KR200374558Y1 - Key Panel Lamp Switch With Metal Dome - Google Patents

Abstract

A lower panel including a lower panel portion and a lower circuit portion stacked on the upper surface of the lower panel portion by a printing process and having a plurality of fixed contacts formed thereon; An intermediate panel stacked on the lower panel and having holes formed at positions corresponding to the plurality of fixed contacts; An upper panel laminated on the intermediate panel, and having an upper circuit portion laminated on the lower surface of the upper panel portion and the upper panel portion by a printing process and having movable contacts formed at positions corresponding to the plurality of fixed contacts; A metal dome disposed on each of the positions corresponding to the plurality of movable contacts on the upper panel; An EL sheet laminated on the metal dome and emitting light when power is applied; A projection pad provided on the EL sheet and provided with a projection for pressing the plurality of metal domes; It is installed on the projection pad, characterized in that consisting of a key panel provided with a key for each position corresponding to the plurality of projections.

Description

Key Panel Lamp Switch With Metal Dome}

The present invention relates to a key panel lamp switch, and more particularly, to a key panel lamp switch to which an EL lamp is applied and a metal dome with improved switching function is applied.

In general, a key panel lamp switch is a switch device for signal generation used in a communication device such as a mobile phone, and when used in a dark place, a lamp provided to illuminate a key printed with numerals or letters.

1 is a cross-sectional view of a conventional general key panel lamp switch, which includes a key panel 110, a protruding pad 120, a top tape 130, a base tape 140, a metal dome 150, an LED 160, and It consists of a printed circuit board 170.

Here, the LED 160 is typically mounted by soldering to a pattern formed on the surface of the printed circuit board 170 by applying Surface Mount Technology (SMT). In addition, since the printed circuit board 170 must be designed in a minimum size so that the printed circuit board 170 can be disposed in a limited space, the printed circuit board 170 is manufactured in a multi-layer (eg, 8 or 10 layers) structure. In addition, the fixed contact terminal 172 of the printed circuit board 170 is thinly coated (plated) with a material such as gold to prevent corrosion of the terminal surface and improve contact resistance.

Looking at the operation principle of the switch, when the user presses the predetermined key 112 of the key panel 110, the predetermined protrusion 122 of the projection pad 120 is pressed by the projection 122, the predetermined metal dome 150 The deformed contact with the predetermined fixed contact terminal 172 of the printed circuit board 170 is switched to generate a predetermined key signal.

However, such a key panel lamp switch may cause the following problems. That is, due to the characteristics of the LED 160, the light emitted is not uniformly irradiated to the entire key panel 110, and when a predetermined deviation occurs when fabricating the assembly state by assembling each component, the key When the predetermined key 112 of the panel 110 is pressed, there is a problem in that the normal switching does not occur.

In addition, since the fixed contact terminal 172 of the plated printed circuit board 170 may be deformed due to a foreign material such as a fingerprint, a great care is required during a work process. In addition, since two layers are used in the multilayered printed circuit board 170 to process the fixed contact terminal 172 divided into + and-, the remaining layers design the component layout and the pattern of the main circuit. Difficulties will follow.

In order to solve the above problems, the present invention provides a key panel lamp switch to which a metal dome is applied which not only irradiates light uniformly but also improves the switching function and work process to improve the reliability of the product. have.

In order to achieve the above object, the key panel lamp switch to which the metal dome according to the present invention is applied is provided on a lower panel and a lower panel including a lower circuit part in which a plurality of fixed contacts are formed by stacking a print process on an upper surface of the lower panel part. and; An intermediate panel stacked on the lower panel and having holes formed at positions corresponding to the plurality of fixed contacts; An upper panel laminated on the intermediate panel, and having an upper circuit portion laminated on the lower surface of the upper panel portion and the upper panel portion by a printing process and having movable contacts formed at positions corresponding to the plurality of fixed contacts; A metal dome disposed on each of the positions corresponding to the plurality of movable contacts on the upper panel; An electroluminescent (EL) sheet laminated on the metal dome and emitting light when power is applied; A projection pad provided on the EL sheet and provided with a projection for pressing the plurality of metal domes; It is installed on the projection pad, characterized in that consisting of a key panel provided with a key for each position corresponding to the plurality of projections.

