JPH037853Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a push button switch that is attached to a keyboard and used as a keyboard switch. Regarding switch units.

(b) Prior Art The above-mentioned push button switch is provided with a plunger that moves up and down when the key top is pressed, and a contact that is operated by the up and down movement of the plunger.

(c) Problems to be solved by the invention However, when the above-mentioned plunger is operated, abrasion powder is generated, and this abrasion powder adheres to the contact area, resulting in poor contact between the contacts. It had a point.

The object of this invention is to provide a switch unit for a push button switch that reliably prevents abrasion powder generated by the plunger from adhering to the contact portion.

(d) Means for solving the problem This invention forms a contact internal structure in which the contact portion of the movable contact and the fixed contact is covered by a unit case and a unit cover, and the contact part of the unit cover is enclosed by the movable contact. The switch unit is a push button switch in which a part of the periphery of the movable contact is cut out, and an operating part for operating the movable contact from the outside is formed by utilizing the elasticity of the material.

(E) Operation In the switch unit of the push button switch of this invention, when the operating section is operated from the outside by the vertical movement of the plunger, the movable contact is operated inside the operating section.

(f) Effect of the invention According to this invention, the switch unit has a contact internal structure in which a movable contact and a fixed contact are enclosed by a unit case and a unit cover, and the switch unit has a contact internal structure in which a movable contact and a fixed contact are enclosed by a unit case and a unit cover, and the switch unit has a contact internal structure in which a movable contact and a fixed contact are enclosed by a unit case and a unit cover. Since the contacts are operated from the outside, even if abrasion powder or debris from the plunger occurs inside the switch, it is prevented from entering the contact area inside the switch unit, and the abrasion powder is prevented from entering the contact area. It can reliably prevent adhesion and poor contact. A highly reliable switch can be obtained.

Furthermore, since each terminal can be formed of a material that is thicker than the movable contact, it is possible to prevent the terminal from being bent when attached to a printed circuit board, for example, and thereby reducing workability.

(g) Example of the invention An example of the invention will be described below in detail based on the drawings.

The drawings show a push button switch, and in FIGS. 1 and 2, the push button switch 11 includes a key top 12, a switch cover 13, a plunger 14, a spring 15, a switch case 16, an operating piece 17, and a switch unit 18. It is structured as follows.

The aforementioned switch case 16 has a concave storage section 19.
A receiving portion 20 for the spring 15 is provided protruding from the center bottom of the inside. Furthermore, guide rails 21 are integrally formed on opposing sides of the interior to guide the vertical movement of the plunger 14 by contacting its four corners, and the upper ends of these guide rails are connected to the openings 24 of the switch cover 13, which will be described later. It extends to the top surface. Also, on the side of the plunger 14, there is a protrusion 22 for regulating the upward movement of the plunger 14.
is formed.

The aforementioned plunger 14 has a receiving recess 23 for the spring 15 formed on its bottom surface, and the spring 15 is interposed between this receiving recess 23 and the aforementioned receiving portion 20.

The above-mentioned switch cover 13 has an opening 24 formed in its center upper surface, and locking pieces 25, 25 extending downward are formed in series on opposing side edges. , 25 has a locking hole 26,
26 are formed, and when these locking holes 26, 26 are forcibly fitted into the locking protrusions 27, 27 formed on the outer surface of the switch case 16, they are locked to each other, and the switch cover 13 is closed to the switch. Case 1
It is fixed at 6.

The rim of the opening 24 of the switch cover 13 is provided with the protrusions 22, 22 of the plunger 14.
A regulating edge 28, 2 facing and abutting against the head of the
8, and these regulating edges 28, 28 regulate upward movement of the plunger 14 and prevent the plunger 14 from coming off.

The upper half of the plunger 14 is provided to protrude from the opening 24 of the switch cover 13, and a mounting hole 29 for the key top 12 is formed in the upper surface of the plunger 14. The section 30 is fitted. And key top 1
2, the plunger 14 is moved up and down.

Inside the switch case 16 on one side of the plunger 14, a partition wall 31 whose upper end extends to approximately the center of the switch case 16 is connected to the bottom of the switch case 16, and between the partition wall 31 and the side wall, the above-mentioned switch unit is connected. 18 are arranged.

