JPH0334017Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field In this invention, by pressing down the plunger which is biased outward, the snap piece made of spring material operates as a snap action, and the movable piece The present invention relates to a switch that can switch a movable contact from a normally closed contact side to a normally open contact side.

(b) Prior art In the above-mentioned switch, the contacts are melted by the spark generated when switching the contacts, and the normally closed contacts that are normally in contact are welded by this melting, making it impossible to switch the contacts. The incidence of this welding increases with age.

Conventionally, there have been switches that have a means for separating this welding. That is, as shown in FIG. 1, the center part of the movable piece 3 made of a plate spring material is cut into the recesses 2, 2 formed in the side surface of the plunger 1 which is urged upward by a suitable spring. Snap pieces 4, 4 formed by notching and pulling up are locked and formed so that a snap action action occurs, and movable contacts 5, 5 are fixed to this movable piece 3, and the movable contacts 5, 5 are By placing the normally closed contacts 6, 6 facing each other on the lower side and the normally open contacts 7, 7 facing above, by pressing down the plunger 1, the movable contacts 5,
5 constitutes a switch structure in which normally closed contacts 6, 6 are switched to normally open contacts 7, 7, and on the lower surface side of the movable piece 3, there are release levers 9, 9 pivotally mounted on shaft parts 8, 8. At the same time, a cam surface 10 formed at the lower part of the plunger 1 is provided on the lower end side of the release levers 9, 9.
forming protrusions 11, 11 which are rotated at 10;
The free ends 12, 12 of the release levers 9, 9 are located close to the movable contacts 5, 5.

In the switch configured in this way, by pressing down the plunger, the movable contacts 5, 5 are switched from normally closed contacts 6, 6 to normally open contacts 7, 7, and at the same time, the cam surfaces 10, 10 of the plunger 1 are switched from normally closed contacts 6, 6 to normally open contacts 7, 7. contacts the protrusions 11, 11 of the separation levers 9, 9 and rotates them, so when the movable contacts 5, 5 are welded to the normally closed contacts 6, 6, the separation levers 9, 9 As the free end portions rotate, the free end portions 12, 12 push up the movable piece 3 from the lower surface side, and separate the welding of the movable contacts 5, 5.

(c) Problems to be solved by the invention However, in the case of this switch, each time the plunger 1 is pressed down, the protrusions 11, 1 of the release levers 9, 9
1 comes into contact with the cam surfaces 10, 10 of the plunger 1, and since this contact is due to friction, by the time the cam surface 10 and the protrusion 11 are worn out and separated due to age, the welding has already occurred. The degree of mutual wear is large,
There is play between them and they rattle, which makes it impossible to separate them strongly, resulting in a problem that a sufficient welding/separating action cannot be obtained.

Further, since the separation lever 9 produces the separation action by rotation, the rotation trajectory of the free ends 12, 12 becomes an arc shape, and a slight vertical component with respect to the movable contacts 5, 5 of the movable piece 3 is generated. , much of the force is released to the inside of the circular motion, and as a result, sufficient acting force is not obtained on the movable contacts 5, 5, so a reliable welding/separating action cannot be obtained. Moreover, since the load of welding and separation is applied to the shaft parts 8, 8, there is a problem that the shaft parts 8, 8 are easily damaged.

Therefore, the object of this invention is to provide a switch whose welding/separating structure is free from damage due to age, and in which the welding/separating action of the contacts can be reliably obtained.

(d) Means for Solving the Problems This invention consists of forming the plunger into upper and lower halves in the pressing direction, and creating a rack between the racks carved on the opposing sides so that the upper and lower plungers overlap each other. The interposed pinion transmits the downward movement of the upper plunger to the lower plunger, and the lower plunger
A movable piece is attached via a snap piece so that a snap action action occurs when the upper plunger is pressed down, and a movable piece is attached to the upper plunger in the vicinity of a movable contact of the movable piece in the opening direction of the movable contact. The switch is characterized by a series of opening levers that move in a direction parallel to the switch.

(E) Function In the switch of this invention, when the upper plunger is pressed down, the lower plunger moves upward by the rack and pinion, thereby switching the movable contact. If the movable contact is welded at this time, the separation rod of the upper plunger pushes down the movable contact in parallel to separate it.

(f) Effect of the invention According to this invention, the opening rod is near the movable contact and moves in a direction parallel to the opening direction of the movable contact, so a force perpendicular to the movable piece is applied. Therefore, there is no loss of acting force and a reliable welding/separating action can be obtained.

Furthermore, the movement of the opening rod is achieved by direct pressing of the plunger or by rolling power transmission through the meshing of the rack and pinion. Even when the contacts become welded over time, their shape does not change and they work reliably to provide good welding and separation effects.

(G) Embodiment An embodiment of this invention will be described below in detail based on the drawings.

The drawings show a switch, and in FIGS. 2 to 4, the switch 21 includes a case 22, an upper plunger 23, a lower plunger 24, a snap piece 25, a movable piece 26, movable contacts 27, 27, and a normally closed contact 28. ,2
8. Consisting of normally open contacts 29, 29,
The case 22 is formed into a concave shape with a bottom wall, and a suitable cover is fitted onto the open surface of the case 22.

The above-mentioned upper plunger 23 has a hemispherical upper end to form the operation part 30, and a prismatic shaft part to be vertically slidably inserted into the upper part of the case 22. A return spring (not shown) is interposed therein to urge the upper plunger 23 upward and to position the upper plunger 23 at its upper limit.

