JP2002056748A - Sheet having movable contact point and sheet switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet having a movable contact point and a structure of a sheet switch wherein countermeasures for cost saving are taken by reducing the number of parts, and operation feeling is made superior by preventing an outer peripheral end part of a movable contact point and the sheet to collide, and wherein invasion of dust is prevented and high contact reliability is obtained even when the sheet having the movable contact point and the movable contact point of the sheet switch are pressed down. SOLUTION: This is equipped with a sheet 1 made by insulating film and a movable contact point 3 having a mounted dome-shaped swelling part whose upper face is covered by this sheet 1, and at the sheet 1, a housing part 1a to protrude to an upper face side is formed, and the swelling part of the movable contact point 3 is made to be pasted to an inner face of this housing part 1a by an adhesive 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat with a movable contact used for an operation panel of various electronic devices and a seat switch using the same.

[0002]

2. Description of the Related Art FIGS. 5 to 8 show a conventional structure of a sheet with movable contacts and a sheet switch. 5 is an exploded perspective view showing a sheet with movable contacts with spacers, FIG. 6 is a sectional view showing the same sheet switch,
7 and 8 are a plan view and a sectional view showing a sheet with movable contacts and a sheet switch having a single sheet structure.

In FIG. 5, a sheet with a movable contact provided with a spacer has a movable contact 13 formed by bulging the center in a dome shape with a conductive metal plate, and is bonded to a lower surface which covers the upper surface of the movable contact 13. A sheet 11 made of an insulating film to which an agent is applied, and a spacer sheet 12 made of an insulating film, which is attached to the lower surface of the sheet 11 and has a storage hole 12a for storing the movable contact 13. .

The movable contact 13 is housed in the housing hole 12a of the spacer sheet 12, and the upper surface of the dome is covered and fixed by an adhesive 14 applied to the lower surface of the sheet 11. The spacer sheet 12 has a connecting groove 12b connecting the storage holes 12a.
When the movable contact 13 is pressed by providing the connection groove 12b, air in the dome of the dome-shaped movable contact 13 flows through the connection groove 12b to another storage hole 12a. To prevent the operation feeling from becoming worse.

The sheet 11 and the spacer sheet 12 have openings 11a and 12c used as holes for illumination from LEDs mounted on the circuit board and holes for escape of components. It is provided at a plurality of locations.

The sheet switch shown in FIG. 6 is composed of the above-mentioned sheet with movable contacts, and a circuit board 15 provided with a central fixed contact 15b and an outer fixed contact 15a on the upper surface. The adhesive 16 on the lower surface of the spacer sheet 12 such that the lower end of the outer peripheral end 13b of the movable contact 13 abuts on the outer fixed contact 15a and the top 13a faces the central fixed contact 15b.
Is attached on the circuit board 15.

The sheet with a movable contact shown in FIG. 7 does not include a spacer sheet, and has a movable contact 13 formed by bulging the center in a dome shape with a conductive metal plate, and an upper surface of the movable contact 13. And a sheet 17 made of an insulating film having an adhesive applied to the lower surface.

In this case, an opening 17a (a round hole in the figure) formed of a wide through hole is provided at a portion of the sheet 17 which intersects with the outer peripheral end 13b of the movable contact 13. The opening 17a When the movable contact 13 is pressed, the air in the dome of the dome-shaped movable contact 13 escapes to the outside through the opening 17a to prevent the operation feeling from being deteriorated. are doing

The sheet switch shown in FIG. 8 comprises the above-mentioned sheet with movable contacts and a circuit board 15 provided with a center fixed contact 15b and an outer fixed contact 15a on the upper surface. The circuit board is fixed by the adhesive 18 on the lower surface of the sheet 17 so that the lower end of the outer peripheral end 13b of the movable contact 13 is in contact with the outer fixed contact 15a and the top 13a is opposed to the central fixed contact 15b. 15 is attached.

In the above configuration, when the operating portion of a rubber or resin push button (not shown) disposed above the sheet switch is pressed, the movable portion pressed by the pressing portion on the lower surface of the operating portion via the sheets 11 and 17 is provided. The contact 13 performs an inversion operation, and the lower surface of the top portion 13a contacts the central fixed contact 15b, so that the central fixed contact 15b and the outer fixed contact 15a of the circuit board 15 are electrically connected. When the pressing force on the push button is removed, the elastic contact force of the movable contact 13 returns to the top 1 of the movable contact 13.
3a is separated from the central fixed contact 15b and the connection is turned off.

[0011]

However, in the above-described conventional structure of the sheet with movable contacts and the sheet switch, the structure of the sheet with movable contacts with the spacer sheet requires the above-mentioned spacer sheet 12 and thus requires a smaller number of parts. However, there is a problem that the cost cannot be reduced.

