JP2798814B2 - Switch housing and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch housing used for a push button switch and a method of manufacturing the same.
In particular, the present invention relates to a switch housing for preventing a fixed contact from being covered with a resin and a method of manufacturing the same.

[0002]

2. Description of the Related Art A conventional switch housing of this type will be described with reference to FIGS. FIG.
Is a cross-sectional view showing the entire structure of the push button switch, FIG. 6 is a cross-sectional view showing the relationship between the terminal and the housing after resin molding, and FIG. FIG. 8 is a cross-sectional view of a main part showing a manufacturing method of a second conventional example. FIG. 9 is a cross-sectional view of a main part showing a state of injection molding of a molten resin. FIG. 11 is a sectional view of a main part showing a manufacturing method of a third conventional example. The push button switch is made of a synthetic resin and has a housing 1 having an opening, and fixed contacts exposed on the inner bottom surface where the opening of the housing 1 is desired, for example, fixed contacts 2a, 2 on both sides.
b, a central fixed contact 2c, a cup-shaped movable contact 3 placed on both side fixed contacts 2a, 2b and facing the central fixed contact 2c, and provided on the movable contact 3 to fix the movable contact 3 A stem 5 for pressing the contact 5 toward the contact 2c; a frame movably supporting the stem 5 and attached to the upper end of the housing 1 by means such as caulking to suppress the upward movement of the stem 5; 6. As shown in FIGS. 7 and 10, the hoop member 7 used for the housing 1 has support portions 8, 9 extending in the longitudinal direction, central fixed contacts 2a, 2b connected to the support portion 8, and the other end. And the center fixed contact 2c extending from the support portion 9, and connection pieces 8a and 8b are provided between the fixed contacts 2a and 2b on both sides and the center contact 2c and each support portion. Although not shown in FIG. 7, other parts having the same configuration are sequentially arranged at equal intervals along the supporting portions 8 and 9. When manufacturing such a housing 1, first, the hoop material 7 is connected to the housing 1 as shown in FIG.
The molten resin 16 is injected through a gate 15 into a cavity formed between the fixed mold 13 and the movable mold 14 of the mold apparatus 12. Along with this,
From the side of the support portion 9 of the central fixed contact 2c, both-side fixed contacts 2a,
The cavity is filled with the molten resin 16 by flowing the molten resin 16 toward the support portion 8 side of the mold 2b, and then, after the molten resin 16 is cured, the mold is released from the mold device 18 to obtain the state shown in FIG. After the housing 1 is obtained, the support portions 8 and 9 projecting from both side ends of the housing 1 are cut off.

[0003]

Incidentally, in the above-mentioned prior art, the molten resin 16 injected from the gate 15 is not provided.
When passing through the vicinity of the support portion 9 of the central contact 2c, a force in the direction indicated by the arrow 17 in FIG. 9 acts on the support portion 9 and the bent portion 9b, so that these support portion 9, bent portion 9b, and The center fixed contact 2c is deformed from the state shown by the two-dot chain line to the state shown by the solid line. As a result, the resin flow path between the support part 9 and the movable mold 14 is widened, and the flow in this part is increased. There is a problem that a part of the molten resin 16 covers the contact surfaces of the fixed contacts 2a, 2b, 2c. When resin covering occurs on the contact surfaces 2a, 2b, and 2c in this manner, there is a concern that a contact failure of the contacts may be caused.

[0004] Therefore, as shown in FIG.
a, 2b, and 2c are brought into contact with the bottom surface 14a of the movable mold 14, and in this state, the molten resin 16 is filled from the gate 15 into the cavity. But,
In this case, since the injection pressure of the resin is directly applied to the side surfaces of the fixed contacts 2a, 2b, 2c, each of the contact portions 2a, 2b, 2c is moved by the pressure, and the resin is covered on the contacts. As a result, there is a problem that the contact is molded in an inclined state. As a remedy, for example, as shown in FIG. 8, a protrusion 2d is provided on the upper surface of the fixed contacts 2a, 2b, 2c, and a concave portion 19 is provided on the movable mold side so as to face the protrusion 2d. The protrusion 2d is located in the recess 19, and the base 2e of the fixed contacts 2a, 2b, 2c is brought into contact with the movable mold so that the resin does not enter the contact protrusion 2d. doing.

