Push switch

Abstract

To inhibit a hook of a metal cover from digging into a claw part of a housing during reflow.SOLUTION: A push switch includes: a housing having a storage part; a movable contact member provided in the storage part; a fixed contact member which is provided facing the movable contact member on an inner bottom surface of the storage part and has an external connection terminal; an operation member which presses the movable contact member; and a metal cover which covers the housing. The housing has, on a side surface of the housing, a claw part on which a hook of the metal cover hooks. The claw part is provided with a reinforcement part.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a push switch.

Background Art

[0002] Patent Document 1 below discloses a technique for fixing a frame to a case in a state where a rubber stem is sandwiched between the upper part of the case and the frame by hooking a hook of the frame on a claw part of the case in a push switch.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the technique of Patent Document 1, when the case softens due to the heat applied during reflow, there is a risk that the hook bites into the lower surface of the claw part.

Means for Solving the Problems

[0005] A push switch according to an embodiment includes a housing having a storage portion, a movable contact member provided inside the storage portion, a fixed contact member provided opposite to the movable contact member on the inner bottom surface of the storage portion and having an external connection terminal, an operation member for pressing the movable contact member, and a metal cover covering the housing. The housing has a claw portion for hooking a hook of the metal cover on a side surface of the housing, and a reinforcing portion is provided on the claw portion.

Effects of the Invention

[0006] According to a push switch according to an embodiment, it is possible to suppress the hook of the metal cover from biting into the claw portion of the housing during reflow.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0008] Hereinafter, an embodiment will be described with reference to the drawings. In the following description, for convenience, the Z-axis direction in the drawing is taken as the vertical direction, the Y-axis direction in the drawing is taken as the left-right direction, and the X-axis direction in the drawing is taken as the front-back direction. However, the positive Z-axis direction is upward, the positive Y-axis direction is rightward, and the positive X-axis direction is forward.

[0009] (Outline of Push Switch 100) FIG. 1 is an external perspective view of a push switch 100 according to an embodiment. As shown in FIG. 1, in the push switch 100, the upper surface 110A of the housing 110 is covered by a rubber stem 140 and a metal cover 120. A hemispherical operation portion 141 protruding convexly upward (in the positive Z-axis direction) is provided at the central portion of the rubber stem 140.

[0010] The operating portion 141 of the rubber stem 140 penetrates through the circular opening 120A formed in the metal cover 120 and protrudes upward (in the positive Z-axis direction) from the metal cover 120. As a result, the push switch 100 can be pressed downward (in the negative Z-axis direction) by the operating portion 141 of the rubber stem 140, and by this pressing operation, it can be switched from the switch-off state to the switch-on state.

[0011] (Configuration of Push Switch 100) FIG. 2 is an exploded perspective view of a push switch 100 according to an embodiment. FIG. 3 is a cross-sectional view of a push switch 100 according to an embodiment. As shown in FIGS. 2 and 3, the push switch 100 includes, in order from the lower side (negative Z-axis side) in the figure, a housing 110, a metal inverted dome 130, a rubber stem 140, and a metal cover 120.

[0012] The housing 110 is a container-shaped member having a thin rectangular parallelepiped shape in the vertical direction (Z-axis direction). The housing 110 has a substantially square shape in a top view. The housing 110 has a storage portion 110B that is recessed downward from the upper surface 110A. A metal inverted dome 130 is accommodated inside the storage portion 110B. For example, the housing 110 is formed by insert molding using a relatively hard insulating material (e.g., hard resin, etc.).

[0013] On each of the pair of left and right side surfaces of the housing 110, claw portions 111 protruding outward are formed. When the metal cover 120 is attached to the upper surface 110A of the housing 110, the claw portions 111 are fitted into the opening 121A of the hook 121 of the metal cover 120, whereby the hook 121 can be hooked to fix the metal cover 120 to the housing 110.

[0014] On the inner bottom surface of the storage portion 110B of the housing 110, a first fixed contact 112A and four second fixed contacts 113A are provided.

[0015] The first fixed contact 112A is provided at the center of the inner bottom surface of the storage portion 110B and is provided to face the back surface of the top of the metal inverted dome 130. The first fixed contact 112A is integrally provided with a single first fixed contact member 112 made of metal and in the shape of a plate.

[0016] The four second fixed contacts 113A are provided around the first fixed contact 112A on the inner bottom surface of the storage portion 110B and are provided at the four corner portions on the inner bottom surface of the storage portion 110B. The four second fixed contacts 113A are integrally provided with a single second fixed contact member 113 made of metal and in the shape of a plate. Each of the four second fixed contacts 113A has each of the four legs 131 of the metal inverted dome 130 placed thereon.

