JP2016095281A - Detection device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detection device that can be made smaller and accurately detects torque applied to a rotation axis and a rotation position without considering interference of magnetic fluxes between a magnet in a rotation detection unit and a magnet in a torque detection unit.SOLUTION: A detection device for a vehicle 1 detects torque transferred by a torsion bar 13 coupling an input shaft 11 with an output shaft 12, and its rotation position. The device comprises: an annular magnet 20 provided on the input shaft 11; yokes 21, 22 connected with the N and S poles of the magnet 20 respectively, and extending along the axis direction of a rotation axis; yoke 23 provided on the output shaft 12 with a prescribed gap so as to magnetically couple with the yokes 21, 22; a guide ring 24 magnetically coupled with the yoke 21 with a prescribed gap; a guide ring 25 magnetically coupled with the yoke 22 with a prescribed gap; a magnetic detection element 26 for detecting magnetic flux density occurring between the guide rings 24, 25; and a rotation detection unit 29 for detecting magnetic flux density changing as the magnet 20 rotates.SELECTED DRAWING: Figure 1

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. The first magnet is disposed on the inner 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 rotation shaft. A soft magnetic member, the first rotating shaft and the magnet rotate together, and are arranged on the inner peripheral surface of the magnet so as to be magnetically coupled to the other magnetic pole of the magnet, from one end surface 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 magnetically coupled with a predetermined gap so that the magnetic resistance does not change with respect to the rotating first soft magnetic member, and a magnetic force with respect to the rotating second soft magnetic member. A fifth soft magnetic member magnetically coupled with a predetermined gap so that the resistance does not change; a magnetic detecting element for detecting a magnetic flux density generated between the third and fourth soft magnetic members; and the magnet And a rotation detector that detects a rotation angle of the first rotation shaft by detecting a magnetic flux density that changes with rotation of the magnet. .

  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 sectional drawing which shows the structural example of the detection apparatus for vehicles which concerns on embodiment of this invention. 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, and is a perspective view which shows the state by which the torsion bar 13 has not twisted. It is a figure for demonstrating operation | movement of the detection apparatus 1 for vehicles, and is a perspective view which shows the state which the twist generate | occur | produced in the torsion bar 13. FIG. 3B is a diagram showing a positional relationship between the first, second, and third yokes 21, 22, and 23 in FIG. 3A, and is a perspective view seen from the upper right front of FIG. 3A. 3B is a diagram showing a positional relationship between the first, second, and third yokes 21, 22, and 23 in FIG. 3B, and is a perspective view seen from the upper right front in FIG. 3B. It is a figure which shows the modification which added the deformation | transformation to the shape of each opposing surface of the 1st yoke 21, the 2nd yoke 22, and the 3rd yoke 23.

[Embodiment]
FIG. 1 is a cross-sectional view illustrating a configuration example of a vehicle detection device according to an embodiment of the present invention. 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 is fixed to a cylindrical detection magnet 20 fixed to the input shaft 11 so as to surround the input shaft 11 and an inner peripheral surface near the center of each magnetic pole of the detection magnet 20. A first yoke 21 serving as a first soft magnetic member, a second yoke 22 serving as a second soft magnetic member, and an annular fixed to the vehicle body side so as to surround the periphery of the rotating first yoke 21 A first guide ring 24 serving as a fourth soft magnetic member and a second guide ring serving as an annular fifth soft magnetic member fixed to the vehicle body side so as to surround the periphery of the rotating second yoke 22 25, a third yoke 23 serving as a third soft magnetic member in the shape of a semicircular ring and spaced apart with a predetermined gap at the lower end surfaces of the first and second yokes 21 and 22; A magnetic sensor disposed between the first and second guide rings 24, 25. Comprises an element 26, a holding member 27 formed from a mold resin for holding the first and second guide rings 24 and 25, and a holding member 28 formed from a mold resin for holding the third yoke 23.

