Head-up display

Abstract

Provided is a head-up display with which it is possible to achieve space savings. A head-up display 1 according to an embodiment is provided with: a lower case 55 having a case-side contact portion 81; and a heat sink 20 having a heat sink-side contact portion 91, the heat sink 20 being supported at the sink-side contact portion 91 being screw-fixed to the case-side contact portion 81. The case-side contact portion 81 comprises: a positioning concave portion 82 which is concave with respect to the case-side contact portion 81; and a case-side screw hole 85 formed in the positioning concave portion 82. The heat sink-side contact portion 91 comprises: a positioning convex portion 92 which is convex with respect to the heat sink-side contact portion 91 and is accommodated in the positioning concave portion 82; and a heat sink-side screw hole 95 formed in the positioning convex portion 92 along the protruding direction of the positioning convex portion 92.

Description

Technical Field

[0001] The present disclosure relates to a head-up display mounted on a vehicle or the like.

Background Art

[0002] A head-up display has a case that houses a display device and a mirror in an internal space. Various structures for fixing and supporting components such as the display device are provided in the case. When fixing a component to the case, a method of temporarily fixing and then screwing may be employed using positioning structures provided on the case and the component respectively.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When both a positioning structure and a screwing structure are provided on the case and the component, it is necessary to secure respective regions for these. Along with this, the dimensions of the case and the component become large, which may impede space saving of the head-up display.

[0005] The present disclosure has been made in consideration of such circumstances, and an object thereof is to provide a head-up display capable of achieving space saving.

Means for Solving the Problems

[0006] In order to solve the above-described problems, the head-up display of the present disclosure includes a support member having a support-side contact portion, and a supported member having a supported-side contact portion and supported by being screwed to the support-side contact portion at the supported-side contact portion. The support-side contact portion has a concave positioning recess with respect to the support-side contact portion and a support-side screw hole formed in the positioning recess. The positioning recess has a first recess and a second recess. The first concave portion is formed in a substantially perfect circular shape when viewed in the axial direction of the screw. The second recess When viewed in the axial direction of the screw is formed in a substantially oval shape having a major axis along the direction toward the first recess. The supported-side contact portion is convex with respect to the supported-side contact portion and has a positioning convex portion accommodated in the positioning recess and a supported-side screw hole formed in the positioning convex portion along the convex direction of the positioning convex portion.

Advantages of the Invention

[0007] In the head-up display of the present disclosure, space saving can be achieved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0009] A first embodiment of the head-up display of the present disclosure will be described with reference to the accompanying drawings. The head-up display of the present disclosure is mounted on a vehicle such as an automobile.

[0010] (First Embodiment) FIG. 1 is an external perspective view showing one embodiment of the head-up display of the present disclosure and explaining the overall configuration. FIG. 2 is a plan view of the head-up display 1 with the upper case 51 removed, as viewed from above.

[0011] In the following description, "front (front face)", "rear (rear face)", "upper", "lower", "right", and "left" follow the definitions "Fr.", "Re.", "To.", "Bo.", "R", and "L" in FIGS. 1 to 3.

[0012] The head-up display 1 (hereinafter referred to as HUD1) is disposed within the instrument panel of an automobile. The HUD1 mainly includes a display device 10, a heat sink 20, a flat mirror 30, a concave mirror 40, a case 50, and a circuit board 60. The HUD1 reflects the display light L representing the display image displayed by the display device 10 with the flat mirror 30 and the concave mirror 40 that constitute a relay optical system, and irradiates the windshield of the automobile, which is an example of a transmissive-reflective portion. The viewer (mainly the driver) can visually recognize the virtual image of the display image superimposed on the actual scene in front of the vehicle.

[0013] The display device 10 outputs the display light L. The display device 10 is, for example, a TFT (Thin Film Transistor) type liquid crystal display device. The display device 10 has a backlight unit and a liquid crystal display panel. In particular, the backlight unit has a light source substrate that serves as a heat source.

