JP2011089783A - Torque sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the magnetization cost of a torque sensor, and to reduce an influence of variations in the magnetic force between magnetic poles. <P>SOLUTION: A ring-shaped permanent magnet 17 whose inner peripheral side and outer peripheral side have poles different mutually are arranged fixedly, between the first ring portion 15a of a first rotating yoke 15 fixed to a first shaft 11 and the second ring portion 16a of a second rotating yoke 16. The third claw portions 18b of a third rotating yoke 18 fixed to a second shaft 12 and the fourth claw portions 19b of a fourth rotating yoke 19 are arranged, facing the first and second claw portions 15b, 16b of the first and second rotating yokes 15, 16. Magnetic detection elements 22 are provided between a first and second magnetism collecting yokes 20, 21 arranged fixedly, being made to correspond individually to the third and fourth ring portions 18a, 19a of the third and fourth rotating yokes 18, 19. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a torque sensor that detects torsion between a first shaft and a second shaft that are coaxially coupled via a torsion bar.

  A ring-shaped multipolar permanent magnet is fixed to the first shaft connected to the second shaft by a torsion bar, and a pair of rotating yokes each having a claw portion facing the permanent magnet are fixed to the second shaft. A torque sensor configured as described above is known from Patent Document 1.

JP 2008-180517 A

  However, since the multipole permanent magnet is used in the one disclosed in Patent Document 1, not only the magnetization cost is increased, but also the influence of the magnetic force variation between the magnetic poles is increased.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a torque sensor which can reduce the magnetization cost and can also suppress the influence of magnetic force variation between magnetic poles.

  In order to achieve the above object, the present invention provides a torque sensor that detects torsion between a first shaft and a second shaft that are coaxially connected via a torsion bar, and includes a first ring portion and a first ring portion. A first rotating yoke that has a plurality of first claw portions that extend in the axial direction and are connected to a plurality of locations at equal intervals in the circumferential direction, and is fixed to the first shaft; A second ring portion that is formed in a large diameter and coaxially surrounds the first ring portion, and a plurality of first rings that extend in the axial direction and are connected to a plurality of locations at equal intervals in the circumferential direction of the second ring portion. A second rotating yoke having a plurality of second claw portions disposed between the claw portions and fixed to the first shaft, and radially magnetized so that the inner peripheral side and the outer peripheral side have different poles from each other A ring-shaped permanent magnet fixedly disposed between the first and second ring portions, and a third phosphorus And a plurality of third claw portions that are connected to a plurality of locations at equal intervals in the circumferential direction of the first ring portion and the third ring portion, and are fixed to the second shaft with a plurality of third claw portions facing the first and second claw portions. The third rotating yoke, the fourth ring portion formed in the same diameter as the third ring portion, and disposed at a position displaced from the third ring portion in the axial direction of the second axis, and the circumferential direction of the fourth ring portion The second shaft has a plurality of fourth claw portions arranged between the third claw portions so as to be continuously provided at a plurality of positions at equal intervals and to be opposed to the first and second claw portions. A fourth rotating yoke to be fixed, first and second magnetic flux collecting yokes arranged at fixed positions facing the third and fourth ring portions, respectively, and a magnetism provided between the first and second magnetic flux collecting yokes The first feature is that a detection element is provided.

  In addition to the configuration of the first feature, the present invention provides a sensor housing made of synthetic resin that is disposed at a fixed position so as to cover the first to fourth rotating yokes, the permanent magnets, the first and second magnetic flux collecting yokes. Further, the second feature is that the permanent magnet and both the magnetic flux collecting yokes are insert-coupled.

  In addition to the first or second feature of the present invention, the first and second rotating yokes, and a first holder made of synthetic resin in which a part of the first and second rotating yokes are insert-coupled, A first shaft-side rotary yoke body fixed to the first shaft, and a third and fourth rotary yoke, and a second holder made of synthetic resin in which a part of the third and fourth rotary yokes are insert-bonded. A third feature is that the second shaft side rotary yoke body provided is fixed to the second shaft.

