Road surface projection device

Abstract

To provide a road surface projection device with excellent cooling capabilities. [Solution] The road surface projection device (10) includes a mirror housing (20) made of a thermally conductive material, a projector (30) provided inside the mirror housing (20) for projecting information onto the vehicle body and the road surface, a heat sink (15) embedded in the mirror housing (20) and connected to the projector (30) for cooling the projector (30), and a mirror body (16), which is a mirror, provided at the rear of the mirror housing (20). The mirror housing (20) has a heat sink hole (22a) which is a hole opened to allow airflow to be taken in while driving.

Description

Technical Field

[0001] The present invention relates to a road surface projection device. Background Art

[0002] As a conventional technique for projecting an image onto a road surface, there is a technique disclosed in Patent Document 1.

[0003] As disclosed in Patent Document 1, one example of a road surface projection device has a projector provided in a mirror housing of a side mirror, and the projector projects various types of information onto a road surface. Prior Art Documents Patent Documents

[0004] Patent Document 1 Japanese Unexamined Patent Publication No. 2024-156244 Summary of the Invention Problems to be Solved by the Invention

[0005] Projectors generally become hot during use, so heat countermeasures are required. In particular, for a projector provided in a door mirror, it is necessary to achieve cooling while avoiding an increase in size.

[0006] An object of the present invention is to provide a road surface projection device having an excellent cooling function. Means for Solving the Problems

[0007] The road surface projection device according to the first aspect comprises: a mirror housing made of a thermally conductive material; a projector provided inside the mirror housing and configured to project information onto a vehicle body or a road surface; a heat sink embedded in the mirror housing and connected to the projector to cool the projector; and a mirror body which is a mirror provided at a rear portion of the mirror housing, The mirror housing has a heat sink vent, which is a hole that is opened to allow airflow to be taken in while driving.

[0008] In a road surface projection device in a second embodiment which may be dependent on the first embodiment, the heat sink holes are shaped such that their cross-sectional area continuously decreases from the outer circumferential surface of the mirror housing toward the interior.

[0009] In a third embodiment of the road surface projection device that may be dependent on the first or second embodiment, the upper surface of the mirror housing is covered by a resin cover member.

[0010] In a fourth embodiment of the road surface projection device, which may be dependent on any of the first to third embodiments, the heat sink is fastened to the projector by metal screws.

[0011] In a fifth embodiment of the road surface projection device, which may be dependent on any of the first to fourth embodiments, the mirror body is provided with a gap between it and the mirror housing. [Effects of the Invention]

[0012] According to this disclosure, it is possible to provide a road surface projection device with excellent cooling capabilities. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view of a road surface projection device according to an embodiment. [Figure 2] This is a cross-sectional view taken along line 2-2 in Figure 1. [Figure 3] This is a cross-sectional view taken along line 3-3 in Figure 2. [Figure 4] Figure 2 is a perspective view illustrating the mounting of the heatsink to the projector. [Modes for carrying out the invention]

[0014] Embodiments of the present invention will be described below with reference to the attached drawings. In this description, left and right refer to the left and right relative to the vehicle occupants, and front and rear refer to the front and rear relative to the direction of travel of the vehicle. In the drawings, Fr indicates front, Rr indicates rear, Le indicates left from the occupants' perspective, Ri indicates right from the occupants' perspective, Up indicates up, and Dn indicates down.

[0015] <Examples> Refer to Figure 1. The road projection device 10 is installed on the front side of the vehicle and is integrated with the door mirror used for checking vehicles behind the vehicle. The road projection device 10 is a device for projecting information onto the vehicle body or the road surface. For example, the road projection device 10 can project the direction the vehicle is moving onto the road surface or project the opening of a door onto the vehicle body, thereby allowing pedestrians and other vehicles to recognize the movement of the vehicle.

