JP2013186993A - Push-on switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a push-on switch related to the one used for an input operation part of various electronic devices and operated by being pressed in a horizontal direction to a wiring board, with a configuration that achieves prevention of static electricity and mounting in a low height state.SOLUTION: A push-on switch is provided with a case 1 having a recessed part 1A in which a switch contact part including a movable contact 6, a central fixed contact 2 and outer fixed contacts 3 are provided, where the switch contact part is operated by operating an operation body 8 assembled in the case 1 movably in a front and rear direction. The push-on switch is configured such that: terminals 2A from the central fixed contact 2 and terminals 3A from the outer fixed terminals 3 are respectively lead out from half-height positions of left and right side surfaces of the case 1; and each tip end of leg parts 29C, each of which is formed by being extended in the same direction, in top view, as the lead out direction of the terminal 3A from a metal cover 29 fixed to the case 1 and being bent downwards, is arranged adjacent with a predetermined gap to the upper surface of the terminal 3A connected to the ground of a wiring board 31.

Description

  The present invention relates to a push-on switch used for an input operation unit of various electronic devices.

  In recent years, various electronic devices have progressed without being limited in function as electronic devices become smaller and lighter and thinner, and the input operation unit has a direction parallel to the wiring board of the mounted electronic device. The use of small and thin push-on switches operated from the beginning is increasing.

  Such a conventional push-on switch will be described with reference to FIGS.

  FIG. 12 is an external perspective view of a conventional push-on switch, FIG. 13 is a cross-sectional view thereof, FIG. 14 is an exploded perspective view thereof, FIG. 15 is an external perspective view for explaining a form of mounting, and FIG. It is an external perspective view.

  In the figure, reference numeral 1 denotes an insulating resin case having a concave portion 1A having an upper opening. A central fixed contact 2 is disposed at the center of the bottom surface of the concave portion 1A. A pair of outer fixed contacts 3 that are substantially rectangular and project slightly upward are disposed. The terminal 2 </ b> A connected to the center fixed contact 2 and the terminal 3 </ b> A connected to the outer fixed contact 3 are led out from the intermediate height positions on the left and right side surfaces of the case 1, respectively. That is, those lead-out positions are set at positions higher than the bottom surface position of the case 1.

  In the left and right side portions where the terminals 2A and 3A of the case 1 are led out, the side surface of the case 1 located above the lower surface position of the terminals 2A and 3A protrudes outward from the side surface located below. It has become. That is, the left and right side portions of the case 1 are formed in a horizontal step shape in which the lower portion is cut inward, and the lower surface of the step portion and the lower surfaces of the terminals 2A and 3A are at the same height position. . A receiving portion 1B is formed by the lower surface of the stepped portion and the lower surfaces of the terminals 2A and 3A.

  At the four corners of the upper surface of the case 1, corner protrusions 1 </ b> C that are L-shaped when viewed from above are formed to protrude upward.

  Reference numeral 6 denotes a movable contact made of an elastic metal thin plate having an upward convex circular dome shape, and the lower end of the outer periphery thereof is placed on the outer fixed contact 3 and is accommodated in the recess 1 </ b> A of the case 1. The lower surface of the central portion of the movable contact 6 is opposed to the upper surface of the central fixed contact 2 with a gap.

  A protective sheet 7 made of an insulating film is attached to the upper surface of the case 1 with an adhesive (not shown) provided on the lower surface so as to cover the concave portion 1A of the case 1 in a state where the movable contact 6 described above is accommodated. .

  8 is a resin-made operating body that is incorporated so as to be movable in the front-rear direction with respect to the case 1, and an operating portion 8A that protrudes forward and a circle that protrudes rearward from the central rear portion of the operating portion 8A. It has a columnar drive part 8B and a frame part 8D surrounding the drive part 8B in a U-shape. The tip of the drive unit 8B is a pressing unit 8C formed in a substantially spherical shape.

  The operating body 8 is arranged on the case 1 so that the frame portion 8D is positioned in the region surrounded by the corner protrusion 1C of the case 1, and the left and right direction of the frame portion 8D is the inner wall of the corner protrusion 1C. While being guided, the side surface is movable in the front-rear direction. In the arrangement state, the operation portion 8 </ b> A protrudes forward from the outer peripheral position of the case 1.