  The Hall IC 22 of the embodiment corresponds to the magnetic detection element of the present invention.

  According to the first feature of the present invention, the inner circumferential side and the outer circumferential side are different from each other between the first ring portion of the first rotating yoke and the second ring portion of the second rotating yoke fixed to the first shaft. Since the ring-shaped permanent magnets are fixedly arranged, the first and second claw portions respectively included in the first and second rotating yokes have different magnetic poles. On the other hand, the third claw portion of the third rotating yoke fixed to the second shaft and the fourth claw portion of the fourth rotating yoke are opposed to the first and second claw portions, and the third and fourth rotating yokes. Since the magnetic detection element is provided between a pair of magnetism collecting yokes fixedly arranged corresponding to the third and fourth ring portions individually, if a twist occurs between the first axis and the second axis, The relative position in the circumferential direction between the second claw portion and the third and fourth claw portions changes to change the magnetic flux between the first and second magnetic flux collecting yokes. A twist between the shafts is detected. In addition, since the ring-shaped permanent magnet is magnetized in the radial direction, the magnetizing cost can be reduced, and the influence of the magnetic force variation between the magnetic poles can be reduced.

  According to the second feature of the present invention, when adjusting the variation in magnetic force by changing the sensor setting (e.g., neutral position output), the sensor output can be adjusted only with a torque sensor incorporating a permanent magnet and a magnetic detection element. Therefore, it is possible to reduce the number of steps for assembling the intermediate portion of the steering shaft in the electric power steering apparatus.

  Further, according to the third feature of the present invention, the first shaft side including the first and second rotating yokes and the first holder made of synthetic resin in which a part of the first and second rotating yokes are insert-bonded. Assembling in advance a rotary yoke body including a rotary yoke body, third and fourth rotary yokes, and a second holder made of synthetic resin in which a part of the third and fourth rotary yokes are insert-bonded. By reducing the number of man-hours for assembling the first and second rotating yokes on the first shaft and the man-hours for assembling the third and fourth rotating yokes on the second shaft, the assembling work efficiency can be increased. it can.

It is a longitudinal cross-sectional view of a torque sensor. It is a decomposition | disassembly longitudinal cross-sectional view of a torque sensor. It is a disassembled perspective view of a 1st rotation yoke, a 2nd rotation yoke, a permanent magnet, a 3rd rotation yoke, a 4th rotation yoke, a 1st magnetism collection yoke, and a 2nd magnetism collection yoke. It is a perspective view of the 1st axis | shaft side rotation yoke body fixed to the 1st axis | shaft and the 2nd axis | shaft side rotation yoke body fixed to the 2nd axis | shaft. It is a perspective view of a 1st axis | shaft side rotation yoke body. FIG. 6 is a view taken along arrow 6 in FIG. 5. FIG. 7 is an enlarged cross-sectional view taken along line 7-7 in FIG. 2 in a state where a torsion bar is omitted. It is a disassembled perspective view of the 1st magnetism collection yoke, the 2nd magnetism collection yoke, Hall IC, the 3rd holder, and a terminal. It is a whole perspective view of a torque sensor. It is a figure which shows the relative position change of a 1st-4th nail | claw part.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 10. First, in FIGS. 1 and 2, an intermediate portion of a steering shaft in an electric power steering apparatus is connected by a torsion bar 13. A torque sensor configured according to the present invention is provided so as to detect the twist between the first shaft 11 and the second shaft 12.

  The torque sensor includes a first ring portion 15a and a second ring portion 16a, and first and second rotary yokes 15 and 16 fixed to the first shaft 11, and first and second ring portions 15a and 15a. A ring-shaped permanent magnet 17 fixedly disposed between 16a, and third and fourth rotating yokes 18, 19 having a third ring portion 18a and a fourth ring portion 19a, respectively, and fixed to the second shaft 12. , A pair of magnetic flux collecting yokes 20 and 21 disposed at fixed positions facing the third and fourth ring portions 18a and 19a, respectively, and a Hall IC 22 which is a magnetic detection element provided between the magnetic flux collecting yokes 20 and 21. … And.