[0014] The heat sink 20 is fixed to the display device 10 and dissipates the heat generated by the light source substrate (display device 10). The heat sink 20 is thermally connected via a heat conduction sheet. The heat conduction sheet is provided between the light source substrate and the heat sink 20 and efficiently transfers the heat of the light source to the heat sink 20.

[0015] The heat sink 20 has a base 21 and a plurality of heat radiation fins 22. The base 21 has a placement surface for the heat conduction sheet. The heat radiation fins 22 extend substantially orthogonally to this surface from the surface of the base 21 opposite to the placement surface of the heat conduction sheet. A part of the heat radiation fins 22 is exposed from the opening 56 of the lower case 55. Further, the heat sink 20 is fixed to the lower case 55 with screws 100 (details will be described later).

[0016] The heat sink 20 is a molded product formed of a high thermal conductivity resin material. In the present disclosure, the high thermal conductivity resin is a resin such as nylon blended with a high thermal conductivity filler such as a ceramic filler, and is defined as a mixed resin having a thermal conductivity (thermal conductivity coefficient) of at least 1.0 W / (m·K) or more. The high thermal conductivity filler is preferably an insulating filler such as aluminum oxide, boron nitride, or aluminum nitride, which is a kind of ceramics. When higher heat dissipation is required, a filler having no electrical insulation property such as aluminum, copper, or graphite may be selected as the high thermal conductivity filler.

[0017] As an example of the thermal conductivity in each configuration, the thermal conductivity of a single nylon resin is 0.22 to 0.43 W / (m·K). On the other hand, the thermal conductivity of a high thermal conductivity resin obtained by mixing a ceramic filler having electrical insulation property with a nylon resin is about 5 W / (m·K). Further, the thermal conductivity of a high thermal conductivity resin obtained by mixing a filler having no electrical insulation property with a nylon resin is about 50 W / (m·K). That is, the high thermal conductivity resin has higher thermal conductivity than ordinary resins.

[0018] The plane mirror 30 (reflector) has, for example, a base material made of a synthetic resin material and a reflective film formed on the surface of the base material by vapor deposition or the like. The plane mirror 30 reflects the display light L output from the display device 10 toward the concave mirror 40.

[0019] The concave mirror 40 (reflector) has, for example, a base material made of a synthetic resin material and a reflective film formed on the surface of the base material by means such as vapor deposition. The concave mirror 40 reflects the display light L reflected by the plane mirror 30 toward the windshield. The concave mirror 40 has a function as a magnifying glass, magnifies the display image, and reflects it onto the windshield. Thereby, the viewer visually recognizes a virtual image in which the display image is magnified. The concave mirror 40 rotates around a rotation axis by an actuator (not shown). The actuator adjusts the angle of the concave mirror 40 by rotating the concave mirror 40, adjusts the irradiation position of the display light L, or adjusts the angle so that external light is not reflected by the concave mirror 40 toward the display device 10.

[0020] The case 50 has an upper case 51 and a lower case 55. The case 50 forms an internal space 50a by combining the upper case 51 and the lower case 55. The display device 10, the plane mirror 30, and the concave mirror 40 are accommodated in this internal space 50a. Further, the internal space 50a of the case 50 serves as an optical path for the display light L. The upper case 51 and the lower case 55 are made of, for example, a synthetic resin (e.g., polypropylene) having black light-shielding properties.

[0021] The upper case 51 has an opening 52 in a portion facing the windshield. The opening 52 is covered with a light-transmitting cover 53 having light-transmitting properties. The light-transmitting cover 53 transmits the display light L reflected by the concave mirror 40.

[0022] The lower case 55 has a structure for attaching the display device 10, the plane mirror 30, and the concave mirror 40 on the inner surface 55a forming the internal space 50a. Further, the lower case 55 has a structure for attaching the circuit board 60 in a region facing substantially downward on the outer surface 55b, which is the surface opposite to the inner surface 55a.

[0023] The circuit board 60 is a printed circuit board on which a control unit for controlling the operation of the display device 10 and the like is mounted. The control unit has a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc., and executes predetermined arithmetic processing according to a program written in the ROM, for example. The control unit acquires various vehicle information from, for example, the vehicle's ECU (Electronic Control Unit). The control unit drives the display device 10 based on the acquired information.

