JP2012248483A - Illumination key switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illumination key switch for entirely uniform light emission without using a light guide sheet with a prismatic structure or reflective dot printing.SOLUTION: An illumination key switch 10 includes: a key switch 12 having two contacts provided on a substrate 11 and spaced apart from each other; a light source 13 provided on one side of the key switch 12 on the substrate 11 for emitting light in a direction perpendicular to the substrate 11; and an illumination switch plate 14 that is disposed above the key switch 12 and the light source 13 and is made of a light-transmitting member for pressing the key switch 12 and in which an illumination surface section 14a comprising a surface facing the key switch 12 and an opposite surface is illuminated by light from the light source 13. The illumination switch plate 14 includes a reflective section 14c for reflecting light entered from an incoming light surface section 14b comprising a surface facing the light source toward the upper side of the key switch 12. A fine uneven structure for irregular reflection of light reflected by the reflective section 14c to the illumination surface section 14a is formed on at least part of a peripheral surface excluding the illumination surface section 14a and the incoming light surface section 14b.

Description

  The present invention relates to an illumination key switch used for an operation panel of an electric device.

  Patent Document 1 discloses an illumination key switch having an illumination function used for an electric device. The illumination key switch described in the reference example of FIG. 4 of Patent Document 1 includes a substrate provided with a central contact and a fixed contact portion serving as an outer peripheral contact disposed around the central contact on the surface, and an outer periphery of the substrate. A switch dome having an outer peripheral edge abutting on the contact and having a movable contact portion at the top of the head facing the central contact, and a spacer mounted on the substrate to irradiate the light toward the upper side of the switch dome. A light emitting element composed of an LED; a light guide sheet disposed above the switch dome to guide light of the light emitting element above the top of the switch dome; and an upper surface disposed above the light guide sheet And a push mat portion, and a plunger provided on the lower surface is inserted into a plunger hole formed in the light guide sheet and includes a key mat that contacts the top of the switch dome. There. A light guide sheet used for such an illumination key switch is provided with a prism structure or reflective dot printing in order to illuminate the light emitting surface on the upper surface. In this illumination key switch, when the push button portion of the key mat is pressed, the movable contact portion of the switch dome contacts the center contact and is electrically connected, and the illumination key switch is turned on. At this time, the light emitting element is energized to emit light, and the light of the light emitting element is propagated inward from the incident surface on the side surface of the light guide sheet, and the light emitting surface composed of the upper surface of the light guide sheet is reflected by a prism structure or reflective dot printing. Illuminated by the light.

JP 2010-061955 A

  In the illumination key switch described in the reference example of FIG. 4 of Patent Document 1, the light of the light emitting element is guided to the illumination surface on the upper surface of the push button portion of the key mat by the light guide sheet. Since the light sheet is thin, the amount of incident light is limited, and the opposite side of the light incident portion of the light guide sheet may not be sufficiently illuminated. If the light emitting elements are provided on both sides of the light guide sheet, the entire light guide sheet can be sufficiently illuminated, but there may be a case where a space for mounting the light emitting elements cannot be secured, and even if there is a space for mounting There was a problem of high costs. Moreover, since the light guide sheet has a prism structure for reflecting light and reflection dot printing, the cost of an illumination key switch using the light guide sheet is increased, and the light guide sheet serving as an input unit The thickness of the side surface of the plate could not be easily changed. In addition, this illumination key switch has a problem that the cost including assembly work increases because of the large number of parts. The present invention aims to solve these problems.

  In order to solve the above problems, the present invention provides a key switch provided on a substrate, a light source that is provided on one side of the key switch on the substrate and that emits light in a direction perpendicular to the substrate, and a key switch. And an illuminating switch plate made of a translucent member for illuminating with light from the light source and pressing the key switch. The switch plate has a reflecting portion that reflects light input from the light incident surface portion formed by a surface facing the light source toward the upper side of the key switch, and is provided on at least a part of the peripheral surface excluding the illumination surface portion and the light incident surface portion. It is an object of the present invention to provide an illumination key switch characterized in that fine irregularities are formed to diffusely reflect light reflected by a reflection portion toward an illumination surface portion.