In the structure of a sheet with movable contacts using a single sheet, the sheet 17 is attached to the circuit board 15 depending on the variation in the amount of the adhesive 18 applied and the state of attachment of the movable contacts 13. At this time, floating (indicated by X in FIG. 8) occurs particularly on the movable contact side arranged at the outermost periphery, and there is a possibility that dust may enter.

Further, since the sheet 17 is adhered along the bulging portion so as to cover the upper surface side of the dome-shaped movable contact 13, when the movable contact 13 is inverted, the outer peripheral end is warped. Therefore, there is a problem that the reversing operation becomes unstable by hitting the sheet 17.

Therefore, the present invention solves the above-mentioned problems, reduces the number of parts, and makes it possible to reduce costs. Even when a movable contact of a sheet with movable contacts and a sheet switch is pressed, the outer peripheral end of the movable contact is pressed. It is an object of the present invention to provide a structure of a sheet with a movable contact and a sheet switch, in which the operation feeling is improved by preventing a portion from being hit by a sheet, dust is prevented from entering, and high contact reliability is obtained.

[0015]

According to the present invention, as a first means for solving the above-mentioned problems, a sheet made of an insulating film and a dome-shaped bulged portion whose upper surface is covered and attached to the sheet are provided. The seat has a storage portion protruding to the upper surface side, and a bulging portion of the movable contact is attached to an inner surface of the storage portion with an adhesive.

[0016] As a second means, the storage section includes:
The cross section is formed in a substantially trapezoidal shape such that the inner bottom surface is flat and the width becomes narrower in the protruding direction, and the inner bottom edge of the storage portion having a substantially trapezoidal cross section is the movable contact. And an operation space portion with an outer peripheral end portion of the first embodiment.

As a third means, the seat is provided with a plurality of the accommodating portions, and a connection groove for air circulation is formed between the adjacent accommodating portions.

As a fourth means, the sheet is:
It is characterized by having an adhesive surface coated with an adhesive on the lower surface.

According to a fifth aspect of the present invention, there is provided a sheet with movable contacts according to any one of the first to fourth means, and a circuit board provided with fixed contacts. The sheet with the movable contacts is attached to the circuit board by an adhesive on a lower surface of the sheet in a state where the sheet is provided so as to face the fixed contacts.

[0020]

1 to 4 show an embodiment of the present invention. FIG. 1 is a cross-sectional view showing a sheet with movable contacts of the present invention, FIG. 2 is a cross-sectional view showing a sheet switch, FIG. 3 is a plan view showing a state in which a connection groove for air circulation is formed between sheet storage sections. 4 is a sectional view taken along line 4-4 in FIG.

In FIG. 1, a sheet 1 is formed in a film shape from an insulating material made of a synthetic resin such as PET (polyethylene terephthalate). Also, this sheet 1
An adhesive 2 is applied to one surface of the lower surface of the substrate to form a bonding surface to be fixed to a movable contact 3 to be described later or to be attached to a circuit board 4. Further, the sheet 1 is formed into an embossed shape by a mold or the like so as to protrude toward the upper surface side, and is formed with a storage portion 1a for storing therein a movable contact 3 described later. The storage portion 1a is formed such that the inner bottom surface is processed into a flat shape and the cross-sectional shape becomes substantially trapezoidal so that the width becomes narrower in the protruding direction on the upper surface side. ing.

In this case, when a movable contact 3 to be described later is accommodated in the accommodating portion 1a and the top 3a of the bulging portion of the movable contact 3 is adhered to the adhesive 2, the sectional shape of the accommodating portion 1a is substantially trapezoidal. The corner 1b formed on the inner bottom edge constitutes an operation space with the outer peripheral end 3b of the movable contact 3 described later.

The movable contact 3 is made of a springy metal material such as stainless steel or phosphor bronze, and is formed by bulging into a dome shape having a top 3a. The top 3a is turned to the opposite side by an external pressing operation. It is designed to be inverted. The movable contact 3 is disposed on an outer fixed contact 5a of a circuit board 4 to be described later. When the movable contact 3 is reversed by a pressing operation, the lower surface of the top 3a contacts and separates from the center fixed contact 5b to switch the contact. It has become.

In order to assemble the sheet with movable contacts, the movable contacts 3 are stored in the storage portion 1a of the sheet 1, and the upper surface of the dome of the movable contacts 3 is attached to the adhesive on the inner bottom surface of the storage portion 1a. 2 and adhered to the adhesive surface. In this case, the corner 1b formed at the inner bottom edge of the storage section 1a having a substantially trapezoidal cross section, and the outer end 3 of the movable contact 3
The movable contact 3 is fixed to the sheet 1 in this state.

