JP2002319328A - Push button switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the structure of a push button switch capable of easily preventing the bulging out of an adhesive when being pressed even if an accumulation part of the adhesive by a resist layer is not formed when an insulator is fixed. SOLUTION: This push button switch is equipped with a plurality of connection terminals 1f, 1g formed in the side end part of an insulating substrate 1 and connected to a soldering pattern 1k on the lower surface; a pair of fixed contacts 1a, 1b connected to the connection terminals 1f, 1g and formed on the upper surface of the insulating substrate 1; a moving contact 3 arranged on the fixed contacts 1a, 1b; an insulator 2 attached to the upper surface of the insulating substrate 1 and having a housing hole 2a for housing the moving contact 3; and a spacer 5 attached to the lower surface of the insulating substrate and having cutout parts 5a to which the soldering pattern 1k is exposed. Projection parts 2b positioning in a projected region of the notch part 5a of the spacer 5 and projecting to the inside of the housing hole 2a are installed in the insulator 2, and the moving contact 3 is positioned and regulated inside the housing hole 2a with the projection parts 2b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a push-button switch in which a dome-shaped movable contact is turned over when pressed to contact and separate the contact, and more particularly to a structure of a thin push-button switch based on an insulating substrate. .

[0002]

2. Description of the Related Art As a conventional structure of a thin push button switch based on an insulating substrate, a switch substrate is formed based on an insulating substrate made of glass epoxy resin or the like. On the upper surface of the switch substrate, a pair of fixed contacts made of a conductive pattern plated with nickel or gold on a copper foil is provided, and one of the fixed contacts is formed by a through-hole or a pattern on the surface. It is connected to the conductive pattern on the back side of the substrate.

On the switch board, a sheet-like insulator made of a polyimide resin or the like having a storage hole at the center and a thermosetting adhesive applied to both sides thereof is fixed. In the storage hole of this insulator,
The one fixed contact and the central contact are opposed to each other, the other fixed contact is connected to the peripheral edge, and a movable contact formed by bulging the center into a dome shape with a conductive metal plate is housed therein.

A film-like cover sheet also made of polyimide resin or the like is mounted on the upper side of the movable contact and the insulator, and is fixed with an adhesive applied to the insulator. I have.

At the four ends of the switch board, connection terminals to be connected to a circuit pattern of a circuit board such as an electronic device are formed in through-holes or copper foil in the form of electrodes by a method such as nickel base or gold plating. And are electrically connected to the pair of fixed contacts.

A sheet-like spacer made of a polyimide resin or the like to which a thermosetting adhesive is applied is fixed to the lower surface of the switch board so as to cover the conductive pattern and the through hole on the back side. Notches are provided at four ends of the spacer to expose the connection terminals.

When an insulator, a cover sheet, a spacer, and the like are laminated and fixed to the switch board, a thermosetting adhesive is used to apply heat and cure under pressure from above and below to fix the switch board. Was like that. Note that when pressure is applied, the adhesive may protrude to the movable contact side and adhere to the contact portion. Therefore, a slight space is provided by applying a resist layer to the switch substrate, and the adhesive at the time of pressurization is provided. An escape of the agent was formed.

The above-mentioned conventional push button switch is mounted on a circuit board of an electronic device or the like, the connection terminal is connected to a circuit pattern, and the center of the dome-shaped movable contact is pressed by an external operation member. And the switch is switched in contact with one of the fixed contacts.

[0009]

However, in the structure of the conventional push button switch described above, it is difficult to control the position accuracy and the thickness on the switch substrate surface corresponding to a predetermined range at the time of forming the resist layer. There is a problem that the cost is increased due to the complexity, and the switch substrate is warped by providing the resist layer.

[0010] Therefore, the present invention solves the above-mentioned problems, and has a structure of a thin push-button switch based on an insulating substrate, and does not need to form an escape portion of an adhesive by a resist layer when the insulator is fixed. It is an object of the present invention to provide a structure of a push button switch that can easily prevent the adhesive from protruding during pressurization.

