JPH0319147Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an improvement of the contactor in a pushbutton switch, and allows the contactor, which is integrally molded from a relatively soft elastic material, to be easily incorporated into the switch body using an automatic machine. The purpose is to

Recently, contacts made of soft silicone rubber or the like have been used to obtain switches that produce a click feeling and have a small operating force. Figure 1 shows
An example of such a conventional contact installed in a recess 2 on the lower surface of a plunger 1 is shown. The contactor 3 has an annular part 3b connected by a conical thin part 3a and a downwardly protruding part 3c, and a contact part 3d made of conductive rubber is provided on the lower surface of the annular part 3b.
are integrally formed.

In order to assemble the contacts 3 into the recess 2 of the plunger 1 using an automatic machine, pick up the contacts 3 aligned in a certain direction with a parts feeder one by one with a chuck, and place them in the recess 2 of the plunger 1. A possible method is to move the chuck to above the chuck, then lower the chuck and insert it into the recess 2. However, the contact 3, which is made of soft rubber with a hardness of about 60, is easily deformed and has large friction, so it has the disadvantage that it is easily clogged near the exit of the parts feeder. Furthermore, when inserting the contact into the recess 2, the protrusion 3c is held by the chuck and the contact 3 is inserted into the recess 2.
However, if the contact 3 is soft, even if part of the annular portion 3b hits the edge of the recess 2 and the chuck cannot be installed correctly, the movement of the chuck cannot be prevented, making it impossible to detect installation failure. The problem is that there is no. For this reason, in the past, the contacts had to be assembled manually, resulting in a decrease in work efficiency.

In addition, in conventional contacts, the annular part expands laterally when the switch is operated, and if left as is, the click feeling becomes weak. By suppressing the spread with the side walls of the recess, the click feeling is prevented from decreasing. Therefore, the magnitude of the click feeling when the switch is operated depends on the size of the gap between the side wall of the recess in which the contact is installed and the annular section, which is the main cause of variations in the operating force of the switch. This is the cause.

The purpose of the present invention is to eliminate such conventional drawbacks, to provide a contact that can easily automate the work of assembling it into a plunger or case, and to reduce variations in the operating force of the switch. It is characterized by a structure in which the outer peripheral surface of the contactor is covered with a hard ring member.

2 and 3 show an embodiment of the contactor according to the present invention. The contactor 10 includes a conical flexible thin-walled portion 12, and an annular portion 14 and a downwardly protruding portion 16 are made of soft rubber or synthetic resin with a hardness of about 60 at the periphery and center of the thin-walled portion 12, respectively. Molded in one piece from elastic material. The outer peripheral surface and lower surface of the annular portion 14 are covered with a ring member 18 made of hard conductive rubber having a hardness of about 90. As a material for this ring member 18, silicone rubber mixed with carbon or the like is suitable.

FIG. 4 shows an example of a push button switch incorporating this contactor 10. The contactor 10 is fitted into a recess 22 provided on the lower surface of the plunger 20. The plunger 20 is movable up and down inside the case 30, and when the plunger 20 is not in operation, the contact 10 is placed inside the case 30.
The plunger 20 is supported by its elasticity. Note that 40 and 50 are fixed contact pieces installed in the case 30, and 60 is a top plate. In this switch, when the plunger 20 is pushed down, the thin wall portion 12 is reversed, producing a click feeling, and at the same time, the pair of fixed contact pieces 40, 50 are short-circuited by the lowered ring member 18, and the switch is turned on. .

5 and 6 show other embodiments of the contactor. This contactor 70 also has a substantially conical thin section 72, and an annular section 74 is integrally molded on the periphery of the thin section 72 from a soft elastic material.
Reference numeral 76 denotes a downwardly protruding portion that is integrally fixed to the top of the thin wall portion 72, and in this example, is made of a conductive rubber material and forms a contact portion. Similar to the contactor 10 described above, the outer peripheral surface of the annular portion 74 is covered with a ring member 78 made of a hard elastic material. Unlike ring member 18, ring member 78 in this case need not be a conductive material.

FIG. 7 shows an example of a switch incorporating a contactor 70. In this case, the contactor 70 is assembled so that a ring member 78 is fitted into a recess 92 of a case 90. When the plunger 80 placed on the contact 70 is pushed down to operate the switch, the thin portion 72
is distorted, causing a clicking sensation, and the lowered protrusion 76 short-circuits the fixed contact pieces 100 and 110.

In this manner, the contactor according to the present invention has the advantage that it is difficult to cause undesirable deformation because the outer circumferential surface of the annular portion is covered with the ring member made of an elastic material that is harder than the thin-walled portion. Therefore, not only can the parts feeder smoothly supply the contact, but also the work of inserting the contact held by the chuck into the recess of the plunger or case can be done reliably because the edges of the contact are hard. It is extremely effective in automating the process of assembling contacts, such as being able to detect them immediately.

Further, since the contactor according to the present invention is provided with a hard ring member around the periphery, lateral expansion during operation is restricted. Therefore, it is less affected by the recess dimensions of the plunger and case.
This also has the effect of reducing variations in the operating force of the switch.

[Brief explanation of drawings]

Fig. 1 is a front sectional view showing a conventional example, Fig. 2 is a perspective view showing an embodiment of the present invention, Fig. 3 is a front sectional view of the same, and Fig. 4 is a front view of a switch incorporating the same contactor. 5 is a perspective view showing another embodiment of the present invention, FIG. 6 is a front sectional view of the same, and FIG. 7 is a front sectional view of a switch incorporating this contactor. 10,70...Contactor, 12,72...Thin wall part, 14,74...Annular part, 16,76...Protrusion part, 18,78...Ring member.

Claims (1)

[Scope of utility model registration request] comprising a substantially conical flexible thin-walled portion, and an annular portion that is thicker than the thin-walled portion and located at the periphery of the thin-walled portion;
In a switch contactor in which the thin part and the annular part are integrally molded from an elastic material such as rubber or synthetic resin, the outer peripheral surface of the annular part is covered with a ring member made of a second elastic material harder than the elastic material. A contact characterized by being coated.