JP6350233B2 - Vehicle detection device - Google Patents

Description

  The present invention relates to a vehicle detection device that detects torque applied to a rotating shaft of a vehicle and the number of rotations of the rotating shaft.

  Conventionally, a vehicle detection device that detects torque applied to a steering shaft (rotating shaft) of a vehicle and the number of rotations of the steering shaft has been proposed (see, for example, Patent Document 1).

  The vehicle detection device includes a torque sensor (torque detection unit) that magnetically detects torque applied to the steering shaft, and an index sensor (rotation detection unit) that magnetically detects the rotation speed of the steering shaft.

The torque sensor includes an annular first magnet portion disposed so as to surround the periphery of the steering shaft, and a first magnetic sensor disposed on the side of the first magnet portion, and the torsion incorporated in the steering shaft. The torsion angle of the bar is detected as a change in magnetic flux density formed by the first magnet unit.
The index sensor includes a cylindrical collar attached to the steering shaft, a yoke arranged in close contact with the outer periphery of the collar so as to rotate integrally with the steering shaft, and a side of the yoke along the circumferential direction of the collar. A second magnet unit including a pair of index sensor magnets; and a second magnetic sensor disposed between the pair of index sensor magnets. Both of the pair of index sensor magnets are arranged such that the second magnetic sensor side faces the N pole. The index sensor detects rotation of the steering shaft as a change in magnetic flux density formed by the second magnet unit.
In the vehicle detection device, the direction of the magnetic flux radiated from the second magnet unit is different from the detection direction of the first magnetic sensor between the second magnet unit of the index sensor and the first magnetic sensor of the torque sensor. A magnetic plate to be changed is arranged. This magnetic plate suppresses the magnetic flux radiated from the second magnet part from interfering with the first magnetic sensor of the torque sensor and lowering the detection accuracy of the torque sensor.

JP 2010-237082 A

  However, in the conventional vehicle detection device, the annular first magnet portion of the torque sensor is arranged so as to surround the periphery of the steering shaft, and the cylindrical collar in which the second magnet portion of the index sensor is attached to the steering shaft. Therefore, if the distance between the index sensor and the torque sensor is short, the detection accuracy of the torque sensor may be affected depending on the strength of the magnetic field of the index sensor magnet. In this case, for example, by separating the index sensor from the torque sensor, the interference of magnetic flux from the index sensor to the torque sensor can be reduced, but the size of the apparatus is increased.

  Therefore, the present invention can be downsized, and the torque and steering shaft applied to the steering shaft (rotating shaft) with high accuracy without considering the interference of magnetic flux between the magnet of the rotation detecting unit and the magnet of the torque detecting unit. An object of the present invention is to provide a vehicle detection device that can detect the rotational position of the vehicle.

  In order to solve the above-mentioned problems, the present invention combines a first rotating shaft and a second rotating shaft, and transmits between the first rotating shaft and the second rotating shaft. A shaft-like elastic member that is twisted according to torque, an annular magnet that is provided so as to rotate together with the first rotating shaft, and the first rotating shaft and the magnet that rotate together. A first soft core is disposed on the outer peripheral surface of the magnet so as to be magnetically coupled to the magnetic pole, and is provided so as to extend from one end surface of the magnet along the axial direction of the first rotating shaft. The magnetic member rotates with the first rotating shaft and the magnet, and is disposed on the outer peripheral surface of the magnet so as to be magnetically coupled to the other magnetic pole of the magnet. A second soft magnetic member provided so as to extend along the axial direction of the first rotation shaft; A third soft magnetic member provided to rotate together with the second rotating shaft and disposed with a predetermined gap so as to be magnetically coupled to the first and second soft magnetic members; A fourth soft magnetic member that is magnetically coupled with a predetermined gap so that the magnetic resistance does not change with respect to the first soft magnetic member, and a magnetic resistance with respect to the rotating second soft magnetic member. A fifth soft magnetic member magnetically coupled with a predetermined gap so as not to change, a magnetic detection element for detecting a magnetic flux density generated between the fourth and fifth soft magnetic members, and There is provided a vehicle detection device including a rotation detection unit that is disposed on a side and detects a rotation angle of the first rotation shaft by detecting a magnetic flux density that changes as the magnet rotates.

  According to the vehicle detection apparatus of the present invention, the steering shaft (rotating shaft) can be miniaturized and the steering shaft (rotating shaft) with high accuracy without considering interference of magnetic flux between the magnet of the rotation detecting unit and the magnet of the torque detecting unit. And the rotational position of the steering shaft can be detected.

