Push switch

Abstract

To provide a two-stage switch using a relatively small number of stationary contacts.SOLUTION: A push switch comprises: a housing including a recess; a rubber stem provided on the recess, including a central projection protruding downward, and including a conductive part in a lower end of the central projection; a movable contact which is provided in the recess and dome-shaped so as to perform an inverting action and includes in a central part an opening through which the central projection can be inserted; a first stationary contact which is provided being opposed with the conductive part on an inner bottom face of the recess; and a second stationary contact which is provided in contact with the movable contact around the first stationary contact on the inner bottom face of the recess. The first stationary contact includes a plurality of contact parts which is divided into each other. When a pressing operation of the rubber stem for a first stroke amount is performed, the conductive part of the rubber stem passes the opening of the movable contact and is brought into contact with each of the plurality of contact parts, thereby providing a first conductive state where the plurality of contact parts is conducted with one another via the conductive part.SELECTED DRAWING: Figure 7

Description

Technical Field

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

Background Art

[0002] Patent Document 1 below discloses a two-stage push button switch member having a structure in which a first switch member and a second switch member are stacked in the pressing direction, executing a first input by depressing the second switch member, and then executing a next input by depressing the first switch member that has received the pressing from the second switch member.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the technology of Patent Document 1 conducts the contact electrode 11 and the contact electrode 12 in the first input, and conducts the contact electrode 13 and the contact electrode 14 in the next input. That is, different contact electrodes are conducted in the first input and the next input, so a relatively large number of contact electrodes are required.

Means for Solving the Problems

[0005] The push switch according to one embodiment includes a housing having a recess, a rubber stem provided on the recess and having a central protrusion protruding downward, the rubber stem having a conductive portion at the lower end of the central protrusion, a movable contact provided in the recess, having a domed shape that can be inverted, and having an opening through which the central protrusion can be inserted at the center, a first fixed contact provided facing the conductive portion on the inner bottom surface of the recess, and a second fixed contact provided in contact with the movable contact around the first fixed contact on the inner bottom surface of the recess. The first fixed contact has a plurality of contact portions that are divided from each other. When a pressing operation of a first stroke amount of the rubber stem is performed, the conductive portion of the rubber stem passes through the opening of the movable contact and contacts each of the plurality of contact portions, so that the plurality of contact portions are electrically connected to each other via the conductive portion, resulting in a first conductive state.

Effects of the Invention

[0006] According to the push switch according to one embodiment, a two-stage switch can be realized using a relatively small number of fixed contacts.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

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Figure 4

Figure 5

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Figure 7

Figure 8

Best 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 the vertical direction, the Y-axis direction in the drawing is the left-right direction, and the X-axis direction in the drawing is the front-back direction. However, the positive direction of the Z-axis is upward, the positive direction of the Y-axis is to the right, and the positive direction of the X-axis is forward.

[0009] (Overview 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, the push switch 100 generally has a thin rectangular parallelepiped shape in the vertical direction (Z-axis direction) and has a generally square shape in a top view.

[0010] As shown in FIG. 1, for the push switch 100, the upper surface 110A of the housing 110 is covered by the rubber stem 140 and the frame 120. An operation portion 141 protruding convexly upward (in the positive Z-axis direction) is provided at the central portion of the rubber stem 140.

[0011] The operation portion 141 of the rubber stem 140 penetrates through the circular opening 120A formed in the frame 120 and protrudes above (in the positive Z-axis direction) the frame 120. Thereby, the push switch 100 can be pressed downward (in the negative Z-axis direction) by the operation portion 141 of the rubber stem 140, and by this pressing operation, it can be switched from the switch-off state to the first conduction state and the second conduction state.

[0012] (Configuration of Push Switch 100) FIG. 2 is an exploded perspective view of the push switch 100 according to an embodiment viewed from above. FIG. 3 is an exploded perspective view of the push switch 100 according to an embodiment viewed from below. FIG. 4 is a cross-sectional view of the push switch 100 according to an embodiment. As shown in FIGS. 2 to 4, the push switch 100 includes, in order from the lower side (negative Z-side) in the drawing, a housing 110, a metal inverted dome 130, a rubber stem 140, and a frame 120.

[0013] 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 generally square shape when viewed from above. The housing 110 has a recessed portion 110B that is recessed downward from the upper surface 110A. A metal reversing dome 130 is housed in the recessed portion 110B. For example, the housing 110 is formed by insert molding using a relatively hard insulating material (such as hard resin).

