EP3167250A1

EP3167250A1 - Illuminated pointer instrument for a motor vehicle

Info

Publication number: EP3167250A1
Application number: EP15735856.5A
Authority: EP
Inventors: Matthias WUNDERLICH; Lutz Diederichs
Original assignee: Audi AG
Current assignee: Audi AG
Priority date: 2014-07-11
Filing date: 2015-07-07
Publication date: 2017-05-17
Also published as: CN106489067B; DE102014010310B3; WO2016005051A1; US9837172B2; CN106489067A; US20170178754A1

Abstract

The invention relates to an indication device (12) for a motor vehicle (10), comprising a pointer needle (18) with a transparent optical waveguide (42) configured, at a light-entry side (64), to receive light (38) propagating along a direction of propagation (68) from a light-coupling device (20, 46) and, at a light-exit side (72), to emit the light (38) in an emission direction (40). The invention is based on the object of providing in the indication device (12) a pointer needle (18) that is clearly perceivable in the dark. To this end, the optical waveguide (42) has a scattering side (74) opposite to the light-exit side (70), which scattering side has a plurality of steps (80) arranged offset to one another across the propagation direction (68).

Description

Illuminated pointer instrument for a motor vehicle

DESCRIPTION: The invention relates to a display device for a motor vehicle. The display device is designed as a pointer instrument and has a pointer with a pointer flag, in which a transparent light guide emits light in a propagation direction towards a viewer. Such pointer flags are typically used in gauges in which a particular value is to be marked within a circular scale. In particular, in the case of instrument cluster '' it is, for example, a speedometer (speedometer) or speed display. In order to obtain a pointer vane with a transparent optical waveguide, the pointer vane can be made, for example, of PMMA or a polycarbonate (PC) and have on a lower side a hot stamping foil which scatters light which propagates in the optical waveguide in the emission direction. Since the light guide is transparent, you can see in the dark, for example, a night ride, only the scattering hot stamping foil, which is recognized due to their scattering property only as a diffuse line. Therefore, it may take an undesirable amount of time for a driver to focus on the pointer when switching from the road to the instrument cluster.

DE 10 2008 011 062 A1 describes a multicolor pointer for a measuring element which can generate at least two colors of light from a light source with a single color. The light is colored by means of a foil.

From DE 36 28 540 A1 a pointer for a display instrument is known, which has the shape of an isosceles triangle in cross section, so that a color layer on the underside of different viewing directions

CONFIRMATION COPY can be seen on the pointer by refraction and total reflection of the radiation input in the pointer.

From JP 6281751 A a pointer for a display instrument is known, in whose transparent material a fluorescent substance is mixed. A curved gutter scatters the fluorescent light into the environment.

The invention has for its object to provide in a display device of a motor vehicle a clearly perceptible in the dark pointer flag.

The object is solved by the subject matters of the independent claims. Advantageous developments of the invention will become apparent from the features of the dependent claims.

The invention provides a display device for a motor vehicle. The display device has a pointer vane with a transparent light conductor which is designed to receive light propagating along a propagation direction from a light input device at a light entry side and to direct the light at a light exit side into a predetermined emission direction, ie towards a viewer. radiate. In other words, the pointer vane has a particularly elongated optical fiber which extends in its longitudinal direction along the pointer vane from a pointer foot to a pointer tip. In the optical waveguide, light is irradiated at a light entrance side by the light coupling device, and the optical waveguide deflects the light toward the light emission direction, so that it exits again at its light exit side. For the deflection or scattering of the light, it is now provided according to the invention that the light guide has a spreading side which is opposite the light exit side and has a plurality of steps. These steps are arranged offset to each other transversely or perpendicularly to the direction of propagation of the light, so that each stage of the light, which enters the light guide at the light entrance side, is irradiated independently of any other stage.

The display device according to the invention has the advantage that now as a pointer flag no diffuse luminous line in the display device tion is to be seen, but a three-dimensional luminous object formed from the mutually offset, luminous stages. A driver can thus focus the pointer flag with much less effort.

Particularly preferably, the steps are also arranged one behind the other along the propagation direction, so that the steps as a whole form a cascade or staircase one after the other by their offset transversely to the direction of propagation and their arrangement along the propagation direction. This results in a particularly pronounced depth effect when viewing the pointer flag.

An advantageous development provides that the steps have a rough surface structure and / or scattering elements integrated in a material of the light guide and / or a reflective, opaque coating and / or a fluorescent material. This has the advantage that the steps appear particularly bright because they divert a particularly large amount of light in the emission direction. A rough surface structure can be achieved, for example, by grinding the optical waveguide or by a correspondingly rough tool shape when creating the optical waveguide, for example by injection molding or embossing the optical waveguide. As a scattering body, for example, granules of reflective bodies, such as mother of pearl, may be provided. For example, a reflective finish may be based on chromium or a lacquer, e.g. provided with white paint. The fluorescent material may be integrated into the material of the light guide or applied to the surface of the light guide.