In addition, a key panel lamp switch to which a metal dome of another form according to the present invention is applied may include: a lower panel including a lower panel portion and a lower circuit portion stacked on the upper surface of the lower panel portion by a printing process and having a plurality of fixed contacts; An intermediate panel stacked on the lower panel and having holes formed at positions corresponding to the plurality of fixed contacts; An upper panel laminated on the intermediate panel, and having an upper circuit portion laminated on the lower surface of the upper panel portion and the upper panel portion by a printing process and having movable contacts formed at positions corresponding to the plurality of fixed contacts; A metal dome disposed on each of the positions corresponding to the plurality of movable contacts on the upper panel; A protrusion pad installed on the metal dome and provided with a protrusion for pressing the plurality of metal domes; An EL sheet laminated on the protruding pad and emitting light upon application of power; And a key panel provided on the EL sheet and provided with a key for each position corresponding to the plurality of projections.

In the key panel lamp switch to which the metal dome is applied, it is more preferable to block electromagnetic interference by stacking an Electro-Magnetic Interference (EMI) layer on the upper surface of the EL sheet by a printing process. Further, the key panel lamp switch is more preferably provided with a reinforcing plate having a flat function and an insulation function under the lower panel.

1 is a cross-sectional view of a conventional general key panel lamp switch,

2 is a cross-sectional view of a first embodiment of a key panel lamp switch to which a metal dome is applied according to the present invention;

3 is an exploded perspective view of the upper panel, the middle panel, and the lower panel of FIG. 2, FIG.

4 is a cross-sectional view of a second embodiment of a key panel lamp switch to which a metal dome according to the present invention is applied.

* Explanation of symbols for main parts of the drawings

210,410: key panel 212,412: key

220,450: projection pad 222,452: projection

230,250,420,440,460,470: Bonded 240,430: EL Sheet

260,480 Metal Dome 270,490 Upper Panel

272,492: upper panel portion 274,494: upper circuit portion

274-1,494-1: Movable contact 280,500: Intermediate panel

282,502: hole 290,510: lower panel

292,512: Lower circuit part 292-1,512-1: Fixed contact

294,514: lower panel

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a cross-sectional view of a first embodiment of a key panel lamp switch to which a metal dome is applied according to the present invention, and FIG. 3 is an exploded perspective view of the upper panel, the middle panel, and the lower panel of FIG. 2. As shown in FIG. 2, the key panel lamp switch to which the metal dome is applied includes the key panel 210, the protrusion pad 220, the joints 230 and 250, the EL sheet 240, the metal dome 260, and the upper panel ( 270, an intermediate panel 280, and a lower panel 290.

Referring to FIG. 2, the key panel 210 is generally made of a material such as plastic, and includes a plurality of keys 212 in which predetermined numbers or letters are formed by printing or cutting.

The protrusion pad 220 is made of a material such as silicone rubber or synthetic resin, and includes a protrusion 222 corresponding to the plurality of keys 212. The protrusion pad 220 may be attached to the key panel 210 by a double-sided adhesive tape, a bond, and ultrasonic welding.

The EL sheet 240 has a structure in which a light emitting electrode layer, a dielectric layer, a light emitting layer, and a transparent electrode film layer are stacked, and when power is applied, the light emitting layer emits light to illuminate the key panel 210 located above. Since the laminated structure of the EL sheet 240 is a well known technique, a detailed description thereof will be omitted. The protruding pad 220 and the EL sheet 240 may be adhesively fixed by the bonding material 230.

Further, it is more preferable that a predetermined electromagnetic interference shielding layer (not shown) be laminated on the upper surface of the EL sheet 240 by further printing. Then, it is possible to effectively block electrostatic discharge (ESD) or radiation, which may affect the EL sheet 240.

The metal dome 260 has a property of causing deformation by a predetermined force applied from the outside so as to feel a predetermined click and returning to the original state when the force is removed. 222 is provided for each position corresponding to.

