JP7633090B2 - switch - Google Patents

Description

The present invention relates to a switch.

Various techniques are known for preventing damage to a switch caused by a pressing force applied in response to a pressing operation by an operator. For example, Patent Document 1 describes a switch that presses a switch mechanism including a rubber dome via a flexible pressing protrusion formed on a cover member and a drive member rotatably connected to a case. In the switch described in Patent Document 1, the switch mechanism is pressed via two members, the pressing protrusion and the drive member, so that the switch mechanism can be prevented from being damaged by excessive pressing force. In addition, in the switch described in Patent Document 1, the pressing position of the pressing protrusion in the vertical direction differs from the pressing position of the drive member in the vertical direction, so that the pressing force applied to the switch mechanism can be suppressed and excessive pressing force can be prevented from being applied to the switch mechanism.

Patent document 2 also describes a switch that is surrounded by a metallic rear cover member having a base that covers the rear side of the case and arms that extend forward from both ends of the base, and a metallic front cover member that covers the front of the case. The switch described in Patent Document 2 has improved resistance to pressure from the front by surrounding the case with a metallic cover member.

JP 2017-130277 A JP 2015-88448 A

However, in the switch described in Patent Document 1, the switch mechanism is pressed down via two members, the pressing protrusion and the drive member, so the stroke length when pressed is long and there is a risk of the click feeling being reduced due to the load of the pressing protrusion and the drive member. In addition, the switch described in Patent Document 1 has a pressing protrusion that extends in the pressing direction, and has two members, the pressing protrusion and the drive member, that press the switch mechanism, so it is not easy to reduce the size.

In addition, in the switch described in Patent Document 2, the case is surrounded by a cover member, so damage to the cover can be prevented. However, the movable contact, which is a contact spring, is subjected to a direct pressing force via the operating member, so there is a risk of damage when excessive pressing force is applied to the operating member.

The present invention aims to solve these problems by providing a switch that reduces the risk of damage to the contact spring when excessive pressing force is applied.

The switch according to the present invention has a base, a damper spring arranged on the surface of the base, a support base having a base supported by the damper spring, a first fixed contact arranged in the center of the surface of the base, and a second fixed contact arranged on the surface of the base outside the first fixed contact, a contact spring having a contact portion that contacts the second fixed contact and a bulge portion that bulges in the opposite direction to the surface of the base and arranged to contact the first fixed contact, a push plate arranged above the contact spring, and a plunger arranged on the underside of the push plate and having a protrusion that pushes the contact spring through a cover sheet, and the damper spring deforms in response to the plunger being pushed down, moving the support base towards the base.

Furthermore, in the switch according to the present invention, the base further has a pair of standing parts that stand up along the side surfaces of the support base from both ends in the short direction, the push plate is arranged to cover the pair of standing parts, and until the contact spring comes into contact with the first fixed contact when the top surface of the plunger is pressed down, the push plate is separated from the pair of standing parts, and after the contact spring comes into contact with the first fixed contact, the push plate preferably comes into contact with the pair of standing parts.

Furthermore, in the switch according to the present invention, it is preferable that the base and the damper spring are formed from a conductive material, and the support base further includes an insulating first leg and a second leg arranged on the outside of the damper spring, a first electrode arranged at the lower end of the first leg and electrically connected to the first fixed contact, a second electrode arranged at the lower end of the second leg and electrically connected to the second fixed contact, a first connection part arranged inside the first leg and connecting the first fixed contact and the first electrode, and a second connection part arranged inside the second leg and connecting the second fixed contact and the second electrode.

Furthermore, the switch according to the present invention has a push-down portion that is pushed down by a pusher, an elastic portion that holds the push-down portion movably in the direction of the plunger in response to the pushing force with which the pusher pushes down the push-down portion, a third electrode electrically connected to the push-down portion, and a fourth electrode electrically connected to the push-down portion, and preferably further has a conductive input spring supported by a support base.

Furthermore, in the switch according to the present invention, it is preferable that the support base is arranged outside the damper spring and further has insulating third and fourth legs with the third and fourth electrodes arranged at their respective lower ends, and the input spring further has a third connection portion arranged to pass through the third leg and connect the push-down portion and elastic portion to the third electrode, and a fourth connection portion arranged to pass through the fourth leg and connect the push-down portion and elastic portion to the fourth electrode.

Furthermore, in the switch according to the present invention, it is preferable that the input spring further has a first support portion arranged on the upper surface of the first leg, and a second support portion arranged on the upper surface of the second leg.