  In the illumination key switch configured as described above, the illumination switch plate includes a reflection portion that reflects light input from the light incident surface portion that is a surface facing the light source toward the upper side of the key switch, Since fine irregularities are formed on at least a part of the peripheral surface excluding the light incident surface portion to diffusely reflect the light reflected by the reflection portion toward the illumination surface portion side, the light emitted from the light source is reflected above the key switch by the reflection portion Reflected and reflected light is diffusely reflected on the side of the illuminated surface due to minute irregularities formed on the peripheral surface of the illuminated switch plate, and the illuminated surface portion of the illuminated switch plate is uniformly distributed as a whole by this irregularly reflected light. Comes illuminated. In addition, the illumination switch plate of this illumination key switch has both functions of a conventional key top that presses the key switch and a conventional light guide sheet that guides the light of the light source, so the number of parts is reduced. Cost can be reduced.

  In the illumination key switch configured as described above, the light incident from the light incident surface portion on the peripheral edge portion on the other side opposite to the one side where the light source of the illumination switch plate is provided is reflected by the reflection portion. In addition, since the second reflecting portion is further reflected to the illumination surface portion side, the light incident from the light incident surface portion is more efficient not only on the light incident surface portion side on one side but also on the other side where the light is reflected by the reflection portion. The illumination surface portion can be illuminated well.

  In the illumination key switch configured as described above, the illumination switch plate is made of a translucent resin member, and it is preferable that the unevenness is formed by embossing. In such a case, the unevenness is easily formed on the illumination switch plate. It becomes possible to process.

(A) It is a front view of the illumination key switch which is one Embodiment of this invention, (b) It is a longitudinal cross-sectional view. (A) It is a front view of an illumination switch board, (b) It is a rear view of an illumination switch board, (c) It is a side view of an illumination switch board, (d) It is a top view of an illumination switch board. (A) It is a front view of the modification of an illumination switch board, (b) It is a rear view of the modification of an illumination switch board, (c) It is a side view of the modification of an illumination switch board, (d) Illumination switch It is a top view of the modification of a board.

  Hereinafter, an embodiment of an illumination key switch of the present invention will be described with reference to the accompanying drawings. As shown in FIGS. 1 and 2, the illumination key switch 10 according to the present embodiment is used for an operation switch of an operation panel P of an electric device such as a steam convection oven, for example, and is provided on a substrate 11 and is mutually connected. A key switch 12 having two contact points separated from each other; a light source 13 provided on one side of the key switch on the substrate 11 for irradiating light in a direction perpendicular to the substrate 11; and the key switch 12 and the light source 13 An illuminating switch made of a translucent member that is disposed on the upper side in the vertical direction with respect to the substrate 11 and that is illuminated by the light from the light source 13 to illuminate the illuminating surface portion 14a composed of the opposite surface of the key switch 12. And a plate 14.

  A substrate 11 of an illumination key switch 10 is provided in the operation panel P, and a key switch 12 is provided on the substrate 11 on the front side of the steam convection oven. The key switch 12 includes two fixed contacts (not shown) fixed on the substrate 11 so as to be spaced apart from each other, a case portion 12a made of a magnet that accommodates these fixed contacts, and a top plate portion of the case portion 12a. The switch portion 12b is formed of a conductive metal member that connects two fixed contacts when pressed and protruded from the through hole formed in the upper and lower portions. In this key switch 12, when the switch portion 12b is pressed, the switch portion 12b moves to the inside against the magnetic force of the housing portion 12a, and the switch portion 12b simultaneously contacts two fixed contacts and 2 The two fixed contacts are conducted by the switch portion 12b.

  An LED 13 is provided as a light source on one side of the key switch 12 on the substrate 11. The LED 13 emits light in a direction perpendicular to the substrate 11 when the key switch 12 is turned on. is there.

