JP2002116095A - Rotation angle detecting device, torque detecting device, and steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotation angle detecting device of a simple structure which does not require skill of workmen for adjusting operations. SOLUTION: The rotation angle detecting device is provided with a rotor 2, a target 20 provided for the rotor 2 so that sections to be detected are continuously changed according to the rotation of the rotor 2, and one or a plurality of detecting means 1A, 1B, (2A, and 2B) for detecting the adjacent sections of the target 20 and detects the angle displacement in the direction of rotation of the rotor 2 on the basis of the sections detected by the detecting means 1A, 2B, (2A, and 2B). The target 20 comprises one or a plurality of surfaces 20a which include the sections and which are protruded parts protruded from the circumferential surface of the rotor 2, and the detecting means 1A, 1B, (2A, and 2B) output detection signals according to the distances to the surfaces 20a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation angle detection device for detecting a rotation angle, a torque detection device for detecting a torque applied to an input shaft by a torsion angle generated in a connecting shaft connecting an input shaft and an output shaft, and The present invention relates to a steering device for an automobile provided with the torque detecting device.

[0002]

2. Description of the Related Art A steering assist motor is driven based on a detection result of a steering torque applied to a steering wheel (steering wheel) for steering, and a torque of the motor is transmitted to a steering device to assist the steering. The electric power steering device, which has been described, is compared with a hydraulic power steering device using a hydraulic actuator as a source of steering assist force.
Since it has the advantage that it is easy to control the assist force characteristics according to the driving conditions such as the speed of the vehicle and the frequency of steering,
In recent years, its application range has tended to expand.

In the electric power steering apparatus described above, a torque detecting device for detecting a steering torque is required, and a steering shaft for connecting a steering wheel and a steering mechanism is connected to an input shaft on the steering wheel side and a steering wheel. The output shaft on the mechanism side is connected via a small-diameter torsion bar, and the relative displacement generated at the connection between the two shafts is detected based on the detection result, with the torsion of the torsion bar due to the action of the steering torque. Thus, a torque detecting device configured to calculate the steering torque (rotation torque) is used.

[0004] This torque detecting device is disclosed in
A non-contact type torque detecting device is known as described in Japanese Patent No. 65750. This conventional torque detecting device includes a pair of magnetic rings, which are disposed around one of an input shaft and an output shaft, and have rectangular teeth formed on an end face in a circumferential direction. An annular torque detection coil disposed around the torsion bar, and when the magnetic ring is relatively rotated with the torsion of the torsion bar, the facing area of the teeth changes, and the torque is accordingly adjusted. The impedance of the detection coil changes. The torque detection device is configured to detect the change in the impedance as a relative displacement generated at a connection portion between the two shafts, and calculate the steering torque (rotation torque) based on the detection result.

[0005]

In the conventional non-contact type torque detecting device as described above, an annular torque detecting coil is disposed around a magnetic ring, and furthermore, the torque detecting coil and the end face are rectangular. There is a problem that the structure is complicated because it has a pair of magnetic rings each provided with a toothed portion in the circumferential direction. In addition, when the steering wheel is in a neutral state where no torque is applied, in the adjustment operation for setting the zero point of the torque sensor, the gap between the opposing areas of the teeth of the two magnetic rings and the gap between the teeth are adjusted. Therefore, there is a problem that it is necessary to find out the three-dimensional position of the above, and the skill of the operator is required. In addition, since the steering angle, which is one of the state quantities used for the drive control of the motor, cannot be detected, a dedicated device for detecting the steering angle is required separately.

The present invention has been made in view of the circumstances described above, and in the first to fifth inventions, there is provided a rotation angle detecting device which has a simple structure and does not require the skill of an operator for an adjusting operation. The purpose is to provide. In the sixth invention, the first to first aspects
A fifth object of the present invention is to provide a torque detecting device that can also detect a steering angle by using the rotation angle detecting device according to the invention. In a seventh invention, it is an object to provide a steering device using the torque detection device according to the sixth invention.

[0007]

According to a first aspect of the present invention, there is provided a rotation angle detecting device, comprising: a rotating body;
A target provided on the rotating body and one or more detecting means for detecting a part close to the target so that the detected part changes continuously, based on the part detected by the detecting means. A rotation angle detecting device that detects a displacement angle of the rotating body in a rotating direction, wherein the target has one or more surfaces that should include the part, and a protruding portion that projects from a peripheral surface of the rotating body. Wherein the detection means is adapted to output a detection signal corresponding to a distance from the surface.