  A metal cover 9 made of a metal plate is fixed to the case 1 so as to cover the operating body 8 from above. The metal cover 9 includes an inclined portion 9B that is bent and formed at the center position of the flat plate portion 9A located above the case 1 so that the front end side is inclined downward downward. The lower surface of the inclined portion 9B is in contact with the pressing portion 8C at the tip of the driving portion 8B of the operating body 8.

  The conventional push-on switch is configured as described above, and the operation thereof will be described next.

  When the operation portion 8A is pushed rearward from the front, the pressing portion 8C moves along the lower surface of the inclined portion 9B of the metal cover 9. That is, the pressing portion 8 </ b> C moves obliquely downward while bending the driving portion 8 </ b> B obliquely downward, and the central portion of the movable contact 6 is pressed by the pressing portion 8 </ b> C via the protective sheet 7. When this pressing force exceeds a certain value, the central portion of the movable contact 6 is elastically inverted with a click feeling, and the lower surface of the central portion of the movable contact 6 and the central fixed contact 2 come into contact with each other. As a result, the corresponding terminals 2A and 3A are brought into conduction and are switched on.

  When the force that has pushed the operating body 8 is released, the movable contact 6 is elastically restored to its original shape and pushes the pressing portion 8C upward, and the pressing portion 8C is guided by the lower surface of the inclined portion 9B and the driving portion 8B It returned to the original shape and returned to the switch-off state in which the operating body 8 was pushed back to the original forward position.

  The push-on switch described above is used by being mounted on a wiring board of an electronic device typified by a mobile terminal. Next, the mounting state and the like will be described with reference to FIGS.

  As shown in the figure, at the end position of the wiring board 11, a notch portion 11 </ b> A having a concave shape in a U shape is provided on the inside as viewed from above. Then, terminal lands 12 and 13 corresponding to the terminals 2A and 3A of the push-on switch are respectively disposed on the left and right side positions of the notch 11A. The lands 12 and 13 are connected to an electronic circuit (not shown) of the wiring board 11.

  The push-on switch is configured so that the operation portion 8A is positioned in the forward direction on the opening side of the cutout portion 11A and the rear portion is brought into contact with the end surface on the depth side of the cutout portion 11A. The receiving portion 1B is placed on the upper surface position of the wiring board 11 in the vicinity of the notch portion 11A, and the terminals 2A and 3A are soldered and mounted on the corresponding lands 12 and 13, respectively.

  As described above, the push-on switch is mounted with the lower portion of the case 1 below the receiving portion 1B positioned in the notch portion 11A, and the height of the push-on switch is reduced in the height direction when mounted on the wiring board 11. It was possible to make it. In addition, since the rear portion of the push-on switch is in a mounting state in which the push-on switch is brought into contact with the end surface on the depth side of the cutout portion 11A, even if an excessive force is applied to the push-on switch on the rear side unexpectedly, Further, it was possible to achieve a mounting state in which peeling from the wiring board 11 was prevented.

  As prior art document information related to the invention of this application, for example, Patent Document 1 is known.

JP 2010-118336 A

  In recent electronic devices, in order to prevent the malfunction and failure of electronic devices due to electrostatic discharge, so-called ESD, there are many demands for electronic components with countermeasures against static electricity. Was growing.

  However, with the progress of downsizing of electronic devices, device manufacturers prefer to use various electronic components with a small mounting area, and are particularly mounted at end positions of the wiring board 11 such as a conventional push-on switch. In order to secure a mounting area for other electronic components, there is an increasing demand for a configuration in which countermeasures against static electricity are taken without increasing the depth dimension at the end position.

  The present invention solves such a conventional problem, and push-on having a configuration that can be mounted in a low-profile state with countermeasures against static electricity without increasing the size of the push-on switch in the front-rear direction, that is, in the depth direction. The object is to provide a switch.

  In order to achieve the above object, the present invention is mounted with the lower part of the case positioned in the notch of the wiring board, and the switch contact part is activated by pressing in a direction parallel to the upper surface of the wiring board. A push-on switch is formed at a predetermined interval with respect to a terminal formed by being led out toward at least one side of both sides of the cut-out portion. The push-on switch is characterized in that it has a configuration close to each other.

