Light guide body illumination device

Abstract

To enable only a light guide body to be easily replaced and prevent moisture and dust from entering between a light source and the light guide body.SOLUTION: A light guide body illumination device 10 is used, for example, in a head-up display that projects light onto a screen portion disposed at a front portion of a vehicle, and comprises: a first housing 20; a light guide body 40 which guides light from the first housing 20 side; a transparent elastic body 34; and a fastening member (screw) 13 for fixing the light guide body. The transparent elastic body 34 is made of an elastic body such as transparent rubber and allows light from a light source 31 to pass therethrough. The transparent elastic body 34 is disposed inside a partition portion 22 of the housing 20, is compressed by fixing of the fastening member (screw) 13 of the light guide body 40 and brings a window portion 33, the transparent elastic body 34, and the light guide body 40 into close contact with each other. By sandwiching the transparent elastic body 34 between the window portion 33 and the light guide body 40, moisture and dust are prevented from entering between the window portion 33 and the light guide body 40.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a light guide lighting device that projects light onto a screen portion disposed at the front of a vehicle or the like. [Background technology]

[0002] Some vehicles are equipped with a light guide lighting device (head-up display) that projects light onto a screen such as the windshield to provide the driver with necessary information. For example, the light guide lighting device is installed on the dashboard of the vehicle and projects light onto the windshield. Patent Document 1 discloses a conventional light guide lighting device.

[0003] The light guide lighting device shown in Patent Document 1 is composed of a plate-shaped combiner (light guide) and an edge light source, and guides the illumination light that enters the inside of the combiner to make the light image visible.

[0004] However, the combiner described in Patent Document 1 is fixed inside the housing, and if the combiner becomes dirty due to scratches or deterioration, or if it is damaged by external impact, it is not possible to replace just the combiner.

[0005] Furthermore, if a replacement structure is provided, when water or debris gets between the light source and the combiner, the water can cause refraction or the debris can cast a shadow on the light path, affecting the appearance of the light emitted and potentially preventing the driver from being properly notified. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2016 / 042598 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a technology that allows for easy replacement of only the light guide and prevents moisture and dust from entering between the light source and the light guide. [Means for solving the problem]

[0008] A light guide lighting device according to a first aspect includes a housing having an opening formed therein, a substrate provided inside the housing, a light source provided on the substrate for irradiating light onto the opening, a transparent window provided in the opening through which light from the light source passes, and a light guide provided on the outside of the housing at a position covering the window, rising in a plate shape outward from the housing, and guiding light, The light guide is fixed to the housing with a transparent elastic body sandwiched between the window and the end face of the light guide.

[0009] In a second aspect of the light guide lighting device that can be dependent on the first aspect, the housing is provided with a partition-shaped partition portion that is formed to surround the window portion and the light incident surface of the light guide.

[0010] In the light guide illumination device according to a third aspect which may be dependent on the second aspect, the partition has a slit formed by cutting out a part of the partition.

[0011] In a fourth aspect according to any one of the first to third aspects, the light guide illumination device further includes a fixing portion that is fixed to the housing on a base end side of a plate-shaped light emitting surface portion of the light guide, A weak portion that has low strength and breaks when subjected to an external impact is provided between the fixing portion and the plate-shaped light emitting surface portion. [Effects of the Invention]

[0012] According to the first aspect, a transparent elastic body is provided on the upper surface of the window of the housing, which prevents water or dust from entering between the housing and the light guide when the light guide is replaced, thereby preventing changes in the light path or scratches on the window caused by such external factors from affecting the appearance of the light when it is turned on.

[0013] According to the second aspect, a boundary surface is generated where the window portion of the housing, the transparent elastic body, and the light-receiving surface of the light guide meet. When the light is turned on, there is a possibility that light emission different from that at the light-emitting surface of the light guide will occur at the boundary surface. However, the partition portion formed in a partition shape to surround the light-receiving surface of the light guide prevents the driver from noticing the light emission at the boundary surface and can correctly notify the driver.