However, in the above-mentioned conventional manufacturing method, the movable mold 1 is used to prevent the fixed contact from covering the resin.
The base 2e of the fixed contacts 2a, 2b, 2c
And the projections 2 of the fixed contacts 2a, 2b, 2c
d is brought into contact with the inner surface 19 a of the concave portion of the mold 14,
In this case, the height of the protrusion 2d of each of the fixed contacts 2a, 2b, 2c and the depth of the recess 19 must be the same. High dimensional accuracy is required at the time of mold production, and as a result, there is a problem that the cost as a switch increases. Further, in the above manufacturing method, the molten resin 16
When the resin is filled into the cavity, the resin pressure from the gate is directly applied to the side surfaces of the fixed contacts 2a, 2b, 2c, and the resin injection pressure causes the contact portions 2a, 2b, 2
In this case, although the resin is not covered on the protrusion 2d, the contact is inclined due to the resin covered. There is a problem that the function as a device is impaired. Accordingly, the present invention has been made in view of such a situation of the related art, and an object of the present invention is to provide a method of manufacturing a switch housing that can prevent resin covering of a fixed contact.

[0006]

SUMMARY OF THE INVENTION In order to solve the above technical problem, the present invention provides a switch housing having a housing having an opening and a plurality of fixed contacts exposed on a bottom surface inside the opening of the housing. Protrusions formed on the housing are provided around the sides of the plurality of fixed contacts, and stepped portions are provided on the inner bottom surface of the case located between the fixed contacts.

In the method for manufacturing a switch housing according to the present invention, the structure is such that the upper surface of the fixed contact is brought into contact with the mold, and a mold and a recess are provided around the side of the fixed contact. A projecting portion is projected between the contacts by a mold, and the cavity in the mold is filled with molten resin.
The housing is configured to be molded.

[0008]

Since the side of the fixed contact is surrounded by the mold, the fixed contact does not directly receive the resin pressure when the molten resin is filled. Therefore, the movement of the fixed contact can be prevented.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a switch housing manufacturing method according to an embodiment of the present invention. 1 to 4
FIG. 1 is a view for explaining one embodiment of a method for manufacturing a switch housing according to the present invention. FIG. 1 is a perspective view showing the switch housing, FIG. 2 is a cross-sectional view of a main part of FIG. FIG. 4 is a sectional view of a main part showing a state in which molten resin is filled.
FIG. 2 is a sectional view of a main part showing a mold structure. In the present invention, the fixed contacts 22a, 22b, 22
c is exposed, and a pair of support members 23 and 24 is extended from the side of the housing 21, and the extended portions are used as terminals. In the configuration. That is, each fixed contact 22
a, 22b, and 22c are formed around the projections 25, 26, and 27, and a step-down portion 40 is provided on the inner bottom surface of the case located between the projections 25, 26, and 27. I have. As shown in FIG. 3, a mold apparatus 20 for molding such a housing 21 includes a cavity 31 formed on a joint surface between a stationary mold 28 and a nest 30 located on the movable mold 29 side, and a runner 31. And a gate 34 for injecting the molten resin 33 fed into the cavity 31 through the mold 32. In the initial state in which the hood material 35 is supplied to the mold apparatus 20, each of the fixed contacts 22a, 22b,
Reference numeral 22c denotes a fixed contact 22 which is positioned so as to be in contact with the inner bottom surface 30a of the recess of the nest 30 provided on the movable mold side 29.
The recess 30c is formed by providing a slight gap between the side surfaces of the recesses a, 22b, and 22c and the recess inner surface 30b. Further, between the fixed contacts 22a and 22c, and
Between the fixed contacts 22b and 22c (not shown), a protrusion 30d made of a mold is projected.

