JP2721425B2 - Switch wafer and manufacturing method thereof - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a switch wafer used for a push button switch and a method of manufacturing the same, and more particularly, to a switch wafer suitable for preventing fixed contacts from being covered with resin. It relates to the manufacturing method.

[Conventional technology]

7 to 10 are views for explaining a conventional example of a method of manufacturing a switch wafer. FIG. 7 is a cross-sectional view showing a configuration of a push button switch provided with the switch wafer. FIG. 8 is a plan view of a hoop material. FIG. 9 is a plan view showing the state of the wafer after molding, and FIG. 10 is a cross-sectional view showing a state in which the cavity of the mold apparatus is filled with molten resin. FIG. 7 is a diagram corresponding to FIG.
FIG. 10 is a sectional view taken along line BB of FIG. 9;

The push button switch shown in FIG. 7 is made of synthetic resin and has an opening 1 and fixed contacts such as common contacts 2a, 2b, which are exposed on the inner bottom surface of the wafer 1 where the opening is desired.
And the center contact 2c and the common contacts 2a, 2b,
A cup-shaped movable contact 3 facing the central contact 2c, a sheet 4 provided on the movable contact 3 and closing the opening,
A stem 5 for pressing the movable contact 3 toward the fixed contact 2c via the sheet 4 and a frame 6 and the like which movably support the stem 5 and are fastened to the wafer 1 are provided.

As shown in FIG. 8, the hoop material 7 used for the above-described wafer 1 is connected to support portions 8 and 9 extending in the longitudinal direction and one of the support portions 8 via bent portions 10 and 11, respectively. The common contacts 2a, 2b and the other supporting portion 9 have bent portions.
It has the central contact 2c connected via 12 and a connecting portion 14 formed with a hole 13 and connecting the supporting portions 8 and 9 to each other. In addition, a pilot pin 32 of FIG. 2 described later is inserted into the hole 13. Also, the eighth
Although not shown in the drawing, other parts configured in the same manner are sequentially arranged at equal intervals along the supporting portions 8 and 9.

When manufacturing the wafer 1 in this manner, first, the hoop material 7 is supplied to the mold device 15 shown in FIG. 10, and the gate formed between the fixed mold 16 and the movable mold 17 of the mold device 15 is gated. 18
The molten resin 19 is injected through the. Along with this, the center contact
The molten resin 19 flows from the supporting portion 9 side of the 2c to the supporting portion 8 side of the common contacts 2a and 2b, thereby filling the cavity with the molten resin 19, and then, after the molten resin 19 is cured, the mold apparatus. After obtaining the wafer 1 in the state shown in FIG. 9 by releasing from the mold 15, the supporting portions 8, 9 projecting from both side ends of the wafer 1 are cut at predetermined positions.

[Problems to be solved by the invention]

By the way, according to the prior art, when the molten resin 19 injected from the gate 18 passes near the support portion 9 of the central contact 2c, the support portion 9 and the bent portion 12 have arrows 20 in FIG.
, The support portion 9, the bent portion 12, and the center contact 2c are deformed from the state shown by the two-dot chain line to the state shown by the solid line. As a result, the support section 9 is fixed to the fixed mold. 16
As a result, the resin flow path between the support portion 9 and the movable mold 17 is widened, and the flow in this portion is accelerated, so that a portion of the molten resin 19 covers the contact surface of the central contact 2c. There is a problem that the so-called center contact 2c is covered with resin. Then, when resin covering occurs on the contact surface of the central contact 2c, there is a concern that a contact failure between the central contact 2c and the movable contact 3 may be caused.

The present invention has been made in view of such circumstances in the prior art, and an object of the present invention is to provide a method of manufacturing a switch wafer that can prevent resin covering of fixed contacts.

[Means for solving the problem]

In order to achieve this object, a switch wafer according to the present invention comprises a hoop material having a support portion extending in a longitudinal direction, a fixed contact connected to the support portion via a bent portion, and the hoop material. The fixed contact is exposed on the inner bottom surface of the molten resin, and a concave portion is provided on the inner bottom surface at a position corresponding to a support portion at the root of the bent portion. It is.

In order to achieve the above object, a method for manufacturing a switch wafer according to the present invention includes a support portion extending in a longitudinal direction,
A switch wafer for supplying a hoop material having fixed contacts connected to the supporting portion via a bent portion to a mold device, and filling a cavity of the mold device with a molten resin to form a switch wafer; In the manufacturing method of (1), a pin for adjusting the flow of the molten resin is provided at a position corresponding to a support portion at the base of the bent portion.

[Action]

The present invention, as described above, the inner bottom surface of the molten resin,
Since a concave portion is provided at a position corresponding to the support portion at the base of the bent portion, the flow of the molten resin near the support portion is adjusted by the concave portion during molding, so that the molten resin flows with the flow of the molten resin. Forces do not act excessively on the supports and bends. Further, according to the present invention, since the pin is provided at a position corresponding to the support portion at the base of the bent portion, the hoop material is supplied to the mold device, and when filling the cavity of the mold device with the molten resin, Since the flow of the molten resin in the vicinity of the support portion is adjusted by the pins, the force accompanying the flow of the molten resin does not excessively act on the support portion and the bent portion.
As a result, since the support portion, the bent portion, and the fixed contact do not greatly deform, the resin flow path between the support portion and the mold is maintained at a predetermined width, and the molten resin is melted. Since the resin can flow at a predetermined flow rate, it is possible to prevent the fixed contact from covering the resin.

〔Example〕

Hereinafter, an embodiment of a method for manufacturing a switch wafer of the present invention will be described with reference to the drawings.

