JP3670141B2 - Light leakage prevention structure for switch illumination light - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an illumination light leakage prevention structure for a switch provided with a light emitting display portion for emitting and displaying a peripheral portion of an operation switch installed in an automobile, for example, and in particular, the illumination light leakage prevention structure is simplified and economical. The present invention relates to a light leakage prevention structure for switch illumination light, which has a structure capable of enhancing the performance and effectively preventing light leakage from the periphery of the operation switch.
[0002]
[Prior art]
FIG. 3 shows a multi-display device (vehicle information display device) installed in front of the driver's seat of an automobile. The multi-display device has a display 2 at the center of the rising surface of the housing 1 and a right-hand side thereof. A joystick type switch structure 3 is provided, and operation knobs 4 of the operation switches are arranged on the horizontal plane of the housing 1.
[0003]
As shown in FIGS. 4 and 5, the internal configuration of the joystick-type switch structure 3 includes a printed circuit board 6 that is attached to the housing 1 from the back side of the housing 1 with a mounting screw 5. A joystick-type switch body 8 having an operation shaft 7 that can be operated in the three-dimensional direction of up, down, left, right, and back and forth, and a plurality of light sources 9 for transmitting and illuminating a lighting unit to be described later are disposed and supported. Since the internal configuration of the joystick-type switch body 8 is a well-known structure, description of the internal configuration of the switch body 8 is omitted.
[0004]
Reference numeral 10 denotes a switch operation knob having a skirt portion 11 having a substantially hemispherical cross section attached to the operation shaft 7, and the light from the light source 9 is received around the switch operation knob 10 and the joystick type switch body 8. An annular light guide 12 having a light receiving surface 12A is positioned. An annular illumination lens 14 having a light emitting illumination unit 13 is brought into contact with an end surface (light emitting surface 12B) of the light guide 12, and the illumination lens 14 is a switch operation hole 15 provided in the housing 1. Each of the light emitting illumination sections 13 is inserted into an illumination lens fitting section 16 formed in the periphery of each of the display holes formed in the illumination lens fitting section 16 provided in the housing 1. 17 is seen through. Further, an annular light shielding member 18 is fitted on the inner peripheral surface of the light guide 12 and the inside of the lamp 9 so that light leakage from the switch operation hole 15 is prevented.
[0005]
In the conventional joystick-type switch structure 3 having such a configuration, when the display hole 17 for displaying the operation direction of the switch operation knob 10 is provided around the switch operation hole 15 and the lamp 9 is turned on. The light emitted from the light source 9 can be emitted and displayed by the light emitting illumination unit 13 via the light guide 12 and the illumination lens 14. Further, the light shielding member 18 positioned inside the light source 9 and the light guide 12 prevents the light of the lamp and the light guide 12 from leaking from the switch operation hole 15, thereby improving the display quality. Yes.
[0006]
[Problems to be solved by the invention]
However, in such a conventional joystick type switch structure, as a means for preventing leakage of the lamp light from the switch operation hole 15 when the light source 9 is lit, resin molding is performed in an annular shape by injection molding. The expensive light-shielding member 18 must be disposed between the switch operation unit knob 10 and the light source 9 and the light guide 12. This causes a joystick switch having a light-emitting illumination unit to be expensive and not economical. Met. Further, in the conventional joystick switch 3, since the light guide 12, the illumination lens 14, and the light shielding member 18 formed as separate members are used in combination, the number of parts used increases. There was also a problem that assembly workability and productivity deteriorated.
[0007]
The present invention has been made by paying attention to such a conventional problem, and a light-shielding member used for preventing light leakage from the switch operation hole is an elastic foam which is inexpensive and excellent in assembling workability of the switch structure. The first object is to improve the economics of the light leakage structure in the switch device having the illumination means by using the body.
[0008]
A second object of the present invention is to improve the assembly workability of a switch structure having a light leakage prevention structure by reducing the number of components constituting a light emitting display mechanism for displaying light around the switch.