[0014] On each of the pair of left and right side surfaces of the housing 110, a claw portion 111 that protrudes outward is formed. When the frame 120 is attached to the upper surface 110A of the housing 110, the claw portion 111 is fitted into the opening 121A of the hook 121 of the frame 120 and engages with the hook 121, thereby fixing the frame 120 to the housing 110.

[0015] On the inner bottom surface of the recessed portion 110B of the housing 110, a first fixed contact 112 and two second fixed contacts 113 are provided. The first fixed contact 112 is provided at the center of the inner bottom surface of the recessed portion 110B and is provided opposite to the conductive portion 143A of the rubber stem 140. Each of the two second fixed contacts 113 is provided around the first fixed contact 112 on the inner bottom surface of the recessed portion 110B and is provided at each of the two corner portions on the inner bottom surface of the recessed portion 110B. Each of the two legs 133 of the metal reversing dome 130 is placed on each of the two second fixed contacts 113. The first fixed contact 112 and the second fixed contacts 113 are both formed using a conductive plate material (such as a metal plate) and are embedded in the housing 110 by insert molding.

[0016] The metal reversing dome 130 is an example of a "movable contact" and is a dome-shaped member capable of reversing operation. The metal reversing dome 130 is a member made of a thin metal plate disposed in the recess 110B of the housing 110. The metal reversing dome 130 has, at its central portion, a dome portion 131 that is circular in top view and convex upward (in the positive Z-axis direction). A circular opening 130A is formed at the central portion of the dome portion 131. Further, the metal reversing dome 130 has, around the dome portion 131, a horizontal edge portion 132 that surrounds the dome portion 131. By having the edge portion 132, the metal reversing dome 130 has an outer shape that is generally square in top view.

[0017] At each of the four corner portions on the outer peripheral edge of the metal reversing dome 130, each of the four leg portions 133 protruding outward in the radial direction is provided. Of the four leg portions 133, the two leg portions 133 on the negative X-axis side are placed on each of the two second fixed contacts 113 provided on the inner bottom surface of the recess 110B. Of the four leg portions 133, the two leg portions 133 on the positive X-axis side are placed on each of the two pedestal portions 110C provided on the inner bottom surface of the recess 110B. Thereby, the metal reversing dome 130 is stably supported at four points by the inner bottom surface of the recess 110B and is electrically connected to the second fixed contact 113.

[0018] The metal reversing dome 130 is a so-called "reversing spring". When a pressing operation is performed on the operation portion 141 of the rubber stem 140, the top portion (the portion around the opening 130A) is pressed downward by the first pressing portion 144 of the rubber stem 140, and when a predetermined operating load is exceeded, the top portion suddenly elastically deforms (reverses) into a concave shape. Thereby, the metal reversing dome 130 comes into contact with the first fixed contact 112 at the back side of the top portion and is electrically connected to the first fixed contact 112. As a result, the metal reversing dome 130 can conduct the first fixed contact 112 and the second fixed contact 113 to each other via the metal reversing dome 130. Note that the metal reversing dome 130 returns to its original convex shape by the elastic force when the pressing operation by the operation portion 141 of the rubber stem 140 is released.

[0019] The rubber stem 140 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 fixed by the frame 120 in a state where the recess 110B of the housing 110 is closed. The rubber stem 140 is formed using an elastic material (e.g., rubber, silicon, etc.). The rubber stem 140 has an operation part 141, a base part 142, a central protrusion part 143, a first pressing part 144, and four second pressing parts 145.

[0020] The operation part 141 is provided at the center of the rubber stem 140 and has a cylindrical shape protruding upward from the base part 142. The operation part 141 passes through the opening 120A and is pressed by the operator. An elastic deformation part 141A with relatively thin thickness is provided in an annular shape around the operation part 141. The operation part 141 can move up and down when the elastic deformation part 141A elastically deforms.

[0021] The base part 142 is a flat part provided around the operation part 141. The base part 142 is provided integrally with the operation part 141 and supports the operation part 141 so that it can move up and down. In a top view, the outer shape of the base part 142 has the same shape as the outer shape of the housing 110 (i.e., generally square). The rubber stem 140 is fixed to the upper surface 110A of the housing 110 when the base part 142 is pressed from above by the frame 120.

[0022] The central protrusion part 143 is provided protruding downward from the bottom surface of the operation part 141 and has a cylindrical shape with a smaller diameter than the operation part 141. The central protrusion part 143 moves up and down integrally with the operation part 141 when a pressing operation is performed by the operation part 141.