Furthermore, in the switch according to the present invention, the damper spring has a pair of bases arranged to be in contact with the surface of the base, a top arranged between the pair of bases and spaced apart from the surface of the base, and a pair of inclined portions connecting the pair of bases and the top, and it is preferable that the damper spring is supported by the tops.

Furthermore, in the switch according to the present invention, a pair of fastening holes into which a fastening member can be inserted is formed near both ends of the base, one of the pair of bases is formed with a fastening hole into which a fastening member can be inserted at a position corresponding to one of the pair of fastening holes, and the other of the pair of bases is preferably formed with a notch at a position corresponding to the other of the pair of fastening holes.

Furthermore, it is preferable that the switch according to the present invention further includes a cover sheet that covers the first fixed contact, the second fixed contact, and the contact spring.

The switch of the present invention can reduce the risk of the contact spring being damaged when excessive pressing force is applied.

1A is a perspective view (part 1) of a switch according to an embodiment, and FIG. 1B is a perspective view (part 2) of the switch shown in FIG. 1A is an exploded perspective view (part 1) of the switch shown in FIG. 1A, and FIG. 1B is an exploded perspective view (part 2) of the switch shown in FIG. 1A is a cross-sectional view taken along line AA in FIG. 1A, and FIG. 1B is a cross-sectional view taken along line BB in FIG. 1(a) is a perspective view of the base shown in FIG. 1(a), (b) is a front view of the base shown in FIG. 1(a), (c) is a plan view of the base shown in FIG. 1(a), and (d) is a side view of the base shown in FIG. 1(a). 1A is a perspective view of the damper spring shown in FIG. 1A, FIG. 1B is a plan view of the damper spring shown in FIG. 1A, and FIG. 1C is a side view of the damper spring shown in FIG. FIG. 2 is a perspective view of the lead frame shown in FIG. 1(a) is a plan view of the lead frame shown in FIG. 1(a), (b) is a bottom view of the lead frame shown in FIG. 1(a), (c) is a front view of the lead frame shown in FIG. 1(a), and (d) is a side view of the lead frame shown in FIG. 1(a). 7(b) is a perspective view of a pair of leads included in the lead frame shown in FIG. FIG. 3 is a perspective view of the first contact spring shown in FIG. 1(a) is a perspective view of the plunger shown in FIG. 1(a), (b) is a plan view of the plunger shown in FIG. 1(a), (c) is a bottom view of the plunger shown in FIG. 1(a), and (d) is a side view of the plunger shown in FIG. 1(a). FIG. 2 is a perspective view of the input spring shown in FIG. 1(a) shows the operation of the switch when the depressing portion of the input spring shown in FIG. 1(a) is pressed, (a) shows the state before the depressing portion of the input spring is pressed, (b) shows the state when the contact spring has performed the reversing operation, and (c) shows the state when the bottom surface of the plunger contacts the upper end of the upright portion of the base.

A switch according to one aspect of the present disclosure will be described below with reference to the drawings. However, please note that the technical scope of the present disclosure is not limited to these embodiments, but extends to the inventions described in the claims and their equivalents.

(Configuration and Function of Switch According to the Embodiment)
Fig. 1(a) is a perspective view (part 1) of a switch according to an embodiment, and Fig. 1(b) is a perspective view (part 2) of the switch shown in Fig. 1(a). Fig. 2(a) is an exploded perspective view (part 1) of the switch shown in Fig. 1(a), and Fig. 2(b) is an exploded perspective view (part 2) of the switch shown in Fig. 1(a). Fig. 3(a) is a cross-sectional view taken along line A-A shown in Fig. 1(a), and Fig. 3(b) is a cross-sectional view taken along line B-B shown in Fig. 1(a).

The switch 1 has a base 10, a damper spring 20, a lead frame 30, a contact spring 40, a cover sheet 50, a plunger 60, and an input spring 70, and is turned on when the input spring 70 is pressed by a pusher. The switch 1 also acquires a biometric information signal indicating biometric information such as the heart rate of the operator operating the switch 1 via the input spring 70, and outputs the acquired biometric information signal. The switch 1 is mounted on a flexible printed circuit board (Flexible Printed Circuits, FPC), and outputs a conduction signal indicating that the switch is on, and the biometric information signal to the FPC.

Figure 4(a) is a perspective view of the base 10, Figure 4(b) is a front view of the base 10, Figure 4(c) is a plan view of the base 10, and Figure 4(d) is a side view of the base 10.

The base 10 has a base base 11, a first fastening portion 12, a second fastening portion 13, a first rising portion 14, and a second rising portion 15. The base 10 is formed by punching and bending a steel material such as a cold-rolled steel plate (Steel Plate Cold Commercial, SPCC) using a press die or the like. In addition, carburizing and quenching may be performed to increase hardness.

