JP2012146484A - Push switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-stage action push switch that ensures an operation stroke of a lower movable contact (first stage) and makes a small operation sound.SOLUTION: A lower movable contact 40 comprises a circular part 41 having a center hole 41a and a plurality of legs 42 extended from the outer peripheral portion of the circular part 41, the circular part 41 being formed in a flat shape. Each leg 42 comprises a leg base 41a composed of a part of the outer peripheral portion of the circular part 41, an upper leg piece part 42c extending downwardly as inclined from the leg base 41a via a first bending part 42b, and a lower leg piece part extending from the upper leg piece part 42c via a second bending part 42d below the upper leg piece part 42c. Each leg 42 comprises a substantially U-shaped leaf spring formed therein and supports the circular part 41 in a vertically movable manner on the installation surface of the lower movable contact 40.

Description

  The present invention relates to a push switch used in an input operation unit of various electronic devices, and in particular, a movable contact is incorporated in two upper and lower stages, the first stage switch is turned on by a pressing operation, and the second stage is further pressed. The present invention relates to a two-stage push switch that is turned on.

  In a normal two-stage push switch, a circular dome-shaped metal plate (circular dome-shaped plate spring) bulging upward is used for the upper movable contact, and the lower movable contact is smaller in diameter than the upper movable contact. A circular dome-shaped metal plate (circular dome-shaped plate spring) is used. When the central part of the upper movable contact is pushed down, it reverses and contacts the central part of the opposing lower movable contact, and always touches the outer peripheral edge of the lower movable contact with the first click The fixed contact and other peripheral fixed contacts that are always in contact with the outer peripheral edge of the upper movable contact are conducted through the lower movable contact and the upper movable contact, and the first-stage switch is turned on. Further, the first stage operation sound is generated when the central portion of the upper movable contact is reversed. When the central portion of the upper movable contact is further pushed down, the central portion of the lower movable contact is reversed and comes into contact with the opposing central fixed contact, and with a second click feeling, the central fixed contact and the peripheral fixed contact Are conducted through the lower movable contact, and the second-stage switch is turned on. Also, a second stage operation sound is generated when the center of the lower movable contact is reversed.

  In the above normal two-stage push switch, in order to increase the operation stroke of each movable contact, a circular dome-shaped metal plate having a large outer diameter is required, and the concave portion of the body for accommodating them must be enlarged. However, there has been a problem that the outer shape of the body is enlarged.

  In order to solve the above problem, the push switch of the two-stage operation described in Patent Document 1 is provided with grooves on the inner side walls of the recesses corresponding to the four corners of the body, and the upper movable contact is obliquely downward from the outer peripheral edge. It uses a dome-shaped metal plate with legs that are continuously extended with four legs so as to be inclined and located in the groove of the body, ensuring an operating stroke of the upper movable contact (first stage), and body The size is reduced. A normal circular dome-shaped metal plate is used for the lower movable contact.

  However, the two-stage push switch described in Patent Document 1 has the upper movable contact in the first-stage reversal operation and the lower movable contact in the second-stage reversal operation in the same manner as the normal two-stage push switch. When the center of the upper movable contact is pressed until the center of the lower movable contact is reversed (the second-stage switch is turned on), the upper movable contact is deformed until a considerable stress is applied. For this reason, there is a problem that the lifetime is shorter than that of the lower movable contact.

  On the other hand, the two-stage push switch described in Patent Document 2 is provided with a leg having a large circular hole at the center of the lower movable contact with respect to the dome-shaped metal plate with the leg. A dome-shaped metal plate is used, and a normal circular dome-shaped metal plate is used for the upper movable contact, and the upper movable contact is placed on an annular portion around the central hole of the lower movable contact.

  Unlike the normal two-stage push switch and the two-stage push switch described in Patent Document 1, the two-stage push switch described in Patent Document 2 is lower when the central portion of the upper movable contact is pushed down. The annular part of the movable contact is pushed down, it reverses and contacts multiple peripheral fixed contacts facing each other, and the multiple peripheral fixed contacts are conducted through the lower movable contact with the first click Then, the first-stage switch is turned on. Further, the first stage operation sound is generated when the annular portion of the lower movable contact is reversed. When the central portion of the upper movable contact is further pushed down, it is reversed and comes into contact with the central fixed contact that opposes through the central hole of the lower movable contact. The fixed contact is conducted through the lower movable contact and the upper movable contact, and the second-stage switch is turned on. Further, a second stage operation sound is generated when the central portion of the upper movable contact is reversed.