[0008] In this rotation angle detecting device, the target is provided on the rotating body so that the portion to be detected changes continuously as the rotating body rotates, and one or a plurality of detecting means is provided near the target. And detecting a displacement angle of the rotating body in the rotation direction based on the detected portion. The target has one or more surfaces including a part to be detected by the detection means, and is a protruding portion protruding from the peripheral surface of the rotating body, and the detection means outputs a detection signal corresponding to a distance from the surface of the target. Output. Accordingly, it is possible to realize a rotation angle detecting device that has a simple structure and does not require the skill of an operator for the adjustment operation.

According to a second aspect of the present invention, there is provided a rotation angle detecting device, wherein the surface is provided on a first inclined surface inclined in one direction from the circumferential direction of the rotating body, and in the other direction from the circumferential direction of the rotating body. It is a second inclined surface provided to be inclined.

In this rotation angle detecting device, the surface of the target has a first inclined surface provided in one direction from the circumferential direction of the rotating body, and a surface inclined in the other direction from the circumferential direction of the rotating body. Since the second inclined surface is provided, the detection signal output from the detection means is stable, the structure is simple, and a rotation angle detection device that does not require the skill of an operator for the adjustment operation can be realized.

According to a third aspect of the present invention, in the rotation angle detecting device, the first inclined surface and the second inclined surface have a substantially plane-symmetric relationship with respect to a plane including an intersection of the two inclined surfaces and a rotation axis of the rotating body. It is characterized by having.

In this rotation angle detecting device, the first inclined surface and the second inclined surface have a substantially plane-symmetric relationship with respect to a plane including the intersection line of the two inclined surfaces and the rotation axis of the rotating body. Thus, it is possible to realize a rotation angle detecting device which has a stable detection signal, a simple structure, and does not require the skill of an operator for the adjusting operation.

[0013] A rotation angle detecting device according to a fourth invention is characterized in that a plurality of the targets are provided continuously along the peripheral surface of the rotating body.

In this rotation angle detecting device, a plurality of targets are provided continuously along the peripheral surface of the rotating body, so that the detection sensitivity is good, the structure is simple, and the adjustment operation requires skill of an operator. It is possible to realize a rotation angle detection device that does not require the rotation.

[0015] A rotation angle detecting device according to a fifth aspect of the present invention is characterized in that the target is a magnetic material and the detecting means is a magnetic sensor.

In this rotation angle detection device, since the target is a magnetic material and the detection means is a magnetic sensor, the cost of parts is low, the structure is simple, and the rotation angle does not require the skill of an operator for the adjustment operation. A detection device can be realized.

According to a sixth aspect of the present invention, there is provided a torque detecting device for detecting a torque applied to an input shaft by a torsion angle generated in a torsion bar coaxially connecting the input shaft and the output shaft. The rotation angle detection device according to any one of claims 1 to 5, which detects a displacement angle of each of the output shafts, and a unit configured to detect a difference between the displacement angles detected by the rotation angle detection device. The difference between the displacement angles detected by the means is set as the torsion angle.

In this torque detecting device, the torque applied to the input shaft is detected based on the torsion angle generated in a torsion bar coaxially connecting the input shaft and the output shaft. Claim 1
The rotation angle detecting device according to any one of ~ 5 detects a displacement angle of each of the input shaft and the output shaft, and the detecting means detects a difference between the displacement angles respectively detected by the rotation angle detecting device, The difference between the displacement angles detected by the detecting means is defined as a torsion angle. As a result, it is possible to realize a torque detection device that has a simple structure and can detect the steering angle by using a rotation angle detection device that does not require skill of an operator for the adjustment operation.

According to a seventh aspect of the present invention, there is provided a steering apparatus comprising: an input shaft connected to a steered wheel; an output shaft connected to a steering mechanism; a torsion bar connecting the input shaft and the output shaft; A torque detecting device according to claim 6, wherein the steering torque applied to the shaft is detected by a torsion angle generated in the torsion bar.