FIG. 2 shows the structure of a sheet switch using a sheet with movable contacts according to the present invention, and is a sectional view of one key portion of the sheet switch. Note that the same components described in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

In the figure, a circuit board 4 is formed from an insulating laminated board such as a phenol resin. The outer fixed contacts 5a are printed on the circuit board 4 by printing carbon or the like or etching a copper foil or the like.
The circuit pattern of the center fixed contact 5b is provided.

To assemble the above sheet switch,
The movable contact-equipped sheet is positioned on the circuit board 4, a lower end of an outer peripheral end 3b of the movable contact 3 is in contact with the outer fixed contact 5a, and a top 3a faces the central fixed contact 5b. As described above, the assembling is completed by attaching the sheet 1 onto the circuit board 4 with the adhesive surface of the adhesive 2 applied to the lower surface of the sheet 1.

Next, the operation of the above-mentioned sheet switch will be described. When an operation portion of a rubber or resin push button (not shown) disposed above the sheet switch is pressed, the sheet 1 is pressed.
The movable contact 3 pressed via the 1 ’performs a reversing operation,
When the top 3a abuts on the central fixed contact 5b, the central fixed contact 5b of the circuit board 4 and the outer fixed contact 5a are electrically connected. At this time, the bulged portion of the dome-shaped movable contact 3 is inverted, and the top 3a
The outer peripheral end 3b is slightly curved upward as the outer peripheral end 3b is in contact with the central fixed contact 5b, but there is an operation space between the storage portion 1a of the seat 1 and the outer peripheral end 3b. Is formed, the reversing operation of the movable contact 3 is smoothly performed. When the pressing force on the push button is removed, the top 3a of the movable contact 3 is separated from the center fixed contact 5b by the elastic return force of the movable contact 3, and the connection is turned off.

In the above-described structure of the seat with movable contacts and the seat switch of the present invention, the seat 1 includes
The movable contact 3 is formed in an embossed shape by a mold or the like so as to protrude to the upper surface side, and a storage portion 1a for storing the movable contact 3 therein is formed.
Since it is housed and sealed, dust can be prevented from entering from the outside. Further, since the storage portion 1a is formed integrally with the sheet 1, the number of spacer sheets and the like can be reduced, and cost reduction can be achieved.

The storage portion 1a is formed so that its inner bottom surface is processed into a flat shape and its cross-sectional shape becomes substantially trapezoidal so that it becomes narrower in the protruding direction on the upper surface side. When the movable contact 3 is housed in the housing portion 1a and the top 3a of the bulging portion of the movable contact 3 is attached to the adhesive 2, it is formed on the inner bottom edge of the housing portion 1a having a substantially trapezoidal cross section. Since the formed corner portion 1b constitutes an operation space with the outer peripheral end 3b of the movable contact 3, the bulged portion of the dome-shaped movable contact 3 is inverted, and the top portion is formed. 3a
The outer peripheral end 3b is slightly curved upward as the outer peripheral end 3b is in contact with the central fixed contact 5b, but there is an operation space between the storage portion 1a of the seat 1 and the outer peripheral end 3b. Since the corner portion 1b is formed, the reversing operation of the movable contact 3 is performed smoothly, and a good operation feeling is obtained.

FIG. 3 is a plan view showing a state where a plurality of the movable contacts 3 are arranged on the sheet with movable contacts according to the present invention.
FIG. 4 is a sectional view taken along line 4-4 in FIG. Note that the same components described in FIGS. 1 and 2 are denoted by the same reference numerals and description thereof is omitted.

In the figure, a sheet 6 is formed in a single film from an insulating material made of a synthetic resin such as PET (polyethylene terephthalate). An adhesive 2 is applied on one surface of the lower surface of the sheet 6 to form an adhesive surface for fixing a plurality of the movable contacts 3 and affixing the sheet 6 on the circuit board 4. Have been. The seat 6 has a plurality of storage portions 6a for the movable contacts 3 fixed to the seat 6.
If the adhesive 2 is applied to the entire lower surface of the sheet 6 and the storage portion 6a is embossed with a mold or the like, the adhesive is easily applied to the inner bottom surface of the storage portion 6a. Agent 2 can be formed.

Further, a connecting groove 6c for air circulation is formed in the housing portion 6a between the adjacent housing portions 6a, 6a, and by forming the connecting groove 6c, the movable contact 3 is formed. When pressed, the air inside the dome of the dome-shaped movable contact 3 escapes to the other storage hole 6a through the connection groove 6c to prevent the operation feeling from being deteriorated. . In addition, since it is not necessary to provide an opening or the like for distributing air in the sheet 6, it is possible to prevent dust from entering from outside.

