JP3362385B2 - Light guide unit and vehicle display device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light guide unit and a vehicle display device, and more particularly to a light guide unit and a vehicle display device used in a black face type vehicle combination meter.

[0002]

2. Description of the Related Art FIG. 9 shows an exploded perspective view of a conventional vehicle combination meter. The vehicle combination meter 100 is roughly classified into a casing 102 provided with a night illumination light source (bulb light bulb) 101 for performing illumination at night, an instrument group 103 for displaying a running state of a vehicle, and an instrument. In order to perform the ring illumination of the movement assemblies 110 to 113 that form the group 103, the instrument group 103 is illuminated by the illumination light emitted from the light source 101 for night illumination and reflected by the look-back unit 105, which will be described later. Ring light guide plate 1 for performing
04, the look-back unit 105 for shielding a portion other than the display portion of the instrument group 103 and the like from the user, and protects the instrument group 103 and prevents dust and the like from entering the vehicle combination meter 100. And a front glass unit 106 for.

The instrument group 103 includes a speedometer unit for displaying the speed of the vehicle, a tachometer unit for displaying the number of revolutions of the engine, a fuel gauge unit for displaying the remaining amount of fuel, and an engine cooling. A temperature gauge unit for displaying the temperature of water and a temperature gauge unit, and a speedometer unit, a tachometer unit, a fuel gauge unit, and a temperature gauge unit are integrated with a pointer, a cross coil type movement, and a dial plate described later. And constitute movement assemblies 110 to 113, respectively.

Here, the movement assembly 110-1
Since the configuration of 13 is the same, the movement assembly 110 including the speedometer unit will be described as an example. FIG. 10 shows a partial cross-sectional view in the assembled state near the movement assembly 110 including the speedometer unit.

The movement assembly 110 including the speedometer unit is supplied with a current according to the speed of the vehicle and has a cross coil type movement 120 having a cross coil for driving a pointer 123 attached to a rotary shaft 120A, and a night time. A light guide plate 12 for a dial for guiding the illumination light LL ′ emitted from the illumination light source 101 to the dial.
1 and a light guide plate 121 for a dial plate, which is integrally formed with a dial plate 122 in which characters are printed or cut out in advance.

Next, the general operation will be described. The movement assembly 110 including a speedometer unit displays the speed of the vehicle based on the output signal of a vehicle speed sensor (not shown). The movement assembly 111 including the tachometer unit displays the rotation speed of the engine based on the output signal of a rotation speed sensor (not shown). The movement assembly 112 including the fuel gauge unit displays the remaining amount of fuel based on the output signal of a fuel sensor (not shown). The movement assembly 113 including the temperature gauge unit displays the temperature of the cooling water of the engine based on the output signal of a temperature sensor (not shown).

In parallel with these, the light source 101 for night illumination
10, the illumination light LL ′ emitted from the night illumination light source 101 is incident on the dial plate light guide plate 121 that constitutes the movement assemblies 110 to 113, and the dial plate LL 'is formed. The character shines through the character print portion 122 or the character cutout portion.

Further, the illumination light LL ′ emitted from the night illumination light source 101 is reflected by the dial unit 105, enters the ring illumination light guide plate 104, and is emitted in a ring shape to form a ring shape around the dial 122. To illuminate. More specifically, in the cross coil type movement 120 corresponding to the speedometer unit, a current according to the speed of the vehicle is passed through the cross coil, and the pointer 123 attached to the rotating shaft 120A is driven to display the speed. Will be done.

In parallel with this, when the power source of the night illumination light source 101 is supplied, the illumination light LL 'emitted from the night illumination light source 101 enters the dial light guide plate 121 and enters the dial 122. Is led to, and the character display portion becomes bright. Further, the illumination light LL ′ emitted from the night illumination light source 101 is reflected by the dial unit 105, enters the ring illumination light guide plate 104, and is emitted in a ring shape to move the assembly 1 including the speedometer unit.
The periphery of the dial plate 122 of 10 is illuminated in a ring shape.

[0010]

In the above-mentioned conventional vehicle combination meter, when the ring illumination is performed, since the reflected light of the return is used, there is a problem that the brightness is low and unevenness occurs.

Further, since the light source for night illumination is used as the light source for ring illumination, there is a problem that ring illumination cannot be performed in the daytime. Further, since it also serves as a light source for night illumination, there is a problem in that it is not possible to make the color different from the light for illuminating the dial, and there is no room for selecting a color variation.