[0023] On the bottom surface of the central protrusion 143, a disc-shaped conductive part 143A having conductivity is provided. The conductive part 143A is provided opposite to the two contact parts 112A of the first fixed contact 112. When the pressing operation by the operation part 141 is performed and the central protrusion 143 moves downward, the conductive part 143A comes into contact with each of the two contact parts 112A of the first fixed contact 112. Thereby, the conductive part 143A can conduct the two contact parts 112A with each other. As an example, the conductive part 143A is made of a conductive metal.

[0024] The first pressing part 144 is provided to protrude downward from the bottom surface of the operation part 141 and has an annular shape surrounding the central protrusion 143 in a bottom view. When the pressing operation by the operation part 141 is performed, the first pressing part 144 presses the top part (the part around the opening 130A) of the metal inverted dome 130.

[0025] The four second pressing parts 145 are provided at the four corner parts on the lower surface of the base part 142. Each of the four second pressing parts 145 has a hemispherical shape protruding downward from the lower surface of the base part 142. The four second pressing parts 145 press the four leg parts 133 of the metal inverted dome 130 from above. Thereby, the four second pressing parts 145 can press the four leg parts 133 against the two second fixed contacts 113 and the two pedestal parts 110C to fix the metal inverted dome 130.

[0026] The frame 120 is a metal and flat plate-shaped member. The frame 120 is fixedly attached to the upper surface 110A of the housing 110 with the base part 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 frame 120 is formed by processing a metal plate by a processing method such as press working. In a top view, a circular opening 120A is formed at the center of the frame 120 for protruding the operation portion 141 of the rubber stem 140 upward. Further, hooks 121 that hang downward are provided on each of a pair of left and right sides at the outer peripheral edge of the frame 120. 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 can fix the frame 120 to the housing 110.

[0028] (Configuration of the first fixed contact member 114 and the second fixed contact member 116) FIG. 5 is a plan view of a housing 110 included in a push switch 100 according to an embodiment. FIG. 6 is a plan view of first fixed contact members 114, 115 and a second fixed contact member 116 included in the housing 110 according to an embodiment.

[0029] As shown in FIGS. 5 and 6, two first fixed contact members 114, 115 and a second fixed contact member 116 are integrally provided in the housing 110 by insert molding. The two first fixed contact members 114, 115 and the second fixed contact member 116 are formed by processing a metal plate.

[0030] The two first fixed contact members 114, 115 are arranged side by side in the left - right direction (Y - axis direction) at a portion on the front side (positive X - axis side) of the housing 110 and have a left - right symmetric shape with respect to each other. The first fixed contact member 114 is provided on the right side (positive Y - axis side), and the first fixed contact member 115 is provided on the left side (negative Y - axis side).

[0031] Each of the two first fixed contact members 114 and 115 has a plate shape extending in the front-rear direction (X-axis direction), and has a semi-circular contact portion 112A constituting the first fixed contact 112 at the rear end portion (the end portion on the X side). As shown in FIG. 5, the two contact portions 112A of the first fixed contact 112 are arranged spaced apart from each other at the central portion of the inner bottom surface of the recess 110B of the housing 110.

[0032] On each of the two contact portions 112A, two pedestal-shaped contact portions 112Aa are provided so as to protrude upward from the upper surface of the contact portion 112A. Thereby, when the pressing operation of the rubber stem 140 is performed on each of the two contact portions 112A, the conductive portion 143A of the rubber stem 140 comes into local contact with each of the two contact portions 112Aa. That is, the first fixed contact 112 has four contact portions 112Aa. In the example shown in FIGS. 5 and 6, when viewed from above, the four contact portions 112Aa are arranged in a cross shape, and each of the four contact portions 112Aa has a rectangular shape.

[0033] The first fixed contact member 114 has an external connection terminal 114A at the front end portion (the end portion on the positive side of the X axis). The first fixed contact member 115 has an external connection terminal 115A at the front end portion (the end portion on the positive side of the X axis). The external connection terminals 114A and 115A are provided so as to protrude from the side surface on the front side (the positive side of the X axis) of the housing 110.

[0034] The second fixed contact member 116 is provided at the rear portion (the negative side of the X axis) of the housing 110. The second fixed contact member 116 has a plate shape extending in the left-right direction (Y-axis direction) and has a left-right symmetric shape.

