Vehicular lighting device and vehicular lighting fixture

Abstract

To provide a vehicular lighting device which can improve adhesive strength between a substrate of a light emitting module and an adhesive layer, and to provide a vehicular lighting fixture.SOLUTION: A vehicular lighting device includes: a socket; a substrate which is provided on one end part side of the socket, which includes a first surface and a second surface opposing to the first surface, and in which at least one of a recess part opening to the first surface and a hole penetrating between the first surface and the second surface is provided; a light emitting element provided on the second surface side of the substrate; and an adhesive layer provided between the socket and the first surface of the substrate, and adhered to at least one of an inner wall of the recess part and an inner wall of the hole and to the first surface.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] Embodiments of the present invention relate to a vehicle lighting device and a vehicle lamp.

Background Art

[0002] From the viewpoints of energy saving and long life, instead of a vehicle lighting device including a lamp having a filament, a vehicle lighting device including a light emitting element such as a light emitting diode has been increasingly popularized. Such a vehicle lighting device includes a socket and a light emitting module provided on one end side of the socket. The light emitting module includes, for example, a substrate and a light emitting element provided on the substrate. The substrate of the light emitting module is adhered to one end side of the socket.

[0003] Here, with the lighting and extinguishing of the light emitting element provided in the vehicle lighting device, the temperature of the substrate and the temperature of the adhesive layer formed by curing of the adhesive change. Further, for example, in the case of a vehicle lighting device provided in an automobile, the temperature of the use environment is -40°C to 85°C. Therefore, the temperature of the substrate and the temperature of the adhesive layer also change due to the change in the temperature of the use environment. When the temperature of the substrate and the temperature of the adhesive layer change, a thermal stress is generated between the substrate and the adhesive layer. In addition, vibrations and impacts associated with running are applied to the vehicle lighting device.

[0004] Therefore, if the adhesive strength between the substrate of the light emitting module and the adhesive layer is weak, the light emitting module may fall off from the socket. Therefore, the development of a technology capable of improving the adhesive strength between the substrate of the light emitting module and the adhesive layer has been desired.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The problem to be solved by the present invention is to provide a vehicle lighting device and a vehicle lamp that can improve the adhesive strength between the substrate of a light-emitting module and an adhesive layer.

Means for Solving the Problems

[0007] The vehicle lighting device according to the embodiment includes a socket; a substrate provided on one end side of the socket, having a first surface and a second surface facing the first surface, and provided with at least one of a recess opening in the first surface and a hole penetrating between the first surface and the second surface; a light-emitting element provided on the second surface side of the substrate; and an adhesive layer provided between the socket and the first surface of the substrate, and adhering to at least one of the inner wall of the recess and the inner wall of the hole and the first surface.

Effects of the Invention

[0008] According to the embodiment of the present invention, it is possible to provide a vehicle lighting device and a vehicle lamp that can improve the adhesive strength between the substrate of a light-emitting module and an adhesive layer.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiment for Carrying out the Invention

[0010] Hereinafter, embodiments will be exemplified with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals, and detailed descriptions thereof are omitted as appropriate.

[0011] (Vehicle Lighting Device) The vehicle lighting device 1 according to the present embodiment can be provided, for example, in an automobile or a railway vehicle. Examples of the vehicle lighting device 1 provided in an automobile include, for example, a front combination lamp (for example, a combination of a daytime running lamp (DRL), a position lamp, a turn signal lamp, etc. as appropriate), and a rear combination lamp (for example, a combination of a stop lamp, a tail lamp, a turn signal lamp, a back lamp, a fog lamp, etc. as appropriate). However, the use of the vehicle lighting device 1 is not limited to these.

[0012] FIG. 1 is a schematic exploded view for illustrating the vehicle lighting device 1 according to the present embodiment. FIG. 2 is a cross-sectional view taken along line A-A of the vehicle lighting device 1 in FIG. 1. As shown in FIGS. 1 and 2, the vehicle lighting device 1 is provided with, for example, a socket 10, a light emitting module 20, a power supply unit 30, a heat transfer unit 40, and an adhesive layer 50.