  In this case, the static electricity that has flowed into the push-on switch can be reduced without increasing the dimension in the depth direction by connecting the terminal close to the static electricity induction portion to the ground (GND) of the wiring board. The push-on switch can be realized as a small-sized push-on switch that can be mounted in a low-profile state and can be placed on the ground (GND) of the electronic device through the induction unit.

  According to the present invention, it is possible to provide an advantageous effect that it is possible to provide a push-on switch having a small configuration with an ESD countermeasure that can be mounted in a low profile without increasing the dimension in the depth direction.

1 is an external perspective view of a push-on switch according to an embodiment of the present invention. Cross section Front view Bottom view Exploded perspective view External perspective view explaining the form to be mounted External perspective view showing the same mounting state External perspective view of a push-on switch according to another embodiment of the present invention Front view Exploded perspective view Same circuit diagram External perspective view of a conventional push-on switch Cross section Exploded perspective view External perspective view explaining the form to be mounted External perspective view showing the same mounting state

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the part of the structure same as the structure demonstrated in the term of the prior art, and detailed description is simplified.

(Embodiment)
1 is an external perspective view of a push-on switch according to an embodiment of the present invention, FIG. 2 is a sectional view thereof, FIG. 3 is a front view thereof, FIG. 4 is a bottom view thereof, FIG. FIG. 7 is an external perspective view for explaining the mounting form, and FIG. 7 is an external perspective view showing the mounting state.

  As shown in the figure, the push-on switch according to the present invention has a case 1 made of an insulating resin, like the conventional one. The case 1 is formed in a substantially rectangular shape when viewed from above, and includes a concave portion 1A (see FIG. 5) having an upper opening. A central fixed contact 2 is disposed at the center of the bottom of the recess 1A, and is formed to protrude slightly upward in a substantially rectangular shape when viewed from above at a position on the outer peripheral side of the bottom of the recess 1A with the center fixed contact 2 as the center. A pair of outer fixed contacts 3 are arranged. A terminal 2A connected to the central fixed contact 2 and a terminal 3A connected to the outer fixed contact 3 are led out from the left and right side surfaces of the case 1, respectively.

  Note that the lead-out height positions of the terminals 2A and 3A from the case 1 are the same, and are led out horizontally from the side surface position of the intermediate height higher than the bottom face position of the case 1, and are higher than the bottom face positions of the terminals 2A and 3A. The upper side surface of the case 1 has a horizontal step shape that protrudes outward from the lower side surface, and a receiving portion 1B is formed by the lower surface of the step portion and the lower surfaces of the terminals 2A and 3A. It is the same as the conventional one.

  And in the recessed part 1A of case 1, the movable contact 6 which consists of a circular dome-shaped elastic metal thin plate is accommodated similarly to the past. Further, the upper part of the recess 1A is covered with a protective sheet 7 bonded to the upper surface of the case 1 as in the conventional case. Here, in the said structure, the switch contact part is comprised by the movable contact 6, the center fixed contact 2, and the outer side fixed contact 3. FIG.

  The operating body 8 is arranged such that the operating portion 8A protrudes forward of the case 1 and the frame portion 8D is located in a region surrounded by the corner protruding portion 1C of the case 1. This operation body 8 is also the same as the conventional one, and a drive portion 8B extending behind the operation portion 8A is provided in the frame portion 8D, and the tip of the drive portion 8B is formed into a substantially spherical pressing portion 8C. The frame 8D is incorporated so as to be movable in the front-rear direction with respect to the case 1 while being guided by the inner wall of the corner projection 1C.

  Furthermore, a metal cover 29 made of a metal plate is fixed to the case 1 so as to cover the operating body 8 from above. The metal cover 29 includes a flat plate portion 29A located above the case 1, and an inclined portion 29B formed at the center of the flat plate portion 29A so as to be bent so that the front end side is inclined downward downward. The lower surface of the inclined portion 29B is in contact with the pressing portion 8C at the tip of the driving portion 8B of the operating body 8.

