Magnetostrictive torgue sensor

Abstract

To achieve a structure of a magnetostrictive torque sensor capable of easily securing mounting properties to a stationary part.SOLUTION: A magnetostrictive torque sensor, which is a sensor that measures a torque applied to a rotary axis having magnetostrictive characteristics, includes a holder 4, a cover 5, a flexible substrate and a connector 7. The cover 5 closing an opening of a storage recess 13 provided in the holder 4 is provided with a connector support 26 for supporting the connector 7. Accordingly, the sensor can favorably secure mounting properties to a stationary part of the magnetostrictive torque sensor while suppressing an increase in manufacturing cost.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a magnetostrictive torque sensor that measures torque applied to a rotating shaft. [Background technology]

[0002] As a sensor for measuring the torque applied to a rotating shaft, a magnetostrictive torque sensor that measures the torque applied to a rotating shaft by utilizing the inverse magnetostrictive effect that occurs in the rotating shaft when torque is applied to the rotating shaft has been known for some time, for example as described in JP 2022-74405 A.

[0003] The torque sensor described in JP 2022-74405 A places a flexible substrate on which multiple detection coils are printed around a rotating shaft, and detects the torque applied to the rotating shaft based on changes in inductance of the detection coils.

[0004] In the torque sensor described in JP 2022-74405 A, the flexible substrate is accommodated inside a resin housing. A signal line is connected to each of the detection coils printed on the flexible substrate. The signal lines are bundled into a single cable inside a rectangular cylindrical guide portion provided in the resin housing so as to protrude radially outward, and are drawn out to the external space through the guide portion. The cable is connected to a detection circuit provided outside.

[0005] In the torque sensor described in JP 2022-74405 A, the detection coil for detecting the change in inductance is configured by a detection coil printed on a flexible substrate. That is, according to the torque sensor described in JP 2022-74405 A, since it is not necessary to configure each detection coil by winding an insulated wire around a holder, it is possible to reduce manufacturing costs. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2022-74405 Summary of the Invention [Problem to be solved by the invention]

[0007] In the torque sensor described in JP 2022-74405 A, the signal lines connected to the detection coil of the flexible substrate are bundled into a single cable inside a rectangular cylindrical guide portion provided in a resin housing so as to protrude radially outward, and are drawn out to the external space through the guide portion. For this reason, depending on the shape of the portion where the torque sensor is attached and the direction of the cable connection, the cable handling work may become cumbersome, and the assembly man-hours may increase, resulting in higher assembly costs.

[0008] It is possible to change the shape of the guide part and change the cable pull-out direction depending on the shape of the part where the torque sensor is attached and the direction of the cable connection destination, etc. In this case, however, multiple types of molds must be prepared to manufacture multiple resin housings with different guide part shapes, which may increase the manufacturing cost of the torque sensor.

[0009] An object of the present disclosure is to realize a magnetostrictive torque sensor structure that can easily ensure attachment to a fixed portion. [Means for solving the problem]

[0010] A magnetostrictive torque sensor according to a first aspect of the present disclosure is a sensor that measures torque applied to a rotating shaft having magnetostrictive properties, and includes a holder, a cover, a flexible substrate, and a connector.

[0011] The holder has an inner cylindrical portion arranged around the rotating shaft, a side plate portion bent radially outward from one axial end of the inner cylindrical portion, an outer cylindrical portion bent from the radially outer end of the side plate portion toward the other axial side, and an accommodating recess that connects an inner space located radially inside the outer cylindrical portion and an outer space located radially outside the outer cylindrical portion and is open on the other axial side.

[0012] The cover closes an opening on the other axial side of the accommodating recess.

[0013] The flexible substrate has a detection section including a plurality of detection coils and arranged around the inner cylindrical portion, and a signal line section including a plurality of signal lines electrically connected to the plurality of detection coils, a portion of which is accommodated inside the accommodating recess.

[0014] The connector is attached to the tip end of the signal line portion.

[0015] In particular, in the magnetostrictive torque sensor according to the first aspect of the present disclosure, the cover has a connector support portion for supporting the connector.

[0016] In the magnetostrictive torque sensor of the second aspect of the present disclosure, in the magnetostrictive torque sensor of the first aspect of the present disclosure, the cover has a blocking plate portion that blocks the opening on the other axial side of the accommodating recess, and a support plate portion that includes the connector support portion.

[0017] In a magnetostrictive torque sensor of a third aspect of the present disclosure, in the magnetostrictive torque sensor of the first or second aspect of the present disclosure, the connector support portion is formed by a slit, and the connector is supported on the cover by engaging a part of the connector with the slit.

[0018] In a magnetostrictive torque sensor of a fourth aspect of the present disclosure, in a magnetostrictive torque sensor of any of the first to third aspects of the present disclosure, the cover has a convex portion arranged inside the accommodating recess, one of the accommodating recess and the convex portion has a convex corner portion that increases the contact surface pressure with the signal line portion when the signal line portion is pulled toward the outer space, and the other of the accommodating recess and the convex portion has a concave corner portion that faces the convex corner portion.

[0019] A magnetostrictive torque sensor according to a fifth aspect of the present disclosure is the magnetostrictive torque sensor according to any one of the first to fourth aspects of the present disclosure, further comprising a magnetic ring disposed around the detection portion.

[0020] In the magnetostrictive torque sensor of the sixth aspect of the present disclosure, in the magnetostrictive torque sensor of the fifth aspect of the present disclosure, the holder has a cylindrical holder-side mating surface and a holder-side locking hole, and the magnetic ring has a ring-side mating surface that mates with the holder-side mating surface and a ring-side locking hole. Furthermore, the magnetostrictive torque sensor of the sixth aspect of the present disclosure includes a positioning member that is stretched across the holder-side locking hole and the ring-side locking hole.

[0021] In the magnetostrictive torque sensor according to one aspect of the present disclosure, in the torque sensor according to the sixth aspect of the present disclosure, the holder-side fitting surface and the ring-side fitting surface can be fitted together without any rattle in the radial direction. In this case, specifically, the holder-side fitting surface and the ring-side fitting surface can be fitted together by a spigot-fit, which is a clearance fit without any rattle in the radial direction.

[0022] In one embodiment of the magnetostrictive torque sensor disclosed herein, the holder side engagement hole can be radially inserted through the holder, and the positioning member can be radially protruded from one of the openings on either radial side of the holder side engagement hole, the opening opposite the magnetic ring side in the radial direction.

[0023] The magnetostrictive torque sensor according to an aspect of the present disclosure may include a plurality of combinations of the holder-side locking hole, the ring-side locking hole, and the positioning member, or may include one combination of the holder-side locking hole, the ring-side locking hole, and the positioning member.

[0024] In the magnetostrictive torque sensor according to an aspect of the present disclosure, the positioning member may be a spring pin. Alternatively, the positioning member may be a columnar or cylindrical pin, a screw, or the like.

