JP3343197B2 - Encoder cleaning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission type encoder for detecting an amount of movement of an object to be detected by blocking an optical path passing through a slit of the moving body with movement of the moving body. The present invention relates to a cleaning device for an encoder for removing dust and the like adhering to a slit.

[0002]

2. Description of the Related Art As a conventional optical transmission type encoder,
A linear moving body 50 shown in FIG. 5 or a rotary moving body 51 shown in FIG. 6 fixed to an object (not shown) as shown in FIGS. Some slits 52 are formed at predetermined intervals along the gap, and light from a light emitting unit (not shown) is transmitted through the slit 52 and enters a light receiving unit (not shown). That is, the encoder detects the movement amount of the detection target by blocking the optical path 53 that passes through the slit 52 of the moving bodies 50 and 51 as the moving bodies 50 and 51 move.

[0003] As a specific example of the optical transmission type encoder, Japanese Patent Publication No. 4-54181 discloses an optical switch 60 provided with a light emitting element and a light receiving element, which is interlocked with a steering shaft 61 as shown in FIG. Disk 62
An automotive steering angular velocity sensor for detecting the movement of a vehicle is described. The disk 62 has a plurality of cutouts for transmitting light.

Further, as shown in FIG.
Japanese Patent Application Publication No. 565 discloses a rotation amount detection device including optical transmission encoders 70 and 71 for angle detection and rotation detection. Light emitting section 72 of each encoder 70, 71
Are transmitted through the slit 74 for detecting the angle and the slit 75 for detecting the rotation of the slit disk 73 and enter the light receiving section 76.

Further, as shown in FIG.
Japanese Patent No. 7506 describes a steering angle sensor that detects the rotation amount of a rotating disk 82 having a slit, which is interlocked with a steering shaft (not shown), that is, a steering rotation angle, using a light emitting diode 80 and a phototransistor 81. Light from the light emitting diode 80 passes through a slit of a rotating disk (not shown) and enters the phototransistor 81.

[0006]

However, in the above-mentioned conventional optical transmission type encoder, as shown in FIG. 7, when dust 54 adheres to the slits 52 of the moving bodies 50 and 51, the optical path 53 is blocked. The light from the light emitting unit cannot pass through the slit 52, and there is a problem that a large error occurs in the detection of the movement amount of the detection target.

SUMMARY OF THE INVENTION An object of the present invention is to provide an encoder cleaning device capable of reliably removing dust and the like adhering to a slit of a moving body and accurately and reliably detecting the amount of movement of an object to be detected by the encoder. To provide.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide a moving apparatus in which a plurality of slits are formed at predetermined intervals along the moving direction of an object to be detected, in conjunction with the object to be detected. An optical path that is provided on both sides of the body, and that has an optical path that passes through the slit, and that detects the amount of movement of the object by blocking the optical path with the movement of the movable body. An encoder provided with a detection means, rotatably provided near the moving body, provided with a plurality of projections at predetermined intervals along the circumferential direction of the outer peripheral surface and radially, The present invention can be solved by a cleaning device for an encoder, wherein a protrusion is sequentially inserted into the slit, and a rotating body that rotates in conjunction with the moving body is provided.

In the encoder cleaning device having the above-described configuration, the rotating body rotates in conjunction with the moving body while a plurality of projections projecting from the outer peripheral surface thereof are sequentially inserted into the slits of the moving body. Therefore, dust or the like adhering to the slit of the moving body can be reliably removed by the projection of the rotating body, and the movement amount of the object to be detected by the encoder can be detected accurately and reliably.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the cleaning device for an encoder according to the present invention will be described below in detail with reference to FIGS. FIG. 1 is a plan view showing a steering column portion showing an embodiment of an encoder cleaning device of the present invention, FIG. 2 is a sectional view taken along arrow A in FIG. 1, FIG. 3 is a sectional view taken along arrow B in FIG. FIG. 4 is a schematic sectional view of the cleaning device in FIG. As shown in FIGS. 1 to 3, the encoder 10 detects a rotation amount of a steering shaft (not shown), that is, a steering angle by optically detecting a rotation amount of the rotating disk 20 by the optical unit 30.

The rotating disk 20 is rotatably supported by the column switch 11 via the FFC section 21. The rotating disk 20 is attached to the outer peripheral surface of the steering shaft by fitting the steering shaft into the shaft hole 22.
The rotating disk 20 is rotated together with the FFC unit 21 in conjunction with the steering shaft. In addition, the rotating disk 20
Is formed with a large number of slits 23 for transmitting light at predetermined intervals along the rotation direction of the steering shaft.

The optical unit 30 is fixed to the column switch 11, and a light emitting element 31 and a light receiving element 32 are provided on both sides (upper and lower sides in FIG. 2) of the rotating disk 20. Optical path 33 that transmits light
Having. The optical unit 30 detects the rotation amount of the steering shaft by blocking the optical path 33 between the light emitting element 31 and the light receiving element 32 with the rotation of the rotating disk 20.