  In the two-stage push switch described in Patent Document 2, the lower movable contact is in the first-stage reversal operation, the upper movable contact is in the second-stage reversal operation, and only the lower movable contact is deformed in the first stage. Since only the upper movable contact is deformed, a substantially equivalent life can be secured for the lower movable contact and the upper movable contact. However, since the central portion (annular portion) of the lower movable contact is inverted in a dome shape with a central hole, there is a problem that the operation stroke of the lower movable contact (first stage) is small and the operation sound is large.

JP 2003-7168 A JP 2008-41603 A

  An object of the present invention is to solve the above-mentioned problems and to provide a push switch of a two-stage operation that secures the operation stroke of the lower movable contact (first stage) and has a low operation sound.

  In order to solve the above-mentioned problems, the present invention provides, as a first means, a box-shaped body 1 made of an insulating resin having a recess 2 having an opening on the top surface and a plurality of grooves 3 on the inner wall, A central fixed contact 10 disposed at the center of the bottom surface, a plurality of peripheral fixed contacts 20, 30 disposed outside the central fixed contact 10, and a plurality of peripheral holes 20a accommodated in the recess 2 are provided with a plurality of central holes 41a. A plurality of leg portions 42 arranged to correspond to the plurality of groove portions 3 extending from the outer peripheral edge portion of the annular portion 41 and arranged to face the peripheral fixed contacts 20, 30. A lower movable contact 40 made of a metal plate having a central portion that is placed on the annular portion 41 and whose outer peripheral edge is always in contact with the annular portion 41 and is reversible. Bulges upwardly arranged oppositely through the hole 41a An upper movable contact 50 made of a dome-shaped metal plate, the annular portion 41 is formed in a flat plate shape, and each leg portion 42 is provided with a first bent portion 42b from the outer peripheral edge portion of the annular portion 41. Via the upper leg piece 42c that is inclined downwardly toward the inner lower part of the groove part 3 and the front side of the inner wall of the concave part 2 in the inner part of the groove part 3 from the upper leg piece part 42c. A lower leg piece 42e extending below the upper leg piece 42c via a second bent part 42d arranged with a predetermined gap G on the side, and each leg 42 is substantially U-shaped leaf springs are respectively formed, the lower leg piece 42e is brought into contact with the inner bottom surface of the recess 2 in the groove 3, and the annular portion 41 and the upper movable contact 50 placed thereon are placed. Are supported so as to be vertically movable, and the outer peripheral edge of the annular portion 41 A plurality of notch portions 41b and 41c are provided on both side edges of the first bent portion 42b of the portion 42, and each leg portion 42 is also provided with each notch portion pair 41b and 41c in the annular portion 41. A base portion 42a composed of a portion sandwiched between the notch portions 41b and 41c is provided, and each leg portion 42 includes a base portion 42a, a first bent portion 42b, and an upper leg piece portion 42c. A buckled folding plate having the first bent portion 42b as a top portion is formed, and the outer peripheral edge of the upper movable contact 50 is connected to the outer peripheral edge of the annular portion 41 and the first of the leg portions 42. The bent portion 42b or the base portion 42a is in contact.

