Vehicle lamp unit

Abstract

A vehicle lamp unit is provided with: a first light source (20a); a second light source (20b) disposed adjacent to the first light source; a reflector (16) having a first reflective surface (17a) that reflects a portion of light (L1) emitted from the first light source toward the front of the lamp, a second reflective surface (17b) that reflects a portion of light (L2) emitted from the second light source toward the front of the lamp, and a main rear surface (17c) that faces the emission surface of the first light source (20a) and the emission surface of the second light source (20b); and a metal plate having a main shielding part (18f) for shielding light from the first light source (20a) toward the main back surface (17c) and light from the second light source (20b) toward the main back surface (17c).

Description

Technical Field

[0001] The invention relates to a vehicle lamp unit. Background Art

[0002] In the past, a vehicle lamp is known in which a plurality of LEDs forming a low beam light distribution pattern and a high beam light distribution pattern are mounted in an array on a circuit substrate. For example, a vehicle lamp is proposed, which comprises: a circuit substrate on which a plurality of LEDs arranged in two layers are mounted so that the light-emitting surfaces thereof face the front of the vehicle lamp; a reflector which is arranged in front of the circuit substrate and reflects a part of the light emitted from the LED to form a low beam light distribution pattern and a high beam light distribution pattern; and a projection lens which projects the light emitted from the LED to the front of the lamp (Patent Document 1).

[0003] In the vehicle lamp, the plurality of LEDs arranged in the left-right direction on the upper layer side of the upper and lower layers mainly emit light for forming a low beam light distribution pattern, and the plurality of LEDs arranged in the left-right direction on the lower layer side mainly emit light for forming a high beam light distribution pattern. In addition, the reflector is formed of a metal material such as aluminum with high thermal conductivity.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2022 / 009683 Summary of the invention

[0007] Technical problem that the invention aims to solve

[0008] However, the reflector of the above-mentioned vehicle lamp is a metal component, so there is a tendency that the component weight increases and the material cost also becomes high. Therefore, by forming the reflector with a resin material, it is possible to achieve lightness and low cost, but compared with a metal reflector, it is more susceptible to the heat of the light source.

[0009] The present invention has been made in view of such circumstances, and one of its exemplary objects is to provide a new technology for alleviating the influence of heat from a light source.

[0010] Technical solutions to the problem

[0011] In order to solve the above-mentioned problems, a vehicle lighting unit of one embodiment of the present invention comprises: a first light source; a second light source, which is arranged adjacent to the first light source; a reflector, the reflector having: a first reflecting surface, which reflects a portion of the light emitted from the first light source toward the front of the lamp; a second reflecting surface, which reflects a portion of the light emitted from the second light source toward the front of the lamp; and a main back surface, which is opposite to the emission surface of the first light source and the emission surface of the second light source; and a metal plate, the metal plate having a main shielding portion for shielding the light from the first light source toward the main back surface and the light from the second light source toward the main back surface.

[0012] According to this method, the metal plate can be used to block the light from the first light source and the second light source toward the main back surface of the reflector, so that the temperature rise of the reflector can be suppressed. Therefore, the reflector is not made of expensive and heavy materials such as metal materials or ceramic materials that are heat-resistant materials, but can be made of cheap and light materials such as resin.

[0013] Effects of the Invention

[0014] According to the present invention, it is possible to alleviate the influence of heat from the light source on the reflector. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a side view showing a schematic structure of the vehicle lamp according to the present embodiment.

[0016] Figure 2 It is a perspective view of the main part of the vehicle lamp unit according to the present embodiment.

[0017] Figure 3 yes Figure 2 An exploded perspective view of a vehicle lamp unit is shown.

[0018] Figure 4 This is a schematic diagram of the area between the reflector and the circuit board viewed from the side of the lamp.

[0019] Figure 5 It is a schematic diagram showing the positional relationship of the protector relative to the reflector and each light source.

[0020] Figure 6 This is an exploded perspective view for explaining the assembly positions of the reflector, protector, and heat sink.

[0021] Figure 7 It is a rear perspective view showing a state where the protector is assembled to the reflector.

