Head-up display device

Abstract

To provide a head-up display device capable of suppressing noise and achieving weight reduction. [Solution] A head-up display device 100 includes a display device 10 that emits display light L and a concave mirror 30 that reflects the display light L, and projects the display light L onto the windshield. The head-up display device 100 includes a case 60 that supports the display device 10 and the concave mirror 30, a control board 11 that is installed on the outer surface of the case 60 and has a controller 11a that controls the display device 10, a cable 13 that electrically connects the control board 11 and the display device 10, a metal cover 61 that is attached to the case 60 so as to cover the control board 11, and a resin cover 62 that is attached to the case 60 so as to cover at least the cable 13. The metal cover 61 and the resin cover 62 have overlapping portions 61c, 62c that partially overlap each other.

Description

[Technical Field]

[0001] The present disclosure relates to a head-up display device. [Background technology]

[0002] The head-up display device described in Patent Document 1 includes a display device that emits display light, a concave mirror that reflects the display light from the display device, a main control board that controls the display device, and a housing formed of a non-transparent resin material or a metal material that houses the display device, the concave mirror, and the main control board, and this housing includes a lower cover that covers the display device and a board cover that covers the main control board (see paragraph 0012 and Figure 2 of Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2024-75830 Summary of the Invention [Problem to be solved by the invention]

[0004] In the configuration described in Patent Document 1, if the bottom cover and board cover are made of a metal material, the noise shielding function is stronger than if they were made of a resin material, but the weight increases and it is difficult to form complex shapes with metal, making it more likely that gaps will form through which noise can enter and exit. On the other hand, if the bottom cover and board cover are made of a resin material, the weight can be reduced and the freedom in shape increases, making gaps less likely to occur, but the noise shielding function of the material itself is reduced. As described above, it has been difficult to achieve both noise countermeasures and weight reduction.

[0005] The present disclosure has been made in consideration of the above-described circumstances, and aims to provide a head-up display device that can reduce noise and achieve weight reduction. [Means for solving the problem]

[0006] In order to achieve the above object, a head-up display device according to the present disclosure includes: A head-up display device comprising: a display device that emits display light; and a mirror that reflects the display light, and projects the display light onto a projection member, a case supporting the display device and the mirror; a circuit board having a control unit that is installed on an outer surface of the case and controls the display device; a wiring portion that electrically connects the circuit board and the display device; a metal cover attached to the case so as to cover the circuit board; a resin cover attached to the case so as to cover at least the wiring portion, The metal cover and the resin cover have overlapping portions where they at least partially overlap each other. [Effects of the Invention]

[0007] According to the present disclosure, noise countermeasures and weight reduction can be achieved. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of a vehicle equipped with a head-up display device according to an embodiment of the present disclosure. [Figure 2] 1 is a schematic cross-sectional view of a head-up display device according to an embodiment of the present disclosure. [Figure 3] FIG. 2 is a bottom view of a head-up display device according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a bottom view of a head-up display device according to an embodiment of the present disclosure, with a metal cover and a resin cover removed. [Figure 5] 1 is a perspective view of a portion of a head-up display device according to an embodiment of the present disclosure. [Figure 6] 1 is a perspective view of a portion of a head-up display device with a resin cover removed according to an embodiment of the present disclosure. FIG. [Figure 7] FIG. 2 is a bottom view of a portion of a head-up display device with a metal cover removed according to an embodiment of the present disclosure. [Figure 8] 1 is a perspective view of a portion of a head-up display device according to an embodiment of the present disclosure. [Figure 9] FIG. 2 is a perspective view of a metal cover and a resin cover according to an embodiment of the present disclosure. [Figure 10] FIG. 2 is a perspective view of a resin cover according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] A head-up display device according to an embodiment of the present disclosure will be described with reference to the drawings. As shown in Fig. 1, the head-up display device 100 is installed in the dashboard of a vehicle 200. The head-up display device 100 emits display light L that displays an image toward a windshield 201, which is an example of a projection target member of the vehicle 200. The display light L is reflected by the windshield 201 and reaches a viewer 1 (mainly the driver of the vehicle 200). As a result, the head-up display device 100 displays a virtual image V so as to be superimposed on an actual scene seen through the windshield 201.