[0025] In a magnetostrictive torque sensor according to one aspect of the present disclosure, the holder-side mating surface can be provided on an inner peripheral surface of the outer cylindrical portion, and the ring-side mating surface can be provided on an outer peripheral surface of the magnetic ring.

[0026] When implementing the magnetostrictive torque sensor of the present disclosure, the above-described aspects can be implemented in any suitable combination as long as no contradiction occurs. Effect of the Invention

[0027] According to the magnetostrictive torque sensor of the present disclosure, it is possible to easily ensure the attachability to the fixed portion. [Brief description of the drawings]

[0028] [Figure 1] FIG. 1 is a perspective view showing a magnetostrictive torque sensor according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a perspective view showing the magnetostrictive torque sensor of the first example, as viewed from the opposite side to FIG. 1 in the axial direction. [Diagram 3] FIG. 3 is an exploded perspective view showing the magnetostrictive torque sensor of the first example. [Figure 4] FIG. 4 is an exploded perspective view showing the magnetostrictive torque sensor of the first example, as viewed from the opposite side to FIG. 3 in the axial direction. [Diagram 5] FIG. 5 is a cross-sectional view of the magnetostrictive torque sensor of the first example. [Figure 6] FIG. 6 is a partially enlarged cross-sectional view showing a detection portion of the flexible substrate. [Figure 7] 7(a) to 7(d) are developments of the first to fourth wiring layers as viewed from the radially outer side. [Figure 8] FIG. 8 is a diagram showing a schematic diagram of a detection circuit including four detection coils. [Figure 9] FIG. 9 is a development view of the flexible substrate. [Figure 10] FIG. 10(a) is an end view of the first example magnetostrictive torque sensor, as viewed from the lower left side of FIG. 1 in the axial direction, with the support plate portion, connector, and magnetic ring that constitute the cover omitted, and FIG. 10(b) is an end view of FIG. 10(a) with the cover omitted. [Figure 11] FIG. 11(a) is a partially enlarged view of the holder receiving portion as viewed from the axial direction, and FIG. 11(b) is a partially enlarged perspective view showing the peripheral portion of the holder receiving portion with a part cut away. [Figure 12] FIG. 12(a) is a perspective view showing a closing plate portion of the cover, and FIG. 12(b) is a view seen from the opposite side to FIG. 12(a). [Figure 13] FIG. 13 is a cross-sectional view showing the state in which the magnetostrictive torque sensor of the first example is attached to a fixed portion. [Figure 14] 14(a) to 14(c) are partially enlarged cross-sectional views showing three examples of modified shapes of the accommodating recess and the protrusion of the cover. [Figure 15] FIG. 15 is a perspective view showing another example of a supporting form of the connector. [Figure 16] FIG. 16 is a perspective view seen from the opposite side to FIG. 15 in the axial direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] [Example 1] A first example of an embodiment of the present disclosure will be described with reference to FIGS. 1 to 16. FIG.

[0030] The magnetostrictive torque sensor 1 of this example is a sensor that measures the torque applied to a rotating shaft 2, and is used while being supported and fixed to a fixed part 3 that does not rotate even when in use, such as a housing. The magnetostrictive torque sensor 1 includes a holder 4, a cover 5, a flexible substrate 6, and a connector 7. Furthermore, the magnetostrictive torque sensor 1 of this example includes a magnetic ring 8 and positioning members 9a and 9b.

[0031] In the following description, unless otherwise specified, the axial, radial, and circumferential directions of the magnetostrictive torque sensor 1 refer to the axial, radial, and circumferential directions of the rotating shaft 2. The axial, radial, and circumferential directions of the rotating shaft 2 coincide with the axial, radial, and circumferential directions of the holder 4 and also coincide with the axial, radial, and circumferential directions of the magnetic ring 8. Moreover, one axial side refers to the right side in FIG. 5, and the other axial side refers to the left side in FIG. 5.

[0032] The holder 4 has an inner cylindrical portion 10 , a side plate portion 11 , an outer cylindrical portion 12 , and an accommodating recess 13 .

[0033] The inner cylindrical portion 10 is disposed around the rotating shaft 2 coaxially with the rotating shaft 2 in a state in which the magnetostrictive torque sensor 1 is supported and fixed to the fixed portion 3 .

[0034] In this example, the inner tubular portion 10 has a cylindrical shape. That is, the inner tubular portion 10 has an inner peripheral surface whose inner diameter does not change along the axial direction, and an outer peripheral surface whose outer diameter does not change along the axial direction.

[0035] The side plate portion 11 is bent radially outward from one axial end of the inner cylindrical portion 10. The radially outer end of the side plate portion 11 is connected to one axial end of the outer cylindrical portion 12. In other words, the side plate portion 11 connects one axial end of the inner cylindrical portion 10 and one axial end of the outer cylindrical portion 12. The outer cylindrical portion 12 is also arranged coaxially with the inner cylindrical portion 10.

[0036] In this example, the side plate portion 11 is bent radially outward from one axial end portion of the inner tubular portion 10 excluding a portion where the accommodating recess 13 is provided. That is, in this example, the side plate portion 11 has a substantially C-shaped end face shape when viewed from the axial direction.

[0037] The outer tubular portion 12 is bent from the radially outer end of the side plate portion 11 toward the other axial side, except for a portion where the accommodating recess 13 is provided. That is, the outer tubular portion 12 has a partially cut cylindrical shape as a whole.

[0038] In this example, the axial length of the outer tubular portion 12 is shorter than the axial length of the inner tubular portion 10. Therefore, the other axial side portion of the inner tubular portion 10 also protrudes toward the other axial side near the other axial side end of the outer tubular portion 12.

[0039] The accommodating recess 13 communicates between an inner space present on the radial inside of the outer tubular portion 12 and an outer space present on the radial outside of the outer tubular portion 12, and is open on the other axial side.

[0040] The holder 4 of this embodiment includes a bottom plate portion 14 and two side walls 15a, 15b each for forming an accommodating recess 13.

[0041] The bottom plate portion 14 is configured in a generally rectangular flat plate shape. One axial side of the bottom plate portion 14 is flush with one axial side of the side plate portion 11, and the other axial side of the bottom plate portion 14 is flush with the other axial side of the side plate portion 11.

[0042] The side walls 15a, 15b protrude from both circumferential portions of the side surface of the bottom plate portion 14 on the other axial side toward the other axial side.

[0043] As shown in Figures 10(b) to 11(b), the accommodating recess 13 is formed by a portion surrounded on three sides by the other axial side of the bottom plate portion 14 and the opposing opposing surfaces 16a, 16b of the side wall portions 15a, 15b.