[0024] The circuit board 60 is disposed on the outer surface 55b of the lower case 55. The circuit board 60 is covered and protected by a board cover (not shown). The board cover is fixed to the lower case 55 together with the circuit board 60 by screws.

[0025] Next, a fixing structure formed on the lower case 55 and the heat sink 20 for fixing the heat sink 20 to the lower case 55 will be described in detail. FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2. In FIG. 3, for the purpose of explaining the fixing structure, a part of the configuration of the heat sink 20 is shown omitted.

[0026] The fixing structure 80 on the lower case 55 (support member) side has a case-side contact portion 81, a positioning recess 82, and a case-side screw hole 85.

[0027] The case-side contact portion 81 (support-side contact portion) has a front-side contact portion 81a and a rear-side contact portion 81b, which are provided symmetrically with respect to the substantially front-rear direction. The case-side contact portion 81 is a flat surface region that is substantially orthogonal to the vertical direction.

[0028] The positioning recess 82 is formed in a concave shape with respect to the case-side contact portion 81. The rear-side positioning recess 82b (first recess) formed in the rear-side contact portion 81b is formed in a substantially circular shape when viewed from above (axial direction view). The front-side positioning recess 82a (second recess) formed in the front-side contact portion 81a is formed in a substantially oval shape having a major axis along the direction facing the rear-side positioning recess 82b when viewed from above.

[0029] The case-side screw hole 85 (support-side screw hole) is a female screw formed with a thread that fits with the thread of the screw 100. The case-side screw hole 85 is formed downward from the bottom surface 83, which is the surface facing the opening end surface on the case-side contact portion 81 side of the positioning recess 82. The case-side screw hole 85 on the rear-side positioning recess 82b side is formed concentrically with the circular rear-side positioning recess 82b (the central axes coincide). The case-side screw hole 85 on the front-side positioning recess 82a side is formed concentrically with the oval front-side positioning recess 82a (the central axes coincide).

[0030] The fixing structure 90 on the heat sink 20 (member to be fixed) side is provided on both end faces 21a facing in the front-rear direction of the base portion 21. The fixing structure 90 has a heat sink-side contact portion 91, a positioning projection 92, and a heat sink-side screw hole 95.

[0031] The heat sink-side contact portion 91 (contact portion on the supported side) is a flat surface-like region (member) that protrudes substantially orthogonally from both end faces 21a of the heat sink 20 and is substantially orthogonal in the vertical direction. The heat sink 20 is physically contacted and supported by the case-side contact portion 81 at the heat sink-side contact portion 91.

[0032] The positioning projection 92 protrudes downward with respect to the heat sink-side contact portion 91 and has a substantially cylindrical shape. The diameter of the positioning projection 92 is set so as to have a gap with the positioning recess 82. Further, the positioning projection 92 has a convex amount (vertical length from the lower surface 91a of the heat sink-side contact portion 91) that is smaller than the recess amount of the positioning recess 82 (vertical length from the case-side contact portion 81). Thereby, in terms of design, the positioning projection 92 is completely accommodated in the positioning recess 82 in a non-contact state with the positioning recess 82.

[0033] The heat sink side screw hole 95 (the screw hole on the supported side) is formed in the positioning convex portion 92 along the convex direction of the positioning convex portion 92. Specifically, the heat sink side screw hole 95 is formed at the position where the positioning convex portion 92 on the heat sink side contact portion 91 is provided. The heat sink side screw hole 95 is formed concentrically with the cylindrical positioning convex portion 92 (the central axes coincide). The heat sink side screw hole 95 has a diameter larger than that of the case side screw hole 85 and has no thread.

