JPH0517768Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a selector switch which can select a switch circuit by rotating the operating knob, which rotates in unison with the operating knob. This invention relates to a sealing structure between a dynamic operation shaft and a main body housing that houses the shaft.

<Prior Art> A conventional seal structure for this type of selector switch generally has a configuration as shown in FIG. 3 or 4. That is, the selector switch shown in FIG.
is slidably displaced within the main body housing 4, and the operating shaft 3 is configured to open and close a contact section (not shown) attached to the lower part. The seal structure between the main body housing 4 and the operating shaft 3 in this selector switch is such that the upper end portion of the rubber bellows 5 is pressed against the horizontal surface of the operating shaft 3 by a coil spring 6, and the lower end portion of the rubber bellows 5 is pressed against the horizontal surface of the operating shaft 3. to press the rubber bellows 6 against the main body housing 4.
This structure provides a sealing effect between the two.

On the other hand, in the selector switch shown in FIG. 4, the operating shaft 8 itself is rotated by an operating knob (not shown), and the contact portion is moved by an operating cam (not shown) provided at the lower end of the operating shaft 8. (not shown). The seal structure between the main housing 9 and the operating shaft 8 in this selector switch is such that the operating shaft 8 and the main housing 9
Between the facing surfaces of the ring-shaped D packing 1
0 is fitted into a groove 11 formed on the outer peripheral surface of the operating shaft 8, and is brought into sliding contact with the inner peripheral surface of the main body housing 9 when the operating shaft 8 rotates.

<Problems to be solved by the invention> However, the seal structure shown in FIG. 5 is pressed against the operating shaft 3, the operating shaft 3 itself cannot be a rotating body, and the operating shaft 3 is slidably displaced within the main body housing 4 by the operating cam 2.The selector switch has a complicated structure. As a result, costs are increasing. In addition, since the rubber bellows 5 is configured to obtain a sealing effect on the circumferential surface, the sealing effect varies, and furthermore, the sealing effect between the rubber bellows 5 and the main body housing 4 also depends on the tightness of the bottom cover 7. It shifts and varies. Moreover,
In order to ensure the sealing effect between the rubber bellows 5 and the main body housing 4, care must be taken not to deform the rubber bellows 5 when assembling the bottom cover 7, which may result in various problems such as poor assembly. There are drawbacks.

On the other hand, the one shown in Fig. 4 has the advantage of providing a selector switch with a simplified structure in which the operation shaft 8 itself is a rotating body compared to the one shown in Fig. 3, but it is waterproof,
Since the structure is configured to obtain a sealing effect with a single D seal 10 for oil and dust protection, a sufficient sealing effect and smooth rotation of the operating shaft 8 so as to provide a feeling of light load operation are achieved. To obtain the operation axis 8,
There is a problem in that extremely high precision is required in the dimensions of the mutually fitting portions of the D packing 10 and the main body housing 9.

The present invention was devised in view of these conventional technical problems, and it is possible to construct a selector switch at low cost by using the operating shaft itself as a rotating body, and it also provides a uniform sealing effect, and is easy to assemble. The purpose of this invention is to provide a seal structure for a selector switch that does not require high precision.

<Means for Solving the Problems> The present invention has the following technical means for achieving the above-mentioned objects. In other words, waterproof, oil-proof,
A seal structure for dustproofing includes a rubber bellows having a sealing part projecting inwardly from one end in the shape of a brim and a locking part having a hook-shaped cross section projecting outward from a part near the other end. A rubber bellows is press-fitted into the main body housing, the locking part is engaged with the engaging part of the main body housing, and the seal part is pressed into contact with the outer circumferential surface of the rotating operation shaft. .

Further, a circumferential groove is provided on the surface facing the main body housing at a lower position with respect to the seal portion of the rubber bellows on the rotation operation shaft, and a ring-shaped gasket fitted in the circumferential groove is attached to the main body housing. A structure for sliding contact can also be added.

