JP5053419B2 - Seat switch - Google Patents

Description

  The present invention relates to a sheet switch that is pressed by a user.

FIG. 13 shows the configuration of a conventional seat switch. The sheet switch 100 includes a contact sheet 101, a metal dome 102 placed on the contact sheet 101, and a surface sheet 103 that covers the contact sheet 101 and the metal dome 102. The metal dome 102 has flexibility. The top sheet 103 is formed by stacking the dome spacer 104 and the dome holding member 1.
It is placed on the contact sheet 101 via 05.

The contact sheet 101 includes a pair of sheets 106 facing each other, contacts 107 provided on the opposing surfaces of the sheets 106, and contact spacers 108 for separating the contacts 107 from each other. The metal dome 102 is placed at a position corresponding to the contact 107 on the contact sheet 101 (see, for example, Patent Documents 1 to 3).

The dome holding member 105 has an opening into which the top portion of the metal dome 102 and the peripheral portion thereof are fitted, and elastically presses the metal dome 102 against the contact sheet 101 at the edge of the opening. When the top sheet 103 is pushed down, the metal dome 102 is deformed and presses the contact sheet 101 to electrically connect the contact 107.

The top sheet 103 is normally pressed by the user's finger belly, and the metal dome 102 operates without problems even if it is pressed several hundred thousand to one million times, assuming that the finger is pressed by the finger. Durability has been imparted.

However, when pressed down with a thin and hard tip such as a key or pen, the metal dome 102
As a result, the metal dome 102 is locally distorted or metal fatigue is increased. Therefore, when such pressing is repeated, the metal dome 102 maintains the inverted state by several hundred to several thousand pressing operations, and finally the contact sheet 101 remains pressed. Therefore, the contact 107 is always in a conductive state. In such a state, the function as a switch cannot be maintained. For example, when the seat switch 100 is used as a password input key of a device that manages entry / exit, the operation is performed by an unspecified number of people, and the number of operations increases, so that the above problem is likely to occur.

Japanese Utility Model Publication No. 7-1545 JP 2004-14143 A Japanese Utility Model Publication No. 6-50193

The present invention has been made in order to solve the above-described conventional problems, and can improve the durability against the pressing operation. Also, when the switch on the top sheet is pressed, a good operation feeling is obtained. It aims at providing the sheet switch obtained.

In order to achieve the above-mentioned object, the invention according to claim 1 is mounted at a position corresponding to the contact on the contact sheet, in which a contact is provided on each facing surface of a pair of sheets facing each other. A metal member having a dome shape and a surface sheet covering the contact sheet and the metal member, and when the surface sheet is pressed down, the metal member is deformed to press the contact sheet, in sheet switch for electrically connecting said contact between the metal member and the topsheet, the protective plate for protecting the metal member by dispersing the pressing force to the metal member is provided, the protection the plate is formed a slit portion, the slit portion is in a circular shape or square shape of the protective plate in plan view, it is formed at least one or more positions with a substantially T-shaped with the exception of the vicinity of the center of the protective plate Is shall.

According to the switch sheet according to the present invention, even if the top sheet is pressed down by a thin and hard tip such as a key or a pen, the metal member is pressed through the protective plate, so that the pressing force is applied by the protective plate. Dispersed, it is possible to prevent local distortion and metal fatigue of the metal member due to concentration of the pressing force. Therefore, the durability of the metal member against the pressing operation is improved.

According to the seat switch of the present invention, the protective plate is formed with a slit portion having a substantially T-shape or spiral shape, so that the operation force when the switch is pressed is reduced while maintaining the durability of the seat switch. The operational feeling can also be improved.

According to the sheet switch of the present invention, when the surface sheet is pressed down, the convex portion of the protective plate presses the top of the metal member, so that the pressing force is evenly distributed around the pressing portion, and thus the above-mentioned The effect is definitely obtained.

According to the sheet switch of the present invention, even if the top sheet is biased and pushed down, the protective plate is bent by the action of the leaf spring and lowered as a whole. The above effect can be obtained with certainty.

