JPH1019555A - Rotation angle detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enlarge the resolution per distance (sliding change amount) and to obtain a stable rotation angle detection. SOLUTION: A spindle 1, a substrate on which a spiral part 3 which encloses the spindle 1 and is so provided that free rotation is allowed by the spindle 1 is formed, and a straight line displacement detecting device 6 comprising an operation piece 6b are provided. The straight line displacement detecting device 6 is so assigned that the moving direction of the operation piece 6b is deviated from the axis center of the spindle 1, and the spiral part 3 of the substrate is made to engage with an engagement part provided to the operation piece 6b of the detecting device 6, for driving the operation piece 6b according to the rotation of the spindle 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation angle detecting device used for detecting a steering angle of an automobile, for example.

[0002]

2. Description of the Related Art Conventionally, as this kind of rotation angle detecting device, there is one disclosed in, for example, Japanese Utility Model Laid-Open Publication No. Sho 60-56213. This configuration is a vehicle steering angle detection device, which will be described below with reference to the drawings.

FIG. 3 is a partial longitudinal sectional view showing a steering angle detecting device as one form of a conventional rotation angle detecting device, and FIG. 4 is a plan view for explaining the same. In the figure, a rotating shaft 1 such as a steering shaft is directly connected to a handle (not shown), and is configured to make approximately two rotations (all four rotations) left and right in accordance with the rotation of the handle. A disk 2 is held on the rotating shaft 1 coaxially as a base, and the disk 2 has, for example, a spiral groove 3 as a spiral portion. A rotating shaft 1 is rotatably supported on the vehicle body fixed side (not shown) around an axis. A linear displacement detecting device 6, which is, for example, a linear (linear) variable resistor held by a bracket 4, is disposed on the vehicle body fixed side. The linear displacement detecting device 6 includes a resistor substrate (not shown) in which a resistor is formed on one surface of the case 7 by printing or the like, and a slider that slides on the resistor substrate along a longitudinal direction thereof. (Not shown), and a shaft-like operating element 9 integral with the slider receiver 8 protruding out of the case 7. The resistance value between one end (terminal) of the resistor formed on the resistance board and the slider housed in the slider receiver 8 corresponding to the sliding position of the slider receiver 8. Is output in an analog manner.

Further, the linear displacement detecting device 6 is arranged so that the bracket 4 allows the linear displacement detecting device 6 to be positioned in a linear direction passing through the axis of the rotating shaft 1 of the disk 2, that is, in a diametrical direction, and the tip of the operating element 9 to be moved. It is arranged to be inserted into the spiral groove 3 of the disk 2. Accordingly, the disk 2 is rotated by the rotation of the rotating shaft 1 such as a steering shaft, and the operator 9 is guided by the spiral groove 3 and slides in a direction crossing the spiral groove 3. Then, when the slider of the slider receiver 8 slides on the resistance substrate, the rotation angle of the rotating shaft 1 is detected as a change in the resistance value together with the direction of left rotation or right rotation,
These are output to the display unit 10 and displayed.

As shown in FIG. 4, when the rotation angle of the rotating shaft 1 is zero degree, the operation of the linear displacement detecting device 6 is substantially at the middle of the entire length of the disk 2 along the spiral groove 3. Child 9
, And at this time, the resistance value of the linear displacement detection device 6 is set in advance so as to be approximately an intermediate value of the total resistance value change. In this state, when the rotary shaft 1 is rotated clockwise, for example (arrow A), the slider 8 is guided by the spiral groove 3 of the disk 2 and slides on the resistor (arrow a). The resistance value of (1) sequentially increases (or decreases) from the resistance value of the intermediate portion, and this resistance value detects the rotation angle when the rotation direction is rightward. Further, when the user rotates the rotation shaft 1 leftward from the above-described state where the rotation angle is zero degrees (arrow B),
The slider 8 is guided by the spiral groove 3 and slides on the resistor in the opposite direction (arrow b), and the resistance value at this time sequentially decreases (or increases) from the intermediate portion resistance value. )
Then, this resistance value detects the rotation angle when the rotation direction is set to the left.

[0006]

However, in the above-described conventional rotation angle detecting device, the linear type linear displacement detecting device 6 which engages with the spiral groove 3 formed in the disk 2 has a diameter corresponding to the diameter of the disk 2. Therefore, the sliding length (distance L ′) of the slider of the linear displacement detecting device 6 cannot be sufficiently obtained due to the restriction due to the size of the disk 2. Therefore, when rotating the rotating shaft 1 in the left-right direction, the sliding distance L ′ of the slider of the linear displacement detecting device 6 that is interlocked with the rotation of the rotating shaft 1 is short. (A change in resistance value) cannot be obtained.

[0007]

According to the present invention, there is provided a rotary shaft, a base surrounding the rotary shaft and having a spiral portion rotatably provided by the rotary shaft, and a linear displacement detecting device provided with an operation element. And the linear displacement detection device is arranged such that the moving direction of the operation element is off the axis of the rotation shaft, and the spiral part of the base and the engagement part provided on the operation element of the detection device are provided. Engage with the rotation of the rotating shaft,
That is, the operator was driven.