[0017] Both the first fixed contact member 112 and the second fixed contact member 113 are formed using a conductive plate material (for example, a metal plate) and are embedded in the housing 110 by insert molding.

[0018] The metal inverted dome 130 is an example of a "movable contact member" and is a dome-shaped member capable of inverting operation. The metal inverted dome 130 is a member made of a thin metal plate disposed in the storage portion 110B of the housing 110. The metal inverted dome 130 is circular in top view and has a dome shape convex upward (in the positive Z-axis direction).

[0019] Four legs 131 protruding outward in the radial direction are provided at 90° intervals on the outer peripheral edge of the metal inverted dome 130. Each of the four legs 131 is placed on each of the four second fixed contacts 113A provided at the four corner portions of the inner bottom surface of the storage portion 110B. Thereby, the metal inverted dome 130 is stably supported at four points by the four second fixed contacts 113A and is electrically connected to the second fixed contacts 113A.

[0020] The metal reverse dome 130 is a so-called "reverse spring". When a pressing operation is performed by the operation portion 141 of the rubber stem 140, the top (central portion) is pressed downward by the central projection 143 of the rubber stem 140, and when the predetermined operation load is exceeded, the top suddenly elastically deforms (reversing operation) into a concave shape. As a result, the metal reverse dome 130 contacts the first fixed contact 112A at a portion on the back side of the top and is electrically connected to the first fixed contact 112A. As a result, the metal reverse dome 130 can conduct the first fixed contact 112A and the second fixed contact 113A to each other via the metal reverse dome 130. When the pressing operation by the operation portion 141 of the rubber stem 140 is released, the metal reverse dome 130 returns to its original convex shape by the elastic force.

[0021] In the present embodiment, the push switch 100 has two metal reverse domes 130 overlapping each other in order to adjust the operation load characteristics of the pressing operation. However, the push switch 100 is not limited to this, and the push switch 100 may have one or three or more metal reverse domes 130.

[0022] The rubber stem 140 is an example of an "operation member" and is a member that is pressed downward by an operator. The rubber stem 140 is placed on the upper surface 110A of the housing 110 and is fixed by the metal cover 120 in a state where the storage portion 110B of the housing 110 is closed. The rubber stem 140 is formed using an elastic material (for example, rubber, silicon, etc.). The rubber stem 140 has an operation portion 141, a base portion 142, and a central projection 143.

[0023] The operation portion 141 is provided at the center of the rubber stem 140 and has a hemispherical shape protruding upward from the base portion 142. The operation portion 141 penetrates the opening 120A of the metal cover 120 and is subjected to a pressing operation by an operator. An elastic deformation portion 141A having a relatively thin thickness is provided in an annular shape around the operation portion 141. The operation portion 141 can move up and down due to elastic deformation of the elastic deformation portion 141A.

[0024] The base 142 is a flat plate-shaped portion provided around the operation unit 141. The base 142 is provided integrally with the operation unit 141 and supports the operation unit 141 so as to be movable up and down. In a top view, the outer shape of the base 142 has substantially the same shape as the outer shape of the housing 110 (that is, generally a square shape). The rubber stem 140 is fixed to the upper surface 110A of the housing 110 by the base 142 being pressed from above by the metal cover 120.

[0025] The central protrusion 143 is provided so as to protrude downward from the bottom surface of the operation unit 141 and has a hemispherical shape with a diameter smaller than that of the operation unit 141. When a pressing operation is performed by the operation unit 141, the central protrusion 143 moves downward integrally with the operation unit 141 and presses the top of the metal inversion dome 130.

[0026] The metal cover 120 is a metal and flat plate-shaped member. The metal cover 120 is fixedly attached to the upper surface 110A of the housing 110 with the base 142 of the rubber stem 140 sandwiched therebetween, thereby fixing the rubber stem 140 to the upper surface 110A of the housing 110.

[0027] For example, the metal cover 120 is formed by a metal plate being processed by a processing method such as pressing. In a top view, a circular opening 120A is formed at the center of the metal cover 120 for protruding the operation unit 141 of the rubber stem 140 upward.

[0028] Also, on each of the pair of left and right sides at the outer peripheral edge of the metal cover 120, downwardly hanging hooks 121 are provided. The hook 121 has an opening 121A, and a claw portion 111 provided on the side surface of the housing 110 is fitted into the opening 121A. Thereby, the hook 121 is hooked on the claw portion 111, and the metal cover 120 can be fixed to the housing 110.

[0029] Also, a bent portion 121B bent in a V shape toward the inside (the center side of the housing 110) is provided in a portion of the hook 121 below the opening 121A.

