Push switch

Abstract

To provide a push switch using a dome-like movable contact point which can maintain a waterproof function even if an impact is applied.SOLUTION: A push switch 1 contains: a case 2 having a housing part 23 and a sealing groove 25; a pair of contact points 3 and 4 separately provided in the housing part 23 each other; a movable contact point 5b arranged on an upper side of the pair of contact points 3 and 4 in the housing part 23; a base part 71 arranged on the case 2; a cap 7 having a sealing projection part 76 that is projected from a peripheral edge part of the base part 71 and seals the sealing groove 25 of the case 2 in a fluid-tight; a cover 8 attached to the case 2 from an upper direction so as to hold the cap 7 on the case 2. The sealing projection part 76 of the cap 7 is compressed and deformed in the sealing groove 25 of the case 2. Thus, the sealing groove 25 of the case 2 is sealed in the fluid-tight.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention generally relates to a push switch, and more particularly to a push switch that operates with a clicking sensation when pressed. [Background technology]

[0002] Push switches with dome-shaped movable contacts are widely used as operation buttons for various electronic devices. These push switches can be made smaller and thinner, and provide users with a pleasant clicking sensation (pressure sensation) when the operation button is activated by pressing it.

[0003] For example, Patent Document 1 discloses a push switch 500 as shown in Figures 1 and 2. Figure 1 is an exploded perspective view of the push switch 500, and Figure 2 is a perspective view of the push switch 500. As shown in Figures 1 and 2, the push switch 500 comprises a case 510 including a substantially rectangular bottom plate 511, four wall portions 512 extending upward from each side of the bottom plate 511, a storage portion 513 defined by the bottom plate 511 and the four wall portions 512, and engaging protrusions 514 formed on each of a pair of opposing wall portions 512 (a pair of wall portions extending in the Y direction in the figure); a center contact 520 and an outer contact 530 provided spaced apart from each other on the bottom plate 511 of the case 510; and a center contact 520 and an outer contact 530 provided in the storage portion 513 of the case 510. 0 and outer contacts 530, a flat base portion 551 formed from an elastic material and placed on the upper end surfaces of four wall portions 512 of case 510, a protrusion 552 formed approximately in the center of base portion 551 for pressing dome-shaped movable contact 540 downward, and a cap 550 that covers storage portion 513 of case 510 from above, and a metal cover 560 that holds cap 550 on case 510 by pressing base portion 551 of cap 550 from above.

[0004] The cover 560 includes a top plate 561 having a substantially rectangular planar shape, a circular opening 562 formed substantially in the center of the top plate 561, and a pair of extensions 563 extending downward from a pair of opposing sides of the top plate 561 (a pair of sides extending in the Y direction in the figure). Each of the pair of extensions 563 includes a pair of legs 5631 extending downward from the side of the top plate 561 and a bridge portion 5632 connecting the lower ends of the pair of legs 5631 to each other. The bridge portion 5632 slopes outward from the lower ends of the pair of legs 5631. Each of the engagement protrusions 514 of the case 510 includes an inclined surface 5141 whose height gradually increases from top to bottom and a flat portion 5142 extending linearly downward from the top of the inclined surface 5141.

[0005] With dome-shaped movable contact 540 disposed within storage portion 513 of case 510 and base portion 551 of cap 550 disposed on the upper end surfaces of multiple wall portions 512 of case 510, cover 560 is pressed against case 510 from above (+Z direction) to attach cover 560 to case 510, thereby assembling push switch 500. When attaching cover 560 to case 510 from above, bridge portions 5632 of a pair of extension portions 563 of cover 560 slide on inclined surfaces 5141 of engaging protrusions 514 of case 510. This causes the pair of extension portions 563 of cover 560 to open outward, making it possible to push cover 560 downward (-Z direction). Thereafter, when the bridging portions 5632 of the pair of extension portions 563 of the cover 560 each pass over the flat portions 5142 of the pair of engaging protrusions 514 of the case 510, the lower end surfaces of the flat portions 5142 of the engaging protrusions 514 of the case 510 engage with the upper end surfaces of the bridging portions 5632 of the pair of extension portions 563 of the cover 560, the cover 560 is locked to the case 510, and the push switch 500 is assembled.

[0006] As shown in FIG. 2 , when the push switch 500 is assembled, the protrusion 552 of the cap 550 is inserted through the opening 562 of the cover 560 and protrudes upward from the top plate 561 of the cover 560. Furthermore, the cover 560 is locked to the case 510, and the base 551 of the cap 550 is held in a compressed state between the upper end surface of the wall 512 of the case 510 and the top plate 561 of the cover 560. Therefore, the space between the case 510 and the cover 560 is liquid-tightly sealed by the base 551 of the cap 550, preventing water from entering the storage compartment 513 of the case 510. This configuration enables the push switch 500 to achieve waterproof performance.

[0007] Because such a push switch 500 is waterproof, it is often used in handheld electronic devices such as smartphones and game console controllers. However, if a strong impact is applied to the electronic device, such as when a user drops the electronic device on the ground, the cap 550 held between the case 510 and cover 560 of the push switch 500 may become misaligned, tilted, or deformed, creating a gap between the case 510 of the push switch 500 and the base portion 551 of the cap 550. Similarly, if a high load or heavy load is applied to the push switch 500, the cap 550 held between the case 510 and cover 560 of the push switch 500 may become misaligned, tilted, or deformed, creating a gap between the case 510 of the push switch 500 and the base portion 551 of the cap 550.

[0008] In these cases, water can seep into housing portion 513 of case 510 through a gap that forms between case 510 of push switch 500 and base portion 551 of cap 550. Water that seeps into housing portion 513 of case 510 can corrode center contact 520 and outer contact 530, impairing the functionality of push switch 500. For this reason, there has been a strong need to maintain the waterproof performance of push switches that use dome-shaped movable contacts, even when subjected to impacts, high loads, or heavy loads. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-113652 Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in consideration of the above-mentioned conventional problems, and its object is to provide a push switch that uses a dome-shaped movable contact and that can maintain its waterproof function even when impacts, high loads, and heavy loads are applied. [Means for solving the problem]

[0011] Such objectives are as follows: (1) ~(3) This is achieved by the present invention as defined in (1) A case including a storage section defined by a bottom plate and a plurality of wall portions extending upward from the bottom plate, and a sealing groove formed on an upper end surface of the plurality of wall portions; a pair of contacts spaced apart from each other and provided on the bottom plate within the storage section; a movable contact disposed above the pair of contacts in the storage section, the movable contact being displaceable between a first position where the pair of contacts are in a non-conductive state and a second position where the pair of contacts are in a conductive state; a cap that covers the storage section of the case from above, the cap including: a flat base section that is disposed on the upper end surfaces of the plurality of wall sections of the case; a protruding section that protrudes upward from the base section; and a sealing protrusion that protrudes downward from a peripheral edge of the base section and that liquid-tightly seals the sealing groove of the case; a cover including a top plate and an opening formed in the top plate to allow the protruding portion of the cap to pass through, the cover being attached to the case from above to hold the cap on the case; When the cap is held on the case by the cover, the sealing protrusion of the cap is compressed and deformed in the sealing groove of the case, thereby sealing the sealing groove of the case liquid-tightly; the case further includes a pair of cover locking portions formed spaced apart from each other on each of a pair of opposing wall portions among the plurality of wall portions, the cover further includes a pair of engagement extensions extending downward from a pair of opposing sides of the top plate, Each of the pair of engaging extension portions includes a pair of legs extending downward from the side of the top plate while being spaced apart from each other, and a locking portion connecting lower tip ends of the pair of legs, outer side surfaces of the pair of legs of the engagement extension portion extending from the side of the top plate engage with inner side surfaces of the pair of cover locking portions formed on the pair of opposing wall portions of the case, The upper end surfaces of the locking portions of the engagement extensions extending from the sides of the top plate are engaged with the lower end surfaces of the pair of cover locking portions formed on the wall portions of the case. A push switch characterized by: (2) a case including a storage section defined by a bottom plate and a plurality of wall portions extending upward from the bottom plate, and a sealing groove formed on an upper end surface of the plurality of wall portions; a pair of contacts spaced apart from each other and provided on the bottom plate within the storage section; a movable contact disposed above the pair of contacts in the storage section, the movable contact being displaceable between a first position where the pair of contacts are in a non-conductive state and a second position where the pair of contacts are in a conductive state; a cap that covers the storage section of the case from above, the cap including: a flat base section that is disposed on the upper end surfaces of the plurality of wall sections of the case; a protruding section that protrudes upward from the base section; and a sealing protrusion that protrudes downward from a peripheral edge of the base section and that liquid-tightly seals the sealing groove of the case; a cover including a top plate and an opening formed in the top plate to allow the protruding portion of the cap to pass through, the cover being attached to the case from above to hold the cap on the case; When the cap is held on the case by the cover, the sealing protrusion of the cap is compressed and deformed in the sealing groove of the case, thereby sealing the sealing groove of the case liquid-tightly; The cap further includes a pair of outward extending portions extending outward from a pair of opposing sides of the base portion, the case further includes a pair of notches formed on the upper end surfaces of the wall portions, A push switch, characterized in that the pair of outward extending portions of the cap engage with the pair of notched portions of the case. (3) a case including a storage section defined by a bottom plate and a plurality of wall portions extending upward from the bottom plate, and a sealing groove formed on an upper end surface of the plurality of wall portions; a pair of contacts spaced apart from each other and provided on the bottom plate within the storage section; a movable contact disposed above the pair of contacts in the storage section, the movable contact being displaceable between a first position where the pair of contacts are in a non-conductive state and a second position where the pair of contacts are in a conductive state; a cap that covers the storage section of the case from above, the cap including: a flat base section that is disposed on the upper end surfaces of the plurality of wall sections of the case; a protruding section that protrudes upward from the base section; and a sealing protrusion that protrudes downward from a peripheral edge of the base section and that liquid-tightly seals the sealing groove of the case; a cover including a top plate and an opening formed in the top plate to allow the protruding portion of the cap to pass through, the cover being attached to the case from above to hold the cap on the case; a frame including a bottom plate and attached to the case from below; When the cap is held on the case by the cover, the sealing protrusion of the cap is compressed and deformed in the sealing groove of the case, thereby sealing the sealing groove of the case liquid-tightly; the case is held between the cover and the frame, The top plate of the cover has a substantially rectangular planar shape, the cover further includes a pair of welding pieces extending downward from each of a pair of opposing sides of the top plate; the bottom plate of the frame has a substantially rectangular planar shape, the frame further includes a pair of welding pieces extending upward from a pair of opposing sides of the bottom plate, A push switch characterized in that the pair of welding pieces of the cover are welded to the pair of welding pieces of the frame, respectively, thereby holding the case between the cover and the frame which are welded to each other. [Effects of the Invention]