[0022] Figure 8 It is a schematic diagram for explaining the positioning of a reflector, a protector, and a heat sink. DETAILED DESCRIPTION

[0023] Hereinafter, the present invention will be described with reference to the accompanying drawings based on preferred embodiments. The same or equivalent components, parts, and processes shown in the respective drawings are marked with the same reference numerals, and repeated descriptions are appropriately omitted. In addition, the embodiments are merely examples and do not limit the invention, and all features and combinations thereof described in the embodiments are not necessarily the essence of the invention.

[0024] Figure 1 It is a side view showing a schematic structure of the vehicle lamp according to the present embodiment. Figure 2 It is a perspective view of the main part of the vehicle lamp unit according to the present embodiment. Figure 3 yes Figure 2 An exploded perspective view of a vehicle lamp unit is shown. Figure 2 , Figure 3 The illustrated vehicle lamp unit 10 is a vehicle headlamp provided at the front portion of a vehicle, and is configured to be able to form either a light distribution pattern for a low beam or a light distribution pattern for a high beam.

[0025] The vehicle lamp 100 includes a lamp body 2, an outer lens 4 covering an opening of the lamp body 2, a vehicle lamp unit 10 disposed in a lamp chamber 6 surrounded by the lamp body 2 and the outer lens 4, and an alignment mechanism 8 for holding the vehicle lamp unit 10 so that it can be aligned. The vehicle lamp unit 10 includes a projection lens 12, a lens holder 14, a reflector 16, a protector 18, a circuit board 20, a heat sink 22, and a fan 24.

[0026] The lens holder 14 has a substantially cylindrical lens holding portion 14a and three legs 14b protruding from the lens holding portion 14a toward the rear of the vehicle. The projection lens 12 is a transparent component, and is integrally formed with a lens main body 12a for controlling the optical path of light emitted from a light source and a flange-shaped mounted portion 12b protruding outward from the outer periphery of the lens main body 12a. The projection lens 12 is held in the lens holder 14 by aligning the mounted portion 12b of the projection lens 12 with the lens holding portion 14a of the lens holder 14 and fixing them with screws 26. The projection lens 12 is manufactured by injection molding using a resin material having high transparency and high heat resistance, such as acrylic or polycarbonate.

[0027] In order to reduce costs and reduce weight, the reflector 16 of this embodiment is made of a resin material. The reflector 16 has: a horizontally long base surface 16a, which faces the front-back direction; a side reflector 16c, which is arranged to protrude forward from the left and right sides of an opening 16b formed in the center of the reflector 16; an upper reflector 16d, in which the inner surface of the beam-shaped portion on the upper side of the opening 16b serves as a reflecting surface; and a light shielding cover 16e, which protrudes forward from the lower edge of the opening 16b.

[0028] The protector 18 is a member formed by bending a plate-like metal material into a predetermined shape, for example, and is disposed between the reflector 16 and the circuit board 20. The protector 18 includes a rectangular shielding portion 18c having two openings 18a and 18b, and a circuit protection portion 18d protruding forward in a crank shape from the lower portion of the shielding portion 18c. The circuit protection portion 18d prevents the sunlight that has entered from the outside through the projection lens 12 and has been concentrated from irradiating the driving circuit of the light source described later.

[0029] The circuit board 20 has: a first light source 20a, in which a plurality of light emitting elements 21a for forming a low beam light distribution pattern are arranged in a horizontal row; a second light source 20b, in which a plurality of light emitting elements 21b for forming a high beam light distribution pattern are arranged in a horizontal row; and a drive circuit 20c, which drives each light emitting element. The second light source 20b is arranged adjacent to the first light source 20a. In addition, the first light source 20a is located on the upper layer side, and the second light source 20b is located on the lower layer side. The drive circuit 20c is a circuit formed by combining passive elements such as capacitors and coils, active elements such as transistors and diodes, IC chips, memories, etc., and is mounted on an area of ​​the circuit board 20 that is lower than the area where the light sources 20a and 20b are mounted.