[0009]
[Means for Solving the Problems]
The invention for achieving the first and second objects includes a switch body mounted on a printed circuit board disposed on a bottom surface of a housing case, a skirt portion having a substantially hemispherical cross section, and A switch operating knob that protrudes outward from the switch operating hole of the housing case, and an inner surface that maintains a predetermined distance from the outer surface of the skirt of the switch operating knob. And an annular guide light having one end surface as a light emitting surface for emitting and displaying the periphery of the switch operation hole and the other end surface as a light receiving surface, and a light source disposed in the vicinity of the light receiving surface of the annular guide light; In the joystick type switch comprising: an annular light-shielding elastic foam that shields a gap between the outer surface of the skirt portion of the switch operation knob and the inner surface of the annular light guide; An elastic restoring force possessed by the light-shielding elastic foam so as to surround the switch body is such that one end face of the light-shielding elastic foam is on the printed circuit board and the other end is on the skirt edge of the switch operation knob and the light guide. The switch illumination light leakage prevention structure is characterized in that the pressure illumination is held in an elastic manner to prevent leakage of direct light from the light source emitted to the outside of the switch structure through the gap.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below based on the first embodiment shown in FIG.
[0012]
A joystick type switch structure 21 shown in FIG. 1 is installed in the vehicle information display shown in the conventional example, for example. The internal configuration of the joystick type switch structure 21 is from the back side of the housing case 22. The printed circuit board 23 is attached to the housing case 22, and the printed circuit board 23 has an operation shaft 24 that can be operated in three-dimensional directions, up and down, right and left, and front and rear. A certain joystick-type switch body 25 and a plurality of light sources 26 arranged around the joystick-type switch body 25 are arranged and supported.
[0013]
Reference numeral 27 denotes a switch operation knob having a skirt portion 28 having a substantially hemispherical cross section attached to the operation shaft 24. An annular light guide 31 formed of a transparent acrylic resin is disposed. The light guide 31 is fitted into a light receiving surface 31A for receiving light from the light source 26 and light emitting display holes 30 formed at four positions around a switch operation hole 29 formed in the housing case 22. A light emitting surface 31B.
[0014]
An annular (doughnut-shaped) light-blocking elastic foam 32 is interposed between the printed circuit board 23 and the periphery of the skirt portion 28 of the switch operating knob 27. The joystick is placed inside the light-blocking elastic foam 32. A mold switch body 25 is disposed, and the light source 26 is disposed outside the light shielding elastic foam 32. Further, the light-shielding elastic foam 32 is designed to block the gap (a) generated between the outer peripheral surface of the skirt portion 28 of the switch operation knob 27 and the inner peripheral surfaces of the switch operation hole 29 and the light guide 31. The guide 31 is also in pressure contact with the inner peripheral surface.
[0015]
The light-shielding elastic foam 32 is made of an ethylene / propylene-based sponge having excellent heat resistance, weather resistance, and the like. For example, a dark-colored or black-colored eptosealer (product of Nitto Denko Corporation) Product name) No. 685 is preferably used, but is not limited to this material, and a resin foam (sponge-like one) having flexible elasticity can be selected and used as appropriate. The size of the light-blocking elastic foam 32 can be determined according to the shape and size of the joystick-type switch structure 21, and the material can be selected and used according to the use environment.
[0016]
In order to assemble the light-shielding elastic foam 32 into the joystick-type switch structure 21, the bonding surface of the light-shielding elastic foam 32 and the printed circuit board 23 is bonded using, for example, an adhesive tape or an adhesive, When the assembly of the joystick-type switch structure 21 is completed, the light-shielding elastic foam 32 has a maximum of the light-shielding elastic foam 32 between the edge of the skirt portion 28 of the switch operation knob and the printed circuit board 23. The gap (a) is completely shielded by the light-shielding elastic foam 32 in a close contact (compressed) state that is compressed and deformed to about 20% of the amount of elastic deformation. ) Is set so as not to leak out of the case 22.
[0017]
The above is the first embodiment. Next, the operation thereof will be described. When the light source 26 is turned on, the light emitted by the light source 26 is received by the light receiving surface 31A of the light guide 31, and this light guide. Light emission is displayed on the four light emitting surfaces 31B. At this time, the light emitted from the light source 26 does not leak out of the case 22 through the gap (a) due to the shielding action by the light shielding elastic foam 32, neither direct light nor reflected light from the housing case 22 and the printed circuit board. Therefore, it is a joystick type switch structure having a good light shielding property.
[0018]
The light guide 31 has an integrated structure having a light receiving surface 31A of the light source 26 and a light emitting surface 31B that emits and displays light on the outer surface of the case 22, that is, two members of the light guide and the illumination lens described in the conventional example. Therefore, the number of parts used for assembly of the joystick type switch structure can be reduced.