The lower end of the above-mentioned upper plunger 23 is located in the recessed space of the case 22, and this end is bifurcated in the front-rear direction to form rack rods 31, 31.
Furthermore, the ends of the rack rods 31, 31 are branched to the left and right, respectively, and the left and right ends protrude downward to form separation rods 32, 32 in series.

The separation rods 32, 32 are located near the movable contacts 27, 27 of the movable piece 26, and the racks 33, 33 are located on the outer surfaces of the aforementioned rack rods 31, 31.
is engraved.

The upper end of the lower plunger 24 is bifurcated in the left-right direction, and extends upward into a rack rod 34,
34 are arranged in series, and these rack rods 34, 34 are arranged in the same way as the rack rods 31, 31 of the upper plunger 23.
The racks 35, 35 are engraved on the inside.

Pinions 36, 36 are interposed between the rack rods 31, 31, 34, 34, and the pinions 36, 36 are pivotally supported by the case 22.
When the operation part 30 of the upper plunger 23 is pressed down,
The downward movement of the upper plunger 23 is transmitted to the lower plunger 2 via the racks 33, 35 and the pinion 36.
4 and moves upward.

Note that the lower end of the lower plunger 24 is connected to the case 22.
It is supported by a guide portion 37 formed in .

On both sides of the intermediate portion of the lower plunger 24, there are recesses 3 for locking one ends of the snap pieces 25, 25.
8 and 38 are formed, and the middle part of the movable piece 26 is cut out in the shape of a frame so that the shaft part of the lower plunger 24 can be inserted therein, and the snap pieces 25 and 25 can perform a snap action operation. The other ends of the snap pieces 25, 25 are secured to both ends of the notch.

Movable contacts 27, 2 are provided at both ends of the above-mentioned movable piece 26.
7 is fixed, and these movable contacts 27, 2
Above 7, normally closed contacts 28, 28 are provided facing each other, and these normally closed contacts 28, 28 are fixed to fixed terminals 39, 39 which are press-fitted and fixed to the case 22, and these fixed terminals 39, 39 are fixed to the case 22. Attachment screws 40, 40 for fixing a connection line (not shown) are screwed together.

Further, below the movable contacts 27, 27, normally open contacts 29, 29 face each other, and these normally open contacts 29, 29
are fixed to fixed terminals 41, 41 that are press-fitted into the case 22, for example, and these fixed terminals 41, 41
Attachment screws 42, 42 for fixing connection wires (not shown) are screwed together.

In the switch 21 configured in this way, the upper plunger 23 moves downward by pressing down the upper end operating portion 30 of the upper plunger 23, and this downward movement causes the lower The plunger 24 moves upward, and this upward movement causes the snap piece 25 to act as a snap action, causing the movable piece 26 to move downward.
The normally open contacts 29, 29 are switched from the side to the normally open contacts 29, 29 side.

Furthermore, when the upper plunger 23 is released from being pressed down, the upper plunger 23 moves upward, and this upward movement causes the lower plunger 24 to move downward, and this downward movement causes the snap piece 25 to perform a reverse snap action movement, making it movable. The piece 26 moves upward, and the movable contacts 27, 27 become normally open contacts 29, 29.
It is switched from the side to the normally closed contacts 28, 28 side.

On the other hand, the opening levers 32, 32 move downward as the upper plunger 23 is pressed down, so that the movable contacts 27, 27 are connected to the normally closed contact 2, as shown in FIG.
When the movable contacts 27, 28 are welded,
27 can be pushed down in the same direction as the opening direction to open it.

In this case, since the separation rod 32 is directly connected to the upper plunger 23, there is no wear and tear due to age, and it functions reliably.

In the above embodiment, the movable piece 26 is provided on the lower plunger 24 side, but it can also be provided on the upper plunger 23 side. In this case, the normally closed contact 28 and the normally open contact 29 are vertically opposite in position, so the separation rod 32 is formed on the lower plunger 24 side. Since the separation rod 32 is movable by rolling power transmission by a rack and a pinion, there is no mutual wear over time, and the welding and separation action can be reliably obtained.

[Brief explanation of drawings]

FIG. 1 is a partial front view of a switch equipped with conventional welding and separating means. The following shows an example of this idea,
Figure 2 is a front view of the switch. FIG. 3 is a partial perspective view of the main part. FIG. 4 is a front view showing the operating state. 21... Switch, 23... Upper plunger, 24
...Lower plunger, 25...Snap piece, 26...
...Movable piece, 27...Movable contact, 28...Normally closed contact, 29...Normally open contact, 30...Operation unit, 31,
34...Rack rod, 32...Opening rod, 33,35
...Rack, 36...Pinion.

Claims (1)

[Claim for Utility Model Registration] When the operating part set on one end of the plunger is pressed down, the snap piece is reversed by snap action action, and the movable contact of the movable piece is changed from the normally closed contact side to the normally open contact side. The switch is configured such that the plunger is divided into upper and lower halves in the pressing direction, and the upper and lower plungers overlap each other and are engraved on opposing sides, and a pinion is interposed between these racks. The pressing motion of the upper plunger is transmitted to the lower plunger, and the pressing motion of the upper plunger is transmitted to the lower plunger.
The movable piece is attached to the upper plunger through a snap piece so as to generate a snap action, and the upper plunger is provided in a direction parallel to the opening direction of the movable contact in the vicinity of the movable contact of the movable piece. A switch with a series of opening rods that operate on both sides.