JP2010243253A - Light guide, and display device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form compactly a light entrance part for guiding light from a light source to a body part of a light guide. <P>SOLUTION: A ring light guide 3 used for illumination of a vehicle instrument includes a guide body part 31 formed circularly. The guide body part 31 is divided into three light guide parts 33, 33, 33 in the circumferential direction. Each light guide part 33 having an inclined rear surface 33b so that the thickness becomes thinner gradually toward one side in the circumferential direction, guides light entering from the thicker base end side to the thinner tip side, simultaneously reflects the light by the rear surface 33b, and emits the light from the front surface 33a. A space S is formed on the rear side of the tip part of each light guide part 33, by tilting of the rear surface 33b of the light guide part 33. The light entrance part 32 for guiding light from the light source 12a to the light guide part 33 is extended from the base end of each light guide part 33 through a rear side space S of another light guide part 33 adjacent to the other side in the circumferential direction relative to the light guide part 33. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a light guide used for illumination of a vehicle instrument and a vehicle display device including the same.

  Conventionally, various illuminating devices have been adopted for vehicle display devices, thereby improving the visibility of instruments and improving the aesthetics.

  For example, in the vehicle display device according to Patent Document 1, a light guide is provided on the back side of the dial, and the dial is made to emit light from the light source to the front side through the light guide. Illuminated from the back side.

  Specifically, the light guide disclosed in Patent Document 1 is formed in an arc shape. Further, the back surface of the light guide body is inclined so that the thickness of the light guide body is the thickest at both end portions in the circumferential direction and gradually decreases from both end portions toward the center portion in the circumferential direction. Two light sources are provided at both ends of the light guide configured as described above so as to face the respective end faces. Light from the light source enters the light guide from both end faces of the light guide, reflects off the back surface of the light guide while propagating in the circumferential direction in the light guide, and exits from the surface of the light guide. In this way, the dial on the surface side of the light guide is illuminated.

JP 2000-18976 A

  As described above, in the light guide that emits light to the front surface side, when the light source is arranged on the back side of the light guide, the portion corresponding to the light source becomes particularly bright and color unevenness occurs. Therefore, light from the light source is incident from the circumferential end face of the light guide so that the light guide and the light source do not overlap when the light guide is viewed from the front side. Specifically, a light source is disposed on the extended line of the light guide at both ends of the light guide, and light is incident in the circumferential direction from both circumferential end surfaces of the light guide. When light is incident from the circumferential end face of the light guide, the light source is arranged at a position that does not overlap the light guide when the light guide is viewed from the front side, and the light from the light source is guided. It is possible to easily realize a configuration for entering the light.

  However, when light is incident on the light guide from a portion other than the circumferential end face of the light guide, it is necessary to devise the configuration of the light guide. Specifically, when light is incident on the light guide from a portion other than the circumferential end face of the light guide, for example, the light source is positioned so as not to overlap the light guide when the light guide is viewed from the front side. It is necessary to extend the light incident part for guiding the light from the light source to the main body part of the light guide to the light source from the main body part of the light guide part.

  The light incident portion is a portion where light from the light source is incident, and the incident light is hardly attenuated, and thus is relatively bright. In particular, the incident surface and the vicinity thereof in the light incident portion become brighter. Therefore, from the viewpoint of suppressing color unevenness of the main body portion of the light guide, it is preferable to secure a certain length of the light incident portion. In other words, if the distance from the incident surface of the light incident portion to the main body is too short, the strong light just incident from the incident surface will immediately propagate into the main body, and color unevenness will occur in the vicinity of the incident surface of the main body. Will occur.

  In this way, when the light source is arranged at a position that does not overlap with the main body of the light guide, and the incident surface of the light incident portion is configured to be separated from the main body to some extent, the light incident portion deviates from the main body, It protrudes from the main body.

  By the way, in the display apparatus for vehicles etc. in which a light guide is used, the space for arranging the light guide is limited. Therefore, in the case where the light incident part protrudes beyond the main body part, in order to arrange the entire light guide including the light incident part in the limited space, the main body part must be made smaller or It is necessary to arrange the light guide so that the optical part does not interfere with other members, and there are various design restrictions. In other words, the greater the amount of protrusion of the light incident portion from the main body portion, the lower the design freedom of the light guide and the vehicle display device.

  The technology disclosed herein has been made in view of such a point, and an object thereof is to compactly form a light incident portion that guides light from a light source to a main body portion of a light guide.

  The light guide disclosed here is a light guide used for illumination of an instrument for a vehicle, and includes a main body formed in an annular shape or an arc around a predetermined axis. The light guides are divided into a plurality of light guides, and each light guide has a front surface and a back surface facing each other in the axial direction, and the back surface is thinned so that the thickness in the axial direction decreases toward one of the circumferential directions. Inclined and configured to reflect light incident from the thick proximal end side to the thin distal end side and to be reflected from the back surface to be emitted from the front surface. A space is formed on the back side of the light guide portion by inclining the back surface of the light guide portion, and a light incident portion for guiding light from the light source to the light guide portion is provided from the base end portion of each light guide portion. The light guide extends through the space on the back side of another light guide adjacent to the other side in the circumferential direction with respect to the light guide. And the.