[0014] According to the third aspect, water that has entered the inside of the partition can be discharged through the slit portion of the partition, thereby reducing the impact on the light emitted by the light guide and allowing the driver to be properly notified.

[0015] In the prior art, when the light guide is subjected to an external impact and broken, depending on how the light guide is broken, sharp edges may remain, which is undesirable for the driver and the surrounding environment. In this regard, according to the fourth aspect, when an impact is applied to the light guide, the light guide breaks from a weak part of the structure with reduced strength, thereby preventing the occurrence of sharp edges and making it easy to replace only the light guide. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a partial cross-sectional front view of a light guide illumination device according to an embodiment of the present invention. [Figure 2] 2 is a side cross-sectional view of another embodiment of the light guide illumination device shown in FIG. 1. FIG. [Figure 3] 2 is a side cross-sectional view of the light guide illumination device shown in FIG. 1. FIG. [Figure 4] FIG. 2 is a plan view of the light guide illumination device shown in FIG. [Figure 5] 10A and 10B are diagrams illustrating the operation of a light guide lighting device according to a comparative example. [Figure 6] 1 is a diagram illustrating the operation of a light guide lighting device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings. In the description, the terms "left" and "right" refer to the left and right of the vehicle occupants, and the terms "front" and "rear" refer to the front and rear of the vehicle. <Example>

[0018] Please refer to Figures 1, 3 and 4. The light guide lighting device 10 is used in a head-up display that projects light onto a screen portion disposed at the front of a vehicle or the like, for example.

[0019] Light guide lighting device 10 comprises first housing 20, light guide 40 that guides light from first housing 20, transparent elastic body 34, and fastening member (screw) 13 for fixing the light guide.

[0020] In detail, the light guide lighting device 10 comprises an upper first housing 20 having an opening 24 formed therein, a lower second housing 21 that is fitted into the first housing 20, a substrate 30 provided inside the housings 20 and 21, a light source (LED lighting) 31 provided on the substrate 30 that irradiates the opening 24, and a heat sink 32 provided on the housings 20 and 21 that dissipates heat from the substrate 30.

[0021] The substrate 30 is fastened to the heat sink 32 by fastening members (screws) 11, and the heat sink 32 is fastened to the lower part of the housing 20 from below by fastening members (screws) 12.

[0022] The light guide lighting device 10 also includes a transparent window portion 33 that is provided in the opening 24 and transmits light from the light source 31, and a light guide 40 that is provided on the outside of the housing 21 at a position that covers the window portion 33, rises in a plate shape outside the housing 21, and guides light.

[0023] The light guide 40 is fixed to the upper surface of the housing 20 by fastening members (screws) 13 with a transparent elastic body 34 that is transparent and elastic and is sandwiched between the window portion 33 and the lower end face of the light guide 40.

[0024] The light guide 40 is provided with a fixing portion 43 that is fixed to the housing 20 on the base end side of the plate-shaped light-emitting surface portion 42. A fragile portion 44 that has low strength and is likely to break when subjected to an external impact is provided between the fixing portion 43 and the plate-shaped light-emitting surface portion 42.

[0025] The opening 24 is formed in a cylindrical shape extending from the rear surface side of the housing 20 to the light source 31 side, blocks light from the light source 31 so that it does not leak to the outside, and allows the light to pass only through the window portion 33 side.

[0026] The housing 20 is provided with a partition 22 in the shape of a partition formed to surround the window 33 and the light entrance surface 41 of the light guide 40. The partition 22 has a slit 23 cut out in part.

[0027] In summary, it can be rephrased as follows: The housings 20 and 21 are made of resin or metal, and have an LED lighting unit mounted therein, which is made up of a light source (LED) 31 and a substrate 30. The number and color of the LEDs serving as the light source 31 may be changed according to the size and application of the light guide 40.