[0016] Refer to Figures 2 and 3. The road surface projection device 10 includes a mirror support portion 11 extending outward from the vehicle body, an aluminum mirror housing 20 supported by the mirror support portion 11, a resin cover member 13 covering the upper surface of the mirror housing 20, a projector 30 provided inside the mirror housing 20 for projecting information onto the vehicle body and the road surface, a heat sink 15 embedded in the mirror housing 20 and connected to the projector 30 for cooling the projector 30, and a mirror body 16, which is a mirror, provided at the rear of the mirror housing 20.

[0017] The mirror housing 20 has an open rear surface and a hollow interior. The mirror housing 20 is, for example, a die-cast part and has a lower surface portion 21 with a lower opening 21a through which light projected from the projector 30 can pass; a front surface portion 22 extending upward from the front end of the lower surface portion 21; an upper surface portion 23 extending rearward from the upper end of the front surface portion 22; a left wall portion 24 rising from the left end of the lower surface portion 21; and a right wall portion 25 rising from the right end of the lower surface portion 21.

[0018] A plurality of heat sink holes 22a are formed in the front surface portion 22 so that traveling wind can be taken in. The heat sink holes 22a are configured such that the cross-sectional area continuously decreases from the front toward the rear, and the cross-sectional area of a portion facing the internal hollow portion is the smallest.

[0019] Note that the heat sink holes 22a may be formed in a portion other than the front surface portion 22, or may be formed in the front surface portion 22 and another portion, but in order to efficiently take traveling wind into the interior, the heat sink holes 22a are preferably formed at least in the front surface portion 22.

[0020] A groove-shaped heat sink housing portion 24a is formed in the left wall portion 24, and the heat sink 15 is embedded in this portion.

[0021] Note that the heat sink 15 may be cast into the mirror housing 20 by a method such as insert casting.

[0022] Further, depending on the shape of the projector 30, the heat sink 15 may be embedded in the right wall portion 25, or may be embedded in both the left wall portion 24 and the right wall portion 25.

[0023] The lid member 13 is a colored resin member, and reduces the area where direct sunlight hits the mirror housing 20.

[0024] For the projector 30, for example, a known ultra-short throw projector can be used. The projector 30 includes an imaging device 31 on which an image to be projected is formed, a projection unit 32 that projects the image formed by the imaging device 31, and a heat dissipation unit 33 connected to the imaging device 31 and / or the projection unit 32 for dissipating heat.

[0025] Refer to Figure 4. The heat sink 15 is fastened to the heat dissipation section 33 of the projector 30 by metal screws 18. A well-known heat pipe can be applied to the heat sink 15, which consists of a serpentine pipe-shaped component with a heat transfer medium sealed inside for heat exchange.

[0026] For example, the pipe portion of a heat pipe is made of materials such as copper, aluminum, or stainless steel, and the inside is filled with a working fluid such as pure water, ethanol, or naphthalene.

[0027] The mirror body 16 is supported by the mirror housing 20 so as to be displaceable up and down and left and right, and is provided with a gap between it and the mirror housing 20. Following vehicles, etc., are reflected on the rear surface of the mirror body 16.

[0028] The road surface projection device 10 described above is summarized below.

[0029] Firstly, the road surface projection device 10 includes a mirror housing 20 made of a heat-conductive material, a projector 30 provided inside the mirror housing 20 for projecting information onto the vehicle body and the road surface, a heat sink 15 embedded in the mirror housing 20 and connected to the projector 30 for cooling the projector 30, and a mirror body 16, which is a mirror, provided at the rear of the mirror housing 20. The mirror housing 20 has a heat sink hole portion 22a, which is a hole opened to allow airflow to be taken in while driving.

[0030] A heatsink 15 is embedded in the mirror housing 20, and the projector 30 is connected to this heatsink 15. Therefore, the heat transfer medium inside the heatsink 15, which becomes hot due to the projector 30, is cooled by the aluminum mirror housing 20. Since the mirror housing 20 is a part that receives airflow while the vehicle is in motion, it can efficiently cool the projector 30 via the heatsink 15.

[0031] Furthermore, the mirror housing 20 has heat sink holes 22a. By directly drawing in airflow from driving into the mirror housing 20 through the heat sink holes 22a, the projector 30 can be exposed to the airflow. This allows for efficient cooling of the projector 30. This provides a road surface projection device 10 with excellent cooling capabilities.

