JP4495694B2 - Light guide and power window switch - Google Patents

Description

  The present invention relates to a light guide for guiding light emitted from a light source to a plurality of display units, and a power window switch using the light guide.

  As shown in FIG. 8, a light guide that can illuminate a plurality of display units with light emitted from a single light source has been conventionally known (for example, see Patent Document 1). As shown in the figure, the light guide 100 is formed by forming a single transparent resin in a substantially comb shape, and a light source 101 is disposed in a concave incident portion 100a provided in a part thereof. The tip of each of the light emitting portions 100b branched into three faces a plurality of display portions provided on a display panel (not shown). With such a configuration, the light from the light source 101 is guided to each emitting unit 100b through a path as indicated by a broken line in the figure, and therefore the corresponding display unit is illuminated by the light emitted from each emitting unit 100b. Can do.

Further, in a power window switch that automatically opens and closes the windows of the driver's seat, the passenger seat, and the rear seat of the vehicle, conventionally, four seesaw knobs arranged in two vertical and horizontal rows corresponding to each window are provided in the housing. Light emitted from a plurality of light sources (for example, four LEDs) mounted on a printed circuit board, which is supported in a swingable manner and has a drive mechanism, a switch mechanism, or the like corresponding to each seesaw knob inside the housing. By irradiating the back surface of each seesaw knob through the rubber sheet that is a component of the switch mechanism, the display part of each seesaw knob is illuminated in the dark place such as at night or in a tunnel (for example, , See Patent Document 2).
JP-A-5-164923 Japanese Patent Laid-Open No. 2002-334631

  However, in the conventional light guide 100 shown in FIG. 8, the light from the light source 101 reaches the light emitting portion 100b located in the center as it is, whereas the light emitting portions 100b located on both the left and right sides are light sources. 101 light arrives after being reflected by the inclined surface, and thus the amount of light emitted from each light emitting portion 100b varies greatly depending on the distance to the light source 101, and a plurality of light beams illuminated by the light emitted from each light emitting portion 100b. There is a problem that the luminance of the display portion becomes non-uniform.

  On the other hand, in the above-described conventional power window switch, the display portions of the four seesaw knobs are individually illuminated by the light of a plurality of light sources mounted on the printed circuit board. If they are not set to be the same, the four seesaw knobs cannot be illuminated with uniform brightness, and it is difficult to efficiently guide the light from each light source to the back surface of the seesaw knob. Further, since drive mechanisms for driving the rubber seats of the switch mechanism are respectively provided below the seesaw knobs, the back surfaces of the total four seesaw knobs arranged in two rows and four rows are as shown in FIG. It is difficult to illuminate the display portions of the four seesaw knobs with uniform brightness using such a light guide and one light source. .

  The present invention has been made in view of the situation of the prior art as described above, and a first object thereof is to guide light capable of illuminating a plurality of display units with uniform luminance by light emitted from one light source. The second object of the present invention is to provide a power window switch that can illuminate the display section of four seesaw knobs with uniform brightness using a pair of light sources and a light guide. There is to do.

In order to achieve the first object described above, a light guide of the present invention is a light guide for guiding light emitted from a light source to a plurality of display units, and a light incident unit facing the light source; A first light guide portion that bifurcates from the light incident portion with a predetermined radius of curvature, and a pair of second light guide portions that extend from the first light guide portion in the opposite direction along the same plane; A plurality of third light guides each branching from the second light guides with a predetermined radius of curvature and extending along the plane direction, and the tips of the third light guides are orthogonal to the plane. A fourth light guide portion extending in a direction, and guides light emitted from the light source to the display portion through the first to fourth light guide portions. the branch end configured to form a bridge connecting the proximal end side to each other of the two second light guide unit.

According to the light guide configured as described above, a large amount of light is reflected on the outer peripheral side of the curvature facing the light source in the first light guide that branches into a bifurcated shape with a predetermined curvature radius from the light incident portion. On the other hand, since the light reflected on the inner peripheral side is smaller than that on the outer peripheral side, the pair of second light guides extending in the opposite direction along the same plane from the first light guide part The difference in luminance between the front and back surfaces is large in a region close to one light guide portion, and the luminance on both front and back surfaces is gradually made uniform as the distance from the first light guide portion increases. Therefore, in the plurality of third light guide parts branched from the second light guide part with a predetermined radius of curvature, the surface is formed along the plane direction even if it is branched at a position close to the first light guide part. configure backside as one third light guide section, as they may have a fourth light guide portion extending in a direction orthogonal to the plane at the tip of each of the third light guide section, the branched plurality Variations in the luminance of the four light guides can be suppressed, and a plurality of display units can be illuminated with uniform luminance by light emitted from one light source. Moreover, since the bridge part which connects the base end sides of both 2nd light guide parts was formed in the branch end of both 1st light guide parts, the center part (1st light guide) of these light guide parts was formed by these bridge parts. The mechanical strength at the branching part) is increased.