[0012] In the push switch of the present invention, the sealing protrusion extending downward from the peripheral edge of the base of the cap is compressed and deformed within the sealing groove of the case, thereby sealing the sealing groove of the case liquid-tightly. Therefore, even if a strong impact or high load is applied to the push switch, no gap will form between the cap and the case, and the waterproof function of the push switch can be maintained.

[0013] Furthermore, in the push switch of the present invention, the waterproof function is achieved by compressing and deforming the sealing protrusion of the cap, which is made of an elastic material, within the sealing groove of the case. Therefore, there is no need to use additional parts to achieve the waterproof function, and the number of parts in the push switch can be reduced. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is an exploded perspective view of a conventional push switch. [Figure 2] FIG. 2 is a perspective view of the conventional push switch shown in FIG. [Figure 3] 1 is a perspective view of a push switch according to the present invention; [Figure 4] 4 is a perspective view of the push switch shown in FIG. 3 as viewed from a different angle. [Figure 5] FIG. 4 is an exploded perspective view of the push switch shown in FIG. 3. [Figure 6] 6 is a perspective view of the case, the center contact, and the outer contact of the push switch shown in FIG. 5, viewed from a different angle. [Figure 7] 6 is a perspective view of the case, the central contact, and the outer contact of the push switch shown in FIG. 5, viewed from yet another angle. [Figure 8]FIG. 8 is a perspective view of the center and outer contacts shown in FIGS. 6 and 7. [Figure 9] 6 is a perspective view of the pressing member shown in FIG. 5, seen from a different angle. [Figure 10] FIG. 6 is a perspective view of the cap shown in FIG. 5, seen from a different angle. [Figure 11] FIG. 6 is a perspective view of the cover shown in FIG. 5, seen from a different angle. [Figure 12] FIG. 6 is a perspective view of the frame shown in FIG. 5, seen from a different angle. [Figure 13] 10 is a perspective view showing a state in which a first movable contact, a second movable contact, a pressing member, and a cap are housed in a housing portion of a case. FIG. [Figure 14] 4 is a longitudinal cross-sectional view of the push switch taken along line AA in FIG. 3 in a natural state in which no pressing force is applied to the push switch. [Figure 15] 4 is a longitudinal cross-sectional view of the push switch taken along line AA in FIG. 3 in a pressed state where a pressing force exceeding the actuation force of the push switch is applied to the push switch. [Figure 16] 1 is a plan view of a push switch according to the present invention; [Figure 17] FIG. 2 is a bottom view of the push switch according to the present invention. [Figure 18] FIG. 1 is a front view of a push switch according to the present invention. [Figure 19] FIG. 2 is a rear view of the push switch according to the present invention. [Figure 20] FIG. 2 is a left side view of the push switch according to the present invention. [Figure 21] FIG. 2 is a right side view of the push switch according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] The push switch of the present invention will be described below based on preferred embodiments shown in the accompanying drawings. Note that the drawings referred to below are schematic diagrams prepared for the purpose of explaining the present invention. The dimensions (length, width, thickness, etc.) of each component shown in the drawings do not necessarily reflect the actual dimensions. Furthermore, the same reference numerals are used for identical or corresponding components in each drawing. In the following description, the positive direction of the Z axis in each drawing may be referred to as "upward," and the negative direction of the Z axis may be referred to as "downward."

[0016] The push switch of the present invention will be described in detail below with reference to FIGS. 3 to 15. FIG. 3 is a perspective view of the push switch of the present invention. FIG. 4 is a perspective view of the push switch shown in FIG. 3, viewed from a different angle. FIG. 5 is an exploded perspective view of the push switch shown in FIG. 3. FIG. 6 is a perspective view of the case, center contact, and outer contact of the push switch shown in FIG. 5, viewed from a different angle. FIG. 7 is a perspective view of the case, center contact, and outer contact of the push switch shown in FIG. 5, viewed from yet another angle. FIG. 8 is a perspective view of the center contact and outer contacts shown in FIGS. 6 and 7. FIG. 9 is a perspective view of the pressing member shown in FIG. 5, viewed from a different angle. FIG. 10 is a perspective view of the cap shown in FIG. 5, viewed from a different angle. FIG. 11 is a perspective view of the cover shown in FIG. 5, viewed from a different angle. FIG. 12 is a perspective view of the frame shown in FIG. 5, viewed from a different angle. FIG. 13 is a perspective view showing the first movable contact, the second movable contact, the pressing member, and the cap housed in the housing of the case. Fig. 14 is a vertical cross-sectional view of the push switch taken along line AA in Fig. 3 in a natural state where no pressing force is applied to the push switch. Fig. 15 is a vertical cross-sectional view of the push switch taken along line AA in Fig. 3 in a pressed state where a pressing force exceeding the actuating force of the push switch is applied to the push switch.

[0017] The push switch 1 according to the embodiment of the present invention shown in FIGS. 3 and 4 is a switch that turns on when a user applies a pressing force that exceeds the actuation force of the push switch 1, and turns off when the pressing force applied by the user is released. The push switch 1 also has a waterproof function that can prevent water from entering the push switch 1. Therefore, the push switch 1 is typically used in electronic devices that may be exposed to water. For example, the push switch 1 can be used as a push switch for handheld electronic devices such as smartphones and game console controllers.

[0018] 3 and 4, the push switch 1 has a shape in which a protrusion 72 that is pressed by the user protrudes upward from a low-profile rectangular parallelepiped case 2. As shown in Fig. 5, the push switch 1 includes the case 2, a central contact 3, an outer contact 4, an auxiliary spring 5a, a movable contact 5b, a pressing member 6, a cap 7, a cover 8, and a frame 9.

[0019] The case 2 is a box-shaped member made of insulating resin and opens upward. The structure of the case 2 will be described in detail below with reference to FIGS. 6 and 7. FIGS. 6 and 7 show the case 2 holding the central contact 3 and the outer contacts 4. As shown in FIGS. 6 and 7, the case 2 includes a bottom plate 21, a pair of long walls 22L and a pair of short walls 22S extending upward from the outer periphery of the bottom plate 21, a storage section 23 defined by the bottom plate 21 and the pair of long walls 22L and the pair of short walls 22S extending upward from the bottom plate 21, and a receiving recess 24 and a sealing groove 25 formed on upper end surfaces 221 of the long walls 22L and the short walls 22S. The sealing groove 25 is also formed on the bottom surface of the receiving recess 24.

[0020] The case 2 holds the center contact 3 and the outer contacts 4 inside while insulating them from each other. The bottom plate 21 is a plate-like member having a substantially quadrangular (more specifically, substantially rectangular) planar shape and functions as the substrate of the push switch 1. As shown in FIG. 7 , the bottom plate 21 has a recess 211 formed on its lower surface, a protrusion 212 protruding downward from the recess 211, and a pair of horizontal extensions 213 formed to sandwich the protrusion 212. The recess 211 is formed on the lower surface of the bottom plate 21 to accommodate the bottom plate 91 of the frame 9. The depth of the recess 211 is substantially equal to the thickness of the bottom plate 91 of the frame 9. The protrusion 212 is a substantially rectangular protrusion protruding downward from approximately the center of the recess 211. As shown in FIG. 4 , when the frame 9 is attached to the case 2, the protrusions 212 pass through openings 911 formed in the bottom plate 91 of the frame 9, preventing the frame 9 from swinging in the planar direction relative to the case 2. The pair of horizontal extensions 213 extend linearly inward from each of the two wall portions of the recess 211 in the Y-axis direction. When the frame 9 is attached to the case 2, the pair of horizontal extensions 213 engage with a pair of notches 912 formed on a pair of short sides of the bottom plate 91 of the frame 9, preventing the frame 9 from swinging in the X-axis direction relative to the case 2. It should be noted that the term "approximately quadrangle" used in this specification refers not only to a square but also to a rectangle, a quadrangle with rounded corners, a quadrangle with part of it cut out, and the like.