  In the case of the above configuration, the main body portion of the light guide is divided into a plurality of light guide portions in the circumferential direction, and the back surface is inclined so that each light guide portion gradually becomes thinner toward one side in the circumferential direction. . In this way, the back surface of the light guide unit functions as a reflection surface. As a result of such a configuration, in the light guide portion adjacent in the circumferential direction, the other distal end portion is connected to one proximal end portion. Since the base end portion and the tip end portion have different thicknesses, a step is formed at the boundary between two adjacent light guide portions. In other words, the back surface of the distal end portion of each light guide portion is raised to the front surface side than the back surface of the proximal end portion of the adjacent light guide portion, and a space is formed on the back side of the distal end portion.

  And the light-incident part for guiding the light from a light source to each light guide part is arrange | positioned using this space. Specifically, a light incident part for guiding light incident from a light source to the light guide part is connected to a base end part of each light guide part, and the light incident part is arranged to extend through the space. Yes.

  In other words, as a result of inclining the back surface of the light guide section to form a reflection surface, the light entrance section is made compact by providing a light entrance section using the space formed on the back side of the tip portion of the light guide section. Can be formed. That is, when viewed in the axial direction, the main body portion and a part of the light incident portion overlap each other. Therefore, it is possible to form the light incident portion in a compact manner as compared with a configuration in which the light incident portion is simply connected to the outer peripheral surface of the main body portion and extends so as to be deviated from the outer peripheral surface to the outside of the main body portion. it can.

  Further, another light guide disclosed herein is a light guide used for illumination of a vehicle meter, and includes a main body formed in an annular shape around a predetermined axis. It has front and back surfaces that face each other in the axial direction, and the thickness in the axial direction gradually decreases from a predetermined base end toward one side in the circumferential direction, and becomes the thinnest at the front end that returns to the base end. Further, the back surface is inclined, and is configured to reflect the light incident from the base end portion in the circumferential direction and to reflect the light from the back surface and to emit the light from the front surface. A space is formed by inclining the back surface, and a light incident part for guiding light from a light source to the main body part extends through the space on the back side of the tip part from the base end part. Shall.

  In the case of the above configuration, the back surface of the annularly formed main body is inclined so that the thickness gradually decreases from the predetermined base end portion along the circumferential direction, so that the back surface functions as a reflection surface. ing. As a result of this configuration, the distal end portion, which is the portion of the main body portion that has made a round in the circumferential direction from the proximal end portion and returned to the proximal end portion, is thinner than the proximal end portion. Thus, a step is formed at the boundary between the proximal end portion and the distal end portion. That is, the back surface of the front end portion is raised to the front surface side than the back surface of the base end portion, and a space is formed on the back side of the front end portion.

  And the light-incidence part for guide | inducing the light from a light source to the main-body part is arrange | positioned using this space. Specifically, a light incident part for guiding light incident from the light source to the light guide part is connected to the base end part, and the light incident part is arranged to extend through the space. By doing so, when viewed in the axial direction, the main body portion and a part of the light incident portion overlap each other. Therefore, the light incident portion can be formed more compactly compared to the configuration in which the light incident portion extends from the outer peripheral surface of the main body portion so as to be deflected to the outside of the main body portion.

  According to this light guide, the light incident part can be formed in a compact manner by providing the light incident part using the space formed by inclining the back surface of the main body part.

It is a disassembled perspective view of the display apparatus for vehicles concerning the embodiment of the present invention. It is a front view of the display apparatus for vehicles. It is a perspective view of a ring light guide. It is a top view of a ring light guide. It is a front view of a ring light guide. It is a perspective view of a case. It is the figure which expand | deployed the ring light guide mainly used for the case in planar shape. It is a perspective view of the ring light guide concerning other embodiments.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view of a vehicle display device, and FIG. 2 is a front view of the vehicle display device.

  The vehicle display device 1 according to the embodiment of the present invention includes a vehicle meter such as a speedometer that displays the speed of the vehicle, a tachometer that displays the engine speed of the vehicle, and a fuel gauge that displays the remaining amount of fuel. Is provided. As shown in FIG. 1, the vehicle display device 1 includes a rear case 11, a printed board 12, a case 4, a ring light guide 3, a dial 13, hands 14, 14,. A panel control shaft 15b, a wind plate 16, a front acrylic 17, a meter panel 18, and a ring 19 are provided.

  The printed board 12 is a board on which electronic components such as a light source 12 a (see FIGS. 2 and 7) are mounted, and is sandwiched between the rear case 11 and the case 4. The light source 12a is composed of, for example, an LED.

