JP4839933B2 - Rotation angle detector - Google Patents

Description

  The present invention relates to a rotation angle detection device mainly used for detecting a rotation angle of a steering wheel of an automobile.

  2. Description of the Related Art In recent years, as automobiles have become more sophisticated, in order to perform various controls such as braking and skidding prevention, the number of devices that detect the rotation angle of a steering using various rotation angle detection devices is increasing.

  Such a conventional rotation angle detection device will be described with reference to FIG.

  FIG. 8 is a perspective view of a main part of a conventional rotation angle detecting device. In FIG. 8, reference numeral 1 denotes a rotating body having a spur gear portion 1A formed on the outer periphery, and a steering (not shown) inserted through the central portion. An engaging portion 1B that engages with the shaft is provided.

  In addition, 2 is a first detection body in which a spur gear portion 2A having 1/3 teeth is formed on the outer periphery, and 3 is the number of teeth on the outer periphery. The spur gear portion 2A of the first detector 2 is meshed with the spur gear portion 1A of the rotating body 1 and the second detector 3 of the second detector 3 is formed. The spur gear portion 3A meshes with the spur gear portion 2A of the first detector 2.

  The first and second detectors 2 and 3 are provided with semicircular through holes 2B and 3B, respectively, and a plurality of light-emitting elements 4A and 4B are disposed above them, and substantially below these. Each of the wiring boards 5 is arranged in parallel, and a plurality of wiring patterns (not shown) are formed on both surfaces of the wiring board 5.

  Furthermore, 6A and 6B are 360 light emitting elements in which a plurality of photosensors and the like are arranged in a ring shape at intervals of 1 degree. The annular light emitting elements 6A and 6B are the first and second detectors 2 and 3 below. The control means 7 connected to the light emitting elements 4A and 4B and the annular light receiving elements 6A and 6B is formed on the wiring board 5 by electronic parts such as a microcomputer. A rotation angle detection device is configured.

  In such a rotation angle detecting device, the control means 7 is connected to an electronic circuit (not shown) of the automobile body through a connector (not shown) or the like, and is connected to the engaging portion 1B at the center of the rotating body 1. The steering shaft is inserted into the vehicle.

  In the above configuration, when the steering wheel is rotated, the rotating body 1 is rotated accordingly, and the first detecting body 2 and the first detecting body 2 in which the spur gear portion 2A meshes with the outer spur gear portion 1A. The second detectors 3 meshed with the spur gear portion 3A rotate in conjunction with each other.

  Further, the upper light emitting elements 4A and 4B emit light, and this light passes through the semicircular through holes 2B and 3B of the first and second detectors 2 and 3, and this light is received in the lower annular light reception. Elements 6A and 6B receive light.

  At this time, the annular light receiving elements 6A and 6B in which a plurality of photosensors are arranged in a ring shape at intervals of 1 degree are within a range corresponding to the rotational positions of the semicircular through holes 2B and 3B, for example, 0 degrees. The light from the light emitting elements 4A and 4B is received within a range from 180 degrees to 180 degrees, or from 90 degrees to 270 degrees, and this signal is output to the control means 7.

  From this signal, the control means 7, for example, when the signal from the annular light receiving element 6A is in the range of 0 degrees to 180 degrees, the rotation angle of the first detector 2 is 90 degrees, When the angle is in the range of 270 degrees to 270 degrees, it is detected that the rotation angle is 180 degrees.

  Similarly, a signal in the angular range is also output from the annular light receiving element 6B to the control means 7. However, since the first detector 2 and the second detector 3 have different numbers of teeth, the angular range The signal is also different.

  Then, the control means 7 calculates the different rotation angles from the annular light receiving elements 6A and 6B and the number of teeth of the rotating body 1, the first detecting body 2 and the second detecting body 3, whereby the rotating body 1 The rotation angle of the steering wheel, that is, the rotation angle of the steering wheel is detected.