  According to the first means, the lower movable contact 40 (first stage) has a conventional lower movable contact (inverted in a dome shape with a central hole) when the central portion of the upper movable contact 50 is pushed down. Unlike the first stage, the annular portion 41 is pushed down in a flat plate shape, and each leg portion (substantially U-shaped leaf spring) 42 spreads outward while being compressed and deformed at the same time. The bent portion 42d simultaneously strikes the inner wall of the recess 2 in the inner part of each groove 3 of the body 1 so that the inner wall of the recess 2 in the inner part of each groove 3 of the body 1 and the flat annular part 41 are formed. A plurality of peripheral fixed contacts 20, each of which has a bent plate (base portion 42a, first bent portion 42b, and upper leg piece portion 42c) buckled all at once, 30 is contacted. Then, the plurality of peripheral fixed contacts 20 and 30 are brought into conduction via the lower movable contact 40, and the first-stage switch is turned on. As described above, the lower movable contact 40 performs the first stage operation without the inversion of the annular portion 41, but the operation stroke can be secured by simultaneous compression deformation of each leg portion 42, and the folding of each leg portion 42 can be performed. A click feeling can be imparted by simultaneous buckling of the plate. Further, each leg portion 42 which is smaller than the annular portion 41, and the folded plate which is a part of each leg portion 42 is further buckled, the first stage operation sound is reduced. When the central portion of the upper movable contact 50 is further pushed down, it is reversed and comes into contact with the central fixed contact 10 facing through the central hole 41a of the lower movable contact 40, with a second click feeling. The fixed contact 10 and the peripheral fixed contact 20 are conducted through the lower movable contact 40 and the upper movable contact 50, and the second-stage switch is turned on. Thus, a two-stage push switch can be obtained.

  Further, in the present invention, as the second means, in the first means, each leg portion 42 is further extended obliquely upward from the lower leg piece portion 42e via the third bent portion 42f. Each of the leg portions 42 forms a cantilever-like return auxiliary leaf spring by each of the extension portions 42g. After the folded plate is buckled, the distal end side of the extended portion 42g is brought into contact with the root portion 42a and pushed down, and the extended portion 42g biases the root portion 42a upward.

  According to the second means, when the first-stage switch is in the ON state, the lower movable contact 40 is connected to the annular portion 41 and the leg portions 42 by the extension portions (return auxiliary leaf springs) 42g of the leg portions 42. Since the base portion 42a of each leg portion 42, which is a continuous portion of the upper movable contact 50, is urged upward, when the depression of the central portion of the upper movable contact 50 is released, before the central portion of the upper movable contact 50 is depressed. It is possible to more reliably return to the state of no operation.

  According to the present invention, it is possible to provide a push switch of a two-stage operation that secures the operation stroke of the lower movable contact (first stage) 40 and has a low operation sound.

It is a disassembled perspective view which shows the component of the push switch by one Embodiment of this invention. It is a perspective view which shows the external appearance of the push switch by one Embodiment of this invention. FIG. 3 is a cross-sectional view taken along the line Z-Z in FIG. It is a top view which shows the accommodation state of the upper and lower movable contact with respect to the recessed part of the body of the push switch by one Embodiment of this invention. It is a top view which shows the accommodation state of the lower movable contact with respect to the recessed part of the body of the push switch by one Embodiment of this invention. It is a top view which shows the body of the push switch by one Embodiment of this invention. It is FIG. 6Z1-Z1 sectional drawing which shows the body of the push switch by one Embodiment of this invention. It is a top view which shows the lower movable contact of the push switch by one Embodiment of this invention. FIG. 9 is a cross-sectional view of FIG. 8Z2-Z2 illustrating a lower movable contact of a push switch according to an embodiment of the present invention. It is a top view which shows the upper movable contact of the push switch by one Embodiment of this invention. FIG. 10X is a cross-sectional view illustrating the upper movable contact of the push switch according to the embodiment of the present invention. FIG. 3 is a cross-sectional view taken along the line Z-Z in FIG. 2, illustrating a state immediately before the first-stage switch is turned on when the push switch is pressed from a non-operating state according to an embodiment of the present invention. FIG. 3 is a cross-sectional view taken along the line Z-Z in FIG. 2, illustrating a state when the push switch of the push switch according to the embodiment of the present invention is turned on. FIG. 3 is a cross-sectional view taken along the line Z-Z in FIG. 2, illustrating a state when the push switch of the push switch according to the embodiment of the present invention is turned on.

  Hereinafter, a push switch according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 to 3, the push switch of the present embodiment includes a body 1, a center fixed contact 10, first and second peripheral fixed contacts 20 and 30, lower and upper movable contacts 40 and 50, The insulating cover 60 and the metal cover 70 are included.

  As shown in FIGS. 6 and 7, the body 1 is formed of an insulating synthetic resin and has a circular outer shape having a circular concave portion 2 having an upper surface opened inside.