  The case 4 is for reflecting or blocking light from the light source 12a when the dial 13 is illuminated by the light source 12a. Specifically, the case 4 is provided with a space for disposing the ring light guide 3 and other light guides, and a dial 13 is disposed on the front surface of the case 4. And the light from the light source 12a arrange | positioned at the back side of case 4 is guide | induced to the dial 13 via light guides, such as this ring light guide 3. FIG. A detailed configuration of the case 4 will be described later.

  The dial 13 is drawn with necessary numbers, scales, figures, etc. according to the speedometer, tachometer and fuel gauge. Specifically, the dial 13 is formed of a translucent resin, for example, a colorless and transparent polycarbonate resin or an acrylic resin. The dial 13 is entirely painted black or formed with a black film, and is basically configured not to transmit light. Numbers, scales, figures, and the like are drawn in a slit shape on a black paint or film, and the dial 13 is configured to transmit light only in the portions on which the numbers and the like are drawn. Furthermore, by coloring the slit-like portion on which the numbers and the like of the dial 13 are drawn, the numbers and the like can be emitted in a desired color.

  Specifically, in the area 13A corresponding to the speedometer in the dial 13, as shown in FIG. 2, a scale 13a representing the vehicle speed, a number 13b representing the speed corresponding to the scale, a vehicle speed unit 13c, The ring-shaped slit 13d for illuminating the outer peripheral edge of the region 13A corresponding to the speedometer is configured to transmit light. In addition, the scale 13a, the number 13b, and the unit 13c may be configured so as not to transmit light only by being drawn on a black paint or film.

  On the surface of the dial 13, a pointer 14 is provided at a predetermined position corresponding to a speedometer, a tachometer, or a fuel gauge. The pointer 14 is attached to a drive shaft extending from a movement provided on the printed board 12, and is driven to rotate by the movement.

  The trip shaft 15a is an operation unit for switching or resetting the odometer / trip meter. The panel controller shaft 15 b is an operation unit that adjusts the brightness of illumination such as a meter in the vehicle display device 1. The base end portions of the trip shaft 15a and the panel control shaft 15b are inserted into the case 4. Further, the tip end portions of the trip shaft 15a and the panel control shaft 15b penetrate the window plate 16 and the front acrylic 17, and are exposed to the outside from the front acrylic 17, and can be operated by the user.

  The wind plate 16 is attached to the surface of the case 4. At this time, the wind plate 16 sandwiches the dial 13 with the case 4. The wind plate 16 includes partition walls 16a and 16a that divide the dial 13 into predetermined regions corresponding to a speedometer, a tachometer, and a fuel gauge. That is, the dial 13 is divided by the wind plate 16 into a speedometer area 13A, a tachometer area, and a fuel gauge area.

  A front acrylic 17 is provided on the surface of the wind plate 16. The front acrylic 17 prevents dust from entering the space defined by the dial 13 and the wind plate 16.

  A meter panel 18 is provided on the surface of the front acrylic 17. The meter panel 18 is a member for decoration of the vehicle display device 1. The meter panel 18 has partition walls 18a and 18a, similarly to the window plate 16, and functions as a partition for a speedometer, a tachometer, and a fuel gauge.

  The ring 19 is provided on the surface of the meter panel 18. Similarly to the meter panel 18, the ring 19 is a member for decoration of the vehicle display device 1.

  Hereinafter, the ring light guide 3 will be described in detail with reference to FIGS. 3 is a perspective view of the ring light guide 3, FIG. 4 is a plan view of the ring light guide 3, and FIG. 5 is a front view of the ring light guide 3.

  The ring light guide 3 has an annular guide main body 31 and three light incident portions 32, 32, 32 provided on the guide main body 31. The ring light guide 3 is formed of a translucent material, for example, a colorless and transparent polycarbonate resin or acrylic resin. The ring light guide 3 constitutes a light guide, and the guide main body 31 constitutes a main body.

  The guide main body 31 is formed in an annular shape around a predetermined central axis X. In addition, the guide main body 31 is equally divided into three in the circumferential direction, and each of the divided parts constitutes the light guide 33. That is, the guide main body 31 is composed of three light guides 33, 33, 33. The surfaces 33a, 33a, 33a of the three light guide portions 33, 33, 33 are connected to each other in a flush state to form one annular plane. On the other hand, the back surfaces 33b, 33b, and 33b of the three light guide portions 33, 33, and 33 are not flush with each other and are configured as separate surfaces.