The steps preferably have an oblique position with respect to the propagation direction of the light on the one hand and the emission direction on the other hand. In other words, a surface normal of the steps having a vector of the propagation direction preferably includes an angle which is in a range of 5 degrees to 85 degrees, particularly 5 degrees to 45 degrees. As a result, the steps appear as depth offset, wide, luminous stripes in the pointer flag.

With regard to the position of the light entry side and the orientation of the steps, there are two principal embodiments in the display device according to the invention, namely a lateral illumination on the one hand and a longitudinal illumination on the other hand. In the case of the lateral illumination, it is provided that the light guide entry side extends along a longitudinal extension direction of the pointer vane from a pointer foot to a pointer tip. At the pointer foot, the pointer flag can be arranged a rotatably mounted pointer shaft. The pointer tip can be moved over a scale by turning the pointer shaft. The light input device thus also extends on this longitudinal side of the pointer flag from the pointer foot to the pointer tip. The light coupling device has a light-tight socket element, in which a propagation region is integrated, for example with an optical fiber. The propagation area is open to the light entry side. The light is thus distributed in the propagation region along the longitudinal extension direction of the pointer flag and enters the light guide laterally, that is to say perpendicularly to the longitudinal extension direction. The propagation direction, along which the light enters the light guide, is therefore perpendicular to the longitudinal direction. Accordingly, the steps extend along the longitudinal extension direction from the pointer foot to the pointer tip. This results in the advantage that light can be distributed in the light guide particularly homogeneous and thus the pointer flag shines particularly homogeneous.

In order to distribute the light in the propagation area within the socket element, a further development provides that an optical fiber is arranged in the propagation area and / or a wall of the socket element has a specular or light-scattering coating and / or a fluorescent material. The reflective coating of the inside of the socket element can be achieved for example by chromium or a mirror foil. Light-scattering coatings can be achieved for example by a lacquer, for example white color, or by roughening the surface. The refinements make it possible to transport the light from a light source into the light guide of the pointer vane in a particularly low-loss manner.

In the case of the lateral illumination, there is a particularly preferred embodiment in which the light is coupled in not only from one light entry side, but the light guide is designed to light propagating along a further propagation direction from another light input device on a further light entry side opposite the light entry side receive. In other words, therefore, light can penetrate from both longitudinal sides of the light guide into this. There are on the spread side, so the scaled towards the underside of the light guide mirror-symmetrical to the stages further steps provided that scatter the light, which enters through the other light entrance side, also towards the propagation direction. The light can be transported or guided to the further light entry side through a further socket element. In other words, in this embodiment, the pointer flag is designed such that a light guide has on its two longitudinal sides in each case a socket element for scattering light in the longitudinal sides of the light guide.

In the second illumination technique, the longitudinal illumination, it is provided that the light entry side is formed on the pointer foot and the direction of propagation of the incoming light along the longitudinal extension of the pointer from the pointer foot to the pointer tip points. Correspondingly, the steps then extend perpendicular to the direction of longitudinal extension, that is to say transversely to the pointer vane. This embodiment has the advantage that the pointer flag can be illuminated in its entire width, since no light-tight socket element for guiding the light is necessary.

With regard to the generation of the light, an embodiment of the display device provides that the pointer is rotatably arranged with respect to a light source for the light by the light source is arranged adjacent to the pointer shaft of the pointer, so for example on a circuit board or board, which also has a motor may have to rotate the pointer shaft. The light source is designed to emit the light along the pointer shaft, e.g. to radiate into a pointer cap. In the pointer cap, the light coupling device can begin, which then leads the light to the light entrance side of the light guide. The light may comprise, for example, one or more light-emitting diodes. An alternative embodiment, which is not claimed separately, provides that the light source is located in the pointer cap itself.

The display device according to the invention is preferably designed as a combination instrument. It can also have more than one of the described pointer flags. Each pointer flag then belongs in particular to a pointer instrument of the display device. The invention also includes a motor vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car. The motor vehicle according to the invention is characterized by at least one display device, which in each case represents an embodiment of the display device according to the invention.

In the following an embodiment of the invention is described. 1 shows a schematic representation of an embodiment of the motor vehicle according to the invention,

2 is a schematic representation of a perspective view of a pointer of a display device of the motor vehicle of Fig. 1,

Fig. 3 is a schematic representation of another perspective

2 is a schematic representation of a cross section of the pointer of FIG. 2, FIG.