[0028] Within the top surface of the housing 20, a window 330 made of resin or glass is provided above the light source (LED) 31, allowing light from the light source 31 to pass through. A partition 22 is provided so as to surround the periphery of the window 33 of the housing 20, and a drainage slit 23 is provided on the far side as seen from the driver 50 of the vehicle.

[0029] The light guide 40 is made of a transparent resin and is fixed to the housing 20. A weak portion 44, which serves as a structure that reduces strength, is provided between the fixing portion 43 and the light emitting surface portion 42 of the light guide 40, so that the weak portion 44 is more likely to break when an external impact is applied.

[0030] The transparent elastic body 34 is made of an elastic body such as transparent rubber, and allows light from the light source 31 to pass through. The transparent elastic body 34 is placed inside the partition part 22 of the housing 20, and is compressed by fastening members (screws) 13 of the light guide 40, thereby tightly adhering the window part 33, the transparent elastic body 34, and the light guide 40. The transparent elastic body 34 is sandwiched between the window part 33 and the light guide 40, thereby preventing moisture and dust from entering between the window part 33 and the light guide 40.

[0031] Next, a partial modification of the light guide illumination device 10 will be described. Please refer to Figure 2. (A) shows the normal state of the light guide lighting device 10 without the partition 22. A boundary surface B1 is formed between the window 33 and the transparent elastic body 34, and a boundary surface B2 is formed between the transparent elastic body 34 and the light guide 40. The same reference numerals will be used for the same components as those of the light guide lighting device 10 with the partition 22, and detailed explanations will be omitted.

[0032] (B) shows the light guide lighting device 10 in a turned-on state without the partition portion 22. When light is irradiated from the light source (LED) 31, light is emitted from the boundary surface B1, the boundary surface B2, and the light emitting surface portion 42. In addition to light emitted from the light emitting surface portion 42, light is also emitted from the boundary surface B1 and the boundary surface B2, which may provide room for improving the accuracy of notification to the driver.

[0033] Next, the light guide lighting device 10 having the partition portion 22 will be described. 3, (A) shows the normal state of the light guide lighting device 10 with the partition 22. A boundary surface B1 is formed between the window 33 and the transparent elastic body 34, and a boundary surface B2 is formed between the transparent elastic body 34 and the light guide 40.

[0034] (B) shows the state of the light guide lighting device 10 with the partition 22 when it is turned on. When light is irradiated from the light source (LED) 31, light is emitted from the boundary surface B1, the boundary surface B2, and the light emitting surface 42. In addition to light emitted from the light emitting surface 42, light is also emitted from the boundary surface B1 and the boundary surface B2, but the partition 22 blocks the light emitted from the boundary surface B1 and the boundary surface B2, preventing it from leaking outward. This improves the accuracy of the notification to the driver.

[0035] Next, the function of the slits provided in the partition 22 will be described. See Fig. 4. The presence of slit portion 23 allows water that has entered inside partition portion 22 to be expelled through slit portion 23. This reduces the effect on the light emitted by light guide 40, and allows driver 50 to be properly notified.

[0036] Next, the operation of the light guide lighting device 100 according to the comparative example will be described. 5, (A) shows a normal state of a light guide lighting device 100 according to a comparative example, in which a light guide 102 is provided in a housing 101, and the light guide 102 is fixed to a fixing portion 103 with a fastening member 104.

[0037] (B) shows the state of the light guide of the light guide lighting device 100 according to the comparative example when the light guide is damaged. When the light guide 102 receives an external impact, the light guide 102 is firmly fixed to the fixing portion 103, so it is unlikely to be damaged at the base end, but damage occurs from the middle portion of the light guide 102 in the vertical direction, which may result in sharp corners 102a at the damaged portion, which is undesirable.

[0038] Next, the operation of the light guide lighting device 10 according to the embodiment will be described. 6, (A) shows a normal state of the light guide lighting device 10 according to the embodiment, in which the light guide 40 is provided in the housing 20. A fixing portion 43 is provided on the main body of the light guide 40 via a fragile portion 44, and is fixed to the housing 20 with a fastening member 13.