  The first and second guide rings 24 and 25 and the magnetic detection element 26 are formed on the holding member 27 as inserts. The holding member 27 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 24 and 25 and the magnetic detection element 26 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 to the periphery of the input shaft 11 of the steering shaft 10 via first and second yokes 21 and 22. The detection magnet 20 is disposed so as to rotate integrally with the input shaft 11 of the steering shaft 10. The detection magnet 20 has a pair of magnetic poles (N pole and S pole) formed along the radial direction B. The detection magnet 20 is a permanent magnet having a two-pole configuration in which an S pole is formed on the right side (on the magnetic detection element 26 side) and an N pole is formed on the opposite left side in FIG. For example, a ferrite magnet or a neodymium magnet can be used as the detection magnet 20.

  The first yoke 21 is fixed to the inner peripheral surface near the center of the north pole of the detection magnet 20. The first yoke 21 rotates together with the steering shaft 10. The first yoke 21 extends from the lower end surface of the detection magnet 20 toward the output shaft 12 along the axial direction A of the steering shaft 10 so as to be magnetically coupled to the first guide ring 24. When the first yoke 21 rotates, a predetermined gap is maintained between the first yoke 21 and the first guide ring 24 so that the magnetic resistance does not change due to the rotation. Similarly, the second yoke 22 is fixed to the inner peripheral surface near the center of the south pole of the detection magnet 20 and rotates together with the steering shaft 10. The second yoke 22 extends from the lower end surface of the detection magnet 20 toward the output shaft 12 along the axial direction A of the steering shaft 10 so as to be magnetically coupled to the second guide ring 25. When the second yoke 22 rotates, a predetermined gap is maintained between the second yoke 22 and the second guide ring 25 so that the magnetic resistance does not change due to the rotation. The detection magnet 20 and the first and second yokes 21 and 22 may be insert-molded on a holding member (not shown).

  On the other hand, the third yoke 23 is insert-molded in the holding member 28. The holding member 28 is fixedly attached around the output shaft 12 of the steering shaft 10. Thus, the third yoke 23 is disposed so as to rotate integrally with the output shaft 12 of the steering shaft 10.

  In the present embodiment, the magnetic detection element 26 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 26 has a pair of elements arranged so that the magnetic flux density detection directions 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 is an angle magnetic detection element disposed above the holding member 28 so as to be along the upper end surface of the detection magnet 20 and the side of the south pole of the detection magnet 20. 29. Here, “side” means outward in the radial direction B.

  The angle magnetic detection element 29 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 29 may be insert-molded in the holding member 27. Since the holding member 27 is fixed to the vehicle body via the column housing, even if the steering shaft 10 rotates, the angle magnetic detection element 29 does not rotate with the steering shaft 10 and its position is fixed.

  The angle magnetic detection element 29 sets the detection direction of the change in the magnetic flux density as the biaxial direction of the radial direction B orthogonal to the steering shaft 10 and the direction orthogonal 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 29, 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. 2 is an exploded perspective view showing a configuration example of a magnetic circuit in the vehicle detection device 1. 2, illustration of the steering shaft 10 and the holding members 27 and 28 in FIG. 1 is omitted.

  In the present embodiment, the detection magnet 20 is composed of a two-pole magnet having a semi-cylindrical N pole and S pole along the radial direction B of the steering shaft 10 as described above.

  The first and second yokes 21 and 22 are provided so as to rotate together with the input shaft 11 and the detection magnet 20. The first yoke 21 is the inner peripheral surface of the detection magnet 20 and is near the center of one of the magnetic poles (N pole in the figure) (the boundaries 20a and 20b between the N pole and S pole of the detection magnet 20). It is fixed at almost the middle position). As a cross-sectional shape in the direction perpendicular to the axial direction A of the first yoke 21, the inner periphery of the detection magnet 20 is the outer periphery, the outer periphery of the input shaft 11 is the inner periphery, and the steering shaft 10 extends from the lower end surface of the detection magnet 20. The outer circumference of the input shaft 11 is defined as the outer circumference of the first fan-shaped portion 211 extending toward the output shaft 12 along the axial direction A and the circumference formed by a predetermined gap from the inner circumference of the first guide ring 24. And a second sector 212 having an inner circumference. The outer peripheral surface of the second sector 212 of the first yoke 21 is formed so as to face the inner peripheral surface of the first guide ring 24 with a predetermined gap.