[0021] Returning to FIG. 6 , the pair of long wall portions 22L extend upward from the long sides of the bottom plate 21 and are integrally formed with the bottom plate 21. Similarly, the pair of short wall portions 22S extend upward from the short sides of the bottom plate 21 and are integrally formed with the bottom plate 21. The storage portion 23 is a recess that opens upward and is defined by the upper surface of the bottom plate 21, the inner surfaces of the long wall portions 22L, and the inner surfaces of the short wall portions 22S. In the illustrated embodiment, the inner surfaces of the storage portion 23 form a substantially quadrangular (more specifically, substantially rectangular) planar shape. Each component of the push switch 1 is stored in the storage portion 23. In this way, the case 2 functions as a housing that stores each component of the push switch 1 in the storage portion 23. The case 2 also holds the center contact 3 and the outer contacts 4 in a mutually insulated state. The case 2 is obtained by placing the central contact 3 and the outer contacts 4 in a mold having an inner shape corresponding to the shape of the case 2, injecting insulating resin into the mold, and allowing it to harden.

[0022] As shown in Figures 6 and 7, each of the pair of long wall portions 22L includes a central protrusion 222L formed on its outer surface, a pair of frame locking portions 223L formed on both sides of the central protrusion 222L, a pair of receiving grooves 224L formed on the outside of the pair of frame locking portions 223L, and a notch portion 225L formed in its upper end surface 221.

[0023] The central protrusion 222L is a rectangular portion formed on approximately the center of the outer surface of the long wall portion 22L so as to protrude outward. The upper end surface of the central protrusion 222L is a flat surface that is continuous with the notch 225L formed in the upper end surface 221 of the long wall portion 22L. As shown in FIG. 3 , when the cover 8 is attached to the case 2, the central protrusion 222L engages with an engagement recess 851 formed in the lower end of the downward extension portion 85 that extends downward from approximately the center of the long side of the top plate 81 of the cover 8, thereby preventing the cover 8 from swinging in the Y-axis direction on the case 2.

[0024] Returning to FIG. 7, the pair of frame locking portions 223L are tapered portions formed on the outer surfaces of the long wall portion 22L and extending in the Z-axis direction. The pair of frame locking portions 223L are formed on the outer surfaces of the long wall portion 22L so as to sandwich the central protrusion 222L in the Y-axis direction while being spaced apart from the central protrusion 222L. Each of the pair of frame locking portions 223L has a guide slope 2231L whose height gradually increases from below to above, and a flat portion 2232L that extends linearly upward from the top of the guide slope 2231L. The guide slope 2231L has the function of guiding the locking portion 922 (see FIG. 3) of the engagement portion 92 that extends upward from the long side of the bottom plate 91 of the frame 9 when the frame 9 is attached to the case 2 from below. When attaching the frame 9 to the case 2 from below, the locking portions 922 of the engagement portions 92 of the frame 9 slide on the guide slopes 2231L, causing the engagement portions 92 of the frame 9 to open outward, thereby guiding the attachment of the frame 9 to the case 2. The flat portions 2232L engage with the locking portions 922 of the engagement portions 92 of the frame 9 when the frame 9 is attached to the case 2, and have the function of preventing the frame 9 from coming off the case 2. When attaching the frame 9 to the case 2 from below, once the locking portions 922 of the engagement portions 92 of the frame 9 climb over the flat portions 2232L, the engagement portions 92 of the frame 9 elastically return to their original state inward, and the upper end surface of the flat portions 2232L engages with the lower end surface of the locking portions 922 of the engagement portions 92 of the frame 9, thereby locking the frame 9 to the case 2. At this time, the straight portion 921 of the engagement portion 92 of the frame 9 is positioned within the space between the central protrusion 222L and the frame locking portion 223L.

[0025] Returning to FIG. 7, each of the pair of receiving grooves 224L is a space defined between the frame locking portion 223L and the short wall portion 22S. The receiving groove 224L includes a first receiving groove 2241L defined by the frame locking portion 223L, the short wall portion 22S, and the outer surface of the long wall portion 22L, and a rectangular second receiving groove 2242L formed on the bottom surface of the first receiving groove 2241L (the outer surface of the long wall portion 22L) and extending in the Z-axis direction. The first receiving groove 2241L is formed to accommodate the welding piece 84 of the cover 8 (see FIG. 11). The second receiving groove 2242L is formed to accommodate the welding piece 93 of the frame 9 (see FIG. 12).

[0026] 4, when the frame 9 is attached to the case 2, a pair of welding pieces 93 extending upward from each long side of the bottom plate 91 of the frame 9 are positioned in the second receiving grooves 2242L of the pair of receiving grooves 224L, respectively. Furthermore, when the cover 8 is attached to the case 2, a pair of welding pieces 84 extending downward from each long side of the top plate 81 of the cover 8 are positioned in the first receiving grooves 2241L of the pair of receiving grooves 224L, respectively. The depth (length in the X-axis direction) of the second receiving groove 2242L is approximately equal to the thickness of the welding pieces 93 of the frame 9, so the bottom surface of the first receiving groove 2241L and the outer surface (welding surface) 931 (see FIG. 12) of the welding pieces 93 of the frame 9 are positioned on the same plane. Also, the inner surface (welding surface) 841 (see FIG. 11) of the welding piece 84 of the cover 8 positioned in the first receiving groove 2241L contacts the bottom surface of the first receiving groove 2241L and the outer surface (welding surface) 931 of the welding piece 93 of the frame 9.

[0027] 6, the cutout portion 225L is a portion formed by cutting out approximately the center in the Y-axis direction of the upper end surface 221 of the long wall portion 22L. When the base portion 71 of the cap 7 is housed in the receiving recess 24 of the case 2, as shown in FIG. 13, the pair of outward extending portions 75 of the base portion 71 of the cap 7 engage with the cutout portions 225L of the pair of long wall portions 22L, respectively. With this configuration, the cap 7 is positioned relative to the case 2 and is prevented from swinging relative to the case 2 in the Y-axis direction.

[0028] 6 and 7, each of the pair of short wall portions 22S includes a pair of cover locking portions 222S formed on its outer surface. The pair of cover locking portions 222S are tapered portions formed on both ends of the outer surface of the short wall portion 22S in the X-axis direction and extending in the Y-axis direction. Each of the pair of cover locking portions 222S has a guide slope 2221S whose height gradually increases from above to below, and a flat portion 2222S that extends linearly downward from the top of the guide slope 2221S. The guide slope 2221S functions to guide the engagement extension portion 83 (see FIG. 3) that extends downward from the short side of the top plate 81 of the cover 8 when the cover 8 is attached to the case 2 from above. When the cover 8 is attached to the case 2 from above, the inclined portion 833 of the engaging extension portion 83 of the cover 8 slides on the guide slope 2221S, thereby opening the engaging extension portion 83 of the cover 8 outward and guiding the attachment of the cover 8 to the case 2. The flat portion 2222S engages with the locking portion 832 of the engaging extension portion 83 of the cover 8 when the cover 8 is attached to the case 2, and has the function of preventing the cover 8 from coming off the case 2. When the cover 8 is attached to the case 2 from above, when the locking portion 832 of the engaging extension portion 83 of the cover 8 climbs over the flat portion 2222S, the engaging extension portion 83 of the cover 8 elastically restores its original position inward, and the lower end surface of the flat portion 2222S engages with the upper end surface of the locking portion 832 of the engaging extension portion 83 of the cover 8, thereby locking the cover 8 to the case 2.

[0029] As shown in FIG. 6 , the storage section 23 is a recess defined by the upper surface of the bottom plate 21, the inner surfaces of the long wall portion 22L, and the inner surfaces of the short wall portion 22S, and has a substantially quadrangular (more specifically, substantially rectangular) planar shape. The storage section 23 includes a pair of slide grooves 231 and a pair of recesses 232 formed in the bottom surfaces of the pair of slide grooves 231. The pair of slide grooves 231 are grooves formed along the Z-axis direction on the inner surfaces of both wall portions of the storage section 23 in the Y-axis direction. Both ends in the Y-axis direction of a base portion 61 (see FIG. 9 ) of the pressing member 6, which will be described later, are received in the pair of slide grooves 231. When a pressing force is applied to the push switch 1, the pressing member 6 slides downward along the pair of slide grooves 231. The pair of recesses 232 are rectangular recesses formed in the bottom surfaces of the pair of slide grooves 231. When a pressing force is applied to the push switch 1 and the pressing member 6 slides downward along the pair of slide grooves 231, a pair of protrusions 63 (see Figure 9) formed on both ends of the lower surface of the base portion 61 of the pressing member 6 in the Y-axis direction are inserted into a pair of recesses 232, respectively.

[0030] Returning to FIG. 6 , the receiving recess 24 is formed on the upper end surfaces 221 of the long wall portion 22L and the short wall portion 22S and functions to accommodate the base portion 71 of the cap 7. The receiving recess 24 is formed on the upper end surfaces 221 of the long wall portion 22L and the short wall portion 22S so as to surround the accommodation portion 23 and has a planar shape corresponding to the base portion 71 of the cap 7. The depth of the receiving recess 24 is equal to or less than the thickness of the base portion 71 of the cap 7. When the push switch 1 is assembled, the base portion 71 of the cap 7 is accommodated within the receiving recess 24. Therefore, even if a strong impact, high load, or heavy load is applied to the push switch 1, the base portion 71 of the cap 7 is held within the receiving recess 24, so that the cap 7 does not become misaligned, tilted, or deformed relative to the case 2.