Sectional drawing which shows the sheet switch which concerns on the 1st Embodiment of this invention. Sectional drawing which shows a mode when a part of said sheet switch is pushed down. The front view which shows the information input device provided with the said sheet switch. Sectional drawing which shows the sheet switch which concerns on the modification 1 of the said embodiment. Sectional drawing which shows the sheet switch which concerns on the modification 2 different from the above. (A) And (b) is a top view of a protection board. (A)-(f) is a top view of a protection board. (A) is sectional drawing of the sheet switch which concerns on the modification 3, (b) is a top view of a protection board. (A) is sectional drawing of the sheet switch which concerns on the modification 4, (b) is a top view of a protection board, (c) is a top view of the other example of a protection board. (A) is sectional drawing of the sheet switch which concerns on the modification 5, (b) is a top view of a protection board sheet, (c) is a top view of the protection board sheet which has a slit part. (A) is sectional drawing of the sheet switch which concerns on the modification 6, (b) is a top view of a protection board sheet, (c) is a top view of the protection board sheet which has a slit part. (A) is sectional drawing of the sheet switch which concerns on the modification 7, (b) is a top view of a protection board sheet, (c) is a top view of the protection board sheet which has a slit part. Sectional drawing which shows the conventional sheet switch.

Hereinafter, a sheet switch according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows the configuration of the seat switch of this embodiment. The sheet switch 1 includes a contact sheet 2, a metal dome 3 (dome-shaped metal member) placed on the contact sheet 2,
A surface sheet 4 covering the contact sheet 2 and the metal dome 3 and a protection plate 5 for protecting the metal dome 3 are provided. The metal dome 3 has flexibility. The top sheet 4 is placed on the contact sheet 2 via the stacked dome spacer 6 and dome holding member 7, and has a key portion 4 a at a position corresponding to the metal dome 3. The protection plate 5 is disposed between the metal dome 3 and the top sheet 4.

The contact sheet 2 includes a pair of sheets 21 and 22 facing each other, an upper contact 23 and a lower contact 24 (contacts) provided on opposite surfaces of the sheets 21 and 22, an upper contact 23 and a lower contact 24, respectively.
And a contact spacer 25 for separating the two. The upper contact 23 and the lower contact 24 face each other, and the contact spacer 25 is inserted between the sheet 21 and the sheet 22. The metal dome 3 is placed at a position corresponding to the upper contact 23 and the lower contact 24 on the contact sheet 2. The size of the metal dome 3 in plan view is determined according to the size of the key portion 4a. The key portion 4a has numbers, symbols, characters, etc. printed on its surface. It is desirable that the key portion 4a has a shape that rises more than its surroundings so that the user can easily see it.

The protective plate 5 is, for example, a circular or square flat plate in plan view for dispersing the pressing force to the metal dome 3 to protect the metal dome 3, and is disposed at a position corresponding to the metal dome 3. . This flat plate is a metal plate such as a SUS (Stainless Steel) plate, or PET (Pol
yethylene Terephthalate) or the like, and is bonded to the back surface of the key portion 4a by an adhesive member or the like. The flat plate has a size and a plan view shape corresponding to the key portion 4a, and is preferably larger than the metal dome 3 in the plan view. The protection plate 5 has a gap of a predetermined dimension between the protection plate 5 and the top portion 3 a of the metal dome 3.

Since the protective plate 5 becomes rigid as the thickness increases, the protective effect increases. However, if the protective plate 5 becomes too thick, the thickness of the sheet switch 1 increases. Moreover, the metal dome 3 pressed by the protective plate 5 may be deformed to the extent that it cannot be restored by its restoring force, or may be inverted and remain in that state. Therefore, the thickness of the protective plate 5 is the load, outer diameter,
It is desirable to be determined according to the stroke amount (the amount of change in height due to pressing), the material, or the thickness. The same applies to the shape, size and material of the protective plate 5.

The dome spacer 6 has a hole having a diameter equal to or larger than the outer diameter of the metal dome 3, and the metal dome 3 is accommodated in the hole. The dome holding member 7 has an opening at a position corresponding to the hole, and the top portion 3a of the metal dome 3 and its peripheral portion protrude from the opening. The dome presser member 7 elastically presses the metal dome 3 against the contact sheet 2 with the edge of the opening. The protective plate 5 is dimensioned so as not to enter the opening in a state where the protective plate 5 is pressed down and bent.

FIG. 2 shows a state of each part when a part of the sheet switch 1 is pushed down. Key part 4a
Is pushed down, the protective plate 5 presses the metal dome 3, whereby the metal dome 3 is bent and deformed, the contact sheet 2 is pressed, and the upper contact 23 and the lower contact 24 are brought into contact with each other to electrically To conduct.