[0034] Such a HUD 1 can achieve space saving by having the fixing structures 80 and 90. That is, compared with a HUD having an uneven structure for positioning at a location different from the screw hole as a comparative example, the HUD 1 in the present embodiment forms the screw holes 85 and 95, the positioning convex portion 92, and the positioning concave portion 82 along the axial direction (vertical direction) of the screw 100. Thereby, the HUD 1 does not need to secure a space for providing the positioning concave portion 82 and the positioning convex portion 92 in addition to the space for providing the screw holes 85 and 95 on the front-rear, left-right plane. Therefore, the HUD 1 can achieve space saving, and can also achieve miniaturization of the HUD 1 and improvement of the design freedom.

[0035] Also, the heat sink 20 is formed of a high thermal conductivity resin material having a lower strength than metal. In response to this, the diameter of the heat sink side screw hole 95 is made larger than the diameter of the case side screw hole 85, that is, the diameter of the screw 100. Also, the convex amount of the positioning concave portion 82 is made smaller than the concave amount of the positioning concave portion 82. Further, the diameter of the positioning convex portion 92 is set so that a gap is formed between the positioning concave portion 82 and the positioning convex portion 92. Thereby, when screwing, it is possible to suppress the heat sink 20, the screw 100, and the lower case 55 from coming into contact and unnecessary force from being applied to the heat sink 20, and it is possible to suppress breakage of the heat sink 20 and the like.

[0036] Although some embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

[0037] For example, although an example in which the support member is the lower case 55 and the supported member is the heat sink 20 has been described, the present invention is not limited thereto and can be applied between various two members. For example, the support member may be the lower case 55 and the supported member may be the display device 10. Further, the support member may be the display device 10 and the supported member may be the heat sink 20.

[0038] The gap between the positioning convex portion and the positioning concave portion is not essential and they may be in contact.

Description of Reference Numerals

[0039] 1 Head-up Display (HUD) 10 Display device 20 Heat sink (supported member) 21 Base 21a Both end faces 22 Radiation fins 30 Plane mirror 40 Concave mirror 50 Case 50a Internal space 51 Upper case 52 Opening 53 Translucent cover 55 Lower case (support member) 55a Inner surface 55b Outer surface 56 Opening 60 Circuit board 80 Fixing structure 81 Case-side contact portion (support-side contact portion) 81a Front-side contact portion 81b Rear-side contact portion 82 Positioning recess 82a Front-side positioning recess (second recess) 82b Rear-side positioning recess (first recess) 83 Bottom surface 85 Case-side screw hole (support-side screw hole) 90 Fixing structure 91 Heat sink-side contact portion (portion to be supported contact portion) 91a Lower surface 92 Positioning protrusion 95 Heat sink-side screw hole (portion to be supported screw hole) 100 Screw L Display light

Claims

1. a support member having a support-side contact portion; a supported member having a supported-side contact portion and supported by being screwed to the support-side contact portion at the supported-side contact portion; the support-side contact portion has a concave positioning recess with respect to the support-side contact portion and a support-side screw hole formed in the positioning recess; the positioning recess has a first recess and a second recess; the first recess is formed in a substantially circular shape in a view in the axial direction of the screw; the second recess is formed in a substantially oval shape having a major axis along a direction toward the first recess in a view in the axial direction of the screw; the supported-side contact portion is convex with respect to the supported-side contact portion and has a positioning protrusion accommodated in the positioning recess and a supported-side screw hole formed in the positioning protrusion along the convex direction of the positioning protrusion, a head-up display.

2. a central axis of the positioning recess coincides with a central axis of the support-side screw hole; a central axis of the positioning protrusion coincides with a central axis of the supported-side screw hole, the head-up display according to claim 1.

3. the supported-side screw hole has a diameter larger than a diameter of the support-side screw hole, the head-up display according to claim 1.

4. the positioning protrusion has a convex amount smaller than a concave amount of the positioning recess, the head-up display according to claim 1.

5. the positioning protrusion has a diameter set to have a gap with the positioning recess, the head-up display according to claim 1.

6. a display device that outputs display light; a heat sink that dissipates heat generated by the display device; a reflecting mirror that reflects the display light output from the display device; a case that houses the display device and the mirror; the support member is the case; The head-up display according to claim 1, wherein the supported member is the heat sink.

Images