[0035] The second fixed contact member 116 has pedestal-shaped second fixed contacts 113 provided so as to protrude upward from the upper surface of the second fixed contact member 116 at each of the right end (the end on the positive Y-axis side) and the left end (the end on the negative Y-axis side). That is, the second fixed contact member 116 has four second fixed contacts 113. As shown in FIG. 5, one of the second fixed contacts 113 is disposed at the right rear corner of the inner bottom surface of the recess 110B of the housing 110, and the other second fixed contact 113 is disposed at the left rear corner of the inner bottom surface of the recess 110B of the housing 110. Thereby, when the metal inverted dome 130 is disposed in the recess 110B of the housing 110, each of the two legs 133 on the rear side (negative X-axis side) of the metal inverted dome 130 locally contacts each of the two second fixed contacts 113. In the example shown in FIGS. 5 and 6, when viewed from above, each of the two second fixed contacts 113 has a rectangular shape.

[0036] The second fixed contact member 116 has an external connection terminal 116A at the right end (the end on the positive Y-axis side). Further, the second fixed contact member 116 has an external connection terminal 116B at the left end (the end on the negative Y-axis side). The external connection terminals 116A and 116B are provided to protrude from the side surface on the rear side (negative X-axis side) of the housing 110.

[0037] (Operation of Push Switch 100) FIG. 7 is a cross-sectional view showing a first conductive state of the push switch 100 according to an embodiment. FIG. 8 is a cross-sectional view showing a second conductive state of the push switch 100 according to an embodiment.

[0038] As shown in FIGS. 1 and 4, when the push switch 100 according to an embodiment is not being pressed by the operating portion 141 of the rubber stem 140, the operating portion 141 is in the initial state at the highest position, and the metal inverted dome 130 is in the initial state convex upward. At this time, the metal inverted dome 130 is in contact with the second fixed contact 113, but neither the metal inverted dome 130 nor the conductive portion 143A of the rubber stem 140 is in contact with the first fixed contact 112. That is, the two contact portions 112A are not electrically connected to each other, and the second fixed contact 113 and the first fixed contact 112 are not electrically connected to each other. For this reason, when the push switch 100 according to an embodiment is not being pressed by the operating portion 141 of the rubber stem 140, it is in the off state.

[0039] Then, as shown in FIG. 7, when the push switch 100 according to an embodiment is pressed by the operating portion 141 of the rubber stem 140 by the first stroke amount, the central protrusion 143 of the rubber stem 140 passes through the opening 130A of the metal inverted dome 130, and the conductive portion 143A provided at the lower end of the central protrusion 143 contacts each of the two contact portions 112A provided on the inner bottom surface of the recess 110B of the housing 110. Specifically, the conductive portion 143A contacts the two contact portions 112Aa of one contact portion 112A and the two contact portions 112Aa of the other contact portion 112A. Thereby, in the push switch 100 according to an embodiment, the two contact portions 112A are electrically connected to each other via the conductive portion 143A, and the first conductive state is achieved. That is, in the first conductive state, the external connection terminal 114A and the external connection terminal 115A are electrically connected to each other.

[0040] At this time, the push switch 100 according to an embodiment can exhibit a bottoming feeling with respect to the pressing operation by the operating portion 141 of the rubber stem 140 when the conductive portion 143A of the rubber stem 140 abuts against each of the two contact portions 112A. Therefore, the push switch 100 according to an embodiment can allow the operator to tactilely recognize that the first conductive state has been switched to.

[0041] Subsequently, when a pressing operation equal to or greater than the first stroke amount is performed on the operation portion 141 of the rubber stem 140, the first pressing portion 144 of the rubber stem 140 presses down the top portion (the portion around the opening 130A) of the metal inverted dome 130 in a push switch 100 according to an embodiment.

[0042] Then, as shown in FIG. 8, when a pressing operation with a second stroke amount greater than the first stroke amount is performed on the operation portion 141 of the rubber stem 140 in the push switch 100 according to an embodiment, the top portion of the metal inverted dome 130 is elastically deformed (inverted operation) in a concave shape. As a result, the back side portion of the top portion of the metal inverted dome 130 comes into contact with each of the two contact portions 112A.

[0043] As a result, in the push switch 100 according to an embodiment, the two contact portions 112A and the two second fixed contacts 113 are electrically connected to each other via the metal inverted dome 130, thereby entering a second conductive state. That is, in the second conductive state, the external connection terminal 114A and the external connection terminal 115A are electrically connected to the external connection terminal 116A and the external connection terminal 116B.