  In this case, both the second light guides of the light guide are set to the same length, and the tips of the second light guides are bifurcated to form the third light guide of the same length. In addition, when the fourth light guide portions extending in the direction orthogonal to the plane are formed at the tips of the third light guide portions, the fourth light guide portions are formed at the four corners of the rectangular rectangle in plan view with the light source as the center. Since the tip is positioned, it is preferable that the four display units arranged in two rows in the same plane can be illuminated with uniform luminance by light from one light source.

  In order to achieve the second object described above, a power window switch according to the present invention includes a housing having four openings arranged in two rows and two rows, and a display that is swingably supported in each opening. Mounted with four seesaw knobs having a portion, a plurality of driving bodies that are moved up and down by swinging operation of each of the seesaw knobs, a plurality of switching elements that are operated by these driving bodies, and each of these switching elements and a light source And a light guide body having the above-described configuration disposed between each of the seesaw knobs and the printed circuit board, the light source is disposed at a center position of each of the seesaw knobs, and the light source includes the light source. The light incident part of the light guide is opposed to each other, and the tips of the fourth light guide parts of the light guide are inserted into the openings so as to face the back surface of the seesaw knob.

  According to the power window switch configured as described above, the light incident portion of the light guide configured as described above is opposed to the light source on the printed circuit board at the center position of the four seesaw knobs arranged in two rows. At the same time, the tips of the four fourth light guides branched from the light incident part through the first to third light guides are made to face the back surfaces of the respective seesaw knobs. Using the body, the display portions of the four seesaw knobs can be illuminated with uniform brightness.

In the light guide of the present invention, the second light guide part extending in the opposite direction on the same plane is continuously connected to the tip of the first light guide part branched in a bifurcated manner from the light incident part, and these second light guide parts A plurality of third light guides branched in a direction along the plane with a predetermined radius of curvature from the first part, and a fourth light guide part extending in a direction perpendicular to the plane at the tip of each third light guide Since the bridging portion that connects the base ends of the second light guide portions is formed at the branch ends of the first light guide portions, the amount of light emitted from each fourth light guide portion is emitted from the light source. Thus, the plurality of display portions can be illuminated with uniform luminance by light emitted from one light source. Moreover, since the bridge part which connects the base end sides of both 2nd light guide parts was formed in the branch end of both 1st light guide parts, the center part (1st light guide) of these light guide parts was formed by these bridge parts. The mechanical strength at the branching part) is increased.

  Further, the power window switch of the present invention constitutes an illumination mechanism using such a light guide and one light source, and the light guide is inserted at the center position of four seesaw knobs arranged in two rows. The light portion is made to face the light source on the printed circuit board, and the tips of the four fourth light guide portions branched from the light incident portion through the first to third light guide portions are made to face the back surface of each seesaw knob. Therefore, it is possible to illuminate the display portions of the four seesaw knobs with uniform brightness using one set of light source and light guide.

  An embodiment of the invention will be described with reference to the drawings. FIG. 1 is a perspective view of a light guide according to a first embodiment of the present invention, FIG. 2 is a plan view of the light guide, and FIG. It is sectional drawing which follows the III-III line.

  The light guide 1 shown in these drawings is a molded product made of a light-transmitting resin such as acrylic resin. The light guide 1 includes a first light guide portion 1a, a second light guide portion 1b, and a third light guide. The part 1c is integrally formed with the fourth light guide part 1f. The first light guide portion 1a is bifurcated from the light incident portion 1d with a predetermined radius of curvature, and the end surface of the light incident portion 1d is arranged to face the light source 2 such as an LED or a lamp. . The second light guide part 1b extends in the opposite direction along the plane P (see FIG. 3) parallel to the end face of the light incident part 1d from the tips of the first light guide parts 1a. The length of the optical part 1b is set to the same dimension. The third light guide portion 1c is formed by bifurcating the tips of the second light guide portions 1b into a bifurcated shape with a predetermined radius of curvature along the plane P direction. The thickness of the optical part 1c (the vertical dimension in FIG. 3) is the same in all the parts. The 4th light guide part 1f is four columnar bodies which follow the 3rd light guide part 1c, and these 4th light guide parts 1f are the directions which intersect with the plane P with the predetermined curvature radius from the 2nd light guide part 1b. Extends to the same length. The tip of each fourth light guide portion 1f is arranged to face the display portion 3 provided on the switch operation portion, the display panel or the like, and these fourth light guide portions 1f transmit the light from the light source 2 to each other. It is a light output portion that emits toward the display portion 3. That is, when the light guide 1 is viewed in plan, the light incident portion 1d that faces the light source 2 is located at the center of the virtual rectangle, and the fourth light guide portion 1f that faces each display portion 3 at the four corners of the rectangle. The tip of is to be located. In addition, the branch part 1e which connects the base end sides of both the 2nd light guide parts 1b is formed in the branch end of the 1st light guide part 1a, The center part of the light guide 1 is formed by these bridge parts 1e. The mechanical strength at is increased. Moreover, the curvature radius of the 1st light guide part 1a mentioned above or the 3rd light guide part 1c is a curvature radius of 2-5 times the thickness of the light guide body of radial direction, and there is little light leaking outside. Therefore, light can be guided efficiently.