[0010] As shown in FIG. 2, the head-up display device 100 includes a display device 10 that emits display light L, a concave mirror 30, a case 60, a metal cover 61, a resin cover 62, and a control board 11. In the following description, the vehicle width direction is defined as the X direction, the up-down direction is defined as the Y direction, and the vehicle front-rear direction is defined as the Z direction.

[0011] The concave mirror 30 reflects the display light L from the display device 10 toward the windshield 201 (see FIG. 1) while magnifying the light.

[0012] The display device 10 includes an illumination device 70 that emits illumination light IL, a display unit 80 that receives the illumination light IL and emits display light L, and cables 13 and 15. The lighting device 70 includes a plurality of light sources 75 a, a light source substrate 75 , a lighting case 74 , and a heat sink 79 . The plurality of light sources 75a are made up of LEDs (Light Emitting Diodes) and are arranged on the mounting surface of the light source substrate 75. The plurality of light sources 75a emit illumination light IL. The lighting case 74 is formed in a cylindrical shape so as to surround and hold the periphery of the light source substrate 75 and a group of light distribution lenses (not shown). The heat sink 79 dissipates heat generated from the light source substrate 75 to the outside. The heat sink 79 is formed in an area extending from the rear surface of the light source substrate 75 (the surface opposite to the mounting surface) to above the lighting device 70.

[0013] As shown in FIG. 2, the display unit 80 includes a display panel 84, a relay board 83, and a display case 85.

[0014] The display panel 84 is, for example, a TFT (Thin Film Transistor) liquid crystal display panel, and emits display light L upon receiving illumination light IL. The relay board 83 is electrically connected between the display panel 84 and the control board 11 via a pair of cables 13 and 15. The relay board 83 is a flexible printed circuit (FPC). The cable 13 is electrically connected between the relay board 83 and the control board 11, and the cable 15 is electrically connected between the relay board 83 and the display panel 84. The cables 13 and 15 are strip-shaped flexible flat cables. 4, cable 13 is bent into an L-shape, and both ends of cable 13 are inserted into connectors 13c, 83c of control board 11 and relay board 83, respectively. Connector 13c of control board 11 extends in the X direction and is located at the end of the lower surface of control board 11 that faces relay board 83. Connector 83c of relay board 83 extends in the X direction and is located at the end of the lower surface of relay board 83 that is closest to connector 13c, of the two ends that extend in the Z direction.

[0015] The display case 85 is made of a light-blocking resin or metal, and is configured in a substantially rectangular tubular shape that surrounds the outer periphery of the display panel 84. A relay board 83 is provided on the outer lower surface of the display case 85.

[0016] The control board 11 is a printed circuit board on which a control unit 11a is mounted. The control unit 11a is made up of a CPU (Central Processing Unit) and a GDC (Graphics Display Controller). The control board 11 is electrically connected to the relay board 83 via the cable 13, and is also electrically connected to the light source board 75 via a cord 14 (see FIG. 4), which is a type of electric wire. The control board 11 outputs a control signal for controlling the display panel 84 to the display panel 84 via the cable 13, the relay board 83, and the cable 15, and outputs a control signal for controlling the light source 75a to the light source 75a via the cord 14 and the light source board 75.

[0017] 2, the case 60 is a hollow, approximately rectangular parallelepiped. The case 60 includes a lower case portion 60a and an upper case portion 60b. The lower case portion 60a, the upper case portion 60b, and the metal cover 61 are made of metal. The lower case portion 60a and the upper case portion 60b are not limited to being made of metal, but may also be made of resin.

[0018] The lower case portion 60a is in the shape of a box with a bottom and an opening on the top side, and houses the concave mirror 30 and has the display device 10 attached thereto. 3 and 4, a board accommodating section 60c that accommodates the control board 11 is formed on the outer bottom surface of the lower case section 60a. The board accommodating section 60c is formed to surround the outer circumferential side surface of the control board 11 and opens downward. The control board 11 is provided in the board accommodating section 60c in a direction along the outer bottom surface of the lower case section 60a and is fixed to the lower case section 60a together with the metal cover 61 with a plurality of screws B.