[0008] The linear displacement detecting device is constituted by a variable resistor.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial longitudinal sectional view showing a rotation angle detecting device of the present invention, and FIG. 2 is a plan view for explaining the same. In the figure, a disk 2 serving as a base is held coaxially at an intermediate portion of a rotating shaft 1 such as a steering shaft. The spiral groove 3 is formed with a groove having a length that allows the rotating shaft 1 to make approximately five and a half rotations. The length of this groove is formed with a margin more than the rotation range of the rotating shaft 1. The disc 2 may be directly fixed to the rotating shaft 1 and rotated, but is not directly in contact with the rotating shaft, but is often rotated by a hub portion of a handle disposed near the upper end of the rotating shaft 1. . A base plate 12 for holding the linear displacement detecting device 6 of the present invention extends from a fixed side of the vehicle body or the like (not shown). A printed wiring board 11, which is a so-called motherboard, is held on the base plate 12, and the printed wiring board 11 is provided with a linear displacement detecting device 6 including, for example, a linear (linear) variable resistor. ing. The linear displacement detector 6
Is operated by the leg 6d.
A predetermined angle with respect to the center line (diameter of the disk 2) passing through the axis of the rotation shaft 1 of the disk 2 and the moving end of the operating element 6b so that the direction of movement of b does not pass through the axis of the rotation shaft 1. (Θ degrees). In the present embodiment, the linear type linear displacement detection device 6 is disposed at an angle of 35 degrees with respect to the diameter of the disk 2.

The linear displacement detecting device 6 includes a resistor substrate 6a having a resistor (not shown) formed on one surface thereof by printing or the like in a case 6f, and a resistor body (not shown) formed on the resistor substrate 6a along the longitudinal direction. A slider receiver 6c having a sliding slider (not shown) is provided, and a shaft-like operating element 6b integral with the slider receiver 6c protruding out of the case 6f. . The slider of the slider receiver 6c, which is held when the operator 6b is driven by the rotation of the rotating shaft, is engaged with the tip of the operator 6b as an engagement portion with the spiral groove 3. It slides on the resistance substrate 6a. The terminal 6e is connected to the resistance substrate 6a
The linear displacement detector 6 is electrically connected to the upper resistor.
The resistance substrate 6a corresponds to the sliding position of the slider receiver 6c.
Of the resistance between one end of the slider and the slider housed in the slider receiver 6c is output from the terminal 6e in an analog manner. As described above, the linear displacement detection device 6 has a configuration equivalent to a so-called general slide type variable resistor.

The accuracy (resolution) of the linear displacement detecting device 6
In order to improve the sliding distance, it is necessary to increase the sliding distance L of the slider of the slider receiver 6c as much as possible. For this reason, in the embodiment of the present invention, the linear type linear displacement detecting device 6 is disc-shaped so that the moving direction of the operation element 6b of the linear displacement detecting device 6 does not pass through the axis of the rotary shaft 1. 2 is inclined at a predetermined angle (θ degrees) with respect to the diameter direction (OX). As described above, the linear displacement detecting device 6 is set at a predetermined angle (θ
(Degree), the linear displacement detecting device 6 having a longer sliding distance L by 1 / COSθ can be used as compared with the conventional disk 2 disposed at a position having the diameter of the disk 2. For example, when the inclination angle (θ degree) is 35 degrees, the sliding distance L can be 1.221 times longer than the zero inclination degree. This means that if a conventional variable resistor having a sliding stroke of 12 mm, for example, is arranged at an angle of 35 degrees, the sliding stroke can be extended to 14.65 mm. Therefore, since the sliding stroke of the slider can be lengthened,
A large resolution per sliding distance can be obtained.

When the linear displacement detection device 6 is disposed at a predetermined angle (θ degrees), the rotation angle of the rotary shaft 1 and the sliding position of the slider in the slider receiver 6c are determined. In relation to each other, the sliding distance per rotation angle becomes longer as the slider is located closer to the center of the disk 2. However, the point that the change in the resistance value per rotation angle is not linear is that the resistance characteristic curve of the resistor on the resistance substrate 3a constituting the linear displacement detection device 6 corresponds to the inclination at a predetermined angle (θ degrees). It can be corrected by using a characteristic curve. This resistance characteristic curve can be generally formed by a basic method in the manufacture of a variable resistor.

