JPH0457111A - Knob fitting structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a rotary knob mounted on an operating surface of a television, video, audio equipment, office automation equipment, etc.

[Conventional technology]

Conventional techniques are shown in FIGS. 7, 8, and 9.

In FIG. 7, the shaft 16 for moving the variable resistor is composed of a cylindrical portion 16a and a portion 16b obtained by cutting the cylindrical column in the axial direction. The cross-sectional area of 16b perpendicular to the axis is larger than a semicircle. FIG. 8 shows a plastic-molded knob attached to 16, which is composed of an operating section 18 and a bearing section 19. The bearing portion 19 has a shape that allows it to be tightly fitted to each of 16a and 16b, and the knob is connected to the shaft 1.
When inserted into 6, the boss 20 inside 19 comes into contact with the upper surface 17 of 16, and the mounting position of the knob is determined. 1
9 is provided with a notch 21 in the axial direction. FIG. 9 is a sectional view of 19 attached to 16. , 19 are slightly smaller than the external dimensions of 16a and 16b, so 19 can open 16 by opening the notch 21.
It becomes possible to insert into. At this time, the opening 19 does not open at the base of the operating section 18, and the opening dimension increases toward the tip. Therefore, the tip 22 of 16 touches the inside of 19,
At other locations, gaps are created between the insides of 16 and 19.

This gap may not be uniform on the left and right sides, and FIG. 9 shows a case where the gap 24 on the right side is the maximum /JX and the gap 23 on the left side is the maximum. At this time, the axial center of 19 is 1G
does not coincide with the axial center of the knob, resulting in eccentricity of the operating portion 18, which deteriorates the appearance when operating the knob. Eccentricity of the knob occurs when the gaps 24 and 23 are not uniform.

19 is fixed to 16 by tightening 16 because the elasticity of the plastic exerts a force to return it to its original state.

In addition, as a product of this kind, Utility Model No. 53-79346
There are publications etc.

[Problem to be solved by the invention]

- The prior art mentioned above does not take into account the fact that when the knob is attached to the shaft of the variable resistor, the center of the bearing 19 must be aligned with the center of the shaft 16, and the operating section 1
There was a problem in that when the 8 was rotated, it became eccentric and the appearance deteriorated.

An object of the present invention is to provide a structure that allows a knob to be attached to the shaft of a variable resistor without eccentricity.

[Means to solve the problem]

In order to achieve the above purpose, a hole is provided in the center of the shaft of the variable resistor, and a boss is provided in the center of the bearing of the knob. It is designed to fit tightly together with a loose fit.

[Effect]

When attaching the knob to the shaft, the boss at the center of the knob bearing is fitted into the hole at the center of the shaft with a loose fit.

Thereby, the knob can be mounted on the shaft without eccentricity.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1, 2, 3, 4, 5, and 6.

In Figure 1, the axis 1 of the variable resistor is the axis 1 of the cylindrical part.
a, and a shaft 11 which is a portion of a cylinder cut in the axial direction. ■The cross-sectional area of b, cut perpendicular to the axis, is larger than a semicircle. The top surface 4 of 1a is flat, and the knob 5 is
- When attached to the position, it plays a role in determining the depth of push-in of the knob. A hole 2 is provided in the center of 1b in the axial direction, and the entrance of the hole is chamfered 3. The opening of hole 2 is smaller than the diameter of the hole. That is, the circumference of the hole 2 is larger than 180°. The knob 5 is a plastic molded product and is inserted into the shaft 1 in the direction of the arrow.

FIG. 4 is an enlarged view of the axis 1.

Figure 2 is a sectional view taken along line A-A in Figure 1, and Figure 3 is a cross-sectional view taken along line B-- in Figure 2.
B shows a sectional view.

In FIGS. 2 and 3, the bearing portion 6 of the knob has a chamfer 7 at its tip to facilitate insertion into the shaft 1. axis 1b
The boss 8 is fitted into the notched part. When the knob is inserted into position 1, the lower surface 9 of the boss 8 abuts against the -L surface 4 of the shaft 1a, and the position of the knob is determined. The boss 8 is formed with a boss 10 that fits into the hole 2 of the shaft 1b with a clearance, and the lower surface of the boss 10 is chamfered 11 to make it easier to fit into the hole 2. Since the inner dimension of the bearing part 6 is slightly smaller than the outer dimension of the shaft 1, when the bearing part 6 is inserted into the shaft 1, the inner dimension of the bearing part 6 must become larger toward the outside. For this purpose, a notch 12 is provided in the bearing portion 6 on the side opposite to the boss 8.

FIG. 5 shows a state in which the knob 5 is attached to the shaft 1. The bearing portion 6 becomes wider from the root to the tip. The notch 12 in the bearing part opens, but due to its elasticity there is always a force that tries to return it to its original state, and this force causes the shaft to open.
, so that the bearing portion 6 is fixed to the shaft 1.

FIG. 6 shows a cross-sectional view of FIG. The boss 10 of the knob 5 is fitted into the hole 2 of the shaft with a loose fit.

When the knob 5 is pushed all the way in, the tip 13 of the shaft 1 comes into contact with the inner surface of the bearing 6, and the tip of the bearing 6 opens outward. Therefore, a gap 14 and a gap 15 are generated between 6 and 1, but the dimensions of 14 and 15 are equal. That is, the knob 5 is mounted without being eccentric with respect to the shaft 1.

〔Effect of the invention〕

According to the present invention, since the eccentricity of the knob is eliminated when the knob is operated, the appearance is improved and the operability is improved.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention, and FIG. 2 is a perspective view showing one embodiment of the present invention.
Figure 3 is a sectional view taken along line A-A in the figure, Figure 3 is a BB cross-sectional view in Figure 2, and Figure 4 is
The figure is a top view of the shaft in Figure 1, Figure 5 is a front view of the knob attached to the shaft in Figure 1, Figure 6 is a sectional view of Figure 5, and Figure 7 is the shaft of a conventional variable resistor. 8 is a perspective view of a conventional knob, and FIG. 9 is a sectional view of the knob attached to the shaft of FIG. 7. 1...shaft, 1a...shaft, 1b...shaft, 2...hole,
3... Chamfer, 5... Knob, 6... Bearing part, 8
...Boss, 10...Boss, 11...Chamfer, 12
...Notch, 14...Gap, 15...Gap.

Claims (1)

[Claims] 1. In the knob mounting structure consisting of a shaft that drives a rotary variable resistor and a knob that engages with this shaft, the shaft is a cylinder with a certain length from the base to the tip, and the length from the middle to the tip is a cylinder. It is shaped like a cylinder cut in the axial direction, with a hole in the center of the shaft running from the tip to the base, the knob is a plastic molded product, and a bearing part that engages with the shaft is provided, and the bearing part is inserted in the longitudinal direction of the shaft. It has a notch in one place that fits into the outer shape of the shaft, and a boss that fits into the hole in the center of the shaft, and the boss fits into the hole in the shaft when the knob is installed. A knob mounting structure characterized in that the shaft and the knob have the above-described shape, thereby preventing eccentricity of the knob and generating a removal force by engaging the bearing part of the knob with the outer shape of the shaft.