b of the second coil holder 32, and the side wall covering portion 462a of the second covering member 462 may be integrated by being molded in the same molding die, or may be molded. The side wall covering portion 462a may be integrated in another mold in which the peripheral wall portion 32a and the side wall portion 32b are inserted. Similarly, the lid 32c, the lid covering portion 462b, and the winding portion 462c may be integrated by being molded in the same molding die, or may be integrated into another die into which the molded lid 32c is inserted. The cover body covering portion 462b and the winding portion 462c may be integrated by molding.

  Each of the coil holders 31 and 32 is directly pressed into the housing 2.

  The first and second detection coils 433 and 434 are configured by winding the conductive wires 33b and 34b around the respective winding portions 461c and 462c. This eliminates the need for a dedicated insulating member for winding the conductive wires 33b and 34b constituting the detection coils 433 and 434, thereby reducing the number of parts and improving the assemblability. Others are the same as the above embodiment.

Sectional view of a torque sensor according to an embodiment of the present invention. Sectional view of a main part of a torque sensor according to an embodiment of the present invention. Explanatory drawing of the circuit configuration of the torque sensor according to the embodiment of the present invention. Sectional view in the assembled state of the coil holder, the covering member, and the detection coil of the torque sensor according to the embodiment of the present invention. (1) is a front view, (2) is a cross-sectional view, and (3) is a rear view of the coil holder and the covering member of the torque sensor according to the embodiment of the present invention. FIG. 3 is a side view of the coil holder, the covering member, and the detection coil of the torque sensor according to the embodiment of the present invention. (1) is a side view and (2) is a front view of the stopper of the torque sensor according to the embodiment of the present invention. FIG. 2 is a side view of the torque sensor according to the embodiment of the present invention in an assembled state of a coil holder, a covering member, and a detection coil. In the torque sensor according to the embodiment of the present invention, (1) is a cross-sectional view of a first detection ring, and (2) is a cross-sectional view of a second detection ring. (1) is a front view and (2) is a cross-sectional view of the spacer of the torque sensor according to the embodiment of the present invention. (1) is a front view and (2) is a cross-sectional view of the assembled state of the coil holder, the covering member, and the detection coil of the torque sensor according to the first modified example of the present invention. (1) is a front view and (2) is a cross-sectional view of the assembled state of the coil holder, the covering member, and the detection coil of the torque sensor according to the second modification of the present invention. Sectional drawing of the principal part of the torque sensor of the 3rd modification of this invention. Sectional view of the assembled state of the coil holder, the covering member, and the detection coil of the torque sensor according to the third modified example of the present invention. Sectional view of a peripheral wall, a side wall, and a covering member of a coil holder of a torque sensor according to a third modification of the present invention. Sectional view of a cover and a covering member of a coil holder of a torque sensor according to a third modification of the present invention.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Torque sensor 2 Housing 31, 131 First coil holder 32, 132 Second coil holder 51, 251 Spacer

Claims (2)

As a component of the magnetic circuit, a first coil holder and a second coil holder inserted into the housing are provided,
A spacer is placed between both coil holders,
In a torque sensor capable of detecting torque based on a change in magnetic resistance in the magnetic circuit,
A torque sensor, wherein the spacer is formed of an insulating material, and the insulating material is made of polyphenylene sulfide as a base material, and the base material is filled with glass fibers. The torque sensor according to claim 1, wherein the base material contains 25 to 35% by weight of glass fiber.

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