Fig. 5 is a schematic representation of another cross section of the

Pointer of Fig. 2, and

Fig. 6 is a schematic representation of a longitudinal section of a pointer of an alternative embodiment of the display device according to the invention. The exemplary embodiment explained below is a preferred embodiment of the invention. In the exemplary embodiment, however, the described components of the embodiment in each case represent individual features of the invention which are to be considered independently of one another and which also extend the invention independently of one another and thus also individually or in a different combination than the one shown as part of the invention , Furthermore, the described embodiment can also be supplemented by further features of the invention already described. In Fig. 1, a motor vehicle 10 is shown, which may be, for example, a motor vehicle, especially a passenger car, act. The motor vehicle 10 may have a display device 12, which may be configured, for example, as an instrument cluster or as a display device of a dashboard of the motor vehicle 10. The display device 12 may include a pointer instrument 14. The pointer instrument 14 may be, for example, a tachometer or a speed indicator. The pointer instrument 14 in this case displays a current value to be displayed on a scale (not shown) by means of a pointer 16. The pointer 16 may include a pointer tab 18 and a pointer cap 20 and a pointer shaft 22. The pointer shaft 22 may be rotatably connected to a shaft 24 of an electric motor 26, for example, be attached to the shaft 24. By turning the shaft 24 by means of the motor 28, the pointer shaft 22 and thus the entire pointer 16 can be rotated and thereby a pointer tip 30 of the pointer lug 18 can be aligned to a value of the scale. A pointer foot 32 of the pointer vane 18 may be disposed in the pointer cap 20. The motor 28 may be located on a printed circuit board 34. The pointer cap 20 may be executed splash-white or painted and may be designed to cover a deflection of illumination for the pointer vane 18. The illumination can be done by various options, preferably it is an illumination by means of one or more light-emitting diodes 36, which are arranged on an upper side of the printed circuit board 34, ie to the pointer 16 out. The light-emitting diodes 36 then emit their light 38 towards the pointer cap 20, where it is then coupled into the pointer vane 18 and thereby the pointer vane 18 by means of deflection and / or reflection of the light 38 in an emission direction 40 away from the scale towards a viewer is emitted.

The distribution of the light 38 in the pointer vane 18 can be done by a lateral illumination, as explained in connection with FIG. 2 to FIG. 5. An alternative is a longitudinal illumination, which will be explained in connection with FIG.

The lateral illumination, as shown in FIG. 2, provides that the pointer lug 18 has a transparent light guide 42 and a light-tight pointer sheath 44 which surrounds it laterally, transversely to the direction of propagation 40. The light guide 42 may be made of PMMA or a polycarbonate, for example. The pointer enclosure 44 may be a first version provide element 46 on one side and a second socket 48 on an opposite side of the light guide 42.

In Fig. 3, the pointer 6 is shown from a perspective of the board 34, so the light emitting diodes 16 from. The pointer foot 32 is defined toward the pointer tip 30. The socket elements 46, 48 likewise extend in the longitudinal extension direction 50 from the pointer foot 32 to the pointer tip 30 and are arranged on opposite sides of the light guide 42, thus gripping the light guide 42 and thus forming a sandwich arrangement together with the light guide 42 Light emitting diodes 36 radiated light 38 can penetrate in the region of the pointer foot 32 in a respective propagation region 52, 54 of the socket elements 46, 48. The propagation regions 52, 54 extend along the longitudinal extension direction 52 in the interior of the socket elements 46, 48, as illustrated by the cross-section in FIG. 4. A possible position along the cross section along the pointer vane 18 is illustrated in FIGS. 3 and 4.

It is shown in the cross-section of FIG. 4 that the propagation regions 52, 54 may, for example, be configured as chambers in which an optical fiber 56, 58 is arranged along the longitudinal extension direction 50 (shown in FIG. 4 as a vector in the drawing plane) can. The light which has penetrated into the propagation regions 52, 54 at the pointer base 32 propagates in the optical fibers 56, 58 along the direction of longitudinal extension 50 and exits through openings 60, 62 of the propagation regions 52, 54 toward the light guide 52. The light guide 42 has, in the region of the passage openings 60, 62, in each case a light entry side 64, 66, through which the light 38 penetrates into the light guide 42 along a respective propagation direction 68, 70. The optical waveguide 42 has two stepped, cascaded regions 76, 78 within the pointer vane 18 on a diffuser side 74 opposite the light exit side 72. The stepped areas 76, 78 may be designed such that they are visible to the respective observer by means of a structure 84 located on edges or steps 80, 82 as soon as they are illuminated by means of the light 38. The effect that results creates a three-dimensional image for the viewer and creates a depth effect within the pointer vane 18. The depth effect is on the one hand by the structuring 84 and on the other hand by a slight inclination of the end portions of the cascades 76, 78, so the stages 80, 82, generated. The steps 80, 82 are offset transversely to the direction of propagation 68, 70 of the light 38 which illuminates them, that is, one above the other in FIG. 4. The steps 80, 82 are also arranged one behind the other along the respective propagation direction 68, 70, ie, laterally relative to one another in FIG. 4, the steps 80, 82 each form a staircase leading to the direction of propagation 40.