Furthermore, there is a problem that the inside of the movement assembly on the back side of the dial unit is visible to the user through the ring illumination light guide plate. In addition to these technical problems, there is a problem in that the texture of the ring illumination is low in terms of design.

Therefore, a first object of the present invention is to provide a light guide unit and a vehicular display device which have a high brightness and can perform uniform illumination, and can also perform ring illumination for daytime illumination. A second object of the present invention is to provide a light guide unit and a vehicle display device capable of expanding the selection range of color variations of ring illumination.

A third object of the present invention is to provide a light guide unit and a vehicular display device in which the inside of the movement assembly cannot be seen by the user.

[0015]

[0016]

[0017]

[0018]

The invention according to claim 1 is
A light guide unit provided in a vehicle display device for ring-illuminating the periphery of a display unit of an indicating instrument, and having an incident surface on which illumination light is incident from an external light source,
The light guide member main body has an arcuate shape in a plan view, and the light guide member main body is assumed to be virtual incident light incident from a predetermined reference light emission direction, and the incident angle of the virtual incident light is a predetermined angle equal to or greater than a critical angle. And a light guide reflecting surface formed so that the incident angle of the virtual incident light is smaller than the critical angle.

According to the first aspect of the invention, the emitting reflection surface of the light guide member main body is assumed to be virtual incident light incident from a predetermined reference light emitting direction, and the incident angle of the virtual incident light is a critical angle. Since the light guide reflection surface is formed so as to form the above predetermined angle and the incident angle of the virtual incident light is smaller than the critical angle, the external light having the same optical path as the virtual incident light is formed. Is almost transmitted through the light guide reflection surface,
It is possible to reduce the possibility that the inside of the vehicular display device is visually recognized from the user side, and the illumination light is reflected by the emission reflection surface while being reflected by the light guide reflection surface, thereby forming an arc-shaped ring. It is emitted as illumination light.

[0020] According to a second aspect of the invention, a light guide unit according to claim 1, wherein the dial unit constituting the assembly combined with the light guide unit, with composing the assembly, corresponding to the light guide unit A plurality of the light sources provided as described above, the indicating instrument that has a pointer and performs various displays, and a dial unit that constitutes the display unit.

According to the second aspect of the invention, the dial unit and the plurality of light sources are combined with the light guide unit of the first aspect to form an assembly. The illumination light emitted from each light source is incident on the light guide unit and emitted as arc-shaped ring illumination light to ring-illuminate the display unit including the pointer of the indicating instrument and the dial unit.

According to a third aspect of the invention, in the second aspect of the invention, the light source is a full-color LED. According to the invention described in claim 3 , in addition to the effect of the invention described in claim 2 , since the light source is a full-color LED, ring illumination of any color can be performed.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described with reference to the drawings. First Embodiment FIG. 1 shows an exploded perspective view of a vehicle combination meter of the first embodiment.

The combination meter 1 for a vehicle is roughly classified into a casing 3 provided with a light source 2 for illuminating a dial.
A group of instruments 4 for displaying the running state of the vehicle, a light guide plate 5 for guiding the dial illumination light CL from the dial illumination light source 2 to a dial to be described later, and various character displays. A dial 7 for performing the movement, and a pointer 7 that is integrated with the movement 4A and configures the instrument group 4, and a side for performing ring illumination of a predetermined area (display portion) on the dial 6 corresponding to each movement 4A. Light L for ring illumination emitted from the full-color LED 8 which is a light source for ring illumination by the edge light method
Ring illumination light guide plates 9A and 9B having a ring shape for guiding L (see FIG. 5), and a look-back unit 10 for shielding a portion other than the display portion of the instrument group 4 and the like from the user.
And a front glass unit 11 for protecting the instrument group 4 and for preventing dust and the like from entering the vehicle combination meter 1. In this case, the ring illumination light guide plates 9A and 9B function as a light guide unit.

Each movement 4A constituting the instrument group 4
Are a speedometer for displaying the speed of the vehicle, a tachometer for displaying the number of revolutions of the engine, a fuel gauge for displaying the remaining amount of fuel, and a temperature gauge unit for displaying the temperature of the cooling water of the engine. Constitute.

