JPH0628637U - Instrument - Google Patents

Abstract

(57) [Summary] [Purpose] It is an object of the present invention to provide an instrument in which the brightness of the pointer does not change depending on the rotation angle of the pointer. A meter having a pointer 30 connected to an output shaft of an internal unit and a light guide means (light guide plate) 40 for guiding light from a light source (bulb) 10 to the pointer 30. Has a through hole 41 through which the output shaft passes, and guides the light toward the through hole 41 side.
Second light reflecting surface) 42a, 42b
And has a pointer illumination reflection surface 43 that reflects the light reaching the portion of the through hole 41 toward the pointer 30, and the pointer illumination reflection surface 43 diagonally extends through the through hole 41. It is provided so as to traverse, and the light is emitted from the periphery of the through hole 41 toward the pointer 30.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to an instrument having a structure for illuminating a pointer.

[0002]

[Prior art]

 As an instrument of this type, those shown in FIGS. 5 to 8 are known as those used in speedometers, tachometers and the like. That is, the light from the light bulb (light source) 10 is guided by the light guide plate (light guide means) 20 to the base portion 31 of the pointer 30 to illuminate the pointer 30. The pointer 30 guides the light incident on the base portion 31 to the needle portion 32 and causes the needle portion 32 to emit light. The pointer 30 has a base 31 connected to an output shaft of an internal unit (not shown). The light guide plate 20 has a through hole 21 through which the output shaft passes. The light of the light bulbs 10 located on the left and right is transmitted through the light reflecting surfaces 22 located on both the left and right ends of the through hole 21. The light is guided to the side of the through hole 21 and the left and right reflecting surfaces 23 for pointer illumination provided in the portion of the through hole 21 irradiate the above light to the base 31 of the pointer 30 (however, for the light bulb 10 and the light guide). Only one of the reflecting surfaces 22 is shown).

The light guide reflecting surface 22 and the pointer illuminating reflecting surface 23 are inclined at an angle of approximately 45 degrees with respect to the bottom surface of the base 31 of the pointer 30, and guide the light from the light bulb 10 perpendicularly to the bottom surface. It is like this. The reflecting surfaces 23 for pointer illumination are provided on the left and right sides so as to form a groove having a V-shaped cross section, and the V-shaped combined portion is located at the center of the through hole 21. The reflecting surface 23 for pointer illumination is formed such that its length exceeds the diameter of the through hole 21, and its width extends from the center of the through hole 21 to the edge of the through hole 21. Has been done.

In the instrument configured as described above, since the light of the light bulb 10 can be guided almost perpendicularly to the bottom surface of the base 31 of the pointer 30, the pointer 30 can be efficiently illuminated. .

[0005]

[Problems to be solved by the device]

 However, in the above-mentioned conventional instrument, as shown in FIG. 7, almost all of the light guided to the portion of the reflecting surface 23 for pointer illumination that exceeds the diameter of the through hole 21 is reflected by the base portion 31 of the pointer 30. However, the light guided to the part within the diameter of the through hole 21 has a small area for the reflecting surface 23 for reflecting the pointer, so that the amount of light reflected by the base portion 31 of the pointer 30 is small, and further, the center of the through hole 21. As shown in FIG. 8, the light guided to is not reflected by the base 31 because the reflecting surface 23 for reflecting the pointer is lost. Therefore, the amount of light incident on the base 31 of the pointer 30 varies depending on the circumferential position of the through hole 21, and when the pointer 30 rotates, the brightness of the pointer 30 changes depending on the rotation angle. there were.