[0013] The socket 10 has, for example, a mounting portion 11, a bayonet 12, a flange 13, heat radiation fins 14, and a connector holder 15. The mounting portion 11 is provided on the surface of the flange 13 opposite to the side where the heat dissipation fins 14 are provided. The outer shape of the mounting portion 11 is, for example, cylindrical. The mounting portion 11 has, for example, a recess 11a that opens at the end opposite to the flange 13 side.

[0014] The bayonet 12 is provided, for example, on the side surface of the mounting portion 11. The bayonet 12 protrudes toward the outside of the vehicle lighting device 1. The bayonet 12 faces the flange 13. A plurality of bayonets 12 can be provided. The bayonet 12 is used when mounting the vehicle lighting device 1 to the housing 101 of the vehicle lamp 100 described later, for example. The bayonet 12 can be used for a twist lock.

[0015] The flange 13 is plate-shaped. The flange 13 has, for example, a substantially disc shape. The side surface of the flange 13 is located outside the vehicle lighting device 1 compared to the side surface of the bayonet 12.

[0016] The heat dissipation fins 14 are provided on the flange 13 on the side opposite to the mounting portion 11 side. At least one heat dissipation fin 14 can be provided. For example, as shown in FIGS. 1 and 2, a plurality of heat dissipation fins 14 can be provided on the socket 10. The plurality of heat dissipation fins 14 can be arranged in a predetermined direction. The heat dissipation fins 14 have, for example, a plate shape or a cylindrical shape.

[0017] The connector holder 15 is provided on the flange 13 on the side opposite to the mounting portion 11 side. The connector holder 15 can be provided side by side with the heat dissipation fins 14. The connector holder 15 has a cylindrical shape, and a connector 105 having a seal member 105a inside is inserted therein.

[0018] The socket 10 has a function of holding the light emitting module 20 and the power supply unit 30, and a function of transmitting the heat generated in the light emitting module 20 to the outside. Therefore, the socket 10 is preferably formed of a material having a high thermal conductivity. The socket 10 can be formed of a metal such as an aluminum alloy, for example.

[0019] Further, the socket 10 can also be formed of, for example, a highly thermally conductive resin. The highly thermally conductive resin is a resin such as PET (Polyethylene terephthalate) or Nylon, with fillers such as carbon or aluminum oxide mixed therein. If the socket 10 includes the highly thermally conductive resin, heat generated in the light-emitting module 20 can be efficiently dissipated. Also, the weight of the socket 10 can be reduced. Note that the socket 10 illustrated in FIGS. 1 and 2 is a socket formed of a highly thermally conductive resin.

[0020] The light-emitting module 20 (substrate 21) is provided on one end side of the socket 10. FIG. 3 is a schematic plan view when the light-emitting module 20 is viewed from a direction along the central axis 1a of the vehicle lighting device 1. As shown in FIGS. 1 to 3, the light-emitting module 20 has, for example, a substrate 21, a light-emitting element 22, a frame portion 23, a sealing portion 24, and a circuit element 25.

[0021] The substrate 21 is adhered to, for example, the end face of the heat transfer portion 40. When the heat transfer portion 40 is omitted, for example, the substrate 21 is adhered to the bottom face 11a1 of the concave portion 11a or the like. Note that details regarding the adhesion of the substrate 21 will be described later.

[0022] The substrate 21 has a plate shape. The substrate 21 has a face 21c (corresponding to an example of a first face) and a face 21b (corresponding to an example of a second face) facing the face 21c. The planar shape of the substrate 21 (the shape when viewed from a direction along the central axis 1a of the vehicle lighting device 1) is, for example, a substantially quadrangle. The substrate 21 can be formed of, for example, an inorganic material such as ceramics (e.g., aluminum oxide or aluminum nitride), or an organic material such as paper phenol or glass epoxy. Also, the substrate 21 may be a metal core substrate in which the surface of a metal plate is coated with an insulating material. The substrate 21 may have a single-layer structure or a multilayer structure.