[0030] The light emitted from the first light source 20a passes through the opening 18a of the protector 18 and the opening 16b of the reflector 16. At this time, part of the light is reflected by the reflection surfaces of the side reflection part 16c, the upper reflector 16d and the hood part 16e, and is irradiated toward the projection lens 12 in the state of light distribution control. The projection lens 12 projects the light directly reaching from the first light source 20a and the light after light distribution control by each reflection surface to the front of the vehicle as a desired light distribution pattern. As a result, on the screen in front of the vehicle, the area below the horizontal line is mainly illuminated with the light of the low beam light distribution pattern.

[0031] Similarly, the light emitted from the second light source 20b passes through the opening 18b of the protector 18 and the portion below the shading cover 16e of the reflector 16. At this time, a portion of the light is reflected by the reflective surface on the lower side of the shading cover 16e and irradiated toward the projection lens 12 in a state of light distribution control. The projection lens 12 projects the light directly arriving from the second light source 20b and the light after light distribution control by each reflective surface to the front of the vehicle as a desired light distribution pattern. As a result, on the screen in front of the vehicle, the area above the horizontal line is mainly illuminated with the light of the high beam light distribution pattern. In this way, the projection lens 12 projects the light distribution pattern to the front of the lamp using the light emitted from at least one of the first light source 20a and the second light source 20b.

[0032] When the above-mentioned light sources are driven, heat is generated from the components and wirings constituting the light sources and the driving circuit 20c. A portion of the heat generated from the light sources 20a, 20b, etc. is transferred to the heat sink 22, and is released to the outside from various parts of the heat sink 22, especially the fins 22a. At this time, the cooling wind generated by the rotation of the cooling fan 24 flows along the fins 22a, thereby improving the heat dissipation. In addition, the lens holder 14 is fixed to the heat sink 22 by screws 28.

[0033] Next, the positional relationship between the reflector 16 and each light source will be described. Figure 4 This is a schematic diagram of the area between the reflector and the circuit board viewed from the side of the lamp. Figure 4 As shown, in the vehicle lamp unit 10 of the present embodiment, the reflector 16 and each light source 20a, 20b are very close. In particular, the shading cover 16e as a part of the reflector 16 is close to the emission surface (light emitting surface) of the upper light emitting element 21a and the emission surface (light emitting surface) of the lower light emitting element 21b.

[0034] The light shielding cover 16e includes: a first reflecting surface 17a for reflecting a part of the light L1 emitted from the first light source 20a toward the front of the lamp, a second reflecting surface 17b for reflecting a part of the light L2 emitted from the second light source 20b toward the front of the lamp, and a main back surface 17c opposite to the emission surface of the light emitting element 21a and the emission surface of the light emitting element 21b. Therefore, in the present embodiment, a protector 18 is arranged between the circuit substrate 20 and the reflector 16, and the protector 18 includes a main shielding portion 18f, and the shielding portion 18f shields the light L1' from the light emitting element 21a toward the main back surface 17c of the reflector 16 and the light L2' from the light emitting element 21b toward the main back surface 17c.

[0035] Therefore, the protector 18 can block the light from the first light source 20a and the second light source 20b toward the main back surface 17c of the reflector 16, so that the temperature rise of the reflector 16 can be suppressed. Therefore, the reflector can be made of a cheap and light material such as resin instead of an expensive and heavy material such as a metal material or a ceramic material which is a heat-resistant material.

[0036] The reflector 16 of this embodiment further includes an upper reflector 16d having a third reflective surface 17d that is opposite to the first reflective surface 17a and reflects a portion of the light emitted from the first light source 20a toward the front of the lamp. Figure 2 , Figure 3Although not shown in the figure, the reflector 16 shown may further include a lower reflector 16g having a fourth reflecting surface 17g facing the second reflecting surface 17b and reflecting a part of the light emitted from the second light source 20b toward the front of the lamp.

[0037] The upper reflector 16d has an upper back surface 17h opposite to the emission surface of the first light source 20a. In addition, the lower reflector 16g has a lower back surface 17k opposite to the emission surface of the second light source 20b. Moreover, the protector 18 has: an upper shielding portion 18g that blocks light from the first light source 20a toward the upper back surface 17h and a lower shielding portion 18h that blocks light from the second light source 20b toward the lower back surface 17k. Thus, the protector 18 can be used to block the light from the first light source 20a toward the upper back surface 17h of the reflector 16 and the light from the second light source 20b toward the lower back surface 17k of the reflector 16, so that the temperature rise of the reflector 16 can be suppressed.