As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
JP 2005-3625 A

  However, in the conventional rotation angle detection device, a plurality of light emitting elements 4A are respectively provided above and below the first detection body 2 meshed with the rotation body 1 and the second detection body 3 meshed with the first detection body 2. 4B and the annular light emitting elements 6A and 6B are arranged to detect the rotation angle, so that the number of components is large and the configuration is complicated and expensive.

  The present invention solves such a conventional problem, and an object of the present invention is to provide an inexpensive rotation angle detection device that can detect a rotation angle with high resolution and has a simple configuration.

To accomplish the above object, a first detection member that rotates in conjunction with the rotating body, and rotates in conjunction with the rotating body above the first detector and the rotation speed is different second detection The light emitting element above and the annular light receiving element below, respectively, two shielding portions provided at diagonal positions of the first detector, and the second The rotation angle detection device is configured such that the control means detects the rotation angle of the rotating body from the light receiving range of the annular light receiving element by the shielding portion provided at a position different from the first detecting body of the detecting body. Yes, since only one light emitting element and one annular light receiving element are provided above and below the first and second detectors, the number of components is small, an apparatus can be formed at a low cost, and a simple configuration with high resolution. When a rotation angle detection device capable of detecting an appropriate rotation angle can be obtained Cormorant is expected to have an effect.

  As described above, according to the present invention, it is possible to detect a rotation angle with high resolution, and to obtain an advantageous effect that an inexpensive rotation angle detection device can be realized with a simple configuration.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

(Embodiment)
FIG. 1 is a perspective view of a main part of a rotation angle detecting device according to an embodiment of the present invention, in which 11 is a rotating body made of insulating resin or metal having a spur gear portion 11A formed on the outer periphery. The central portion is provided with an engaging portion 11B that engages with a shaft of a steering (not shown) to be inserted.

  Reference numeral 12 denotes a first detection body in which a spur gear portion 12A having a number of teeth of 1/3 of the number of teeth of the rotating body 11 is formed on the outer periphery, and reference numeral 13 denotes the first detection body 12 on the outer periphery. In the second detection body in which different spur gear portions 13A are formed, the first detection body 12 and the second detection body 13 are arranged one above the other, and these spur gear portions 12A and 13A are rotating bodies. 11 spur gears 11A.

  Furthermore, in the hollow hole 12B of the first detection body 12, a shielding part 12C projecting inward within a range of 90 to 130 degrees and a shielding part 12D projecting inward within a range of 230 to 270 degrees are provided. Two shielding portions are provided at diagonal positions, and unlike the shielding portions 12C and 12D, the hollow holes 13B of the second detection body 13 project inward at a position of 0 degrees orthogonal to them. A shielding part 13C is provided.

  Reference numeral 14 denotes a light emitting element such as a light emitting diode disposed above the hollow holes of the first and second detection bodies 12 and 13, and 15 denotes a rotating body 11 and the first and second detection bodies 12 and 13 on the lower surface. A plurality of wiring patterns (not shown) are formed on both surfaces of the wiring board 15 in the wiring boards arranged in parallel.

  Further, reference numeral 16 denotes an annular light emitting element in which a plurality of photosensors and the like are arranged in a ring shape at intervals of 1 degree. The annular light emitting element 16 is a wiring substrate 15 below the first and second detectors 12 and 13. A control means 17 connected to the light emitting element 14 and the annular light receiving element 16 is formed on the wiring board 15 by an electronic component such as a microcomputer.

  The lower surfaces of the first detection body 12 and the second detection body 13 are formed with hollow cylindrical rotating cylinders 12E and 13D protruding downward, and the rotating cylinder 12E is a rotation groove on the upper surface of the annular light receiving element 16. In 16A, the rotating cylinder 13D is rotatably inserted into the rotating groove 12F on the upper surface of the first detection body 12 to constitute a rotation angle detecting device.

  Further, in such a rotation angle detecting device, the control means 17 is connected to an electronic circuit (not shown) of the automobile body through a connector, a lead wire (not shown), etc., and the center of the rotating body 11 is engaged. A steering shaft is inserted into the part 11B and is attached to the automobile.