[0019] As shown in Fig. 2, the upper case portion 60b is formed as a lid that closes the opening of the lower case portion 60a. The upper case portion 60b has an opening formed in a position facing the windshield 201 (see Fig. 1). The upper case portion 60b has a window portion 60w formed in a curved plate shape that closes the opening. The window portion 60w is made of a translucent resin material such as acrylic, through which display light L passes.

[0020] 2, the metal cover 61 covers the control board 11 by closing the opening of the board accommodating portion 60c. The metal cover 61 is manufactured by press-drawing a single plate. The metal cover 61 is made of a metal such as magnesium or aluminum.

[0021] As shown in FIGS. 6 and 8, the metal cover 61 includes a recessed portion 61a, a metal wrap portion 61c, and an outer frame portion 61d having a plurality of screw fastening portions 61b. The recessed portion 61a is formed in a concave shape relative to the lower surface of the control board 11. The recessed portion 61a prevents components mounted on the control board 11 from coming into contact with the metal cover 61. The recessed portion 61a includes a ceiling wall portion 61a1 extending on the XZ plane, and a side wall portion 61a2 curved downward from the outer periphery of the ceiling wall portion 61a1.

[0022] The outer frame portion 61d surrounds the outer periphery of the recessed portion 61a and has a flat frame shape with a portion of the outer periphery of the metal cover 61 discontinued. The outer frame portion 61d has a generally rectangular frame plate shape that is long in the X direction. The metal wrap portion 61c is recessed in the same manner as the recess portion 61a in the portion where the outer frame portion 61d is discontinued, and is formed so as to communicate between the internal space of the recess portion 61a and the external space of the metal cover 61. The metal wrap portion 61c has a tunnel shape extending in the Z direction toward the resin cover 62, and covers the end portion 13a of the cable 13 on the control board 11 side.

[0023] As shown in FIG. 6, the metal wrap portion 61c includes a ceiling wall portion 61c1 and two side wall portions 61c2 and 61c3. The ceiling wall 61c1 extends on the XZ plane. The two side walls 61c2 and 61c3 extend in a curved manner in the Y direction (upward) from both ends of the ceiling wall 61c1 in the X direction. The angle of the side wall 61c3 relative to the ceiling wall 61c1 is larger than the angle of the side wall 61c2 relative to the ceiling wall 61c1, forming an obtuse angle. In this example, since the side walls 61c2 and 61c3 are curved, the curvature of the side wall 61c2 is larger than the curvature of the side wall 61c3.

[0024] A plurality of screw fastening portions 61b are formed at each corner of the outer frame portion 61d, and screws B are inserted through the screw fastening portions 61b. The screws B are screwed together with the control board 11 into the outer bottom surface of the lower case portion 60a, thereby fixing the metal cover 61 to the lower case portion 60a.

[0025] 3 to 5, the resin cover 62 is attached to the outer bottom surface of the lower case portion 60a so as to cover the lower surface side of the display device 10 attached to the lower case portion 60a. Specifically, the resin cover 62 covers the lower surfaces of the relay board 83, the cable 13, the cord 14, the lighting case 74, and the display case 85.

[0026] The resin cover 62 is aligned in the Z direction (rearward of the vehicle) with the metal cover 61. When viewed from the Z direction, the metal cover 61 and the resin cover 62 are formed to overlap at an overlapping region A (see FIG. 3), which is a part of the metal cover 61 and the resin cover 62. The size of the resin cover 62 in the X direction is larger than the size of the metal cover 61 in the X direction. The size of the resin cover 62 in the Z direction is larger than the size of the metal cover 61 in the Z direction. The resin cover 62 has a more complicated shape than the metal cover 61, and is a shape that is difficult to achieve by press working of a metal plate. Examples of shapes that are difficult to achieve by press working include forming a recess 62d1 (see FIG. 10) for wiring in a ceiling wall portion 62d (described later) and forming a rib 62r (described later). The resin cover 62 is formed to be thicker than the metal cover 61 .