[0030] (Configuration of the first fixed contact member 112 and the second fixed contact member 113) FIG. 4 is a plan view of a housing 110 included in a push switch 100 according to an embodiment. FIG. 5 is a plan view of a first fixed contact member 112 and a second fixed contact member 113 included in the housing 110 according to an embodiment.

[0031] As shown in FIGS. 4 and 5, a first fixed contact member 112 and a second fixed contact member 113 are integrally provided in the housing 110 by insert molding. The first fixed contact member 112 and the second fixed contact member 113 are formed by processing a metal plate. A part of the first fixed contact member 112 and the second fixed contact member 113 is embedded in the housing 110, and the remaining part is exposed from the housing 110.

[0032] The first fixed contact member 112 has a plate shape extending in the front-rear direction (X-axis direction), and has a substantially circular first fixed contact 112A at the rear end portion (the end portion on the X side). The first fixed contact 112A is provided at the center of the inner bottom surface of the storage portion 110B of the housing 110, and the metal inverted dome 130 faces the back side portion of the top. The first fixed contact 112A is provided to protrude upward from the upper surface of the first fixed contact member 112. Thus, when the metal inverted dome 130 performs an inversion operation, the back side portion of the top of the metal inverted dome 130 locally contacts the first fixed contact 112A.

[0033] The first fixed contact member 112 has an external connection terminal 112B at the front end portion (the end portion on the positive side of the X axis). As shown in FIG. 4, the external connection terminal 112B is provided to protrude from the side surface on the front side (positive side of the X axis) of the housing 110.

[0034] The second fixed contact member 113 is provided at a portion on the rear side (negative X-axis side) of the inner bottom surface of the housing portion 110B of the housing 110, and includes a plate-shaped first portion 113P1 that linearly extends in the left-right direction (Y-axis direction), a plate-shaped second portion 113P2 that is provided at a portion on the left side (negative Y-axis side) of the inner bottom surface of the housing portion 110B of the housing 110 and linearly extends in the front-rear direction (X-axis direction), and a plate-shaped third portion 113P3 that is provided at a portion on the right side (positive Y-axis side) of the inner bottom surface of the housing portion 110B of the housing 110 and linearly extends in the front-rear direction (X-axis direction). That is, the second fixed contact member 113 has a shape along three sides of the inner bottom surface of the housing portion 110B of the housing 110 so as to surround the first fixed contact 112A.

[0035] Rectangular second fixed contacts 113A are provided at each of the front end and the rear end of the second portion 113P2 and at each of the front end and the rear end of the third portion 113P3. That is, the second fixed contact member 113 has four second fixed contacts 113A at four corner portions of the inner bottom surface of the housing portion 110B of the housing 110. Each of the four second fixed contacts 113A projects upward from the upper surface of the second fixed contact member 113. Thereby, when the metal inversion dome 130 is disposed in the housing portion 110B of the housing 110, each of the four leg portions 131 of the metal inversion dome 130 locally contacts each of the four second fixed contacts 113A.

[0036] The second fixed contact member 113 has external connection terminals 113B at each of the front end and the rear end of the second portion 113P2 and at each of the front end and the rear end of the third portion 113P3. As shown in FIG. 4, two of the external connection terminals 113B project from the side surface on the front side (positive X-axis side) of the housing 110, and the other two external connection terminals 113B project from the side surface on the rear side (negative X-axis side) of the housing 110.

[0037] Further, the second fixed contact member 113 has reinforcing portions 113C protruding outward in the left - right direction (Y - axis direction) at the middle portion of the second part 113P2 in the front - rear direction (X - axis direction) and at the middle portion of the third part 113P3 in the front - rear direction (X - axis direction). Each reinforcing portion 113C is integrally formed with the claw portion 111 of the housing 110 by insert molding and constitutes a part of the lower surface of the claw portion 111 of the housing 110.

[0038] (Operation of Push Switch 100) When the pressing operation by the operation portion 141 of the rubber stem 140 is not performed, the push switch 100 according to an embodiment is in an initial state where the operation portion 141 is at the highest position, and the metal inverted dome 130 is in an initial state convex upward. At this time, the metal inverted dome 130 is in contact with the second fixed contact 113A but not in contact with the first fixed contact 112A. That is, the second fixed contact 113A and the first fixed contact 112A are not electrically connected to each other. Therefore, when the pressing operation by the operation portion 141 of the rubber stem 140 is not performed, the push switch 100 according to an embodiment is in an off state.

[0039] When the pressing operation is performed on the operation portion 141 of the rubber stem 140, the central protrusion 143 of the rubber stem 140 pushes down the top portion (the portion around the opening 130A) of the metal inverted dome 130. As a result, the metal inverted dome 130 is elastically deformed (inverted operation) into a concave shape, and the back - side portion of the top of the metal inverted dome 130 comes into contact with the first fixed contact 112A. As a result, in the push switch 100 according to an embodiment, the first fixed contact 112A and the four second fixed contacts 113A are electrically connected to each other via the metal inverted dome 130, and the switch is turned on.