Here, the full-color LED 8 is red L
LE that can house ED, green LED and blue LED in one package and drive each LED independently
It is a D unit. Further, the full-color LED 8, the ring illumination light guide plates 9A and 9B, and the dial unit 10 are integrally combined to form an assembly. As a result, it is not necessary or easy to arrange the connection of the rear surface of the casing 3 with a wiring board (not shown), and the assembling work can be facilitated and simplified.

FIG. 2 shows (a) a plan view, (b) a front view, and (c) a side view of the ring illumination light guide plate 9A. As shown in FIG. 2A, the ring illumination light guide plate 9A has a light guide path 15 that is arcuate in a plan view, and is a full-color LED.
Incident surface 16 on which the ring illumination light LL from 8 is incident
And a light emitting reflection surface 17 (see FIG. 2B) for emitting the ring illuminating light LL incident from the incident surface 16, and the ring illuminating light LL incident from the incident surface 16 is reflected and propagated. And a reflection surface 18 for light propagation.

As the material of the ring light guide plate 9A,
A transparent acrylic resin is used, and the reflecting surface 17 for injection has a
In order to improve the reflectance, white paint or light reflection treatment such as hot stamping is applied. FIG. 3 shows (a) a plan view, (b) a front view and (c) a side view of the ring illumination light guide plate 9B.

As shown in FIG. 3A, the ring illumination light guide plate 9B has a light guide path 20 having an arc shape in plan view, and the ring illumination light LL from the full-color LED 8 is incident on the light guide plate 9B. The surface 21 and the light emitting reflection surface 22 that emits the ring illumination light LL incident from the incident surface 21 (see FIG. 3).
(See (b)) and a light propagation reflection surface 23 that reflects and propagates the ring illumination light LL incident from the incidence surface 21.

As a material for the ring illumination light guide plate 9B,
A transparent acrylic resin is used, and the emitting reflection surface 22 is
In order to improve the reflectance, white paint or light reflection treatment such as hot stamping is applied. FIG. 4 shows a partially enlarged front view of the vehicle combination meter 1 in the state where the ring illumination light guide plates 9A and 9B are mounted on the dial plate 6 during assembly.

The ring illuminating light guide plate 9A is fixed on the dial plate 6 to illuminate the ring around the display portion 6A for the tachometer formed on the dial plate 6. The light guide plate 6B for ring illumination is fixed on the dial plate 6 so as to perform ring illumination around the display portion 6B for the temperature gauge formed on the dial plate 6.

Next, referring to FIG. 5, the light guide plate 9 for ring illumination is used.
The operations of A and 9B will be described. In this case, since the ring illumination light guide plate 9A and the ring illumination light guide plate 9B have the same operation principle, only the operation of the ring illumination light guide plate 9A will be described. The red light, the green light, and the blue light emitted from each of the red LED, the green LED, and the blue LED included in the full-color LED 8 are mixed and emitted from the full-color LED 8 as the ring illumination light LL.

The ring illumination light LL emitted from the full-color LED is reflected directly or by the reflector 8A (see FIG. 5) from the incident surface 16 of the ring illumination light guide plate 9A into the light guide path 15 (see FIG. 2). Incident on the inside. Then, the light is reflected by the light propagating reflection surface 18 to form the light guide path 1.
While propagating in the inside 5, part of it is reflected by the reflecting surface 1 for emission.
By the light reflection processing of No. 7, it is reflected with high efficiency and is emitted to the user side (front glass unit 11 side).

As a result, if ring illumination is performed in the state shown in FIG. 4, the area AR9A emits light by the light guide plate 6A for ring illumination and the area AR9B by light guide plate 6B for ring illumination as shown in FIG. Will emit light. In this case, as shown in FIG.
Is attached with a reflector 8A, which prevents the ring illumination light from leaking in an unnecessary direction.
Ring light with high brightness can be achieved by effectively utilizing the light quantity.

As described above, according to the first embodiment, the light source for ring illumination is provided separately from the light source for dial dial illumination, the light propagation distance is set to be short, and
Since it is configured using high brightness full color LED,
It is possible to perform ring illumination with high brightness and evenness. As a result, it becomes possible to apply the ring illumination to a combination meter for a black face type vehicle.