[0031] The sealing groove 25 is a ring-shaped groove formed on the bottom surface of the receiving recess 24 so as to surround the storage portion 23. The sealing groove 25 is formed on the bottom surface of the receiving recess 24 so as to face the sealing protrusion 76 of the cap 7 when the base portion 71 of the cap 7 is stored in the receiving recess 24. The depth of the sealing groove 25 is smaller than the length of downward protrusion of the sealing protrusion 76 of the cap 7 from the base portion 71. As described above, the depth of the receiving recess 24 of the case 2 is equal to or smaller than the thickness of the base portion 71 of the cap 7. Therefore, as shown in FIG. 13 , when the base portion 71 of the cap 7 is stored in the receiving recess 24 and the cover 8 is not attached to the case 2, the upper portion of the base portion 71 of the cap 7 protrudes upward from the receiving recess 24 of the case 2.

[0032] As will be described later, when the cap 7 is held on the case 2 by the cover 8, the sealing protrusion 76 of the cap 7 is compressed and deformed and accommodated in the sealing groove 25. As a result, the sealing protrusion 76 of the cap 7 liquid-tightly seals the sealing groove 25, providing waterproof functionality. Furthermore, because the sealing protrusion 76 of the cap 7 is compressed and deformed and accommodated in the sealing groove 25, the cap 7 is not displaced, tilted, or deformed relative to the case 2 even if a strong impact, high load, or heavy load is applied to the push switch 1. As described above, in the push switch 1 of the present invention, the receiving recess 24 and the sealing groove 25 for accommodating the base portion 71 and the sealing protrusion 76 of the cap 7, respectively, are formed on the upper end surfaces 221 of the long wall portion 22L and the short wall portion 22S of the case 2. This provides waterproof functionality for the push switch 1 and improves the impact resistance, load resistance, and load resistance of the push switch 1.

[0033] 8 shows a perspective view of the central contact 3 and outer contacts 4 (a pair of contacts) held by the case 2. The central contact 3 and outer contacts 4 (a pair of contacts) are provided spaced apart from each other on the bottom surface of the storage section 23 of the case 2. The central contact 3 and outer contacts 4 are each made of a conductive material, more specifically, a metal material such as copper. The central contact 3 and outer contacts 4 are held insulated from each other within the storage section 23 of the case 2 and function as fixed electrodes.

[0034] Each of the central contact 3 and the outer contacts 4 is obtained by punching and bending a single metal plate. The central contact 3 has a main body 31, four contact surfaces 32 that contact the second movable contact 5b, and a terminal portion 33 that extends outside the case 2. The contact surfaces 32 of the central contact 3 are exposed upward within the storage section 23 of the case 2 and are the surfaces that come into contact with the movable contact 5b when the auxiliary spring 5a and the movable contact 5b are in the second position. Furthermore, within the storage section 23 of the case 2, the four contact surfaces 32 are located above the top surface of the main body 31. The terminal portions 33 of the central contact 3 extend outward from the short wall portion (short wall portion in the -Y direction) 22S of the case 2 and function as external terminals that are connected to a circuit board or the like of an electronic device by soldering or the like.

[0035] The outer contact 4 has a main body portion 41, four contact surfaces 42 that come into contact with the second movable contact 5b, and a terminal portion 43 that extends to the outside of the case 2. The contact surfaces 42 of the outer contact 4 are exposed upward within the storage portion 23 of the case 2 and are in contact with the movable contact 5b whether the auxiliary spring 5a and the movable contact 5b are in the first position or the second position. Furthermore, within the storage portion 23 of the case 2, the four contact surfaces 42 are located above the top surface of the main body portion 41. The terminal portions 43 of the outer contact 4 extend outward from the short wall portion (short wall portion in the +Y direction) 22S of the case 2 and function as external terminals that are connected to a circuit board or the like of an electronic device by soldering or the like.

[0036] As shown in Figure 6, the central contact 3 is held by the case 2 in a state in which a portion of the main body 31 and four contact surfaces 32 of the central contact 3 are exposed upward within the storage section 23 of the case 2, and the terminal portion 33 of the central contact 3 extends outward from the short wall portion (short wall portion in the -Y direction) 22S of the case 2. The outer contacts 4 are held by the case 2 in a state in which a portion of the main body 41 and four contact surfaces 42 of the outer contact 4 are exposed upward within the storage section 23 of the case 2, and the terminal portion 43 of the outer contact 4 extends outward from the short wall portion (short wall portion in the +Y direction) 22S of the case 2. The four contact surfaces 42 of the outer contact 4 are located at the four corners of the bottom plate 21 of the storage section 23 of the case 2. The central contact 3 and the outer contacts 4 are held insulated from each other by the case 2. In addition, the surfaces of the central contact 3 and the outer contacts 4 that come into contact with the case 2 have been subjected to laser ablation (matt finish), and many minute irregularities have been formed on the surfaces of the central contact 3 and the outer contacts 4 that come into contact with the case 2. This configuration improves the degree of adhesion of the central contact 3 and the outer contacts 4 to the case 2.

[0037] Returning to Figure 5, auxiliary spring 5a and movable contact 5b are elastic conductive members having an upwardly convex dome shape, and are arranged above center contact 3 and outer contact 4 within storage section 23 of case 2. Auxiliary spring 5a is arranged above movable contact 5b, and together with movable contact 5b, provides the operating force of push switch 1 (the pressing force required to change push switch 1 from the off state to the on state) and the return force (the force that returns push switch 1 from the on state to the off state when the pressing force on push switch 1 is released) for push switch 1.

[0038] The auxiliary spring 5a and the movable contact 5b have the same configuration and are used in a stacked manner. In the illustrated embodiment, the number of auxiliary springs 5a used in a stacked manner on the movable contact 5b is one, but the present invention is not limited to this. The number of auxiliary springs 5a used in a stacked manner is set appropriately depending on the required operating force and return force of the push switch 1.

[0039] Each of the auxiliary spring 5a and the movable contact 5b has a shape that fits within the storage section 23 of the case 2. In the illustrated embodiment, each of the auxiliary spring 5a and the movable contact 5b has a substantially quadrangular (more specifically, substantially rectangular) planar shape, but the present invention is not limited to this as long as the shape fits within the storage section 23 of the case 2. For example, if the inner surface of the storage section 23 of the case 2 has a planar shape other than a substantially quadrangular shape, such as a substantially circular, elliptical, or polygonal shape, each of the auxiliary spring 5a and the movable contact 5b may have a shape that corresponds to the planar shape formed by the inner surface of the storage section 23 of the case 2 so as to fit within the storage section 23 of the case 2. Each of the auxiliary spring 5a and the movable contact 5b is configured to be displaceable between a first position where the central contact 3 and the outer contacts 4 are non-conductive and a second position where the central contact 3 and the outer contacts 4 are conductive.

[0040] Each of the auxiliary spring 5a and the movable contact 5b has a central movable portion 51 that contacts the central contact 3 and a pair of outer edge portions 52 formed at both ends of the central movable portion 51 in the Y-axis direction. As shown in the cross-sectional view of the push switch 1 in FIG. 14 , the auxiliary spring 5a and the movable contact 5b are stacked within the storage portion 23 of the case 2. In this state, the central movable portion 51 of the movable contact 5b faces the four contact surfaces 32 of the central contact 3 across a gap, and the pair of outer edge portions 52 of the movable contact 5b contact the four contact surfaces 42 of the outer contacts 4, respectively. That is, in the natural state where no pressing force is applied by the user to the push switch 1, the auxiliary spring 5a and the movable contact 5b are convex upward. In the natural state shown in FIG. 14 , the auxiliary spring 5a and the movable contact 5b are in a first position. In the first position, the movable contact 5b is not in contact with the central contact 3 but is in contact with the outer contacts 4. Therefore, when the auxiliary spring 5a and the movable contact 5b are in the first position, the central contact 3 and the outer contact 4 are in a non-conductive state.

[0041] In the natural state shown in FIG. 14 , when a user applies a pressing force to the protrusion 72 of the cap 7, the protrusion 72 of the cap 7 elastically deforms downward, pushing the pressing member 6 downward. Furthermore, as shown in FIG. 15 , the pressing member 6 presses the auxiliary spring 5a and the movable contact 5b downward, moving them from the first position to the second position. When the movable contact 5b is in the second position, the pair of outer edge portions 52 of the movable contact 5b contact the four contact surfaces 42 of the outer contact 4, respectively, and the central movable portion 51 of the movable contact 5b contacts the contact surface 32 of the central contact 3. That is, when the movable contact 5b is in the second position, it is in contact with both the central contact 3 and the outer contact 4. Therefore, when the auxiliary spring 5a and the movable contact 5b are in the second position, the movable contact 5b functions as a conductive path between the central contact 3 and the outer contact 4, and the central contact 3 and the outer contact 4 are in a conductive state. The shapes of the auxiliary spring 5a and the movable contact 5b are not necessarily limited to a dome shape, and as long as the auxiliary spring 5a and the movable contact 5b can be displaced between a first position in which the central contact 3 and the outer contact 4 are in a non-conductive state and a second position in which the central contact 3 and the outer contact 4 are in a conductive state, the auxiliary spring 5a and the movable contact 5b may have any shape.