The base 11 has a generally rectangular planar shape, with a first fastening portion 12 and a second fastening portion 13 disposed at both ends in the longitudinal direction, and a first upright portion 14 and a second upright portion 15 disposed at both ends in the lateral direction. The first fastening portion 12 and the second fastening portion 13 have a square planar shape, and are disposed at both ends in the longitudinal direction of the base 10. The first fastening portion 12 and the second fastening portion 13 each have a first fastening hole 16 and a second fastening hole 17 formed in the center, which are a pair of fastening holes into which a fastening member such as a screw can be inserted.

The first rising portion 14 and the second rising portion 15 each have a generally rectangular shape and are a pair of rising portions that rise from the center of both ends of the short side of the base 10 along the side of the lead frame 30. The upper ends of the first rising portion 14 and the second rising portion 15 are positioned below the lower surface of the plunger 60 and spaced apart from the lower surface of the plunger 60. The first rising portion 14 and the second rising portion 15 stop the movement of the plunger 60 toward the base 10, i.e., downward, by their upper ends coming into contact with the lower surface of the plunger 60 which moves toward the base 10 in response to being pressed by the operator.

Figure 5(a) is an oblique view of the damper spring 20, Figure 5(b) is a plan view of the damper spring 20, and Figure 5(c) is a side view of the damper spring 20.

The damper spring 20 is formed from a conductive plate material such as stainless steel (Steel Use Stainless, SUS), and has a first damper base 21, a second damper base 22, a damper top 23, a first inclined portion 24, and a second inclined portion 25. The damper spring 20 is disposed on the surface of the base 10 and supports the lead frame 30. The damper spring 20 deforms in response to the application of an excessive pressing force of 50 N or more, and moves the lead frame 30 toward the base 10.

The first damper base 21 and the second damper base 22 are a pair of bases arranged to be in contact with the surface of the base 10. The first damper base 21 has a square planar shape having the same area as the surface area of the first fastening portion 12, and a third fastening hole 26 is formed into which a fastening member to be inserted into the first fastening hole 16 can be inserted. The first damper base 21 is arranged overlapping the first fastening portion 12 so that its back surface faces the surface of the first fastening portion 12, and is fixed to the first fastening portion 12 by laser welding or the like. The second damper base 22 has a square planar shape having approximately the same area as the surface area of the second fastening portion 13. The second damper base 22 has a U-shaped notch 27 formed from the outer side of the second damper base 22 toward the inner side of the second damper base 22. The notch 27 is disposed at a position corresponding to the second fastening hole 17 formed in the second fastening portion 13, and can operate when an overload is applied. The first damper base 21 is fixed to the first fastening portion 12, but if the plate thickness of the damper spring 20 is thin, the second damper base 22 may be fixed to the second fastening portion 13 by laser welding in addition to the first damper base 21. Also, if fastening members such as pins are inserted and fixed into the first fastening hole 16 and the third fastening hole 26, the first damper base 21 does not need to be fixed to the first fastening portion 12.

The damper top 23 has a rectangular planar shape and is disposed in the center of the damper spring 20 at a distance from the surface of the base 10. The damper top 23 has a first engagement hole 28 and a second engagement hole 29 arranged in the short direction of the damper spring 20. The first engagement hole 28 and the second engagement hole 29 are engaged with the bottom surface of the lead frame 30.

The first inclined portion 24 and the second inclined portion 25 are a pair of inclined portions that connect the first damper base 21 and the second damper base 22, respectively, to the damper top 23. One end of the first inclined portion 24 is connected to the first damper base 21, and the other end of the first inclined portion 24 is connected to the damper top 23, and the first inclined portion 24 extends from the first damper base 21 toward the damper top 23 while inclining upward. One end of the second inclined portion 25 is connected to the second damper base 22, and the other end of the second inclined portion 25 is connected to the damper top 23, and the second inclined portion 25 extends from the second damper base 22 toward the damper top 23 while inclining upward.

Figure 6 is a perspective view of lead frame 30, Figure 7(a) is a plan view of lead frame 30, Figure 7(b) is a bottom view of lead frame 30, Figure 7(c) is a front view of lead frame 30, and Figure 7(d) is a side view of lead frame 30. Figure 8 is a perspective view of a pair of leads included in lead frame 30.