  Square first grooves 3 are provided at four locations on the inner wall of the recess 2 corresponding to the four corners of the body 1.

  Of the two sets of opposing outer walls of the body 1, square second grooves 4 are provided at two locations on the inner wall of the recess 2 corresponding to the central portion in the length direction of the pair of opposing outer walls. In addition, square-shaped protrusions 5 are provided at two locations on the inner wall of the recess 2 corresponding to the center in the length direction of the remaining pair of outer walls.

  At the center of the inner bottom surface of the recess 2 of the body 1, a central fixed contact 10 formed in a cylindrical shape with a conductive metal is disposed in a state of protruding upward.

  A first peripheral fixed contact 20 formed of a conductive metal in a quadrangular prism shape is located at one of the two locations on the outer side of the inner bottom surface of the recess 2 corresponding to the two second groove portions 4 of the body 1. The second peripheral fixed contact 30 formed of a conductive metal in the shape of a quadrangular prism is disposed in a protruding state in the remaining one place.

  The first and second peripheral fixed contacts 20, 30 are outside the center fixed contact 10 on the inner bottom surface of the recess 2 of the body 1, and are outside at two points on the point-symmetric outer part with the center fixed contact 10 as a symmetric point. The substantially half part enters the second groove part 4, and the inside substantially half part is disposed in a state of protruding into the recessed part 2 in the same manner as the two protruding parts 5 of the body 1.

  Out of two sets of opposing outer walls of the body 1, both ends of the pair of outer walls facing the first and second peripheral fixed contacts 20, 30 in a direction perpendicular to the direction facing the central fixed contact 10. The connection terminals 11, 21 made of conductive thin metal plates derived from the central fixed contact 10 and the first and second peripheral fixed contacts 20, 30 for connection to a circuit board such as a device. 31 is disposed.

  One of the first peripheral fixed contact 20 and its connection terminal 21 and the second peripheral fixed contact 30 and its connection terminal 31, for example, the first peripheral fixed contact 20 and its connection terminal 21 are the first and second. The common contact terminals of the switch, that is, the common contact and the common connection terminal.

  As shown in FIG. 7, the vertical structure of the recess 2 of the body 1 is parallel to the inner bottom surface of the recess 2 at a height h1 from the inner bottom surface of the recess 2 (the installation surface of the lower movable contact 40). A flat upper surface 10a of the center fixed contact 10 is disposed in the plane, and the two protrusions 5 of the body 1 are located in a plane at a height h2 (h1 <h2) above it. A flat upper surface 5a is provided, and the upper surfaces 20a and 30a of the first and second peripheral fixed contacts 20 and 30 are within one plane at a height h3 (h1 <h2 <h3) above the flat upper surface 5a. Are arranged respectively.

  As shown in FIGS. 8 and 9, the lower movable contact 40 is made of a single conductive metal thin plate, and includes the upper surface 5 a of the two protrusions 5 of the body 1 and the first and second peripheral fixed contacts 20 and 30. The outer shape of the body 1 is such that a circular center hole 41a having a diameter larger than the outer diameter (diameter) of the central fixed contact 10 is provided in the center so as to be opposed to each other above the upper surfaces 20a and 30a. A circular annular portion 41 having a smaller diameter than the outer diameter (diameter) of the recess 2 and concentric with the central hole 41a, and an outer peripheral edge portion of the annular portion 41 so as to be positioned in the four first groove portions 3 of the body 1 And four leg portions 42 having a width smaller than the width of each first groove portion 3 of the body 1 continuously extending in four directions.

  The annular portion 41 is formed in a flat plate shape.

  Each leg portion 42 includes an upper leg piece portion 42c that extends downwardly from the outer peripheral edge portion of the annular portion 41 via a first bent portion 42b, and a second bent portion (from the upper leg piece portion 42c). A lower leg piece 42e extending at an interval below the upper leg piece 42c via a folded portion 42d, and each leg 42 has a substantially U-shaped leaf spring. Form.

  A plurality of pairs of notches 41 b and 41 c are provided on the outer peripheral edge of the annular portion 41 so as to be continuous with both side edges of the first bent portion 42 b of each leg portion 42.

