JPH052020U - Bearing structure for hollow shaft encoder - Google Patents

Abstract

(57) [Abstract] [Object] The present invention relates to a bearing structure for a hollow shaft encoder, and in particular, prevents oil splashing on a rotary slit disk by removing oil splashing from the bearing with an oil cutout. It is characterized by [Structure] The bearing structure for the hollow shaft encoder according to the present invention is
A base (1) and a hollow rotary shaft (9) rotatably provided on first and second bearings (4, 7) provided on a support (6) separate from the base (1) A first oil cutout body (11) located at one end side (4A) of the first bearing (4) and a second oil cutout body (12) located at one end side (7A) of the second bearing (7). ), A rotary slit disk (10) provided on the outer periphery of the hollow shaft (9), and the rotary slit disk.
(10) is provided with a light-receiving body (8) and a light-emitting body (2) provided so as to be opposed to each other, and the oil drainers (11, 12) are provided on the hollow shaft (9). .

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a bearing structure for a hollow shaft encoder, and more particularly to a novel improvement for preventing oil from scattering on a rotary slit disk by removing a shaft scattered from the bearing with an oil cutout.

[0002]

[Prior Art]

 There are various conventional bearing structures for hollow shaft encoders of this type, and a typical one of them is disclosed in Japanese Patent Application Laid-Open No. 2-40509 shown in FIG. The configuration can be mentioned. That is, the reference numeral 1 in the drawing is a base having a light emitting body 2, and a bearing hole 3 of the base 1 is provided with a first bearing 4. A support 6 is fixed above the base 1 through a support wall 5 provided on the base 1. The support 6 includes a first support 6a and a second support. It is composed of a part 6b. A second bearing 7 is provided on the inner wall 6aA of the first support portion 6a, and a light receiving body 8 is provided on the second supporting body portion 6b corresponding to the light emitting body 2. A hollow shaft 9 having a pair of oil cut bodies 11 and 12 is rotatably provided on each of the inner rings 4a and 7a of each of the bearings 4 and 7, and the hollow shaft 9 includes a guide hole 1a and a guide hole 1a of the base 1. Further, they penetrate the guide holes 6A of the first support portion 6A and project outwardly. Therefore, the rotation of the hollow shaft 9 causes the rotation slit disk 10 provided on the hollow shaft 9 to rotate, so that the light from the light emitting body 8 passes through the slit (not shown) of the rotation slit disk 10. The rotation state of the hollow shaft 9 is detected based on the pulse signal obtained by reaching the light receiver 8.

[0003]

[Problems to be solved by the device]

 Since the conventional hollow shaft encoder bearing structure is configured as described above, the following problems exist. That is, the oil scattered from each bearing may reach the rotary slit disk, which may disturb the slit pattern of the rotary slit disk, which may significantly impair the accuracy of the rotation detection signal.

The present invention has been made in order to solve the above problems, and in particular, by removing the oil splashing from the bearing with an oil cutout, the oil can be prevented from splashing to the rotary slit disk. It is an object of the present invention to provide a bearing structure for a hollow shaft encoder that is designed to prevent the above.

[0005]

[Means for Solving the Problems]

 A bearing structure for a hollow shaft encoder according to the present invention comprises a hollow rotary shaft rotatably mounted on first and second bearings provided on a base and a support separate from the base, and the first bearing. A first oil cutout located at one end of the second bearing, a second oil cutout located at one end of the second bearing, a rotary slit disk provided on the outer periphery of the hollow shaft, and the rotary slit circle. This is a configuration including a light-emitting body and a light-receiving body provided so as to face the plate.

[0006]

[Action]

 In the hollow shaft encoder bearing structure according to the present invention, since the oil cutouts are provided at one end side of each bearing, oil is prevented from splashing to the rotary slit disk at the position before each oil cutout, The state of the slit can always be kept good, and a stable rotation detection signal can be obtained.

[0007]

【Example】

 Hereinafter, preferred embodiments of a bearing structure for a hollow shaft encoder according to the present invention will be described in detail with reference to the drawings. It should be noted that the same or equivalent portions as those of the conventional example are designated by the same reference numerals and described. FIG. 1 is a sectional view showing a bearing structure for a hollow shaft encoder according to the present invention.

In the figure, reference numeral 1 is a base having a light emitting body 2, and a bearing hole 3 of the base 1 is provided with a first bearing 4. A support 6 is fixed above the base 1 via a support wall 5 provided on the base 1. The support 6 includes a first support 6a and a second support. It is composed of a part 6b. In addition, the respective support portions 6a and 6b can be integrated.

A second bearing 7 is provided on the inner wall 6aA of the first support portion 6a, and a light receiving body 8 is provided on the second supporting body portion 6b so as to correspond to the light emitting body 2. There is.

A pair of first and second oil drainers 11 and 12 having a ring-shaped overall shape are provided on the inner rings 4 a and 7 a of the bearings 4 and 7 via the first and second spacers 13 and 14, respectively. A hollow shaft 9 is provided rotatably, and the hollow shaft 9 penetrates through the guide hole 1a of the base 1 and the guide hole 6A of the first support portion 6A and projects outward.

The first oil drainer 11 is located on one end side 4A of the first bearing 4 and is located in the vicinity thereof. The second oil cutout 12 is located on the one end side 7A of the second bearing 7 and close to it.

A rotary slit disk 10 having a slit (not shown) of a predetermined pattern is attached at the central position of the hollow shaft 9, that is, between the bearings 4 and 7. The rotation state of the hollow shaft 9 is detected based on the pulse signal obtained by rotating the light beam from the light receiving body 8 to reach the light receiving body 8 through the slit of the rotating slit disk 10. There is.

[0013]

[Effect of the device]

 Since the bearing structure for the hollow shaft encoder according to the present invention is configured as described above, the following effects can be obtained. In other words, the oil splashing from the bearing is detected by the oil cutout body, so the slits of the rotary slit disc are always kept in a normal state without contamination, and it is possible to obtain a rotation detection signal with a stable difference value. it can.

[Brief description of drawings]

FIG. 1 is a sectional view showing a bearing structure for a hollow shaft encoder according to the present invention.

FIG. 2 is a sectional view showing a conventional configuration.

[Explanation of symbols]

 1 Base 2 Light emitter 4 First bearing 4A One end side 7 Second bearing 7A One end side 8 Photoreceptor 9 Hollow shaft 10 Rotating slit disk 11 First oil cutout 12 Second oil cutout 13 First spacer 14 Second Spacer

Claims (1)

[Claims for utility model registration] [Claim 1] The base (1) and the first and second bearings (4, 7) provided on the support (6) separate from the base (1) A hollow rotating shaft (9) rotatably provided and one end side (4) of the first bearing (4).
A first oil cutout body (11) located at (A), a second oil cutout body (12) located at one end side (7A) of the second bearing (7), and the hollow shaft (9)
A rotary slit disc (10) provided on the outer periphery of the rotary slit disc (10), and a light receiver (8) and a light emitter (2) provided to face the rotary slit disc (10), and A bearing structure for a hollow shaft encoder, wherein (11, 12) is provided on the hollow shaft (9).