JP2006310004A - Illuminated tactile switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact illuminated tactile switch capable of improving illumination efficiency of a switch part by irradiating a periphery of a center part of a plate spring with light emitted from a light emitting part at the shortest distance, and enabling to assemble and form the light emitting part and the plate spring compactly. <P>SOLUTION: The illuminated tactile switch 21 provided with the conductive plate spring 25 for covering an upper part of a contact point 24 and the light emitting part 26 arranged in a periphery of the plate spring 25 has a curved part 32 formed on a side surface of the plate spring 25, and is arranged so as to let the light emitting part 26 get deep into the curved part 32. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a small and thin illumination type tact switch having an illumination function by a light emitting element.

  As shown in FIG. 6, the conventional illuminated tact switch has a rectangular substrate 2 with a contact 4 serving as a fixed electrode formed in the center, and a substrate 2 that covers the upper side of the contact 4. The conductive plate spring 5 is disposed, and a light emitting portion 6 disposed at a corner portion of the substrate 2 is formed. The illuminated tact switch 1 is widely used in touch panels of various electronic devices including mobile phones that are becoming smaller and thinner.

In order to cope with such miniaturization and thinning, it is necessary to accommodate the plate spring 5 and the light emitting portion 6 in a compact substrate 2 in a compact manner. Moreover, in order to improve visibility and operability, improvement of illumination efficiency is also required. In the illuminated tact switch 1 as shown in FIG. 6, a switch portion 3 including a contact 4 and a circular plate spring 5 is formed at the center of the substrate 2, and the light emitting portion 6 is disposed at a corner portion of the substrate 2. By arranging and forming, the substrate 2 is effectively used and miniaturized. Further, with respect to the illumination efficiency for the switch unit 3, the light emitting unit 6 is provided at a plurality of corners of the substrate 2, and an improvement effect is achieved by increasing the number of light emitting elements 7 arranged in each light emitting unit 6. .
LS6 series, data sheet, [online], Citizen Electronics Co., Ltd., “Search January 5, 2005”, Internet URL <http: // www. ce. co.jp/products/index1.html>

  However, in the illuminated tact switch 1 as shown in FIG. 6, the light emitting unit 6 is provided close to the plate spring 5. However, since the plate spring 5 is circular, If the size of 2 is to be minimized, the position where the light emitting unit 6 is arranged is limited to the corner of the substrate 2. Further, the shorter the distance from the light emitting portion 6 to the center portion of the switch portion 3, the greater the illumination effect, but it cannot be shortened because it depends on the size of the plate spring 5 to be arranged. For this reason, there is a problem that a significant improvement in illumination efficiency cannot be obtained with the switch unit 3 as the center.

  Therefore, an object of the present invention is to increase the illumination efficiency of the switch unit by irradiating the light emitted from the light emitting unit toward the vicinity of the central part of the plate spring at the shortest distance, and to increase the light emitting unit and the plate spring. It is an object of the present invention to provide a compact illuminated tact switch that can be compactly assembled and formed.

  In order to solve the above-described problems, an illuminated tact switch according to the present invention includes an electrically conductive plate spring covering an upper portion of a contact, and an illuminated tact switch including a light emitting unit disposed in the vicinity of the plate spring. In the switch, a curved portion is formed on at least one side surface of the plate spring, and the light emitting portion is arranged so as to enter deeply into the curved portion.

  According to the illuminated tact switch of the present invention, a curved portion is provided on one side surface of the plate spring, and the light emitting portion is arranged so as to penetrate deeply into the curved portion, whereby the vicinity of the center portion of the plate spring. It is possible to set a short distance for irradiation. This makes it possible to illuminate the entire plate spring, which is the center of the pressing operation of the switch, with high brightness and efficiency.

  In addition, since the light-emitting part can be incorporated on the board with the light-emitting part deeply entering the curved part of the plate spring, the size of the board can be minimized, and high-density mounting and mounting in a narrow space are easy. It becomes.