[0032] Secondly, assuming the first road surface projection device 10, the heat sink holes 22a are shaped so that the cross-sectional area continuously decreases from the outer circumferential surface of the mirror housing 20 toward the interior. In other words, by narrowing the airflow path toward the interior of the mirror housing 20, the airflow velocity can be increased. By directing the airflow at a high velocity toward the projector 30, the projector 30 can be cooled more reliably.

[0033] Thirdly, assuming the first or second road surface projection device 10, the upper surface of the mirror housing 20 is covered by a resin cover member 13. Generally, resin has a higher thermal conductivity and specific heat than aluminum. By providing the cover member 13, the temperature of the mirror housing 20 can be suppressed compared to when the sun directly shines on the mirror housing 20, and the projector 30 can be cooled efficiently.

[0034] Fourth, assuming any of the first to third road surface projection devices 10, the heat sink 15 is fastened to the projector 30 by metal screws 18. This allows the heat sink 15 to be fastened to the projector 30 with high strength, and also allows the heat from the projector 30 to be efficiently transferred to the heat sink 15.

[0035] Fifth, assuming any of the first to fourth road surface projection devices 10, the mirror body 16 is provided with a gap between it and the mirror housing 20. The air guided into the mirror housing 20 from the heat sink holes 22a flows around the outer circumference of the projector 30 and is discharged to the outside through the gap between the mirror housing 20 and the mirror body 16. The gap between the mirror housing 20 and the mirror body 16 allows for efficient discharge of airflow to the outside, and this also allows for efficient guidance of airflow into the mirror housing 20 from the heat sink holes 22a. This enables efficient cooling of the projector 30.

[0036] Although the road surface projection device 10 according to the present invention has been described using an example where it is installed on the right side of the vehicle body, it may also be installed on the left side of the vehicle body. Furthermore, it may be installed not only on one side of the vehicle body, but on both sides.

[0037] Furthermore, in the following embodiments, the mirror housing 20 is made of aluminum, but it is also possible to change it to other materials (thermally conductive materials) that have a higher thermal conductivity than typical materials such as ABS resin (approximately 0.17 W / m / K) or PP (polypropylene) (approximately 0.22 W / m / K). Specifically, the mirror housing 20 may also be made of steel (approximately 50 W / m / K), a composite material of steel and aluminum, or a resin containing heat dissipation fillers (PA (polyamide) type: approximately 1-5 W / m / K, PBT (polybutylene terephthalate) type: approximately 1-3 W / m / K, PPS (polyphenylene sulfide) type: approximately 2-7 W / m / K).

[0038] Insofar as the present invention achieves its functions and effects, the present invention is not limited to the examples provided. [Industrial applicability]

[0039] The road surface projection device of the present invention is suitable for use in the door mirrors of passenger cars. [Explanation of Symbols]

[0040] 10…Road surface projection device 13... Lid component 15… Heatsink 16…Mirror body 18... screw 20… Mirror housing 22a...Heat sink vents 30…Projector

Claims

1. The system comprises a mirror housing made of a thermally conductive material, a projector provided inside the mirror housing for projecting information onto the vehicle body or road surface, a heat sink embedded in the mirror housing and connected to the projector for cooling the projector, and a mirror body which is a mirror provided at the rear of the mirror housing. The aforementioned mirror housing has a heat sink vent portion, which is a hole opened to allow airflow during driving, and is a road surface projection device.

2. The road surface projection device according to claim 1, wherein the heat sink holes have a shape in which the cross-sectional area decreases continuously from the outer circumferential surface of the mirror housing toward the interior.

3. The road surface projection device according to claim 1, wherein the upper surface of the mirror housing is covered by a resin cover member.

4. The road surface projection device according to claim 1, wherein the heat sink is fastened to the projector by metal screws.

5. The road surface projection device according to claim 1, wherein the mirror body is provided with a gap between it and the mirror housing.

Images