[0044] Of the two side walls 15a, 15b, the opposing surface 16a of one side wall 15a is configured by connecting a holder-side first guide surface 17 on the radial inner side and a holder-side second guide surface 18 on the radial outer side by a holder-side inclined guide surface 19. The holder-side second guide surface 18 is disposed offset toward the other side wall 15b from the holder-side first guide surface 17. The holder-side first guide surface 17 and the holder-side second guide surface 18 are disposed approximately parallel to each other. The holder-side inclined guide surface 19 is inclined in a direction approaching the other side wall 15b as it moves radially outward.

[0045] The opposing surface 16b of the other side wall portion 15b is configured by connecting a holder-side first flat surface 20 on the radially inner side and a holder-side second flat surface 21 on the radially outer side by a step surface 22 facing radially inward. The holder-side second flat surface 21 is disposed offset toward the side closer to one side wall portion 15a than the holder-side first flat surface 20. The holder-side first flat surface 20 and the holder-side second flat surface 21 are disposed approximately parallel to each other.

[0046] Each of the side walls 15a, 15b has a flat seat surface 23a, 23b on the other axial side and perpendicular to the central axis of the holder 4. The seat surfaces 23a, 23b of the side walls 15a, 15b are offset toward one axial side from the remaining portions.

[0047] The holder 4 further has a holder-side fitting surface 24 having a cylindrical surface shape, and a holder-side locking hole 25 .

[0048] In this example, the holder side fitting surface 24 is provided on the inner circumferential surface of the outer tubular portion 12. Specifically, the holder side fitting surface 24 is provided on the entire inner circumferential surface of the outer tubular portion 12, and is configured of a single cylindrical surface whose inner diameter does not change in the axial direction.

[0049] The holder-side locking holes 25 are provided so as to penetrate radially through one or more circumferential locations of the outer tubular portion 12. In this example, the holder-side locking holes 25 are provided at five circumferentially equally spaced locations in a portion of the outer tubular portion 12 that is circumferentially offset from the portion where the accommodating recess 13 is provided.

[0050] The holder 4 is made of synthetic resin, which is a non-magnetic and non-conductive (insulating) material. Specifically, the holder 4 is made of thermoplastic resin such as epoxy resin, polyphenylene sulfide (PPS), PA (polyamide), or PPA (polyphthalamide). In this example, the holder 4 is integrally formed as a whole by injection molding of synthetic resin. However, when implementing the magnetostrictive torque sensor of the present disclosure, the holder can also be formed by combining multiple parts.

[0051] The cover 5 closes the opening on the other axial side of the accommodating recess 13. The cover 5 also has a connector support portion 26 for supporting the connector 7.

[0052] The cover 5 has a support plate portion 27 including a connector support portion 26, and a closing plate portion 28 that closes the opening of the accommodating recess 13 on the other axial side.

[0053] In this example, the support plate 27 is configured in a substantially rectangular plate shape. The support plate 27 has a recess 29 on one axial side, and slits (recessed grooves) 30a, 30b on circumferentially opposing side surfaces of the recess 29. In this example, the connector 7 is supported relative to the cover 5 by engaging the widthwise edge portions of the supported plate portion 79 of the connector 7 with the slits 30a, 30b. That is, in this example, the connector support portion 26 is configured by the slits 30a, 30b.

[0054] The closing plate portion 28 is configured in a substantially rectangular plate shape. In this example, the closing plate portion 28 is provided so as to extend radially inward from a circumferential middle portion of a radially inner end portion of the support plate portion 27.

[0055] The cover 5 further has a protrusion 31 disposed inside the accommodating recess 13 .

[0056] In this example, the protrusion 31 is provided so as to protrude from a circumferential middle portion of a side surface on one axial side of the closing plate portion 28 toward one axial side.

[0057] As shown in Fig. 12(a) and Fig. 12(b), of a pair of outer surfaces 32a, 32b facing opposite sides in the circumferential direction of the protrusion 31, one outer surface 32a facing the opposing surface 16a of one side wall portion 15a has a shape along the opposing surface 16a. Specifically, one outer surface 32a is configured by connecting a cover-side first guide surface 33 on the radial inside and a cover-side second guide surface 34 on the radial outside by a cover-side inclined guide surface 35. The cover-side second guide surface 34 is disposed offset toward the other outer surface 32b than the cover-side first guide surface 33. In addition, the cover-side first guide surface 33 and the cover-side second guide surface 34 are disposed approximately parallel to each other. The cover-side inclined guide surface 35 is inclined in a direction approaching the other outer surface 32b as it moves toward the radial outside.

[0058] The other outer surface 32b has a shape that follows the opposing surface 16b of the other side wall portion 15b. Specifically, the other outer surface 32b is configured by connecting a cover-side first flat surface 36 on the radial inside and a cover-side second flat surface 37 on the radial outside by a step surface 38 facing radially outward. The cover-side second flat surface 37 is disposed offset toward the side closer to one outer surface 32a than the cover-side first flat surface 36. In addition, the cover-side first flat surface 36 and the cover-side second flat surface 37 are disposed approximately parallel to each other.

[0059] In this example, the convex portion 31 has protrusions 39 protruding from the other outer surface 32b. In this example, the protrusions 39 are provided at two positions on the cover-side first flat surface 36 in the radial direction.

[0060] The cover 5 is supported by the holder 4 by pressing the convex portion 31 into the accommodating recess 13. When the convex portion 31 is pressed into the accommodating recess 13, the projection 39 is pressed against the holder-side first flat surface 20 and elastically deformed. Therefore, the projection 31 is biased in a direction in which one outer side surface 32a is pressed against the opposing surface 16a of one side wall portion 15a by the force of the projection 39 attempting to elastically restore. In addition, when the cover 5 is supported by the holder 4, both circumferential side portions of the side surface on one axial side of the closing plate portion 28 are abutted against the seat surfaces 23a, 23b to close the opening on the other axial side of the accommodating recess 13.

[0061] The cover 5 is made of synthetic resin, which is a non-magnetic and non-conductive (insulating) material. Specifically, the cover 5 is made of thermoplastic resin such as epoxy resin, polyphenylene sulfide (PPS), PA (polyamide), and PPA (polyphthalamide). In this example, the cover 5 is integrally formed as a whole by injection molding of synthetic resin.

[0062] The flexible substrate 6 has a detection section 41 having a plurality of detection coils 40a-40d for detecting the magnetic field of the rotating shaft 2 and arranged around the inner cylindrical portion 10 of the holder 4, and a signal line portion 43 having a plurality of signal lines 53a-53d for electrically connecting the detection section 41 to an external device 42, a portion of which is accommodated inside the accommodating recess 13.