[0039] 1B shows the state of the light guide of the light guide lighting device 10 according to the embodiment when the light guide is damaged. When the light guide 40 receives an external impact, the weak portion 44 is weaker than the other portions of the light guide 40, so the light guide 40 breaks from the weak portion 44. Therefore, no sharp corners are formed on the damaged light guide 40. Furthermore, when repairing after damage, the fastening members (screws) 13 of the fixing portions 43 of the light guide 40 can be removed, and only the light guide 40 can be removed, and a new light guide 40 can be attached. In this way, replacement can be performed by removing and attaching only the light guide 40, improving workability.

[0040] Next, the effects of the light guide lighting device 10 of the embodiment described above will be described. According to the light guide lighting device 10 of the embodiment, the transparent elastic body 34 is provided on the upper surface of the window portion 33 of the housing 20, which prevents water and dust from entering between the housing 20 and the light guide 40 when the light guide 40 is replaced. This prevents the appearance of the light from being affected by changes in the light path or scratches on the window portion due to such external factors.

[0041] Furthermore, boundaries B1 and B2 are generated where the window portion 33 of the housing 20, the transparent elastic body 34, and the light entrance surface 41 of the light guide 40 meet. When the light is turned on, there is a possibility that light emission different from the light emission at the light-emitting surface portion 42 of the light guide 40 will be generated at the boundaries B1 and B2. However, the partition portion 22, which is formed in a partition shape so as to surround the light entrance surface 41 of the light guide 40, prevents the driver from noticing the light emission at the boundaries B1 and B2 and can correctly notify the driver.

[0042] Furthermore, in the partition section 22, water that has entered the inside of the partition section 22 can be discharged through the slit section 23, reducing the impact on the light emission of the light guide 40 and allowing the driver 50 to be properly notified.

[0043] Furthermore, when the light guide 40 is subjected to an impact, it breaks from the weak portion 44 having a structure with reduced strength, thereby preventing the occurrence of sharp shapes and allowing for easy replacement of the light guide 40 alone.

[0044] Although the light guide lighting device 10 according to the present invention has been described as being used in a head-up display of a vehicle, it can also be applied to lighting devices used in general machinery and equipment, and is not limited to these types. In other words, the present invention is not limited to the examples, as long as the functions and effects of the present invention are achieved. [Industrial Applicability]

[0045] The light guide illumination device 10 of the present invention is suitable for use in a head-up display. [Explanation of symbols]

[0046] 10…Light guide lighting device 13... Fastening member (screw) 20...First housing (housing, case) 21...Second housing (housing, case) 22...Partition 23...Slit section 24...Opening 30...Substrate 31…Light source (LED) 33...Window section 34...Transparent elastic body 40...Light guide 41...Light incident surface 42...Light-emitting surface 43…Fixed part 44...Weak part B1: Boundary between the window and the transparent elastic body B2: Boundary between transparent elastic body and light guide body L1: Emission from boundary surface B1 L2: Emission from boundary surface B2 L3: Light emitted from the light-emitting surface

Claims

1. a light source provided on the substrate and irradiating the opening with light; a transparent window provided in the opening and transmitting light from the light source; and a light guide provided on the outside of the housing at a position covering the window, rising in a plate shape outward from the housing, and guiding light, The light guide is fixed to the housing with a transparent elastic body sandwiched between the window portion and the end face of the light guide.

2. 2. The light guide illumination device according to claim 1, wherein the housing is provided with a partition-shaped partition portion formed to surround the window portion and the light incident surface of the light guide.

3. 3. The light guide illumination device according to claim 2, wherein the partition has a slit formed by cutting out a part of the partition.

4. the light guide has a fixing portion fixed to the housing on a base end side of a plate-shaped light emitting surface portion, 2. The light guide lighting device according to claim 1, wherein a weak portion having low strength and capable of being broken by an external impact is provided between the fixing portion and the plate-shaped light emitting surface portion.

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