  Specifically, the back surface 33b of each light guide portion 33 is inclined so as to gradually approach the surface 33a from one end portion in the circumferential direction toward the other end portion. Thus, each light guide portion 33 gradually decreases in thickness (dimension in the central axis X direction) from one end portion in the circumferential direction toward the other end portion (that is, clockwise in FIGS. 3 and 4). Yes. Hereinafter, in each light guide section 33, the side with the smallest thickness is defined as the distal end side, and the side with the largest thickness is defined as the proximal end side. In the light guide portions 33 and 33 adjacent to each other in the circumferential direction, the base end portion of the other light guide portion 33 is connected to the distal end portion of the one light guide portion 33. In the two adjacent light guides 33 and 33, the back surface 33b of the distal end portion of the other light guide portion 33 is raised to the front surface 33a side than the back surface 33b of the base end portion of the one light guide portion 33, A space S is formed on the back side of the distal end portion of the light guide portion 33.

  A light incident portion 32 is connected to the base end portion of each light guide portion 33. Specifically, the light incident portion 32 extends in the tangential direction of the guide main body portion 31 from the base end portion of each light guide portion 33 through the space S on the back side of the distal end portion of the adjacent light guide portion 33. Further, the light incident portion 32 extends so as to taper toward the tip in the thickness direction. Specifically, the back surface 32 b of the light incident part 32 extends substantially parallel to the surface 33 a of the adjacent light guide part 33, while the surface 32 a of the light incident part 32 is adjacent toward the tip of the light incident part 32. The light guide 33 extends at an angle so as to be away from the surface 33a.

  Here, the light incident part 32 does not extend so long, and a part of the tip surface 32 c of the light incident part 32 is located in the space S. That is, when viewed in the direction of the central axis X (that is, when viewed from the direction orthogonal to the surface 33 a serving as the emission surface), most of the front end surface 32 c of the light incident portion 32 is larger than the guide main body portion 31. Although protruding outward in the radial direction, a part of the tip surface 32c overlaps the guide main body 31 (specifically, the tip of the adjacent light guide 33).

  Next, the arrangement structure of the ring light guide 3 configured as described above in the case 4 will be described with reference to FIGS. FIG. 6 is a perspective view of the case 4, and FIG. 7 is a development view in which the ring light guide 3 accommodated in the case 4 is developed in a planar shape.

  The case 4 is provided with a speedometer space 4A, a tachometer space 4B, and a fuel gauge space 4C. Here, the speedometer space 4A in which the ring light guide 3 is disposed will be described.

  A cylindrical outer cylindrical wall 41 is formed substantially at the center of the case 4, and a space inside the outer cylindrical wall 41 is a speedometer space 4 </ b> A. The speedometer space 4A is provided with a cylindrical inner cylindrical wall 42 substantially parallel to the outer cylindrical wall 41, and an annular arrangement is provided between the outer cylindrical wall 41 and the inner cylindrical wall 42. A groove 43 is formed. The arrangement groove 43 has the same shape as the ring light guide 3 in plan view. That is, the arrangement groove 43 is formed in an annular shape having a groove width enough to fit the guide main body portion 31 of the ring light guide 3, and portions corresponding to the three light incident portions 32, 32, 32 of the ring light guide 3. Projecting radially outward so that the light incident portions 32, 32, 32 fit. The ring light guide 3 is disposed in the disposition groove 43. In the space inside the inner cylindrical wall 42, a light guide for illuminating the scale 13a and the number 13b of the dial 13 and a light guide for illuminating the pointer 14 are disposed.

  Furthermore, a total of three bottom walls 44 are formed in the arrangement groove 43 along the back surface 33 b of each light guide portion 33 of the ring light guide 3. Specifically, each bottom wall 44 extends substantially parallel to the back surface 32b of the light incident portion 32, and further extends substantially parallel to the back surface 33b from the base end portion to the distal end portion of the back surface 33b of the light guide portion 33. ing. That is, a portion of the bottom wall 44 corresponding to the distal end portion of the light guide portion 33 (hereinafter referred to as a distal end portion) corresponds to the proximal end portion of the light guide portion 33 and the light incident portion 32 of the bottom wall 44. It floats on the surface 33a side of the light guide 33 in the central axis X direction from the portion (hereinafter referred to as the base end portion). As a result, in the two adjacent bottom walls 44, 44, the base end portion of one bottom wall 44 and the tip end portion of the other bottom wall 44 are shifted in the central axis X direction, and between them, Is formed with a gap in the central axis X direction.

  When the ring light guide 3 is disposed in the disposition groove 43, the back surface 32 b of the light incident portion 32 and the back surface 33 b of the light guide portion 33 abut against the bottom wall 44. At this time, the distal end surface 32 c of the light incident portion 32 is between the proximal end portion of the bottom wall 44 with which the light incident portion 32 abuts and the distal end portion of another bottom wall 44 adjacent to the bottom wall 44. It faces the gap.

  Here, the printed board 12 is disposed on the back side (that is, the back side) of the case 4. Specifically, the base end portion of the bottom wall 44 of the case 4 is in contact with the printed board 12. On the other hand, a space is formed between the front end portion of the bottom wall 44 and the printed board 12, and the light source 12 a provided on the printed board 12 is located in the space behind the front end portion of the bottom wall 44. .