[0038] The shading hood portion 16e forms a light-dark cutoff line of the light distribution pattern at the front end of the first reflecting surface 17a and the second reflecting surface 17b. The thickness D1 of the front end of the shading hood portion 16e is less than 0.2 mm, and the shading hood portion 16e is formed by a resin using a liquid crystal polymer. For liquid crystal polymer, even if the molded product is thin-walled, it shows good fluidity, so it is preferred when a component such as the shading hood portion 16e of the present embodiment is manufactured by injection molding. In this way, by forming the reflector 16 with a resin using a liquid crystal polymer, the reflector 16 having the shading hood portion 16e with a thickness of less than 0.2 mm can be formed using a mold, and the manufacturing cost of the reflector 16 can be reduced.

[0039] The protector 18 of the present embodiment further includes a circuit protection portion 18 k extending from the lower shielding portion 18 h toward the lower side of the lamp so as to be located between the drive circuit 20 c and the projection lens 12 .

[0040] Thus, when sunlight S enters from the outside through the projection lens 12 , the lower shielding portion 18 h can suppress the drive circuit 20 c located in a place in the lamp where light is easily concentrated from being damaged by heat.

[0041] Figure 5: is a schematic diagram showing the positional relationship of the protector relative to the reflector and each light source. The thickness D2 of the metal plate of the protector 18 of the present embodiment can be 0.2mm~0.6mm. Therefore, even if the protector 18 is arranged between each light source 20a, 20b and the reflector 16, each light source can be closer to the reflector 16. In addition, the distance D3 between the emission surface S1 of the light-emitting elements 21a, 21b and each back surface of the reflector 16 (the main back surface 17c, the upper back surface 17h, and the lower back surface 17k) can be 0.5mm~0.9mm. In other words, the shortest distance D4 between the emission surface S1 of the light-emitting element 21a and the main shielding part 18f is -0.1mm~0.7mm, and the shortest distance D5 between the emission surface S2 of the light-emitting element 21b and the main shielding part 18f is -0.1mm~0.7mm.

[0042] In addition, the distance between each back surface (main back surface 17c, upper back surface 17h, lower back surface 17k) of the reflector 16 and the protector 18 is preferably as narrow as possible, or they may be in contact. As a result, the proportion of light blocked by the protector 18 in the light emitted from the light source is reduced, so the proportion of light actually used for irradiation of the lamp in the light emitted from each light source is increased.

[0043] In addition, the reflector 16 can also be fixed to each shielding part. Here, fixing also includes the following cases: the reflector and each shielding part are integrated by laser welding or adhesive bonding, and the reflector and each shielding part are firmly integrated by insert molding of injection molding of a resin that becomes a reflector while a metal plate is placed in a mold. Thus, as a component for pre-positioning the reflector and the main shielding part with high precision, it can be used for the assembly of the vehicle lamp unit, so that the position alignment of the reflector and the protector is not required during assembly.

[0044] In addition, if the light from each light source toward the first reflecting surface 17a and the second reflecting surface 17b is blocked by the main shielding portion 18f, it may be impossible to form the desired light distribution pattern. Therefore, the width W1 of the main shielding portion 18f that blocks the emitted light is set to be about 0.04mm to 0.08mm smaller than the width W2 of the main back surface 17c. In addition, the main shielding portion 18f is set not to be exposed from the area between the two lines A1 and A2 that connect the emission surface S1 of each light source and the shortest distance of the main back surface 17c. Here, the emission surface S1 (S2) refers to the surface area where the light is actually emitted.

[0045] In other words, the opening width W3 between the main shielding portion 18f and the upper shielding portion 18g of the protector 18 is larger than the opening width W4 between the first reflecting surface 17a and the third reflecting surface 17d. In addition, the opening width W5 between the main shielding portion 18f and the lower shielding portion 18h of the protector 18 is larger than the opening width W6 between the second reflecting surface 17b and the fourth reflecting surface 17g.

[0046] By setting the sizes of the various parts of the protector 18 within the above conditions, the light from each light source toward the first reflecting surface 17a and the second reflecting surface 17b is no longer blocked by the main blocking portion 18f, thereby preventing vignetting from occurring in a desired light distribution pattern.