[0063] 9, in the unfolded state of the flexible substrate 6, the detection section 41 is configured in a strip-like or rectangular plate-like shape. In addition, in the unfolded state of the flexible substrate 6, the signal line portion 43 has a protruding portion 44 protruding in the short-side direction from one long side of the detection section 41, a linear portion 45 extending in the long-side direction from the protruding portion 44, and a sensor-side contact mounting portion 80 in the shape of a trapezoidal plate provided at the tip of the linear portion 45.

[0064] The films constituting the flexible substrate 6, i.e., the cover film and / or the base film, are obtained by punching a base material using a punching die. Specifically, a plurality of films are punched out at once from one base material.

[0065] In this example, the detection unit 41 has four detection coils 40a to 40d. As shown in Fig. 7(a) to Fig. 7(d), each of the detection coils 40a to 40d is configured by arranging a plurality of coil pieces 46a to 46d, 47a to 47d in the circumferential direction (the long side direction of the detection unit 41 when the flexible substrate 6 is in the unfolded state).

[0066] Specifically, the first detection coil 40a is configured by connecting in series a plurality of coil pieces 46a, 47a arranged in the circumferential direction, the second detection coil 40b is configured by connecting in series a plurality of coil pieces 46b, 47b arranged in the circumferential direction, the third detection coil 40c is configured by connecting in series a plurality of coil pieces 46c, 47c arranged in the circumferential direction, and the fourth detection coil 40d is configured by connecting in series a plurality of coil pieces 46d, 47d arranged in the circumferential direction.

[0067] Of the coil pieces 46a to 46d, 47a to 47d, the coil pieces 46a to 46d located at both ends in the circumferential direction are configured by arranging the wiring pattern so as to wind around the coil in an approximately triangular shape when viewed from the radial direction, and the remaining coil pieces 47a to 47d are configured by arranging the wiring pattern so as to wind around the coil in an approximately parallelogram shape when viewed from the radial direction.

[0068] The coil pieces 46a, 47a constituting the first detection coil 40a and the coil pieces 46c, 47c constituting the third detection coil 40c have straight line portions inclined at a predetermined angle (for example, +45 degrees) in a predetermined direction with respect to the axial direction of the rotation shaft 2 (the direction of the short side of the detection section 41 when the flexible substrate 6 is in the unfolded state). The coil pieces 46b, 47b constituting the second detection coil 40b and the coil pieces 46d, 47d constituting the fourth detection coil 40d have straight line portions inclined at a predetermined angle (for example, -45 degrees) in a direction opposite to the predetermined direction with respect to the axial direction of the rotation shaft 2.

[0069] The four detection coils 40a to 40d are arranged overlapping each other in the radial direction. Specifically, from the outside in the radial direction, the first detection coil 40a, the second detection coil 40b, the third detection coil 40c, and the fourth detection coil 40d are arranged in this order.

[0070] For this reason, in this example, flexible substrate 6 has a multi-layer structure having a plurality of wiring layers 48a to 48d.

[0071] In this example, the flexible substrate 6 has four wiring layers 48a to 48d. Specifically, as shown in Fig. 6, the flexible substrate 6 is configured by laminating, in order from the radially outer side, a first coverlay film 49a, a first adhesive layer 50a, a first wiring layer 48a, a first base film 51a, a second wiring layer 48b, a second adhesive layer 50b, a second coverlay film 49b, a double-sided tape 52, a third coverlay film 49c, a third adhesive layer 50c, a third wiring layer 48c, a second base film 51b, a fourth wiring layer 48d, a fourth adhesive layer 50d, and a fourth coverlay film 49d.

[0072] Each of the coverlay films 49a to 49d and the base films 51a and 51b is formed in a thin film shape from an insulating material such as polyimide, polyester, etc. The coverlay films 49a to 49d are protective films for protecting the wiring layers 48a to 48d.

[0073] Each of the wiring layers 48a to 48d is composed of a wiring pattern formed by etching copper foil. The first wiring layer 48a is formed on the radial outer surface of the first base film 51a, and the second wiring layer 48b is formed on the radial inner surface of the first base film 51a. The third wiring layer 48c is formed on the radial outer surface of the second base film 51b, and the fourth wiring layer 48d is formed on the radial inner surface of the second base film 51b.

[0074] Each of the adhesive layers 50a to 50d is made of an adhesive that bonds the coverlay films 49a to 49d, the wiring layers 48a to 48d, and the base films 51a and 51b to one another. Specifically, each of the adhesive layers 50a to 50d is made of an epoxy resin-based or acrylic resin-based adhesive.

[0075] The double-sided tape 52 bonds the second coverlay film 49b and the third coverlay film 49c together.

[0076] In this example, the first detect coil 40a is formed in the first wiring layer 48a, the second detect coil 40b is formed in the second wiring layer 48b, the third detect coil 40c is formed in the third wiring layer 48c, and the fourth detect coil 40d is formed in the fourth wiring layer 48d.

[0077] The detection coils 40a to 40d that constitute the detection unit 41 are electrically connected to the external device 42 by signal lines 53a to 53d and a connector 7 provided on the signal line section 43, a cable connected to the external device 42, and a device-side connector provided at the tip of the cable.

[0078] In this example, the signal line portion 43 has four signal lines 53a to 53d (see FIG. 8).

[0079] Of the four signal lines 53a to 53d, the first signal line 53a connects one end of the first detection coil 40a and one end of the second detection coil 40b in series, and is connected to a first sensor-side contact provided in the connector 7. The first sensor-side contact is engageable with a first device-side contact provided in the device-side connector. The first device-side contact is electrically connected to one terminal of an oscillator 54 constituting the external device 42 via the cable.

[0080] The second signal line 53b connects one end of the third detection coil 40c and one end of the fourth detection coil 40d in series, and is connected to a second sensor-side contact provided in the connector 7. The second sensor-side contact is engageable with a second device-side contact provided in the device-side connector. The second device-side contact is electrically connected to the other terminal of the oscillator 54 via the cable.

[0081] The third signal line 53c connects the other end of the first detection coil 40a and the other end of the third detection coil 40c in series, and is connected to a third sensor-side contact provided in the connector 7. The third sensor-side contact is engageable with a third device-side contact provided in the device-side connector. The third device-side contact is electrically connected to one terminal of a voltmeter 55 constituting the external device 42 via the cable.

[0082] The fourth signal line 53d connects the other end of the second detection coil 40b and the other end of the fourth detection coil 40d in series, and is connected to a fourth sensor-side contact provided in the connector 7. The fourth sensor-side contact is engageable with a fourth device-side contact provided in the device-side connector. The fourth device-side contact is electrically connected to the other terminal of the voltmeter 55 via the cable.

[0083] Each contact is mounted on a sensor-side contact mounting section 80. The sensor-side contact mounting section 80 is accommodated inside the connector 7. Each contact is composed of a socket, a pin, or the like.

[0084] When the connector 7 and the device-side connector are connected, a bridge circuit including the four detection coils 40a to 40d, the oscillator 54, and the voltmeter 55 is formed.