[0027] The resin cover 62 is formed from a resin that has electromagnetic wave shielding properties but no surface conductivity. Here, "no conductivity" refers to a resistance value of 10 kΩ or greater. The resin cover 62 is primarily composed of a resin such as polypropylene (PP) or polybutylene terephthalate (PBT), and is filled with carbon-containing powder or fibers to enhance the resin's shielding properties. The carbon fiber content and size of the filled carbon fibers determine whether the resin cover is filled with larger (longer) fibrous carbon fibers, increasing the resin cover's conductivity and enabling surface conductivity. Using finer fibers and lowering the carbon fiber content eliminates the resin cover's surface conductivity. The resin cover 62 does not have to have a shielding property, and in this case, the resin does not have to contain powder or fiber containing carbon.

[0028] The resin cover 62 is recessed relative to the display device 10, the cable 13, and the cord 14. As shown in FIGS. 8 to 10, the resin cover 62 includes a ceiling wall portion 62d, a side wall portion 62e, a plurality of screw fastening portions 62b, a resin wrap portion 62c, a rib 62r, and a pressing portion 62f. The ceiling wall portion 62d extends on the XZ plane and has a generally rectangular plate shape that is long in the X direction. The side wall portion 62e stands upright from the outer peripheral edge portion of the ceiling wall portion 62d. The ribs 62r are formed in a grid pattern on the surface of the ceiling wall portion 62d facing the display device 10. The ribs 62r are formed mainly for the purpose of reinforcing the resin cover 62. The plurality of screw fastening portions 62b are arranged on the outer periphery side of the resin cover 62, and screws B are inserted through them. The screws B are screwed into the outer bottom surface of the lower case portion 60a, thereby fixing the resin cover 62 to the lower case portion 60a.

[0029] The resin wrap portion 62c is formed so as to cover the metal wrap portion 61c from below (from above in FIG. 8). 7, the resin wrap portion 62c is located at one of the four corners of the ceiling wall portion 62d that faces the control board 11, and has a tunnel shape extending in the Z direction. The inner surface of the resin wrap portion 62c has substantially the same shape as the outer surface of the metal wrap portion 61c. These inner and outer surfaces are in contact with each other without any gaps. 8, the resin lap portion 62c and the metal lap portion 61c are wrapped in lap regions C on the opening end sides in the Z direction. The resin lap portion 62c is formed so as to protrude downward (upward in FIG. 8) from the ceiling wall portion 62d.

[0030] As shown in FIGS. 8 and 10, the resin wrap portion 62c includes a ceiling wall portion 62c1 and two side wall portions 62c2 and 62c3. The upper surface of the ceiling wall 62c1 is in tight contact with the lower surface of the ceiling wall 61c1 of the metal wrap portion 61c. The upper surfaces of the two side walls 62c2 and 62c3 are in tight contact with the lower surfaces of the side walls 61c2 and 61c3 of the metal wrap portion 61c.

[0031] 9 and 10, the pressing portion 62f presses upward a part of the outer peripheral edge portion (more precisely, a corner portion of the outer frame portion 61d) of the metal cover 61. The pressing portion 62f is located next to the resin wrap portion 62c and is substantially L-shaped on the XZ plane.

[0032] Next, the process of assembling the display device 10 and the control board 11 into the lower case portion 60a will be described. As shown in FIG. 4, the display device 10 and the control board 11 are mounted in the lower case portion 60a. From this state, as shown in FIG. 6, the control board 11 is covered with the metal cover 61, and the metal cover 61 and the control board 11 are fixed to the lower case portion 60a with a plurality of screws B. Next, with the display device 10 covered with the resin cover 62, the resin cover 62 is fixed to the lower case portion 60a with a plurality of screws B. This results in a state in which the resin wrap portion 62c overlaps the metal wrap portion 61c. This completes the assembly of the display device 10 and the control board 11 into the lower case portion 60a.