FIG. 3 shows an information input device to which the sheet switch 1 is applied. In the information input device 10, the sheet switch 1 is arranged and arranged on the front surface of the device as a numeric keypad for information input operation. The information input device 10 is a device such as a non-contact type IC card reader or a fingerprint reader for inputting a password or the like in the security system, for example. The application example of the sheet switch 1 is not limited to the above.

In the sheet switch 1 configured as described above, the metal dome 3 is pressed through the protective plate 5 even if the top sheet 4 is pressed down by a thin and hard tip such as a key or a pen. Therefore, the pressing force is dispersed by the protective plate 5, and local distortion and metal fatigue of the metal dome 3 due to concentration of the pressing force can be prevented. For this reason, it is possible to improve the durability of the metal dome 3 against the pressing operation.

(Modification 1)
FIG. 4 shows a seat switch according to the first modification of the above embodiment. This seat switch 1
The protective plate 5 has a spherical convex portion 5 a protruding toward the metal dome 3. The convex part 5a is arrange | positioned in the position corresponding to the top part 3a of the metal dome 3, is facing the top part 3a, and has a clearance gap of the predetermined dimension between the convex part 5a and the top part 3a. The convex portion 5a is formed integrally with the protective plate 5 and is made of the same material. The shape of the convex part 5a is not limited to the above.

In this modified example, when the topsheet 4 is pushed down, the convex portion 5a of the protective plate 5 reliably pushes the top portion 3a of the metal dome 3, so that the pressing force is distributed evenly around the pressing portion. . Therefore, local distortion and metal fatigue of the metal dome 3 can be reliably prevented.

Further, since the peripheral portion of the top portion 3a of the metal dome 3 is bent and deformed in accordance with the pressing operation, when the deformation is repeated, metal fatigue is accumulated. The pressing can be surely avoided, and therefore the durability of the metal dome 3 is improved.

(Modification 2)
FIG. 5 shows a seat switch according to a second modification different from the above. The protection plate 5 of the seat switch 1 according to the second modification is configured by a leaf spring interposed between the top sheet 5 and the contact sheet 2.

The protection plate 5 has a fixed portion 5b fixed at one end thereof so as to be a fulcrum for bending the leaf spring, and has a movable portion 5c bent at the other end using the fixed portion 5b as a fulcrum. The fixing portion 5b is sandwiched and fixed between the top sheet 4 and the dome pressing member 7. The movable part 5c is a key part 4
It exists between a and the metal dome 3, and it does not need to be adhere | attached on the back surface of the key part 4a. The movable portion 5c includes the convex portion 5a and a bent portion 5d that is bent so that the movable portion 5c is along the shape of the back surface of the key 4a. The bent portion 5d has a substantially step shape inclined upward from the fixed portion 5b toward the movable portion 5c. When the top sheet 4 is pressed down, the movable portion 5c bends in the direction of the metal dome 3 with the fixed portion 5b as a fulcrum.

Further, when the plate spring is a resin molded product, the protective plate 5 is for securing moldability and rigidity.
The thickness is preferably about 1 [mm] or more, for example.

In the second modification, even if the top sheet 4 is biased and pushed down, the movable portion 5c is bent and lowered as a whole by the action of the leaf spring, so that it is not pushed down. Therefore, the movable part 5c can push the top part 3a of the metal dome 3 in a substantially vertical direction, and the pressing force can be evenly distributed around the pressing part. Therefore, the durability of the metal dome 3 is improved.

Further, the protective plate 5 shown in FIGS. 1, 4 and 5 (the portion corresponding to the metal dome 3 or the key portion 4a in the case of FIG. 5) is a flat plate as shown in FIG. When the switch is pressed, it is difficult to bend, the load (pressing pressure) when the switch is pressed increases, and the operation feeling (click feeling) of the user may be reduced.

Therefore, as shown in FIG. 7, slits 5e, 5f or 5g are formed in the protective plate 5 of the sheet switch 1. The slit portion is a cut or gap formed in the protective plate 5. By forming this slit portion in the protective plate 5, the operation force of the user when the switch is pressed while maintaining the durability of the protective plate 5. Can be reduced to improve the operational feel.