  3 and 4, the first rotating yoke 15 includes a first ring portion 15a and a plurality of portions extending in the axial direction, for example, six portions that are provided at equal intervals in the circumferential direction of the first ring portion 15a. .., And six first claw portions 15b, 15b,... Are integrally formed, and the second rotary yoke 16 is formed with a diameter larger than that of the first ring portion 15a and coaxially surrounds the first ring portion 15a. The second ring portion 16a, and a plurality of, for example, six second claw portions 16b, 16b,... Extending in the axial direction and continuously provided at a plurality of locations, for example, six locations, spaced at equal intervals in the circumferential direction of the second ring portion 16a. The first claw portions 15b, 15b ... and the second claw portions 16b, 16b ... have their claw portions 15b, 15b ...; 16b, 16b ... centered on the axis of the first shaft 11. The circumferential direction while keeping the outer surface along the same virtual circle It is formed so as to be mutually arranged.

  5 and 7 together, the first and second rotary yokes 15 and 16, the cylindrical first collar 23 fixed to the first shaft 11 by press-fitting or the like, the first rotary yoke 15, The first holder 24 made of synthetic resin in which a part of the second rotating yoke 16 and the first collar 23 are insert-coupled constitutes a first shaft-side rotating yoke body 25.

  The first holder 24 covers the lower outer periphery of the first collar 23 and connects the first ring portion 15 a of the first rotating yoke 15 and the first collar 23 that are disposed below the first collar 23 with a space therebetween. Downward from the first annular portion 24a so as to fill the axially extending grooves 36 provided at a plurality of, for example, three locations, spaced at equal intervals in the circumferential direction of the outer surface of the first ring portion 15a. And a plurality of, for example, three connecting portions 24b extending to the lower portion of the second rotating yoke 16 and the lower portions of the second ring portion 16a and the first ring portion 15a. The space between the continuous flat plate portion 24c and the first and second claw portions 15b, 15b ...; 16b, 16b ... and the first and second claw portions 15b, 15b ...; And a first cylindrical portion 24d which extends in a cylindrical shape on the side connected to the outer periphery of the flat plate portion 24c integrally. Thus, the portion of the outer periphery of the first ring portion 15a of the first rotating yoke 15 excluding the connecting portion 24b ... while being held by the first holder 24 is the second ring portion 16a side of the second rotating yoke 16. The first and second claw portions 15b, 15b,... 16b, 16b are exposed to the first ring portion 15a and the entire inner circumference of the second ring portion 16a of the second rotary yoke 16 is exposed. The outer surface of... Faces outward along the same virtual circle centered on the axis of the first shaft 11.

  The permanent magnet 17 is formed in a ring shape by being magnetized in the radial direction so that the inner peripheral side and the outer peripheral side are different from each other, and is fixedly disposed between the first and second ring portions 15a, 16a. The inner periphery of the permanent magnet 17 facing the outer periphery of the first ring portion 15a in the first rotating yoke 15 is magnetized, for example, to the N pole, whereas the second ring portion 16a in the second rotating yoke 16 is The outer periphery of the permanent magnet 17 facing the inner periphery is magnetized, for example, to an S pole.

  The third rotating yoke 18 includes a third ring portion 18a and a plurality of, for example, six third claw portions 18b provided continuously at a plurality of locations, for example, six locations at equal intervals in the circumferential direction of the third ring portion 18a. 18b ..., and the fourth rotating yoke 19 includes a fourth ring portion 19a and a plurality of, for example, a plurality of, for example, six portions provided at equal intervals in the circumferential direction of the fourth ring portion 19a. It has six 4th nail | claw parts 19b, 19b ... integrally. Thus, the third ring portion 18a and the fourth ring portion 19a are formed to have the same diameter and are disposed at positions shifted from each other in the axial direction of the second axis, and the third claw portions 18b, 18b,. The claw portions 19b, 19b ... are formed so as to extend in the axial direction so that the claw portions 18b, 18b ...; 19b, 19b ... are alternately arranged in the circumferential direction, and the third and fourth rotary yokes 18, The first and second rotating yokes 19 have the third and fourth claw portions 18b, 18b... 19b, 19b... With their inner surfaces along the same virtual circle centered on the axis of the second shaft 12. The first and second claw portions 15b, 15b ...; 16b, 16b ... are arranged so as to face the outer sides in the radial direction.