[0033] (effect) According to the embodiment described above, the following effects are achieved. (1) The head-up display device 100 includes a display device 10 that emits display light L and a concave mirror 30 that reflects the display light L, and projects the display light L onto a windshield 201, which is an example of a projection target. The head-up display device 100 includes a case 60 that supports the display device 10 and the concave mirror 30, a control board 11 that is an example of a circuit board and is installed on the outer surface of the case 60 and has a control unit 11a that controls the display device 10, a cable 13 that is an example of a wiring unit that electrically connects the control board 11 and the display device 10, a metal cover 61 that covers the control board 11, and a resin cover 62 that covers at least the cable 13. The metal cover 61 and the resin cover 62 at least partially overlap each other, and have lap portions 61c and 62c through which the cable 13 passes. According to this configuration, the metal cover 61 and the resin cover 62 are used in combination. Since the resin cover 62 has a high degree of freedom in shape, the wrap portion 62c of the resin cover 62 can be overlapped with the wrap portion 61c of the metal cover 61 without any gaps, improving the airtightness of the cover and suppressing radiation noise. Furthermore, since the control board 11, which is prone to radiating noise, is covered by the metal cover 61, EMC (Electromagnetic Compatibility) performance can be improved. Therefore, noise countermeasures can be implemented. Furthermore, the use of the resin cover 62 can reduce the weight of the head-up display device 100. Furthermore, flexible design is possible, such as the metal cover 61 being specially designed and common to different models of head-up display devices, and the resin cover 62 being changed for each model of head-up display device.

[0034] (2) The metal cover 61 includes an outer frame portion 61d that is a flat frame with a portion interrupted on the outer periphery of the metal cover 61, and a recessed portion 61a that is surrounded by the outer frame portion 61d and is recessed toward the control board 11. The metal wrap portion 61c of the metal cover 61 is located in the portion of the outer frame portion 61d and bulges out so as to cover the end of the cable 13 on the control board 11 side from the width direction (short direction) of the cable 13. The resin wrap portion 62c of the resin cover 62 is formed so as to cover the metal wrap portion 61c from the opposite side (below) of the cable 13. According to this configuration, the head-up display device 100 can be reliably sealed by overlapping the resin wrap portion 62c tightly with the metal wrap portion 61c at the portion where the cable 13 passes, which cannot be reliably sealed with only the metal cover 61. Therefore, the EMC performance can be improved.

[0035] (3) The resin cover 62 has shielding properties and is made of a resin that has no surface conductivity. With this configuration, the lack of surface conductivity of resin cover 62 reduces EMI (Electro Magnetic Interference) noise applied to cable 13 and cord 14 compared to a metal cover. For example, from the perspective of static electricity, if there is surface conductivity and the cable touches a cover with surface conductivity during assembly, static electricity applied to the metal casing or the cover with surface conductivity is applied directly to the cable, reducing resistance to EMI noise caused by static electricity. On the other hand, if there is no surface conductivity, even if cable 13 and cord 14 are in contact with resin cover 62, there is no conductivity between cable 13 and cord 14, so direct application of noise to cable 13 and cord 14 can be prevented. Furthermore, by covering the cable 13 with the wrap portions 61c and 62c, each of which has a shielding property, external noise is prevented from entering the cable 13 from the vicinity of the wrap portions 61c and 62c.

[0036] The present disclosure is not limited to the above-described embodiments and drawings. Modifications (including deletion of components) may be made as appropriate within the scope of the present disclosure. An example of such a modification is described below.