[0023] When considering heat dissipation of the heat generated when the light-emitting element 22 is lit, it is preferable to use a substrate 21 with high thermal conductivity. For example, if the substrate 21 is formed of ceramics or is a metal core substrate, the heat generated when the light-emitting element 22 is lit can be efficiently dissipated.

[0024] Also, the substrate 21 has a wiring pattern 21a. The wiring pattern 21a is provided, for example, on the surface 21b of the substrate 21. The wiring pattern 21a is formed of, for example, a material mainly composed of silver or a material mainly composed of copper. Also, a coating portion that covers the wiring pattern 21a and a film-like resistor described later can be provided. The coating portion can include, for example, a glass material.

[0025] The light-emitting element 22 is provided on the surface 21b side of the substrate 21. The light-emitting element 22 is electrically connected to the wiring pattern 21a. At least one light-emitting element 22 can be provided. The vehicle lighting device 1 (light-emitting module 20) illustrated in FIGS. 1 and 2 is provided with a plurality of light-emitting elements 22. When a plurality of light-emitting elements 22 are provided, the plurality of light-emitting elements 22 can be connected in series.

[0026] The light-emitting element 22 can be, for example, a light-emitting diode, an organic light-emitting diode, a laser diode, or the like.

[0027] The light-emitting element 22 can be any of a chip-shaped light-emitting element, a surface-mount type light-emitting element such as a PLCC (Plastic Leaded Chip Carrier) type, and a light-emitting element having lead wires such as a bullet type. However, if the light-emitting element 22 is a chip-shaped light-emitting element, the light-emitting module 20 can be miniaturized, and thus the vehicle lighting device 1 can be miniaturized.

[0028] In the following, as an example, the case where the light-emitting element 22 is a chip-shaped light-emitting element will be described. The chip-shaped light-emitting element 22 can be electrically connected to the wiring pattern 21a by COB (Chip On Board). The chip-shaped light-emitting element 22 may be any of an upper electrode type light-emitting element, an upper and lower electrode type light-emitting element, and a flip chip type light-emitting element.

[0029] The frame portion 23 has a frame shape and surrounds the light-emitting element 22. The frame portion 23 can be adhered to the surface 21b of the substrate 21 using an adhesive. The contour (planar shape contour) of the frame portion 23 when viewed from the direction along the central axis 1a of the vehicle lighting device 1 can be appropriately changed according to the required light distribution characteristics, luminance distribution, etc. For example, the planar shape contour of the frame portion 23 can be a circle, a quadrangle, an ellipse, etc. Note that the planar shape contour of the frame portion 23 illustrated in FIGS. 1 and 2 is a circle.

[0030] The frame portion 23 is formed of, for example, a resin. The resin can be, for example, a thermoplastic resin such as PBT (polybutylene terephthalate), PC (polycarbonate), PET, nylon, PP (polypropylene), PE (polyethylene), PS (polystyrene).

[0031] The frame portion 23 has a function of a reflector that reflects the light emitted from the light-emitting element 22 and a function of defining the formation range of the sealing portion 24. Therefore, if the frame portion 23 is provided, the extraction efficiency of the light emitted from the light-emitting element 22 can be improved. Also, if the frame portion 23 is provided, the formation range of the sealing portion 24 can be reduced, so that the light-emitting module 20 can be miniaturized, and thus the vehicle lighting device 1 can be miniaturized.

[0032] The sealing portion 24 is provided inside the frame portion 23. The sealing portion 24 is provided so as to cover the area surrounded by the frame portion 23. The sealing portion 24 is provided so as to cover the light-emitting element 22. The sealing portion 24 contains a resin having translucency. The sealing portion 24 is formed, for example, by filling resin inside the frame portion 23. The filling of the resin is performed, for example, using a dispenser or the like. The resin to be filled is, for example, a silicone resin or the like. Also, a phosphor can be included in the sealing portion 24. In addition, when the light-emitting element 22 is a surface-mount type light-emitting element or a light-emitting element having lead wires such as a bullet type, the frame portion 23 and the sealing portion 24 can be omitted.

[0033] In addition, an optical element or the like can be provided as necessary. The optical element is, for example, a convex lens, a concave lens, a light guide, or the like. The optical element can be provided, for example, on the sealing portion 24.

