JP2008078090A - Push-button switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a push-button switch having excellent durability. <P>SOLUTION: The push-button switch is composed of a base 10 having a common fixed contact point 12 at a bottom center of a recess part 11 and having fixed contact points 13, 14 at a corner of the recess part 11, a reversing spring 30 which is a movable contact point and is locked in the recess part 11 and of which an outer circumferential part contacts with the fixed contact points 13, 14 and a push button 40 to push down the reversing spring 30. Especially, between the fixed contact points 13, 14 of the base 10 and the reversing spring 30, there is arranged a relay ring-shaped terminal for preventing abrasion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a push button switch, and more particularly to a push button switch having excellent durability.

  Conventionally, as a push button switch, for example, as shown in FIGS. 1 to 4 of Patent Document 1, a case 1, a movable contact 5, a driving body 6 having an operation unit 7, a cover plate 8, (See Patent Document 1).

In the push button switch, the central portion of the movable contact 5 is pushed down by operating the drive unit 6 by pushing down the operation unit 7. Then, when the central portion of the movable contact 5 is lowered to a predetermined position, the central portion is reversed and contacts the fixed contact 4 provided on the bottom surface of the recess of the case 1, and the fixed contact 4 is connected via the movable contact 5. And the fixed contact 3 are conducted.
JP-A 64-7442

  However, in the above-described push button switch, when the central portion of the movable contact 5 is pushed down by the driver 6, the outer peripheral edge slides on the upper surface of the fixed contact 3. For this reason, for example, if the surface of the fixed contact 3 is gold-plated, the gold-plating is scraped and the contact resistance increases. Further, when the fixed contact 3 is brass and the movable contact 5 is made of stainless steel or phosphor bronze, there is a problem that the movable contact 5 is easily worn away and is not durable.

  In view of the above problems, an object of the present invention is to provide a push button switch having excellent durability.

  The push button switch according to the present invention has a common fixed contact at the center of the bottom surface of the recess and a base in which the fixed contact is arranged at the corner of the recess, and fits in the recess in order to solve the above-mentioned problem And a push button switch comprising a reversing spring whose outer peripheral edge is a movable contact that contacts the fixed contact, and a push button that pushes down the reversing spring, between the fixed contact of the base and the reversing spring. The relay terminal for preventing wear is arranged.

According to the present invention, the outer peripheral edge of the reversing spring slides on the upper surface of the wear preventing relay terminal, so that the fixed contact is not easily worn. In particular, since the pressure of the reversing spring is reduced and the frictional force is reduced, it is more difficult to wear and the durability is improved.
Further, by appropriately changing the thickness dimension of the wear preventing relay terminal, the spring characteristics can be changed, and a desired operation feeling can be obtained.

As an embodiment according to the present invention, the relay terminal for wear prevention may have an annular shape.
According to this embodiment, the directionality at the time of assembly is lost, and the frictional force at the time of contact becomes uniform.

As another embodiment according to the present invention, metal plating may be applied to the surface of the wear preventing relay terminal.
According to the present embodiment, there is an effect that a push button switch with high conductivity and high contact reliability can be obtained.

An embodiment of a push button switch according to the present invention will be described with reference to the accompanying drawings of FIGS.
As shown in FIGS. 1 and 2, the present embodiment is generally composed of a base 10, a relay ring terminal 20 for preventing wear, a reversing spring 30 that is a movable contact, a push button 40, and a cover 50. ing.

  As shown in FIG. 3, the base 10 is a flat rectangular resin molded product, and a common fixed contact 12 is projected by insert molding at the center of the bottom of a circular recess 11 provided at the center thereof. Fixed contacts 13 and 14 are embedded in the corners of the recess 11 with the common fixed contact 12 in between. The common fixed contact 12 is pulled out from the lower surface of the base 10 and is connected to terminals 15 and 15 which are bent and raised along opposing outer surfaces. On the other hand, the fixed contacts 13 and 14 are pulled out from the lower surface of the base 10 and are connected to terminals 16 and 17 bent up along the opposing outer surfaces. In addition, a positioning step 18 is formed at the top corner of the base 10, and a positioning cut is provided on the inner peripheral surface of the recess 11 at a position facing the common fixed contact 12 therebetween. Notch portions 11a and 11b are respectively provided. Further, a locking claw portion 10 a is formed on the opposite outer surface edge of the base 10.

  As shown in FIG. 2, the wear prevention relay annular terminal 20 can be fitted into the recess 11 and has an outer peripheral shape covering the fixed contacts 13, 14, and a pair of positionings on the outer peripheral edge thereof. A projecting portion 21 is provided. The wear prevention relay annular terminal 20 is preferably made of a material having high hardness and excellent conductivity, such as phosphor bronze or stainless steel. Further, the relay annular terminal 20 does not need to be a continuous annular shape, and may be a discontinuous arc. Further, the relay annular terminal 20 does not need to have a flat cross section, and may have a circular cross section.