[0042] Returning to FIG. 5, the pressing member 6 is a member made of a hard resin material such as nylon resin. The pressing member 6 is provided above the auxiliary spring 5a and the movable contact 5b and has the function of displacing the auxiliary spring 5a and the movable contact 5b from a first position to a second position by pressing the auxiliary spring 5a and the movable contact 5b downward. The pressing member 6 is housed in a pair of slide grooves 231 in the housing portion 23 of the case 2 and is located above the auxiliary spring 5a and the movable contact 5b. The pressing member 6 is used to efficiently transmit the pressing force applied to the push switch 1 by the user to the auxiliary spring 5a and the movable contact 5b, thereby pressing the auxiliary spring 5a and the movable contact 5b downward. As shown in Figures 5 and 9, the pressing member 6 includes a base portion 61 having a planar shape (approximately rectangular in the illustrated form) that fits into a pair of slide grooves 231 of the storage section 23 of the case 2, a dome-shaped lower protrusion 62 (see Figure 9) formed so as to protrude downward from approximately the center of the lower surface of the base portion 61, a pair of protrusions 63 formed at both ends in the Y-axis direction of the lower surface of the base portion 61, a rectangular upper protrusion 64 (see Figure 5) formed so as to protrude upward from approximately the center of the upper surface of the base portion 61, and a pair of positioning holes 65 formed at both ends in the Y-axis direction of the upper surface of the base portion 61.

[0043] 14, in the assembled state of the push switch 1, both ends of the base portion 61 in the Y-axis direction are housed in a pair of slide grooves 231 of the housing portion 23 of the case 2. In addition, the lower protrusion 62 is in contact with the central movable portion 51 of the auxiliary spring 5a.

[0044] Returning to Figure 5, cap 7 is made of an elastic material such as silicone rubber, and is a member that covers storage section 23 of case 2 from above. Cap 7 covers storage section 23 of case 2 from above and prevents water from entering storage section 23 of case 2, thereby providing a waterproof function for push switch 1. Furthermore, when push switch 1 is assembled, protrusion 72 of cap 7 protrudes significantly upward from cover 8, making it easy for the user to press push switch 1.

[0045] The cap 7 is arranged on the upper end surfaces 221 of the long wall portions 22L and short wall portions 22S of the case 2, and more specifically, has a substantially square (more specifically, substantially rectangular) base portion 71 that is accommodated in the receiving recess 24 of the case 2, a truncated cone-shaped protrusion 72 formed approximately in the center of the base portion 71 and protruding upward, a downward protrusion 73 (see Figure 10) formed to protrude downward from the underside of the top of the protrusion 72, a pair of positioning protrusions 74 formed on the underside of the base portion 71, a pair of outer extension portions 75 formed to extend outward from a pair of long sides of the base portion 71, and a sealing protrusion 76 that protrudes downward from the peripheral portion of the base portion 71 and liquid-tightly seals the sealing groove 25 of the case 2.

[0046] The base portion 71 of the cap 7 has a size and planar shape corresponding to the receiving recess 24 of the case 2, and is housed in the receiving recess 24 formed on the upper end surfaces 221 of the long wall portion 22L and the short wall portion 22S. As shown in FIG. 14 , when the push switch 1 is assembled, the base portion 71 of the cap 7 is held between the bottom surface of the receiving recess 24 of the case 2 and the top plate 81 of the cover 8.

[0047] The protruding portion 72 of the cap 7 is a truncated cone-shaped portion that protrudes upward from approximately the center of the base portion 71. As shown in FIG. 10, the protruding portion 72 of the cap 7 has a hollow structure. The downward protruding portion 73 of the cap 7 is a cylindrical portion that protrudes downward from the underside of the top of the protruding portion 72 of the cap 7. In the natural state of the push switch 1 shown in FIG. 14, the downward protruding portion 73 of the cap 7 faces the upper protrusion 64 of the pressing member 6.

[0048] Because cap 7 is made of an elastic material, when a user applies a pressing force so as to press down protruding portion 72 of cap 7, protruding portion 72 of cap 7 elastically deforms downward. If further pressing force is applied from this state, lower protrusion 73 of cap 7 comes into contact with upper protrusion 64 of pressing member 6, pressing down pressing member 6, and lower protrusion 62 of pressing member 6 elastically deforms auxiliary spring 5a and central movable portion 51 of movable contact 5b downward. As a result, as shown in FIG. 15 , central movable portion 51 of movable contact 5b comes into contact with contact surface 32 of central contact 3, and central contact 3 and outer contact 4 are brought into electrical continuity via movable contact 5b.

[0049] 10, the pair of positioning protrusions 74 of the cap 7 are formed at positions corresponding to the pair of positioning holes 65 of the pressing member 6. In the natural state of the push switch 1 shown in FIG. 14, the pair of positioning protrusions 74 of the cap 7 are fitted into the pair of positioning holes 65 of the pressing member 6. This structure prevents the cap 7 from swinging in the planar direction relative to the pressing member 6 and prevents the pressing member 6 from swinging up and down within the storage section 23 of the case 2.

[0050] The pair of outward extending portions 75 are rectangular portions extending outward from approximately the center of a pair of long sides of the base portion 71. As shown in Fig. 13, when the base portion 71 of the cap 7 is housed in the receiving recess 24 of the case 2, the pair of outward extending portions 75 of the cap 7 respectively engage with the pair of cutout portions 225L of the case 2. With this configuration, the cap 7 is positioned relative to the case 2 and is prevented from swinging in the Y-axis direction relative to the case 2.

[0051] Returning to FIG. 10 , the sealing protrusion 76 is a ring-shaped portion that extends downward from the periphery of the base portion 71, is formed to surround the periphery of the base portion 71, and engages with the sealing groove 25 of the case 2. The sealing protrusion 76 is formed to liquid-tightly seal the sealing groove 25 of the case 2. The sealing protrusion 76 has a tapered shape in which the thickness gradually decreases from the base end that contacts the base portion 71 toward the tip end. The tip end of the sealing protrusion 76 is rounded. The downward protrusion length (height) of the sealing protrusion 76 from the base portion 71 is greater than the depth of the sealing groove 25 of the case 2 before the sealing protrusion 76 is compressed and deformed within the sealing groove 25 of the case 2. Therefore, when the base portion 71 of the cap 7 is housed in the receiving recess 24 of the case 2, the tip end of the sealing protrusion 76 abuts against the bottom surface of the sealing groove 25 of the case 2. As a result, as shown in FIG. 13, the upper portion of the base portion 71 of the cap 7 protrudes upward from the receiving recess 24 of the case 2.

[0052] In this state, when the cover 8 is attached to the case 2 from above, the top plate 81 of the cover 8 presses downward on the base portion 71 of the cap 7, which protrudes upward from the receiving recess 24 of the case 2, thereby holding the cap 7 on the case 2. Furthermore, the pressing force applied from the top plate 81 of the cover 8 to the base portion 71 of the cap 7 compresses and deforms the sealing protrusion 76 within the sealing groove 25 of the case 2, thereby sealing the sealing groove 25 of the case 2 liquid-tightly. This configuration makes it possible to provide waterproof performance for the push switch 1.

[0053] As described above, in the push switch 1 of the present invention, the sealing protrusion 76 of the cap 7, rather than the base portion 71 of the cap 7, contacts the bottom surface of the sealing groove 25 of the case 2 and is compressed and deformed. Furthermore, the sealing protrusion 76 of the cap 7 has a tapered shape that gradually decreases in thickness toward the tip, so the contact area between the sealing protrusion 76 of the cap 7 and the bottom surface of the sealing groove 25 of the case 2 is very small. Therefore, compared to the case in which the base portion 551 of the cap 550 is pressed against the case 510 as in the prior art push switch 500 described with reference to FIGS. 1 and 2 , the contact area of ​​the cap with the case is significantly smaller. Therefore, in the push switch 1 of the present invention, the pressing force per unit area applied to the portion of the cap 7 that contacts the case 2, i.e., the sealing protrusion 76, is very large. This significantly improves the degree of adhesion of the sealing protrusion 76 of the cap 7 to the sealing groove 25 of the case 2. Therefore, even if a strong impact, high load, or heavy load is applied to the push switch 1, the sealing protrusion 76 of the cap 7 does not shift, tilt, or deform relative to the case 2, so the waterproof performance of the push switch 1 can be maintained.

[0054] Furthermore, in the push switch 1 of the present invention, the waterproof function is achieved by compressing and deforming the sealing protrusion 76 of the cap 7, which is made of an elastic material, within the sealing groove 25 of the case 2. Therefore, there is no need to use additional parts to achieve the waterproof function, and the number of parts in the push switch 1 can be reduced.

[0055] Returning to FIG. 5 , cover 8 is attached to case 2 from above so as to hold cap 7 on case 2, and has the function of holding cap 7 on case 2 by pressing down on base portion 71 of cap 7 from above. Cover 8 is obtained by punching and bending a single metal plate. Note that the material constituting cover 8 is preferably a metal material having high hardness (Vickers hardness), such as stainless steel including martensitic stainless steel and ferritic stainless steel, chromium molybdenum steel, or titanium alloy, but stainless steel, which has high hardness and excellent rust resistance, is more preferable.

[0056] As shown in FIG. 11, the cover 8 comprises a top plate 81 having a substantially quadrangular (more specifically, substantially rectangular) planar shape, an opening 82 formed in the top plate 81 for inserting the protrusion 72 of the cap 7, a pair of engaging extension portions 83 extending downward from a pair of opposing short sides (sides extending in the X direction in the figure) of the top plate 81, a pair of welding pieces 84 extending downward from a pair of opposing long sides (sides extending in the Y direction in the figure) of the top plate 81, and downward extension portions 85 extending downward from approximately the center of each of the pair of opposing long sides of the top plate 81.