1 to 6 are views for explaining an embodiment of a method for manufacturing a switch wafer according to the present invention. FIG. 1 is a longitudinal sectional view showing a state in which a cavity of a mold apparatus is filled with a molten resin.
2 is a longitudinal sectional view of the hoop material corresponding to FIG. 1 in a longitudinal direction, FIG. 3 is a plan view showing a state of a wafer after molding, and FIG.
FIG. 5 is a rear view of the wafer, FIG. 5 is a side view of the wafer, and FIG. 6 is an enlarged sectional view of a main part of the mold apparatus shown in FIG.

The wafer 21 shown in FIG. 3 is filled in the hoop material 7 having the same configuration as the conventional one shown in FIG. 8 and the cavity 23 of the mold apparatus 22 shown in FIG. 1 and FIG. It consists of a molten resin 24. A concave portion 25 formed by the head of a pin 31 described later is provided on the inner bottom surface where the opening of the wafer 21 is desired. 4 and 5, a projection 26 extends in a direction perpendicular to the longitudinal direction of the hoop material 7, as shown in FIGS.

As shown in FIG. 1, a mold apparatus 22 for molding such a wafer 21 is fed through a cavity 23 formed on a joint surface between a fixed mold 27 and a movable mold 28 via a runner 29. A gate 30 for injecting the molten resin 24 into the cavity 23,
A pin 31 is provided at a position corresponding to the support portion 9 at the base of the bent portion 12 and adjusts the flow of the molten resin 24. As shown in FIG. 2, the mold apparatus 22 includes a pilot pin 32 provided on a fixed mold 27, and a movable mold 28.
And a protruding pin 33 provided at the bottom.

In this embodiment, when manufacturing the wafer 21, first, the hoop material 7 is supplied to the mold device 22, and the pilot pin 32 is inserted into the hole 13 of the connecting portion 14 of the hoop material 7 and positioned. The hoop material 7 is sandwiched between the fixed mold 27 and the movable mold 28, and in this state, the molten resin 24 fed through the runner 29 is injected from the gate 30 to the cavity 23. Along with this, the molten resin 24 flows from the support portion 9 side of the central contact 2c to the support portion 8 side of the common contacts 2a and 2b, and the molten resin 24
The cavity 23 is filled with. At this time, the flow of the molten resin 24 near the support portion 9 is adjusted by the pin 35,
The force accompanying the flow of the molten resin 24 is applied to the support portion 9 and the bent portion.
Since it does not work excessively on the bent portion 12, the bent portion 12 and the support portion 9 are not greatly deformed. Next, the molten resin 24
After curing, the movable mold 28 is lowered, and the wafer 21 to which the movable mold 28 is attached is protruded and pushed up by the pins 33 to be released from the mold apparatus 22.
The support portions 8 and 9 projecting from both side ends are cut at predetermined positions.

In the embodiment configured as described above, the molten resin 24 can be caused to flow at a predetermined flow rate while the resin flow path between the support portion 9 of the hoop material 7 and the movable mold 28 is maintained at a predetermined width. It is possible to prevent resin covering of the contact surface of the center contact 9 and the like. Further, since a part of the molten resin 24 flows along the protrusion 26 formed on the fixed mold 27 side, it is possible to adjust the flow of the molten resin 24 on the fixed mold 27 side to a better one. it can.

〔The invention's effect〕

Since the present invention is configured as described above, the molten resin is caused to flow at a predetermined flow rate while the resin flow path between the support portion of the hoop material and the mold is maintained at a predetermined width.
It is possible to prevent the fixed contact from covering the resin, and thus to obtain a good switch wafer that does not cause a contact failure between the fixed contact and the movable contact.

[Brief description of the drawings]

1 to 6 are views for explaining an embodiment of a method for manufacturing a switch wafer according to the present invention. FIG. 1 is a longitudinal sectional view showing a state in which a cavity of a mold apparatus is filled with a molten resin.
2 is a longitudinal sectional view of the hoop material corresponding to FIG. 1 in a longitudinal direction, FIG. 3 is a plan view showing a state of a wafer after molding, and FIG.
FIG. 5 is a back view of the wafer, FIG. 5 is a side view of the wafer, FIG. 6 is an enlarged sectional view of a main part of the mold apparatus shown in FIG. 1, and FIGS. 7 to 10 are methods for manufacturing a switch wafer. FIG. 7 is a cross-sectional view showing a configuration of a push button switch provided with a switch wafer, FIG. 8 is a plan view of a hoop material, and FIG. 9 shows a state of the wafer after molding. Plan view, 10th
The figure is a sectional view showing a state in which the cavity of the mold apparatus is filled with a molten resin. 2a, 2b ... common contact (fixed contact), 2c ... center contact (fixed contact), 7 ... hoop material, 8, 9 ... support part, 12
…… Bending part, 21 …… Wafer, 22 …… Die equipment, 23 ……
Cavity, 24 ... Molten resin, 25 ... Recess, 26 ... Protrusion, 31 ... Pin.

Claims (2)

(57) [Claims] 1. A hoop material having a support portion extending in a longitudinal direction, a fixed contact connected to the support portion via a bent portion, and a molten resin formed integrally with the hoop material,
A switch wafer, wherein the fixed contact is exposed on an inner bottom surface of the molten resin, and a concave portion is provided on the inner bottom surface at a position corresponding to a support portion at a root of the bent portion. 2. A hoop material having a support extending in a longitudinal direction and a fixed contact connected to the support via a bent portion is supplied to a mold device, and molten resin is poured into a cavity of the mold device. A method of manufacturing a switch wafer, wherein the switch wafer is filled to form a switch wafer, wherein a pin for adjusting the flow of the molten resin is provided at a position corresponding to a support portion at a root of the bent portion. Method for manufacturing wafers.