In this steering device, the input shaft is connected to the steered wheels, the output shaft is connected to the steering mechanism, and the torsion bar connects the input shaft and the output shaft. According to a sixth aspect of the present invention, there is provided a torque detecting device that detects a steering torque applied to an input shaft by a torsion angle generated in a torsion bar. As a result, it is possible to realize a steering device having a simple structure, a torque detection device capable of detecting the steering angle without requiring the skill of an operator for the adjusting operation, and the like.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment. Embodiment 1 FIG. FIG. 1 is a schematic diagram schematically showing a configuration of a first embodiment in which a rotation angle detection device and a torque detection device according to the present invention are applied to a steering device of an automobile. The rotation angle detection device and the torque detection device include an input shaft 31 having an upper end connected to a steering wheel (steering wheel) 30;
Output shaft 32 having a lower end connected to a pinion 33 of a steering mechanism
Are connected coaxially via a small-diameter torsion bar 34 to form a steering shaft 3 that connects the steered wheels 30 and a steering mechanism. The torque detecting device includes the input shaft 31 and an output shaft. The vicinity of the connection portion of the shaft 32 is configured as follows.

A disk-shaped target plate 2 (rotary body) is coaxially externally fixed to the input shaft 31 near an end on the side of connection with the output shaft 32. , A plurality (ten in the figure) of targets 20 are juxtaposed. FIG. 2 is a plan view showing the configuration of the target plate 2 and the target 20. The target 20 has substantially the same thickness as the target plate 2, is a protruding portion protruding from the outer peripheral surface of the target plate 2, is inclined in a predetermined direction from the circumferential direction of the target plate 2, and rotates along a rotation axis of the target plate 2. And a plane 20b which should constitute a part of a plane including the rotation axis of the target plate 2 (that is, perpendicular to the peripheral surface of the target plate 2).
Are arranged in a row in the circumferential direction of the outer peripheral surface of the. As shown in FIG. 3, the waveform of a detection signal (sensor output) output from each of the inclined surfaces 20a by detecting the distance between the magnetic sensors 1A and 1B and the inclined surface 20a changes as a substantially straight line as shown in FIG. Thus, it has a curved surface protruding outside.

The target plate 2 provided with the same target 20 as described above is externally fitted and fixed also near the end of the output shaft 32 connected to the input shaft 31, and the target plate 2 on the output shaft 32 side is fixed. And the respective targets 20 of the target plate 2 on the input shaft 31 side are aligned side by side in the circumferential direction.

The sensor boxes 1 are arranged outside the target plates 2 so as to face the inclined surfaces 20a of the respective targets 20. The sensor box 1 is fixedly supported by a stationary part such as a housing that supports the input shaft 31 and the output shaft 32. Inside the sensor box 1, magnetic sensors 1A and 1B facing different portions in the circumferential direction of the target 20 on the input shaft 31 side, and a magnetic sensor 2A facing different portions in the circumferential direction of the target 20 on the output shaft 32 side. , 2B are stored with their circumferential positions correctly aligned.

Each of the magnetic sensors 1A, 2A, 1B, 2B uses an element such as a magnetoresistive effect element (MR element) having a characteristic whose electric characteristic (resistance) changes by the action of a magnetic field. This is a sensor configured to change the detection signal according to the distance from the surface 20a, and these detection signals V1A, V2A, V1B, V2B are processed by an arithmetic processing unit using a microprocessor outside or inside the sensor box 1. 4 given.

Hereinafter, the operation of the rotation angle detecting device and the torque detecting device having such a configuration will be described. Magnetic sensor 1
As described above, the target 20 to which A, 2A, 1B and 2B face each other has substantially the same thickness as each of the target plates 2 coaxially and externally fixed to the input shaft 31 and the output shaft 32. 2 is a projection protruding from the outer peripheral surface of the target plate 2, is inclined in a predetermined direction from the circumferential direction of the target plate 2, and has a slope 20 a parallel to the rotation axis of the target plate 2 and a flat surface including the rotation axis of the target plate 2. It is a magnetic body provided with a flat surface 20b which is to constitute a part thereof and arranged side by side in the circumferential direction at equal intervals.

Therefore, when the input shaft 31 and the output shaft 32 rotate around the axis, each of the magnetic sensors 1A, 1B, 2A, 2
B indicates the respective inclined surfaces 20 of the corresponding targets 20.
a, and their detection signals V1A, V1
B, V2A and V2B are, as shown in FIG.
And a detection signal having a sawtooth waveform that rises (or falls) proportionally according to a change in the rotation angle of the output shaft 32.