  Here, according to this embodiment, of the terminals 2A and 3A, two of the terminals 3A connected to the outer fixed contact 3 are connected to the ground side of the device and used. In the cover 29, a single leg portion 29 </ b> C having a predetermined width is directed laterally from a side position substantially the same as the lead-out position of the terminal 3 </ b> A led out from the front side surface of the case 1 from the flat plate portion 29 </ b> A in a top view. Are used. The leg portion 29C is bent downward along the side surface of the case 1, and the tip of the leg portion 29C is spaced from the upper surface of the root portion of the corresponding one of the terminals 3A by a predetermined distance. It is in close proximity.

  Here, the leg portion 29C corresponds to the static electricity induction portion of claim 1, and the distance between the tip of the leg portion 29C and the upper surface of the one terminal 3A is set to 0.1 mm or less. . In addition, it is desirable that the range facing the upper surface of the terminal 3A at the tip of the leg 29C is also large. Furthermore, it is desirable that the other outer edge portion of the metal cover 29 is separated by a distance of more than 0.15 mm at a position closest to the terminal 2A. That is, it is preferable that the difference between the two is ensured to be larger than 0.05 mm. Thus, in the component, the metal cover 29 is configured such that only the leg portion 29C is close to the one terminal 3A and the other outer edge portion of the metal cover 29 is separated from the terminal 2A.

  As described above, the push-on switch according to the present embodiment is configured.

  Since the operation is the same as the conventional one, it will be briefly described below. When the operating portion 8A of the operating body 8 is pushed rearward, the operating body 8 moves rearward, and the central portion of the movable contact 6 is pressed by the pressing portion 8C guided obliquely downward by the inclined portion 29B of the metal cover 29. Is pressed. When this pressing force exceeds a certain value, the movable contact 6 is elastically reversed with a click feeling, and the central part of the movable contact 6 is brought into contact with the central fixed contact 2 to switch between the terminals 2A and 3A. It becomes a state. Then, when the force that has pushed the operating body 8 backward is released, the movable contact 6 is elastically restored to the original upward convex shape to push the pressing portion 8C upward, and the pressing portion 8C While the drive unit 8B returns to the original shape while moving obliquely upward along the lower surface of the inclined portion 29B, the operating body 8 is pushed back to the original position and returns to the switch-off state shown in FIGS.

  Next, the mounting state of the above-described push-on switch will be described with reference to FIGS.

  In the figure, reference numeral 31 denotes a wiring board provided with a notch 31A having a shape recessed in a U-shape inside in an end position when viewed from above. Terminal lands 32 and 33 corresponding to the terminals 2A and 3A of the push-on switch are respectively disposed on the left and right lateral positions of the cutout portion 31A. The terminal land 32 is connected to an electronic circuit (not shown) of the wiring board 31, and the terminal land 33 is connected to the ground or GND of the wiring board 31.

  Here, the ground connected to the terminal land 33 is common to the GND of the electronic circuit, that is, the so-called signal GND, and the electronic circuit detects that the switch is turned on when the terminal lands 32 and 33 become conductive. It is supposed to be.

  In the push-on switch, the lower part of the case 1 is accommodated in the notch 31A, and the receiving part 1B of the case 1 is placed on the upper surface of the wiring board 31 in the vicinity of the notch 31A. The terminal 2A is mounted on the corresponding terminal land 32 and the terminal 3A is mounted on the corresponding terminal land 33 by soldering. Therefore, the terminal 3A soldered and fixed to the terminal land 33 has the same potential as the ground of the wiring board 31, and the leg 29C of the push-on switch is connected to the ground of the wiring board 31 via the one terminal 3A and zero. The proximity state is 1 mm or less. In addition, when mounted on the wiring board 31, the leg portion 29 </ b> C of the metal cover 29 is closest to the ground of the wiring board 31, and other outer edge portions of the metal cover 29 are not close to the ground of the wiring board 31. It is good to be.

  As described above, the push-on switch according to this embodiment can be mounted in a state in which the leg portion 29 </ b> C is close to the ground of the wiring board 31. Therefore, even when static electricity flows into the push-on switch from the user's fingertip or the like through the operation buttons of the electronic device when the electronic device is used, the static electricity is provided on the legs provided on the metal cover 29. A gap between the portion 29C and the one terminal 3A on the side facing the leg portion 29C can be discharged, and the static electricity can be passed to the ground of the wiring board 31. That is, the electrostatic potential is remarkably higher than the ground potential of the wiring board 31, and the static electricity that has flowed into the push-on switch is opposed to the leg portion 29C serving as an electrostatic induction portion having the smallest insulation distance. The air layer between the first terminal 3A (0.1 mm or less) is dielectrically broken and placed on the ground of the wiring board 31. As described above, since the metal cover 29 and the terminal 2A are separated by a distance greater than 0.15 mm and the dielectric breakdown is unlikely to occur, the inflowing static electricity is stably grounded. You can smell.