  Further, the third and fourth rotating yokes 18 and 19, the cylindrical second collar 26 fixed to the second shaft 12 by press-fitting or the like, the third rotating yoke 18, the fourth rotating yoke 19, and the second collar 26. The second holder 27 made of synthetic resin, part of which is insert-bonded, constitutes a second shaft-side rotary yoke body 28.

  The second holder 27 covers the upper outer periphery of the second collar 26 and connects the fourth ring portion 19 a of the fourth rotating yoke 19 and the second collar 26 disposed above the second collar 26 with a space therebetween. The second annular portion 27a and the third and fourth ring portions 18a, 19a located at positions separated from each other in the upper axial direction of the second collar 26 are connected to each other and the third and fourth claw portions 18b, 18b,. 19b, 19b... Are integrally provided with a second cylindrical portion 27b connected to the upper portion of the second annular portion 27a so as to fill the space, and are held by the second holder 27 so that the third and fourth rotating yokes are provided. The inner surfaces of the third and fourth claw portions 18b, 18b... 19b, 19b... At 18 and 19 are flush with the inner peripheral surface of the second cylindrical portion 27b of the second holder 27.

  Referring also to FIG. 8, the first and second magnetic collecting yokes 20, 21 are arc portions 20 a, 21 a formed in an arc shape centering on the axis of the second shaft 12, and arc portions 20 a, 21 a. The magnetic flux collecting portions 20b, 20b; 21b, 21b projecting outward in the radial direction from the central portion in the circumferential direction are integrally formed, and are formed in the same shape. The rotating yoke 18 is arranged so as to oppose the outer periphery of the third ring portion 18a and the inner periphery of the arc portion 21a is arranged to oppose the outer periphery of the fourth ring portion 19a in the fourth rotating yoke 19, and both the magnetism collecting portions 20b, 21b. ; Hall ICs 22 and 22 are provided between 20b and 21b.

  Moreover, the magnetism collecting portions 20b, 20b; 21b, 21b are projected at two locations spaced apart in the circumferential direction of the arc portions 20a, 21a in the first and second magnetism collecting yokes 20, 21, and two pairs forming a pair The Hall ICs 22 and 22 are provided between the magnetism collecting portions 20b and 21b; 20b and 21b, respectively, and when one Hall IC 22 fails, the other Hall IC 22 can detect.

  Referring also to FIG. 9, the first to fourth rotating yokes 15, 16, 18, 19, the permanent magnet 17, and the first and second magnetic collecting yokes 20, 21 are made of synthetic resin and arranged at fixed positions. An annular support projection 17a provided integrally with the permanent magnet 17 and projecting in the axial direction; and outer peripheral sides of the first and second magnetic flux collecting yokes 20 and 21; Are insert-coupled to the sensor housing 30.

  Moreover, the first and second magnetic flux collecting yokes 20, 21 and the magnetic flux collecting portions 20b, 21b of the magnetic flux collecting yokes 20, 21; Hall ICs 22 provided between the magnetic flux collecting portions 20b, 21b; 8 are assembled to an arc-shaped third holder 31 made of synthetic resin, as shown in FIG. 8, and the first and second magnetic flux collecting yokes 20 and 21, the Hall IC 22. The third holder 31 in the assembled state is molded and coupled to the sensor housing 30 when the sensor housing 30 is molded. The sensor housing 30 is integrally formed with a connector portion 30a, and the terminals 32 are arranged in the connector portion 30a.

  The sensor housing 30 is fixed to a vehicle body (not shown), and cylindrical third collars 37 are inserted and connected to a plurality of, for example, three portions of a flange portion 30a provided integrally with the sensor housing 30. The sensor housing 30 is fixed to the vehicle body side by bolts (not shown) inserted through the third collars 37.