[0034] The circuit element 25 can be a passive element or an active element used to form a light-emitting circuit having the light-emitting element 22. The circuit element 25 is provided, for example, on the surface 21b side of the substrate 21. The circuit element 25 is provided, for example, around the frame portion 23 and is electrically connected to the wiring pattern 21a. The circuit element 25 is electrically connected to the light-emitting element 22 via the wiring pattern 21a.

[0035] The circuit elements 25 illustrated in FIGS. 1 and 3 are, for example, a resistor 25a, a protection element 25b, and a control element 25c. However, the type of the circuit element 25 is not limited to the illustrated ones and can be appropriately changed according to the configuration of the light-emitting circuit having the light-emitting element 22. For example, in addition to the ones described above, the circuit element 25 may be a capacitor, a positive temperature coefficient thermistor, a negative temperature coefficient thermistor, an inductor, a surge absorber, a varistor, a transistor, an integrated circuit, an arithmetic element, or the like.

[0036] The resistor 25a can be, for example, a surface-mounted resistor, a resistor with leads (metal oxide film resistor), a film resistor formed using a screen printing method, etc. Note that the resistor 25a illustrated in FIGS. 1 and 3 is a film resistor.

[0037] Here, since there are variations in the forward voltage characteristics of the light-emitting element 22, if the applied voltage between the anode terminal and the ground terminal is made constant, variations will occur in the brightness (luminous flux, luminance, luminous intensity, illuminance) of the light emitted from the light-emitting element 22. Therefore, in order for the brightness of the light emitted from the light-emitting element 22 to fall within a predetermined range, the value of the current flowing through the light-emitting element 22 is made to be within a predetermined range by the resistor 25a connected in series with the light-emitting element 22. In this case, by changing the resistance value of the resistor 25a, the value of the current flowing through the light-emitting element 22 is made to be within a predetermined range.

[0038] When the resistor 25a is a surface-mounted resistor or a resistor with leads, etc., a resistor 25a having an appropriate resistance value is selected according to the forward voltage characteristics of the light-emitting element 22. When the resistor 25a is a film resistor, if a part of the resistor 25a is removed, the resistance value can be increased. For example, if a film resistor is irradiated with laser light, a part of the film resistor can be easily removed. Note that the number, arrangement, size, etc. of the resistor 25a are not limited to those illustrated, and can be appropriately changed according to the number and specifications of the light-emitting element 22, etc.

[0039] The protection element 25b is provided, for example, to prevent a reverse voltage from being applied to the light-emitting element 22 and to prevent pulse noise from the reverse direction from being applied to the light-emitting element 22. The protection element 25b can be, for example, a diode. The protection element 25b illustrated in FIGS. 1 and 3 is a surface-mounted diode.

[0040] The control element 25c is provided, for example, to switch the voltage applied to the light-emitting element 22, to perform temperature derating, or to control the current flowing through the light-emitting element 22. However, the functions and applications of the control element 25c are not limited to those exemplified. The control element 25c can be, for example, a transistor or an integrated circuit. Note that the control element 25c exemplified in FIGS. 1 and 3 is a surface-mounted integrated circuit.

[0041] The power supply unit 30 has, for example, a plurality of power supply terminals 31 and a holding unit 32. The plurality of power supply terminals 31 can be rod-shaped bodies. One end of the plurality of power supply terminals 31 protrudes from the bottom surface 11a1 of the concave portion 11a. One end of the plurality of power supply terminals 31 is soldered to the wiring pattern 21a provided on the substrate 21. The other end of the plurality of power supply terminals 31 is exposed inside the hole of the connector holder 15. A connector 105 is fitted onto the plurality of power supply terminals 31 exposed inside the hole of the connector holder 15. The plurality of power supply terminals 31 are formed of a metal such as a copper alloy, for example. Note that the shape, arrangement, material, etc. of the plurality of power supply terminals 31 are not limited to those exemplified and can be changed as appropriate.