  That is, of the two adjacent bottom walls 44, 44, the front end surface 32 c of the light incident portion 32 and the light source 12 a are interposed via a gap between the base end portion of one bottom wall 44 and the front end portion of the other bottom wall 44. Are facing each other. And the light source 12a is comprised so that light may be irradiated toward the front end surface 32c of the light-incidence part 32. FIG.

  The light from the light source 12a enters the light incident part 32 from the front end surface 32c. That is, the tip surface 32c is an incident surface. The light incident on the light incident part 32 passes through the light incident part 32 and enters the proximal end part of the light guide part 33. The light incident on the proximal end portion of the light guide portion 33 travels in the light guide portion 33 toward the distal end portion. Here, since the back surface 33b of the light guide portion 33 is inclined so as to approach the front surface portion 33a from the base end portion toward the tip end portion, the light traveling in the light guide portion 33 toward the tip end portion is Eventually, the light enters the back surface 33b and is reflected by the back surface 33b. The light reflected by the back surface 33b is emitted from the front surface 33a to the outside of the light guide 33. That is, the light incident from the distal end surface 32c of the light incident portion 32 is reflected from the rear surface 33b and emitted from the front surface 33a while proceeding from the proximal end portion toward the distal end portion through the light guide portion 33.

  On the surface side of the ring light guide 3, as shown in FIG. Specifically, a ring-shaped slit 13d of the dial 13 is located at a portion facing the surface 33a of the ring light guide 3. That is, the light emitted from the surface 33a of the ring light guide 3 is transmitted to the surface side of the dial 13 through the ring-shaped slit 13d. As a result, the dial 13 emits light at the outer peripheral edge portion of the speedometer according to the shape of the ring-shaped slit 13d. Thus, the visibility of the speedometer is improved and the aesthetics are improved.

  Here, since the light incident part 32 of the ring light guide 3 is deviated outward from the guide main body part 31 and the light source 12a is provided so as to face the tip end face 32c, it faces the central axis X direction. The light source 12a does not overlap the guide body 31. Thereby, the light of the light source 12a is not directly irradiated to the ring-shaped slit 13d. In addition, since the light from the light source 12a is introduced into the light guide unit 33 through the light incident unit 32, it is possible to prevent the strong light from the light source 12a from being incident on the light guide unit 33 immediately. Color unevenness of the light portion 33 can be suppressed.

  Therefore, according to the present embodiment, the back surface 33b of the light guide portion 33 of the ring light guide 3 is inclined so that the thickness of the light guide portion 33 becomes thinner from the proximal end side toward the distal end side in the circumferential direction, The ring light guide 3 can be formed compactly by providing the light incident part 32 so as to extend from the base end part of the light guide part 33 through the space S on the back side of the front end part of the adjacent light guide part 33. . That is, by providing the light incident part 32 using the space S on the back side of the front end part of the light guide part 33 formed by inclining the back surface 33b of the light guide part 33, The amount of protrusion from the guide body 31 in the thickness direction and the radial direction can be suppressed. That is, compared to the configuration in which the light incident portion having the same length as that of the present embodiment is extended outwardly from the outer peripheral surface of the guide main body portion 31, in this embodiment, a part of the light incident portion 32 is the center. When viewed in the direction of the axis X, since it overlaps with the tip portion of the adjacent light guide portion 33, the protrusion amount of the light incident portion 32 to the outside of the guide main body portion 31 can be suppressed accordingly. At this time, since the light incident part 32 is provided by using the space S on the back side of the tip part of the light guide part 33 formed by inclining the back surface 33b of the light guide part 33, the protrusion in the thickness direction is provided. The amount can also be reduced. As a result, the ring light guide 3 can be formed compactly.

  Specifically, in the configuration in which the ring light guide 3 illuminates the ring light guide 3 as in the present embodiment, when the light source 12a is arranged on the back side of the guide main body 31 of the ring light guide 3, only the light source 12a portion becomes bright. Therefore, the light source 12 a is not disposed on the back side of the guide main body portion 31, but is disposed at a position shifted from the guide main body portion 31. That is, when the ring light guide 3 is viewed from the surface 33a side, the light source 12a is provided at a position that does not overlap with the guide main body 31, and the light incident portion 32 extending toward the light source 12a so as to deviate from the guide main body 31 is provided. By providing the light, the light from the light source 12 a is guided to the guide main body 31 via the light incident part 32. By doing so, color unevenness due to the presence of the light source 12a can be suppressed, and illumination can be performed in an annular shape or an arc shape via the ring light guide 3.