[0011]

In order to solve the above-mentioned problems, the present invention provides, as a first means, an insulating substrate having a soldering pattern on a lower surface and the soldering pattern formed on a side end of the insulating substrate. A plurality of connection terminals for connection with
A pair of fixed contacts, which are connected to the plurality of connection terminals and are formed facing the upper surface of the insulating substrate, are disposed on the fixed contacts, and are in the form of a dome that conducts between the fixed contacts by being inverted. A movable contact, an insulator attached to the upper surface of the insulating substrate and having a storage hole for accommodating the movable contact, and a spacer attached to the lower surface of the insulating substrate and having a cutout for exposing the soldering pattern The insulator is provided with a projection that is located within the projection area of the cutout portion of the spacer and protrudes toward the inside of the storage hole, and the movable contact is stored in the projection by the projection. The position is regulated in the hole.

As a second means, an insulating substrate having a soldering pattern on a lower surface, a plurality of connection terminals formed at side ends of the insulating substrate and connected to the soldering pattern, and a plurality of connection terminals A pair of fixed contacts formed facing the upper surface of the insulating substrate, and a dome-shaped movable contact disposed on the fixed contacts and conducting between the fixed contacts by inversion, An insulator attached to the upper surface of the insulating substrate and having an accommodation hole for accommodating the movable contact, and a spacer attached to the lower surface of the insulating substrate and having a cutout portion exposing the soldering pattern, The movable contact has a projection that is located within the projection area of the notch of the spacer and protrudes outward from the outer periphery of the movable contact. The characterized in that the position regulating in the housing bore.

As a third means, the insulating substrate comprises a square insulating substrate having the soldering pattern formed at four corners and the connection terminals connected thereto, and the protrusion is provided on the insulating substrate. The movable contact is positioned corresponding to the four corners, and the position of the movable contact is regulated in the storage hole by the protrusion.

[0014]

1 to 7 show an embodiment of a push button switch according to the present invention. 1 is an exploded perspective view of the push button switch, FIG. 2 is a plan view thereof, FIG. 3 is a bottom view thereof,
4 is a sectional view of the same, FIG. 5 is a sectional view of a main part of the push button switch, FIG. 6 is a plan view showing a modification, and FIG. 7 is a perspective view showing an assembling process.

In FIG. 1, a switch substrate 1 made of an insulating substrate is formed in a square shape from an insulating laminate such as a glass epoxy resin. On the front side of the switch substrate 1, a pair of fixed contacts made of a copper foil pattern, that is, a center fixed contact 1a provided at the center, and a peripheral fixed contact 1b provided annularly around the center fixed contact 1a.
Are formed.

On the back side of the switch substrate 1,
A first conductive pattern 1c also formed of a copper foil pattern is formed, and the first conductive pattern 1c is electrically connected to the center fixed contact 1a through a through hole 1d penetrating the switch substrate 1. I have. A second conductive pattern 1e, also made of a copper foil pattern, is formed on the front side of the switch substrate 1.
Are electrically connected to the peripheral fixed contact 1b.

The through hole 1d is provided on the center fixed contact 1a and the peripheral fixed contact 1b.
The central fixed contact 1a is formed at a position facing a central contact formed in a dome-shaped bulging portion of the movable contact 3, which will be described later.
And the central contact of the movable contact 3 are in line contact, not surface contact, so that reliable contact can be obtained even when foreign matter enters the contact portion, and the contact portion is stable even if the position of the contact portion is slightly deviated from the center. Contact is obtained.

Further, at the four ends of the switch substrate 1,
Connection terminals 1f and 1g connected to a circuit pattern of a circuit board such as an electronic device (not shown) are formed in through-holes or copper foil in the form of electrodes by a method such as nickel base or gold plating. The connection terminals 1f and 1g are electrically connected to each other in a pair. The first connection terminal 1f is connected to the center fixed contact 1a, and the second connection terminal 1g is connected to the peripheral fixed contact 1a. A contact 1b, the first conductive pattern 1c and the second conductive pattern 1 respectively;
e are electrically connected.