[0085] The oscillator 54 applies an AC voltage between a contact A between one end of the first detection coil 40a and one end of the second detection coil 40b, and a contact B between one end of the third detection coil 40c and one end of the fourth detection coil 40d. The voltmeter 55 detects a voltage between a contact C between the other end of the first detection coil 40a and the other end of the third detection coil 40c, and a contact D between the other end of the second detection coil 40b and the other end of the fourth detection coil 40d.

[0086] When torque T is applied to the rotating shaft 2, stresses σ with opposite signs (+ and -) act on the outer circumferential surface of the rotating shaft 2 in a direction inclined at +45° with respect to the axial direction and in a direction inclined at -45° with respect to the axial direction. Due to the inverse magnetostrictive effect, the magnetic permeability increases in the direction in which tensile stress (+σ) acts, and decreases in the direction in which compressive stress (-σ) acts. In the magnetostrictive torque sensor 1 of this example, the voltage of the bridge circuit, which changes with the change in magnetic permeability of the rotating shaft 2, is detected by a voltmeter 55, and the direction and magnitude of the torque transmitted by the rotating shaft 2 are determined based on the detected value.

[0087] The signal lines 53a to 53d are configured by wiring patterns formed on the wiring layers 48a to 48d of the signal line portion 43.

[0088] The signal line portion 43 is led out through the accommodating recess 13 into the external space.

[0089] In this example, the connection portion between the protrusion 44 of the signal line portion 43 and the linear portion 45 is bent at approximately a right angle, the base end of the linear portion 45, i.e., the radially inner end, is positioned inside the accommodating recess 13, and the tip portion of the linear portion 45, i.e., the radially outer portion, is pulled out into the outer space.

[0090] According to this embodiment, since the connection portion between the protruding portion 44 and the linear portion 45 is bent at a substantially right angle, it is possible to prevent the detection portion 41 from rising up from the inner cylindrical portion 10 .

[0091] In other words, when the flexible board is bent at the connection between the detection section and the signal line section, the force of the bent part attempting to elastically restore itself may act on the detection section, causing it to lift up from the inner tube portion of the holder.

[0092] In contrast, in the present example, the connection portion between the protrusion 44 protruding in the short side direction from one long side of the detection portion 41 and the linear portion 45 extending in the long side direction from the protrusion 44 is bent at approximately a right angle, so that it is possible to prevent a force acting on the detection portion 41 to cause it to lift up from the inner tube portion 10 of the holder 4 based on the force of the bent portion attempting to elastically restore its original shape.

[0093] In this example, the base end of the linear portion 45 extends in a direction substantially perpendicular to the inner tubular portion 10 and the outer tubular portion 12 of the holder 4. Therefore, even if a pulling force is applied to the tip end portion of the linear portion 45, it is possible to prevent a force that rotates the holder 4 from being applied to the holder 4.

[0094] Further, the base end of the linear portion 45 is sandwiched inside the accommodating recess 13 between the opposing surface 16 a of one side wall portion 15 a and one outer surface 32 a of the protruding portion 31 .

[0095] In particular, in this example, when the protrusion 31 is pressed into the accommodating recess 13, the force of the protrusion 39 provided on the other outer surface 32b of the protrusion 31 to elastically restore is applied to the protrusion 31 in a direction in which the one outer surface 32a is pressed against the opposing surface 16a of the one side wall portion 15a. Therefore, the base end of the linear portion 45 is tightly sandwiched between the opposing surface 16a of the one side wall portion 15a and the one outer surface 32a of the protrusion 31. Therefore, even if a pulling force is applied to the tip end portion of the linear portion 45, the force can prevent the detection portion 41 from being pulled radially outward and lifting up from the inner tube portion 10.

[0096] In this example, the linear portion 45 is curved in a substantially crank shape between the opposing surface 16a of one side wall portion 15a and one outer surface 32a of the protrusion 31 along the opposing surface 16a and the outer surface 32a. Therefore, when a pulling force is applied to the tip end portion of the linear portion 45, the linear portion 45 is pressed against the connection portion between the holder side second guide surface 18 and the holder side inclined guide surface 19 of the opposing surface 16a and the connection portion between the cover side first guide surface 33 and the cover side inclined guide surface 35 of the outer surface 32a, and the contact surface pressure with these contact portions increases. With such an increase in contact surface pressure, the frictional resistance acting between the linear portion 45 and the opposing surface 16a and the outer surface 32a increases. As a result, the detection portion 41 is pulled radially outward, and thus it is possible to prevent the detection portion 41 from floating up from the inner tube portion 10.

[0097] That is, in this example, the connection portion of the opposing surface 16a between the holder-side second guide surface 18 and the holder-side inclined guide surface 19, and the connection portion of the outer surface 32a between the cover-side first guide surface 33 and the cover-side inclined guide surface 35 correspond to the convex corner portion. Also, the connection portion of the outer surface 32a between the cover-side second guide surface 34 and the cover-side inclined guide surface 35, and the connection portion of the opposing surface 16a between the holder-side first guide surface 17 and the holder-side inclined guide surface 19 correspond to the concave corner portion.

[0098] When implementing the magnetostrictive torque sensor of the present disclosure, the shapes of the opposing surface 16a and the outer surface 32a that sandwich the linear portion 45 can be changed as appropriate as long as the detection portion 41 can be prevented from floating up from the inner cylindrical portion 10.

[0099] For example, in a first example of the modified example shown in FIG. 14(a), a small convex portion 56 is provided on the cover-side first guide surface 33 of the outer side surface 32a, and a small concave portion 57 is provided on the holder-side first guide surface 17 of the opposing surface 16a. In this modified example, when a force in the pulling direction is applied to the tip side portion of the linear portion 45, the linear portion 45 is pressed against the small convex portion 56 in addition to the connection portion between the holder-side second guide surface 18 and the holder-side inclined guide surface 19 of the opposing surface 16a and the connection portion between the cover-side first guide surface 33 and the cover-side inclined guide surface 35 of the outer side surface 32a. As a result, the contact surface pressure between these contact portions and the small convex portion 56 and the linear portion 45 increases, preventing the detection portion 41 from floating up from the inner tube portion 10.

[0100] In this modification, the connection between the holder-side second guide surface 18 and the holder-side inclined guide surface 19, the connection between the cover-side first guide surface 33 and the cover-side inclined guide surface 35, and the small convex portion 56 each correspond to a convex corner portion. Also, the connection between the cover-side second guide surface 34 and the cover-side inclined guide surface 35, the connection between the holder-side first guide surface 17 and the holder-side inclined guide surface 19, and the small concave portion 57 each correspond to a concave corner portion.

[0101] It is also possible to provide a plurality of small protrusions and small recesses. Also, a small protrusion may be provided on the opposing surface of one of the side walls, and a small recess may be provided on one of the outer surfaces.