  Further, when the light from the light source 12 a is introduced into the guide main body 31 through the light incident part 32, it is preferable to secure a certain length of the light incident part 32. That is, in the light incident part 32, the light incident from the light source 12a is hardly attenuated, and the light incident part 32 is a relatively bright part. In particular, in the light incident portion 32, the tip surface 32c on which light from the light source 12a is incident and the vicinity of the tip surface 32c (these are collectively referred to as the tip portion) are bright. If the length of the light incident portion 32 is short and the distance from the distal end surface 32 c of the light incident portion 32 to the light guide portion 33 is short, strong light from the light source 12 a is immediately introduced into the light guide portion 33. As a result, color unevenness occurs in the light guide 33. Therefore, by securing a certain length of the light incident portion 32, light that is moderately attenuated and diffused is introduced into the light guide portion 33, and color unevenness in the light guide portion 33 is suppressed.

  As described above, the light source 12a is provided at a position not overlapping the guide main body 31, the light incident portion 32 extending toward the light source 12a so as to be deviated from the guide main body 31 is provided, and strong light from the light source 12a is guided by the light. If the light incident part 32 is configured to have a certain length so as not to enter the main body part 31, the light incident part 32 has to protrude from the guide main body part 31 to some extent.

  Therefore, the back surface 33b of the light guide part 33 of the ring light guide 3 is inclined so that the thickness of the light guide part 33 becomes thinner from the base end side toward the front end side in the circumferential direction, and the light incident part 32 is guided. By providing the base part of the part 33 so as to extend through the space S on the back side of the tip part of the adjacent light guide part 33, the light incident parts 32, 32, 32 can be formed in a compact manner. The ring light guide 3 can be formed compactly.

  Here, the space in which the speedometer and the like can be arranged in the vehicle display device 1 is limited as shown in FIGS. In order to dispose the ring light guide 3 including the light incident portions 32, 32, 32 in a limited space, the guide main body portion 31 must be made smaller, or the light incident portions 32, 32, 32 are in other locations. The ring light guide 3 must be arranged so as not to interfere with the member, and is subject to various design restrictions. That is, the greater the amount of protrusion of the light incident portions 32, 32, 32 from the guide main body portion 31, the lower the design freedom of the ring light guide 3 and the vehicle display device 1.

  On the other hand, as described above, by forming the ring light guide 3 in a compact manner, the guide main body portion 31 that directly contributes to illumination can be made as large as possible in a limited space, and the incident light can enter. The degree of freedom in designing the ring light guide 3 and the vehicle display device 1 can be improved, for example, the ring light guide 3 can be arranged without much concern about interference between the parts 32, 32, 32 and other members.

  In the dial 13, it is necessary to shield the light source 12a so that light from the light source 12a does not leak. In the present embodiment, as shown in FIG. 2, the dial 13 has a scale on the back side of the dial 13 so that the light from the light source 12a does not leak directly to the front side of the dial 13, as shown in FIG. 13a, the number 13b, etc. are not provided, and the black paint is still applied. Further, the portion of the dial 13 where the light source 12a is located on the back side is covered with the wind plate 16, and is hardly exposed on the front side (that is, the user side). In this way, light from the light source 12a is prevented from leaking directly to the surface side of the dial 13. The light incident portions 32, 32, and 32 are portions for guiding the light from the light source 12a to the guide main body portion 31, unlike the guide main body portion 31 formed in a predetermined shape so as to perform desired illumination. It is not a part that directly contributes to lighting. Therefore, of the light incident portions 32, 32, 32, the portion protruding from the guide main body portion 31 when viewed from the surface side (toward the central axis X direction) is shielded similarly to the light source 12 a. In other words, the light incident portions 32, 32, 32 are also covered with the black painted portion of the dial 13. That is, the portion of the dial 13 that covers the light sources 12a, 12a, 12a and the light incident portions 32, 32, 32 (specifically, the portion of the light incident portions 32, 32, 32 that protrudes from the guide main body 31) The scale 13a and the number 13b cannot be arranged. Thus, the arrangement of information on the dial 13 is also restricted by the light source 12a and the light incident parts 32, 32, 32.

  On the other hand, by forming the ring light guide 3 compactly as described above, when the ring light guide 3 is viewed in the direction of the central axis X, the light incident portions 32, 32, 32 are separated from the guide main body portion 31. The amount of protrusion can be suppressed. By doing so, it is possible to reduce the area of the dial 13 where the scales 13a and the numbers 13b cannot be arranged. As a result, in the vehicle display device 1, more information can be displayed more easily by effectively using a limited space.

  Further, when the light incident part 32 is viewed with a part of the distal end surface 32c facing the central axis X direction, another light guide adjacent to the light guide part 33 to which the light incident part 32 is connected. Even if the light incident portions 32, 32, 32 are provided so as to deviate outward from the guide main body portion 31 by being configured to overlap the tip portion of the portion 33, the amount of protrusion of the light incident portion 32 can be further increased. In this way, the ring light guide 3 can be formed more compactly.