  The second yoke 22 is an inner peripheral surface of the detection magnet 20 and is near the center of the other magnetic pole (S pole in the figure) (on the boundaries 20a and 20b between the N pole and S pole of the detection magnet 20). It is fixed at almost the middle position). As the cross-sectional shape of the second yoke 22 in the direction perpendicular to the axial direction A, the inner periphery of the detection magnet 20 is the outer periphery, the outer periphery of the input shaft 11 is the inner periphery, and the steering shaft 10 extends from the lower end surface of the detection magnet 20. The outer periphery of the input shaft 11 is defined as a third fan-shaped portion 221 extending toward the output shaft 12 along the axial direction A and a periphery formed by a predetermined gap from the inner periphery of the second guide ring 25. And a fourth sector 222 having an inner circumference. The outer peripheral surface of the fourth sector 222 of the second yoke 22 is formed to face the inner peripheral surface of the second guide ring 25 with a predetermined gap.

  The first guide ring 24 is disposed such that the inner peripheral surface thereof faces the outer peripheral surface of the second sector 212 of the first yoke 21 in the axial direction A of the steering shaft 10. The first guide ring 24 is formed concentrically around the torsion bar 13 as a central axis, and is arranged with a predetermined gap from the outer periphery of the second sector 212 of the first yoke 21; A projecting portion 241 projecting radially outward from the annular portion 240, an extending portion 242 extending from the one end of the projecting portion 241 opposite to the annular portion 240 toward the second guide ring 25, and an extending portion 242 Projecting from the end opposite to the projecting portion 241 to the radially outer side of the annular portion 240 (in the present embodiment, the direction parallel to the projecting portion 241), and opposed to the facing portion 253 of the second guide ring 25 described later. And an opposing portion 243 that is integrated.

  The second guide ring 25 is disposed such that its inner peripheral surface faces the outer peripheral surface of the fourth sector 222 of the second yoke 22. The second guide ring 25 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 fourth sector 222 of the second yoke 22; A projecting portion 251 projecting radially outward from the annular portion 250, an extending portion 252 extending from one end of the projecting portion 251 opposite to the annular portion 250 toward the first guide ring 24, and an extending portion 252 Projecting from the one end opposite to the projecting portion 251 to the radially outer side of the annular portion 250 (in the present embodiment, the direction parallel to the projecting portion 251) and facing the facing portion 243 of the first guide ring 24 It has the part 253 integrally.

  The protrusions 241 and 251, the extension parts 242 and 252, and the opposing parts 243 and 253 of the first and second guide rings 24 and 25 are formed so as to extend outward from the annular parts 240 and 250 by punching. The rectangular portion thus formed can be easily manufactured by bending.

  The third yoke 23 faces the lower surface of the second sector 212 of the first yoke 21 and has a fifth sector 231 having the same shape as the second sector 212 of the first yoke 21; A sixth sector 232 facing the lower surface of the fourth sector 222 of the second yoke 22 and having the same shape as the fourth sector 222, a fifth sector 231 and a sixth sector 232 And a seventh fan-shaped portion 233 connecting the two.