  In the above configuration, when the steering is rotated, the rotating body 11 is rotated accordingly, and the first detecting body 12 and the second detecting body in which the spur gear portions 12A and 13A are engaged with the outer spur gear portion 11A. 13 also rotates.

  The upper light emitting element 14 emits light, and this light passes through the hollow holes 12B and 13B of the first and second detectors 12 and 13, and the lower annular light receiving element 16 receives the light. In the state of 0 degree before the first and second detection bodies 12 and 13 rotate, as shown in the plan view of FIG. 2A, the hollow portion 12B of the first detection body 12 has a shielding portion 12C. And 12D are provided, so that light in the range of 90 to 130 degrees and 230 to 270 degrees is blocked, and the annular light receiving element 16 has other than this as shown in the waveform diagram of FIG. Receive light in the range.

  Further, as shown in FIG. 2 (b), since the shielding portion 13C is provided at the 0 degree position in the hollow hole 13B of the second detection body 13, the light at this position is also blocked, and the annular light reception is performed. The element 16 receives the range as shown in FIG. 3B, and as a result, the light within the range of the shielding portions 12C, 12D, and 13C as shown in FIG. The signal is output to the control means 17.

  Then, from this signal, the control means 17 detects that the position of the blocking part 13C is at the center between the 270 degrees and 90 degrees of the shielding parts 12D and 12C, and the received light range of 180 degrees, and 230 degrees. The center of 130 degrees and 0 degree are detected as the rotation angle.

  Further, when the rotating body 11 rotates 30 degrees and the first detection body 12 whose number of teeth is 1/3 of the rotating body 11 rotates 90 degrees accordingly, the plan view of FIG. As shown, the light from the light emitting element 14 is blocked from 320 degrees to 0 degrees and from 180 degrees to 220 degrees by the shielding portions 12C and 12D of the first detection body 12, and the annular light receiving element 16 is A range as shown in the waveform diagram of FIG.

  Similarly, the light from the light emitting element 14 is also blocked by the shielding portion 13C of the second detection body 13, but the second detection body 13 has a different number of teeth from the first detection body 12. In the state where the first detection body 12 is rotated by 90 degrees, as shown in FIG. 4B, the second detection body 13 rotates, for example, only 81 degrees, which is 9 degrees smaller than this, and the annular light receiving element 16 5B receives a range where light of about 81 degrees is blocked as shown in FIG. 5B, and as a result, a signal as shown in FIG. Is output.

  Then, from this signal, the control means 17 detects that the position of the shielding part 13C is at a position deviated from the center between the received light range 180 degrees between 0 degrees and 180 degrees of the shielding parts 12C and 12D. , 90 degrees of the center of 320 degrees and 220 degrees is detected as the rotation angle.

  Further, when the rotating body 11 is rotated 120 degrees and the first detection body 12 is rotated 360 degrees, as shown in the plan view of FIG. ), The light in the range of 90 degrees to 130 degrees and 230 degrees to 270 degrees is blocked. As shown in the waveform diagram of FIG. The same range as in FIG. 3A is received.

  However, since the second detection body 13 has a different number of teeth from the first detection body 12 as described above, the second detection body 13 rotates, for example, only 324 degrees, which is 36 degrees less than this, and is annular. The light receiving element 16 receives a range where light of about 324 degrees is blocked as shown in FIG. 7B, and as a result, a signal as shown in FIG. The

  Then, from this signal, the control means 17 detects that the position of the shielding part 13C is at a position that is 36 degrees away from the center of the received range 180 degrees between the 270 degrees and 90 degrees of the shielding 12D and 12C. Thus, it is determined that the first detection body 12 has rotated 360 degrees instead of 0 degrees, that is, 1 rotation, and 0 degrees at the center of 230 degrees and 130 degrees is determined to be 360 degrees, and the rotation angle is 360 degrees. To detect.

  That is, the position of the shielding part 13C of the second detection body 13 is anywhere between 180 degrees which is the light receiving range of the shielding parts 12C and 12D provided at the diagonal positions of the first detection body 12. Accordingly, the number of rotations of the first detection body 12 is detected, and the center between 230 degrees and 130 degrees in a wider range is detected as the rotation angle.