  In addition, when the front end portion of the light incident portion 32 that is brighter than the guide main body portion 31 is viewed in the direction of the central axis X, the front end portion of the adjacent light guide portion 33 overlaps. Even if it exists, the light of the front-end | tip part of the light-incidence part 32 does not have a bad influence on the front-end | tip part of the light guide part 33. That is, since there is a gap (that is, an air layer) in the direction of the central axis X between the distal end portion of the light incident portion 32 and the distal end portion of the light guide portion 33, light from the distal end portion of the light incident portion 32 is present. Is reflected on the front surface 32a of the light incident part 32, attenuated while propagating through the air layer, reflected on the back surface 33b of the front end part of the light guide part 33, etc. before being transmitted to the front end part of the light guide part 33. It ’s getting weaker. Therefore, color unevenness does not occur at the tip of the light guide 33.

  Furthermore, when viewed in the direction of the central axis X, the tip end surface 32c of the light incident portion 32 overlaps the guide main body portion 31, but the portion of the guide main body portion 31 corresponding to the ring-shaped slit 13d. And (that is, the ring-shaped slit 13d of the dial 13) do not overlap. Thereby, when the light from the light source 12a enters the light incident part 32, the light reflected by the front end surface 32c of the light incident part 32 can be made difficult to leak into the ring-shaped slit 13d.

  Furthermore, by providing a partition wall 44 that separates the tip of the light guide 33 and the light source 12a in the direction of the central axis X between the tip of the light guide 33 and the light source 12a, the light of the light source 12a is transmitted. Leakage to the tip of the light guide 33 can be suppressed. That is, in this embodiment, the light source 12a and the guide main body 31 of the ring light guide 3 do not overlap when viewed toward the central axis X (that is, they are displaced in the radial direction). However, by providing the partition wall 44, light leakage to the distal end portion of the light guide portion 33 can be further suppressed.

  However, in two adjacent partitions 44, 44, a gap is formed between the base end of one partition 44 and the tip of the other partition 44, so that part of the light from the light source 12a is , Due to diffraction, it can leak to the tip of the light guide 33. Here, in the light guide portion 33, the amount of light incident from the proximal end portion is reduced at the distal end portion, and therefore the distal end portion tends to be darker than the proximal end portion. For this reason, the back surface 33b of the distal end portion of the light guide portion 33 is subjected to a texture process to compensate for the insufficient light amount at the distal end portion. That is, it is not preferable that the light guide unit 33 is directly irradiated by the light source 12a. However, if there is a slight amount of light leakage such as diffracted light from the light source 12a, the shortage of light at the tip of the light guide unit 33 is compensated. The color unevenness of the light guide 33 can be suppressed.

<< Other Embodiments >>
The present invention may be configured as follows with respect to the embodiment.

  That is, although the embodiment using the ring-shaped ring light guide 3 as the light guide has been described, the present invention is not limited to this. For example, the ring light guide 3 does not need to be circular as long as it is annular, and may be elliptical or polygonal such as a quadrangle. The light guide is not limited to an annular shape, and may be an arc shape such as a U-shape or a horseshoe shape. That is, the light guide is not limited to a closed shape like an annular shape, but may be any shape as long as the member of the line is curved or bent.

  Further, in the ring light guide 3, the guide body 31 is composed of a plurality of light guides 33, 33,..., But is not limited to this. For example, as shown in FIG. 8, the guide main body 231 of the ring light guide 203 may be configured by a single light guide 233. Specifically, the guide main body 231 is formed in an annular shape around the central axis X. The guide main body 231 has a back surface 233b inclined with respect to the front surface 233a so that the thickness gradually decreases from a predetermined base end toward one of the circumferential directions (the clockwise direction in FIG. 8). ing. That is, the guide main body 231 gradually decreases in thickness from the proximal end toward one side in the circumferential direction, and is thinnest at the distal end that is the portion returned to the proximal end. As described above, the back surface 233b of the light guide unit 233 is inclined, so that the back surface 233b of the distal end portion of the light guide unit 233 is lifted to the front surface 233a side compared to the back surface 233b of the base end portion of the light guide unit 233. Yes. Thereby, a space S is formed on the back side of the front end portion of the light guide portion 233. A light incident portion 232 is connected to the proximal end portion of the light guide portion 233. Specifically, the light incident portion 232 extends in the tangential direction of the guide main body portion 231 from the proximal end portion of the light guide portion 233 through the space S on the back side of the distal end portion. A part of the front end surface 232 c of the light incident portion 232 is located in the space S. That is, when viewed in the direction of the central axis X, most of the distal end surface 232c of the light incident portion 232 protrudes radially outward from the guide main body portion 231, but a part of the distal end surface 232c is It overlaps with the guide main body 231 (specifically, the front end of the light guide 233). Other configurations of the light incident portion 232 are the same as those of the light incident portion 32.