  The lower surfaces of the fifth sector 231, the sixth sector 232, and the seventh sector 233 of the third yoke 23 are common to each other. The height of the third yoke 23 from the lower surface of the fifth sector 231 and the sixth sector 232 is the second height of the first yoke 21 from the upper surface of the fifth sector 231 of the third yoke 23. The distance to the lower surface of the fan-shaped portion 212 and the distance from the upper surface of the sixth fan-shaped portion 232 of the third yoke 23 to the lower surface of the fourth fan-shaped portion 222 of the second yoke 22 are set to be equal. Has been. The height from the lower surface of the seventh sector 233 is the smallest, and the height from the lower surface of the second sector 212 of the first yoke 21 and the fourth sector 222 of the second yoke 22 is reduced. It is formed to be equal to the height.

  Between the facing portion 243 of the first guide ring 24 and the facing portion 253 of the second guide ring 25, the magnetic detection element 26 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. The first magnetic path M1 is, as indicated by the alternate long and short dash line in FIG. 2, the N pole of the detection magnet 20 → the first yoke 21 → the first guide ring 24 → the second guide ring 25 → the second yoke. 22 → S pole of the detection magnet 20 and the second magnetic path M2 is the N pole of the detection magnet 20 → the first yoke 21 → the third yoke 23 → the second yoke 22 → the detection magnet 20 S pole. The third magnetic path M3 includes the N pole of the detection magnet 20 → the first yoke 21 → the third yoke 23 → the first guide ring 24 → the second guide ring 25 → the second yoke 22 → for detection. It becomes the south pole of the magnet 20. The third magnetic path M3 is common to the second magnetic path M2 before branching from the third yoke 23 to the first guide ring 24, and is common to the first magnetic path M1 after branching. It has become. In the present 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, M3 can be ignored. Small enough.

(Operation of vehicle detection device)
3A and 3B are diagrams for explaining the operation of the vehicle detection device 1. FIG. 3A is a perspective view showing a state in which the torsion bar 13 is not twisted, and FIG. 3B is a diagram in which the torsion bar 13 is twisted. It is a perspective view which shows a state. 3, illustration of the steering shaft 10 and the holding members 27 and 28 in FIG. 1 is 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, the first yoke 21, and the second yoke 22 rotate in accordance with the rotational direction in which the rotation is steered. On the other hand, the third yoke 23 rotates with a delay due to the twist generated in the torsion bar 13, so that the rotational position is relative to the first yoke 21 and the second yoke 22 as shown in FIG. 3B. It becomes relatively displaced.

  4A and 4B are diagrams showing the positional relationship between the first, second, and third yokes 21, 22, and 23 of FIGS. 3A and 3B, as viewed from the upper right front of FIGS. 3A and 3B. It is a perspective view. As shown in FIG. 4A, in a state where the torsion bar 13 is not twisted, the lower surface of the second sector 212 of the first yoke 21 and the upper surface of the fifth sector 231 of the third yoke 23 , And the area where the lower surface of the fourth sector 222 of the second yoke 22 and the upper surface of the sixth sector 232 of the third yoke 23 are opposite to each other. As a result, when the torsion bar 13 is twisted and the third yoke 23 is displaced relative to the first yoke 21 and the second yoke 22, as shown in FIG. The area where the lower surface of the second sector 212 and the upper surface of the fifth sector 231 of the third yoke 23 face each other, and the lower surface of the fourth sector 222 of the second yoke 22 and the third yoke 23. The area where the upper surface of the sixth sector portion 232 faces each other decreases.

  Thereby, in the magnetic path M2, the magnetic flux density of the magnetic flux supplied from the N pole of the detection magnet 20 via the first yoke 21 to the third yoke 23 is rapidly lowered. On the other hand, the magnetic flux density of the magnetic flux supplied from the N pole of the detection magnet 20 to the first guide ring 24 via the first yoke 21 in the magnetic path M1 increases rapidly. Therefore, the magnetic detection element 26 detects the amount of twist 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 magnetic flux density passing through the magnetic path M1. Is possible.