[0042] When the socket 10 is formed using, for example, a high thermal conductivity resin containing a filler using carbon, or a metal, etc., the socket 10 has conductivity. Therefore, the holding unit 32 is provided to insulate between the plurality of power supply terminals 31 and the conductive socket 10. Note that when the socket 10 is formed using an insulating high thermal conductivity resin (for example, a high thermal conductivity resin containing a filler using aluminum oxide, etc.), the holding unit 32 can be omitted. The holding unit 32 can be, for example, press-fitted into a hole provided in the socket 10 or adhered to the inner wall of the hole.

[0043] The heat transfer part 40, for example, has a plate shape and is provided between the socket 10 and the adhesive layer 50. For example, the heat transfer part 40 is adhered to the bottom surface 11a1 of the recess 11a. Note that the adhesive can be the same as the adhesive that adheres the substrate 21 and the heat transfer part 40, which will be described later. When the adhesive cures, an adhesive layer 40a is formed between the heat transfer part 40 and the bottom surface 11a1 of the recess 11a, for example. Also, the heat transfer part 40 can be adhered to the inside of the recess provided on the bottom surface 11a1 of the recess 11a, the heat transfer part 40 can be attached to the inside of the recess via thermal conductive grease (heat dissipation grease), or the heat transfer part 40 can be embedded in the inside of the recess by an insert molding method.

[0044] The heat transfer part 40 is formed from a material with high thermal conductivity. For example, the heat transfer part 40 is formed from a metal such as aluminum, an aluminum alloy, copper, or a copper alloy. Note that when the socket 10 is formed from a metal or when the heat generated in the light emitting module 20 is small, the heat transfer part 40 can be omitted.

[0045] Next, the adhesion of the substrate 21 will be further described. The substrate 21 is adhered to the end face of the heat transfer part 40, for example. When the heat transfer part 40 is omitted, the substrate 21 is adhered to the bottom surface 11a1 of the recess 11a of the socket 10, for example. In this case, if the substrate 21 is adhered using an adhesive with high thermal conductivity, the heat generated when the light emitting element 22 is lit can be efficiently transmitted to the socket 10. Therefore, it is possible to suppress the temperature of the light emitting element 21 from exceeding the maximum junction temperature.

[0046] For example, the adhesive can contain a filler using an inorganic material such as aluminum oxide. The thermal conductivity of the adhesive can be, for example, 0.5 W / (m·K) or more and 10 W / (m·K) or less. When the adhesive cures, the adhesive layer 50 is formed. Therefore, the thermal conductivity of the adhesive layer 50 is, for example, 0.5 W / (m·K) or more and 10 W / (m·K) or less.

[0047] Here, as the light-emitting element 22 turns on and off, the temperature of the substrate 21 and the temperature of the adhesive layer 50 change. Also, for example, in the case of the vehicle lighting device 1 provided in an automobile, the temperature of the use environment is -40°C to 85°C. Therefore, the temperature of the substrate 21 and the temperature of the adhesive layer 50 also change due to the change in the temperature of the use environment.

[0048] When the temperature of the substrate 21 and the temperature of the adhesive layer 50 change, a thermal stress is generated between the substrate 21 and the adhesive layer 50. In addition, the vehicle lighting device 1 is subjected to vibrations during running and impacts associated with the opening and closing of the bonnet and doors. Therefore, if the adhesive strength between the substrate 21 and the adhesive layer 50 is weak, the light-emitting module 20 (substrate 21) may fall off from the socket 10.

[0049] Therefore, at least one recess 21d is provided in the substrate 21. Five recesses 21d are provided in the substrate 21 illustrated in FIGS. 1 and 3. FIG. 4 is a schematic cross-sectional view for exemplifying the recess 21d. Note that FIG. 4 is a schematic enlarged view of part B in FIG. 2. As shown in FIG. 4, the recess 21d opens to the surface 21c of the substrate 21 on the adhesive layer 50 side. The recess 21d can be formed, for example, by irradiating the surface 21c of the substrate 21 with laser light.