  The reversing spring 30 is formed by pressing a thin disc-shaped conductive material into a dome shape and functions as a movable contact. The reversing spring 30 has an outer peripheral shape that can be fitted into the recess 11 and is provided with a pair of positioning protrusions 31 at opposing outer peripheral edge portions.

  The push button 40 has an outer peripheral shape capable of covering the upper surface of the base 10, and is provided with an operation protrusion 41 protruding in the vertical direction at the center thereof, and a positioning step for the base 10 at the lower corner of the push button 40. A protrusion 42 that can be fitted to the portion 18 is provided.

  The cover 50 has a planar shape capable of covering the base 10, has a fitting hole 51 in the center thereof, and has a notch for locking at the corners of the bent portions 52 extending from opposite side edges. A portion 53 is provided.

  Next, the push button switch composed of the above-described components is provided with the protrusion 21 of the relay ring terminal 20 for preventing wear and the protrusion 31 of the reversing spring 30 at the notches 11 a and 11 b provided in the recess 11 of the base 10. Are assembled and sequentially assembled. Next, after the positioning step 18 provided on the upper surface of the base 10 is fitted and positioned with the projection 42 of the push button 40, the cover 50 is covered and the operation projection 41 is fitted into the fitting hole 51. When the notch 53 of the cover 50 is engaged with the locking claw 10a of the base 10, the assembling work is completed.

  Before the operation of the push button 40, as shown in FIG. 4A, the reversing spring 30 pushes the operation protrusion 41 of the push button 40 upward, and the outer peripheral edge of the reversing spring 30 is a relay ring terminal for wear prevention. While being in contact with the fixed contacts 13, 14 through 20, the central portion is separated from the common fixed contact 12.

  When the operation protrusion 41 of the push button 40 is pushed down, the central portion of the reversing spring 30 is pushed down, and when it is lowered to a predetermined position, the central portion of the reversing spring 30 is reversed and contacts the common fixed contact 12. The common fixed contact 12 and the fixed contacts 13 and 14 are electrically connected through the wear preventing relay annular terminal 20 and the reversing spring 30.

  Next, when the pressure on the push button 40 is released, the push button 40 is pushed up by the spring force of the reversing spring 30, the central portion of the reversing spring 30 is released from the common fixed contact 12, and the original state is restored.

  According to the present embodiment, even if the reversing spring 30 is pushed down and its outer peripheral edge slides outward, it moves on the relay ring terminal 20 for preventing hard wear, and the pressure of the reversing spring is reduced. Since the frictional force is small, wear hardly occurs. For this reason, a push button switch having higher durability than the conventional example can be obtained.

  Further, according to the present embodiment, if the thickness dimension of the wear preventing relay annular terminal 20 is appropriately selected, the spring characteristics can be changed as shown in FIG. For this reason, there is an advantage that a push button switch having a desired operation feeling can be obtained.

  Needless to say, the push button switch according to the present invention is not limited to the above-described embodiment, but may be applied to other push button switches.

It is a perspective view which shows embodiment of the pushbutton switch concerning this invention. It is a disassembled perspective view of the pushbutton switch shown in FIG. FIG. 3 is a plan view of the base shown in FIG. 2. FIGS. A and B are a cross-sectional view and a cross-sectional perspective view taken along line AA before the operation of the push button switch shown in FIG. FIGS. A and B are an AA line sectional view and a sectional perspective view after the operation of the push button switch shown in FIG. It is a graph for demonstrating an operation feeling. It is a perspective view.

Explanation of symbols

10: Base 11: Recess 12: Common fixed contact 13, 14: Fixed contact 15, 16, 17: Terminal 20: Relay ring terminal for wear prevention 21: Projection for positioning 30: Reversing spring (movable contact)
31: Projection for positioning 40: Push button 41: Projection for operation 50: Cover

Claims (3)

A base having a common fixed contact at the center of the bottom of the recess, a fixed contact disposed at a corner of the recess, and a movable contact that fits into the recess and has an outer peripheral edge in contact with the fixed contact. In a push button switch comprising a reversing spring and a push button that pushes down the reversing spring,
A push button switch, characterized in that a relay terminal for wear prevention is arranged between the fixed contact of the base and the reversing spring.   2. The push button switch according to claim 1, wherein the wear preventing relay terminal has an annular shape.   The push button switch according to claim 1 or 2, wherein the surface of the relay terminal for wear prevention is metal-plated.

Images