It is a perspective view which shows the external appearance structure of the detection apparatus 1 for vehicles which concerns on this Embodiment. It is a figure which shows the structural example of the detection apparatus 1 for vehicles which concerns on this embodiment, and is sectional drawing of the AA line (two-dot chain line) of FIG. FIG. 3 is an exploded perspective view showing a configuration example of a magnetic circuit in the vehicle detection device 1. It is a figure for demonstrating operation | movement of the detection apparatus 1 for vehicles, is a perspective view which shows the state which twisted generate | occur | produced in the torsion bar 13, and respond | corresponds to FIG. It is a figure which shows the positional relationship of the 1st to 4th yokes 21-24 of FIG. 1, and the 5th and 6th yokes 25 and 26. FIG. It is a figure which shows the positional relationship of the 1st-4th yokes 21-24 of FIG. 4, and the 5th and 6th yokes 25 and 26. FIG.

[Embodiment]
FIG. 1 is a perspective view showing an external configuration of a vehicle detection apparatus 1 according to the present embodiment. In FIG. 1, the members that hold the respective components, the steering shaft, and the like are not shown. FIG. 2 is a diagram illustrating a configuration example of the vehicle detection device 1 according to this embodiment, and is a cross-sectional view taken along the line AA (two-dot chain line) in FIG. 1. In the following description, a direction parallel to the steering shaft is referred to as an axial direction A, and a direction orthogonal to the steering shaft is referred to as a radial direction B.

  The vehicle detection device 1 magnetically detects the rotation of the steering shaft 10 and the torque detection unit 2 that magnetically detects a steering torque applied to the steering shaft 10 as a rotation shaft that is rotated by a steering operation of the steering wheel. A rotation detector 3; The vehicle detection device 1 is mounted on a vehicle, for example, and is used to detect the steering torque applied to the steering wheel by the driver and the rotation speed of the steering shaft (the direction of the wheels). The vehicle steering system is provided with an electric power steering device that assists the steering operation, and the electric power steering device is electrically driven according to the steering torque detected by the vehicle detection device 1 and the rotation speed of the steering shaft (the direction of the wheels). The motor outputs assist torque for turning the steered wheel (front wheel).

  The steering shaft 10 is connected to a steering wheel, and an input shaft 11 serving as a first rotating shaft to which a steering force is input, an output shaft 12 serving as a second rotating shaft connected to the electric power steering device side, A torsion bar 13 serving as an elastic member for connecting the input shaft 11 and the output shaft 12 is provided, and is rotatably supported inside a column housing (not shown). The input shaft 11, the output shaft 12, and the torsion bar 13 are made of a magnetic material such as an iron-based metal. The torsion bar 13 has one end on the steering wheel side fixed to the input shaft 11 by a pin 14 so as not to rotate relative to the torsion bar 13, and the other end fixed to the output shaft 12 by a pin 15 so as not to rotate relative to the input shaft 11.

(Configuration of torque detector 2)
The torque detection unit 2 includes a cylindrical detection magnet 20 fixed to the input shaft 11 so as to surround the input shaft 11, and a first fixed to the outer peripheral surface near the center of each magnetic pole of the detection magnet 20. The first and third yokes serving as one soft magnetic member, the second and fourth yokes 21 to 24 serving as second soft magnetic members, and the rotating first and third yokes 21 and 23 around The first guide ring 27, which is an annular fourth soft magnetic member fixed to the vehicle body side so as to surround, and the second and fourth yokes 22 and 24 that rotate, are fixed to the vehicle body side so as to surround the periphery. A second guide ring 28 serving as an annular fifth soft magnetic member, and arc-shaped second guide rings 28 spaced apart from each other with a predetermined gap at the lower end surfaces of the first and third yokes 21 and 23. A fifth yoke 25 serving as a soft magnetic member 3, and second and fourth yokes A sixth yoke 26 serving as an arc-shaped third soft magnetic member, which is spaced apart from the lower end surfaces of the flanges 22 and 24 with a predetermined gap, and first and second guide rings 27 and 28 A holding member 29 formed of a mold resin for holding the detection magnet 20 and the first to fourth yokes 21 to 24, and the first and second guide rings 27. , 28 and the magnetic detecting element 35, and a holding member 30 formed of a mold resin for holding the fifth and sixth yokes 25 and 26.

  The first and second guide rings 27 and 28 and the magnetic detection element 35 are insert-formed on the holding member 30. The holding member 30 is fixed to the vehicle body via the column housing. That is, even if the steering shaft 10 rotates, the first and second guide rings 27 and 28 and the magnetic detection element 35 do not rotate with the steering shaft 10 and the positions thereof are fixed.

