Push switch

Abstract

To reduce the operating load required for pressing operations and to suppress the operating noise of the movable contact members. [Solution] The push switch comprises a housing having a housing section and a fixed contact provided at the bottom of the housing section; a movable contact member disposed in the housing section, which can contact the fixed contact member by being pressed at the top and reversing; and a rubber stem made of a soft elastic material, disposed on the upper surface of the housing so as to cover the housing section, which presses the top of the movable contact member with the pressing section when a pressing operation is performed on the operating section. The rubber stem applies a load to the top of the movable contact member with the pressing section until the movable contact member returns from the reversed state to the initial state.

Description

Technical Field

[0006] , ,

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

Background Art

[0002] The following Patent Document 1 discloses a configuration related to a switch device, in which a movable contact member disposed in a housing portion of a case is pressed by a stem, and the movable contact member is inverted to bring the movable contact member into contact with a fixed contact portion.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the switch device of Patent Document 1, since the stem is in a horizontal state in the initial state, when the stem is pressed downward, it is necessary to elastically deform the horizontal portion of the stem so as to pull it downward. Since this elastic deformation becomes a resistance, a large operating load is required for the pressing operation.

[0005] In addition, in the switch device of Patent Document 1, there is a possibility that the inversion operation sound and the return operation sound of the movable contact member become large as the inversion operation and the return operation of the movable contact member are speeded up.

Means for Solving the Problems

[0006] A push switch according to one embodiment includes a housing having a housing portion and a fixed contact provided at the bottom of the housing portion, a movable contact member disposed in the housing portion and capable of contacting the fixed contact member by being pressed at the top and reversing, and a rubber stem made of a soft elastic material, disposed on the upper surface of the housing so as to cover the housing portion, and which presses the top of the movable contact member by a pressing portion when a pressing operation is performed on the operating portion, wherein the rubber stem applies a load to the top of the movable contact member by the pressing portion until the movable contact member returns from the reversed state to the initial state. [Effects of the Invention]

[0007] According to one embodiment of the push switch, the operating load required for pressing can be reduced, and the operating noise of the movable contact member can be suppressed. [Brief explanation of the drawing]

[0008] [Figure 1] External perspective view of a push switch according to one embodiment. [Figure 2] Exploded perspective view of a push switch according to one embodiment. [Figure 3] Cross-sectional view of a push switch according to one embodiment. [Figure 4] Cross-sectional view showing the operation of the rubber stem in a push switch according to one embodiment. [Modes for carrying out the invention]

[0009] An embodiment will be described below with reference to the drawings. For convenience, in the following description, the Z-axis direction in the drawings will be considered as the vertical direction, the Y-axis direction as the left-right direction, and the X-axis direction as the front-back direction. However, the positive Z-axis direction will be considered upward, the positive Y-axis direction as the rightward direction, and the positive X-axis direction as the forward direction. These indicate the relative positional relationships within the device and do not limit the installation or operation direction of the device. Any device with equivalent relative positional relationships within the device, even if installed or operated in a different direction, is included within the scope of the present invention.

[0010] (Overview of push switch 100) Figure 1 is an external perspective view of a push switch 100 according to one embodiment. As shown in Figure 1, the push switch 100 has a configuration in which a rubber stem 140 and a metal cover 120 are superimposed on the upper surface 110A of the housing 110, and the base 142 of the rubber stem 140 is covered by the metal cover 120.

[0011] Furthermore, as shown in Figure 1, a circular opening 120A is formed in the center of the metal cover 120. A cylindrical operating part 141, located in the center of the rubber stem 140, passes through the opening 120A. As a result, the operating part 141 of the rubber stem 140 protrudes upward (in the positive Z-axis direction) above the opening 120A.

[0012] The push switch 100 can be operated by pressing the operating part 141 of the rubber stem 140 downward (in the negative Z-axis direction), and this pressing operation can switch the switch from the off state to the on state.