In this embodiment, as shown in FIG. 1, since the fixed contacts 22a and 22b are formed in a substantially rectangular shape, the shapes of the projections 25 and 27 are necessarily rectangular. Since the fixed contact 22c is formed in a substantially ring shape, the recess 30c around the fixed contact 22c is also formed in a ring shape. In this embodiment, when manufacturing the housing 21, first, the hood material 35 is supplied to the mold apparatus 20 and the hood material 3 is supplied.
After the pilot pin 37 is inserted and positioned in the hole 36 of the connecting portion of No. 5, the hoop material 35 is sandwiched between the fixed mold 28 and the movable mold 29 and is fed through the runner 32 in this state. The molten resin 33 is injected from the gate 34 into the cavity 31. After the molten resin 33 is cured, the movable mold 29 is lowered, and
By projecting the housing 21 to which the component 9 adheres and pushing up with the pin 38, the supporting portions 23 and 24 projecting from both ends of the housing 21 are cut off at predetermined positions after being separated from the mold device 20. . Since the sides of the fixed contacts 22a, 22b and 22c are surrounded by the mold, the molten resin can be supplied directly from the gate to the fixed contacts 22a, 2c.
The resin does not flow between the upper surfaces of the inserts 2b and 22c and the insert 30, and the problem of the resin covering of the contact portion can be solved. Further, in the structure of the present invention, since the upper surface of the fixed contact is formed flat, the height dimension from the bottom surface of the case to the upper surface of the contact can be reduced. In the above embodiment, the protruding portions 25, 26, and 27 formed around the fixed contact portions 22a, 22b, and 22c are formed on the same surface as the respective contacts, but this is an example. It is also possible to provide a taper around the parts 25, 26, 27. Further, in the present embodiment, the structure in which the center fixed contact 22c is formed at a position lower than the both-side fixed contacts 22a and 22b is described. Can also be increased.

[0011]

As described above, the present invention is configured as described above, so that resin covering of the contact portion can be prevented without causing resin covering on the upper surface of the fixed contact. Therefore, a highly reliable contact structure can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a switch housing of the present invention.

FIG. 2 is a sectional view of a main part of a switch housing of the present invention.

FIG. 3 is a cross-sectional view of a main part showing a state in which a cavity of the mold device of the present invention is filled with a molten resin.

FIG. 4 is a sectional view of a main part showing a mold structure of the present invention.

FIG. 5 is a cross-sectional view showing the entire structure of a conventional push button switch.

FIG. 6 is a cross-sectional view of a main part showing a conventional relationship between a terminal and a housing.

FIG. 7 is a cross-sectional view of a main part showing a conventional relationship between a hoop material and a housing.

FIG. 8 is a cross-sectional view of a main part showing a manufacturing method of a second conventional example.

FIG. 9 is a cross-sectional view of a main part showing a conventional molten resin injection molding state.

FIG. 10 is a perspective view of a main part showing a conventional FOUP-shaped fixed contact.

FIG. 11 is a sectional view of a main part showing a third conventional state of injection molding of a molten resin.

[Explanation of symbols]

 21 Housing 22a, 22b, 22c Fixed contact 25, 26, 27 Projection 30 Mold 30b Depression 30c Projection 35 Hoop material 40 Step-down portion

Claims (2)

(57) [Claims] 1. A switch housing having an opening and a plurality of fixed contacts exposed on an inner bottom surface of the opening, wherein a projection formed on the housing is formed around a side of the plurality of fixed contacts. A switch housing, wherein a step-down portion is provided on the inner bottom surface of the case located between the fixed contacts. 2. A method of manufacturing a switch housing, comprising: supplying a hoop material having a plurality of fixed contacts to a mold device; and filling a cavity of the mold device with a molten resin to mold the switch housing. A structure in which the upper surface of the fixed contact is brought into contact with the mold, a recess is provided around the side of the fixed contact, and a projection is projected between the contacts by a mold, and the cavity in the mold is provided. A method for manufacturing a switch housing, characterized in that a housing is formed by filling a molten resin into the housing.