  The detection magnet 20 is composed of an annular magnet fixedly attached around the input shaft 11 of the steering shaft 10. The detection magnet 20 is disposed so as to rotate integrally with the input shaft 11 of the steering shaft 10. In FIG. 1, the detection magnet 20 is constituted by a permanent magnet having a four-pole configuration in which N pole-S pole-N pole-S pole are formed along the circumferential direction of the steering shaft 10. In FIG. 2, it can be regarded as a two-pole configuration in which an N pole is formed on the right side (on the magnetic detection element 35 side) and an S pole is formed on the left side on the opposite side. For example, a ferrite magnet or a neodymium magnet can be used as the detection magnet 20.

  The first and third yokes 21 and 23 are fixed to the lower half of the outer peripheral surface near the center of the north pole of the detection magnet 20. The first and third yokes 21 and 23 rotate together with the steering shaft 10. The first and third yokes 21 and 23 extend from the lower end surface of the detection magnet 20 along the radial direction B of the steering shaft 10 so as to be magnetically coupled to the first guide ring 27, and from there It extends to the output shaft 12 side along the axial direction A of the steering shaft 10 and has a substantially U-shape extending from there along the axial center of the steering shaft 10, and from there to the axial direction A of the steering shaft 10. A first extending portion extending along the output shaft 12 side is formed. The first extending portion extending toward the output shaft 12 along the axial direction A is further divided into two branches, each having a branched portion. When the first and third yokes 21 and 23 are rotated, a predetermined gap is maintained between the first and third yokes 21 and 23 and the first guide ring 27 so that the magnetic resistance does not change due to the rotation. Is arranged.

  Similarly, the second and fourth yokes 22 and 24 are fixed to the lower half of the outer peripheral surface near the center of the south pole of the detection magnet 20. The second and fourth yokes 22 and 24 rotate together with the steering shaft 10. The second and fourth yokes 22, 24 are arranged so as not to be magnetically coupled to the first guide ring 27 from the outer peripheral surface of the detection magnet 20 along the axial direction A of the steering shaft 10. To the output shaft 12 side along the axial direction A of the steering shaft 10, and to the second guide ring 28. It is comprised by the substantially Z-shaped 2nd extension part which couple | bonds magnetically. The second extending portion extending toward the output shaft 12 along the axial direction A is further divided into two branches, each having a branched portion. When the second and fourth yokes 22 and 24 are rotated, a predetermined gap is maintained between the second and fourth yokes 22 and 24 and the second guide ring 28 so that the magnetic resistance does not change due to the rotation. Is arranged.

  On the other hand, the fifth and sixth yokes 25 and 26 are insert-molded in the holding member 31. The holding member 31 is fixedly attached around the output shaft 12 of the steering shaft 10. Accordingly, the fifth and sixth yokes 25 and 26 are arranged so as to rotate integrally with the output shaft 12 of the steering shaft 10.

  In the present embodiment, the magnetic detection element 35 is configured by using a Hall element, and is configured by a pair of elements that are arranged so that the detection directions of the magnetic flux density are opposite to each other. The magnetic detection element 35 is arranged in a pair so that the detection directions of the magnetic flux density are opposite to each other, thereby canceling the influence of the temperature characteristics of the Hall element and the detection sensitivity in the axial direction A, thereby detecting the vehicle. The detection accuracy of the device 1 is increased.

(Configuration of the rotation detection unit 3)
The rotation detection unit 3 includes the above-described detection magnet 20 and an angle magnetic detection element 36 disposed obliquely above the side of the detection magnet 20 and above the holding members 29 and 30. The Here, “side” means outward in the radial direction B.

  The angle magnetic detection element 36 detects a change in magnetic flux density caused by approaching or moving away from the magnetic pole (N pole or S pole) of the detection magnet 20 that rotates as the input shaft 11 rotates. The angle magnetic detection element 36 may be insert-molded in the holding member 30. Since the holding member 30 is fixed to the vehicle body via the column housing, even if the steering shaft 10 rotates, the angle magnetic detection element 36 does not rotate together with the steering shaft 10 and its position is fixed.

  In the angle magnetic detection element 36, the change direction of the magnetic flux density is detected as a biaxial direction, ie, a radial direction B perpendicular to the steering shaft 10 and a direction perpendicular to the radial direction B. Here, “the radial direction B” and “the direction orthogonal to the radial direction B” include errors within ± 10 ° in the respective directions. As the angle magnetic detection element 36, for example, a Hall element is used, but other elements such as an MR element, a GIG element, and a GMR element may be used.