[0013] (Configuration of push switch 100) Figure 2 is an exploded perspective view of a push switch 100 according to one embodiment. Figure 3 is a cross-sectional view of the push switch 100 according to one embodiment. As shown in Figures 2 and 3, the push switch 100 comprises a housing 110, a metal cover 120, a movable contact member 130, and a rubber stem 140.

[0014] The housing 110 is a container-like member having a thin rectangular parallelepiped shape in the vertical direction (Z-axis direction). When viewed from above, the housing 110 is generally square in shape. The housing 110 has a housing portion 110B that is recessed downward from the top surface 110A and is circular when viewed from above (positive Z-axis direction) in plan view. The movable contact member 130 is housed inside the housing portion 110B. For example, the housing 110 is formed by insert molding using a relatively hard insulating material (e.g., hard resin).

[0015] On each of the pair of left and right side surfaces of the housing 110, a protruding projection 111 is formed. When the metal cover 120 is attached to the upper surface 110A of the housing 110, the projection 111 is fitted into the opening 121A of the hook 121 of the metal cover 120, thereby hooking the hook 121 and fixing the metal cover 120 to the housing 110.

[0016] At the bottom of the accommodating portion 110B of the housing 110, a central fixed contact 112A and a pair of front and rear peripheral fixed contacts 113A are provided.

[0017] The central fixed contact 112A is provided at the central portion of the bottom of the accommodating portion 110B and is provided facing the back surface of the top (central portion) of the movable contact member 130.

[0018] The pair of front and rear peripheral fixed contacts 113A are provided on both the front and rear outer sides of the central fixed contact 112A at the bottom of the accommodating portion 110B. On each of the pair of front and rear peripheral fixed contacts 113A, each of the pair of arc-shaped edge portions of the movable contact member 130 is placed.

[0019] Note that the central fixed contact member 112 and the peripheral fixed contact member 113 are embedded in the bottom of the housing 110 by insert molding. Both the central fixed contact member 112 and the peripheral fixed contact member 113 are formed using a conductive plate material (for example, a metal plate).

[0020] The central fixed contact 112A is integrally formed on the central fixed contact member 112. Further, the central fixed contact member 112 has a pair of front and rear external connection terminals 112B that protrude from the side surfaces on the front side (positive X-axis side) and the rear side (negative X-axis side) of the housing 110.

[0021] In addition, a pair of front and rear peripheral fixed contact members 113 are integrally formed with the peripheral fixed contact portion member 113. Further, the peripheral fixed contact member 113 has a pair of front and rear external connection terminals 113B that protrude from the side surfaces on the front side (positive X-axis side) and the rear side (negative X-axis side) of the housing 110.

[0022] The movable contact member 130 is provided in the housing portion 110B of the housing 110. The metal inverted dome 131 is a dome-shaped (convex upward) member made of a thin metal plate that can perform an inversion operation. The metal inverted dome 131 has an oval shape with the longitudinal direction in the front-rear direction (X-axis direction) in a plan view from above (positive Z-axis direction).

[0023] The movable contact member 130 is placed on each of a pair of front and rear peripheral fixed contacts 113A provided at the bottom of the housing portion 110B of the housing 110, with each of the pair of front and rear arc-shaped edges. As a result, the movable contact member 130 is stably supported by the pair of front and rear arc-shaped edges and is electrically connected to each of the pair of front and rear peripheral fixed contacts 113A.

[0024] The movable contact member 130 is a so-called "inverting spring". When the top (central part) is pressed from above and a predetermined pressing load is exceeded, the top (central part) rapidly elastically deforms (inverts) into a concave shape. As a result, the portion on the back side of the top (central part) of the movable contact member 130 comes into contact with the central fixed contact 112A provided at the center of the bottom of the housing portion 110B of the housing 110. As a result, each of the pair of front and rear peripheral fixed contacts 113A and the central fixed contact 112A are electrically connected via the movable contact member 130. Note that when the pressing of the top (central part) is released in the inverted state, the movable contact member 130 returns to its convex initial state by its own elastic force.