[0019]
Furthermore, since the joystick type switch body 25 is surrounded by the light-shielding elastic foam 32 and the switch operation knob 27, the operation sound generated during the switch operation of the joystick type switch body 25 is not easily released to the outside of the housing case 22 and is quiet. It is possible to provide a switch that is excellent in performance.
[0020]
FIG. 2 shows a second embodiment of the present invention. In the second embodiment, the light guide 33 formed in an annular shape has a light receiving surface 31A and a light emitting surface 31B. The light emitting surface 34B fitted into the light emitting display holes 30 formed at the four positions around the light receiving surface 34A that contacts the light emitting surface 31B of the light guide and the switch operation hole 29 formed in the housing case 22. In combination with an illumination lens 34 having
[0021]
Then, the light-blocking elastic foam 32 is elastically pressed in the same manner as in the above-described embodiment so as to close the gap formed between the outer peripheral surface of the skirt portion 28 of the switch operation knob 27 and the switch operation hole 29 and the light guide 33. Is touching. Other configurations are the same as in the first embodiment.
[0022]
Thus, by configuring the light guide 33 with the light guide main body 31 and the illumination lens 34, for example, the light guide main body 31 can be formed of a transparent acrylic resin so that the light guide efficiency can be increased. By forming the lens 34 with an acrylic resin colored in blue, green, orange, or the like or having a smoke tone, it is possible to perform color display without significantly reducing the luminance.
[0023]
【The invention's effect】
As described above, according to the joystick-type switch structure of the present invention, light is transmitted to the outside of the switch structure by the annular light-shielding elastic foam interposed in close contact between the printed circuit board and the switch operation knob. Since leakage can be effectively prevented, the economics of the light shielding structure is greatly improved. Also since no integral structure serving as a light guide and an illumination lens, is reduced using number of components, which assembling workability and economy of the joystick type switch structure is enhanced by.
[0024]
Further, since the switch operation knob skirt is always pressed against the light-blocking elastic foam, the impact force is absorbed by the light-blocking elastic foam when the switch operation knob is bounced, and the joystick-type switch body. Is surrounded by an annular light-shielding elastic foam, so that a joystick type switch structure excellent in quietness can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of a switch illumination light leakage prevention structure according to the present invention.
FIG. 2 is a sectional view showing a second embodiment of a switch illumination light leakage prevention structure according to the present invention.
FIG. 3 is a perspective view of a vehicle information display device provided with a joystick switch having a switch illumination mechanism.
FIG. 4 is an exploded perspective view of a joystick switch having a conventional switch illumination mechanism.
FIG. 5 is a cross-sectional explanatory view of a joystick type switch having a conventional switch illumination mechanism.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 21 ... Joystick type switch structure 22 ... Housing case 23 ... Printed circuit board 24 ... Operation axis 25 ... Joystick type switch body 26 ... Light source 27 ... Switch operation knob
27A ... Pinch 28 ... Skirt 29 ... Switch operation hole 30 ... Light emitting display hole 31 ... Light guide (light guide body)
32 ... Light-shielding elastic foam 33 ... Light guide 34 ... Illumination lens
a ... Gap

Claims (1)

A switch body mounted on a printed circuit board disposed on the bottom surface of the housing case;
A switch operation knob having a skirt portion having a substantially hemispherical cross section and a knob, the knob protruding outward from the switch operation hole of the housing case;
An annular guide having an inner surface maintaining a predetermined distance from the outer surface of the skirt portion of the switch operation knob, and having one end surface as a light emitting surface for emitting and displaying the periphery of the switch operation hole and the other end surface as a light receiving surface. With lights,
A light source disposed in the vicinity of the light receiving surface of the annular guide light;
In the joystick type switch consisting of
The light-shielding elastic foam has an annular light-shielding elastic foam that shields the gap between the outer surface of the skirt portion of the switch operating knob and the inner surface of the annular light guide so as to surround the switch body. One end face of the light-blocking elastic foam is elastically restored to the printed circuit board and the other end face is held in pressure contact with the edge of the skirt portion of the switch operation knob and the light guide, and the switch structure passes through the gap. A light leakage prevention structure for switch illumination light, wherein leakage of direct light from the light source emitted to the outside of the body is prevented.

Images