JPH0543022U - Mounting structure of sensor part in optical encoder - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a mounting structure for a sensor part that is excellent in temperature characteristics and that can prevent positional displacement as much as possible in a mounting structure for a sensor part that is clamped and fixed to an optical encoder. .. [Structure] A one-point tightening structure for fixing the sensor unit 16 on the base 11 using one tightening screw 19 is adopted, and a washer fixing screw 18 is mounted on the sensor unit 16.
By installing the position-displacement regulating washer 17 therewith, it is possible to prevent the position displacement due to the tightening torque when tightening the screw.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a mounting structure of a sensor unit in an optical encoder, and more particularly to a mounting structure of a sensor unit in an optical encoder which has excellent temperature characteristics, has little positional deviation, and has high reliability.

[0002]

[Prior Art]

 Usually, in an optical encoder, as shown in FIG. 3, a bearing unit 2 having a scale glass is rotatably attached to a central portion of a base 1 so that the scale glass 3 is sandwiched from above and below. A sensor unit 6 including a light emitting element 4, a light receiving element 5 and the like is mounted on the base 1.

As shown in FIG. 4, the mounting structure of the sensor unit 6 is a two-point tightening structure in which two tightening screws 7 are screwed in via a washer 8 to mount the sensor unit 6. As shown in, there is a one-point tightening structure in which a single tightening screw 7 is fixed via a washer 8.

[0004]

[Problems to be solved by the device]

 However, in such a conventional mounting structure of the sensor section 6, for example, in the case of the two-point tightening structure shown in FIG. It has been pointed out that there is a large variation in temperature characteristics due to the delicate balance of.

Further, in the case of the one-point tightening structure shown in FIG. 5, it is pointed out that when the tightening screw 7 is tightened, displacement is likely to occur and the sensor part 6 cannot be set in a precise position. Has been done.

The present invention has been made in view of such circumstances, and an object of the present invention is to reduce the influence of thermal expansion and thermal contraction, to reduce variations in temperature characteristics, and to reduce tightening torque. Another object of the present invention is to provide a mounting structure for a sensor unit in an optical encoder that prevents positional displacement as much as possible.

[0007]

[Means for solving the problem]

 In order to achieve the above object, the present invention relates to a mounting structure of a sensor part in an optical encoder for fixing a sensor part on a base supporting a bearing unit equipped with a scale glass via a tightening screw. It is characterized in that a washer for positional deviation regulation that is inserted into a screw to reduce the tightening torque is fixed on the sensor part with a washer fixing screw.

[0008]

[Action]

 As is clear from the above configuration, since the sensor is fixed on the base by one tightening screw, the temperature characteristics are the same as the one-point tightening structure, and the fulcrum of thermal expansion and contraction, etc. A stable temperature characteristic with 1 point is obtained.

Furthermore, since the tightening torque of the tightening screw is relaxed by the washer that is fixed on the base by the washer fixing screw, there is only one position deviation when the tightening screw is tightened. It is less than half of the tightening structure and comparable to the level of a two-point tightening structure.

[0010]

【Example】

 Hereinafter, embodiments of a mounting structure of a sensor unit in an optical encoder of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a plan view showing a structure of an optical encoder to which a sensor part mounting structure according to the present invention is applied, and FIG. 2 is a sectional view showing a sensor part mounting structure according to the present invention.

In FIG. 1, an optical encoder 10 according to the present invention has a bearing unit 12 rotatably attached to a base 11, and a scale glass 13 attached to the bearing unit 12 is sandwiched from above and below. The sensor portion 16 provided with the light emitting element 14 and the light receiving element 15 is mounted on the base 11.

By the way, the feature of the present invention resides in the mounting structure of the sensor part 16 for mounting the sensor part 16 on the base 11.

That is, as shown in FIG. 2, a displacement-regulating washer 17 for regulating the displacement of the sensor portion 16 is fixed to the sensor 16 via a washer fixing screw 18, and the sensor portion 16 is fixed. The tightening screw 19 for fixing the base plate 11 on the base 11 is provided through the position displacement regulating washer 17 and the flat washer 20. Reference numeral 21 in the figure indicates a sleeve.

As described above, the mounting structure of the sensor unit 16 according to the present invention is a one-point tightening structure because it is performed by the tightening screw 19, and the fulcrum at the time of thermal expansion and thermal contraction is one point. It exhibits stable temperature characteristics.

Further, regarding the positional deviation, which is a defect of the one-point tightening structure, by installing the washer 17 for restricting the positional deviation, it is possible to prevent the positional deviation to a level comparable to that of the two-point tightening structure. It will be possible.

As described above, the mounting structure of the sensor unit 16 according to the present invention is configured to have the advantages of the one-point tightening structure and the two-point tightening structure, thereby promoting the high accuracy of the optical encoder 10. it can.

[0018]

[Effect of the device]

 As described above, the mounting structure of the sensor part in the optical encoder according to the present invention adopts the one-point tightening structure in which the sensor part is fixed on the base with one tightening screw, so that stable temperature characteristics can be obtained. In addition, the misalignment at the time of tightening the torque is eliminated by installing a washer for restricting the misalignment, and the misalignment due to the torque at the time of tightening the screw is prevented as much as possible. It has the effect that it can greatly contribute to commercialization.

[Brief description of drawings]

FIG. 1 is a plan view showing a schematic configuration of an optical encoder to which the present invention is applied.

FIG. 2 is a sectional view showing an embodiment of a mounting structure of a sensor unit according to the present invention.

FIG. 3 is a sectional view showing a schematic configuration of a conventional optical encoder.

FIG. 4 is a cross-sectional view showing a conventional mounting structure of a sensor unit in an optical encoder.

FIG. 5 is a cross-sectional view showing a conventional mounting structure of a sensor unit in an optical encoder.

[Explanation of symbols]

 10 Optical Encoder 11 Base 16 Sensor Part 17 Positional Control Washer 18 Washer Fixing Screw 19 Tightening Screw 20 Flat Washer 21 Sleeve

Claims (1)

[Scope of utility model registration request] 1. A mounting structure of a sensor section in an optical encoder, wherein a sensor section is fixed on a base supporting a bearing unit including a scale glass via a tightening screw, and the tightening torque is inserted by inserting the sensor into the tightening screw. The mounting structure of the sensor unit in the optical encoder, in which the position deviation washer to be relaxed is fixed on the sensor unit via the washer fixing screw.