[0034]

As described above, the structure of the sheet with movable contacts according to the present invention comprises a sheet made of an insulating film and a movable contact having a dome-shaped bulging portion whose upper surface is covered and attached to the sheet. The seat has a storage portion protruding to the upper surface side, and the swelling portion of the movable contact is adhered to the inner surface of the storage portion with an adhesive, so that the movable contact is stored and sealed in the storage portion. Therefore, intrusion of dust from the outside can be prevented. In addition, since the storage section is formed integrally with the sheet, the number of spacer sheets and the like can be reduced, and cost reduction can be achieved.

The section has a substantially trapezoidal cross section so that the inner bottom surface is flat and narrows in the protruding direction. Since the bottom edge constitutes an operation space with the outer peripheral end of the movable contact, the bulge of the dome-shaped movable contact is inverted and the top comes into contact with the central fixed contact. Therefore, the outer peripheral edge is slightly curved upward, but since the corner portion, which is an operation space, is formed between the sheet storage portion and the outer peripheral edge, the movable contact can be smoothly inverted. And a good operation feeling is obtained.

The seat is provided with a plurality of storage portions, and a connection groove for air circulation is formed between adjacent storage portions, so that when the movable contact is pressed, a dome-shaped movable portion is formed. Since the air in the dome of the contact escapes to the other storage hole through the connection groove, deterioration of the operation feeling can be prevented. Further, since there is no need to provide an opening or the like for air distribution in the sheet, it is possible to prevent dust from entering from the outside.

Further, since the sheet has an adhesive surface coated with an adhesive on the lower surface, the adhesive can be easily formed on the inner bottom surface of the storage section.

Further, a seat with a movable contact having a storage portion protruding to the upper surface side, and a swelling portion of the movable contact attached to the inner surface of the storage portion with an adhesive, and a circuit board provided with fixed contacts are provided. Since the sheet with the movable contact is attached to the circuit board by the adhesive on the lower surface of the sheet in a state where the movable contact is arranged to face the fixed contact,
Even during the reversal operation of the movable contact, the movable contact is stored in the storage section and sealed, so that it is possible to prevent dust from entering from outside and causing a contact failure, and the reversal operation of the movable contact is smoothly performed, which is favorable. Operation feeling is obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a sheet with a movable contact according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a sheet switch using a sheet with movable contacts according to the present invention.

FIG. 3 is a plan view showing a state in which a connection groove for air circulation is formed between storage portions of a sheet with movable contacts according to the present invention.

FIG. 4 is a sectional view of the present invention taken along line 4-4 in FIG. 3;

FIG. 5 is an exploded perspective view showing a conventional sheet with a movable contact with a spacer.

FIG. 6 is a cross-sectional view showing a conventional sheet switch using a sheet with movable contacts with spacers.

FIG. 7 is a plan view showing a conventional sheet with movable contacts having a single-sheet structure.

FIG. 8 is a cross-sectional view showing a conventional sheet switch using a sheet with a movable contact having a single sheet structure.

[Explanation of symbols]

 1, 6 sheet 1a, 6a storage section 1b, 6b corner 2 adhesive 3 movable contact 3a top 3b outer peripheral end 4 circuit board 5a outer fixed contact 5b central fixed contact 6c connecting groove

Claims (5)

[Claims] 1. A sheet made of an insulating film, and a movable contact having a dome-shaped bulging portion which is attached to the sheet so as to cover the upper surface thereof, wherein the sheet has a storage portion protruding toward the upper surface. A sheet with a movable contact, wherein a swelling portion of the movable contact is adhered to an inner surface of the storage portion with an adhesive. 2. The storage section has a substantially trapezoidal cross section such that the inner bottom surface is flat and narrows in a protruding direction, and the storage section has a substantially trapezoidal cross section. The seat with a movable contact according to claim 1, wherein an inner bottom edge of the seat forms an operation space with an outer peripheral end of the movable contact. 3. The seat according to claim 1, wherein a plurality of the storage portions are provided on the sheet, and a connection groove for air circulation is formed between the adjacent storage portions. Seat with movable contacts. 4. The sheet with movable contacts according to claim 1, wherein the sheet has an adhesive surface with an adhesive applied to a lower surface. 5. A sheet having a movable contact according to claim 1, and a circuit board provided with a fixed contact, wherein the movable contact is disposed so as to face the fixed contact. Wherein the sheet with movable contacts is adhered to the circuit board with an adhesive on a lower surface of the sheet in a state where the sheet is in a folded state.