The lead frame 30 has a first fixed contact 31, a second fixed contact 32, a base 33, a first leg 34a, a second leg 34b, a third leg 34c, a fourth leg 34d, a first holding portion 35a, a second holding portion 35b, a first electrode 36, and a second electrode 37. The lead frame 30 is formed by integrally molding the first lead 38 and the second lead 39 into an engineering plastic such as high heat resistant polyamide by insert molding.

The first fixed contact 31 and the second fixed contact 32 are arranged inside a cylindrical housing 33a formed in the center of the surface of the base 33. The first fixed contact 31 is arranged in the center of the housing 33a, and the second fixed contact 32 is arranged along the outer edge of the housing 33a.

The base 33 has a substantially rectangular planar shape, with a housing portion 33a for housing the contact spring 40 formed on the front surface, and a first protrusion 33b and a second protrusion 33c formed on the back surface. In addition, a first leg 34a, a second leg 34b, a third leg 34c, and a fourth leg 34d are arranged at the four corners of the base 33. Each of the first protrusion 33b and the second protrusion 33c has a cylindrical shape and is arranged in the short direction of the base 33. The first protrusion 33b and the second protrusion 33c engage with the first engagement hole 28 and the second engagement hole 29 formed in the damper top 23 of the damper spring 20, so that the lead frame 30 is connected to and supported by the damper spring 20.

The first leg 34a, the second leg 34b, the third leg 34c, and the fourth leg 34d are disposed at the four corners of the base 33 and extend vertically. A first connection portion 85 that connects the first fixed contact 31 and the first electrode 36 is disposed inside the first leg 34a, and a second connection portion 87 that connects the second fixed contact 32 and the second electrode 37 is disposed inside the second leg 34b. The third leg 34c has a first through hole 34e, and the fourth leg 34d has a second through hole 34f. The third connection portion of the input spring 70 is disposed to pass through the first through hole 34e, and the fourth connection portion of the input spring 70 is disposed to pass through the second through hole 34f.

The first and second holding portions 35a and 35b are disposed opposite the longitudinal ends of the surface of the base 33. A first recess 35c and a second recess 35d are formed inside the first and second holding portions 35a and 35b. An input spring 70 is disposed on the upper surfaces of the first and second holding portions 35a and 35b, and a plunger 60 is disposed between the first and second holding portions 35a and 35b. The first and second recesses 35c and 35d engage with protrusions formed on the sides of the plunger 60, thereby preventing the plunger 60 from moving in the short direction of the switch 1 and falling off the lead frame 30.

The first electrode 36 is disposed on the underside of the first leg 34a and is electrically connected to the first fixed contact 31. The second electrode 37 is disposed on the underside of the second leg 34b and is electrically connected to the second fixed contact 32.

The first lead 38 has a first fixed contact 31, a first electrode 36, a first test electrode 81, a first arm 82, a second arm 83, a first lead base 84, and a first connection portion 85, and is enclosed inside the lead frame 30. The first lead 38 is formed by cutting and bending a conductive member such as phosphor bronze.

The first test electrode 81 is arranged to protrude from one side wall in the longitudinal direction of the lead frame 30, and a continuity test is performed between the first test electrode 81 and the first electrode 36 in an inspection process or the like during the manufacture of the switch 1. The first arm 82 connects the first fixed contact 31 and the first lead base 84, and the second arm 83 connects the first test electrode 81 and the first lead base 84. The first lead base 84 has a substantially rectangular planar shape and is enclosed in the base 33 of the lead frame 30 together with the first arm 82 and the second arm 83. The first connection portion 85 has one end connected to the first lead base 84 and the first electrode 36 arranged at the other end, and extends in the vertical direction. The first connection portion 85 is enclosed in the first leg portion 34a. The first connection portion 85 and the second connection portion 87 are arranged to sandwich the pressing portion of the input spring 70.

The second lead 39 has a second fixed contact 32, a second electrode 37, a second test electrode 86, and a second connection portion 87, and is enclosed inside the lead frame 30 together with the first lead 38. The second lead 39 is formed, like the first lead, by cutting and bending a conductive material such as phosphor bronze.

The second test electrode 86 is arranged on one side of the second fixed contact 32, a part of which is enclosed in the base 33, so as to protrude from the other longitudinal side wall of the lead frame 30, and a continuity test is performed between the second test electrode 86 and the second electrode 37 during an inspection process or the like during the manufacture of the switch 1. The second connection portion 87 has one end connected to the second fixed contact 32 and the second electrode 37 disposed on the other end, and extends in the vertical direction. The second connection portion 87 is enclosed in the second leg portion 34b.