  Each leg portion 42 is provided with a root portion 42a composed of a portion sandwiched between the notch portions 41b and 41c in the pair of notch portions 41b and 41c in the annular portion 41, and each leg portion 42 has a root portion 42a. The part 42a, the first bent part 42b, and the upper leg piece part 42c form a buckled folding plate having the first bent part 42b as the top.

  Each leg portion (substantially U-shaped leaf spring) 42 is compressed and deformed simultaneously with a pressing force smaller than the pressing force with which the folded plate (base portion 42a, first bending portion 42b, and upper leg piece portion 42c) is buckled all at once. The folded plates are then buckled all together with a pressing force smaller than the pressing force at which the central portion of the upper movable contact 50 is reversed.

  Each leg 42 extends from the lower leg piece 42e via the third bent part 42f so as to be inclined upward, and the distal end is disposed opposite to the base part 42a with a gap therebetween. Each leg 42 forms a cantilever-like return auxiliary leaf spring by the extension 42g.

  The extension portion (recovery auxiliary leaf spring) 42g is bent obliquely downward in the vicinity of the tip, and is formed in a generally U shape. The fourth bent portion (the top of the extension portion 42g) in the vicinity of the tip of the extension 42g As a pressing part (contact part) 42h, it is arranged below the base part 42a with a space therebetween.

  As shown in FIGS. 3 and 5, in the lower movable contact 40, each leg portion 42 corresponding to each first groove portion 3 of the body 1 is disposed in the first groove portion 3, and the upper leg piece portion of each leg portion 42. 42c extends from the base portion 42a through the first bent portion 42c so as to incline downward toward the inner bottom portion of the first groove portion 3, and the second bent portions 42d of the respective leg portions 42 are respectively first. It is arranged with a predetermined gap G on the front side of the inner wall of the recess 2 in the inner part of the groove 3, and at four locations on the outer side of the inner bottom surface of the recess 2 in each first groove 3 of the body 1. The corresponding lower leg piece portion 42e of each leg portion 42 is brought into contact with the outer side of the inner bottom surface of the recess 2 and is accommodated in the recess 2 of the body 1. In this state, the annular portion 41 provided with the central hole 41a is lifted and supported by the leg portions 42 so as to be movable in the vertical direction and substantially parallel to the inner bottom surface in the concave portion 2 of the body 1. The upper surfaces 5a of the two protrusions 5 of the body 1 and the upper surfaces 20a, 30a of the first and second fixed contacts 20, 30 are spaced apart from the upper surfaces 20a, 30a of the fixed contacts 20, 30. They are arranged facing each other.

  Each of the inner wall of the recess 2 and each of the lower movable contacts 40 between the inner wall of the recess 2 of the body 1 and the outer peripheral edge of the annular portion 42 of the lower movable contact 40 and on both sides of each groove 4 of the body 1 in the depth direction. A gap (clearance) necessary for smooth operation of the lower movable contact 40 is provided between both side edges of the leg portion 42.

  As shown in FIGS. 10 and 11, the upper movable contact 50 is placed on the annular portion 41 of the lower movable contact 40, and the outer peripheral edge of the upper movable contact 50 is the outer peripheral portion of the annular portion 41 of the lower movable contact 40. And the upper movable portion 40 having an outer diameter substantially the same as the outer diameter of the annular portion 41 of the lower movable contact 40 so as to contact the first bent portion 42b or the base portion 42a of each leg portion 42 of the lower movable contact 40. It consists of a circular dome-shaped thin metal plate (circular dome-shaped leaf spring).

  The upper movable contact 50 has a circle that is smaller than the outer diameter of the annular portion 41 of the lower movable contact 40 and larger than the inner diameter of the annular portion 41 (the diameter of the central hole 41a) and concentric with the outer shape of the upper movable contact 50. An inflection portion 50a having a shape is provided, and an angle formed between the installation surface of the upper movable contact 50 (the upper surface of the annular portion 41 of the lower movable contact 40) and the upper movable contact 50 in a peripheral portion outside the inflection portion 50a. When the central part inside the inflection part 50a of the upper movable contact 50 is pushed down with a predetermined pressing force or more, it is formed so as to be reversed.