[0050] If the recess 21d that opens to the surface 21c of the substrate 21 on the adhesive layer 50 side is provided, an adhesive for adhering the substrate 21 can be introduced into the recess 21d. Therefore, when the adhesive cures, a part of the adhesive layer 50 is provided inside the recess 21d. If a part of the adhesive layer 50 is provided inside the recess 21d, the adhesive strength of the light-emitting module 20 (substrate 21) in the direction parallel to the surface 21c of the substrate 21 can be improved. Also, if a part of the adhesive layer 50 is provided inside the recess 21d, the adhesive area of the substrate 21 increases, so the adhesive strength of the light-emitting module 20 (substrate 21) in the direction perpendicular to the surface 21c of the substrate 21 can be improved. As described above, the adhesive layer 50 adheres to the inner wall of the recess 21d and the surface 21c of the substrate 21.

[0051] The depth dimension, opening dimension, opening shape, etc. of the recess 21d are not particularly limited. However, when the substrate 21 is formed of a brittle material such as ceramics, if the depth dimension of the recess 21d is made too large, the substrate 21 may crack or develop cracks. For example, when the substrate 21 contains ceramics, the depth of the recess 21d can be set to be half or less of the thickness of the substrate 21. By doing so, it is possible to suppress the occurrence of cracks and fissures in the substrate 21. When the substrate 21 contains aluminum oxide and the thickness of the substrate 21 is about 1 mm, it is more preferable that the depth dimension of the recess 21d is about 0.05 mm to 0.1 mm.

[0052] Also, if the shortest distance between the recess 21d and the side of the substrate 21 becomes too short, the substrate 21 may crack or develop cracks. For example, when the substrate 21 is formed of aluminum oxide and the thickness of the substrate 21 is about 1 mm, it is preferable that the shortest distance between the recess 21d and the side of the substrate 21 is 1 mm or more. By doing so, it is possible to suppress the occurrence of cracks and fissures in the substrate 21.

[0053] Also, when the opening shape of the recess 21d has corners such as a quadrangle, there is also a risk that the substrate 21 may crack or develop cracks. For example, when the substrate 21 is formed of aluminum oxide and the thickness of the substrate 21 is about 1 mm, it is preferable that the opening shape of the recess 21d is a circle, an ellipse, or the like. By doing so, it is possible to suppress the occurrence of cracks and fissures in the substrate 21.

[0054] When the substrate 21 is formed of an organic material such as glass epoxy or is a metal core substrate, etc., it is difficult for the substrate 21 to crack or develop cracks, so the depth dimension, opening dimension, opening shape, etc. of the recess 21d can be set arbitrarily.

[0055] Also, the heat generation amount of the light-emitting element 21 is larger than that of the circuit element 25. Therefore, when viewed from the direction along the central axis 1a of the vehicle lighting device 1, if the recess 21d is provided at a position overlapping the light-emitting element 21, there is a possibility that the heat generated in the light-emitting element 21 is difficult to be transmitted to the socket 10 side. Therefore, as shown in FIG. 3, when viewed from the direction along the central axis 1a of the vehicle lighting device 1, it is preferable that the recess 21d does not overlap the light-emitting element 21.

[0056] Also, when viewed from the direction along the central axis 1a of the vehicle lighting device 1, it is preferable that the recess 21d does not overlap the circuit element 25 as much as possible. In this case, the heat generation amount varies depending on the use and type of the circuit element 25. For example, in a circuit element directly electrically connected to the light-emitting element 21, since the current flowing through the light-emitting element 21 flows, the heat generation amount increases. On the other hand, in a circuit element not directly electrically connected to the light-emitting element 21, a control current or the like flows, so a smaller current flows compared to the current flowing through the light-emitting element 21. Therefore, the heat generation amount of the circuit element not directly electrically connected to the light-emitting element 22 is smaller than the heat generation amount of the circuit element directly electrically connected to the light-emitting element 22. Therefore, when viewed from the direction along the central axis 1a of the vehicle lighting device 1, it is preferable that the recess 21d does not overlap the circuit element directly electrically connected to the light-emitting element 21.