The contact spring 40 has a first contact spring 41, a second contact spring 42, and a third contact spring 43. The first contact spring 41, the second contact spring 42, and the third contact spring 43 are formed from a thin metal plate having spring properties and have the same shape. The first contact spring 41, the second contact spring 42, and the third contact spring 43 are arranged overlapping the accommodation portion 33a of the lead frame 30.

Figure 9 is an oblique view of the first contact spring 41.

The first contact spring 41 is formed from a conductive plate material such as SUS, and has an outer edge portion 44 and a bulge portion 45. The outer edge portion 44 has a ring-like planar shape and is a contact portion that contacts the second fixed contact 32. The bulge portion 45 has a dome-like shape. The first contact spring 41 is arranged so that the bulge direction of the bulge portion 45 is opposite to the surface of the base 33, and the top portion 46 of the bulge portion 45 presses the first fixed contact 31 when the bulge portion 45 is inverted. The outer edge portion 44 is arranged along the entire outer edge of the bulge portion 45, but the outer edge portion 44 may have one or more notches formed therein.

When the top 46 is pressed down via the plunger 60 and a pressing force of about 3 N is applied, the bulge 45 reverses and the top 46 comes into contact with the first fixed contact 31. When the top 46 comes into contact with the first fixed contact 31, electrical continuity is established between the first electrode 36 and the second electrode 37 via the first fixed contact 31, the second fixed contact 32, and the contact spring 40, and the switch 1 is turned on.

When the pressing of the top 46 via the plunger 60 is completed, the bulge 45 returns to its original position and the top 46 moves away from the first fixed contact 31. As the top 46 moves away from the first fixed contact 31, the first electrode 36 and the second electrode 37 are no longer electrically conductive, and the switch 1 is turned off.

The configuration and function of the second contact spring 42 and the third contact spring 43 are the same as the configuration and function of the first contact spring 41, so a detailed description will be omitted here. By arranging the second contact spring 42 and the third contact spring 43 in addition to the first contact spring 41 and overlapping the first contact spring 41, the click feeling of the switch 1 is improved.

The cover sheet 50 is a sheet material made of a flexible synthetic resin such as polyimide, and is adhered to the entire surface of the base 33 including the housing portion 33a. By adhering the cover sheet 50 to the surface of the base 33, the first fixed contact 31, the second fixed contact 32, and the contact spring 40 housed in the housing portion 33a are covered by the cover sheet 50 and protected from the intrusion of moisture and foreign matter from the outside. The cover sheet 50 may be fixed by, for example, laser welding. In addition, the cover sheet 50 also has the function of electrically insulating the plunger 60 from the standing portion 14 and the standing portion 15 of the base 10 during an overload, and maintaining the electrical circuit of the biosignal input from the input spring 70 normally.

Figure 10(a) is a perspective view of plunger 60, Figure 10(b) is a plan view of plunger 60, Figure 10(c) is a bottom view of plunger 60, and Figure 10(d) is a side view of plunger 60.

The plunger 60 has a pusher plate 61, a first protrusion 62, a second protrusion 63, a first wall 64, a second wall 65, and a protrusion 66. The plunger 60 is formed by cutting a steel material such as SPCC that has been hardened by coining and then carburizing and quenching.

The push plate 61 has a generally rectangular planar shape, with a first protrusion 62 and a second protrusion 63 arranged at both ends in the short direction in the longitudinal center, and a first wall portion 64 and a second wall portion 65 arranged above both ends in the longitudinal direction.

When the plunger 60 is placed on the base 33 of the lead frame 30, the first protrusion 62 and the second protrusion 63 engage with the first recess 35c and the second recess 35d formed on the inside of the first holding portion 35a and the second holding portion 35b of the lead frame 30. The plunger 60 is prevented from falling off the lead frame 30 by the first protrusion 62 and the second protrusion 63 engaging with the first recess 35c and the second recess 35d.

A first receiving portion 67 and a second receiving portion 68 are formed on the inside of the first wall portion 64 and the second wall portion 65. Each of the first receiving portion 67 and the second receiving portion 68 has an arc-shaped planar shape and is disposed so as to face the outer edge of the input spring 70.

The protrusion 66 has a semicircular shape and is disposed on the underside of the push plate 61. When the push plate 61 is pushed down via the input spring 70, the contact spring 40 pushes down the protrusion 66 via the cover sheet 50. Although the protrusion 66 has a semicircular shape, the protrusion 66 may have a flat tip.

The plunger 60 is positioned so that the push-down plate 61 covers the first standing portion 14 and the second standing portion 15 of the base 10. Specifically, the plunger 60 is positioned so that the longitudinal end of the push-down plate 61 is located above the first standing portion 14 and the second standing portion 15.