[0025] The rubber stem 140 is a component that is pressed downward (in the negative Z-axis direction) by the operator. The rubber stem 140 is mounted on top of the upper surface 110A of the housing 110. As a result, the rubber stem 140 closes the housing portion 110B of the housing 110. Furthermore, the rubber stem 140 is sandwiched between the metal cover 120 and the upper surface 110A of the housing 110, as the metal cover 120 is mounted on top of the base portion 142 (described later) on the positive Z-axis side.

[0026] The rubber stem 140 is formed using a soft elastic material (for example, silicone rubber). The rubber stem 140 has an operating portion 141, a base portion 142, a pressing portion 143, and an elastically deformable portion 144.

[0027] The base portion 142 is a horizontal, flat plate-like section provided around the operating portion 141. The base portion 142 has a roughly square shape when viewed from above (in the positive Z-axis direction). The base portion 142 has a circular opening 142A formed in the center.

[0028] The operating part 141 is a cylindrical portion located in the center of the rubber stem 140 (the center inside the opening 142A of the base 142). The operating part 141 penetrates the opening 120A of the metal cover 120 and protrudes above the opening 120A of the metal cover 120 (in the positive Z-axis direction), so that it is the part that is pressed by the operator.

[0029] The pressing portion 143 is a convex portion that protrudes downward from the center of the lower surface of the operating portion 141. As shown in Figure 3, when the operating portion 141 is not being pressed, the lower surface of the pressing portion 143 is in contact with the top (center) of the movable contact member 130. When the operating portion 141 is pressed by the operator, the pressing portion 143 moves downward (in the negative Z-axis direction) together with the operating portion 141, thereby pressing the top (center) of the movable contact member 130 with the lower surface of the pressing portion 143.

[0030] The elastically deformable portion 144 is positioned inside the opening 142A of the base portion 142 and is a membrane-like portion that connects the inner circumference of the opening 142A of the base portion 142 to the outer circumference of the operating portion 141. When viewed from above (positive Z-axis direction) in plan view, the elastically deformable portion 144 has an annular shape surrounding the operating portion 141. The elastically deformable portion 144 supports the operating portion 141 and, by elastically deforming, can move the operating portion 141 in the vertical direction (Z-axis direction).

[0031] The metal cover 120 is a flat, horizontal metal plate. When viewed from above, the metal cover 120 has a square shape. The metal cover 120 is placed on top of the upper surface of the base 142 of the rubber stem 140. The metal cover 120 is then fixed to the housing 110 while pressing down on the base 142 of the rubber stem 140.

[0032] For example, the metal cover 120 is formed by processing a metal plate using a pressing or other processing method. In a plan view from above (positive Z-axis direction), a circular opening 120A is formed in the center of the metal cover 120 to allow the operating portion 141 of the rubber stem 140 to protrude upward (positive Z-axis direction).

[0033] Furthermore, each of the pair of left and right sides on the outer periphery of the metal cover 120 is provided with a hook 121 that hangs downward. The hook 121 has an opening 121A into which a projection 111 provided on the side of the housing 110 is fitted. In this way, the hook 121 is hooked onto the lower surface of the projection 111, and the metal cover 120 can be fixed to the housing 110.

[0034] (Operation of push switch 100) In one embodiment of the push switch 100, when the operator is not pressing the operating portion 141 of the rubber stem 140, the operating portion 141 of the rubber stem 140 is in its highest initial position, and the movable contact member 130 is in an initial convex position upward. At this time, each of the front and rear pair of arc-shaped edges of the movable contact member 130 is in contact with each of the front and rear pair of peripheral fixed contacts 113A, but not with the central fixed contact 112A. Therefore, in one embodiment of the push switch 100, when the operator is not pressing the operating portion 141 of the rubber stem 140, the switch is in the off state.