  In the light guide 1 configured in this way, as shown in FIG. 3, the curvature facing the light source 2 in the first light guide 1 a that bifurcates from the light incident portion 1 d with a predetermined radius of curvature. Since a lot of light is reflected on the outer peripheral side of the light source, the light reflected on the inner peripheral side is less than that on the outer peripheral side, so that the first light guide portion 1a extends in the opposite direction along the same plane P. In the pair of second light guide portions 1b that come out, the brightness difference between the front and back surfaces is large in a region close to the first light guide portion 1a, and the brightness on both front and back surfaces becomes gradually uniform as the distance from the first light guide portion 1a increases. It will become. However, since the front and back surfaces are formed as one third light guide portion in a total of four third light guide portions 1c that branch into a bifurcated shape with a predetermined curvature radius from the tip of each second light guide portion 1b, Compared to the case where the side is a single light guide and the back side is a single light guide, even if the light is branched at a position relatively close to the first light guide portion 1a, variation in luminance between the two can be suppressed. The four display units 3 can be illuminated with uniform brightness by the light emitted from the two light sources 2. That is, each 3rd light guide part 1c branches the front-end | tip of the 2nd light guide part 1b in the surface direction of the plane P, and the 2nd light guide part 1b and the 3rd light guide part 1c are between front and back both surfaces. Since it is configured as one light guide having the same thickness, variations in luminance of the third light guides 1c are suppressed.

  4 is an exploded perspective view of a power window switch according to an embodiment of the present invention, FIG. 5 is a plan view showing the power window switch with the seesaw knob omitted, and FIG. 6 is a cross-sectional view of the main part of the power window switch. is there.

  As shown in these drawings, the power window switch according to the present embodiment is supported in a swingable manner in the upper case 10 having four openings 10a arranged in two rows and columns, and inside each opening 10a. Four seesaw knobs 11, a plurality of drive bodies 12 that are moved up and down by swinging the seesaw knobs 11, a lower case 13 that is integrated with the upper case 10 and forms a housing, and on the lower case 13 A circuit board 14 placed thereon, a rubber sheet 15 attached to the circuit board 14, a light guide 1 according to the first embodiment, and a chip-like LED 16 mounted on the circuit board 14. And an illuminated mechanism.

  Each seesaw knob 11 is swingably supported so that both pull operation and push operation can be performed. On the top surface of each seesaw knob 11, for example, a display portion 11 a indicating an operation direction is formed. The display portion 11a is formed by forming the seesaw knob 11 with a transparent or translucent material and applying an opaque paint or the like to the surface of the surface excluding the display portion 11a. The drive bodies 12 are supported so as to be movable up and down around the respective openings 10 a, and two of these drive bodies 12 are incorporated in one seesaw knob 11. An LED (light source) 16 mounted on the circuit board 14 is located at the center of each seesaw knob 11, and the LED 16 is exposed from a through hole 15 a formed in the rubber sheet 15. Further, the rubber sheet 15 is formed with a plurality of bulging portions 15b, and the lower ends of the respective driving bodies 12 are positioned above the bulging portions 15b. Although not shown, movable contacts are provided on the inner bottom surface of each bulging portion 15b, and a plurality of fixed contacts are provided on the circuit board 14 corresponding to these movable contacts, and these movable contacts and fixed contacts are provided. A plurality of sets of switch elements are constituted by the pairs. The light guide 1 is held on the back surface of the upper case 10 by a fixing means such as snap coupling. As shown in FIG. 6, the light incident portion 1d of the light guide 1 faces the LED 16 and each fourth guide The tip of the optical portion 1 f is inserted into the opening 10 a and faces the back surface of the seesaw knob 11.