The first connection terminal 1f and the center fixed contact 1a are connected on the back side of the switch substrate 1 by the first conductive pattern 1c.
On the front surface side of the switch substrate 1, the first connection terminal 1f is separated from the peripheral fixed contact 1b by a long continuous groove 1j (gap), and becomes electrically disconnected. I have.

The second conductive pattern 1e is
Except for the plurality of narrow grooves 1h, the narrow groove 1h is formed on the entire surface of the switch substrate surface in a range surrounded by the continuous groove 1j and the peripheral fixed contact 1b. It is provided in a band shape substantially at the center along the conductive pattern 1e. Further, the narrow groove portion 1h is provided in the second
Is formed between the end face of the storage hole 2a of the insulator 2 and the end face of the outer shape, which will be described later, which is stuck on the conductive pattern 1e, and the distance from the end face of the storage hole 2a of the insulator 2, It is formed in a band shape at a position where the distance from the end face of the outer shape is substantially equal in the entire circumference of the storage hole 2a.

In this case, the second conductive pattern 1e connecting the peripheral fixed contact 1b and the second connection terminal 1g is provided with the narrow groove portion 1h, whereby the second conductive pattern 1e is provided.
When the insulator 2 to be described later is adhered to the conductive pattern 1e, when the adhesive is heated and cured in a state where the adhesive is pressed from above and below, bubbles generated at the time of pressurization may escape to the narrow groove 1h. Since the second conductive pattern 1e can be formed in a wide range, the bonding margin of the insulator 2 can be secured widely, and there is no need to increase the pressing force to expel air bubbles to both ends of the insulator 2. It is possible to prevent the appearance quality from being deteriorated due to protrusion or generated bubbles.

Further, solder patterns 1k connected to the first and second connection terminals 1f and 1g are formed at four corners on the rear surface side of the switch substrate 1. The soldering pattern 1k is connected to the first and second connection terminals 1f and 1g.
When the solder is provided, the solder goes around to the back side of the switch substrate 1 at the time of soldering, so that the connection can be surely made.

The insulator 2 is formed of an insulating material such as a polyimide resin into a square sheet. In the center of the insulator 2, a substantially circular opening-shaped storage hole 2 a is provided.
Are provided, and a movable contact 3 described later is stored in the storage hole 2a. The storage hole 2a is formed with four protrusions 2b projecting toward the inside of the storage hole 2a on diagonal lines connecting four corners.
The contact b restricts the position of the movable contact 3 in the housing hole 2a by contacting the outer peripheral portion of the movable contact 3 described later. A thermosetting adhesive is applied to the front and back sides of the insulator 2 to form an adhesive layer 6.

The movable contact 3 is made of a conductive metal plate,
The center is formed in a disk shape bulging in a dome shape,
The center contact point is turned upside down and is opposed to the central fixed contact 1a so as to be able to come into contact with and separate from the central fixed contact 1a, and the peripheral portion is always connected to the peripheral fixed contact 1b. It is in a state of being housed and held in.

The cover sheet 4 is also formed of a rectangular film made of an insulating material such as a polyimide resin. The cover sheet 4 covers the movable contact 3 and the insulator 2 so as to cover the upper surface of the insulator 2. 2 is fixed by the adhesive layer 6 made of an adhesive.

The spacer 5 is made of an insulating material such as polyimide resin, which is the same material as the insulator 2, and is formed in a square film shape. The spacer 5 is formed on the back surface of the switch substrate 1. The first conductive pattern 1c is fixed to the back surface of the switch substrate 1 by an adhesive layer 7 made of an adhesive so as to cover the upper surface of the conductive pattern 1c.