Since high-intensity ring illumination can be performed,
The user can recognize the ring illumination even in the daytime. Also, a red LED that constitutes a full-color LED,
Ring illumination of an arbitrary color can be performed by individually controlling the turning on / off of the green LED and the blue LED and controlling the light amount.

Further, for example, in a speedometer, the color of the ring illumination is green when traveling at a speed of less than 100 [km / h] and the color of the ring illumination is traveling at a speed of 100 [km / h] or more. For example, the color of the ring light may be red, or the temperature of the temperature gauge may be blue when the temperature gauge is within the proper temperature range, and the color of the ring light may be red outside the proper temperature range. It can also be used.

In the above description, the full-color LED is used as the light source for ring illumination, but it is also possible to use a normal bulb bulb. In this case, it is also possible to arbitrarily set the emission color by using a filter. Second Embodiment The second embodiment is an embodiment in which the shape of the ring illumination light guide plate is formed so that the user cannot look inside the vehicle display device through the ring illumination light guide plate. .

FIG. 7 shows a sectional view of the ring illumination light guide plate of the second embodiment. The light guide plate 80 for ring illumination has a quadrangular cross section, and has an arc shape in plan view.
Further, the ring illumination light guide plate 80 has an incident surface (not shown) on which the illumination light LL is incident from an external light source (not shown) such as a full-color LED, and a light guide path 81 as a light guide member main body having an arc shape in plan view. The light guide path 81 includes
Assuming that virtual incident light LV is incident from a predetermined reference light emission direction (upward direction in FIG. 7), the incident angle θ1 of the virtual incident light LV is formed so as to form a predetermined angle equal to or greater than the critical angle θlim. The reflection surface 82 for emission and the reflection surface 83 for light guide formed so that the incident angle θ2 of the virtual incident light LV is smaller than the critical angle θlim are configured.

As a result, when the user visually recognizes the ring illumination light guide plate 80 from the reference emission direction, the incident angle θ2 is
Since the angle is less than the critical angle θlim, total reflection does not occur, and the direction D1 side that has passed through the light guide reflection surface 83 is visually recognized, and the direction D2 side is less likely to be visually recognized through the light guide reflection surface 83. .

For this reason, it is less likely that the internal structure of the vehicular display device is visible (intermediate appearance). Here, the reason for determining the shape (dimension) of the ring illumination light guide plate 80 will be specifically described with reference to FIG. 8.

In this case, the ideal size of the light guide plate 80 for ring illumination is, as shown in FIG. 8A, the width of the ring illumination is 1.5 [mm], and the full-color LE which is the light source.
The diameter of D is 5 [mmφ], and the thickness of the ring light guide plate 80 on the outer peripheral end side is 6 [mm].

(1) As shown in FIG. 8B, the width of the ring illumination is 1.5 [mm], and the light guide plate 8 for the ring illumination is used.
If the user is prevented from looking through the inside of the vehicular display device through 5, it is conceivable that the thickness of the ring illumination light guide plate 85 is set to about 1.5 mm or more.

However, in this case, the light guide plate 8 for ring illumination is used.
Since the thickness of 5 is thinner than the diameter of the full color LED, the emitted light of the full color LED cannot be effectively used,
There is a problem that it gets dark. (2) As shown in FIG. 8C, when the thickness of the ring illumination light guide plate 86 is set so that the emitted light of the full-color LED can be effectively used, the thickness becomes 6 [mm].

As a result, the width of the ring illumination becomes a little over 6 [mm], which causes a problem that it becomes too thick. (3) Therefore, as shown in FIG. 8D, a part of the reflecting surface 87 for emission is subjected to light reflection processing (white coating or hot stamping processing) to make the width of the ring illumination 1.5.
If it is [mm], there is a problem that the user can look into the inside of the vehicular display device through the ring illumination light guide plate 88 due to the total reflection of the region B not subjected to the light reflection processing.

(4) Then, by removing the shaded portion shown in FIG. 8E from the ring illumination light guide plate 88 shown in FIG. 8D, the problems occurred in the above (1) to (3). The points can be removed, and the ideal ring illumination light guide plate 80 shown in FIG. 8A can be obtained.