[0035] In one embodiment of the push switch 100, when an operator presses the operating portion 141 of the rubber stem 140, the operating portion 141 and the pressing portion 143 of the rubber stem 140 move downward, and the lower surface of the pressing portion 143 of the rubber stem 140 pushes down the top (center) of the movable contact member 130. As a result, the movable contact member 130 elastically deforms into a concave shape (reversal movement), and the back side of the top (center) of the movable contact member 130 comes into contact with the central fixed contact 112A. Consequently, in one embodiment of the push switch 100, the front and rear pair of peripheral fixed contacts 113A and the central fixed contact 112A become electrically connected to each other via the movable contact member 130, thereby turning the switch ON.

[0036] Subsequently, in one embodiment of the push switch 100, when the operator releases the pressing operation on the operating portion 141 of the rubber stem 140, the movable contact member 130 returns from its inverted state to its convex initial state by its own elastic force. At this time, the movable contact member 130 pushes the operating portion 141 and the pressing portion 143 of the rubber stem 140 upward, thereby returning the operating portion 141 and the pressing portion 143 of the rubber stem 140 to their initial positions.

[0037] (Load-bearing function of the Rubber Stem 140) Figure 4 is a cross-sectional view showing the operation of the rubber stem 140 in a push switch 100 according to one embodiment. However, in Figure 4, the hatching of the cross-section of the rubber stem 140 is omitted.

[0038] As shown by the dotted line in Figure 4, in the unloaded state (i.e., when the operating part 141 and pressing part 143 are not being pushed up by the movable contact member 130), the rubber stem 140 is in a state where the operating part 141 and pressing part 143 have moved downward (in the negative Z-axis direction) to a height position where the lower surface of the pressing part 143 contacts the central fixed contact 112A. At this time, the elastically deformable part 144 becomes a downward slope from the base 142 side (outer circumference side) to the operating part 141 side (inner circumference side). Similarly, even when the movable contact member 130 is reversed and in contact with the central fixed contact 112A, and a slight load is applied, the elastically deformable part 144 of the rubber stem 140 becomes a downward slope from the base 142 side (outer circumference side) to the operating part 141 side (inner circumference side).

[0039] In particular, in this embodiment, the elastically deformable portion 144 has an annular shape when viewed from above, and in an unloaded state, the entire circumference of the annular shape becomes a downward slope, thus having a mortar-like shape. Similarly, even when the movable contact member 130 of the rubber stem 140 is reversed and in contact with the central fixed contact 112A, and a slight load is applied, the elastically deformable portion 144 has a mortar-like shape.

[0040] Then, as shown by the solid line in Figure 4, when the movable contact member 130 is positioned in the housing portion 110B of the housing 110, the rubber stem 140 is pushed upward (in the positive Z-axis direction) by the top of the movable contact member 130, causing the operating portion 141 and the pressing portion 143 to be pushed upward. At this time, the elastically deformable portion 144 becomes an upward slope from the base portion 142 side (outer circumference side) to the operating portion 141 side (inner circumference side) due to elastic deformation, and the intermediate portion between the base portion 142 side (outer circumference side) and the operating portion 141 side (inner circumference side) becomes sagging downward. As a result, the elastically deformable portion 144 generates a downward (negative Z-axis direction) reaction force (i.e., a force that tries to return to its original shape).

[0041] The rubber stem 140, through the reaction force of the elastically deformable portion 144, biases the operating portion 141 and the pressing portion 143 downward (in the negative Z-axis direction), allowing a load to be constantly applied to the top of the movable contact member 130 by the lower surface of the pressing portion 143.

[0042] Therefore, as shown by the solid line in Figure 4, when the operator is not pressing the operating part 141 (i.e., when it is in its initial position), the rubber stem 140 is in a state where the lower surface of the pressing part 143 is applying preload to the top of the movable contact member 130 due to the reaction force of the elastic deformation part 144. This preload is generated by the weight of the center of the rubber stem 140 and the force of the elastic deformation part 144 trying to return to its original shape.