The slit portions 5e shown in FIGS. 7A, 7C, and 7D are formed in a substantially T shape at the four corners except for the vicinity of the center of the circular or square protection plate 5 in plan view. The slit portion 5f shown in FIGS. 7 (b) and (f) is formed in a spiral shape except for the vicinity of the center of the circular or square protection plate 5 in plan view, and the slit portion 5g shown in FIG. It is formed in a substantially linear shape except for the vicinity of the center of the circular or quadrangular protective plate 5 in plan view. In addition, the shape and width of the slit portion are not limited to the shape and width shown in the figure, and can be arbitrarily set. However, if the shape, position, and width of the slit portion are not appropriate, the metal dome 3 may not be properly protected, and the protection plate 5 may be broken.

The protective plate 5 shown in FIGS. 6 and 7 is usually manufactured by an etching method using chemicals or the like.
In addition, press working using metal molds, NC turret punch press machining with a punch on the upper side and a mold on the lower side to drill a metal plate or resin plate at a predetermined position with a pre-made program, Although pressure processing using a laser, a water jet, or the like is possible, in these cases, burring, warping, and burning of the protective plate 5 may not be prevented, and narrow width processing may not be possible.

(Modification 3)
FIG. 8 shows a seat switch 1 according to Modification 3 of the above embodiment. In the sheet switch 1 according to the third modification, the sheet switch 1 fixes the protective plate 5 at the time of manufacture.
As shown in (a) and (b), a pressure-sensitive adhesive 8 or a pressure-sensitive adhesive sheet 8 such as a double-sided tape is attached to the entire surface of the protective plate 5 on the surface sheet 4 side. With this configuration, the protective plate 5 can be reliably adhered to the top sheet 4 using the adhesive 8, and the protective plate 5 can be reliably fixed in the manufacturing process.

(Modification 4)
FIG. 9 shows a seat switch 1 according to Modification 4 of the above embodiment. In addition, the said modification 3
In the case of the sheet switch 1 according to the above, when the area of the adhesive 8 is large, the protective plate 5 is fixed as a whole, and when the switch is pressed, it is difficult to bend, and the operation feeling may be deteriorated. And
Usually, the area where the adhesive 8 is attached to the protective plate 5 is smaller when the switch is pressed.
Since the movement of the robot becomes relatively free, the operation feeling is improved.

Therefore, in the sheet switch 1 according to the fourth modification, as shown in FIG.
The adhesive 8 is pasted only near the center of the top sheet 4 side. In this case, the pressure-sensitive adhesive 8 is small, and positioning when the pressure-sensitive adhesive 8 is attached to the central portion of the protective plate 5 becomes difficult. Therefore, FIG.
When slits 5e and positioning holes 9 as shown in b) and (c) are formed in the protective plate 5, and the adhesive 8 is attached to the central portion of the protective plate 5, these slit portions 5e and positioning holes By sticking the adhesive 8 on the basis of 9, it becomes possible to facilitate the positioning of the adhesive 8 on the protective plate 5. When the protective plate 5 is formed of a PET sheet or the like, the PET sheet is originally soft and even if the adhesive 8 is attached to the entire surface of the protective plate 5 on the surface sheet 4 side, there is no problem with respect to the operation feeling.

(Modification 5)
FIG. 10 shows a seat switch 1 according to Modification 5 of the above embodiment. As shown in FIGS. 10B and 10C, the sheet switch 1 according to the fifth modification is provided corresponding to the plurality of contacts and the metal dome 3 that are arranged in a row of the contact sheets 2. A protective plate sheet 11 made of a single plate spring having a plurality of protective plates 5 corresponding to the movable portion 5c and a frame portion 5b (fixed portion) integrally connecting them is used. The protective plate sheet 11 is formed with a bent portion 5d along the shape of the switch of the surface sheet 4, and the bent portion 5d serves as a portion connecting the frame portion 5b and each protective plate 5.

A protective plate sheet 11 in which no slit portion is formed in the protective plate 5 shown in FIG.
The protective plate sheet 11 that forms the slit portion 5e in the protective plate 5 shown in (c) is manufactured, for example, by forming a bent portion 5d using a mold after forming a shape by etching. Note that press working using a mold, NC turret punch press working, pressure working using a laser or a water jet, and the like can be used, but in this case, the protective plate 5 may be warped and burned.