Therefore, when the user clicks on a predetermined key 212 of the key panel 210, the corresponding protrusion 222 of the corresponding protrusion pad 220 is pressed and the corresponding metal dome via the EL sheet 240. FIG. Force is applied to 260 to cause deformation, and when the user releases a finger from a predetermined key 212 of the key panel 210, the force applied to the metal dome 260 is removed to return to the original state. do. Here, the EL sheet 240 and the metal dome 260 can be bonded with a predetermined bonding material 250 such as a double-sided adhesive tape or the like.

2 and 3, the upper panel 270 includes an upper panel portion 272 and an upper circuit portion 274 having movable contacts 274-1 formed at positions corresponding to the plurality of protrusions 222. do. Here, the upper circuit portion 274 is bonded to the lower surface of the upper panel portion 272 by a printing process.

The intermediate panel 280 is positioned below the upper panel 270, and a predetermined hole 282 is formed at each position corresponding to the plurality of movable contacts 274-1.

The lower panel 290 includes a lower panel portion 294 and a lower circuit portion 292 having fixed contacts 292-1 formed at positions corresponding to the plurality of movable contacts 274-1. Here, the lower circuit portion 292 is bonded to the upper surface of the lower panel portion 294 by a printing process. The fixed contact 292-1 of the lower circuit portion 292 has opposite polarities as compared to the movable contact 274-1 of the upper circuit portion 274.

As described above, the key panel lamp switch to which the metal dome is applied includes the upper panel 270 formed by stacking the upper circuit part 274 on the upper panel part 272 by a printing process, and the lower circuit part on the lower panel part 294. 292 may be manufactured in a package form, such as a lower panel 290 formed by laminating a print process, to minimize deviations that may occur during an assembly process, and to improve a work process.

Here, the upper panel 270, the middle panel 280, and the lower panel 290 may be simply stacked without using a separate joint, or a joint such as a double-sided adhesive tape may be bonded to each other. . In addition, a predetermined connection terminal (not shown) is formed in the upper circuit portion 274 and the lower circuit portion 292, and may be connected to a main printed circuit board (not shown) by using a flexible printed circuit (FPC) cable.

In this case, the connection terminals and the cable terminals formed in the circuit units 274 and 292 may be connected in various forms. For example, after the cable is inserted into a predetermined groove (not shown) formed in the intermediate panel 280, a hot press process is performed to connect the connection terminal and the cable terminal formed in the circuit portions 274 and 292 to each other, or to connect a double-sided adhesive tape or the like. It can be connected and fixed by the bonding of the adhesive.

In addition, a predetermined connection terminal (not shown) formed in the intermediate panel 280 is connected to the connection terminals of the circuit portions 274 and 292, and other predetermined connection terminals (not shown) formed in a portion protruding to the outside of the intermediate panel 280. Cable terminal may be connected by a predetermined connector.

On the other hand, the lower panel 290 under the predetermined shape to maintain the shape of the lower panel 290 and to prevent electricity from flowing between the lower panel 290 and the main printed circuit board located below the lower panel 290. It is more preferable to provide a reinforcement plate (not shown) further. Here, the reinforcing plate may be attached to the lower panel 290 by a bonding material such as double-sided adhesive tape or hot press treatment.

Now, referring to the operation principle of the key panel lamp switch to which the metal dome is applied, the predetermined protrusion 222 of the protrusion pad 220 when the user presses a predetermined key 212 of the key panel 210 with a finger. Is pressed, the metal dome 260 is pressed through the EL sheet 240, and as a result, the upper panel 270 is pressed to apply a force to a predetermined movable contact 274-1 of the upper circuit portion 274.

Then, a predetermined movable contact 274-1 of the upper circuit portion 274 to which a force is applied passes through a predetermined hole 282 formed in the intermediate panel 280 and corresponding corresponding fixed contact of the lower circuit portion 292. (292-1). That is, the predetermined movable contact 274-1 of the upper circuit portion 274 and the predetermined fixed contact 292-1 of the lower circuit portion 292 are brought into contact with each other so as to be turned on to be turned on.

When the user releases his / her finger from the predetermined key 212 of the key panel 210, the metal dome 260 is returned to its original state by an elastic action, and the predetermined movable contact 274-of the upper circuit unit 274. 1) and the contact between the predetermined fixed contact 292-1 of the lower circuit portion 292 fall. That is, the predetermined movable contact 274-1 of the upper circuit portion 274 and the predetermined fixed contact 292-1 of the lower circuit portion 292 are shorted to switch from the on state to the off state.