[0043] Furthermore, while the movable contact member 130 is reversing from its initial state (convex) to its reversed state (concave) due to the reversal movement of the rubber stem 140, the lower surface of the pressing portion 143 applies a load to the top of the movable contact member 130 due to the reaction force of the elastic deformation portion 144, while the operating portion 141 and the pressing portion 143 move downward (negative Z-axis direction) following the top of the movable contact member 130.

[0044] As a result, in one embodiment of the push switch 100, when the operating part 141 and the pressing part 143 move downward (negative Z-axis direction) due to the pressing operation, the elastic deformation of the elastic deformation part 144 does not act as resistance, thus reducing the operating load required for the pressing operation.

[0045] Furthermore, in this embodiment, the push switch 100 can always keep the pressing portion 143 of the rubber stem 140 in contact with the top of the movable contact member 130 when the movable contact member 130 is in a reversing motion. This absorbs vibrations of the movable contact member 130, thereby suppressing the noise produced when the movable contact member 130 is in a reversing motion.

[0046] Furthermore, while the movable contact member 130 returns from the inverted state (concave) to the initial state (convex) due to the return operation, the rubber stem 140 applies a load to the top of the movable contact member 130 by the reaction force of the elastic deformation portion 144, with the lower surface of the pressing portion 143 acting as a load. At the same time, the operating portion 141 and the pressing portion 143 can move upward (in the positive Z-axis direction) following the top of the movable contact member 130.

[0047] As a result, the push switch 100 according to one embodiment can reduce the return operation speed of the movable contact member 130, thereby suppressing the return operation noise of the movable contact member 130.

[0048] Furthermore, in this embodiment, the push switch 100 can always keep the pressing portion 143 of the rubber stem 140 in contact with the top of the movable contact member 130 when the movable contact member 130 returns to its original position. This absorbs vibrations of the movable contact member 130, thereby suppressing the noise of the movable contact member 130 during its return operation.

[0049] Furthermore, as a result, the push switch 100 according to one embodiment is less affected by the tension force of the elastically deformable part 144, and thus the click rate can be increased.

[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 as described in the claims. [Explanation of Symbols]

[0051] 100 push switches 110 Housing 110A top 110B Storage Unit 111 Protrusion 112 Central fixed contact member 112A central fixed contact 112B External connection terminal 113 Peripheral fixed contact member 113A Peripheral fixed contact 113B External connection terminal 120 Metal cover 120A opening 121 Hook 121A opening 130 Movable contact member 140 Rubber Stem 141 Operation section 142 Base 143 Pressing part 144 Elastic deformation part

Claims

1. A housing having a storage section and a fixed contact provided at the bottom of the storage section, A movable contact member is provided in the housing section, and is capable of contacting the fixed contact by being pressed at its top and reversing. A rubber stem is formed of a soft elastic material, positioned on the upper surface of the housing so as to cover the housing portion, and when a pressing operation is performed on the operating portion, the pressing portion presses the top of the movable contact member. Equipped with, The aforementioned rubber stem is, The pressing portion applies a load to the top of the movable contact member while the movable contact member is returning from the reversed state to the initial state. A push switch characterized by the following features.

2. The aforementioned rubber stem is, When the aforementioned pressing operation is not performed, the pressing part applies prepressure to the top of the movable contact member. The push switch according to feature 1.

3. The aforementioned rubber stem is, The pressing portion applies a load to the top of the movable contact member while the movable contact member is moving from the initial state to the reversed state. The push switch according to feature 1.

4. The aforementioned rubber stem is, The housing has an elastically deformable portion that connects the base portion, which is placed on the upper surface of the housing, to the operating portion, and when the movable contact member is inverted and in contact with the fixed contact, the elastically deformable portion becomes a downward slope from the base portion side to the operating portion side. The push switch according to feature 1.

5. The elastically deformable portion has a mortar-like shape when the movable contact member is inverted and in contact with the fixed contact. The push switch according to feature 4.

6. The housing includes a metal cover that covers the base of the rubber stem and presses the base of the rubber stem against the upper surface of the housing. The push switch according to feature 4.

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