[0044] At this time, the push switch 100 according to an embodiment can exhibit a click feeling with respect to the pressing operation by the operation portion 141 of the rubber stem 140 due to the inverted operation of the metal inverted dome 130. Therefore, the push switch 100 according to an embodiment can allow an operator to tactilely recognize that the second conductive state has been switched to.

[0045] Note that when the pressing operation by the operation portion 141 of the rubber stem 140 is released in the push switch 100 according to an embodiment, the rubber stem 140 returns to its initial state by its own elastic force, and the metal inverted dome 130 returns to its original convex shape by its own elastic force. As a result, the push switch 100 according to an embodiment returns to the switch-off state shown in FIGS. 1 and 4.

[0046] In the pressing operation by the operation portion 141 of the rubber stem 140 described above, until the operation amount reaches the first stroke amount, only the rubber stem 140 is gradually elastically deformed, so the operation load gradually increases. Therefore, the operator can switch the push switch 100 to the first conduction state with a relatively light pressing operation.

[0047] And, from when the operation amount reaches the first stroke amount until it reaches the second stroke amount, since the metal inversion dome 130 is elastically deformed in addition to the rubber stem 140, the operation load rapidly increases. Therefore, the operator can switch the push switch 100 to the second conduction state with a relatively heavy pressing operation.

[0048] Furthermore, when the operation amount reaches the second stroke amount, since the metal inversion dome 130 performs an inversion operation, the operation load rapidly decreases. Therefore, the push switch 100 can present a click operation feeling to the operator at the timing when the push switch 100 switches to the second conduction state.

[0049] As described above, the push switch 100 according to one embodiment conducts the two contact portions 112A of the first fixed contact 112 by a pressing operation of the first stroke amount, and conducts the first fixed contact 112 and the second fixed contact 113 by a pressing operation of the second stroke amount. That is, since a common fixed contact (the first fixed contact 112) is conducted by the pressing operation of the first stroke amount and the pressing operation of the second stroke amount, a two-stage switch can be realized using a relatively small number of fixed contacts.

[0050] Although one embodiment of the present invention has been described in detail above, the present invention is not limited to these embodiments, and various modifications or changes are possible within the scope of the gist of the present invention described in the claims.

Description of Reference Numerals

[0051] 100 Push switch 110 Housing 110A Upper surface 110B Recess 110C Pedestal part 111 Claw part 112 First fixed contact 112A Contact part 112Aa Contact portion 113 Second fixed contact 114, 115 First fixed contact member 114A, 115A External connection terminal 116 Second fixed contact member 116A, 116B External connection terminal 120 Frame 120A Opening 121 Hook 121A Opening 130 Metal reversing dome (movable contact) 130A Opening 131 Dome part 132 Edge part 133 Leg part 140 Rubber stem 141 Operating part 141A Elastically deformable part 142 Base part 143 Central protrusion 143A Conductive part 144 First pressing part 145 Second pressing part

Claims

1. A housing having a recess, A rubber stem provided on the recess, having a central protrusion protruding downward, and having a conductive portion at the lower end of the central protrusion, A movable contact provided in the recess, having a domed shape capable of inverting operation, and having an opening through which the central protrusion can be inserted at the center, A first fixed contact provided on the inner bottom surface of the recess so as to face the conductive portion, A second fixed contact provided in contact with the movable contact around the first fixed contact on the inner bottom surface of the recess Comprising, The first fixed contact has a plurality of contact portions divided from each other, When a pressing operation of a first stroke amount of the rubber stem is performed, the conductive portion of the rubber stem passes through the opening of the movable contact and contacts each of the plurality of contact portions, so that the plurality of contact portions are electrically connected to each other through the conductive portion to form a first conduction state A push switch characterized by the above.

2. When a pressing operation of a second stroke amount larger than the first stroke amount of the rubber stem is performed, the rubber stem presses around the opening of the movable contact, and the movable contact performs an inversion operation and contacts each of the plurality of contact portions, so that the plurality of contact portions and the second fixed contact are electrically connected through the movable contact to form a second conduction state The push switch according to claim 1, characterized by the above.

3. Until the operation amount of the pressing operation reaches the first stroke amount, the operation load of the pressing operation gradually increases, From when the operation amount of the pressing operation reaches the first stroke amount until it reaches the second stroke amount, the operation load of the pressing operation rapidly increases, When the operation amount of the pressing operation reaches the second stroke amount, the operation load of the pressing operation rapidly decreases The push switch according to claim 2, characterized by the above.

4. The conductive portion is made of a conductive metal The push switch according to any one of claims 1 to 3, characterized by the above.

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