Next, the operation will be described.
As shown in FIG. 2, when the rotation angle of the rotation shaft 1 is zero degree,
The operator 6b of the linear displacement detection device 6 is located at substantially the middle of the entire length of the disk 2 along the spiral groove 3, and the resistance value from the linear displacement detection device 6 is approximately the middle of the total resistance value change. It is set in advance so as to be a value. From this state,
For example, when the rotary shaft 1 is rotated clockwise (arrow A) by operating the rotary shaft 1, the operator 6 b interlocked with the slider receiver 6 c is moved to the disk 2.
Is guided on the spiral groove 3 and slides on the resistance substrate 6a (arrow a), and the resistance value at this time sequentially increases (or decreases) from the resistance value at the intermediate portion, and this resistance value is shifted rightward in the rotation direction. Detect the rotation angle when the direction is set. When the rotary shaft 1 is rotated leftward by the operation of the rotary shaft 1 from the above-described state where the rotation angle is zero degree (arrow B), the operator 6b interlocked with the slider receiver 6c is guided by the spiral groove 3 and The slider slides on the resistor substrate 6a in the opposite direction (arrow b), and the resistance value at this time sequentially decreases (or increases) from the intermediate portion resistance value, and the resistance value is such that the rotation direction is the left direction. The rotation angle at the time is detected.

As described above, the operation element 6b is guided by the spiral groove 3 by the rotation of the rotating shaft 1 such as a steering shaft, and slides in the direction crossing the spiral groove 3 at an inclined angle. When the slider of the slider receiver 6c slides on the resistance substrate 3a, the rotation angle of the rotating shaft 1 is detected as a change in resistance value together with the right or left rotation direction. Is output to, for example, the display unit 10 and displayed.

The linear displacement detector 6 is not limited to the variable resistor according to the embodiment of the present invention, but may be a linear optical encoder or a linear magnetic encoder. The optical encoder uses an optical scale (parallel slit) and an optical light emitting / receiving element instead of a resistive substrate and a slider, and the magnetic encoder uses a magnetic scale and a magnetoresistive element to detect the above. Becomes In the case of using an optical encoder or a magnetic encoder, the correction for the inclination at a predetermined angle (θ degrees) can be performed by using a correction scale or by performing an operation (eg, processing on program software). In the former case, the correction process is performed by adjusting the shape of the slit. In the latter case, the correction process is performed, for example, by comparing and correcting digital signals from each encoder using a ROM table or the like.

Further, in the embodiment of the present invention, the spiral part is described as the spiral groove 3, but the spiral part is not limited to the groove shape. For example, the spiral part may be a convex part. In the case of this convex shape, the tip of the operation element 6b may be formed in a concave shape, and the concave and the convex may be engaged.
Further, in the embodiment of the present invention, a disk is used as a base on which the spiral portion is provided, but the disk is not limited to the disk, and may be a polygonal shape or an elliptical shape. Further, in the embodiment of the present invention, the distal end of the operation element 6b is an engagement part with the spiral groove, but the engagement part is a separate member.
b and may be engaged with the spiral groove. Furthermore, in the embodiment of the present invention, one end of the detecting device 6 is on the straight line OX in the diameter direction of the disk, but the present invention is not limited to this. This operation can also be performed if the operating element 6b is driven by the spiral groove 3 even if the moving direction of the operator is on an offset straight line parallel to the straight line OX.

[0017]

As described above, when the rotation angle is detected, the linear type detection device is set at a predetermined angle (θ) with respect to the diameter of the disk.
), The sliding distance L of the slider held by the slider receiver can be made longer than before. Therefore, the resolution per distance can be increased,
A stable rotation angle can be detected.

Since the detection device is a variable resistor,
The resistance change characteristic curve of the resistor can be easily set to a desired one. Therefore, even if the variable resistor is arranged at a predetermined angle with respect to the diameter of the disk, the inclination of the resistor of the detecting device can be corrected by setting the resistance change characteristic curve of the resistor. Since other members are not required, the configuration can be made inexpensively.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional view showing a rotation angle detecting device of the present invention.

FIG. 2 is a plan view for explaining a rotation angle detection device according to the present invention.

FIG. 3 is a partial longitudinal sectional view showing a steering angle detection device according to one form of a conventional rotation angle detection device.

FIG. 4 is a plan view for explaining a steering angle detection device according to one form of a conventional rotation angle detection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotation axis 2 Disk 3 Spiral groove 6 Linear displacement detection device 6a Resistance board 6b, 9 Operator 6c, 8 Slider receiver 6e Terminal 6f, 7 Case 11 Printed wiring board

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ryo Totsuka 1-7 Yukitani Otsukacho, Ota-ku, Tokyo Alps Electric Co., Ltd. (72) Inventor Yukari 1-7 Yukitani Otsukacho, Ota-ku, Tokyo Alp SU Electric Co., Ltd.

Claims (2)

[Claims] A rotary shaft, a base surrounding the rotary shaft and having a spiral portion rotatably provided by the rotary shaft, and a linear displacement detection device provided with an operation element; The linear displacement detection device is disposed so that the moving direction of the operation element is out of the axis of the rotation shaft, and the spiral portion of the base is engaged with an engagement portion provided on the operation element of the detection device. A rotation angle detection device, wherein an operation element is driven in accordance with the rotation of the rotation shaft. 2. The rotation angle detection device according to claim 1, wherein the linear displacement detection device is a variable resistor.