<Function> The inner flange-shaped seal portion of the rubber bellows comes into pressure contact with the outer peripheral surface of the rotating operation shaft due to its own rubber elasticity, and a sealing effect is obtained between the rubber bellows and the rotating operation shaft. The locking part of the rubber bellows engages with the engaging part of the main body housing to obtain a sealing effect between the rubber bellows and the main body housing, and sealing is performed between the rotating operation shaft and the main body housing via the rubber bellows. be exposed. In this way, since the rubber elasticity of the rubber bellows is used to obtain a sealing effect at the contact portion with the operating shaft, there is no need for a coil spring or the like, and the operating shaft itself can be used as a rotating body. Since the rubber elasticity of this rubber bellows has a degree of freedom, smooth rotation of the operating shaft can be obtained. Furthermore, unlike surface contact based on the pressure of a coil spring, rubber elasticity with a large degree of freedom is utilized, so there is almost no variation in the sealing effect. Furthermore, the rubber bellows can be incorporated as a sealing member by a simple method of press-fitting the locking portion of the rubber bellows into the main body housing and locking it to the engaging portion thereof.
Moreover, by using the rubber bellows, mutual dimensional accuracy between the main body housing and the rotating operation shaft is not required.

In addition to the rubber bellows, if a seal is provided between the rotation operation shaft and the main body housing by a gasket fitted onto the rotation operation shaft, a double sealing effect can be obtained. In other words, the seal part of the rubber bellows functions as waterproof, oil-proof, and dust-proof, but even if for some reason water or oil passes between this seal part and the rotating operation shaft, it will not damage the gasket below it. Thus, a reliable sealing effect can be obtained.

<Example> Hereinafter, preferred examples of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a longitudinal section of an embodiment of the present invention, with planes cut at different angles on both sides of the center line. In the same figure, a rotation operation shaft 14 having a rotation operation knob 13 integrally fitted to one end is rotatably housed in the main body housing 12, and the rotation operation shaft 14 is attached to the other end of the rotation operation shaft 14. An operation cam (not shown) is attached, and the operation of this operation cam operates the pusher 15 in the vertical direction in the figure. A contact portion (not shown) fixed by screwing into the contact portion 16 is opened and closed. Further, a mounting base 17 is fixed to the main body housing 12 by caulking means, a plurality of waterproof gaskets 18 are fitted onto the mounting base 17, and a mounting ring 19 is screwed onto the mounting base 17. When installing this selector switch, the selector switch is fixed to the panel by positioning the panel between the waterproof packing 18 and the mounting ring 19 and tightening the mounting ring 19.

Next, to explain the sealing structure which is the gist of the present invention, the rubber bellows 20 as a sealing member
As shown in FIG. 2, which is an enlarged view of this, an inner flange-shaped seal portion 20a is provided at one end, which is the upper part of the figure, to protrude inwardly, and the other end part, which is the lower part of the figure, has a circumferential surface. To,
A locking portion 20b having a hook-shaped cross section is provided to protrude outward. The seal portion 20a is formed to have an inner diameter slightly smaller than the outer diameter of the sealing surface 14a of the rotating operating shaft 14, which is indicated by a two-dot chain line in FIG. At this time, the diameter is slightly expanded outward as shown by the dashed line, and its restoring force presses against the sealing surface 14a. In addition, the locking portion 2 of the rubber bellows 20 is placed at a proper location on the main body housing 12.
A step-like engaging portion 12a is formed with which the locking portion 20b engages, and by press-fitting the rubber bellows 20 in the direction of the arrow in FIG.
The rubber bellows 20 is fixed by engaging the portion a.

Further, similar to the existing one shown in FIG. 4, a circumferential groove 14b is provided on the surface of the rotating operation shaft 14 facing the main body housing 12 at a position below the seal portion 20a of the rubber bellows 20, and this circumferential groove 14b In some cases, a ring-shaped D-packet 21 is fitted into the main body housing 12 so that the D-packet 21 is brought into sliding contact with the main body housing 12.