[0040] FIG. 6 is a perspective cross-sectional view seen from below of a push switch 100 (in a state without a metal cover 120) according to an embodiment. FIG. 7 is a perspective cross-sectional view seen from below of a push switch 100 (in a state with a metal cover 120) according to an embodiment.

[0041] As shown in FIG. 6, on each of the pair of left and right claw portions 111 of the housing 110, a reinforcing portion 113C of the second fixed contact member 113 is integrally provided so as to form a part of the lower surface of the claw portion 111.

[0042] Then, as shown in FIG. 7, when the hook 121 of the metal cover 120 is hooked on each of the pair of left and right claw portions 111 of the housing 110, the V-shaped bent portion 121B provided on the hook 121 abuts against the reinforcing portion 113C provided on the lower surface of the claw portion 111. Thereby, the hook 121 is hooked on the lower surface of the claw portion 111, and the upward (positive Z-axis direction) movement of the hook 121 with respect to the claw portion 111 is restricted.

[0043] Here, the metal cover 120 is hooked on the pair of left and right claw portions 111 of the housing 110 in a state where the base portion 142 of the rubber stem 140 is compressed. Thereby, due to the elastic force of the base portion 142 of the rubber stem 140, the metal cover 120 is biased upward, and a pressing force from the bent portion 121B of the hook 121 is always applied to the lower surface of the claw portion 111. For this reason, when the housing 110 softens due to the heat applied during reflow, there is a risk that the bent portion 121B of the hook 121 bites into the lower surface of the claw portion 111. However, in the push switch 100 according to an embodiment, since the lower surface of the claw portion 111 is reinforced by the reinforcing portion 113C, even when the claw portion 111 softens due to the heat during reflow, it is possible to suppress the bent portion 121B of the hook 121 from biting into the lower surface of the claw portion 111.

[0044] In particular, in the push switch 100 according to an embodiment, since the reinforcing portion 113C is made of a metal material, the reinforcing portion 113C itself has high strength, and thus the strength of the claw portion 111 can be further increased.

[0045] Also, in the push switch 100 according to one embodiment, since the reinforcing portion 113C is provided integrally with the second fixed contact member 113, when the bent portion 121B of the hook 121 contacts the reinforcing portion 113C, the metal cover 120 and the second fixed contact member 113 can be electrically connected to each other. Therefore, in the push switch 100 according to one embodiment, by grounding the external connection terminal 113B of the second fixed contact member 113 to the ground, the static electricity generated on the metal cover 120 can be discharged to the ground through the second fixed contact member 113.

[0046] Also, in the push switch 100 according to one embodiment, since the reinforcing portion 113C is provided at the same height position as the main body portion of the second fixed contact member 113, the bending operation of the second fixed contact member 113 is not required, and the reinforcing portion 113C can be easily provided on the second fixed contact member 113.

[0047] As described above, one embodiment of the present invention has been described in detail. However, the present invention is not limited to these embodiments, and various modifications or changes can be made within the scope of the gist of the present invention described in the claims.

Description of Reference Numerals

[0048] 100 Push switch 110 Housing 110A Upper surface 110B Storage portion 111 Claw portion 112 First fixed contact member 112A First fixed contact 112B External connection terminal 113 Second fixed contact member 113A Second fixed contact 113B External connection terminal 113C Reinforcing portion 113P1 First portion 113P2 Second portion 113P3 Third portion 120 Metal cover 120A opening 121 Hook 121A opening 121B bending part 130 Metal reversing dome (moving contact member) 131 Leg 140 Rubber stem 141 Operating part 141A Elastic deformation part 142 Base 143 Central protrusion

Claims

1. A housing having a storage portion, A movable contact member provided inside the storage portion, A fixed contact member provided to face the movable contact member on the inner bottom surface of the storage portion and having an external connection terminal, An operating member for pressing the movable contact member, And a metal cover covering the housing are provided. The housing has a claw portion on a side surface of the housing for hooking a hook of the metal cover, The claw portion is provided with a reinforcing portion A push switch characterized by that.

2. The reinforcing portion is made of a metal material The push switch according to claim 1, characterized by that.

3. The reinforcing portion is provided integrally with the fixed contact member The push switch according to claim 2, characterized by that.

4. The reinforcing portion is in contact with the hook of the metal cover The push switch according to claim 3, characterized by that.

5. As the operating member, a rubber stem disposed between the housing and the metal cover is provided The push switch according to claim 1, characterized by that.

6. A part of the fixed contact member is embedded in the housing The push switch according to claim 1, characterized by that.

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