[0037] (Variation) In the above embodiment, the resin cover 62 covers the lower surface side of the display device 10 attached to the lower case part 60a, but it is sufficient if it covers at least the cable 13. For example, the resin cover 62 may cover the cable 13, and another metal or resin cover may cover the display device 10 other than the cable 13. In the above embodiment, the metal cover 61 and the resin cover 62 are configured as separate bodies, but they may be formed as one body. The metal cover 61 and the resin cover 62 may be configured as adjacent and integrally combined, or a through hole may be formed in the metal cover 61 and the resin cover 62 may be fitted in to fill this through hole. In the above embodiment, the wrap portions 61c, 62c are formed on parts of the metal cover 61 and the resin cover 62 in the X direction, but they may be formed on the entire areas of the metal cover 61 and the resin cover 62 in the X direction. Also, the wrap portions 61c, 62c may be formed on the corners of the metal cover 61 and the resin cover 62, respectively. In the above embodiment, the resin wrap portion 62c is formed to cover the metal wrap portion 61c, but the opposite may be true: the metal wrap portion 61c may be formed to cover the resin wrap portion 62c. Also, the resin wrap portion 62c may be formed with a groove into which the metal wrap portion 61c can be inserted. In the above embodiment, the shape of the wrap portions 61c, 62c can be changed as appropriate. For example, the wrap portions 61c, 62c may be shaped to cover the cable 13 from both the top and bottom. In the above embodiment, the resin cover 62 is formed to have shielding properties over the entire area, but the resin cover 62 may be configured by combining parts that have shielding properties and parts that do not have shielding properties. The positional relationship between the metal cover 61 and the resin cover 62 can be changed as appropriate. For example, the metal cover 61 and the resin cover 62 may be arranged side by side in the X direction. At least one of the metal cover 61 and the resin cover 62 may be attached to the side surface of the lower case portion 60a. In this case, the cover may be bent so as to fit along the side surface and bottom surface of the lower case portion 60a. In the above embodiment, the head-up display device 100 projects the display light L onto the windshield 201, which is an example of a projection target member, but the projection target member is not limited to this and may be a dedicated combiner. In the above embodiment, the head-up display device 100 may include a folding mirror that reflects the display light L from the display device 10 toward the concave mirror 30. In the above embodiment, the head-up display device 100 may include a mirror drive mechanism that rotates the concave mirror 30 around a rotation axis along the vehicle width direction. [Explanation of symbols]

[0038] 1...Viewer 10...display device, 13, 15...cable, 13a...end portion, 14...cord line 11...control board, 11a...control unit 30...Concave mirror 60...case, 60a...lower case portion, 60b...upper case portion, 60c...board accommodating portion, 60w...window portion 61...metal cover, 61a...recessed portion, 61a1...ceiling wall portion, 61a2...side wall portion, 61b, 62b...screw fastening portion, 61c...metal lap portion, 61c1...ceiling wall portion, 61c2, 61c3...side wall portion, 61d...outer frame portion 62...resin cover, 62c...resin wrap portion, 62d...ceiling wall portion, 62d1...recess, 62e...side wall portion, 62r...rib, 62c1...ceiling wall portion, 62c2, 62c3...side wall portion 70... Illumination device, 74... Illumination case, 75... Light source board, 75a... Light source, 79... Heat sink 80...display unit, 83...relay board, 84...display panel, 85...display case 100...Head-up display device 200...Vehicle, 201...Windshield A...Overlap area, B...Vis, C...Lap area, L...Display light, V...Virtual image, IL...Illumination light

Claims

1. A head-up display device comprising: a display device that emits display light; and a mirror that reflects the display light, and projects the display light onto a projection member, a case supporting the display device and the mirror; a circuit board having a control unit that is installed on an outer surface of the case and controls the display device; a wiring portion that electrically connects the circuit board and the display device; a metal cover attached to the case so as to cover the circuit board; a resin cover attached to the case so as to cover at least the wiring portion, The metal cover and the resin cover have overlapping portions at least partially overlapping with each other. Head-up display device.

2. The metal cover is an outer frame portion having a flat frame shape with a portion interrupted on the outer periphery side of the metal cover; a recessed portion that is surrounded by the outer frame portion and is recessed relative to the circuit board, the lap portion of the metal cover is located at the portion of the outer frame portion and bulges out to cover the end of the wiring portion on the circuit board side; The wrap portion of the resin cover is formed to cover the wrap portion of the metal cover from the opposite side of the wiring portion. The head-up display device according to claim 1 .

3. The resin cover is formed of a resin that has shielding properties and has no surface conductivity. The head-up display device according to claim 1 or 2.

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