(Configuration of magnetic circuit)
FIG. 3 is an exploded perspective view illustrating a configuration example of a magnetic circuit in the vehicle detection device 1. 3, illustration of the steering shaft 10 and the holding members 29, 30, and 31 in FIG. 2 is omitted.

  In the embodiment, the detection magnet 20 is constituted by a magnet having a four-pole configuration that is N pole-S pole-N pole-S pole along the circumferential direction of the steering shaft 10 as described above.

  The first and third yokes 21 and 23 are provided to rotate together with the input shaft 11 and the detection magnet 20. The first and third yokes 21 and 23 are outer peripheral surfaces of the detection magnet 20 and are near the center of one magnetic pole (N pole in the figure) (the boundary between the N pole and the S pole of the detection magnet 20). It is fixed to the lower half of the middle position. The first and third yokes 21 and 23 are branches that are substantially U-shaped as described above and a first extending portion extending toward the output shaft 12 along the axial direction A. It is comprised from the formed branch part 21a, 21b, 23a, 23b. The outer surfaces of the substantially U-shaped portions of the first and third yokes 21 and 23 are formed so as to face each other with a predetermined gap from the inner surface of the first guide ring 27.

  The second and fourth yokes 22 and 24 are provided to rotate together with the input shaft 11 and the detection magnet 20. The second and fourth yokes 22 and 24 are outer peripheral surfaces of the detection magnet 20 and are near the center of one magnetic pole (S pole in the figure) (the boundary between the N pole and the S pole of the detection magnet 20). It is fixed to the lower half of the middle position. As described above, the second and fourth yokes 22 and 24 have a substantially Z shape as a whole, and serve as a second extending portion extending toward the output shaft 12 along the axial direction A. The branched portions 22a, 22b, 24a, and 24b are formed. The outer peripheral surfaces of the branch portions 22a, 22b, 24a, and 24b of the second and fourth yokes 22 and 24 are formed to face each other with a predetermined gap from the inner peripheral surface of the second guide ring 28. .

  The first guide ring 27 is disposed so that the inner circumferential surface thereof faces the outer circumferential surface of the substantially U-shaped portions of the first and third yokes 21 and 23 in the axial direction A of the steering shaft 10. ing. The first guide ring 27 is formed concentrically with the torsion bar 13 as the central axis, and is arranged with a predetermined gap from the outer periphery of the substantially U-shaped portions of the first and third yokes 21 and 23. An annular portion 270, a projecting portion 271 projecting radially outward from the annular portion 270, and an extending portion 272 extending toward the second guide ring 28 from one end of the projecting portion 271 opposite to the annular portion 270. And projecting from the end of the extended portion 272 opposite to the projecting portion 271 to the outer side in the radial direction of the annular portion 270 (in the embodiment, the direction parallel to the projecting portion 271). A counter part 273 facing the counter part 283 is integrally provided.

  The second guide ring 28 is disposed such that the inner peripheral surface thereof faces the outer peripheral surfaces of the branch portions 22a, 22b, 24a, 24b of the second and fourth yokes 22, 24. The second guide ring 28 is formed concentrically with the torsion bar 13 as the central axis, and has a predetermined gap from the outer periphery of the branch portions 22a, 22b, 24a, 24b of the second and fourth yokes 22, 24. An annular portion 280 to be arranged, a protruding portion 281 protruding radially outward from the annular portion 280, and an extension extending from the one end of the protruding portion 281 opposite to the annular portion 280 toward the first guide ring 27 The first guide ring 27 of the first guide ring 27 protrudes radially outward of the annular portion 280 (in the embodiment, in a direction parallel to the protruding portion 281) from one end of the extending portion 282 opposite to the protruding portion 281. A facing portion 283 that faces the facing portion 273 is integrally provided.

  The protruding portions 271 and 281, the extending portions 272 and 282, and the opposing portions 273 and 283 of the first and second guide rings 27 and 28 are formed so as to extend outward from the annular portions 270 and 280 by punching. The rectangular portion thus formed can be easily manufactured by bending.

  The fifth yoke 25 opposes the lower surfaces of the branch portions 21a and 21b, which are the first extension portions of the first yoke 21, and has the same shape as the branch portions 21a and 21b (the inner peripheral surface and the outer peripheral surface are the same). The first arc portions 25a and 25b having the same shape) and the lower surfaces of the branch portions 22a and 22b serving as the second extending portions of the second yoke 22, respectively, and having the same shape as the branch portions 22a and 22b. The second arc portions 25c and 25d having the same inner peripheral surface and outer peripheral surface, and the first arc portions 25a and 25b and the second arc portions 25c and 25d having different inner peripheral surfaces and outer peripheral surfaces, respectively. And a third semicircular arc portion 25e having a different radius and connecting the two at the lower side.