  As shown in FIGS. 3 and 4, the upper movable contact 50 is placed on the annular portion 41 of the lower movable contact 40 accommodated in the recess 2 of the body 1, and in this state, the outer peripheral edge of the upper movable contact 50. The upper movable contact 50 is brought into contact with or near the outer peripheral edge of the annular portion 41 of the lower movable contact 40 and the boundary between the first bent portion 42b and the base portion 42a of each leg portion 42 of the lower movable contact 40. The reversible central portion is disposed above the upper surface 10a of the central fixed contact 10 so as to be opposed to each other through a central hole 41a of the lower movable contact 40.

  The central portion of the upper movable contact 50 bulges upward from the upper surface of the recess 2 of the body 1.

  A gap (clearance) necessary for smooth vertical movement of the upper movable contact 50 is provided between the inner wall of the recess 2 of the body 1 and the outer peripheral edge of the upper movable contact 50.

  As shown in FIGS. 1 to 3, the insulating cover 60 is made of an insulating synthetic resin having a flexible shape and is formed on the upper portion of the body 21 so as to close the upper surface of the concave portion 2 of the body 1. Be placed.

  The insulating cover 60 may be an adhesive tape in which an adhesive is provided on the lower surface of a tape base material made of a rectangular sheet made of an insulating synthetic resin having flexibility. The adhesive tape is affixed to the central portion of the upper movable contact 50 bulging upward from the upper surface of the recess 2 of the body 1 with the central portion of the adhesive tape being attached to the concave portion 2 of the body 1. Is attached to a flat upper surface (the upper end surface of the side wall of the body 1) around the upper surface of the body 1 and fixed to the upper portion of the body 1.

  As shown in FIGS. 1 to 3, the metal cover 70 is provided with a circular center hole 71 in the center, and the center portion of the insulating cover 60 (the center portion of the upper movable contact 50 is swollen upward) from the center hole 71. It is a rectangular flat metal plate that covers the upper portion of the body 1 with the exposed circular dome).

  The metal cover 70 includes a pair of side edges corresponding to a pair of opposed outer walls of the body 1 in which the connection terminals 11, 21, 31 are disposed at both ends of the two sets of opposed side edges. A pair of first leg pieces 72 extending downward from the central portion of the body 1 and sandwiching a pair of opposed outer walls of the body 1, and a set of the body 1 in which the connection terminals 11, 21, 31 are not disposed And a pair of second leg pieces 73 extending downward from the remaining pair of side edges corresponding to the opposing outer walls of the body 1 and sandwiching the pair of opposing outer walls of the body 1. Two sets of first and second leg pieces 72 and 73 are positioned on the upper portion of the body 1.

  The metal cover 70 is substantially perpendicular to the inner side along the lower surface of the body 1 from both lower edge ends of each second leg piece 73 so that both side parts of each second leg piece 73 are formed in an L-shaped hook shape. The metal cover 70 is fixed to the upper portion of the body 1 with the upper surface and the lower surface of the body 1 sandwiched between the metal cover 70 and each of the locking claws 74. At this time, the insulating cover 60 is sandwiched and fixed between the upper surface of the body 1 and the metal cover 70.

  At least one of the first and second leg pieces 72 and 73 (four leg pieces) of the metal cover 70 is connected to a circuit board such as a device and used as a ground terminal.

  The metal cover 70 is made of one conductive metal plate.

  As described above, the push switch of the present embodiment is configured, and the operation thereof will be described with reference to FIGS. 3 and 12 to 14.

[First stage operation]
When the central portion of the upper movable contact 50 is pushed down via the insulating cover 60 from the state of no operation shown in FIG. 3, the outer peripheral edge of the annular portion 41 of the lower movable contact 40 at the outer peripheral portion of the upper movable contact 50. And the boundary between the first bent part 42b and the base part 42a of each leg part 42 of the lower movable contact 40 or its vicinity are pressed downward, and as shown in FIG. 12, the annular part 41 of the lower movable contact 40 The upper movable contact 50 remains in the form of a dome that bulges upward, and the annular portion 41 of the lower movable contact 40 and the upper movable contact 50 are pushed down integrally, and each leg of the lower movable contact 40 is The portion (substantially U-shaped leaf spring) 42 spreads outward while being simultaneously compressed and deformed, and the second bent portion 42d of each leg portion 42 is inside the recess 2 in the inner depth of each first groove portion 3 of the body 1. Hit the wall all at once.