  As a result, it is possible to prevent the malfunction or damage of the electronic circuit due to the static electricity that has flowed in.

  The leg portion 29C is extended to the lateral sides of the left and right sides of the cutout portion 31A when viewed from the top, and the leg portion 29C has a slightly extended length when viewed from the top. Therefore, since it has a shape bent downward along the side surface of the case 1 so as to be accommodated in one terminal 3A, the component can be mounted within the same occupied area as the conventional product. it can.

  Furthermore, since the terminals 2A and 3A that are soldered and fixed at the time of mounting have the same shape as the conventional one, the shape and arrangement position of the terminal lands 32 and 33 of the wiring substrate 31 to be mounted are the same as those of the conventional wiring substrate 11. Can be useful.

  As described above, the push-on switch configured as described above can discharge the static electricity flowing into the push-on switch to the ground (GND) of the electronic device through the static electricity induction unit without increasing the dimension in the depth direction. It can be provided as a push-on switch having a small configuration with countermeasures.

  Furthermore, the push-on switch according to this embodiment is mounted on the wiring board 31 with the lower part of the case 1 positioned in the notch 31A, so that the height from the upper surface of the wiring board 31 is low. Can be implemented in a simple manner. Furthermore, since the rear part of the push-on switch is mounted so as to be in contact with or close to the end face on the depth side of the notch 31A, an excessive force is applied to the unexpected rear side or the like. In addition, the rear part of the push-on switch is supported by the end face on the depth side of the cutout part 31 </ b> A, so that problems such as peeling from the wiring board 31 are less likely to occur.

  In the mounted state, since the height dimension from the upper surface of the wiring board 31 can be reduced, the metal cover 29 is also positioned at a low position and extended from the side to the side. The bending down dimension of the leg 29C may be short. For this reason, it can be easily realized that there is little fluctuation of the bent tip position and the distance between the leg portion 29C and the corresponding one terminal 3A is small.

  Furthermore, since the push-on switch according to the present embodiment has a configuration in which a gap of a predetermined distance is provided between the leg portion 29C and the corresponding one terminal 3A, the one terminal 3A is deformed by the leg portion 29C. The metal cover 29 can be easily assembled to the case 1 and can be stably mounted on the wiring board 31 including the one terminal 3A.

  Further, the extension length of the leg portion 29C in a top view is slight, and if the bent portion is bent down along the side surface of the case 1, the leg portion 29C is expected. Even when a force is applied to the inside of the case 1, the bent portion of the leg portion 29C is supported by the side surface of the case 1, so that the degree of deformation of the leg portion 29C is suppressed, and the leg portion 29C and It is preferable because a predetermined interval between the corresponding terminals 3A is easily maintained.

  In the above description, the leg portion 29C of the metal cover 29 is provided only at one place, but both sides are provided so as to correspond to each one of the terminals 3A provided on the left and right sides of the case 1. Each may be provided with a leg portion and may have a plurality of static electricity induction portions. Further, the terminal 3A on the side close to the leg portion 29C may be configured to be in an electrically independent state from the central fixed contact 2 or the outer fixed contact 3, and in this case, static electricity is grounded. Otosu electric circuit can be configured independently.

  Moreover, the thing of the said embodiment makes the leg part 29C extended and protruded to the side according to the terminal 3A of the case 1 front, and the static electricity which flows in from a user's fingertip is the front of the case 1 Although it is assumed that the inflow of static electricity to the terminal 2A behind the terminal connected to the signal line of the electronic circuit is prevented as being connected to the ground of the wiring board 31 via the terminal 3A, there is no particular limitation. That is, it is sufficient if the leg portion is extended to the side on both sides of the cutout portion 31A of the wiring board 31. For example, in addition to the above configuration, the leg portion is extended at a position corresponding to the rear terminal 2A. It is also possible to have a leg configuration in which the tip is close to the upper surface of the terminal 2A. In this case, a terminal land connected to the ground of the wiring board may be arranged on the terminal 2A side, and a terminal land connected to the signal line of the electronic circuit may be arranged on the terminal 3A side.