FIG. 4 is a cross-sectional view of a second embodiment of a key panel lamp switch to which a metal dome is applied according to the present invention. The key panel lamp switch to which the metal dome is shown in FIG. 420, 440, 460, 470, EL sheet 430, protrusion pad 450, metal dome 480, upper panel 490, middle panel 500, and lower panel 510.

In the key panel lamp switch to which the metal dome shown in FIG. 4 is applied, when compared with the key panel lamp switch to which the metal dome is shown in FIG. 2, the EL sheet 430 is located directly under the key panel 410, and The protrusion pad 450 is located directly below the EL sheet 430. Here, the key panel 410 and the EL sheet 430, the EL sheet 430, and the projection pad 450 may be adhesively fixed to a predetermined bonding material 420 and 440, respectively. In addition, an electromagnetic interference shielding layer for effectively blocking electrostatic discharge or radiation may be further stacked on the upper surface of the EL sheet 430.

Meanwhile, the upper panel 490, the middle panel 500, and the lower panel 510 are stacked in the same order to perform a switching function. Since the basic operating principle of the key panel lamp switch to which the metal dome is shown in FIG. 4 is the same as the operating principle of the key panel lamp switch to which the metal dome is shown in FIG. 2, a detailed description thereof will be omitted.

According to the present invention, by using EL lamp as the light emitting source, it is possible to miniaturize the product and the light emitted can be uniformly irradiated to the key panel. In addition, by using a metal dome, a feeling of click can be improved. In addition, the use of the panel in the form of a package can minimize the deviation that can occur during the assembly process and improve the work process to reduce the defective rate to improve the reliability of the product.

In addition, by stacking the electromagnetic interference shielding layer, it is possible to minimize the effects of electrostatic discharge or radiation, thereby improving the reliability of the product. In addition, by treating the contact terminals in the circuit printed layer, the pattern design of the main circuit is relatively easy, and the cost can be reduced by the reduced layer of the printed circuit board.

Claims (4)

A lower panel including a lower panel portion and a lower circuit portion stacked on the upper surface of the lower panel portion by a printing process and having a plurality of fixed contacts formed thereon; An intermediate panel stacked on the lower panel and having holes formed at positions corresponding to the plurality of fixed contacts; An upper panel laminated on the intermediate panel, and having an upper circuit portion laminated on the lower surface of the upper panel portion and the upper panel portion by a printing process and having movable contacts formed at positions corresponding to the plurality of fixed contacts; A metal dome disposed on each of the positions corresponding to the plurality of movable contacts on the upper panel; An EL sheet laminated on the metal dome and emitting light when power is applied; A projection pad provided on the EL sheet and provided with a projection for pressing the plurality of metal domes; The key panel lamp switch of claim 1, wherein a metal dome is formed on the protrusion pads and includes a key panel provided with a key for each position corresponding to the plurality of protrusions. A lower panel including a lower panel portion and a lower circuit portion stacked on the upper surface of the lower panel portion by a printing process and having a plurality of fixed contacts formed thereon; An intermediate panel stacked on the lower panel and having holes formed at positions corresponding to the plurality of fixed contacts; An upper panel laminated on the intermediate panel, and having an upper circuit portion laminated on the lower surface of the upper panel portion and the upper panel portion by a printing process and having movable contacts formed at positions corresponding to the plurality of fixed contacts; A metal dome disposed on each of the positions corresponding to the plurality of movable contacts on the upper panel; A protrusion pad installed on the metal dome and provided with a protrusion for pressing the plurality of metal domes; An EL sheet laminated on the protruding pad and emitting light upon application of power; A key panel lamp switch having a metal dome provided on the EL sheet and comprising a key panel provided with a key for each position corresponding to the plurality of projections. The method according to claim 1 or 2, A key panel lamp switch to which a metal dome is applied, wherein an electromagnetic interference shielding layer is laminated on the upper surface of the EL sheet by a printing process. The method according to claim 1 or 2, Key panel lamp switch with a metal dome, characterized in that the reinforcement plate is further provided with a flat function and an insulation function beneath the lower panel.