[0047] As described above, the positioning accuracy of the protector 18 relative to the reflector 16 is important. For example, if the position of the protector 18 relative to the reflector 16 deviates from the normal position, part of the light toward the first reflecting surface 17a and the second reflecting surface 17b may be blocked by the main shielding portion 18f. For example, when the reflector 16 and the protector 18 are positioned relative to the heat sink 22, the positioning accuracy of the protector 18 relative to the reflector 16 is affected by both the positioning error of the reflector 16 relative to the heat sink and the positioning error of the protector 18 relative to the heat sink.

[0048] Therefore, in the vehicle lamp unit 10 of the present embodiment, a structure is adopted in which the protector 18 is positioned relative to the reflector 16 . Figure 6 This is an exploded perspective view for explaining the assembly positions of the reflector, protector, and heat sink. Figure 7 It is a rear perspective view showing a state where the protector is assembled to the reflector. Figure 8 It is a schematic diagram for explaining the positioning of a reflector, a protector, and a heat sink.

[0049] like Figure 6 , Figure 7 As shown in FIG. 1 , the reflector 16 is provided with a positioning pin 16h protruding from the back side to the side opposite to the front of the vehicle. The protector 18 is formed with a positioning hole 18m for inserting the positioning pin 16h. The heat sink 22 is formed with a positioning hole 22b for inserting the positioning pin 16h. Then, the positioning pin 16h is inserted into the positioning hole 18m and the positioning hole 22b, and fixed to each other with a fastening member such as a screw. Thus, as shown in FIG. Figure 8 As shown, the protector 18 is directly positioned relative to the reflector 16 , so the positioning accuracy of the protector 18 relative to the reflector 16 is improved compared to the case where the reflector 16 and the protector 18 are positioned separately relative to the heat sink 22 .

[0050] In the vehicle lamp unit of the present invention, the thickness of the metal plate may be 0.2 mm to 0.6 mm. Thus, even if the metal plate is disposed between each light source and the reflector, each light source can be brought closer to the reflector to improve the utilization efficiency of the light emitted from the light source.

[0051] In the vehicle lamp unit of the present invention, the reflector may also include: an upper reflector having a third reflecting surface that is opposite to the first reflecting surface and reflects a portion of the light emitted from the first light source toward the front of the lamp; and a lower reflector having a fourth reflecting surface that is opposite to the second reflecting surface and reflects a portion of the light emitted from the second light source toward the front of the lamp. The upper reflector may also include an upper back surface that is opposite to the emission surface of the first light source. The lower reflector may also include a lower back surface that is opposite to the emission surface of the second light source. The metal plate may also include: an upper shielding portion that blocks light from the first light source toward the upper back surface; and a lower shielding portion that blocks light from the second light source toward the lower back surface. Thus, the metal plate can be used to block light from the first light source toward the upper back surface of the reflector and light from the second light source toward the lower back surface of the reflector, thereby suppressing the temperature rise of the reflector.

[0052] In the vehicle lamp unit of the present invention, the reflector may also have a shading hood portion, and the shading hood portion forms a light-dark cutoff line of the light distribution pattern at the front end portions of the first reflecting surface and the second reflecting surface. The shading hood portion may be a resin containing a liquid crystal polymer, and its thickness is 0.2 mm or less. By forming the reflector with a resin containing a liquid crystal polymer, a reflector having a shading hood portion with a thickness of 0.2 mm or less can be formed by molding, which can reduce the manufacturing cost of the reflector.

[0053] In the vehicle lamp unit of the present invention, it is also possible to further include: a projection lens for projecting a light distribution pattern in front of the lamp using light emitted from at least one of the first light source and the second light source; and a circuit substrate on which the first light source and the second light source are mounted. Alternatively, in the circuit substrate, a driving circuit for driving the first light source and the second light source is mounted below the first light source and the second light source, and the metal plate also has a circuit protection portion, which extends from the lower shielding portion to below the lamp in a manner located between the driving circuit and the projection lens. Thus, when sunlight enters from the outside through the projection lens, the circuit protection portion can be used to prevent the driving circuit located in a place in the lamp that is easy to focus light from being damaged by heat.