  In the power window switch configured as described above, the light incident portion 1d of the light guide 1 is opposed to the LED 16 on the printed circuit board 14 at the center position of the four seesaw knobs 11 arranged in two rows. The tips of the four fourth light guides 1f branched from the light incident part 1d through the first light guide part 1a, the second light guide part 1b, and the third light guide part 1c are made to face the back surfaces of the seesaw knobs 11. Therefore, it is possible to illuminate the display portions 11a of the four seesaw knobs 11 with uniform luminance by using one set of LED (light source) 16 and the light guide 1.

  FIG. 7 is a perspective view of a light guide according to a second embodiment of the present invention, and the same reference numerals are given to portions corresponding to FIGS.

  This embodiment is different from the first embodiment described above in that the four third light guides 1c are branched in the same direction from the proximal end and the distal end of both second light guides 1b in a line. Other than that, the configuration is basically the same. In this case, the length between the two third light guides 1c located outside from the light incident part 1d and the length between the two third light guide parts 1c located inside from the light incident part 1d are slightly different, As described above, in the second light guide portion 1b, the difference in luminance between the front and back surfaces is large in the region close to the first light guide portion 1a, and the luminance on both front and back surfaces becomes gradually uniform as the distance from the first light guide portion 1a increases. Since each of the third light guides 1c has the front and back surfaces as one light guide, the amount of light emitted from the four fourth light guides 1f is almost the same regardless of the difference in branching position. Become.

  In the second embodiment, two third light guides 1c are branched from the base end side and the distal end of one second light guide 1b, and a total of four second light guides 1b are connected to each other. Although the light guide 1 in which the three light guides 1c are branched in a line has been described, the number and branch positions of the third light guides 1c can be changed as appropriate according to the arrangement of the display units 3 that are the objects to be illuminated. For example, the tips of both the second light guides 1b of the light guide 1 shown in FIG. It is good also as the light guide 1 from which the six 3rd light guide parts 1c branch. Further, although depending on the arrangement of the display unit, the fourth light guide unit 1f is not necessarily required, and another light guide may be provided between the fourth light guide unit 1f and the display unit.

1 is a perspective view of a light guide according to a first embodiment of the present invention. It is a top view of this light guide. It is sectional drawing which follows the III-III line of FIG. It is a disassembled perspective view of the power window switch which concerns on the example of embodiment of this invention. It is a top view which abbreviate | omits and shows the seesaw knob of this power window switch. It is principal part sectional drawing of this power window switch. It is a perspective view of the light guide concerning the example of a 2nd embodiment of the present invention. It is a front view of the light guide which concerns on a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light guide 1a 1st light guide part 1b 2nd light guide part 1c 3rd light guide part 1d Light incident part 1e Bridge part 1f 4th light guide part 2 Light source 3 Display part 10 Upper case 10a Opening 11 Seesaw knob 11a Display unit 12 Driver 13 Lower case 14 Circuit board 15 Rubber sheet 15a Through hole 15b Swelling portion 16 LED (light source)
P plane

Claims (3)

A light guide for guiding light emitted from a light source to a plurality of display units, a light incident unit facing the light source, and a first light guide branched from the light incident unit into a bifurcated shape with a predetermined radius of curvature. , A pair of second light guides extending in the opposite direction along the same plane from the first light guides, and the plane direction branched from the second light guides with a predetermined radius of curvature. A plurality of third light guide portions extending along the light source, and a fourth light guide portion extending in a direction orthogonal to the plane at the tip of each third light guide portion, and light emitted from the light source Through the first to fourth light guide parts to the display part ,
A light guide body in which a bridging portion that connects base ends of the second light guide portions is formed at the branch ends of the first light guide portions . 2. The first light guide unit according to claim 1, wherein the second light guide units are set to have the same length, and the ends of the second light guide units are bifurcated to form the third light guide unit having the same length. while, the light guide, wherein the fourth light guide portion extending in a direction orthogonal to the plane at the tip of each of the third light guide section that are formed respectively.   A housing having four openings arranged vertically and horizontally, four seesaw knobs having a display unit supported so as to be able to swing within each opening, and a swing operation of each of the seesaw knobs is moved up and down. A plurality of drive bodies, a plurality of switch elements operated by each of these drive bodies, a printed circuit board on which each of these switch elements and a light source are mounted, and each of the seesaw knobs and the printed circuit board are disposed. The light guide according to Item 2, wherein the light source is disposed at a center position of each seesaw knob, the light incident portion of the light guide is opposed to the light source, and the light guide A power window switch, wherein a tip of each of the fourth light guides is inserted into the opening and is opposed to the back surface of the seesaw knob.

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