The inclination is explained again in connection with FIG. FIG. 5 shows for a stage 80 its normal vector 86 of the step level. The step vector 86 includes with the associated propagation direction 68 an angle 88 which is greater than 0 degrees.

The illumination by means of the optical fibers 56, 58 or in general the propagation regions 52, 54, which are located laterally on the light guide 42, the light 38 is distributed in the longitudinal direction 50 along the light guide 42 and can thus penetrate into the light guide 42 and this homogeneous Illuminate the light. To cover the optical fibers 56, 58 they are covered by the light-tight pointer sheath 44. It is possible to dispense with even a pointer cap 20 or to integrate the pointer cap 20 in the component of the pointer sheath 44.

In Fig. 6, the longitudinal illumination is illustrated. In Fig. 6, the same reference numerals are used for functionally identical elements as in the preceding figures. FIG. 6 shows that the light entry surface 64 is arranged on the pointer foot 32 of the pointer vane 42 and the light 38 reaches the light entry surface 64 via a pointer cap 20, which represents a light guide device in this case, and along the longitudinal extension direction 50 of FIG Pointer flag 42 penetrates into the material of the pointer flag. At stages 80, which may likewise have the described structure 84, the light at the scattering side 74 of the pointer vane 42 can be refracted in the direction of the emission direction 40, so that the light 38 exits the light conductor 42 on the light exit side 72 in the direction of the observer. In the pointer shown in Fig. 6, no pointer enclosure 44 is necessary for distributing the light. The light coupling takes place below the pointer cap.

Overall, the example shows how by the invention a 3-dimensional representation of pointer instruments in the instrument cluster by gradation or cascades and structuring within the pointer flag can be achieved.

Claims

CLAIMS:

A display device (12) for a motor vehicle (10), comprising a pointer tab (18) with a transparent light guide (42), which is adapted to light (38) propagating along a propagation direction (68) on a light entry side (64). from a light input device (20, 46) and to emit the light (38) at a light exit side (72) in a radiation direction (40), characterized in that

the optical waveguide (42) has a spreading side (74) which is opposite the light exit side (72) and has a plurality of steps (80) arranged offset to one another transversely to the propagation direction (68).

2. Display device (12) according to claim 1, wherein the steps (80) along the propagation direction (68) are arranged one behind the other, so that the steps (80) form a cascade (76).

3. Display device (12) according to one of the preceding claims, wherein the steps (80) have a rough surface structure (84) and / or scattering elements (84) integrated in a material of the light guide (42) and / or a reflective coating (84) and or a fluorescent material (84).

A display device (12) according to any one of the preceding claims, wherein a respective surface normal (86) of the steps (80) having a vector of propagation direction (68) includes an angle (88) ranging from 5 ° to 85 °, in particular 5 ° to 45 °.

5. Display device (12) according to one of the preceding claims, wherein the light entrance side (64) along a longitudinal extension direction (50) of the pointer vane (18) from a pointer foot (32) extends to a pointer tip (30) and the light input device ( 46) has a light-tight, on the light inlet side (64) arranged and one to the light entry side (64) open transparent propagation region (52) surrounding socket member (46).

6. Display device (12) according to claim 5, wherein an optical fiber (56) is arranged in the propagation region (52) and / or a wall of the socket element (46) has a specular or glossy surface. che and / or a fluorescent material.

7. A display device (12) according to claim 5 or 6, wherein the light guide (42) is adapted to light (38) propagating along a further propagation direction (70) on a further light entry side (66) opposite the light entry side (64). from a further light coupling device (48) to receive and on the spreading side (74) mirror-symmetrical to the steps (80) further steps (82) are provided.

8. Display device (12) according to one of claims 1 to 4, wherein the light entry side (64) is arranged on a pointer foot (32) and the propagation direction (68) along a longitudinal extension (50) of the pointer flag (18) from the pointer foot (32). to a pointer tip (30) points.

9. Display device (12) according to one of the preceding claims, wherein the pointer vane (18) with respect to a light source (36) for the light (38) is rotatably arranged by the light source (36) adjacent to a pointer vane (18) carrying pointer shaft (18). 22) and the light (38) along the pointer shaft (22) is designed to radiate.

10. motor vehicle (10) with at least one display device (12) according to any one of the preceding claims.