JPH0132263Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a push button structure of a push button switch.

A typical example of a conventional pushbutton switch and button structure of this type is shown in FIG. 1 is a button, 2 is a cover that accommodates the button 1 and supports the switch components;
3 is a rubber molded product, 3-1 is a convex elastic part as a spring for restoring the button 1, 3-2 is an actuator part,
3-3 is a contact electrode pair 4-1 provided on the printed board 4
This is an electrically conductive member that is bridged by pressing the button 1. Button 1 is display symbol 1-1 and body 1
-2 and a second molded body filling the display surface 1-3 in a color different from that of the first molded body. In the primary molded body, the display symbol 1-1 is, for example, the number "4""6""8""9""0"
In such a case, a passage for passing the resin is required inside the area surrounded by the display symbol 1-1 when forming the secondary molded body. Furthermore, since the main body 1-2 has a thick wall, it is necessary to cut out the thickness to prevent so-called "sink".

The structure for creating such a passage through which the resin passes will be explained with reference to FIG. The numerical example of the display symbol 1-1 is "0", and Figure 2 a-1 and Figure 2 b-1 are perspective views as seen from the display symbol 1-1, Figure 2 a-2 and Figure 2
Figure b-2 is - of Figure 2 a-1 and Figure 2 b-1.
FIG. In A, the passage structure is a-1,
At a-2, display symbol 1 in the direction of mold removal.
Hole 1- which takes into account the flow of the resin and the relationship with the operator part 3-2 of the rubber molded product 3, so that the upper end opens on the inside and outside surrounded by the display symbol 1-1 at the position intersecting with the symbol 1-1. 4 is provided, and this is the passage 1-4a.
It also serves as the meat cutter 1-4b. Further, in B, the passage 1-5 is formed by a sliding piece (not shown in the mold) perpendicular to the cutting direction of the mold, and the lightening 1-6 is provided in the same manner as in the structure of A. For this reason, in structure A, when forming the secondary molded body, the core pin of hole 1-4 (not shown in the mold) moves by h shown in Figure 2 a-2 to create a passage. , end 1
-4c cannot be rounded and becomes a sharp edge. Therefore, when the button operation force is large, the rubber molded product 3 becomes flexible and the actuator portion 3-2 is compressed as shown in FIG.
-4c bites into the first portion 3-2a of the actuator portion 3-2, resulting in breakage of the surface of the actuator portion 3-2, which may impede the switch characteristics. In addition, in the structure B, the problem with the rubber molded product 3 is solved because the end 1-6a of the hollowed out part 1-6 is rounded, but the passage 1-5 has a mold that is attached to the sliding piece. As a result, the mold becomes complicated, there is a limit to the efficiency of material removal, and the cost increases.

In order to solve these drawbacks, the present invention provides a push button structure for a push button switch in which the hollow hole of Structure A is filled in at the same time as the surface part is formed during secondary molding. It is something.

The present invention will be explained in detail below.

FIG. 4 shows an embodiment of the push button according to the present invention, in which a is a primary molded body for forming a display symbol 11-1 and a main body 11-2, and is a cross section taken along line XX shown in FIG. Passage 1 of the display symbol 11-1 is provided in the passage and hollow hole 11-4 including the hollowed-out portion 11-4b provided in the same direction as the axial direction of the main body 11-2.
1-4a-1, filling passage 1 of hollowed out part 11-4b
1-4a-2 is provided. b is the cross section of the push button after the second molding, and during the second molding, the core pin (not shown in the mold) of the hole 11-4 during the first molding is at the depth of the hole 11-4. The molding machine is driven so that the hole 11-4 is closed at a position that matches the contact surface 11-6 of the rubber molded product 3 with the effector part 3-2 (see Fig. 1). , are located above and below the display surface 11-3 and the hollowed out portion, respectively. Aisle 11-4
Resin flows from a-1 and passage 11-4a-2, and fills filling portion 11-5 (hole 11-4). The filling passage of this filling part 11-5 is the hollow part 1
Since the filling is performed from both sides of the display symbol 1-4b, the resin pressure to the display symbol 11-1 can be set in the same way as before, and the display part 1
There are no problems such as deformation or fogging as described in 1-1. In addition, since there is no hole in the contact surface 11-6 of the rubber molded product 3 that comes into contact with the effector part 3-2 (see Fig. 1), there is no partial compression of the effector part 3-2, and the effector part 3-2 has been resolved, and the size of the hole 11-4 has also been changed to the effector part 3.
There is no need to consider the relationship with -2, and the dimensions seen from the button molding can be determined as shown by the two-dot chain line in FIG.

As explained in detail above, according to the push button structure according to the present invention, resin is filled inside and outside of the display symbol 11-1 through the hole 11-4 above the hollowed out part.
Since the filling is carried out from both a-1 and the lower hole 11-4a-2, the air in the space can escape from either one, and sufficient filling pressure can be obtained, so the second molded body can be placed sufficiently on the display surface. It is possible to fill it.

Moreover, since the hollowed out part is filled with the second molded body, there is no increase in the cost of the button, and the edge existing at the lower end of the hollowed out hole allows the rubber to be Since there is no risk of damaging the actuating element, the effect of stabilizing the operation of a push button switch used in combination with this push button can be obtained.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a conventional pushbutton switch and button structure, Fig. 2 is a perspective view and sectional view showing the main parts of the conventional button structure, and Fig. 3 is for explaining the drawbacks of the conventional button structure. A cross-sectional view of
FIG. 4 is a sectional view showing an embodiment of the present invention. 1...Button, 1-1...Display symbol, 1-
2...Body, 1-3...Display surface, 1-4...Hole,
1-4a...Aisle, 1-4b...Meatless, 1-4
c... End, 1-5... Passage, 1-6... Lightening, 1-6a... End, 2... Cover, 3... Rubber molded product, 3-1... Convex elastic part , 3-2...Action element part, 3-3...Conductive member, 4...Printed board,
4-1...Contact electrode pair, 11-1...Display symbol, 11-2...Main body, 11-3...Display surface, 1
1-4...Aisle and cutout hole, 11-4a-1...
Passage, 11-4a-2...Filling passage, 11-4b
... Lightening part, 11-5 ... Filling part, 11-6...
...Abutting surface.

Claims (1)

[Scope of utility model registration request] a first molded body integrally formed with a button body and a display symbol projected on its display surface; A lightening part is provided in the first molding body in the same direction as the axial direction of the button body, and the lightening part is for resin filling when molding the second molded body. Both ends of the passage are formed so as to open in the display surface and the lower end of the hollowed out part, respectively, and the hollowed out part and the resin filling passage when molding the second molded body and the first molded body are filled with resin. A push button structure for a push button switch, characterized in that a hole for hollowing out the body is filled with the second molded body.