The detection signals of the magnetic sensors 1A and 1B correspond to the rotation angles of the input shaft 31 provided with the corresponding targets 20, and are detected by the magnetic sensors 2A and 2B.
These detection signals correspond to the rotation angle of the output shaft 32 provided with the targets 20 facing each other. Therefore, the arithmetic processing unit 4 can calculate the rotation angle of the input shaft 31 from the detection signals of the magnetic sensors 1A and 1B, and the arithmetic processing unit 4 and the magnetic sensors 1A and 1B function as a rotation angle detection device of the input shaft 31. Operate. The arithmetic processing unit 4
Can calculate the rotation angle of the output shaft 32 from the detection signals of the magnetic sensors 2A and 2B, and the arithmetic processing unit 4 and the magnetic sensors 2A and 2B operate as a rotation angle detection device of the output shaft 32.

When a rotational torque is applied to the input shaft 31,
A deviation occurs between the detection signals V1A and V2A of the magnetic sensors 1A, 1B, 2A and 2B and between the detection signals V1B and V2B. However, the magnetic sensors 1A and 2A and the magnetic sensors 1B and 2B have a phase difference of, for example, an electrical angle of 180 ° in the circumferential direction of the target plate 2, and the detection signals V1A and V1B are opposed to the magnetic sensors 1A and 1B. The regions where the target 20a changes alternately can be complemented with each other, and the same applies to the detection signals V2A and V2B.

Here, the detection signal V1A and the detection signal V2A
Or the difference between the detection signal V1B and the detection signal V2B corresponds to the difference in the rotation angle (relative angular displacement) between the input shaft 31 and the output shaft 32. This relative angular displacement is caused by the input shaft 3 under the action of the rotational torque applied to the input shaft 31.
This corresponds to the torsion angle generated in the torsion bar 34 connecting the output shaft 1 and the output shaft 32. Therefore, the rotation torque applied to the input shaft 31 can be calculated based on the difference between the detection signals described above.

Embodiment 2 FIG. 4 is a schematic diagram schematically showing a configuration of a second embodiment in which the rotation angle detection device and the torque detection device according to the present invention are applied to a steering device of an automobile. The rotation angle detecting device and the torque detecting device are configured such that an input shaft 31 whose upper end is connected to a steering wheel (steering wheel) 30 and an output shaft 32 whose lower end is connected to a pinion 33 of a steering mechanism have a small diameter. A steering shaft 3 is connected coaxially through a torsion bar 34 and connects the steering wheel 30 and a steering mechanism. The torque detection device is provided near a connection between the input shaft 31 and the output shaft 32. It is configured as follows.

A disk-shaped target plate 2a (rotating body) is coaxially fixed to the input shaft 31 near the end on the side of connection with the output shaft 32. The outer peripheral surface of the target plate 2a is fixed. Includes a plurality of (five in the figure) targets 20c
Are juxtaposed. FIG. 5 is a plan view showing the configuration of the target plate 2a and the target 20c. Target 2
Reference numeral 0c denotes a projection having substantially the same thickness as the target plate 2a and protruding from the outer peripheral surface of the target plate 2a, which is inclined in one direction from the circumferential direction of the target plate 2a, and It has a parallel inclined surface 20d and an inclined surface 20e inclined in the other direction from the circumferential direction of the target plate 2a and parallel to the rotation axis of the target plate 2a. They are arranged side by side evenly.

As shown in FIG. 6, the waveforms of the detection signals (sensor outputs) output from the magnetic sensors 1A and 1B, which are detected by the magnetic sensors 1A and 1B, detect the distances from the respective inclined surfaces 20d and 20e. , Each of which has a curved surface protruding outward so as to change as a substantially straight line.
It has a substantially plane-symmetric relationship with respect to a plane including the line of intersection of d and 20e and the rotation axis of the target plate 2a.

A target plate 2a provided with the same target 20c as described above is also externally fixed near the end of the output shaft 32 connected to the input shaft 31, and the target plate 2a on the output shaft 32 side is fixed. Target 20c and input shaft 3
Each target 20c of the target plate 2a on one side is aligned side by side in the circumferential direction.

The sensor box 1 is arranged outside the target plates 2a so as to face the inclined surfaces 20d and 20e of the respective targets 20c. The sensor box 1 is fixedly supported by a stationary part such as a housing that supports the input shaft 31 and the output shaft 32. Inside the sensor box 1, magnetic sensors 1A and 1B facing different portions in the circumferential direction of the target 20c on the input shaft 31 side.
The magnetic sensors 2A and 2B facing different portions of the target 20c on the output shaft 32 side in the circumferential direction are housed with their circumferential positions correctly aligned.