[0047]

[0048]

[0049]

According to the first aspect of the present invention, the emitting reflection surface of the light guide member main body is assumed to be virtual incident light incident from a predetermined reference light emitting direction, and the incident angle of the virtual incident light is Since the light guide reflection surface is formed so as to form a predetermined angle equal to or greater than the critical angle, and the incident angle of the virtual incident light is smaller than the critical angle, it has the same optical path as the virtual incident light. External light is almost transmitted through the light guide reflection surface, which can reduce the possibility that the inside of the vehicular display device is visually recognized from the user side, and the illumination light is reflected by the light guide reflection surface. At the same time, the light is reflected by the emitting reflection surface and emitted as arc-shaped ring illumination light, so that high-intensity ring illumination can be performed.

According to the invention described in claim 2 , the return unit and the plurality of light sources are combined with the light guide unit according to claim 1 to form an assembly, and the illumination light emitted from each light source is guided. It enters the unit and is emitted as arc-shaped light for ring illumination to ring-illuminate the display unit including the pointer and dial unit of the indicating instrument, so that the indicating function of the indicating instrument is not impaired, and the brightness is high and uniform. It is possible to configure a vehicular indicating instrument with good visibility and high visibility, which can perform various ring illuminations.

According to the invention of claim 3 , in addition to the effect of the invention of claim 2 , since the light source is a full-color LED, ring illumination of any color can be performed and the visibility can be improved. At the same time, the designability can be improved.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a vehicle combination meter according to a first embodiment.

FIG. 2A is a plan view of a ring illumination light guide plate 9A,
It is a front view and (c) side view.

FIG. 3A is a plan view of a ring illumination light guide plate 9B,
It is a front view and (c) side view.

FIG. 4 is a partially enlarged front view of the combination meter for a vehicle, in which the light guide plates for ring illumination 9A and 9B are mounted on the dial plate during assembly.

FIG. 5 is an operation state explanatory diagram of the first embodiment.

FIG. 6 is an explanatory diagram of a ring illumination state.

FIG. 7 is an explanatory diagram of the second embodiment.

FIG. 8 is a specific explanatory diagram of the reason for determining the shape (dimension) of the ring illumination light guide plate of the second embodiment.

FIG. 9 is an exploded perspective view of a conventional vehicle combination meter.

FIG. 10 is a structural explanatory view of a conventional movement assembly.

[Explanation of symbols]

1 Vehicle combination meter 2 Light source for dial illumination 3 casing 4 instrument group Light guide plate for 5 dials 6 dial 7 guidelines 8 full color LED 9A, 9B Ring light guide plate 10 Return unit 11 Front glass unit 20 full color LED 21 Light guide plate for ring illumination 22 Diffuser film (diffusion film) 80 Light guide plate for ring illumination 81 light guide path 82 Reflection surface for emission 83 Light guide reflection surface Light for CL dial illumination LL, LL1, LL2, LL3 Ring illumination light LV virtual incident light θ1, θ2 incident angle θlim critical angle

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroyuki Yokota 1-7-1 Yokoi Shimada City, Shizuoka Prefecture Yazaki Keiki Co., Ltd. (72) Inventor Hiroshi Yamashita 1-7-1 Yokoi Shimada City Shizuoka Prefecture Yazaki Keiki Co., Ltd. (56) References Japanese Unexamined Patent Publication No. 9-287980 (JP, A) Actually open 4-130025 (JP, U) Actually open 4-136519 (JP, U) Actually public 59-39603 (JP, Y1) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G12B 11/02 G01D 11 / 28,13 / 02,13 / 28

Claims (3)

(57) [Claims] 1. A light guide unit provided in a vehicle display device for ring-illuminating a periphery of a display unit of an indicating instrument, the light guide unit having an incident surface on which illumination light is incident from an external light source.
Both are provided with a light guide member main body having an arc shape in plan view, and the light guide member main body is incident from a predetermined reference light emitting direction.
Assuming virtual incident light, the incident angle of the virtual incident light is critical.
Reflection for emission that is formed to form a predetermined angle that is equal to or greater than the angle
Surface and the incident angle of the virtual incident light is smaller than the critical angle.
Light unit, characterized by comprising a Uni-formed light reflecting surface. 2. The light guide unit according to claim 1, and the light guide unit in combination to form an assembly.
Configures the end unit and the assembly, and
A display device for a vehicle , comprising: a plurality of light sources provided corresponding to each other; the indicator instrument that has a pointer and performs various displays; and a dial unit that constitutes the display unit. 3. The vehicle display device according to claim 2.
And the light source is a full-color LED
Vehicle display device.