[0102] 14(b), the opposing surface 16a of one side wall portion 15a is configured by connecting the radially inner holder-side first guide surface 17 and the radially outer holder-side second guide surface 18 by a holder-side step surface 58 facing radially inward. Also, one outer surface 32a is configured by connecting the radially inner cover-side first guide surface 33 and the radially outer cover-side second guide surface 34 by a cover-side step surface 59 facing radially outward.

[0103] In this modification, when a pulling force is applied to the tip end portion of the linear portion 45, the linear portion 45 is pressed against a connection portion of the opposing surface 16a between the holder side second guide surface 18 and the holder side step surface 58, and a connection portion of the outer surface 32a between the cover side first guide surface 33 and the cover side step surface 59. As a result, the surface pressure between these contact portions and the linear portion 45 increases, preventing the detection portion 41 from floating up from the inner tube portion 10.

[0104] In this modification, the connection between the holder-side second guide surface 18 and the holder-side step surface 58, and the connection between the cover-side first guide surface 33 and the cover-side step surface 59 correspond to convex corners. The connection between the cover-side second guide surface 34 and the cover-side step surface 59, and the connection between the holder-side first guide surface 17 and the holder-side step surface 58 correspond to concave corners.

[0105] 14(c), the opposing surface 16a of one side wall portion 15a and one outer surface 32a of the protrusion 31 are each configured in a stepped shape. Specifically, the opposing surface 16a has, in order from the radially inner side, a holder-side first guide surface 60, a holder-side first step surface 61, a holder-side second guide surface 62, a holder-side second step surface 63, and a holder-side third guide surface 64.

[0106] The holder-side second guide surface 62 is offset from the holder-side first guide surface 60 toward the other side wall portion 15b, and the holder-side third guide surface 64 is offset from the holder-side first guide surface 60 toward the other side wall portion 15b. The holder-side first guide surface 60, the holder-side second guide surface 62, and the holder-side third guide surface 64 are disposed substantially parallel to each other. The holder-side first guide surface 60 and the holder-side second guide surface 62 are connected by a holder-side first step surface 61 facing radially inward, and the holder-side second guide surface 62 and the holder-side third guide surface 64 are connected by a holder-side second step surface 63 facing radially inward.

[0107] The outer surface 32a has, in order from the radially inner side, a cover side first guide surface 65, a cover side first step surface 66, a cover side second guide surface 67, a cover side second step surface 68, and a cover side third guide surface 69.

[0108] The cover-side second guide surface 67 is offset from the cover-side first guide surface 65 toward one outer side surface 32b, and the cover-side third guide surface 69 is offset from the cover-side second guide surface 67 toward the other side wall portion 15b. The cover-side first guide surface 65, the cover-side second guide surface 67, and the cover-side third guide surface 69 are disposed substantially parallel to each other. The cover-side first guide surface 65 and the cover-side second guide surface 67 are connected by a cover-side first step surface 66 facing radially outward, and the cover-side second guide surface 67 and the cover-side third guide surface 69 are connected by a cover-side second step surface 68 facing radially outward.

[0109] In this modification, when a pulling force is applied to the tip end portion of the linear portion 45, the linear portion 45 is pressed against the connection portion of the opposing surface 16a between the holder side third guide surface 64 and the holder side second step surface 63, the connection portion of the holder side second guide surface 62 and the holder side first step surface 61, the connection portion of the outer surface 32a between the cover side second step surface 68 and the cover side second guide surface 67, and the connection portion of the cover side first step surface 66 and the cover side first guide surface 65. As a result, the contact surface pressure between these contact portions and the linear portion 45 increases, and the detection portion 41 is prevented from floating up from the inner tube portion 10.

[0110] In this modification, the connection portion between the holder-side third guide surface 64 and the holder-side second step surface 63, the connection portion between the holder-side second guide surface 62 and the holder-side first step surface 61, the connection portion between the cover-side second step surface 68 and the cover-side second guide surface 67, and the connection portion between the cover-side first step surface 66 and the cover-side first guide surface 65 correspond to convex corners. Also, the connection portion between the holder-side second step surface 63 and the holder-side second guide surface 62, the connection portion between the holder-side first step surface 61 and the holder-side first guide surface 60, the connection portion between the cover-side third guide surface 69 and the cover-side second step surface 68, and the connection portion between the cover-side second guide surface 67 and the cover-side first step surface 66 correspond to concave corners.

[0111] The connector 7 is attached to the tip of the signal line portion 43. The connector 7 and the tip of the signal line portion 43 are joined by adhesion, soldering, or the like.

[0112] In addition, the connector 7 is supported relative to the cover 5 .

[0113] In this example, the connector 7 has a connector body 78 and a supported plate portion 79 .

[0114] The connector body 78 has a socket S into which the device-side connector is plugged. On the inside of the socket S, there are provided sensor-side contacts to which the signal lines 53a to 53d are connected.

[0115] In this example, the connector body 78 is configured in a substantially rectangular columnar shape. However, when implementing the magnetostrictive torque sensor of the present disclosure, the shape of the connector body is not limited to a substantially rectangular columnar shape and may be any shape.

[0116] The supported plate portion 79 is configured in a substantially rectangular flat plate shape and is joined and fixed to one of the four side surfaces of the connector main body 78 in the axial direction.

[0117] In this example, both widthwise edge portions (both circumferential edge portions) of the supported plate portion 79 are engaged with slits 30a, 30b of the support plate portion 27 constituting the cover 5, thereby supporting the connector 7 with respect to the cover 5. In this example, with the connector 7 supported by the cover 5, the insertion port S faces radially outward.

[0118] In the magnetostrictive torque sensor 1 of this embodiment, by changing the shape of the connector 7 and / or the shape of the cover 5, the orientation of the socket S of the connector 7, that is, the connection direction of the device-side connector, can be changed.

[0119] Specifically, for example, as shown in Figures 15 and 16, slits are formed on radially opposing side surfaces of a recess provided on one axial side of the support plate portion 27, and the edge portions on both widthwise sides of the supported plate portion 79 of the connector 7 are engaged with the slits, thereby supporting the connector 7 relative to the cover 5 so that the plug port S faces in the circumferential direction.

[0120] In short, according to the present disclosure, the connection direction of the device-side connector can be appropriately changed by simply changing the shape of the connector 7 and / or the shape of the cover 5, without changing the shape of the holder 4. Therefore, it is possible to ensure good attachment of the magnetostrictive torque sensor 1 to the fixed portion 3 while suppressing an increase in the manufacturing cost of the magnetostrictive torque sensor 1.

[0121] Furthermore, according to the magnetostrictive torque sensor 1 of this embodiment, damage to the flexible substrate 6, particularly the signal line portion 43, can be prevented during the attachment work of the magnetostrictive torque sensor 1 to the fixed portion 3.