At four corners of the spacer 5, rectangular notches 5a are formed at positions corresponding to the soldering patterns 1k.
The notch 5a is provided so that the soldering pattern 1k is exposed on the lower surface of the switch substrate 1. The notch 5a and the protrusion 2b formed in the housing hole 2a of the insulator 2 are arranged at positions corresponding to the upper and lower sides when they are laminated, and the protrusion 2b is It is arranged so as to be located within the projection area of the notch 5a.

As described above, the projection 2b for positioning the movable contact 3 in the storage hole 2a of the insulator 2 is arranged so as to be located within the projection area of the notch 5a of the spacer 5. Therefore, when the adhesive layer 6 is stacked on the switch substrate 1, the lower surface side of the protrusion 2 b contacting the movable contact 3 becomes hollow due to the cutout 5 a of the spacer 5, so that the adhesive layer 6 is heated. Since the pressure applied to the tip of the projection 2b is reduced when the adhesive is fixed by pressing, the adhesive can be prevented from protruding to the movable contact 3 side.

Further, since the projections 2b for regulating the position of the movable contact 3 in the housing hole 2a of the insulator 2 are arranged at the four corners of the switch substrate 1, the outer shape can be reduced, and the size of the switch can be reduced. It becomes possible.

Further, the spacer 5 is provided with the soldering pattern 1k and the electrode-like first and second connection terminals 1f and 1g formed at the ends of the switch substrate 1 at the portions other than the soldering pattern 1k. It is attached so as to be thicker than the thickness of the attachment pattern 1k. By making the spacer 5 thicker than the thickness of the soldering pattern 1k on the back surface side of the switch substrate 1, the soldering pattern 1 is removed from the first and second connection terminals 1f and 1g during soldering.
It is possible to prevent the switch substrate 1 from floating due to the solder flowing into the lower surface of k.

Next, a method of assembling the push button switch in the above embodiment will be described. First, the switch board 1
The spacer 5 is laminated via the adhesive layer 7 on the first conductive pattern 1c and the through hole 1d on the back surface side of the substrate and temporarily bonded to close the through hole of the through hole 1d.

Next, the insulator 2 is laminated via an adhesive layer 6 on the front side of the switch substrate 1, that is, on the side where the central fixed contact 1a and the peripheral fixed contact 1b are formed.

Next, the storage hole 2 of the insulator 2
The movable contact 3 is housed in such a manner that the central contact of the dome-shaped bulging portion is opposed to the central fixed contact 1a, and the peripheral edge is in contact with the peripheral fixed contact 1b. Are positioned at predetermined positions on the fixed contacts 1a and 1b.

In this state, the cover sheet 4 is put on the movable contact 3 and the insulator 2 so as to cover the upper surface of the insulator 2 and temporarily bonded.

Next, the insulator 2, the cover sheet 4, and the spacer 5 are fixed on the switch substrate 1 by heating and pressing the adhesive layer 6 of the insulator 2 and the adhesive layer 7 of the spacer 5. The assembly is completed.

As described above, by blocking the through hole 1d with the spacer 5, it is possible to prevent dust and the like from entering from the through hole 1d after the switch is assembled.

FIG. 7 shows an assembling process in which a plurality of push-button switches can be assembled at the same time when assembling the push-button switches in the above embodiment. A plurality of central fixed contacts 1a and peripheral fixed contacts 1b are formed, and the insulator 2, movable contact 3, cover sheet 4, and spacer 5 laminated on the switch board 1 also have a plurality of central fixed contacts 1a and It is formed so as to correspond to the peripheral fixed contact 1b.

Then, after assembling the push-button switches by the above-described assembling method, the individual push-button switches are formed by individually cutting the respective push-button switches.

When the adhesive layer 6 of the insulator 2 is fixed on the switch substrate 1 by heating and pressing,
Since the spacer 5 is on the back surface of the switch substrate 1 corresponding to the insulator 2, the adhesive of the adhesive layer 6 protrudes toward the movable contact 3 when pressurized and adheres to the contact portion. There was a possibility.