[0054] In the vehicle lamp unit of the present invention, the reflector may also be fixed to the main shielding portion. Here, fixing also includes the following cases: the reflector and each shielding portion are integrated by laser welding, adhesive bonding, and the two parts are firmly integrated by insert molding in which a resin that becomes the reflector is injection molded while a metal plate is placed on a mold. Thus, as a component for pre-positioning the reflector and the main shielding portion with high precision, it can be used in the assembly of the vehicle lamp unit.

[0055] In the vehicle lamp unit of the present invention, the reflector may be provided with a positioning pin protruding from the back side to the side opposite to the front of the vehicle. The metal plate may also be formed with a positioning hole for inserting the positioning pin. Thus, the metal plate is directly positioned relative to the reflector.

[0056] As a mode of the present invention, any combination of the above-mentioned components and modes in which the expression of the present invention is converted between manufacturing methods, lamps, lighting devices, light-emitting modules, light sources, etc. are also effective.

[0057] The present invention has been described above with reference to the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, and the structure formed by appropriately combining the structures of the embodiments and the structure after replacement are also included in the present invention. In addition, the combination in the embodiments, the order of processing, or various design changes and other deformations can be appropriately reorganized according to the knowledge of those skilled in the art, and the embodiments obtained by applying such deformations can also be included in the scope of the present invention.

[0058] This application is based on Japanese Patent Application No. 2022-147366 filed on September 15, 2022, the contents of which are incorporated herein by reference.

Claims

1. A vehicle lighting unit, characterized in that: have: The first light source; a second light source, the second light source being arranged adjacent to the first light source; A reflector, the reflector having: a first reflecting surface, which reflects a portion of the light emitted from the first light source toward the front of the lamp; a second reflecting surface, which reflects a portion of the light emitted from the second light source toward the front of the lamp; and a main back surface, which is opposite to the emission surface of the first light source and the emission surface of the second light source; as well as A metal plate having a main shielding portion that shields light from the first light source toward the main back surface and light from the second light source toward the main back surface.

2. The vehicle lamp unit according to claim 1, characterized in that: The metal plate has a thickness of 0.2 mm to 0.6 mm.

3. The vehicle lamp unit according to claim 1 or 2, characterized in that: The reflector also has: an upper reflector having a third reflecting surface opposite to the first reflecting surface and reflecting a portion of the light emitted from the first light source toward the front of the lamp; and a lower reflector having a fourth reflecting surface opposite to the second reflecting surface and reflecting a portion of the light emitted from the second light source toward the front of the lamp, The upper reflector has an upper back surface opposite to the emission surface of the first light source, The lower reflector has a lower back surface opposite to the emission surface of the second light source, The metal plate has: an upper shielding portion for shielding light from the first light source toward the upper back surface; and a lower shielding portion for shielding light from the second light source toward the lower back surface.

4. The vehicle lamp unit according to claim 1 or 2, characterized in that: The reflector includes a shading cover portion, and the shading cover portion forms a cut-off line of a light distribution pattern at front ends of the first reflecting surface and the second reflecting surface. The light shielding cover portion includes a liquid crystal polymer and has a thickness of 0.2 mm or less.

5. The vehicle lamp unit according to claim 3, characterized in that: The vehicle lamp unit further comprises: A projection lens, the projection lens being used to project a light distribution pattern toward the front of the lamp using light emitted from at least one of the first light source and the second light source; as well as a circuit substrate, the circuit substrate carrying the first light source and the second light source, In the circuit substrate, a driving circuit for driving the first light source and the second light source is mounted below the first light source and the second light source. The metal plate further includes a circuit protection portion, and the circuit protection portion extends from the lower shielding portion toward below the lamp so as to be located between the driving circuit and the projection lens.

6. The vehicle lamp unit according to claim 1 or 2, characterized in that: The reflector is fixed to the main shielding portion.

7. The vehicle lamp unit according to claim 1 or 2, characterized in that: The reflector is provided with a positioning pin protruding from the back side to the side opposite to the front side of the vehicle, The metal plate is formed with a positioning hole into which the positioning pin is inserted.

Images