  Embodiments of an illuminated tact switch according to the present invention will be described below in detail with reference to the accompanying drawings.

  As shown in FIGS. 1 to 3, the illuminated tact switch 21 of the present invention includes a rectangular substrate 22, a switch portion 23 formed at the center of the substrate 22, and one side surface of the switch portion 23. And the light emitting unit 26 disposed in the.

  The substrate 22 is made of a resin material such as glass epoxy, and a switch circuit (not shown) constituting the switch unit 23 on the upper surface, and a contact 24 serving as a fixed electrode on the switch circuit and electrodes and wirings in the light emitting unit 26. A pattern is formed. An external connection electrode 30 for mounting on a mother board is provided on the outer peripheral surface of the substrate 22. In the substrate 22 shown in FIGS. 1 and 2, the external connection electrode 30 is formed by a through hole, but may be formed by a lead frame.

  The switch portion 23 is composed of the contact 24 and a substantially rectangular conductive plate spring 25 that covers the contact 24. The plate spring 25 is a movable electrode that comes into contact with the contact 24 and is made of a thin and elastic metal material such as stainless steel (SUS) or brass. This plate-like spring 25 has a central portion that is in contact with the contact 24, and is shaped to slightly bulge upward so as not to contact the contact 24 in a normal state, with four corners formed by a molding material. Positioned on the substrate 22. Then, the contact with the contact 24 is achieved by touching or pressing the central portion of the plate spring 25.

  The plate-like spring 25 has side surfaces facing in four directions, and a curved portion 32 cut out in an arc shape toward the inside is formed on each side surface. The curved portion 32 is formed by cutting into a circular arc shape with a predetermined width on the inner side with the four corners as base points, and has a certain curvature toward the center of the plate spring 25 positioned directly above the contact 24. Is formed. In the present embodiment, in order to make the shape of the plate spring 25 symmetrical, the curved portions 32 are provided on all the side surfaces in the four directions. However, for the purpose of arranging the light emitting portions 26 described later in proximity, It is only necessary to provide the curved portion 32 only on the side facing the light emitting portion 26.

  The light emitting unit 26 includes a light emitting element 27 and a translucent sealing body 28 that covers the light emitting element 27. The light emitting element 27 is composed of one or more light emitting diodes (LEDs), and is mounted in a space near the curved portion 32 on the substrate 22. The light emitting element 27 is selected from white or single color light emission such as red, blue, green and the like according to the illumination application, and a plurality of the light emitting elements 27 can be arranged according to the light emission intensity. Further, when emitting color light, like the illuminated tact switch 41 shown in FIG. 4, three light emitting elements 27a, 27b, and 27c of red, blue, and green are arranged, and the respective light emitting elements 27a, 27b, and 27c are arranged. Various light emitting effects can be obtained by adjusting the current value to be supplied.

  As shown in FIGS. 3 and 5, the sealing body 28 is formed to have a predetermined thickness in order to accommodate the light emitting element 27. In addition, the outer peripheral edge 34 is formed so as to extend in an arc shape along the curved portion 32, and the thickness thereof is a flat ellipse that gradually decreases from the center of the sealing portion 28 toward the outer peripheral edge 34. It has a shape. For this reason, the directivity of the light emitted from the light emitting element 27 can be directed to the center of the plate spring 25 from both the planar direction and the thickness direction. As a result, the vicinity of the contact 24 in contact with the plate spring 25 can be illuminated most brightly.

  Further, by arranging the light emitting element 27 closer to the outer peripheral edge 34 that is closest to the curved portion 32, the amount of light applied to the central portion of the plate spring 25 can be further increased, and the sealing body 28 is provided. The curved portion 32 can be compactly accommodated.