[0057] When the push switch 1 is assembled, the top plate 81 holds the cap 7 on the case 2 by pressing down on the base 71 of the cap 7 from above. Furthermore, when the top plate 81 presses down on the base 71 of the cap 7, the sealing protrusion 76 of the cap 7 is compressively deformed within the sealing groove 25 of the case 2, thereby liquid-tightly sealing the inside of the sealing groove 25 of the case 2. The top plate 81 is a plate-like portion having a planar shape (in the illustrated embodiment, a substantially rectangular planar shape) corresponding to the base 71 of the cap 7. The opening 82 is formed in approximately the center of the top plate 81 so that the protrusion 72 of the cap 7 can be inserted upward when the push switch 1 is assembled. In the illustrated embodiment, the shape of the opening 82 is approximately oval corresponding to the shape of the protrusion 72 of the cap 7, but is not particularly limited as long as it allows the protrusion 72 of the cap 7 to be inserted upward.

[0058] The pair of engaging extensions 83 are formed to lock the cover 8 to the case 2. As shown in Fig. 11, the pair of engaging extensions 83 extend downward from each of a pair of opposing short sides (sides extending in the X direction in the figure) of the top plate 81. Each of the pair of engaging extensions 83 has a pair of legs 831 extending downward from the short sides of the top plate 81, a locking portion 832 connecting the lower tips of the pair of legs 831, and a pair of inclined portions 833 formed at the lower end of the locking portion 832.

[0059] The pair of legs 831 extend linearly downward while being spaced apart from each other from the short sides of the top plate 81. The distance between the outer side surfaces of the pair of legs 831 is approximately equal to the distance between the inner side surfaces of a pair of cover locking portions 222S formed on the outer surface of the short wall portion 22S of the case 2. Therefore, as shown in FIG. 3, when the cover 8 is attached to the case 2, the outer side surfaces of the pair of legs 831 engage with the inner side surfaces of the pair of cover locking portions 222S of the case 2, respectively, preventing the cover 8 from swinging in the X-axis direction relative to the case 2.

[0060] Returning to FIG. 11 , the locking portion 832 is a portion that is elongated in the X-axis direction and connects the lower tip ends of the pair of leg portions 831. As shown in FIGS. 3 and 4 , the lower end surfaces of the flat portions 2222S of a pair of cover locking portions 222S formed on the outer surfaces of the short wall portions 22S of the case 2 engage with the upper end surfaces of the locking portions 832, thereby locking the cover 8 to the case 2. The pair of inclined portions 833 are formed at the lower end of the locking portion 832 so as to extend diagonally downward (outward) while being spaced apart from each other. The inclination of the pair of inclined portions 833 is approximately equal to the inclination of the guide slopes 2221S of the pair of cover locking portions 222S formed on the outer surfaces of the short wall portions 22S of the case 2. Therefore, when the cover 8 is pushed into the case 2 from above, the pair of inclined portions 833 of the cover 8 slides on the guide slopes 2221S of the pair of cover locking portions 222S of the case 2, and the engaging extensions 83 of the cover 8 open outward. Therefore, the pair of inclined portions 833 have the function of facilitating attachment of the cover 8 to the case 2 when assembling the push switch 1.

[0061] Returning to FIG. 11 , the pair of welding pieces 84 are plate-shaped portions extending downward from, and spaced apart from, each of the pair of long sides of the top plate 81. As shown in FIG. 4 , when the cover 8 is attached to the case 2, the pair of welding pieces 84 are received in first receiving grooves 2241L formed on the outer surfaces of the long wall portions 22L of the case 2. Returning to FIG. 11 , the inner surfaces of the pair of welding pieces 84 are welding surfaces 841 that are welded to the welding pieces 84 of the frame 9. The downward extending portions 85 are plate-shaped portions extending downward from, each of the pair of long sides of the top plate 81. The downward extending portions 85 are located between, and spaced apart from, the pair of welding pieces 84. The downward extending portions 85 have engagement recesses 851 formed at their lower ends. 4, when the cover 8 is attached to the case 2, the engaging recess 851 of the downward extending portion 85 engages with the central protrusion 222L formed on the outer surface of the long wall portion 22L of the case 2, preventing the cover 8 from swinging in the Y-axis direction on the case 2. In addition, the downward extending portion 85 covers the outer extending portion 75 of the cap 7 from the outside.

[0062] When the cover 8 is attached to the case 2, the upper end faces 221 of the long wall portions 22L and short wall portions 22S of the case 2 are supported from the outside by the top plate 81 of the cover 8, the upper portions of the long wall portions 22L of the case 2 are supported from the outside by the welded pieces 84 and downward extensions 85 of the cover 8, and further, the upper portions of the short wall portions 22S of the case 2 are supported from the outside by the engaging extensions 83 of the cover 8. As a result, the upper portions of the case 2 are reinforced by the cover 8.

[0063] Returning to FIG. 5, frame 9 is attached to case 2 from below and has the function of supporting case 2 from below. Frame 9 is obtained by punching and bending a single metal plate. The material constituting frame 9 is preferably a metal material having high hardness (Vickers hardness), such as stainless steel including martensitic stainless steel and ferritic stainless steel, chromium molybdenum steel, or titanium alloy, but stainless steel, which has high hardness and excellent rust resistance, is more preferable.

[0064] As shown in Figure 12, the frame 9 comprises a bottom plate 91 having a substantially quadrangular (more specifically, substantially rectangular) planar shape, a pair of engagement portions 92 extending upward from each of a pair of opposing long sides of the bottom plate 91, and a pair of welding pieces 93 extending upward from each of a pair of opposing long sides of the bottom plate 91.

[0065] The bottom plate 91 is a plate-like portion having a shape corresponding to the recess 211 formed on the bottom surface of the bottom plate 21 of the case 2, which was described in detail with reference to FIG. 7. As shown in FIG. 4, when the frame 9 is attached to the case 2, the bottom plate 91 is housed in the recess 211 of the case 2, and the frame 9 is integrated with the case 2. This prevents deformation such as distortion or warping of the case 2 when a strong impact or a high load is applied to the push switch 1, and prevents changes in the characteristics of the push switch 1 due to deformation of the case 2. Therefore, the push switch 1 of the present invention has excellent impact resistance, load resistance, and load resistance.

[0066] Returning to FIG. 12 , the bottom plate 91 has an opening 911 formed in approximately its center and a pair of notches 912 formed on a pair of its short sides. The opening 911 has a shape corresponding to the protrusion 212 formed on the bottom surface of the bottom plate 21 of the case 2. The pair of notches 912 are formed on a pair of opposing short sides of the bottom plate 91 so as to sandwich the opening 911 in the Y-axis direction. Each of the pair of notches 912 has a shape corresponding to a pair of horizontal extensions 213 formed on the bottom surface of the bottom plate 21 of the case 2. As shown in FIG. 4 , when the frame 9 is attached to the case 2, the opening 911 of the frame 9 engages with the protrusion 212 of the case 2, and further, the pair of notches 912 of the frame 9 engage with the pair of horizontal extensions 213 of the case 2. This configuration prevents the frame 9 from swinging in the planar direction relative to the case 2.

[0067] Returning to FIG. 12 , the pair of engagement portions 92 are formed to extend upward from each of a pair of opposing long sides of the bottom plate 91. Each of the pair of engagement portions 92 has a linear portion 921 that extends upward in a straight line from the long side of the bottom plate 91, and a locking portion 922 formed at the tip of the linear portion 921. As shown in FIGS. 3 and 4 , when the frame 9 is attached to the case 2, the linear portion 921 is located in the space between a central protrusion 222L formed on the outer surface of the long wall portion 22L of the case 2 and the frame locking portion 223L. In this way, the linear portion 921 is held between the central protrusion 222L and the frame locking portion 223L, preventing the frame 9 from swinging in the Y-axis direction relative to the case 2.

[0068] The locking portion 922 is a portion that extends outward from the tip of the straight portion 921. As shown in FIG. 12 , a guide slope 9221 is formed on the inside of the tip of the locking portion 922. The inclination of the guide slope 9221 is approximately equal to the inclination of the guide slope 2231L of the frame locking portion 223L formed on the outer surface of the long wall portion 22L of the case 2. Therefore, when the frame 9 is pushed into the case 2 from below, the locking portion 922 of the frame 9 slides on the guide slope 2231L of the frame locking portion 223L of the case 2, and the engaging portion 92 of the frame 9 opens outward. Therefore, the guide slope 9221 functions to facilitate attachment of the frame 9 to the case 2 when assembling the push switch 1. Furthermore, as shown in Figures 3 and 4, the upper end surface of the flat portion 2232L of the frame locking portion 223L formed on the outer surface of the long wall portion 22L of the case 2 engages with the lower end surface of the locking portion 922, thereby locking the frame 9 to the case 2.