  Illuminated switch plate 14 for pressing the switch portion 12b of the key switch 12 on the upper side of the key switch 12 and the LED 13 in the vertical direction with respect to the substrate 11 (in this embodiment, the substrate 11 is set up vertically so that the front side). Is provided. The illumination switch plate 14 is, for example, an acrylic plate having translucency, and is formed by injection molding. The illumination switch plate 14 has an illumination surface portion 14 a that is illuminated by the light of the LED 13 on the opposite surface of the key switch 12. In the illumination switch plate 14, the surface of the key switch 12 facing the LED 13 is a light incident surface portion 14 b that allows light to enter. On the surface opposite to the light incident surface portion 14b at the lower part of the illumination switch plate 14, the lower side is inclined toward the light incident surface portion 14b side (back side) so as to reflect the light of the LED 13 toward the switch portion 12b side of the key switch 12. A first reflecting portion (reflecting portion) 14c is formed. Further, the illumination switch plate 14 has a surface opposite to the illumination surface portion 14a of the illumination switch plate 14 as a peripheral portion on the upper side (the other side) opposite to the lower side (one side) in FIG. A second reflecting portion 14d that is inclined toward the illumination surface portion 14a is formed on the upper portion and the side portion that continues from there. The second reflecting portion 14d enters the light incident surface portion 14b and is reflected on the upper side of the key switch 12 by the first reflecting portion 14c to the other side away from the light incident surface portion 14b of the illumination surface portion 14a. Further, it is reflected.

  The illumination switch plate 14 is subjected to a textured process including minute irregularities on the portion excluding the illumination surface portion 14a, the light incident surface portion 14b and the first reflection portion 14c at the time of molding (shown by the dot pattern in FIG. 2B). The light reflected by the first reflecting portion 14c toward the switch portion 12b is irregularly reflected by minute irregularities formed on each surface by embossing and irradiated from the illumination surface portion 14a. Further, a surface sheet P1 covering the front surface of the operation panel P is bonded to the illumination surface plate 14a side of the illumination switch plate 14 of the illumination key switch 10, and the surface sheet P1 faces the illumination surface portion 14a of the illumination switch plate 14. The illumination surface P1a is transparent. When a mirror-like reflective tape R (indicated by a two-dot chain line in FIGS. 1A and 2A) is applied to the lower front portion of the illumination switch plate 14 except the illumination surface portion 14a and the first reflection portion 14c. The light of the LED 13 can be efficiently reflected to the switch part 12b side, and the illumination surface part 14a can be further brightened.

  In the illumination key switch 10 configured as described above, the illumination switch plate 14 reflects the light input from the light incident surface portion 14b formed by the surface facing the LED 13 toward the upper side of the switch portion 12b of the key switch 12. 1 uneven part 14c, and a fine unevenness that diffuses light reflected by the first reflecting part 14c toward the illuminating face part 14a on the peripheral surface excluding the illuminating face part 14a, the incident light face part 14b, and the first reflecting part 14c Was formed by embossing. The light emitted from the LED 13 is reflected toward the upper side of the switch part 12b of the key switch 12 by the first reflecting part 14c, and the reflected light is minute unevenness formed by embossing on the peripheral surface of the illumination switch plate 14 Therefore, the light is irregularly reflected on the illumination surface portion 14a side. Thereby, the illumination surface portion 14a of the illumination switch plate 14 is illuminated so as to be uniform as a whole by the light irregularly reflected by the fine irregularities formed on the peripheral surface of the illumination switch plate 14. The illumination switch plate 14 of the illumination key switch 10 has both functions of a conventional key top for pressing the key switch 12 and a conventional light guide sheet for guiding the light of the light source. The cost can be reduced by reducing the cost.

  Further, in the illumination key switch 10, as the peripheral portion on the other side opposite to the one side on which the LED 13 of the illumination switch plate 14 is provided, the upper portion of the illumination switch plate 14 opposite to the illumination surface portion 14 a and from here on. A second reflecting portion 14d that is inclined toward the illumination surface portion 14a is formed on the continuous side portion. The second reflecting portion 14d further reflects the light of the LED 13 incident on the light incident surface portion 14b and reflected on the upper side of the key switch 12 by the first reflecting portion 14c on the side away from the light incident surface portion 14b of the illumination surface portion 14a. It is something to be made. As a result, the illumination switch plate 14 is brightly illuminated on the opposite side away from the light incident surface portion 14b, and the illumination surface portion 14a is illuminated more uniformly.