For this reason, in the present embodiment, a projection 2b for regulating the position of the movable contact 3 is provided in the housing hole 2a of the insulator 2, and this projection 2b is formed by a notch of the spacer 5. 5a, the projections 2b contact with the movable contact 3 when stacked on the switch substrate 1.
The lower surface side of the spacer 5 becomes a cavity due to the cutout portion 5a of the spacer 5, so that when the adhesive layer 6 is fixed by heating and pressing, the pressure applied to the tip of the protrusion 2b is reduced. The protrusion can be prevented from protruding to the movable contact 3 side.

FIG. 6 shows another embodiment of the push button switch according to the present invention. 1 to 5 are denoted by the same reference numerals, and description thereof will be omitted.

The difference from the structure of the above embodiment shown in FIGS. 1 to 5 is that the protrusion 2b for positioning the movable contact 3 in the housing hole 2a of the insulator 2 is different from that of the insulator 2 shown in FIG.
Instead, it is formed on the outer periphery of the movable contact.

That is, in the present embodiment, the four outer projecting portions are provided on the outer peripheral portion of the movable contact 3 at positions corresponding to the notches 5 a formed at the four corners of the spacer 5. A projection 3a is formed. This projection 3
a is positioned in the projection area of the notch 5a of the spacer 5 and incorporated, and the protrusion 3a is brought into contact with the inner peripheral portion of the storage hole 2a of the insulator 2 so that the movable member 5 The position of the contact 3 is regulated in the accommodation hole 2a. It should be noted that even when the movable contact 3 is incorporated, even if there is some rotation in the housing hole 2a of the insulator 2, the area facing the end face of the adhesive layer 6 can be reduced by the projection 3a.

In this case, the movable contact 3 made of a metal plate
Since the projection 3a can be formed by press working, the projection can be easily formed. Also in this case, when the insulator 2 is laminated on the switch substrate 1, the lower surface of the protrusion 3a provided on the outer peripheral portion of the movable contact 3, which is in contact with the inner peripheral portion of the housing hole 2a. ,
Since the cavity is formed by the notch 5a of the spacer 5, when the adhesive layer 6 is fixed by heating and pressing, it is applied to the inner peripheral portion of the housing hole 2a of the insulator 2 corresponding to the tip of the protrusion 3a. Since the pressure is reduced, the adhesive can be prevented from protruding to the movable contact 3 side.

[0045]

As described above, the push button switch according to the present invention comprises: an insulating substrate having a soldering pattern on a lower surface;
A plurality of connection terminals formed at side ends of the insulating substrate and connected to the soldering pattern; a pair of fixed contacts connected to the plurality of connection terminals and formed facing the upper surface of the insulating substrate; A dome-shaped movable contact that is disposed on the contact and conducts between the fixed contacts by inversion, an insulator that is attached to the upper surface of the insulating substrate and has a storage hole for storing the movable contact, and an A spacer having a cutout portion that is attached and exposes the soldering pattern, and the insulator has a projection portion that is located within the projection region of the cutout portion of the spacer and protrudes toward the inside of the storage hole. Since the movable contact is positioned in the storage hole by the protrusion, the lower surface side of the protrusion contacting the movable contact when stacked on the switch board is formed in the notch of the spacer. Ri since the cavity, heating the adhesive layer,
At the time of pressing and fixing, the pressure applied to the tip of the projection is reduced, so that the adhesive can be prevented from protruding to the movable contact side.