[0122] In other words, when the band-shaped signal line portion provided on the flexible board is pulled out from the holder that houses the detection portion of the flexible board, care must be taken when attaching the magnetostrictive torque sensor to the fixed part so as not to damage the signal line portion, which may reduce workability.

[0123] In contrast, in this example, the connector 7 is supported by the cover 5, which prevents damage to the signal line portion 43 during installation of the magnetostrictive torque sensor 1 to the fixed part 3, making it easier to ensure workability.

[0124] In this example, the connector 7 is supported by the cover 5. In other words, the cover 5 for closing the opening on the other axial side of the accommodating recess 13 also functions as a bracket for supporting the connector 7. Therefore, there is no need to provide a separate bracket for supporting the connector 7, and the number of parts can be reduced, which makes it easier to keep costs down.

[0125] In addition, when implementing the present disclosure, various structures can be adopted, not limited to the structure of this example, as long as the connector can be supported by the cover. Specifically, for example, the connector can be configured to be supported by a screw or the like against a supported portion of the cover.

[0126] The magnetic ring 8 is also called a back yoke and has a function of suppressing leakage of magnetic flux generated by the detection coils 40a to 40d to the outside. The magnetic ring 8 has a ring side cylindrical portion 70, a ring side fitting surface 71, and a ring side locking hole 72.

[0127] In this example, the magnetic ring 8 is composed of only a ring side cylindrical portion 70, and is configured to have a substantially cylindrical shape as a whole.

[0128] The ring side tube portion 70 is disposed around the detection portion 40. In this example, the ring side tube portion 70 has a small diameter portion 73 on the other axial side portion, and a large diameter portion 74 with an outer diameter larger than that of the small diameter portion 73 at the end portion on one axial side. That is, the ring side tube portion 70 has an outer circumferential surface in the form of a stepped cylindrical surface, in which the outer circumferential surface of the small diameter portion 73 and the outer circumferential surface of the large diameter portion 74 are connected by a step surface 75 facing the other axial side. In contrast, the inner circumferential surface of the small diameter portion 73 and the inner circumferential surface of the large diameter portion 74 are located on the same cylindrical surface. Therefore, the radial thickness of the large diameter portion 74 is thicker than the radial thickness of the small diameter portion 73.

[0129] The ring side fitting surface 71 fits without rattle with the holder side fitting surface 24. In this example, the ring side fitting surface 71 is provided on the outer peripheral surface of the large diameter portion 74. Specifically, the ring side fitting surface 71 is provided on the entire outer peripheral surface of the large diameter portion 74, and is configured as a single cylindrical surface whose outer diameter does not change in the axial direction.

[0130] In this example, the ring-side fitting surface 71 has an outer diameter dimension that is slightly smaller than the inner diameter dimension of the holder-side fitting surface 24. Therefore, when the magnetostrictive torque sensor 1 is in an assembled state, the holder-side fitting surface 24 and the ring-side fitting surface 71 are fitted together by a spigot-fit, which is a clearance fit with no radial rattle.

[0131] In the magnetostrictive torque sensor 1 of this embodiment, the holder-side mating surface 24 of the holder 4 and the ring-side mating surface 71 of the magnetic ring 8 are fitted together without any rattle. This ensures good coaxiality between the holder 4 and the magnetic ring 8, and allows a stable magnetic circuit to be formed that passes through the rotating shaft 2, the holder 4, and the magnetic ring 8.

[0132] However, when implementing the magnetostrictive torque sensor of the present disclosure, the holder side mating surface and the ring side mating surface can also be mated by press-fitting (including light press-fitting).

[0133] In this example, the axial length of the holder-side fitting surface 24 and the axial length of the ring-side fitting surface 71 are approximately the same. In other words, the axial length of the outer tubular portion 12 and the axial length of the large diameter portion 74 are approximately the same. Therefore, when the magnetostrictive torque sensor 1 is assembled, the axial position of the step surface 75 and the axial position of the end face on the other axial side of the outer tubular portion 12 are approximately the same. In other words, the step surface 75 and the end face on the other axial side of the outer tubular portion 12 are located on approximately the same plane.

[0134] However, the axial length of the outer diameter side cylindrical portion can also be made shorter or longer than the axial length of the large diameter portion.

[0135] The ring side locking holes 72 are provided so as to open to the outer circumferential surface of the large diameter portion 74, i.e., the ring side fitting surface 71. In this example, the ring side locking holes 72 are provided so as to open to five locations on the ring side fitting surface 71 that are equally spaced in the circumferential direction.

[0136] In this example, the ring-side locking hole 72 has a circular opening shape and is configured as a bottomed hole that is open only at the radially outer end. However, when implementing the magnetostrictive torque sensor of the present disclosure, the opening shape of the ring-side locking hole can be appropriately changed depending on the shape of the positioning member. In addition, the ring-side locking hole can be formed so as to penetrate the magnetic ring in the radial direction.

[0137] The magnetic ring 8 is integrally formed from a magnetic material. As the magnetic material for the magnetic ring 8, for example, an iron-based alloy such as alloy steel for machine construction or stainless steel can be used.

[0138] The positioning members 9a, 9b are fitted across the holder side locking hole 25 of the holder 4 and the ring side locking hole 72 of the magnetic ring 8. This makes it possible to reliably prevent relative displacement in the axial and circumferential directions between the holder 4 and the magnetic ring 8 even if the holder 4 and / or the magnetic ring 8 expands or contracts due to temperature changes. In other words, the magnetostrictive torque sensor 1 of this example makes it possible to ensure sufficient bonding strength between the holder 4 and the magnetic ring 8, specifically, bonding strength in the axial and circumferential directions.

[0139] The magnetostrictive torque sensor 1 of this embodiment includes five positioning members 9a, 9b.

[0140] Of the five positioning members 9a, 9b, the length of three positioning members 9a is equal to or less than the sum of the radial dimension of holder side locking hole 25 and the radial depth of ring side locking hole 72. Therefore, each of the positioning members 9a has a radially outer portion disposed (inserted) inside holder side locking hole 25 and a radially inner portion disposed (inserted) inside ring side locking hole 72. In other words, the radially outer end of the positioning member 9a does not protrude radially outward from the radially outer opening of holder side locking hole 25.

[0141] The length of the remaining two positioning members 9b is longer than the sum of the radial dimension of the holder side locking hole 25 and the radial depth of the ring side locking hole 72. Therefore, the radial middle portion of each of the positioning members 9b is disposed (inserted) inside the holder side locking hole 25, and the radial inner portion is disposed (inserted) inside the ring side locking hole 72. In other words, the radial outer end of the positioning member 9b protrudes radially outward from the radial outer opening of the holder side locking hole 25.