Each of the magnetic sensors 1A, 2A, 1B, 2B uses an element such as a magnetoresistive element (MR element) whose electric characteristics (resistance) change by the action of a magnetic field. The sensor is configured so that the detection signal changes according to the distance from the surfaces 20d and 20e, and the detection signals V1A, V2A, V1B, and V2
B is given to an arithmetic processing unit 4 using a microprocessor external or internal to the sensor box 1.

Hereinafter, the operation of the rotation angle detecting device and the torque detecting device having such a configuration will be described. Magnetic sensor 1
The target 20c to which A, 2A, 1B, and 2B face is
As described above, each target plate 2a has a thickness substantially the same as that of the target plate 2a coaxially externally fixed to the input shaft 31 and the output shaft 32, and is a protrusion protruding from the outer peripheral surface of the target plate 2a. Inclined in one direction from the circumferential direction of the plate 2a,
An inclined surface 20d parallel to the rotation axis of the target plate 2a and an inclined surface 20e inclined in the other direction from the circumferential direction of the target plate 2a and parallel to the rotation axis of the target plate 2a are provided. It is a magnetic body arranged in parallel in the circumferential direction of the surface. Each of the inclined surfaces 20d and 20e has a substantially plane-symmetric relationship with respect to a plane including the intersection of the two inclined surfaces 20d and 20e and the rotation axis of the target plate 2a.

Therefore, when the input shaft 31 and the output shaft 32 rotate around the axis, each of the magnetic sensors 1A, 2A, 1B, 2
B changes its distance from the corresponding inclined surface 20d or the inclined surface 20e of the target 20c, and the detection signal V1 of those signals changes.
As shown in FIG. 6, A, V2A, V1B, and V2B generate detection signals having isosceles triangular waveforms that rise and fall in proportion to changes in the rotation angles of the input shaft 31 and the output shaft 32. Output.

The detection signals of the magnetic sensors 1A and 1B are transmitted to the input shaft 31 provided with the corresponding target 20c.
Of the magnetic sensors 2A and 2A.
The detection signal B corresponds to the rotation angle of the output shaft 32 provided with the target 20c opposed thereto. Therefore, the arithmetic processing unit 4 can calculate the rotation angle of the input shaft 31 from the detection signals of the magnetic sensors 1A and 1B, and the arithmetic processing unit 4 and the magnetic sensors 1A and 1B
It operates as one rotation angle detection device. Further, the arithmetic processing unit 4 outputs the output shaft 3 from the detection signals of the magnetic sensors 2A and 2B.
2, the arithmetic processing unit 4 and the magnetic sensors 2A and 2B operate as a rotation angle detection device for the output shaft 32.

When a rotational torque is applied to the input shaft 31,
A deviation occurs between the detection signals V1A and V2A of the magnetic sensors 1A, 1B, 2A and 2B and between the detection signals V1B and V2B. However, the magnetic sensors 1A and 2A and the magnetic sensors 1B and 2B have a phase difference of, for example, an electrical angle of 90 ° in the circumferential direction of the target plate 2a, and the detection signals V1A and V1B are opposed to the magnetic sensors 1A and 1B. Slope 2
The regions where 0d and 20e alternate can be complemented with each other, and the same applies to the detection signals V2A and V2B.

Here, the detection signal V1A and the detection signal V2A
Or the difference between the detection signal V1B and the detection signal V2B corresponds to the difference in the rotation angle (relative angular displacement) between the input shaft 31 and the output shaft 32. This relative angular displacement is caused by the input shaft 3 under the action of the rotational torque applied to the input shaft 31.
This corresponds to the torsion angle generated in the torsion bar 34 connecting the output shaft 1 and the output shaft 32. Therefore, the rotation torque applied to the input shaft 31 can be calculated based on the difference between the detection signals described above.

[0042]

According to the rotation angle detecting device according to the first aspect of the present invention, it is possible to realize a rotation angle detecting device which has a simple structure and does not require the skill of an operator for the adjusting operation.

According to the rotation angle detection device according to the second aspect of the invention, a detection signal output from the detection means is stable, the structure is simple, and the rotation angle detection device does not require the skill of an operator for the adjustment operation. You can do it.

According to the rotation angle detection device according to the third aspect of the invention, a detection signal output from the detection means is stable, the structure is simple, and the rotation angle detection device does not require the skill of the operator for the adjustment operation. You can do it.