Figure 11 is an oblique view of the input spring 70.

The input spring 70 has a pressing portion 71, a first elastic portion 72a, a second elastic portion 72b, a first branch portion 73a, a second branch portion 73b, a first support portion 74a, a second support portion 74b, a third connection portion 75, a fourth connection portion 76, a third electrode 77, and a fourth electrode 78. The input spring 70 is formed by punching and bending a low-load conductive material such as phosphor bronze.

The push-down portion 71 has a circular planar shape, is disposed at the center of the input spring 70, and is pushed down by the pusher. The first elastic portion 72a extends from the outer edge of the push-down portion 71 to the first branch portion 73a while curving along the outer edge of the push-down portion 71. The second elastic portion 72b extends from the opposite position of the outer edge of the push-down portion 71 to which the first elastic portion 72a is connected, while curving along the outer edge of the push-down portion 71 to the first branch portion 73a. The first elastic portion 72a and the second elastic portion 72b hold the push-down portion 71 movably in the direction of the push-down plate 61 of the plunger 60 in response to the pushing force with which the pusher pushes down the push-down portion 71.

The first branch 73a has a rectangular planar shape, and the first elastic part 72a is connected to the center of the inner side in the longitudinal direction. The second branch 73b has a rectangular planar shape like the first branch 73a, and the second elastic part 72b is connected to the center of the inner side in the longitudinal direction. The first support part 74a is arranged so that one end is connected to one end of the first branch 73a in the longitudinal direction and the other end is in contact with the upper surface of the first leg 34a of the lead frame 30. The second support part 74b is arranged so that one end is connected to one end of the second branch 73b in the longitudinal direction and the other end is in contact with the upper surface of the second leg 34b of the lead frame 30.

The third connection portion 75 has a thin plate shape extending vertically, one end of which is connected to the other end of the first support portion 74a, and the third electrode 77 is disposed at the other end. The fourth connection portion 76 has a thin plate shape extending vertically, one end of which is connected to the other end of the second support portion 74b, and the fourth electrode 78 is disposed at the other end. The third connection portion 75 and the fourth connection portion 76 are disposed on either side of the push-down portion 71.

The first elastic portion 72a, the first branch portion 73a, the first support portion 74a, and the third connection portion 75 are arranged in a point symmetrical manner with the second elastic portion 72b, the second branch portion 73b, the second support portion 74b, and the fourth connection portion 76, with the center point of the pressing portion 71 being the center of symmetry, when viewed in a plane.

When the body of the operator operating the switch 1, such as the fingertip, comes into contact with the conductive pusher, the input spring 70 outputs an electrical signal indicating the operator's biometric information, such as the operator's heart rate, from the third electrode 77 and the fourth electrode 78.

Figure 12 is a diagram showing the operation of the switch 1 when the depressing portion 71 of the input spring 70 is depressed. Figure 12(a) shows the state before the depressing portion 71 of the input spring 70 is depressed, Figure 12(b) shows the state in which the contact spring 40 has performed the reversing operation, and Figure 12(c) shows the state in which the bottom surface of the plunger 60 contacts the upper ends of the first upright portion 14 and the second upright portion 15 of the base 10. Each of Figures 12(a) to 12(c) is a cross-sectional view taken along line A-A in Figure 1(a).

A conductive pusher 100 is disposed above the switch 1, which pushes down the push-down portion 71 of the input spring 70. When an operator pushes down the pusher 100 with a finger or the like, the underside of the pusher 100 comes into contact with the push-down portion 71 of the input spring 70. When the pusher 100 comes into contact with the push-down portion 71 of the input spring 70, a bioinformation signal indicating the operator's bioinformation is output from the third electrode 77 and the fourth electrode 78.

When the pusher 100 is further pressed down, the pusher portion 71 of the input spring 70 moves in the push direction indicated by the arrow C while being supported by the first elastic portion 72a and the second elastic portion 72b, and comes into contact with the pusher plate 61 of the plunger 60. When the pusher 100 is further pressed down after coming into contact with the pusher plate 61 of the plunger 60, the plunger 60 moves from the initial position in the pusher direction together with the pusher portion 71 of the input spring 70.

When the plunger 60 moves in the pressing direction, the protrusion 66 of the plunger 60 presses the top 46 of the contact spring 40 through the cover sheet 50. In response to the protrusion 66 of the plunger 60 pressing the top of the contact spring 40, the bulge 45 of the contact spring 40 reverses and the top 46 of the first contact spring 41 comes into contact with the first fixed contact 31. When the top 46 of the first contact spring 41 comes into contact with the first fixed contact 31, electrical continuity is established between the first electrode 36 and the second electrode 37, and the switch 1 is turned on.