[0142] In this example, the positioning members 9a and 9b are formed of a partially cut cylindrical spring pin having a linear or wavy slit at one circumferential position. The positioning members 9a and 9b are inserted into the holder side locking hole 25 and the ring side locking hole 72 in a state in which the width of the slit is elastically narrowed to reduce the outer diameter, and are then elastically restored. As a result, the positioning members 9a and 9b are tightly fitted into at least one of the holder side locking hole 25 and the ring side locking hole 72, and are bridged between the holder side locking hole 25 and the ring side locking hole 72.

[0143] When implementing the magnetostrictive torque sensor of the present disclosure, the positioning member is not particularly limited as long as it can prevent relative displacement between the holder and the magnetic ring. For example, the positioning member can be configured with a columnar or cylindrical pin. The cross-sectional shape of the positioning member is not limited to a circle, and can be a non-circular shape such as a partially cut circle or a polygon. Alternatively, the positioning member can be configured with a screw. In this case, the ring-side locking hole provided in the magnetic ring is a screw hole.

[0144] In this example, the positioning members 9a and 9b are made of a metal material such as an iron alloy or a light alloy, but the material constituting the positioning members is not particularly limited as long as it can ensure sufficient bonding strength between the holder and the magnetic ring, and synthetic resins, etc., can also be used.

[0145] The magnetostrictive torque sensor 1 is supported and fixed to the fixed part 3 in a state where rotation with respect to the fixed part 3 is prevented by fitting the outer tubular portion 12 of the holder 4 without rattle into a fixed-side fitting surface 76 provided on the inner circumferential surface of the fixed part 3 and arranging the radially outer ends of the two positioning members 9b inside locking recesses 77 formed in the fixed-side fitting surface 76. With the magnetostrictive torque sensor 1 supported and fixed to the fixed part 3, the magnetostrictive torque sensor 1 is arranged around the rotating shaft 2. In other words, the magnetostrictive torque sensor 1 is supported and fixed to the fixed part 3 with the rotating shaft 2 inserted inside the inner tubular portion 10.

[0146] In this example, with the magnetostrictive torque sensor 1 supported and fixed to the fixed portion 3, a part of the fixed portion 3 abuts against or faces closely to the radially outer ends of the positioning members 9a, 9b, thereby preventing the positioning members 9a, 9b from coming off. [Explanation of symbols]

[0147] 1. Magnetostrictive torque sensor 2 Rotation Axis 3 Fixed part 4 Holder 5 Cover 6 Flexible Boards 7 Connectors 8 Magnetic Ring 9a, 9b Positioning members 10 Inner cylinder part 11 Side plate part 12 Outer cylinder part 13 Recessed portion 14 Bottom plate part 15a, 15b side wall part 16a, 16b Opposite surface 17 First guide surface on holder side 18 Second guide surface on holder side 19. Holder side inclined guide surface 20 First flat surface on holder side 21 Second flat surface on holder side 22 Step surface 23a, 23b Pedestal surface 24 Holder side mating surface 25 Holder side locking hole 26 Connector support 27 Support plate part 28 Closing plate 29 Recess 30a, 30b slit 31 Convex 32a, 32b outer surface 33 Cover side first guide surface 34 Cover side second guide surface 35 Cover side inclined guide surface 36 Cover side first flat surface 37 Second flat surface on cover side 38 Step surface 39 Protrusion 40a First detection coil 40b Second detection coil 40c Third detection coil 40d Fourth detection coil 41 Detection unit 42 External device 43 Signal line section 44 Protrusion 45 Linear section 46a~46d Coil pieces 47a~47d Coil pieces 48a First wiring layer 48b Second wiring layer 48c 3rd wiring layer 48d 4th wiring layer 49a First coverlay film 49b Second Coverlay Film 49c Third Coverlay Film 49d 4th Coverlay Film 50a First adhesive layer 50b Second adhesive layer 50c Third adhesive layer 50d 4th adhesive layer 51a First base film 51b Second base film 52 Double-sided tape 53a First signal line 53b Second signal line 53c Third signal line 53d 4th signal line 54 Oscillator 55 Voltmeter 56 Small protrusion 57 Small recess 58 Holder side step surface 59 Cover side step surface 60 First guide surface on holder side 61 First step surface on holder side 62 Holder side second guide surface 63 Second step surface on holder side 64 Holder side third guide surface 65 Cover side first guide surface 66 Cover side first step surface 67 Cover side second guide surface 68 Cover side second step surface 69 Cover side third guide surface 70 Ring side cylinder 71 Ring side mating surface 72 Ring side locking hole 73 Small diameter section 74 Large diameter section 75 Step surface 76 Fixed side mating surface 77 Locking recess 78 Connector body 79 Supported plate part 80 Sensor side contact mounting part

Claims

1. A magnetostrictive torque sensor for measuring a torque applied to a rotating shaft having magnetostrictive properties, a holder including an inner cylindrical portion disposed around the rotating shaft, a side plate portion bent radially outward from one axial end of the inner cylindrical portion, an outer cylindrical portion bent from a radially outer end of the side plate portion toward the other axial side, and an accommodating recess that communicates an inner space present radially inside the outer cylindrical portion with an outer space present radially outside the outer cylindrical portion and that is open on the other axial side; a cover that closes an opening on the other axial side of the accommodating recess; a flexible substrate including a detection section including a plurality of detection coils and disposed around the inner cylindrical section, and a signal line section including a plurality of signal lines electrically connected to the plurality of detection coils, a portion of which is accommodated inside the accommodation recess; a connector attached to a tip end of the signal line portion; Equipped with The cover has a connector support portion for supporting the connector. Magnetostrictive torque sensor.

2. 2. The magnetostrictive torque sensor according to claim 1, wherein the cover has a support plate portion including the connector support portion, and a closing plate portion closing an opening on the other axial side of the accommodating recess.

3. The connector support portion is configured by a slit, The magnetostrictive torque sensor according to claim 1 , wherein the connector is supported on the cover by engaging a portion of the connector with the slit.

4. the cover has a protrusion disposed inside the accommodating recess, one of the accommodating recess and the protruding portion has a convex corner that increases a contact surface pressure with the signal line portion when the signal line portion is pulled toward the outer space, 2. The magnetostrictive torque sensor according to claim 1, wherein the other of the accommodating recess and the protruding portion has a recessed corner portion facing the protruding corner portion.

5. The magnetostrictive torque sensor according to claim 1 , further comprising a magnetic ring disposed around the detection portion.

6. The holder has a cylindrical holder-side fitting surface and a holder-side locking hole, the magnetic ring has a ring-side mating surface that mates with the holder-side mating surface and a ring-side locking hole, 6. The magnetostrictive torque sensor according to claim 5, further comprising a positioning member extending between the holder-side locking hole and the ring-side locking hole.

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