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

(1) Since the magnetic detection element 26 is arranged in series with respect to the magnetic paths M1 and M3 and is arranged in parallel with respect to the magnetic path M2, the magnitude of the magnetic flux detected by the magnetic detection element 26 is large. The area where the lower surface of the second sector 212 of the first yoke 21 and the upper surface of the fifth sector 231 of the third yoke 23 are opposed to each other, and the fourth sector of the second yoke 22. It depends on the size of the area where the lower surface of 222 and the upper surface of the sixth sector 232 of the third yoke 23 face each other. Thereby, the magnetic detection element 26 can detect the amount of change of the magnetic flux with high accuracy according to the amount of torque acting on the input shaft 11.

(2) Since the magnetic detection elements 26 are arranged in series in the magnetic paths M1 and M3 and are arranged in parallel to the magnetic path M2, the third yoke 23 and the first yoke 21 Since the magnetic flux density flowing through the entire magnetic paths M1, M2, and M3 is less likely to change even when the magnetic resistance between the magnetic yoke M23 and the magnetic resistance between the third yoke 23 and the second yoke 22 changes. The influence on the angle magnetic detection element 29 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.

[Modification]
Next, a modification of the present invention will be described with reference to FIG. FIG. 5 is a view showing a modification in which the shapes of the facing surfaces of the first yoke 21, the second yoke 22 and the third yoke 23 are modified, and corresponds to FIG. In this modified example, the first yoke 21A divides the second sector 212 of the first yoke 21 into three equal parts in the circumferential direction, and two of them are arranged at both ends as sector portions 212A and 212B. It is a thing. The second yoke 22A is obtained by dividing the fourth sector 222 of the second yoke 22 into three equal parts in the circumferential direction, and arranging two of them as sector portions 222A and 222B at both ends thereof. The third yoke 23A divides the fifth sector 231 and the sixth sector 232 of the third yoke 23 into three equal parts in the circumferential direction, and two of them are sector parts 231A, 231B, 232A, 232B. As shown in FIG.

  For example, when the central angle of the sector part before being divided into three equal parts is 45 degrees, the central angle of the sector part after the division is 15 degrees. The angle of the fan-shaped portion is determined according to the maximum twist angle of the torsion bar 13. When the maximum twist angle of the torsion bar 13 is about 30 degrees, the central angle is preferably about 45 degrees as in the fan-shaped portion shown in the above embodiment, and when the maximum twist angle is about 10 degrees. As in this modification, the central angle of the sector is preferably about 15 degrees.

(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 inner peripheral surface of the magnet (20) so as to be magnetically coupled to one magnetic pole (N pole) of the magnet (20). 20), a first soft magnetic member (21) provided so as to extend along the axial direction of the first rotating shaft (11), the first rotating shaft (11), and The magnet (20) rotates with the magnet (20) and is magnetically coupled to the other magnetic pole (S pole) of the magnet (20). 0) and a second soft magnetic member (22) provided so as to extend from one end surface of the magnet (20) along the axial direction of the first rotating shaft (11). ) And the second rotating shaft (12) so as to rotate with a predetermined gap so as to be magnetically coupled to the first and second soft magnetic members (21, 22). A fourth soft magnetic member (23) disposed and a fourth soft magnetic member magnetically coupled to the rotating first soft magnetic member (21) with a predetermined gap so that the magnetic resistance does not change. A magnetic member (24) and a fifth soft magnetic member (25) magnetically coupled with a predetermined gap so that the magnetic resistance does not change with respect to the rotating second soft magnetic member (22); Detects the magnetic flux density generated between the third and fourth soft magnetic members (24, 25). Of the first rotating shaft (11) by detecting a magnetic flux density which is arranged on the side of the magnetism detecting element (26) and the magnet (20) and which changes as the magnet (20) rotates. A vehicle detection device (1) comprising: a rotation detection unit (29) for detecting a rotation angle.