Also, an insulating substrate having a soldering pattern on the lower surface, a plurality of connection terminals formed on side edges of the insulating substrate and connected to the soldering pattern, and a plurality of connection terminals connected to the plurality of connection terminals, A pair of fixed contacts formed facing the upper surface, a dome-shaped movable contact disposed on the fixed contacts and conducting between the fixed contacts by inversion, and a movable contact attached to the upper surface of the insulating substrate; An insulator having a storage hole for storing the contact, and a spacer having a cutout portion attached to the lower surface of the insulating substrate and exposing the soldering pattern, wherein the movable contact is provided within a projection area of the cutout portion of the spacer. And a protrusion protruding outward from the outer periphery of the movable contact is formed, and the position of the movable contact within the storage hole is regulated by this protrusion. In this case, since the lower surface side of the protrusion that comes into contact with the movable contact becomes a cavity due to the cutout portion of the spacer, the pressure applied to the tip of the protrusion is reduced when the adhesive layer is fixed by heating and pressing. Further, the adhesive can be prevented from protruding to the movable contact side. In addition, since the protrusion can be formed on the movable contact made of a metal plate by pressing, the formation of the protrusion is facilitated.

The insulating substrate comprises a square insulating substrate having the soldering pattern and connection terminals connected to the soldering pattern at four corners. The protrusions are arranged corresponding to the four corners of the insulating substrate. Since the position of the movable contact in the storage hole is regulated by the portion, the protrusions are arranged using the four corners of the square, so that the outer shape of the insulating substrate can be reduced, and the size of the switch can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a push button switch according to an embodiment of the present invention.

FIG. 2 is a plan view showing the same push button switch of the present invention.

FIG. 3 is a bottom view showing the same push button switch of the present invention.

FIG. 4 is a sectional view showing the same push button switch of the present invention.

FIG. 5 is a sectional view of a main part of the push button switch of the present invention.

FIG. 6 is a plan view showing a push button switch according to another embodiment of the present invention.

FIG. 7 is a perspective view showing an assembling process of the push button switch of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switch board (insulating board) 1a Central fixed contact 1b Peripheral fixed contact 1c First conductive pattern 1d Through hole 1e Second conductive pattern 1f First connection terminal 1g Second connection terminal 1h Long groove 1j Continuous groove (gap) Part) 1k soldering pattern 2 insulator 2a receiving hole 2b protrusion 3 movable contact 3a protrusion 4 cover sheet 5 spacer 5a notch 6,7 adhesive layer

Claims (3)

[Claims] 1. An insulating substrate having a soldering pattern on a lower surface, a plurality of connection terminals formed on a side end of the insulating substrate and connected to the soldering pattern; A pair of fixed contacts formed facing the upper surface of the substrate, a dome-shaped movable contact disposed on the fixed contacts and conducting between the fixed contacts by inversion, and affixed to the upper surface of the insulating substrate; An insulator having an accommodation hole for accommodating the movable contact, and a spacer affixed to the lower surface of the insulating substrate and having a cutout portion exposing the soldering pattern, wherein the insulator includes the spacer A projection is formed within the projection area of the notch, and protrudes toward the inside of the storage hole. The position of the movable contact is regulated in the storage hole by the projection. A push button switch, characterized in that: 2. An insulating substrate having a soldering pattern on a lower surface, a plurality of connection terminals formed on a side end of the insulating substrate and connected to the soldering pattern, the plurality of connection terminals being connected to the plurality of connection terminals, A pair of fixed contacts formed facing the upper surface of the substrate, a dome-shaped movable contact disposed on the fixed contacts and conducting between the fixed contacts by inversion, and affixed to the upper surface of the insulating substrate; An insulator having an accommodation hole for accommodating the movable contact, and a spacer affixed to the lower surface of the insulating substrate and having a cutout for exposing the soldering pattern, wherein the movable contact has A protrusion is formed within the projection area of the notch of the spacer and protrudes outward from the outer periphery of the movable contact, and the movable contact is positioned in the storage hole by the protrusion. Push button switch characterized by control. 3. The insulating substrate comprises a rectangular insulating substrate having the soldering pattern at four corners and the connection terminals connected to the soldering pattern, and the protrusions are arranged corresponding to the four corners of the insulating substrate. The position of the movable contact is regulated in the storage hole by the protrusion.
Or the pushbutton switch according to 2.