In addition, as the protrusion 66 of the plunger 60 presses down on the top of the contact spring 40, the damper top 23 of the damper spring 20 supporting the lead frame 30 having the housing portion 33a that houses the contact spring 40 moves in the pressing direction. As the damper top 23 of the damper spring 20 supporting the lead frame 30 moves in the pressing direction, the lead frame 30 moves in the pressing direction. When the switch 1 is turned on by a normal load such as 3N, the damper spring 20 bends, causing the lead frame 30 to move a distance of, for example, 9 μm.

When the pusher 100 is further pressed down, the lead frame 30 moves in the pressing direction in accordance with the movement of the damper top 23 of the damper spring 20 in response to the movement of the plunger 60 in the pressing direction. When the plunger 60 moves further in the pressing direction and the lower surface of the pressing plate 61 of the plunger 60 comes into contact with the upper ends of the first standing portion 14 and the second standing portion 15 of the base 10, the movement of the plunger 60 in the pressing direction stops. When the lower surface of the pressing plate 61 comes into contact with the upper ends of the first standing portion 14 and the second standing portion 15 due to an excessive load of, for example, 50 N, the damper spring 20 bends, causing the lead frame 30 to move a distance of, for example, 150 μm.

When the operator stops pressing the plunger 100, the pressing force applied via the plunger 100 and the pressing portion 71 of the input spring 70 becomes zero, and the damper top 23 of the damper spring 20 moves in the opposite direction to the pressing direction due to a restoring action. As the damper top 23 of the damper spring 20 moves, the lead frame 30 moves in the opposite direction to the pressing direction and returns to its initial position. In addition, the pressing force becomes zero, and the contact spring 40, which was performing a reversing action, performs a restoring action, and the plunger 60 moves in the opposite direction to the pressing direction and returns to its initial position.

(Functions and Effects of the Switch According to the Embodiment)
When an excessive pressing force is applied to the switch 1, the lead frame 30 housing the contact spring 40 moves in the pressing direction, so there is little risk of the contact spring 40 being damaged by application of excessive pressing force.

In addition, in the switch 1, when the plunger 60 moves a predetermined distance in the pressing direction, the bottom surface of the plunger 60 comes into contact with the upper ends of the first and second standing portions 14 and 15 of the base 10, and the movement of the plunger 60 in the pressing direction stops. In the switch 1, the first and second standing portions 14 and 15 regulate the movement of the plunger 60 in the pressing direction, so that it is possible to prevent the application of excessive pressing force to the contact spring 40 without using a large spring as the damper spring 20 to increase the movement distance of the lead frame 30.

In addition, in the damper spring 20, the first rising portion 14 and the second rising portion 15 restrict the movement of the plunger 60 in the pressing direction, so there is no need to use a large spring as the damper spring 20 that has durability against a very large pressing force of, for example, 100 N or more. Because there is no need to use a large spring as the damper spring 20, the switch 1 can be made smaller.

In addition, in the switch 1, the first connection portion 85, the second connection portion 87, the third connection portion 75, and the fourth connection portion 76 are disposed inside the insulating first leg portion 34a to the fourth leg portion 34d, so that the distance between the base 10 and the damper spring 20, which are made of a conductive material, can be shortened. The switch 1 can be made smaller by shortening the distance between the first connection portion 85, the second connection portion 87, the third connection portion 75, and the fourth connection portion 76, and the base 10 and the damper spring 20.

In addition, in the switch 1, the first support portion 74a and the second support portion 74b of the input spring 70 are arranged on the upper surfaces of the first leg portion 34a and the second leg portion 34b, in which the first connection portion 85 and the second connection portion 87 are arranged, so that the horizontal area can be reduced.

In addition, in switch 1, the third connection portion 75 and the fourth connection portion 76 are arranged on either side of the push-down portion 71 so as to be point-symmetrical with respect to the center of the push-down portion 71, so that the electrical characteristics of the bioinformation signals output from the third electrode 77 and the fourth electrode 78 are the same.

(Modification of the Switch According to the Embodiment)
Although the switch 1 has a single damper spring 20, the switch according to the embodiment may have two or more damper springs with different elastic forces arranged in a superimposed manner. For example, the switch according to the embodiment can suppress the propagation of vibrations generated by pressing the switch to the FPC by arranging a damper spring with a small elastic force superimposed above a damper spring with a large elastic force arranged on the surface of the base.