When assembling the selector switch, when assembling the rubber bellows 20, press the rubber bellows 20 in the direction of the arrow in FIG.
By sufficiently pushing the bellows 20 until it passes through the engaging portion 12a, the locking portion 20b is slightly bent and then engages with the engaging portion 12a by restoring force, thereby fixing the rubber bellows 20 to the main body housing 12. , the rubber bellows 20 and the main body housing 12 are reliably sealed. At this time, the seal portion 2 of the rubber bellows 20
0a is slightly enlarged in diameter as shown by the two-dot chain line in FIG. A seal is made with 14. That is, a seal is established between the rotating operation shaft 14 and the main body housing 12 via the rubber bellows 20. In this way, since the contact portion with the rotating operation shaft 14 is sealed only by the rubber elasticity of the rubber bellows 20, the operating shaft 14 itself can be used as a rotating body, and since the rubber elasticity has a degree of freedom, the rotating operation can be performed. The shaft 14 rotates extremely smoothly,
Moreover, there is almost no variation in the sealing effect.

In addition to the rubber bellows 20, a rotating operation shaft 14 is also provided.
Fit the D packing 21 into the circumferential groove 14b of the D
If a sealing effect is obtained between the rotary operation shaft 14 and the main body housing 12 by the seal 21, a double sealing effect will be provided for waterproofing, oilproofing, and dustproofing, making it even safer. Become. That is,
If water or oil were to leak between the seal portion 20a of the rubber bellows 20 and the seal surface 14 of the rotation operation shaft 14 for some reason,
Even if it passes through the space between A and A, the D packing 21 prevents it from entering the inside.

<Effects of the invention> As detailed above, the sealing effect of the selector switch of the invention is such that the seal portion protrudes inward from one end in the shape of a brim and the cross section protrudes outward from the vicinity of the other end. A rubber bellows having a hook-shaped locking portion is press-fitted into the main body housing, the locking portion is locked to the engaging portion of the main body housing, and the seal portion is pressed against the outer circumferential surface of the rotation operation shaft. With this structure, the rubber elasticity of the rubber bellows can seal the contact area between the rubber bellows and the operating shaft, so the operating shaft itself can be a rotating body, and a sealing effect can be obtained through surface contact. Therefore, a coil spring or the like is not required, and a simple and inexpensive selector switch can be constructed.

Furthermore, since the rubber elasticity of the rubber bellows in the seal portion has a degree of freedom, the rotation operation shaft can be rotated smoothly, and the rubber bellows and the main body housing are fixed by an engaging means. , it is possible to obtain a uniform sealing effect and high reliability. Moreover, since the rubber bellows can be assembled simply by press-fitting, assembly efficiency is improved. Furthermore,
Since the rotary operation shaft and the main body housing are sealed via the rubber bellows, high precision is not required in the dimensions between them.

Moreover, by fitting a gasket at a position below the rubber bellows on the operating shaft, a double and safer sealing effect can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of a selector switch to which a seal structure of an embodiment of the present invention is applied, Fig. 2 is a partially cutaway enlarged view of the rubber bellows in Fig. 1, and Figs. 3 and 4 are respectively conventional FIG. 2 is a partially cutaway front view and a partially vertical cross-sectional view of a selector switch having a seal structure. 12...main housing, 12a...engaging portion,
14... Rotating operation shaft, 14b... Circumferential groove, 20...
Rubber bellows, 20a... Seal part, 20b...
Locking part, 21...Packkin.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In the seal structure for waterproofing, oilproofing, and dustproofing between the main body housing of the selector switch and the rotary operation shaft rotatably installed inside the selector switch, one end a rubber bellows having a sealing part projecting inwardly from one end in the shape of a flange, and a locking part having a hook-shaped cross section projecting outward from a part near the other end; the rubber bellows is press-fitted into the main body housing; A seal structure for a selector switch, characterized in that the locking portion is engaged with the engaging portion of the main body housing, and the sealing portion is pressed against the outer peripheral surface of the rotation operation shaft. (2) A circumferential groove is provided on the surface facing the main body housing at a lower position with respect to the seal portion of the rubber bellows on the rotation operation shaft, and a ring-shaped gasket fitted in the circumferential groove is attached to the main body housing. 2. The seal structure of a selector switch according to claim 1, wherein the seal structure is in sliding contact with the selector switch.