  In addition, as described above, if the leg portion 29C serving as a static electricity induction portion is provided integrally with the metal cover 29, the inflowing static electricity is grounded to the electronic device with the metal cover 29 as the main, with a simple configuration. It is desirable that static electricity does not easily flow into the push-on switch so that it can escape, and it is desirable that better ESD countermeasures are taken. However, the present invention is not limited to this. For example, the static electricity induction unit is independent of the metal cover 29. It may be provided.

  The shape of the movable contact 6 may also be other than a circular shape when viewed from above. For example, a polygonal shape, an oval shape, a dome portion provided with a central hole, or a shape provided with a plurality of legs extending radially from the outer peripheral end when viewed from above. It may be used as long as it can be switched according to the movable contact used as the fixed contact.

  In addition, although what demonstrated the switch operation | movement of 1 step | stage with only one movable contact was demonstrated above, a switch contact part is not limited only to the thing of the structure mentioned above. For example, the idea of the present invention can be applied to a push-on switch capable of a plurality of stages of switch operation by combining the plurality of movable contacts described above. Next, I will describe the case.

  8 is an external perspective view of a push-on switch according to another embodiment of the present invention, FIG. 9 is a front view thereof, FIG. 10 is an exploded perspective view thereof, and FIG. 11 is a circuit diagram thereof.

  As shown in the figure, in the push-on switch, three pairs of terminals 42A, 43A, and 44A are led out from the left and right side surfaces of the case 41, respectively. The lead-out height positions of the terminals 42A, 43A, 44A are all the same, and the side surface of the case 41 located above the lower surface position has a step shape protruding in the left-right direction, and the lower surface of the step portion and the terminals 42A, 43A. The receiving portion 41B is formed with the lower surface of 44A.

  A protective sheet 47 is bonded to the upper surface of the case 41 and covers a recess (not shown) provided in the case 41. A plurality of movable contacts (not shown) are accommodated in the recesses of the case 41. In addition, a plurality of fixed contacts (not shown) connected to the terminals 42A, 43A, 44A, respectively, are arranged on the inner bottom surface of the recess, and a switch contact capable of performing a two-stage switch between these movable contacts and fixed contacts. The part is formed.

  Above the case 41, an operating body 48 is mounted in a frame surrounded by corner protrusions 41C formed in an L shape at the four corners of the case 41, and is incorporated so as to be movable in the front-rear direction. ing. Further, a metal cover 49 made of a metal plate is fixed to the case 41 so as to cover the operating body 48 from above.

  The operating body 48 is the same as the conventional one, and an operating portion 48A that protrudes forward and protrudes forward from the outer peripheral position of the case 41, a driving portion 48B that extends rearward of the operating portion 48A, and a driving portion 48B. A frame portion 48D is enclosed in a U-shape, and the tip of the drive portion 48B is formed in a substantially spherical pressing portion 48C. Further, the metal cover 49 is also provided with a flat plate portion 49A located above the case 41 and an inclined portion 49B that is bent and formed obliquely downward toward the rear at the center position of the flat plate portion 49A. In the metal cover 49, the lower surface of the inclined portion 49 </ b> B is in contact with the pressing portion 48 </ b> C at the tip of the driving portion 48 </ b> B of the operating body 48.

  Here, one leg portion 49C extending from the metal cover 49 has a predetermined width from the flat plate portion 49A, as viewed from above, from a side position substantially the same as the terminal 44A derived from the front side surface of the case 41. The tip that is extended and bent downward along the side surface of the case 41 is in an opposed state in which it is close to the upper surface of the root of the corresponding one of the terminals 44A with a predetermined distance. The leg portion 49C corresponds to the static electricity induction portion of claim 1. The push-on switch is configured as described above.