  In the ring light guide 203 configured as described above, light from the light source enters the light incident portion 232 from the front end surface 232 c, and the light incident on the light incident portion 232 passes through the light incident portion 232 and enters the light guide portion 233. Incident to the base end. The light incident on the light guide portion 233 travels from the base end portion toward the tip end portion, is reflected by the back surface 233b, and is emitted from the front surface 233a.

  By doing so, the back surface 233b of the light guide 233 of the ring light guide 203 is inclined so that the thickness of the light guide 233 becomes thinner from the proximal end side toward the distal end side in the circumferential direction, and the light incident portion 232 is formed. Is provided so as to extend from the proximal end portion of the light guide portion 233 through the space S on the back side of the distal end portion of the light guide portion 233, so that the light incident portion 232 is provided so as to deviate outward from the guide main body portion 231. Even if it is a structure, the ring light guide 203 can be formed compactly.

  In the above-described embodiment, when at least a part of the distal end surface 32c of the light incident portion 32 is viewed in the direction of the central axis X, the portion corresponding to the ring-shaped slit 13d in the guide main body portion 31 overlaps. Although it overlaps with the guide main body 31 to such an extent that it does not become, it is not limited to this. That is, the front end surface 32c of the light incident portion 32 may be configured so as not to overlap the guide main body portion 31 when viewed in the direction of the central axis X, and to protrude completely from the guide main body portion 31. The structure which overlaps with the part corresponding to the ring-shaped slit 13d among 31 may be sufficient. The former is preferable from the viewpoint of suppressing color unevenness of the ring light guide 3, and the latter is preferable from the viewpoint of making the ring light guide 3 compact.

  Furthermore, in the said embodiment, although the light-incidence part 32 is linearly extended from the base end part of the light guide part 33 to the tangential direction in this base end part, it is not restricted to this. That is, the light incident portion 32 may extend in a direction other than the tangential direction at the proximal end portion of the light guide portion 33, and the light incident portion 32 is not linear but extends in a bent or curved shape. There may be. However, in order to introduce light smoothly from the light incident part 32 to the light guide part 33 without being attenuated, it is preferable to provide the light incident part 32 so as to extend in a tangential direction of the light guide part 33 or a direction close thereto. .

  Moreover, in the said embodiment, although the ring light guide 3 is used in order to irradiate a speedometer, it is not restricted to this. For example, the ring light guide 3 may be used to illuminate a tachometer or a fuel gauge, or may be used to illuminate other parts of the vehicle display device 1.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for a light guide used for illumination of a vehicle instrument and a vehicle display device including the light guide.

DESCRIPTION OF SYMBOLS 1 Display apparatus for vehicles 3 Ring light guide (light guide)
31 Guide body (main body)
32 Light entrance part 32c Front end surface 33 Light guide part 33a Front surface 33b Back surface 203 Ring light guide (light guide)
231 Guide body (main body)
232 Light incident part 232c Front end surface 233a Front surface 233b Back surface X Central axis (axis)
S space

Claims (4)

A light guide used for lighting a vehicle instrument,
A body portion formed in an annular shape or an arc shape around a predetermined axis;
The main body is divided into a plurality of light guides in the circumferential direction,
Each light guide has a front surface and a back surface facing each other in the axial direction, and the back surface is inclined so that the thickness in the axial direction becomes thinner toward one of the circumferential directions, and the thickness is increased. It is configured to reflect the light incident from the base end side to the thin distal end side while reflecting it on the back surface and to emit from the front surface,
On the back side of the tip of each light guide part, a space is formed by tilting the back side of the light guide part,
From the base end part of each light guide part, the light incident part for guiding the light from the light source to the light guide part is another light guide part adjacent to the other side in the circumferential direction with respect to the light guide part. A light guide that extends through the space on the back side. A light guide used for lighting a vehicle instrument,
A main body formed in an annular shape around a predetermined axis;
The main body portion has a front surface and a back surface facing each other in the axial direction, and the axial thickness gradually decreases from a predetermined base end portion toward one side in the circumferential direction, and returns to the base end portion. The back surface is inclined so as to be the thinnest at the portion, and is configured to reflect the light incident from the base end portion in the circumferential direction and reflect the light from the back surface to be emitted from the front surface.
On the back side of the tip, a space is formed by tilting the back surface,
A light guide body, wherein a light incident portion for guiding light from a light source to the main body portion extends from the base end portion through the space on the back side of the distal end portion. The light guide according to claim 1 or 2,
The front end surface of the light incident portion is an incident surface on which light from a light source is incident, and at least a part of the light incident portion overlaps the main body portion when viewed in the axial direction in the space. A light guide characterized by that. A light source;
A light guide that guides light from the light source to a predetermined illumination target part; and
A vehicle display device comprising a case for housing the light source and the light guide;
The light guide is the light guide according to any one of claims 1 to 3,
The light source is provided at a position facing the front end surface of the light incident part for each light guide part,
The vehicle display device, wherein the case is provided with a partition wall that blocks light from the light source at a position between the light source and the main body.

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