According to the rotation angle detection device according to the fourth aspect of the invention, it is possible to realize a rotation angle detection device that has good detection sensitivity, has a simple structure, and does not require the skill of an operator for the adjustment operation.

According to the rotation angle detecting device according to the fifth aspect of the present invention, it is possible to realize a rotation angle detecting device which has a low component cost, a simple structure, and does not require the skill of an operator for the adjusting operation.

According to the torque detecting device of the sixth aspect,
By using a rotation angle detection device that has a simple structure and does not require the skill of an operator for the adjustment operation, a torque detection device that can detect the steering angle can be realized.

According to the steering device of the seventh aspect, the steering device has a simple structure, does not require the skill of an operator for the adjusting operation, and includes the torque detecting device capable of detecting the steering angle. Can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic diagram schematically showing a configuration of an embodiment in which a rotation angle detection device and a torque detection device according to the present invention are applied to a steering device of an automobile.

FIG. 2 is a plan view showing a configuration of a target plate and a target.

FIG. 3 is a waveform chart showing an example of a detection signal of the rotation angle detection device according to the present invention.

FIG. 4 is a schematic diagram schematically showing a configuration of an embodiment in which a rotation angle detection device and a torque detection device according to the present invention are applied to a steering device of an automobile.

FIG. 5 is a plan view showing a configuration of a target plate and a target.

FIG. 6 is a waveform chart showing an example of a detection signal of the rotation angle detection device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor box 1A, 1B, 2A, 2B Magnetic sensor (detection means) 2, 2a Target plate (rotary body) 3 Steering axis 4 Arithmetic processing unit 20, 20c Target 20a Slope 20d First slope 20e Second slope 30 Steering wheel (steering wheel) 31 Input shaft 32 Output shaft 34 Torsion bar

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G01D 5/245 G01D 5/245 R G01L 5/22 G01L 5/22 F term (reference) 2F051 AA01 AB05 BA03 2F063 AA34 AA35 AA36 BA08 BB03 BB05 BC06 BD05 BD16 CA40 CB03 CB08 DA01 DA05 DB07 DC04 DD03 DD05 EA03 GA52 GA67 GA68 GA69 GA70 ZA01 2F069 AA86 AA88 AA99 BB21 BB40 DD25 DD26 DD30 FF00 GG04 GG04 GG06 GG52 GG63 GG01 GG65 GG03 GG65 H0309 CA16 CA28 CA29

Claims (7)

[Claims] 1. A rotating body, a target provided on the rotating body, and a part for detecting a part close to the target so that a part to be detected changes continuously as the rotating body rotates. A rotation angle detection device comprising: a plurality of detection means; and detecting a displacement angle in a rotation direction of the rotating body based on a part detected by the detection means, wherein the target includes one or more of the parts. Having a surface, and a protruding portion protruding from the peripheral surface of the rotating body,
The rotation angle detection device according to claim 1, wherein the detection unit is configured to output a detection signal according to a distance from the surface. 2. The surface has a first inclined surface inclined in one direction from the circumferential direction of the rotating body, and a second inclined surface provided in a different direction from the circumferential direction of the rotating body. The rotation angle detection device according to claim 1, wherein the rotation angle detection device is a surface. 3. The rotation angle detection according to claim 2, wherein the first inclined surface and the second inclined surface have a substantially plane-symmetric relationship with respect to a plane including an intersection line of the two inclined surfaces and a rotation axis of the rotating body. apparatus. 4. The rotation angle detecting device according to claim 1, wherein a plurality of the targets are provided continuously along a peripheral surface of the rotating body. 5. The rotation angle detecting device according to claim 1, wherein said target is a magnetic material, and said detecting means is a magnetic sensor. 6. A torque detecting device for detecting a torque applied to an input shaft by a torsion angle generated in a torsion bar coaxially connecting the input shaft and the output shaft, wherein a displacement angle of each of the input shaft and the output shaft is determined. A rotation angle detecting device according to any one of claims 1 to 5, wherein the rotation angle detecting device detects a difference between displacement angles detected by the rotation angle detecting device, and a difference between the displacement angles detected by the means. Is set as the torsion angle. 7. An input shaft connected to a steered wheel, an output shaft connected to a steering mechanism, a torsion bar connecting the input shaft and the output shaft, and a steering torque applied to the input shaft, A steering device comprising: the torque detection device according to claim 6, wherein the torque is detected by a torsion angle generated in a torsion bar.