  Subsequently, when the central portion of the upper movable contact 50 is further pushed down through the insulating cover 60 from the state shown in FIG. 12, as shown in FIG. Between the inner side wall of a certain recess 2 and the flat annular portion 41 of the lower movable contact 40, the folded plate (the base portion 42a, the first bent portion 42b, and the upper leg piece portion) of each leg portion 42 of the lower movable contact 40 42c) simultaneously reverses from the upper bulge shape to the lower bulge shape and jumps and buckles, the annular portion 41 of the lower movable contact 40 remains flat, and the upper movable contact 50 remains dome-shaped. Further, the annular portion 41 of the lower movable contact 40 and the upper movable contact 50 are integrally pushed down, and the upper surfaces 20a of the first and second peripheral fixed contacts 20 and 30 that the flat annular portion 41 of the lower movable contact 40 opposes. , 30a and contact. Then, the first and second peripheral fixed contacts 20 and 30 are electrically connected via the lower movable contact 40, and the first-stage switch is turned on.

  As described above, in the lower movable contact 40, the first stage operation without the inversion of the annular portion 41 is performed, and unlike the conventional lower movable contact (first stage) in which the center part is inverted in a dome shape with a central hole, An operation stroke can be secured by simultaneous compression deformation of each leg portion 42, and a click feeling can be given by simultaneous buckling of the folded plate of each leg portion 42. Further, each leg portion 42 which is smaller than the annular portion 41, and the folded plate which is a part of each leg portion 42 is further buckled, the first stage operation sound is reduced.

  Further, in the lower movable contact 40, after the folded plate of each leg portion 42 is buckled, when the annular portion 41 of the lower movable contact 40 and the upper movable contact 50 are moved down integrally, an extension portion (recovery auxiliary) The pressing portion 42h on the distal end side of the leaf spring 42g abuts on the root portion 42a and is pushed down, and the root portion 42a is urged upward by the extension portion 42g.

  The upper surface 5a of the two protrusions 5 of the body 1 is in a state where the annular portion 41 of the lower movable contact 40 abuts against and contacts the upper surfaces 20a, 30a of the first and second peripheral fixed contacts 20, 30 (first step). Are turned on), and are opposed to each other with a slight gap just below the two positions rotated approximately 90 from the contact positions of the annular portion 41 with the upper surfaces 20a, 30a of the first and second peripheral fixed contacts 20, 30 The two protrusions 5 of the body 1 regulate the inclination of the annular portion 41 of the lower movable contact 40, and the annular portion 41 of the lower movable contact 40 and the first and second peripheral fixed contacts 20, 30 And the contact reliability between the center portion of the upper movable contact 50 and the center fixed contact 10 described later.

[Second stage operation]
Then, when the central portion of the upper movable contact 50 is further pushed down through the insulating cover 60 from the state shown in FIG. 13, the installation surface of the upper movable contact 50 (the annular portion 41 of the lower movable contact 40) becomes the first and Since the second peripheral fixed contacts 20 and 30 abut against the upper surfaces 20a and 30a and are not pushed down any more, the center of the upper movable contact 50 is inverted as shown in FIG. The central fixed contact 10 and the first peripheral fixed contact 20 are connected to the lower movable contact 40 and the upper movable with a second click feeling by contacting the upper surface 10a of the central fixed contact 10 facing through the central hole 41a. Conduction is made through the contact 50, and the second-stage switch is turned on.

  As described above, the push switch of the present embodiment operates in two stages, with the lower movable contact 40 operating in the first stage and the upper movable contact 50 operating in the second inversion.