  The sixth yoke 26 is opposed to the lower surfaces of the branch portions 23a and 23b of the third yoke 23, and has the same shape as the branch portions 23a and 23b (inner and outer peripheral surfaces are equal). The arc portions 26a and 26b are opposed to the lower surfaces of the branch portions 24a and 24b of the fourth yoke 24, respectively, and have the same shape as the branch portions 24a and 24b (the inner peripheral surface and the outer peripheral surface are the same shape). The substantially circular semicircular shapes having different radii connecting the arc portions 26c and 26d, the first arc portions 26a and 26b, and the second arc portions 26c and 26d having different inner and outer peripheral surfaces on the lower side. 3 arc portions 26e.

  The lower surfaces of the third arc portions 25e and 26e of the fifth and sixth yokes 25 and 26 are common. The arc portions 25a, 25b, 25c, 25d, 26a, 26b, 26c, and 26d of the fifth and sixth yokes 25 and 26 are formed to have the same height from the lower surface.

  Between the facing portion 273 of the first guide ring 27 and the facing portion 283 of the second guide ring 28, the magnetic detection element 35 is disposed.

  The path of the magnetic flux generated by the detection magnet 20, that is, the first to third magnetic paths M1, M2, and M3 are configured as follows. As shown by a two-dot chain line in FIG. 3, the first magnetic path M1 has N poles 20a, 20c of the detection magnet 20 → first and third yokes 21,23 → first guide ring 27 → second. The guide ring 28 → the second and fourth yokes 22 and 24 → the S pole of the detection magnet 20. The second magnetic path M2 becomes N pole 20a of the detection magnet 20 → first yoke 21 → fifth yoke 25 → second yoke 22 → S pole 20b of the detection magnet 20. The third magnetic path M3 is N pole 20c of the detection magnet 20 → third yoke 23 → sixth yoke 26 → fourth yoke 24 → S pole 20d of the detection magnet 20. In the embodiment, of the magnetic flux emitted from the N pole of the detection magnet 20, the magnetic flux entering the S pole of the detection magnet 20 without passing through the magnetic paths M1, M2, and M3 is negligible. small.

(Operation of vehicle detection device)
FIG. 4 is a diagram for explaining the operation of the vehicular detection apparatus 1, is a perspective view showing a state in which the torsion bar 13 is twisted, and corresponds to FIG. 1. On the other hand, FIG. 1 shows a state where the torsion bar 13 is not twisted. Also in FIG. 4, illustrations of members that hold each component, steering shaft, and the like are omitted.

  When the steering shaft 10 is rotationally steered, torque acts on the input shaft 11 and the torsion bar 13 is twisted. Then, the detection magnet 20 and the first to fourth yokes 21 to 24 rotate in accordance with the rotationally steered rotational direction. On the other hand, the fifth and sixth yokes 25 and 26 rotate with a delay due to the twist generated in the torsion bar 13, so that the rotational positions thereof are the first to fourth yokes 21 to 21, as shown in FIG. 24 is displaced relative to 24.

  5A and 5B are views showing the positional relationship between the first to fourth yokes 21 to 24 of FIGS. 1 and 4 and the fifth and sixth yokes 25 and 26, and other components are shown. It is abbreviated. As shown in FIG. 5A, in a state where the torsion bar 13 is not twisted, the lower surfaces of the branch portions 21a, 21b, 23a, 23b of the first and third yokes 21, 23 and the fifth and sixth Of the first and second arcs 25a, 25b, 26a, and 26b of the yokes 25 and 26, and the branch portions 22a, 22b, 24a, and 24b of the second and fourth yokes 22 and 24, respectively. And the upper surfaces of the second arc portions 25c, 25d, 26c, and 26d of the fifth and sixth yokes 25 and 26 are opposed to each other. When the torsion bar 13 is twisted and the fifth and sixth yokes 25 and 26 are displaced relative to the first to fourth yokes 21 to 24, as shown in FIG. And the lower surfaces of the branch portions 21a, 21b, 23a, and 23b of the third yokes 21 and 23 and the upper surfaces of the first arc portions 25a, 25b, 26a, and 26b of the fifth and sixth yokes 25 and 26, respectively. The opposing areas, and the lower surfaces of the branch portions 22a, 22b, 24a, 24b of the second and fourth yokes 22, 24 and the second arc portions 25c, 25d of the fifth and sixth yokes 25, 26, The areas facing the upper surfaces of 26c and 26d are reduced.