The present invention has been made in order to solve the above-mentioned problems, and an object thereof is to provide an instrument in which the brightness of the pointer does not change depending on the rotation angle of the pointer.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention is an instrument provided with a pointer provided on an output shaft of an internal unit and a light guide means for irradiating the pointer with light guided from a light source, wherein the light guide means is , A reflection for pointer illumination that has a light-reflecting surface that reflects the light from the light source toward a through hole that penetrates the output shaft, and that reflects the light reflected toward the through hole toward the pointer The reflecting surface for illuminating the pointer has a surface around the through hole so as to traverse the through hole so that the light reflected from the reflecting surface for guiding the light is reflected toward the pointer. The light guide reflection surface is formed obliquely, and reflects the light from the light source toward the left and right outer portions of the through hole and the inner portion obliquely extending from the through hole in the pointer illumination reflection surface. Characterized by being designed to That.

[0008]

In the illumination structure of the instrument configured as described above, the light from the light source reaches the pointer illumination reflection surface from the light guide reflection surface, and further reaches the pointer from the pointer illumination reflection surface. Since the reflecting surface for pointer illumination is formed so as to cross the through hole, and the reflecting surface for pointer illumination is located so as to surround the periphery of the through hole, the portion outside the through hole of the reflecting surface for pointer illumination is located. The light that reaches the point also reaches the inside of the through hole and reflects toward the pointer. Therefore, the amount of light incident on the pointer becomes substantially constant over the circumferential direction of the through hole, so that the brightness of the pointer does not change depending on the rotation angle.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. However, elements common to those shown in FIGS. 5 to 8 are given the same reference numerals to simplify the description. The instrument shown in FIGS. 1 to 4 differs from the instrument shown in FIGS. 5 to 8 in that the structure of the light guide plate (light guide means) 40 is different.

That is, as shown in FIG. 1, the base portion 31 of the pointer 30 is connected to, for example, an output shaft (not shown) of an internal unit that detects the speed of the vehicle, and the light guide plate 40 has the above-mentioned output portion. A through hole 41 through which the force shaft penetrates is formed. The light guide plate 40 is made of a transparent material such as acrylic resin and has a plate shape, and has the through hole 41 substantially at the center in the longitudinal direction. The left and right ends of the light guide plate 40 are bent at a right angle in a U-shape, and the left and right bends allow the light from the bulbs (light sources) 10 arranged on the left and right to pass through the through hole 41. A first light-reflecting surface 42a and a second light-reflecting surface 42b for guiding are formed. Further, the light guide plate 40 has a pointer illumination reflection surface 43 that reflects the light guided from the left and right to the through hole 41 side to the base 31 of the pointer 30, and a surface that opposes the base 31 of the pointer 30. Further, it has a disk-shaped convex portion 44 coaxial with the through hole 41.

As shown in FIGS. 2 and 4, the first light-reflecting surface 42 a is formed substantially at the center in the width direction of the light guide plate 40 and has a width substantially equal to the diameter of the through hole 41. And is inclined so as to irradiate light mainly on the lower side (counter pointer 30 side) of the reflecting surface 43 for finger illumination. As shown in FIGS. 2 and 3, the second light-reflecting surface 42b is formed on both sides of the first light-reflecting surface 42a and is located outside the through-hole 41. It is tilted so as to irradiate light mainly on the upper side (the side of the pointer 30) of 43.

As shown in FIGS. 2 to 4, the reflecting surfaces 43 for pointer illumination are provided on the left and right so as to form a groove having a V-shaped cross section on the lower surface of the light guide plate 40, and are combined in a V-shaped manner. The open portion is located at the center of the through hole 41. The reflecting surface 43 for pointer illumination is formed such that its length exceeds the diameter of the through hole 41, and its width extends from the center of the through hole 41 to the outer edge of the convex portion 44. ing. That is, the left and right pointer illumination reflecting surfaces 43 are formed obliquely so as to traverse the through hole 41, and always exist around the through hole 41.

The convex portion 44 is formed to have substantially the same diameter as the bottom surface of the base portion 31 having a circular cross section. Further, in the light guide plate 40, the first light-reflecting surface 42a guides light mainly to the lower side of the pointer illumination reflecting surface 43, and the second light-reflecting surface 42b mainly guides the pointer illumination reflecting surface 43. Since the light is guided to the upper side, it is possible to form the left and right end portions to be thin and to gradually increase the thickness from the bent portion toward the pointer illumination reflecting surface 43.