[Return operation]
When the central portion of the upper movable contact 50 is released from the state shown in FIG. 14, first, the central portion of the upper movable contact 60 is elastically returned to the original dome shape bulging upward, and is fixed to the center. The central portion of the upper movable contact 50 is separated upward from the upper surface 10a of the contact 10, the conduction between the central fixed contact 10 and the first peripheral fixed contact 20 is cut off, and the second-stage switch is turned off (see FIG. 13). Next, the folded plate of each leg portion 42 of the lower movable contact 40 is elastically restored to the original upper bulge shape, and the annular portion 41 of the lower movable contact 40 and the upper movable contact 50 are integrated with each other. When pushed up, the annular portion 41 of the lower movable contact 40 is separated upward from the upper surfaces 20a, 30a of the first and second peripheral fixed contacts 20, 30, and the first and second peripheral fixed contacts 20, 30 are electrically connected to each other. The first stage switch is turned off. (The state shown in FIG. 12) Finally, each leg portion 42 of the lower movable contact 40 is elastically restored to its original U-shape, and the annular portion 41 of the lower movable contact 40 and the upper movable contact 50 are further connected. It is pushed up integrally and returns to the state of no operation shown in FIG.

  At the time of the return operation, since the upward pressing force is applied to the base portion 42a of each leg portion 42, which is a connecting portion between the annular portion 41 of the lower movable contact 40 and each leg portion 42, the return is more reliably performed. can do.

  As described above, a preferred embodiment of the present invention has been described in the present embodiment, but the present invention is not limited thereto, and various modifications can be made without departing from the scope of the present invention. The lower movable contact of the present invention can also be used as one movable contact of a one-stage push switch.

DESCRIPTION OF SYMBOLS 1 Body 2 Recessed part 3 1st groove part 10 Center fixed contact 20 1st periphery fixed contact 30 2nd periphery fixed contact 40 Lower movable contact 41 Annular part 41a Center hole 41b, 41c Notch part pair 42 Leg part 42a Base part 42b 1st Bending part 42c Upper leg piece part 42d Second bending part 42e Lower leg piece part 42f Third bending part 42g Extension part 50 Upper movable contact G Gap

Claims (2)

  A box-shaped body made of an insulating resin having a recess having a plurality of grooves on the inner wall at the top opening, a center fixed contact disposed at the center of the inner bottom surface of the recess 2, and the outside of the center fixed contact A plurality of peripheral fixed contacts disposed in the recess, an annular portion that is accommodated in the concave portion and provided above the plurality of peripheral fixed contacts with a central hole, and extends from an outer peripheral edge of the annular portion. A lower movable contact made of a metal plate having a plurality of leg portions disposed corresponding to the plurality of groove portions, and placed on the annular portion, and an outer peripheral edge portion is always in contact with the annular portion and reversed. An upper movable contact made of an upwardly bulging dome-shaped metal plate disposed oppositely through the central hole above the central fixed contact; and the annular portion is formed in a flat plate shape. The first leg is bent from the outer peripheral edge of the annular part. An upper leg piece extending obliquely downward toward the inner bottom of the groove, and a predetermined distance from the upper leg piece to the front side of the inner wall of the recess at the inner depth of the groove. A lower leg piece portion extending below the upper leg piece portion is provided via a second bent portion arranged at an interval, and each leg portion forms a substantially U-shaped leaf spring. The lower leg piece is brought into contact with the inner bottom surface of the concave portion in the groove portion, and the annular portion and the upper movable contact mounted thereon are supported so as to be vertically movable. The outer peripheral edge is provided with a plurality of pairs of notch portions that are continuous with both side edges of the first bent portion of each leg portion, and each leg portion also has an inner pair of the notch portion pair in the annular portion. Each of the leg portions includes the root portion and the root portion. Each of the bent portion and the upper leg piece portion forms a buckled folding plate having the first bent portion as a top, and an outer peripheral edge portion of the annular portion on the outer peripheral edge portion of the upper movable contact, and A push switch characterized in that the first bent portion or the base portion of each leg is brought into contact.   Each of the legs is further provided with an extension that extends upwardly from the lower leg piece via the third bent part and has a distal end facing the lower side of the base. Each of the leg portions forms a cantilever-like return auxiliary leaf spring in the extension portion, and after the folded plate buckles, the distal end side of the extension portion abuts on the base portion and is pushed down. The push switch according to claim 1, wherein the base portion is biased upward by the extension portion.

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