As shown in FIGS. 1, 3 and 4, the cleaning device 40 of the encoder 10 includes a gear-shaped rotating body 4.
1 reliably removes dust and the like adhering to the slits 23 of the rotating disk 20. That is, a pair of rotating bodies 41 are arranged in the vicinity of the rotating disk 20 with a phase difference of about 90 ° in a plan view with the optical unit 30 interposed therebetween, and a support projecting upward from the column switch 11 in FIG. The portion 12 is rotatably supported.

A plurality of projections 42 are provided on the outer peripheral surface of each rotating body 41 at predetermined intervals along the circumferential direction and project in the radial direction. Each of the rotating bodies 41 has the projection 42 inserted into each of the slits 23 of the rotating disk 20 sequentially, and rotates in conjunction with the rotating disk 20. As a result, each rotating body 41 is provided with a rotating disk 2
The dust or the like adhering to the 0 slit 23 is pushed out by the projection 42 and reliably removed.

In the above-described encoder cleaning device 40 of the present embodiment, the optical unit 30 includes the rotating disk 2.
When the rotation amount of the steering shaft, that is, the steering angle is detected by optically detecting the rotation amount of 0, each rotating body 4
One projection 42 is sequentially inserted into each slit 23 of the rotating disk 20. When the rotating body 41 rotates in conjunction with the rotating disk 20, dust or the like adhering to the slits 23 of the rotating disk 20 is pushed out by the projections 42 and reliably removed.

Accordingly, since each rotating body 41 causes the projection 42 to be sequentially fitted into the slit 23 of the rotating disk 20 and rotates in conjunction with the rotating disk 20, dust or the like adhered to the slit 23 of the rotating disk 20. Can be reliably removed. As a result, it is possible to accurately and reliably detect the rotation amount of the steering shaft, that is, the steering angle by the encoder 10.

In this embodiment, a pair of rotating bodies 4
Although the optical unit 1 is arranged so as to sandwich the optical unit 30 with a phase difference of about 90 ° in plan view, the number and the arrangement position of the rotating bodies 41 can be arbitrarily set in accordance with other members around the steering column.

[0018]

As described above, according to the encoder cleaning device of the present invention, a plurality of encoders are provided rotatably in the vicinity of the moving body, are spaced at a predetermined interval along the circumferential direction of the outer peripheral surface, and extend in the radial direction. Are provided, and the projections are sequentially inserted into the slits, and the rotating body is rotated in conjunction with the moving body. Therefore, the rotating body rotates in conjunction with the moving body while sequentially inserting a plurality of protrusions projecting from the outer peripheral surface into the respective slits of the moving body, so that dust and the like adhered to the slits of the moving body can be reliably removed. And the encoder can accurately and reliably detect the amount of movement of the object by the encoder.

[Brief description of the drawings]

FIG. 1 is a plan view showing a steering column portion to which an encoder to which an embodiment of an encoder cleaning device of the present invention is applied is attached.

FIG. 2 is a sectional view taken along the arrow A in FIG.

FIG. 3 is a sectional view taken along the arrow B in FIG. 1;

FIG. 4 is a schematic sectional view of a cleaning device of the encoder in FIG. 1;

FIG. 5 is a perspective view showing a linear moving body of a conventional encoder.

FIG. 6 is a perspective view showing a rotary moving body of a conventional encoder.

FIG. 7 is a sectional view showing a moving body of a conventional encoder.

FIG. 8 is a partial cross-sectional view illustrating a steering angular velocity sensor for an automobile, which is an example of a conventional encoder.

FIG. 9 is a perspective view showing a rotation amount detection device as another example of the conventional encoder.

FIG. 10 is a cross-sectional view showing a steering angle sensor as still another example of the conventional encoder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Encoder 11 Column switch 12 Support part 20 Moving body (rotating disk) 23 Slit 30 Optical detecting means (optical unit) 31 Optical detecting means (light emitting element) 32 Optical detecting means (light receiving element) 33 Optical path 40 Cleaning device 41 Rotating body 42 Projection

Claims (1)

(57) [Claims] A moving body having a plurality of slits formed at predetermined intervals along a moving direction of the detected object, and provided on both sides of the moving body. An optical path having an optical path that passes through the slit, and an optical detection unit that detects an amount of movement of the object to be detected by blocking the optical path with the movement of the moving body. A plurality of protrusions are provided rotatably in the vicinity, at predetermined intervals along the circumferential direction of the outer peripheral surface, and are provided in the radial direction, and the protrusions are sequentially inserted into the slits. An encoder cleaning device comprising a rotating body that rotates in conjunction with the moving body.