  The push-on switch is also mounted so that the lower portion of the case 41 is accommodated in a notch portion of a wiring board (not shown) as in the prior art, and the terminals 42A, 43A, 44A are soldered to the corresponding terminal lands. Used fixed. Further, the operation is substantially the same, and when the operation portion 48A of the operating body 48 is pressed from the front to the rear, the movable portion (not shown) is moved by the pressing portion 48C guided obliquely downward by the inclined portion 49B of the metal cover 49. The contact is pressed and switched, and the electrical connection state to the wiring board, the switch operation, and the like will be briefly described with reference to the circuit diagram of FIG.

  The push-on switch is used with the terminal 44A connected to the ground of the wiring board. The terminals 42A and 43A are connected to an electronic circuit (not shown) through terminal lands disposed on the wiring board. In the electronic circuit, the signal GND is common to the ground of the wiring board, and the continuity between the terminals 43A and 44A is detected as the first switch-on, and thereafter, all the terminals 42A, 43A and 44A are connected to each other. The conductive state is detected as the second switch-on.

  When the operation portion 48A of the operation body 48 is pressed backward, the pressing portion 48C of the operation body 48 presses a movable contact (not shown) via the protective sheet 47. When the pressing force exceeds a predetermined value, the movable contact performs a predetermined operation, and the fixed contacts connected to the terminals 43A and 44A are electrically connected. That is, SW1 in FIG. 11 is connected, and the first stage switch is switched on. When the operation unit 48A is further pressed, the fixed contact connected to the terminal 42A is further connected between the fixed contacts connected to the terminals 43A and 44A by the predetermined operation of the movable contact while maintaining the switch-on state of the first stage switch. The conductive state is established, SW2 is connected, and the second stage switch is switched on. When the pressing force to the operation unit 48A is released, the above-described operation is reversed and the second-stage switch is switched off, and then the first-stage switch is switched off.

  Here, also in the push-on switch according to the present embodiment, in the mounting state on the wiring board, the mounting state in which the terminal 44A in which the tip of the leg portion 49C is close to the wiring board with a predetermined interval is connected to the ground of the wiring board. Therefore, the static electricity that has flowed into the push-on switch can be transferred to the ground of the wiring board from the leg portion 49C provided on the metal cover 49.

  Thereby, the inflow of static electricity to the terminals 42A and 43A can be prevented, and the malfunction or damage of the electronic circuit due to static electricity can be prevented.

  In addition, the structure of the switch contact part for switching in two steps is not specifically limited. Further, the mechanism for operating the switch contact portion is not limited to the above-described mechanism, and further, the switch setting of the circuit by the switch contact portion is other than that interlocked as described above. Also good.

  In the above, an example in which the present invention is applied to a so-called lateral push type that can be mounted in a low-profile state while utilizing the notch portion of the wiring board has been described. It is applied to a general lateral push type mounted on a wiring board that is not provided with a portion, or a so-called vertical push type that is pressed vertically downward with respect to the mounted wiring board surface. You may apply.

  The push-on switch according to the present invention has a small configuration that allows static electricity flowing into the push-on switch to be grounded to the ground (GND) of the electronic device without increasing the dimension in the depth direction, and can be mounted in a low-profile state. It can be provided as a device and is useful mainly for an input operation unit of an electronic device.

DESCRIPTION OF SYMBOLS 1,41 Case 1A Concave part 1B, 41B Receiving part 1C, 41C Corner protrusion 2 Center fixed contact 2A, 3A, 42A, 43A, 44A Terminal 3 Outer fixed contact 6 Movable contact 7, 47 Protective sheet 8, 48 Manipulator 8A, 48A Operation part 8B, 48B Drive part 8C, 48C Press part 8D, 48D Frame part 29, 49 Metal cover 29A, 49A Flat part 29B, 49B Inclined part 29C, 49C Leg part 31 Wiring board 31A Notch part 32, 33 For terminals land

Claims (2)

A push-on switch that is mounted with a lower portion of a case positioned in a notch portion of a wiring board, and that is operated by pressing in a direction parallel to the upper surface of the wiring board to operate a switch contact portion. The static electricity induction part provided in the push-on switch is configured to be close to the terminal formed by being led out toward at least one side of both sides of the switch at a predetermined interval. Push-on switch. The push-on switch according to claim 1, further comprising a metal cover that covers the case from above, wherein the static electricity induction portion is extended from the metal cover.

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