  Further, a ball bearing 33 and a dust seal 34 disposed outside the ball bearing 33 are interposed between the sensor housing 30 and the first shaft 11. The first shaft side rotary yoke body 25 is fixed to the first shaft 11, and the second shaft side rotary yoke body 28 is fixed to the second shaft 12 connected to the first shaft 11 via the torsion bar 13. The sensor housing 30 to which the first and second magnetism collecting yokes 20 and 21 are insert-coupled includes the first and second ring portions 15a of the first and second rotating yokes 15 and 16 in the first shaft-side rotating yoke body 25. 16a, the permanent magnet 17 is arranged between the first shaft 11 side so as to cover the torsion bar 13, the first shaft side rotating yoke body 25 and the second shaft side rotating yoke body 28. It is.

  Next, the operation of this embodiment will be described. The first ring portion 15a and the plurality of first claw portions extending in the axial direction are provided at a plurality of positions spaced at equal intervals in the circumferential direction of the first ring portion 15a. The first rotating yoke 15 having 15b, 15b..., The second ring portion 16a formed in a larger diameter than the first ring portion 15a and coaxially surrounding the first ring portion 15a and the circumferential direction of the second ring portion 16a Second rotation having a plurality of second claw portions 16b, 16b... Arranged in a plurality of positions at equal intervals and extending in the axial direction and disposed between the plurality of first claw portions 15b, 15b. A ring-shaped permanent magnet 17 is fixed between the first and second ring portions 15a and 16a, with the yoke 16 fixed to the first shaft 11 and radially magnetized so that the inner and outer peripheral sides have different poles. Fixedly placed on the third A plurality of third portions which are continuously provided at a plurality of positions spaced at equal intervals in the circumferential direction of the ring portion 18a and the third ring portion 18a and which face the first and second claw portions 15b, 15b,. The third rotating yoke 18 having the claw portions 18b, 18b... A, and the fourth ring portion 19a that is formed to have the same diameter as the third ring portion 18a and is displaced from the third ring portion 18a in the axial direction. In addition, the third claw portion 18b is connected to a plurality of locations at equal intervals in the circumferential direction of the fourth ring portion 19a and is opposed to the first and second claw portions 15b, 15b... 16b, 16b. A fourth rotating yoke 19 having a plurality of fourth claw portions 19b, 19b,... Disposed between 18b... Is fixed to the second shaft 12, and faces the third and fourth ring portions 18a, 19a, respectively. In a fixed position Hall IC 22 ... are provided between the first and second magnetic flux collecting yokes 20 and 21 to be location.

  In such a torque sensor 14, in a state where there is no twist between the first shaft 11 and the second shaft 12, as shown in FIG. 10 (a), the first claw portion 15b ... and the second claw portion 16b ... It is in the neutral state corresponding to between 3rd and 4th nail | claw part 18b ..., 19b .... When the first shaft 11 rotates in one direction (the direction indicated by the arrow 38 in FIG. 10) from this neutral state, as shown in FIG. 10 (b), one of the N pole and the S pole in the permanent magnet 17 (this In the embodiment, the first claw portion 15b of the first rotating yoke 15 with the first ring portion 15a opposed to the N pole) has many portions that overlap the fourth claw portion 19b of the fourth rotating yoke 19 in the radial direction. The second claw portion 16b of the second rotating yoke 16 with the second ring portion 16a facing the other of the N pole and the S pole (in this embodiment, the S pole) of the permanent magnet 17 is the third rotating yoke 18. The number of portions that overlap the third claw portions 18b in the radial direction increases. In this state, from the north pole of the permanent magnet 17 to the first rotating yoke 15, the fourth rotating yoke 19, the magnetic collecting parts 21 b of the second magnetic collecting yoke 21, the Hall IC 22, and the magnetic collecting parts of the first magnetic collecting yoke 20. The magnetic flux flows to the south pole of the permanent magnet 17 through 20b, the third rotating yoke 19, and the second rotating yoke 16. Thus, the first claw portion 15b of the first rotating yoke 15 with the first ring portion 15a opposed to the N pole on the inner peripheral side of the permanent magnet 17 and the fourth claw portion 19b of the fourth rotating yoke 19. Radial overlap between the second claw portions 16b of the second rotating yoke 16 and the third claw portions 18b of the third rotating yoke 18 with the second ring portion 16a facing the outer circumferential side of the permanent magnet 17 As the amount, that is, the amount of twist of the first shaft 11 in the one direction relative to the second shaft 12 increases, the magnetic flux density increases.