  Thus, in the magnetic paths M2 and M3, the magnetic flux supplied from the north pole of the detection magnet 20 to the fifth and sixth yokes 25 and 26 via the first and third yokes 21 and 23 is reduced. The magnetic flux density decreases rapidly. On the other hand, the magnetic flux density of the magnetic flux supplied from the north pole of the detection magnet 20 to the first guide ring 27 via the first and third yokes 21 and 23 in the magnetic path M1 is accordingly increased. It becomes high rapidly. Therefore, the magnetic detection element 35 detects the twisting amount of the torsion bar 13, that is, the steering force (steering torque) transmitted from the input shaft 11 to the output shaft 12 as the amount of change in the magnetic flux density passing through the magnetic path M1. Is possible.

(Operation and effect of the embodiment)
According to the embodiment described above, the following operations and effects can be obtained.

(1) Since the magnetic detection element 35 is arranged in series with respect to the magnetic path M1, and is arranged in parallel with respect to the magnetic paths M2 and M3, the magnitude of the magnetic flux detected by the magnetic detection element 35. The lower surfaces of the branch portions 21a, 21b, 23a, and 23b of the first and third yokes 21 and 23 and the first arc portions 25a, 25b, 26a, and 26b of the fifth and sixth yokes 25 and 26, respectively. Areas facing the upper surfaces, and lower surfaces of the branch portions 22a, 22b, 24a, 24b of the second and fourth yokes 22, 24 and second arc portions of the fifth and sixth yokes 25, 26, respectively. The upper surfaces of 25c, 25d, 26c, and 26d are dependent on the size of the areas facing each other. Thereby, the magnetic detection element 35 can detect the change amount of the magnetic flux with high accuracy in accordance with the torque amount acting on the input shaft 11.

(2) Since the magnetic detection element 35 is arranged in series with respect to the magnetic path M1, and is arranged in parallel with respect to the magnetic paths M2 and M3, the first and third yokes 21, 23 and Even when the magnetoresistance between the fifth yoke and the magnetoresistance between the second and fourth yokes 22 and 24 and the sixth yoke changes, the magnetic paths M1, M2, and M3 flow through. Since the magnetic flux density is hardly changed, the influence on the angle magnetic detection element 36 can be suppressed.

(3) Since the rotation detection unit 3 can be disposed close to the torque detection unit 2, the vehicle detection device 1 can be downsized.

(Summary of embodiment)
Next, the technical idea grasped from the embodiment described above will be described with reference to the reference numerals in the embodiment. However, the reference numerals and the like in the following description are not intended to limit the constituent elements in the claims to the members and the like specifically shown in the embodiments.

[1] The first rotating shaft (11) and the second rotating shaft (12) are coupled and transmitted between the first rotating shaft (11) and the second rotating shaft (12). A shaft-like elastic member (13) that is twisted according to the torque to be rotated, an annular magnet (20) that is provided so as to rotate together with the first rotating shaft (11), and the first rotating shaft (11 ) And the magnet (20), and is disposed on the outer peripheral surface of the magnet (20) so as to be magnetically coupled to one magnetic pole (N pole) of the magnet (20). ) And a first soft magnetic member (21, 23) provided so as to extend along the axial direction of the first rotating shaft (11), and the first rotating shaft (11). And rotating together with the magnet (20) so as to be magnetically coupled to the other magnetic pole (S pole) of the magnet (20). A second soft magnetic member disposed on the outer peripheral surface of the stone (20) and provided so as to extend from one end surface of the magnet (20) along the axial direction of the first rotation shaft (11). 22, 24) and the second rotating shaft (12) so as to rotate and are magnetically coupled to the first and second soft magnetic members (21, 22, 23, 24). Thus, the third soft magnetic member (25, 26) arranged with a predetermined gap and the first soft magnetic member (21, 23) rotating with a predetermined gap so that the magnetic resistance does not change. The fourth soft magnetic member (27) to be magnetically coupled and the second soft magnetic member (22, 24) to be rotated are magnetically coupled with a predetermined gap so that the magnetic resistance does not change. Fifth soft magnetic member (28) and the fourth and fifth soft magnetic members 27, 28) A magnetic detection element (35) for detecting a magnetic flux density generated between the magnet and the magnet (20), and detecting a magnetic flux density that changes as the magnet (20) rotates. And a rotation detector (36) for detecting a rotation angle of the first rotating shaft (11).