(Modification 6)
FIG. 11 shows a seat switch 1 according to Modification 6 of the above embodiment. In the sheet switch 1 according to the sixth modified example, the protective plate 5 having a circular shape or a square shape in plan view manufactured in advance by an etching method is associated with a plurality of contact points and positions corresponding to the metal members. The protective plate sheet 12 affixed on this sheet is used. The sheet switch 1 can be easily obtained by superposing the protective plate sheet 12 on the spacer sheet 13 provided to eliminate interference between the protective plate sheet 12 and the metal dome 3 and superposing the top sheet 4 on the protective plate sheet 12. Can be produced.

(Modification 7)
FIG. 12 shows a seat switch 1 according to Modification 7 of the above embodiment. The sheet switch 1 according to the modified example 7 includes a plurality of contact plates provided in a row of contact sheets 2 and a plurality of protection plates 5 corresponding to movable parts provided corresponding to the metal domes 3 and these. A protective plate sheet 14 composed of a single leaf spring having a frame portion 5b (fixed portion) that integrally connects the two is used. In the sheet switch 1, the protective plate sheet 14 is overlaid on the spacer sheet 13 provided to eliminate interference between the protective plate sheet 14 and the metal dome 3, and the surface sheet 4 is placed on the protective plate sheet 14.
It can be easily manufactured by stacking. Further, in the sheet switch 1 according to the modified example 7, the sheet switch 1 shown in FIG.
The bent portion 5d as shown in 0 is not formed.

In addition, this invention is not limited to the structure of said embodiment and modification, Various deformation | transformation are possible according to a use purpose. For example, the shape of the key portion 4a in plan view may be substantially circular, and that of the protective plate 5 may be the same shape. Further, the dome spacer 6 and the dome pressing member 7 can be omitted if the surface sheet 4 and / or the contact sheet 2 are provided with their functional configurations. Further, in the modification shown in FIG. 5, the protection plate 5 may be a plate spring that does not have the convex portion 5a, or a flat plate spring that does not have the bent portion 5d. Absent.

1 Sheet switch 2 Contact sheet 23 Upper contact (constitutes contact)
24 Lower contact (constitutes contact)
3 Metal Dome (Metal member)
4 Surface sheet 5 Protection plate 5a Convex part 5d Bending part 5e, 5f, 5g Slit part 6 Dome spacer 7 Dome holding member 8 Adhesive (double-sided tape)
9 Positioning holes 11, 12, 14 Protection plate sheet 13 Spacer sheet

Claims (9)

A contact sheet in which contacts are provided on respective opposing surfaces of a pair of sheets facing each other; a dome-shaped metal member placed at a position corresponding to the contact on the contact sheet; and the contact sheet And a sheet switch that covers the metal member, and when the surface sheet is pressed down, the metal member is deformed to press the contact sheet and electrically connect the contact,
A protective plate for protecting the metal member by dispersing the pressing force to the metal member is provided between the metal member and the surface sheet ,
A slit portion is formed in the protective plate,
The sheet switch is characterized in that at least one or more slits are formed in a substantially T shape except for the vicinity of the center of the protective plate in the circular or square protective plate in plan view . The slit portion is in a circular shape or square shape of the protective plate in plan view, the sheet switch according to claim 1, wherein the formed except near the center of the protective plate in a spiral shape. The sheet switch according to any one of claims 1 to 2 , wherein an adhesive or double-sided tape that adheres to the surface sheet is attached to the surface sheet side of the protective plate. The sheet switch according to any one of claims 1 to 3 , wherein the protective plate has a convex portion that protrudes toward the metal member at a position corresponding to a top portion of the metal member. . The sheet switch according to any one of claims 1 to 4 , wherein the protection plate is configured by a sheet-like leaf spring interposed between the top sheet and the contact sheet. The sheet-like leaf spring has a plurality of protective plate portions provided corresponding to the contact points and metal members provided side by side in a row, and a frame portion integrally connecting them. The sheet switch according to claim 5 . The sheet switch according to claim 6 , wherein the leaf spring is formed with a bent portion along a shape of the switch of the face sheet. A plurality of the contact points and the metal members are provided in a line, and a plurality of protective plates provided at positions corresponding to the plurality of contact points and the metal members are pasted on one sheet. The seat switch according to any one of claims 1 to 4 , wherein The sheet switch according to claim 8 , wherein a spacer for preventing the metal member from interfering with the sheet is disposed on a surface on the contact sheet side of the sheet to which the protection plate is attached.

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