In the instrument configured as described above, the light emitted from the light bulb 10 on the left and the light on the right are respectively transmitted from the first light-reflecting surface 42a and the second light-reflecting surface 42b located on the left and right, respectively. It reaches the reflecting surface 43 for pointer illumination, and further reaches the base 31 of the pointer 30. The light that has reached the first light-reflecting surface 42a is guided mainly to a lower portion of the pointer illumination reflecting surface 43 inside the through hole 41, and is reflected toward the base 31 side of the pointer 30. Therefore, light is emitted from the central portion of the light guide plate 40, which is the diameter width portion of the through hole 41, to the base portion 31 of the pointer 30. Further, the light reaching the second light-guiding reflecting surface 42b is guided mainly to the upper portion of the pointer-illuminating reflecting surface 43 outside the through-hole 41, and is reflected toward the base 31 side of the pointer 30. Therefore, light is emitted from the outside of the through hole 41 to the base 31 of the pointer 30. Therefore, the amount of light entering the base portion 31 of the pointer 30 from the left and right pointer illumination reflecting surfaces 43 becomes substantially uniform in the circumferential direction of the through hole 41.

According to the instrument configured as described above, the amount of light incident on the base portion 31 of the pointer 30 becomes substantially uniform over the circumferential direction of the through hole 41, so that even if the rotation angle of the pointer 30 changes. The brightness of the needle portion 32 of the pointer 30 will not change. Further, the left and right ends of the light guide plate 40 can be formed thin, and the light guide plate 40 can be formed so that the thickness gradually increases from the bent portion toward the pointer illumination reflection surface 43. Is effective in reducing the cost and the cost.

In the above embodiment, two types of light reflecting surfaces 42a and 42b are provided. However, one light reflecting surface is used to reflect light on the entire pointer illuminating reflecting surface 42. You may make it provide only.

[0017]

[Effect of device]

 According to this invention, the reflecting surface for pointer illumination is provided so as to cross the through hole, and the reflecting surface for pointer illumination is positioned so as to surround the through hole. The light that reaches the outer portion of the through hole can also be reflected toward the pointer when it reaches the inner portion of the through hole. Therefore, the amount of light incident on the pointer can be made substantially uniform in the circumferential direction of the through hole, and the brightness of the pointer can be prevented from changing depending on the rotation angle.

[Brief description of drawings]

FIG. 1 is a perspective view of an instrument shown as an embodiment of the present invention.

FIG. 2 is a plan view showing a light guide plate of the instrument.

FIG. 3 is a sectional view taken along the line III-III in FIG.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a perspective view of an instrument shown as a conventional example.

FIG. 6 is a plan view showing a light guide plate of the instrument.

7 is a sectional view taken along line VII-VII of FIG.

8 is a sectional view taken along the line VIII-VIII in FIG.

[Explanation of symbols]

 10 Light Source (Light Bulb) 30 Pointer 40 Light Means (Light Guide Plate) 41 Through Hole 42a Light Reflection Surface (First Light Reflection Surface) 42b Light Reflection Surface (Second Light Reflection Surface) 43 Point Light Reflection surface

Claims (1)

[Scope of utility model registration request] 1. An instrument comprising a pointer provided on an output shaft of an internal unit and a light guide means for irradiating the pointer with light guided from a light source, wherein the light guide means penetrates through the output shaft. While having a light-reflecting surface for reflecting light from the light source toward the through hole, and having a pointer illumination reflecting surface for reflecting the light reflected toward the through hole toward the pointer, The pointer illumination reflective surface is formed obliquely around the through hole so as to traverse the through hole so as to reflect the light reflected from the light guide reflective surface toward the pointer, and The light guide reflection surface reflects light from the light source toward the left and right outer portions of the through hole and the inner portion obliquely extending from the through hole in the pointer illumination reflection surface. Characteristic instrument.