  Further, in this illumination key switch 10, the illumination switch plate 14 is made of a light-transmitting resin member such as acrylic, and fine irregularities are formed at the time of injection molding by embossing. The unevenness can be easily processed. In addition, the illumination switch plate 14 is only partially subjected to a textured process for irregularly reflecting the light of the LED 13, and does not use a special material or a special process, so that the cost is high. Never become. Further, since the illumination switch plate 14 is formed by injection molding a translucent resin member, the shape and thickness of the illumination switch plate 14 can be easily changed. The LED 13 used as the light source of the illumination key switch 10 is a top view type that irradiates light in a direction perpendicular to the substrate 11 and is the same top view type as other LEDs used for the operation panel P. Compared with the case of using a side view type that irradiates light in parallel to a conventional substrate, the number of parts can be reduced and the cost can be reduced.

  In the illumination key switch 10 of this embodiment, white printing or white paint may be applied to the surface of the illumination switch plate 14 facing the key switch 12 (excluding the light incident surface portion 14b). When this is done, the light emitted from the LED 13 and reflected by the first reflecting portion 14c toward the upper side of the switch portion 12b of the key switch 12 is less likely to leak to the surface of the illumination switch plate 14 facing the key switch 12. The illumination surface portion 14a of the illumination switch plate 14 can be further brightened.

  Further, a white sheet may be affixed to the surface of the illumination switch plate 14 facing the key switch 12 (excluding the light incident surface portion 14b), and in this case, the switch portion 12b of the key switch 12 is placed above the switch portion 12b. The light reflected toward the surface of the illumination switch plate 14 is less likely to leak to the surface of the illumination switch plate 14 facing the key switch 12, and the illumination surface portion 14a of the illumination switch plate 14 can be further brightened. Further, when this sheet is attached to the surface of the illumination switch plate 14 facing the key switch 12 (excluding the light incident surface portion 14b), the switch portion 12b of the key switch 12 is prevented from appearing as a shadow on the illumination surface portion 14a. be able to. Further, when the sheet is affixed, it is possible to prevent the contact surface of the illumination switch plate 14 with the switch portion 12b from being finely scratched due to long-term use, and a shadow appears on the illumination surface portion 14a due to this scratch. Can be prevented.

  Further, when a sheet is affixed to the surface of the illumination switch plate 14 facing the key switch 12 (excluding the light incident surface portion 14b), the reflection efficiency toward the illumination surface portion 14a can be improved. As shown in the modification of the plate 14, the illumination surface portion 14a is sufficiently illuminated even when the second reflection portions 14d on both sides of the surface of the illumination switch plate 14 facing the key switch 12 are eliminated to make it easier to stick the sheet. Can do.

 DESCRIPTION OF SYMBOLS 10 ... Illumination key switch, 11 ... Board | substrate, 12 ... Key switch, 13 ... Light source (LED), 14 ... Illumination switch board, 14a ... Illumination surface part, 14b ... Light-incidence surface part, 14c ... Reflection part (1st reflection part), 14d ... 2nd reflection part.

Claims (3)

A key switch provided on the substrate;
A light source that is provided on one side of the key switch on the substrate and emits light in a direction perpendicular to the substrate;
Illumination made of a translucent member that is disposed above the key switch and the light source and illuminates with light from the light source and illuminates an illumination surface portion composed of the opposite surface of the key switch. With a switch plate,
The illumination switch plate has a reflection portion that reflects light input from an incident surface portion formed by a surface facing the light source toward an upper side of the key switch, and a peripheral surface excluding the illumination surface portion and the incident surface portion. An illumination key switch characterized in that fine irregularities are formed on at least a part of a surface to diffusely reflect the light reflected by the reflection portion toward the illumination surface portion. The illuminated switch according to claim 1.
The light incident from the light incident surface portion on the peripheral portion on the other side opposite to the one side on which the light source of the illumination switch plate is provided is further reflected to the illumination surface portion side after being reflected by the reflection portion. An illumination key switch having a second reflecting portion to be operated.
The illuminated key switch according to claim 1 or 2,
The illumination key switch is characterized in that the illumination switch plate is made of a translucent resin member, and the irregularities are formed by embossing.

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