The switch according to the embodiment may also have a conductive elastic member such as a spring below the first electrode 36, the second electrode 37, the third electrode 77, and the fourth electrode 78. By having a conductive elastic member below the first electrode 36, the second electrode 37, the third electrode 77, and the fourth electrode 78, the switch according to the embodiment can suppress the propagation of vibrations caused by being pressed down to the FPC.

In the switch 1, the damper spring 20 is a leaf spring that supports the lead frame 30 with its top connected to its base via an inclined portion, but in the switch according to the embodiment, the damper spring may be another elastic body such as a coil spring or a disc spring.

In addition, in the switch 1, the contact spring 40 is accommodated in the accommodation portion 33a formed in the lead frame 30, but in the switch according to the embodiment, the accommodation member that accommodates the contact spring 40 may be formed from a substrate and a frame material.

In addition, the switch 1 has an input spring 70 that acquires biometric information of the operator, but in the switch according to the embodiment, if the biometric information of the operator is not acquired, the input spring 70 may be omitted.

1 Switch 10 Base 20 Damper spring 30 Lead frame (support)
40 contact spring 50 cover sheet 60 plunger 70 input spring

Claims (9)

With the base,
A damper spring disposed on a surface of the base;
a support base including a base supported by the damper spring, a first fixed contact disposed at a center of a surface of the base, and a second fixed contact disposed outside the first fixed contact on the surface of the base;
a contact spring having a contact portion that contacts the second fixed contact and a bulge portion that bulges in a direction opposite to the surface of the base, the contact spring being disposed so as to contact the first fixed contact;

a pusher plate disposed above the contact spring, and a plunger disposed on a lower surface of the pusher plate and having a protrusion for pushing down the contact spring;
The damper spring deforms in response to the plunger being pressed down, and moves the support base toward the base.
A switch characterized by: The base further includes a pair of upright portions extending from both ends in a short side direction along the side surfaces of the support base,
The pressing plate is disposed so as to cover the pair of upright portions,
The push-down plate is separated from the pair of upright portions while the upper surface of the plunger is pushed down and the contact spring comes into contact with the first fixed contact.
The switch according to claim 1 , wherein the depression plate contacts the pair of upright portions after the contact spring contacts the first fixed contact. the base and the damper spring are formed of a conductive material;
The support base is
an insulating first leg portion and an insulating second leg portion disposed on the outer side of the damper spring;
a first electrode disposed at a lower end of the first leg and electrically connected to the first fixed contact;
a second electrode disposed at a lower end of the second leg and electrically connected to the second fixed contact;
a first connection portion disposed inside the first leg portion and connecting the first fixed contact and a first electrode;
a second connection portion disposed inside the second leg portion and connecting the second fixed contact and a second electrode;
The switch of claim 1 or 2, further comprising: A pressing part that is pressed by a pressing member;
an elastic portion that holds the depression portion so as to be movable toward the plunger in response to a pressing force applied by a pusher to press the depression portion;
A third electrode electrically connected to the depression portion;
a fourth electrode electrically connected to the depression portion,
4. The switch of claim 3, further comprising a conductive input spring supported by the support base. the support base further includes an insulating third leg portion and an insulating fourth leg portion, the third leg portion and the fourth leg portion being disposed on the outer side of the damper spring and having the third electrode and the fourth electrode disposed on the lower end thereof,
The input spring is
a third connection portion that is disposed through the third leg portion and connects the push-down portion and the elastic portion to the third electrode;
a fourth connection portion that is disposed through the fourth leg portion and connects the push-down portion and the elastic portion to the fourth electrode;
The switch of claim 4 further comprising: The switch of claim 5, wherein the input spring further includes a first support portion disposed on an upper surface of the first leg and a second support portion disposed on an upper surface of the second leg. The damper spring is
A pair of base portions arranged in contact with a surface of the base;
a top portion disposed between the pair of base portions and spaced apart from a surface of the base;
a pair of inclined portions connecting the pair of base portions and the top portion;
The switch of any one of claims 1 to 6, wherein the damper spring is supported on the top portion. A pair of fastening holes into which fastening members can be inserted are formed near both ends of the base,
one of the pair of base portions is formed with a fastening hole into which a fastening member can be inserted at a position corresponding to one of the pair of fastening holes;
The switch according to claim 7 , wherein the other of the pair of base portions is formed with a notch at a position corresponding to the other of the pair of fastening holes. The switch according to any one of claims 1 to 8, further comprising a cover sheet that covers the first fixed contact, the second fixed contact, and the contact spring.

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