[2] An outer peripheral surface of the first soft magnetic member (21) is fixed to an inner peripheral surface of the magnet (20), an inner periphery of the magnet (20) is an outer periphery, and the first rotating shaft is provided. A first sector portion having an outer periphery of (11) as an inner periphery and extending from one end surface of the magnet (20) toward the second rotation shaft (12) along the axial direction of the first rotation shaft. (211) and an outer periphery of the first rotating shaft (11) as an inner periphery, and an outer periphery of the outer periphery is defined by a predetermined gap from the inner peripheral surface of the third soft magnetic member (24). The second soft magnetic member (22) is fixed to the inner peripheral surface of the magnet (20), and the second soft magnetic member (22) is fixed to the inner peripheral surface of the magnet. An outer periphery, and an outer periphery of the first rotating shaft (11) is an inner periphery, from the one end surface of the magnet (20) to the axial direction of the first rotating shaft (11). Thus, the outer periphery of the third fan-shaped portion (221) extending toward the second rotating shaft (12) and the outer periphery of the first rotating shaft (11) is the fourth outer periphery. A fourth sector part (222) having an outer periphery defined by a predetermined gap from the inner peripheral surface of the soft magnetic member (25), and the third soft magnetic member (23) The second fan-shaped part (212) is opposed to the lower surface of the second fan-shaped part (212), and the fifth fan-shaped part (231) having the same shape as the second fan-shaped part (212) is opposed to the lower surface of the fourth fan-shaped part (222). And a sixth sector (232) having the same shape as the fourth sector (222), a fifth sector (231), and a sixth sector (232) connecting the sixth sector (232). The fourth soft magnetic member (24) has an inner peripheral surface that is the outer periphery of the second sector (212). The fifth soft magnetic member (25) has a ring shape formed so as to be opposed to each other with a predetermined gap from the outer peripheral surface of the fourth sector (222). The vehicle detection device (1) according to the above [1], which has a ring shape formed so as to face each other with a gap.

[3] The second sector part (212) and the fifth sector part (231), the fourth sector part (222) and the sixth sector part (232), which are opposed to each other, The vehicle detection device according to [1] or [2], including a plurality of fan-shaped portions (212A, 212B, 222A, 222B, 231A, 231B, 232A, 232B) divided in the circumferential direction of one rotation shaft. (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 present embodiment are essential for 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 two-pole configuration including a pair of magnetic poles (N pole and S pole) along the radial direction B. Good. In this case, the first, second, and third 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 26 and the angle magnetic detection element 29. However, the number and shape of the magnetic detection element 26 and the angle magnetic detection element 29 are not particularly limited.

  In the above embodiment, the outer peripheral surface of the second sector 212 of the first yoke 21 is formed to face the inner peripheral surface of the first guide ring 24 with a predetermined gap. The lower surface of the first yoke 21 may be disposed on the upper surface of the first guide ring 24 and the upper surface of the first yoke 21 may be disposed on the first surface so that the magnetic coupling is not changed by rotation. The lower surface of one guide ring 24 or the first yoke 21 may be arranged so as to sandwich the upper surface and the lower surface of the first guide ring 24, respectively. Thus, when arrange | positioning on an upper surface and / or a lower surface, the shape of the 1st yoke 21 is not limited to a fan shape, What is necessary is just a shape which magnetic coupling does not change.

  In the above embodiment, the outer peripheral surface of the fourth sector 222 of the second yoke 22 is formed to face the inner peripheral surface of the second guide ring 25 with a predetermined gap. Since it is only necessary that the magnetic coupling is arranged with a predetermined gap so that the magnetic coupling is not changed by the rotation, the lower surface of the second yoke 22 is on the upper surface of the second guide ring 25 and the upper surface of the second yoke 22 is on the first surface. The second yoke 22 may be disposed on the lower surface of the second guide ring 25 so as to sandwich the upper surface and the lower surface of the second guide ring 25. Thus, when arrange | positioning on an upper surface and / or a lower surface, the shape of the 1st yoke 21 is not limited to a fan shape, What is necessary is just a shape which magnetic coupling does not change.