  Further, by filling the sealing body 28 with a translucent resin material in which a fluorescent agent, a diffusing agent, or the like is mixed, the emission intensity in the light emitting portion 26 can be increased. With such a configuration, an efficient illumination effect with reduced power consumption can be obtained.

  Further, a frame portion 35 surrounding the periphery of the plate spring 25 is provided on the outer peripheral portion of the substrate 22 excluding the light emitting portion 26. The frame portion 35 is provided to position the plate spring 25 on the substrate 22 and seal the side surface. The frame portion 35 is formed at substantially the same height as the central portion of the plate spring 25, and a translucent waterproof sheet 29 is attached through the frame portion 35.

  The illuminated tact switch 21 having the above configuration is directly surface-mounted on a mother board (not shown) and soldered by reflow processing.

  The light emitting unit 26 emits light when the plate spring 25 which is a movable electrode comes into contact with a contact 24 (fixed electrode) on the substrate 22 by a pressing operation, and turns off when the pressing operation is released. . According to the illuminated tact switch 21 of the present embodiment, when a pressing operation is performed with a finger or the like, irradiation from the light emitting element 27 is received from a position close to the center portion of the plate spring 25, so the luminance of the pressed portion is high. Thus, the operability is improved. Further, since the sealing body 28 constituting the light emitting portion 26 is formed to have an outer peripheral edge 34 projecting in an arc shape so as to follow the curved portion 32 of the plate spring 25, the light emitting element 27 The emitted light can be efficiently irradiated to the entire switch unit 23 without leakage.

  In addition, the light emitting portion 26 can be disposed so as to be accommodated in the space of the curved portion 32 of the plate spring 25, and a wiring pattern can be formed in the curved portion 32. Therefore, the size of the substrate 22 is reduced. It is only necessary to provide a space for configuring the switch unit 26. For this reason, compared with the tact switch provided with the conventional illumination function, size reduction of about 70 to 80% was attained.

  The illuminated tact switch 21 of the above embodiment is suitable for an independent single tact switch because the switch unit 23 and the light emitting unit 26 have a one-to-one correspondence. If a plurality of set configurations of the switch unit 23 and the light emitting unit 26 are arranged on the collective board, the number of components and wiring between boards are reduced, and it is efficiently incorporated into a mobile phone or a terminal device having a unified key arrangement. It becomes possible.

It is a perspective view of the illumination type tact switch which concerns on this invention. It is a perspective view which shows the internal structure of the illumination type tact switch of the said FIG. It is a top view of the illumination type tact switch of the said FIG. It is a top view of the illumination type tact switch provided with the light emission part by a several light emitting element. It is sectional drawing of the illumination type tact switch of the said FIG. It is a perspective view of the conventional illumination type tact switch.

Explanation of symbols

DESCRIPTION OF SYMBOLS 21 Illuminated tact switch 22 Board | substrate 23 Switch part 24 Contact 25 Plate-like spring 26 Light emission part 27 Light emitting element 28 Sealing body 29 Waterproof sheet 30 External connection electrode 32 Bending part 34 Outer periphery

Claims (4)

In an illuminated tact switch comprising a conductive plate spring that covers the upper side of the contact and a light emitting unit disposed in the vicinity of the plate spring,
An illuminated tact switch, wherein a curved portion is formed on at least one side surface of the plate spring, and the light emitting portion is disposed deeply into the curved portion. The light emitting unit includes one or more light emitting elements and a light-transmitting sealing body that seals the light emitting elements, and an outer peripheral edge of the sealing body is formed along the curved portion. The illuminated tact switch according to claim 1. The illuminated tact switch according to claim 2, wherein the sealing body is formed in a cross-sectional shape such that the thickness thereof gradually decreases toward the outer peripheral edge. A circuit board, a contact disposed on the circuit board, a curved part formed on at least one side surface, a plate spring covering the upper side of the contact, and a circuit board disposed so as to penetrate deeply into the curved part An illuminated tact switch characterized by comprising a light emitting portion.

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