  That is, the shielding portions 12C and 12D provided at diagonal positions 180 degrees apart from the first detection body 12 and the shielding portions 13C provided at a position of 0 degrees perpendicular to these of the second detection body 13 From the positional relationship, the control means 17 detects the number of rotations of the first detection body 12, so that only one light emitting element 14 and the annular light receiving element 16 arranged above and below the first and second detection bodies 12, 13. Thus, the absolute angle of the rotating body 11 can be detected.

  At this time, as described above, since the annular light receiving element 16 is formed by arranging a plurality of photosensors in a ring shape at intervals of 1 degree, the annular light receiving element 16 is spaced at an interval of 1 degree with respect to the rotation of the detection body 12. The rotation angle at can be detected.

  Furthermore, as described above, the number of teeth of the detection body 12 is 1/3 of the number of teeth of the rotation body 11, and the detection body 12 rotates three times for one rotation of the rotation body 11. With respect to the rotation angle of 11, the high resolution rotation angle of about 0.33 degrees, which is obtained by dividing 1 degree of resolution of the rotation angle of the detection body 12 by 3, can be detected.

According to this embodiment, first the first detection member 12 that rotates in conjunction with the rotary body 11, is rotated in conjunction with rotation member 11 and the first detection member 12 rotation speed different The two detectors 13 are arranged so as to overlap each other, the light emitting element 14 is disposed above the two detectors, and the annular light receiving element 16 is disposed below the two detectors. The control means 17 rotates the rotating body 11 from the light receiving range of the annular light receiving element 16 by the shielding portions 13C provided at different positions from the shielding portions 12C and 12D and the first detection body 12 of the second detection body 13. By detecting the angle, only one light emitting element 14 and one annular light receiving element 16 are required. Therefore, the number of components can be reduced, an apparatus can be formed at a low cost, and a simple structure can be used to detect a rotation angle with high resolution. Possible rotation angle detector It is intended.

  In the above description, a spur gear portion is formed on the outer periphery of each of the rotating body 11, the first detecting body 12, and the second detecting body 13, and these are meshed to rotate in conjunction with each other. However, in addition to the spur gear portion, a configuration using a gear of another shape such as a bevel gear, or an uneven portion or a high friction portion capable of transmitting rotation instead of the gear is provided on the outer periphery of the rotating body or each detecting body. It is possible to implement the present invention even if they are formed and rotated in conjunction with each other.

  The rotation angle detection device according to the present invention can detect a rotation angle with high resolution, can be realized with a simple configuration, and can be realized at low cost, and is mainly useful for detection of a rotation angle of a steering wheel of an automobile.

The principal part perspective view of the rotation angle detection apparatus by one embodiment of this invention Plan view Waveform diagram Plan view Waveform diagram Plan view Waveform diagram Main part perspective view of a conventional rotation angle detection device

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Rotating body 11A, 12A, 13A Spur gear part 11B Engaging part 12 1st detection body 12B, 13B Hollow hole 12C, 12D, 13C Shielding part 12E, 13D Rotating cylinder 12F, 16A Rotating groove 13 2nd detection body 14 Light emitting element 15 Wiring board 16 Annular light receiving element 17 Control means

Claims (1)

A rotating body that rotates in conjunction with steering, a first that rotates in conjunction with the rotating body and the detector, and rotates in conjunction with the rotating body above the first detector and the rotation speed is different second A detector, a light emitting element disposed above the first and second detectors, an annular light receiving element disposed below the first and second detectors, and the light emitting element and the annular light receiving element The first detection body and the second detection body each have a hollow hole and are arranged one above the other so as to overlap the hollow hole of the first detection body. Two shielding portions projecting inward are provided at diagonal positions, and a shielding portion projecting inward at a position different from the two shielding portions is provided in the hollow hole of the second detection body, and the control means Rotation that detects the rotation angle of the rotating body from the light receiving range of the annular light receiving element Degree detection device.

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