  When the first shaft 11 is rotated in the other direction (the direction indicated by the arrow 39 in FIG. 10) from the neutral state, as shown in FIG. 10 (c), the first pawl portion 15b of the first rotating yoke 15. Of the third rotating yoke 18 overlaps with the third claw portions 18b in the radial direction, and the second claw portion 16b of the second rotating yoke 16 has a radius on the fourth claw portion 19b of the fourth rotating yoke 19. More parts overlap in the direction. In this state, from the north pole of the permanent magnet 17 to the first rotating yoke 15, the third rotating yoke 18, the magnetic collecting parts 20 b of the first magnetic collecting yoke 20, the Hall IC 22, and the magnetic collecting parts of the second magnetic collecting yoke 21. The magnetic flux flows to the south pole of the permanent magnet 17 through 21b, the fourth rotating yoke 19, and the second rotating yoke 16. Thus, the first claw portion 15b of the first rotating yoke 15 with the first ring portion 15a opposed to the N pole on the inner peripheral side of the permanent magnet 17 and the third claw portion 18b of the third rotating yoke 18. The radial overlap between the second claw portions 16b of the second rotating yoke 16 and the fourth claw portions 19b of the fourth rotating yoke 19 with the second ring portion 16a facing the outer circumferential side of the permanent magnet 17 As the amount, that is, the amount of twist of the first shaft 11 in the other direction with respect to the second shaft 12 increases, the magnetic flux density increases.

  In this way, the first claw portion 15b of the first rotary yoke 15 and the second claw portion 16b of the second rotary yoke 16, the third claw portion 18b of the third rotary yoke 18, and the fourth rotary yoke 19 are formed. Change in the circumferential relative position with respect to the fourth claw portions 19b... Changes in the magnetic flux between the first and second magnetic flux collecting yokes 20 and 21, thereby causing the first shaft 11 and the first A twist between the two shafts 12 is detected. In addition, since the ring-shaped permanent magnet 17 is magnetized in the radial direction, the magnetizing cost can be reduced, and the influence of the magnetic force variation between the magnetic poles can be reduced.

  In addition, the sensor housing 30 made of synthetic resin, which is disposed at a fixed position, covers the first to fourth rotating yokes 15, 16, 18, 19, the permanent magnet 17, and the first and second magnetic flux collecting yokes 20, 21, permanently. Since the magnet 17 and the first and second magnetic collecting yokes 20 and 21 are insert-coupled, the permanent magnet 17 and the Hall IC 22... Are adjusted when the variation in magnetic force is adjusted by changing the sensor setting (e.g., neutral position output). Since the sensor output can be adjusted only by the torque sensor with the built-in motor, it is possible to reduce the number of assembling steps to the intermediate portion of the steering shaft in the electric power steering apparatus.

  Further, the first and second rotating yokes 15 and 16, a first holder 24 made of synthetic resin in which a part of the first and second rotating yokes 15 and 16 are insert-bonded, and a first collar 23 are provided. A shaft-side rotating yoke body 25 is fixed to the first shaft 11, and the third and fourth rotating yokes 18, 19 and a part of the third and fourth rotating yokes 18, 19 are insert-bonded and made of synthetic resin. Since the second shaft-side rotary yoke body 28 including the two holders 27 and the second collar 27 is fixed to the second shaft 12, the first shaft-side rotary yoke body 25 and the second shaft-side rotary yoke body 28 are preliminarily attached. By assembling, the man-hours for assembling the first and second rotating yokes 15, 16 to the first shaft 11 and the man-hours for assembling the third and fourth rotating yokes 18, 19 to the second shaft 12 are reduced. To improve assembly work efficiency It can be.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. Is possible.