[2] An inner peripheral surface of the first soft magnetic member (21, 23) is fixed to an outer peripheral surface of the magnet (20), and the first rotating shaft extends from one end surface of the magnet (20). The first soft magnetic members (22, 24) include first extending portions (21a, 21b, 23a, 23b) extending toward the second rotating shaft (12) along the axial direction. The inner peripheral surface of the magnet (20) is fixed to the outer peripheral surface of the magnet (20), and the second rotating shaft (from the one end surface of the magnet (20) along the axial direction of the first rotating shaft (11). 12) A second extending portion (22a, 22b, 24a, 24c) extending to the side is provided, and the third soft magnetic member (25, 26) includes the first extending portion (21a, 21b). , 23a, 23b) facing the lower surface and having the same shape as the first extending portion (21a, 21b, 23a, 23b) Opposing the arc portions (25a, 25b, 26a, 26b) and the lower surfaces of the second extension portions (22a, 22b, 24a, 24c), the second extension portions (22a, 22b, 24a, 24c). ) Having the same shape as the second arc portion (25c, 25d, 26c, 26d), the first arc portion (25a, 25b, 26a, 26b) and the second arc portion (25c, 25d, 26c). , 26d), and the fourth soft magnetic member (27) has an inner peripheral surface thereof that is the first extending portion (21a, 21b, 23a, 23b) is formed in a ring shape so as to be opposed to the outer peripheral surface with a predetermined gap, and the inner surface of the fifth soft magnetic member (28) is the second extending portion (22a). 22b, 24a, 24c) with a predetermined gap from the outer peripheral surface. Have the formed ring-shaped to, vehicle detection device according to [1] (1).

[3] The first extending portion (21a, 21b, 23a, 23b) and the first arc portion (25a, 25b, 26a, 26b) facing each other, and the second extending portion (22a, 22b, 24a, 24c) and the second arc portion (25c, 25d, 26c, 26d) are divided in the circumferential direction of the first rotating shaft, according to [1] or [2]. Vehicle detection device (1).

  While the embodiments of the present invention have been described above, the embodiments described above do not limit the invention according to the claims. In addition, it should be noted that not all the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

  The present invention can be appropriately modified and implemented without departing from the spirit of the present invention. For example, in the above-described embodiment, the detection magnet 20 has a four-pole configuration including two pairs of magnetic poles (N pole and S pole), but may be constituted by a ring magnet having two poles or six or more poles. In this case, a yoke corresponding to the first to fourth yokes may be provided for each magnetic pole corresponding to the number of poles of the detection magnet and the boundary between the N pole and the S pole.

  In the above embodiment, the magnetic flux is detected by the magnetic detection element 35 and the angle magnetic detection element 36. However, the number and shape of the magnetic detection element 35 and the angle magnetic detection element 36 are not particularly limited.

  In the above embodiment, the outer peripheral surfaces of the first and third yokes 21 and 23 are formed to face each other with a predetermined gap from the inner peripheral surface of the first guide ring 27. Therefore, the lower surface of the portion extending in the radial direction B from the first and third yokes 21, 23 may be disposed on the first guide ring 27. The upper surface of the upper surface or the portion extending in the radial direction B from the first and third yokes 21 and 23 is the radial direction from the lower surface of the first guide ring 27 or from the first and third yokes 21 and 23. The portions extending to B may be arranged so as to sandwich the upper surface and the lower surface of the first guide ring 27, respectively. Thus, when arrange | positioning on an upper surface and / or a lower surface, the shape of the 1st and 3rd yokes 21 and 23 is not limited to circular arc shape, What is necessary is just a shape in which magnetic coupling does not change.

  In the above embodiment, the outer peripheral surfaces of the second and fourth yokes 22 and 24 are formed so as to face each other with a predetermined gap from the inner peripheral surface of the second guide ring 28. Therefore, the second and fourth yokes 22 and 24 are provided with a portion extending in the radial direction B from the substantially Z shape, and the lower surface of the second and fourth yokes 22 and 24 has a lower surface. The upper surface of the second guide ring 27 or the upper surface of the second and fourth yokes 22 and 24 extending in the radial direction B from the substantially Z shape is the lower surface of the second guide ring 28 or the second The portions extending in the radial direction B from the substantially Z shape of the fourth yokes 22 and 24 may be disposed so as to sandwich the upper surface and the lower surface of the second guide ring 28, respectively. Thus, when arrange | positioning on an upper surface and / or a lower surface, the shape of the 2nd and 4th yokes 22 and 24 is not limited to circular arc shape, What is necessary is just a shape by which magnetic coupling does not change.

  In the embodiment described above, the angle magnetic detection element 36 is disposed on the side of the detection magnet 20 and above the holding members 29 and 30, but the first to sixth components that constitute the torque detection unit 2. Any other place may be used as long as it is hardly affected by the magnetic interference from the yokes 21 to 26 and the first and second guide rings 27 and 28.