The aforementioned operation piece 17 is made of an elastic plate spring material, and has a locking part 32 on its upper part that is locked to the upper part of the switch unit 18, and also extends in an inclined shape toward the plunger 14 side. A bifurcated movable piece 3 that is in contact with the opposite lower edge of the plunger 14
3, and a protrusion 34 is formed on the back side thereof. This operation piece 17 is the plunger 14.
When the plunger 14 moves downward, the movable piece 33 is pressed down, thereby moving the protrusion 34 outward. In other words, the vertical movement of the plunger 14 is converted into a lateral movement, and this lateral movement causes the protrusion 34 to move outward. 34 operates an operating section 38 of the switch unit 18, which will be described later.

The aforementioned switch unit 18 is shown in FIGS. 3 and 4.
As shown in the figure, the unit case 35 and the unit cover 36 form a unit main body 37 having a contact interior structure that encloses the contact part. An operating portion 38 is formed in the center of the holder, and the operating portion 38 is formed by cutting out both sides and the upper three sides of the operating portion 38 so as to be able to restore its original shape by utilizing the elasticity of the material.

The above-mentioned unit case 35 has three terminals 3.
9, 40, and 40 are formed as inserts, and the central terminal 39 has a connecting portion 41 exposed at the center inside the unit case 35, and the lower end of the movable contact 42 is caulked to this connecting portion 41. Fixed. Further, the left and right terminals 40, 40 are internally connected to a fixed contact 43 formed exposed on the inside upper part of the unit case 35.
3 faces the upper end side contact portion of the above-mentioned movable contact 42, the movable contact 42 and the fixed contact 43 are normally separated, and when the above-mentioned operating section 38 is pressed down inside the unit, the movable contact 42 and the fixed contact 43 are , the movable contact 42 can come into contact with the fixed contact 43 (see FIG. 5).

The unit case 35 and unit cover 36 are fitted and fixed as appropriate.

Further, when the switch unit 18 is housed in the partition wall 31 of the switch case 16, the three terminals 39, 40, 40 extending downward protrude downward through the through hole 44 formed at the bottom of the switch case 16. , and the operation section 3 of the switch unit 18
8 is stored facing the plunger 14 side.

Push button switch 11 configured in this way
Since the plunger 14 is urged upward by the spring 15, the key top 12 is normally positioned upward as shown in FIG.

Then, when the key top 12 is pressed down, the plunger 14 is guided by the guide rails 21 and lowered, and the lower edge of the plunger 14 facing the operation piece 17 presses down the movable piece 33 of the operation piece 17, which moves the switch unit. With this movement, the protrusion 34 of the movable piece 33 is moved to the switch unit 1 side.
8, and this operation pushes down the internal movable contact 42, and this movable contact 42 comes into contact with the fixed contact 43 and is operated as a switch.

In the above-mentioned switch unit 18, even if abrasion powder from the plunger 14 is generated inside the switch 11, since the switch unit 18 has a contact internal structure, the abrasion powder is transferred to the internal contact 4.
It is possible to prevent the adhesive from adhering to the 2nd and 43rd portions.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, in which Fig. 1 is an exploded perspective view of a push button switch, Fig. 2 is a longitudinal sectional view thereof, Fig. 3 is an exploded perspective view of the switch unit, and Fig. 4 is a longitudinal sectional view thereof. 5 are circuit diagrams of the switch unit. 11...Push button switch, 14...Plunger, 18...Switch unit, 35...Unit case, 36...Unit cover, 38...
...Operation unit, 39, 40...Terminal, 41...Connection part, 42...Movable contact, 43...Fixed contact.

Claims (1)

[Scope of Claim for Utility Model Registration] A switch unit of a push-button switch incorporating the switch unit that is operated by the operation of a plunger that moves up and down, and in which three terminals arranged in parallel are housed in a unit case made of resin material. The terminals on both sides are internally connected to a fixed contact formed exposed on one side of the upper part of the unit case, and the center terminal has a connecting part exposed below the fixed contact and is connected to this connecting part. One end of the movable contact is fixed and its free end faces the fixed contact, and a unit cover made of a resin material is fitted on the exposed side of each contact of the unit case to form a contact interior structure, and the unit cover has the following features: A switch unit of a push-button switch, wherein a portion of the periphery of the movable contact facing the movable contact is cut out except for a part to form an operating portion for operating the movable contact from the outside by utilizing the elasticity of the material.