[0069] The pair of welding pieces 93 are plate-shaped portions extending linearly upward while being spaced apart from each other from both ends of a pair of opposing long sides of the bottom plate 91. The pair of welding pieces 93 are received in second receiving grooves 2242L formed on the outer surfaces of the long wall portions 22L of the case 2. The outer surfaces of the pair of welding pieces 93 form welding surfaces 931 that are welded to the welding surfaces 841 of the pair of welding pieces 84 of the cover 8, respectively. As shown in FIG. 4 , when the frame 9 is attached to the case 2 from below, the welding pieces 93 of the frame 9 are received in the second receiving grooves 2242L of the case 2. As described above, the depth of the second receiving grooves 2242L of the case 2 is approximately equal to the thickness of the welding pieces 93 of the frame 9, and therefore the bottom surfaces of the first receiving grooves 2241L of the case 2 and the upper surfaces of the welding pieces 93 of the frame 9 are positioned approximately flush with each other. When the cover 8 is attached to the case 2 from above with the frame 9 attached to the case 2, the welded piece 84 of the cover 8 is housed in the first receiving groove 2241L of the case 2.

[0070] In this state, the welding piece 84 of the cover 8, which is housed in the first receiving groove 2241L of the case 2, is positioned on the welding piece 93 of the frame 9, which is housed in the second receiving groove 2242L of the case 2. Furthermore, the welding surface 931 of the welding piece 93 of the frame 9 is in contact with the welding surface 841 of the welding piece 84 of the cover 8. Furthermore, the welding surface 931 of the welding piece 93 of the frame 9 and the welding surface 841 of the welding piece 84 of the cover 8 are welded to each other by any welding method such as thermal welding or laser welding, typically laser welding, thereby firmly fixing the cover 8 and the frame 9 together. In this way, the case 2 is firmly held between the cover 8 and the frame 9, which are welded to each other.

[0071] When the frame 9 is attached to the case 2, the bottom panel 21 of the case 2 is supported from the outside by the bottom plate 91 of the frame 9, and the lower portion of the long wall portion 22L of the case 2 is supported from the outside by the engagement portion 92 and the welded piece 93 of the frame 9. As a result, the lower portion of the case 2 is reinforced by the cover 8.

[0072] In the push switch 1 of the present invention, the weld surface 931 of the weld piece 93 of the frame 9 is welded to the weld surface 841 of the weld piece 84 of the cover 8, so the cover 8 and the frame 9, which hold the case 2 from above and below, are firmly fixed to each other. Therefore, even if a strong impact, a high load, or a heavy load is applied to the push switch 1, the engagement of the cover 8 with the case 2 does not loosen because the cover 8 is firmly fixed to the frame 9 that is integrated with the case 2. Therefore, the pressure of the sealing protrusion 76 of the cap 7 inside the sealing groove 25 of the case 2 does not loosen, and the sealing groove 25 of the case 2 is maintained by the sealing protrusion 76 of the cap 7. For these reasons, the waterproof performance of the push switch 1 can be maintained even if a strong impact, a high load, or a heavy load is applied to the push switch 1.

[0073] Furthermore, in the push switch 1 of the present invention, the case 2 is supported and reinforced from above, below, and laterally by the cover 8 and the frame 9, thereby suppressing deformation such as warping and warping of the case 2 when a strong impact or a high load is applied to the push switch 1. In particular, the cover 8 and the frame 9 are made of a metal material (such as stainless steel) that has a higher hardness (Vickers hardness) than the insulating resin that constitutes the case 2. Therefore, by supporting the case 2 from above, below, and laterally with the cover 8 and the frame 9, the case 2 is reinforced and deformation of the case 2 can be more effectively suppressed. In this way, in the push switch 1 of the present invention, the case 2 is sandwiched between the cover 8 and the frame 9 from above and below, and further, the cover 8 and the frame 9 are welded and firmly fixed to each other, preventing deformation of the case 2. Therefore, the push switch 1 of the present invention has excellent impact resistance, load-bearing capacity, and load-bearing capacity.

[0074] The procedure for assembling the push switch 1 described in detail will be described below. First, the auxiliary spring 5a and the movable contact 5b are placed one on top of the other in the storage section 23 of the case 2, which holds the center contact 3 and the outer contact 4. Next, both ends of the base portion 61 of the pressing member 6 are inserted into the pair of slide grooves 231 in the storage section 23 of the case 2, and the pressing member 6 is placed on the auxiliary spring 5a. Next, the base portion 71 of the cap 7 is stored in the receiving recess 24 of the case 2. At this time, the sealing protrusion 76 of the cap 7 is inserted into the sealing groove 25 formed in the receiving recess 24 of the case 2. Figure 13 is a perspective view showing the base portion 71 of the cap 7 stored in the receiving recess 24 of the case 2.

[0075] As described above, when the sealing protrusion 76 of the cap 7 is not compressively deformed, the downward protrusion length of the sealing protrusion 76 of the cap 7 from the base portion 71 is greater than the depth of the sealing groove 25 of the case 2, and the depth of the receiving recess 24 of the case 2 is equal to or less than the thickness of the base portion 71 of the cap 7. Therefore, as shown in FIG. 13 , the upper portion of the base portion 71 of the cap 7 protrudes upward from the receiving recess 24 of the case 2. In this state, the frame 9 is attached to the case 2 from below. Then, the cover 8 is attached to the case 2 from above, and the cover 8 engages with the case 2. When the cover 8 engages with the case 2, the top plate 81 of the cover 8 presses downward against the upper portion of the base portion 71 of the cap 7 that protrudes upward from the receiving recess 24 of the case 2, thereby holding the cap 7 on the case 2. Furthermore, the sealing protrusion 76 of the cap 7 is compressively deformed within the sealing groove 25 of the case 2 due to the pressing force applied from the top plate 81 of the cover 8 to the base portion 71 of the cap 7. The compressive deformation of the sealing protrusion 76 of the cap 7 within the sealing groove 25 of the case 2 seals the sealing groove 25 of the case 2 liquid-tightly, thereby providing the push switch 1 with waterproof performance.

[0076] In the above description, the frame 9 is attached to the case 2 after the auxiliary spring 5a, the movable contact 5b, the pressing member 6, and the cap 7 are housed in the case 2, but the present invention is not limited to this. The frame 9 may be attached to the case 2 before the auxiliary spring 5a, the movable contact 5b, the pressing member 6, and the cap 7 are housed in the case 2.

[0077] 4 , when the cover 8 and the frame 9 are attached to the case 2, the welding piece 93 of the frame 9 is positioned inside the welding piece 84 of the cover 8, and the welding surface 931 of the welding piece 93 of the frame 9 comes into contact with the welding surface 841 of the welding piece 84 of the cover 8. Next, the welding surface 931 of the welding piece 93 of the frame 9 and the welding surface 841 of the welding piece 84 of the cover 8 are welded (typically, by laser welding), and the welding surface 931 of the welding piece 93 of the frame 9 and the welding surface 841 of the welding piece 84 of the cover 8 are welded together, and the cover 8 and the frame 9 are firmly fixed to each other. When the case 2 is sandwiched and held from above and below by the cover 8 and the frame 9 that are firmly fixed to each other, the assembly of the push switch 1 is completed.

[0078] Next, the operation of the push switch 1 will be described in detail with reference to Figures 14 and 15. Figure 14 shows a vertical cross-sectional view of the push switch 1 taken along line AA in Figure 3 in a natural state where no pressing force is applied to the push switch 1. Figure 15 shows a vertical cross-sectional view of the push switch 1 taken along line AA in Figure 3 in a pressed state where a pressing force exceeding the actuating force of the push switch 1 is applied to the push switch 1.

[0079] As shown in FIG. 14, in the natural state of the push switch 1, the auxiliary spring 5a and the movable contact 5b are convex upward. In the state shown in FIG. 14, the auxiliary spring 5a and the movable contact 5b are in a first position. In the first position, the outer edge 52 of the movable contact 5b is in contact with the contact surface 42 of the outer contact 4, and the central movable portion 51 of the movable contact 5b is not in contact with the contact surface 32 of the central contact 3. In other words, when the movable contact 5b is in the first position, it is not in contact with the central contact 3, but is in contact with the outer contact 4. Therefore, when the auxiliary spring 5a and the movable contact 5b are in the first position, the central contact 3 and the outer contact 4 are not electrically connected.

[0080] 14, when the user applies a pressing force to the protruding portion 72 of the cap 7, the protruding portion 72 of the cap 7 elastically deforms downward. When further pressing force is applied from this state, the lower protrusion 73 of the cap 7 comes into contact with the upper protrusion 64 of the pressing member 6, pressing the pressing member 6 downward, and the lower protrusion 62 of the pressing member 6 elastically deforms the auxiliary spring 5a and the central movable portion 51 of the movable contact 5b downward. As a result, the auxiliary spring 5a and the movable contact 5b are displaced to the second position, and the push switch 1 transitions to the pressed state shown in FIG. 15.

[0081] In the pressed state shown in FIG. 15 , the auxiliary spring 5a and the movable contact 5b are in the second position. In the second position, the outer edge 52 of the movable contact 5b is in contact with the contact surface 42 of the outer contact 4, and the central movable portion 51 of the movable contact 5b is in contact with the contact surface 32 of the central contact 3. That is, when the movable contact 5b is in the second position, it is in contact with both the central contact 3 and the outer contact 4. Therefore, when the auxiliary spring 5a and the movable contact 5b are in the second position, the movable contact 5b functions as a conductive path between the central contact 3 and the outer contact 4, and the central contact 3 and the outer contact 4 are in a conductive state. When the pressing force against the protrusion 72 of the cap 7 is released in the pressed state shown in FIG. 15 , the return force of the push switch 1 provided by the elastic restoring force of the auxiliary spring 5a and the movable contact 5b restores the push switch 1 to its natural state shown in FIG. 14 .