  In the above embodiment, the case where the steering angle, that is, the rotation angle is detected has been described. However, by providing a means for detecting the rotation speed of the steering shaft 10, the absolute rotation position of the steering shaft 10 is detected. It may be.

  In the above-described embodiment, the description has been given of the case where each of the first to sixth yokes 21 to 26 facing each other is divided into two in the circumferential direction. There may be. Further, the opposing portions of the first to sixth yokes 21 to 26 are divided along the radial direction B, and a groove (concave portion) along the circumferential direction is provided on one of the opposing yokes, and this groove ( The opposing area of each yoke may be enlarged by providing a convex part that enters the concave part) with a predetermined gap.

DESCRIPTION OF SYMBOLS 1 ... Vehicle detection apparatus 10 ... Steering shaft 11 ... Input shaft 12 ... Output shaft 13 ... Torsion bar (elastic member)
2 ... Torque detection unit 20 ... Detection magnet 21 ... First yoke (first soft magnetic member)
22 ... Second yoke (second soft magnetic member)
23. Third yoke (first soft magnetic member)
24. Fourth yoke (second soft magnetic member)
25. Fifth yoke (third soft magnetic member)
26: Sixth yoke (third soft magnetic member)
27. First guide ring (fourth soft magnetic member)
28: Second guide ring (fifth soft magnetic member)
21a, 21b, 23a, 23b ... 1st extension part (branch part)
22a, 22b, 24a, 24b ... 2nd extension part (branch part)
25a, 25b, 26a, 26b ... 1st circular arc part 25c, 25d, 26c, 26d ... 2nd circular arc part 25e, 26e ... 3rd circular arc part 29, 30, 31 ... Holding member 3 ... Rotation detection part 35 ... Magnetic detection element 36 ... Magnetic detection elements for angles M1, M2, M3 ... Magnetic path

Claims (3)

A shaft-like elastic member that couples the first rotating shaft and the second rotating shaft and is twisted according to the torque transmitted between the first rotating shaft and the second rotating shaft;
An annular magnet provided to rotate with the first rotating shaft;
It rotates with the first rotating shaft and the magnet, and is arranged on the outer peripheral surface of the magnet so as to be magnetically coupled to one magnetic pole of the magnet, and from the one end surface of the magnet to the first rotating shaft A first soft magnetic member provided so as to extend along the axial direction of
It rotates with the first rotating shaft and the magnet, and is disposed on the outer peripheral surface of the magnet so as to be magnetically coupled to the other magnetic pole of the magnet, and from the one end surface of the magnet to the first rotating shaft A second soft magnetic member provided to extend along the axial direction of
A third soft magnetic member provided to rotate together with the second rotating shaft and disposed with a predetermined gap so as to be magnetically coupled to the first and second soft magnetic members;
A fourth soft magnetic member magnetically coupled with a predetermined gap so that the magnetic resistance does not change with respect to the rotating first soft magnetic member;
A fifth soft magnetic member magnetically coupled with a predetermined gap so that the magnetic resistance does not change with respect to the rotating second soft magnetic member;
A magnetic detection element for detecting a magnetic flux density generated between the fourth and fifth soft magnetic members;
A rotation detector that is disposed on a side of the magnet and detects a rotation angle of the first rotation shaft by detecting a magnetic flux density that changes with rotation of the magnet;
A vehicle detection device comprising: The first soft magnetic member has an inner peripheral surface fixed to the outer peripheral surface of the magnet, and extends from one end surface of the magnet to the second rotating shaft side along the axial direction of the first rotating shaft. A first extending portion extending out,
The second soft magnetic member has an inner peripheral surface fixed to the outer peripheral surface of the magnet, and extends from the one end surface of the magnet to the second rotating shaft side along the axial direction of the first rotating shaft. A second extending portion extending,
The third soft magnetic member is opposed to the lower surface of the first extending portion, has a first arc portion having the same shape as the first extending portion, and a lower surface of the second extending portion. A second arc part having the same shape as the second extension part, and a third arc part connecting the first arc part and the second arc part,
The fourth soft magnetic member has a ring shape formed so that an inner peripheral surface thereof is opposed to an outer peripheral surface of the first extension part with a predetermined gap,
The fifth soft magnetic member has a ring shape formed so that an inner peripheral surface thereof is opposed to an outer peripheral surface of the second extending portion with a predetermined gap.
The vehicle detection device according to claim 1. The first extending portion and the first arc portion that face each other, and the second extending portion and the second arc portion are divided in the circumferential direction of the first rotating shaft,
The vehicle detection device according to claim 2 .

Images