DESCRIPTION OF SYMBOLS 11 ... 1st axis | shaft 12 ... 2nd axis | shaft 13 ... Torsion bar 15 ... 1st rotation yoke 15a ... 1st ring part 15b ... 1st nail | claw part 16 ... 2nd Rotating yoke 16a ... second ring portion 16b ... second claw portion 17 ... permanent magnet 18 ... third rotating yoke 18a ... third ring portion 18b ... third claw portion 19 .. 4th rotating yoke 19a ... 4th ring part 19b ... 4th claw part 20 ... 1st magnetism collecting yoke 21 ... 2nd magnetism collecting yoke 22 ... hole which is a magnetic detection element IC
24 ... 1st holder 25 ... 1st axis | shaft side rotation yoke body 27 ... 2nd holder 28 ... 2nd axis | shaft side rotation yoke body 30 ... Sensor housing

Claims (3)

  A torque sensor for detecting torsion between a first shaft (11) and a second shaft (12) connected coaxially via a torsion bar (13), the first ring portion (15a) and the first ring portion First rotation fixed to the first shaft (11) having a plurality of first claw portions (15b) extending in the axial direction and connected to a plurality of locations at equal intervals in the circumferential direction of (15a) The circumference of the yoke (15), the second ring portion (16a) and the second ring portion (16a) which are formed larger in diameter than the first ring portion (15a) and coaxially surround the first ring portion (15a). A plurality of second claw portions (16b) arranged in a plurality of locations at equal intervals in the direction and extending in the axial direction and having a tip portion disposed between the tip portions of the plurality of first claw portions (15b) A second rotating yoke (16) fixed to the first shaft (11) and an inner peripheral side A ring-shaped permanent magnet (17) which is magnetized in the radial direction so that the outer peripheral sides are different from each other and fixed between the first and second ring portions (15a, 16a), and a third ring portion (18a) and a plurality of third ring portions (18a) that are connected to a plurality of locations at equal intervals in the circumferential direction and that have the tip portions opposed to the tip portions of the first and second claw portions (15b, 16b). A third rotating yoke (18) having a third claw portion (18b) and being fixed to the second shaft (12); and a second shaft formed with the same diameter as the third ring portion (18a). The fourth ring portion (19a) and the fourth ring portion (19a) arranged at positions displaced from the third ring portion (18a) in the axial direction of (12) are continuously provided at a plurality of positions spaced at equal intervals in the circumferential direction. At the tip of the first and second claw portions (15b, 16b) A fourth rotation having a plurality of fourth claw portions (19b) arranged between the tip portions of the third claw portions (18b) so that the end portions are opposed to each other and fixed to the second shaft (12) The first and second magnetic flux collecting yokes (20, 21), the first and second magnetic flux collecting yokes, which are disposed at fixed positions facing the yoke (19), the third and fourth ring portions (18a, 19a), respectively. A torque sensor comprising a magnetic detection element (22) provided between the magnetic yokes (20, 21).   Made of synthetic resin, which is disposed at a fixed position covering the first to fourth rotating yokes (15, 16, 18, 19), the permanent magnet (17), the first and second magnetic collecting yokes (20, 21). The torque sensor according to claim 1, wherein the permanent magnet (17) and the magnetic flux collecting yokes (20, 21) are insert-coupled to the sensor housing (30).   A first shaft including first and second rotating yokes (15, 16) and a first holder (24) made of synthetic resin in which a part of the first and second rotating yokes (15, 16) is insert-bonded. The side rotary yoke body (25) is fixed to the first shaft (11), and the third and fourth rotary yokes (18, 19) and a part of the third and fourth rotary yokes (18, 19) are insert-coupled. The torque sensor according to claim 1 or 2, wherein a second shaft side rotary yoke body (28) provided with a second holder (27) made of synthetic resin is fixed to the second shaft (12). .

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