  In the above-described embodiment, the angle magnetic detection element 29 is disposed on the side of the detection magnet 20 and above the holding member 27. However, the first, second, and third components constituting the torque detection unit 2 are used. Other locations may be used as long as they are difficult to be affected by the magnetic interference from the yokes 21, 22, and 23 and the first and second guide rings 24 and 25.

  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 modification, the description has been given of the case where the opposing portions of the first to third yokes 21A, 22A, and 23A are divided into two in the circumferential direction, but they may be further divided into multiple parts. Further, the opposing portions of the first to third yokes 21, 22, 23, 21A, 22A, and 23A are divided along the radial direction B, and grooves (concave portions) along the circumferential direction are formed on one of the opposing yokes. May be provided, and on the other side, a convex portion that enters the groove (concave portion) with a predetermined gap may be provided, so that the opposing area of each yoke may be increased.

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 magnets 20a, 20b ... Boundaries 21, 21A ... First yoke (first soft magnetic member)
22, 22A ... second yoke (second soft magnetic member)
23, 23A ... third yoke (third soft magnetic member)
211 ... first sector 212 ... second sector 221 ... third sector 222 ... fourth sector 231 ... fifth sector 232 ... sixth sector 233 ... seventh sector 24 ... First guide ring (fifth soft magnetic member)
25. Second guide ring (sixth soft magnetic member)
26 ... Magnetic detection elements 27, 28 ... Holding member 29 ... Angle magnetic detection element 3 ... Rotation detector 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 inner peripheral surface of the magnet so as to be magnetically coupled to one magnetic pole of the magnet, and the first rotation from the one end surface of the magnet A first soft magnetic member provided to extend along the axial direction of the shaft;
It rotates with the first rotating shaft and the magnet, and is disposed on the inner peripheral surface of the magnet so as to be magnetically coupled to the other magnetic pole of the magnet, and the first rotation from the one end surface of the magnet A second soft magnetic member provided to extend along the axial direction of the 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 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 third and fourth 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 outer surface of the first soft magnetic member is fixed to the inner peripheral surface of the magnet, the inner periphery of the magnet is the outer periphery, the outer periphery of the first rotating shaft is the inner periphery, and one end surface of the magnet The first fan-shaped portion extending to the second rotating shaft side along the axial direction of the first rotating shaft from the outer periphery of the first rotating shaft is defined as the inner periphery, and the outer peripheral surface is the first rotating shaft. A second fan-shaped portion having an outer periphery defined by a predetermined gap from the inner peripheral surface of the soft magnetic member,
The second soft magnetic member has an outer peripheral surface fixed to an inner peripheral surface of the magnet, an inner periphery of the magnet as an outer periphery, an outer periphery of the first rotating shaft as an inner periphery, and the one of the magnets. A third sector extending from the end surface along the axial direction of the first rotating shaft toward the second rotating shaft, and an outer periphery of the first rotating shaft as an inner periphery, the outer peripheral surface of which is A fourth sector having a circumference formed by a predetermined gap from the inner circumferential surface of the fourth soft magnetic member,
The third soft magnetic member is opposed to the lower surface of the second sector part, and is opposed to the fifth sector part having the same shape as the second sector part, and the lower surface of the fourth sector part. The sixth sector having the same shape as the fourth sector, and the seventh sector connecting the fifth sector and the sixth sector,
The fourth soft magnetic member has a ring shape formed such that an inner peripheral surface thereof is opposed to an outer peripheral surface of the second sector portion with a predetermined gap,
The fifth soft magnetic member has a ring shape formed such that an inner peripheral surface thereof is opposed to an outer peripheral surface of the fourth sector portion with a predetermined gap.
The vehicle detection device according to claim 1. A plurality of sector portions obtained by dividing the second sector portion and the fifth sector portion, and the fourth sector portion and the sixth sector portion, which face each other, in the circumferential direction of the first rotation axis. The vehicle detection device according to claim 1 or 2.

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