[0082] While the push switch of the present invention has been described above based on the illustrated embodiment, the present invention is not limited to this. Each component of the present invention can be replaced with any component that can perform the same function, or any component can be added to each component of the present invention.

[0083] Those skilled in the art and technology to which the present invention pertains will be able to modify the configuration of the push switch of the present invention as described without significantly departing from the principles, concepts, and scope of the present invention, and push switches having modified configurations are also within the scope of the present invention.

[0084] 3 to 15 are merely examples for the purpose of explanation, and the present invention is not necessarily limited thereto. The scope of the present invention also includes embodiments in which any component is added or combined, or any component is deleted, as long as it does not deviate from the principles and intent of the present invention.

[0085] For reference, accurate six-sided views of the push switch of the present invention are shown in Figs. 16 to 21. Fig. 16 is a plan view of the push switch of the present invention. Fig. 17 is a bottom view of the push switch of the present invention. Fig. 18 is a front view of the push switch of the present invention. Fig. 19 is a rear view of the push switch of the present invention. Fig. 20 is a left side view of the push switch of the present invention. Fig. 21 is a right side view of the push switch of the present invention. [Explanation of symbols]

[0086] DESCRIPTION OF SYMBOLS 1...push switch 2...case 21...bottom plate 211...recess 212...protrusion 213...horizontal extension 22L...long wall 222L...central protrusion 223L...frame locking portion 2231L...guide inclined surface 2232L...flat portion 224L...receiving groove 2241L...first receiving groove 2242L...second receiving groove 225L...notch 22S...short wall 222S...cover locking portion 2221S...guide inclined surface 2222S...flat portion 221...upper end surface 23...storage portion 231...slide groove 232...recess 24...receiving recess 25...sealing groove 3...central contact 31...main body 32...contact surface 33...terminal portion 4...outer contact 41...main body 42...contact surface 43...Terminal portion 5a...Auxiliary spring 5b...Moveable contact 51...Central movable portion 52...Outer edge portion 6...Pressing member 61...Base portion 62...Lower protrusion 63...Protrusion 64...Upper protrusion 65...Positioning hole 7...Cap 71...Base portion 72...Protrusion portion 73...Downward protrusion 74...Positioning protrusion 75...Outer extension portion 76...Sealing protrusion 8...Cover 81...Top plate 82...Opening 83...Engaging extension portion 831...Leg portion 832...Latching portion 833...Inclined portion 84...Welding piece 841...Welding surface 85...Downward extension portion 851...Engaging recess 9...Frame 91...Bottom plate 911...Opening 912...Notch portion 92...Engaging portion 921...Straight portion 922...Latching portion 9221...Guide inclined surface 93...welding piece 931...welding surface 500...push switch 510...case 511...bottom plate 512...wall portion 513...storage portion 514...engaging protrusion 5141...inclined surface 5142...flat portion 520...center contact 530...outer contact 540...movable contact 550...cap 551...base portion 552...protrusion 560...cover 561...top plate 562...opening 563...extension portion 5631...leg portion 5632...bridge portion

Claims

1. a case including a storage section defined by a bottom plate and a plurality of wall portions extending upward from the bottom plate, and a sealing groove formed on an upper end surface of the plurality of wall portions; a pair of contacts spaced apart from each other and provided on the bottom plate within the storage section; a movable contact disposed above the pair of contacts in the storage section, the movable contact being displaceable between a first position where the pair of contacts are in a non-conductive state and a second position where the pair of contacts are in a conductive state; a cap that covers the storage section of the case from above, the cap including: a flat base section that is disposed on the upper end surfaces of the plurality of wall sections of the case; a protruding section that protrudes upward from the base section; and a sealing protrusion that protrudes downward from a peripheral edge of the base section and that liquid-tightly seals the sealing groove of the case; a cover including a top plate and an opening formed in the top plate to allow the protruding portion of the cap to pass through, the cover being attached to the case from above to hold the cap on the case; When the cap is held on the case by the cover, the sealing protrusion of the cap is compressed and deformed in the sealing groove of the case, thereby sealing the sealing groove of the case liquid-tightly; the case further includes a pair of cover locking portions formed spaced apart from each other on each of a pair of opposing wall portions among the plurality of wall portions, the cover further includes a pair of engagement extensions extending downward from a pair of opposing sides of the top plate, Each of the pair of engaging extension portions includes a pair of legs extending downward from the side of the top plate while being spaced apart from each other, and a locking portion connecting lower tip ends of the pair of legs, outer side surfaces of the pair of legs of the engagement extension portion extending from the side of the top plate engage with inner side surfaces of the pair of cover locking portions formed on the pair of opposing wall portions of the case, A push switch characterized in that the upper end surface of the locking portion of the engaging extension portion extending from the edge of the top plate engages with the lower end surfaces of the pair of cover locking portions formed on the wall portion of the case.

2. the case further includes a receiving recess formed on the upper end surfaces of the plurality of wall portions so as to surround the storage portion, 2. The push switch according to claim 1, wherein the base portion of the cap is housed within the receiving recess in the case.

3. The sealing groove of the case is formed on a bottom surface of the receiving recess so as to surround the storage portion, 3. The push switch according to claim 2, wherein the sealing protrusion of the cap is formed to go around the periphery of the base portion of the cap and engage with the sealing groove.

4. When the base portion of the cap is housed in the receiving recess of the case, the base portion of the cap protrudes upward from the receiving recess, 4. The push switch according to claim 2, wherein when the cover is attached to the case, the top plate of the cover presses the base portion of the cap downward, thereby compressing and deforming the sealing protrusion of the cap within the sealing groove of the case.

5. 5. A push switch as described in any one of claims 1 to 4, wherein the downward protrusion length of the sealing protrusion of the cap from the base portion is greater than the depth of the sealing groove of the case before the sealing protrusion of the cap is compressed and deformed within the sealing groove.

6. A case comprising: a storage section defined by a bottom plate and a plurality of wall portions extending upward from the bottom plate; and a sealing groove formed on the upper end surfaces of the plurality of wall portions; a pair of contacts spaced apart from each other and provided on the bottom plate within the storage section; a movable contact disposed above the pair of contacts in the storage section, the movable contact being displaceable between a first position where the pair of contacts are in a non-conductive state and a second position where the pair of contacts are in a conductive state; a cap that covers the storage section of the case from above, the cap including: a flat base section that is disposed on the upper end surfaces of the plurality of wall sections of the case; a protruding section that protrudes upward from the base section; and a sealing protrusion that protrudes downward from a peripheral edge of the base section and that liquid-tightly seals the sealing groove of the case; a cover including a top plate and an opening formed in the top plate to allow the protruding portion of the cap to pass through, the cover being attached to the case from above to hold the cap on the case; When the cap is held on the case by the cover, the sealing protrusion of the cap is compressed and deformed in the sealing groove of the case, thereby sealing the sealing groove of the case liquid-tightly; The cap further includes a pair of outward extending portions extending outward from a pair of opposing sides of the base portion, the case further includes a pair of notches formed on the upper end surfaces of the wall portions, A push switch, characterized in that the pair of outward extending portions of the cap engage with the pair of notched portions of the case.

7. A case comprising: a storage section defined by a bottom plate and a plurality of wall portions extending upward from the bottom plate; and a sealing groove formed on the upper end surfaces of the plurality of wall portions; a pair of contacts spaced apart from each other and provided on the bottom plate within the storage section; a movable contact disposed above the pair of contacts in the storage section, the movable contact being displaceable between a first position where the pair of contacts are in a non-conductive state and a second position where the pair of contacts are in a conductive state; a cap that covers the storage section of the case from above, the cap including: a flat base section that is disposed on the upper end surfaces of the plurality of wall sections of the case; a protruding section that protrudes upward from the base section; and a sealing protrusion that protrudes downward from a peripheral edge of the base section and that liquid-tightly seals the sealing groove of the case; a cover including a top plate and an opening formed in the top plate to allow the protruding portion of the cap to pass through, the cover being attached to the case from above to hold the cap on the case; a frame including a bottom plate and attached to the case from below; When the cap is held on the case by the cover, the sealing protrusion of the cap is compressed and deformed in the sealing groove of the case, thereby sealing the sealing groove of the case liquid-tightly; the case is held between the cover and the frame, The top plate of the cover has a substantially rectangular planar shape, the cover further includes a pair of welding pieces extending downward from each of a pair of opposing sides of the top plate; the bottom plate of the frame has a substantially rectangular planar shape, the frame further includes a pair of welding pieces extending upward from a pair of opposing sides of the bottom plate, A push switch characterized in that the pair of welding pieces of the cover are welded to the pair of welding pieces of the frame, respectively, thereby holding the case between the cover and the frame which are welded to each other.

8. the case further includes a pair of receiving grooves formed on outer surfaces of a pair of opposing wall portions of the plurality of wall portions, Each of the pair of receiving grooves includes a first receiving groove for accommodating the welding piece of the cover and a second receiving groove for accommodating the welding piece of the frame, the weld piece of the cover housed in the first receiving groove is positioned on the weld piece of the frame housed in the second receiving groove; 8. The push switch according to claim 7, wherein an inner surface of the welding piece of the cover is welded onto an outer surface of the welding piece of the frame.

9. 9. The push switch according to claim 7, wherein the welding piece of the cover is laser-welded to the welding piece of the frame.

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