[0057] Also, if the number of the recesses 21d increases, the adhesive strength of the light-emitting module 20 (substrate 21) can be further improved. However, if the number of the recesses 21d is increased too much, there is a possibility that the substrate 21 is easily cracked or chipped, or the heat generated in the light-emitting element 21 is difficult to be transmitted to the socket 10 side.

[0058] The depth dimension, opening dimension, opening shape, number, and arrangement of the recess 21d can be appropriately changed according to the material and dimensions of the substrate 21, the arrangement of the light-emitting element 21 and the circuit element 25, the required adhesive strength, and the like. The depth dimension, opening dimension, opening shape, number, and arrangement of the recess 21d can be appropriately determined, for example, by conducting experiments or simulations.

[0059] Here, for the adhesion of the substrate 21, an adhesive is applied in dots to the surface to which the substrate 21 is to be adhered (for example, the end face of the heat transfer part 40 or the bottom face 11a1 of the recess 11a), and the substrate 21 is pressed against the adhesives applied in dots so as to spread the adhesives applied in dots. In this case, a dispenser or the like can be used to apply the adhesive in dots.

[0060] Therefore, when viewed from the direction along the central axis 1a of the vehicle lighting device 1, if the recess 21d overlaps with the position where the adhesive is applied in dots, it becomes easier to fill the inside of the recess 21d with the adhesive. Therefore, it is possible to suppress variations in the adhesive strength.

[0061] FIGS. 5(a) to 5(c) are schematic cross-sectional views for exemplifying recesses 21da to 21dc according to other embodiments. As shown in FIG. 5(a), the cross-sectional dimension of the recess 21da gradually decreases as it moves away from the surface 21c of the substrate 21. As shown in FIG. 5(b), the cross-sectional dimension of the recess 21db decreases stepwise as it moves away from the surface 21c of the substrate 21. If the recesses are formed like the recess 21da and the recess 21db, the surface areas of the recess 21da and the recess 21db increase, so that it becomes easy to improve the adhesive strength. Also, as shown in FIG. 5(c), the recess 21dc is composed of a curved surface. In this way, even when the substrate 21 is formed of a brittle material such as aluminum oxide, it is possible to suppress cracks and fissures from occurring in the substrate 21.

[0062] The above describes the case where the recess 21d opening to the surface 21c of the substrate 21 is provided, but a hole penetrating between the surface 21c and the surface 21b of the substrate 21 can also be provided. In this case, the adhesive layer 50 adheres to the inner wall of the hole and the surface 21c of the substrate 21. Also, similar to the above-described recess 21d, when viewed from the direction along the central axis 1a of the vehicle lighting device 1, the hole can be made not to overlap with the light-emitting element 21. The hole can be provided in the substrate 21 instead of the recess 21d, or together with the recess 21d.

[0063] FIG. 6(a) and FIG. 6(b) are schematic cross-sectional views for exemplifying the holes 21d1 and 21d2 penetrating the substrate 21. As shown in FIG. 6(a), if the hole 21d1 penetrating between the surface 21c and the surface 21b of the substrate 21 is provided, a part of the adhesive can be attached to the surface 21b of the substrate 21. Therefore, the adhesive strength in the direction perpendicular to the surface 21c of the substrate 21 can be further improved.

[0064] Also, as shown in FIG. 6(b), if a step is provided such that the cross-sectional dimension of the hole 21d2 on the surface 21b side is larger than the cross-sectional dimension of the hole 21d2 on the surface 21b side, a part of the adhesive can be attached to the step portion. Therefore, the adhesive strength in the direction perpendicular to the surface 21c of the substrate 21 can be further improved. Also, since a part of the adhesive adhering to the surface 21b of the substrate 21 can be suppressed, it is possible to suppress the impairment of the aesthetic appearance.

[0065] (Vehicle lighting fixture) In one embodiment of the present invention, a vehicle lighting fixture 100 including the vehicle lighting device 1 can be provided. The above-described description regarding the vehicle lighting device 1 and the modified examples of the vehicle lighting device 1 (for example, those in which a person skilled in the art appropriately adds, deletes, or changes the design of the components and has the features of the present invention) can all be applied to the vehicle lighting fixture 100.

[0066] In the following, as an example, the case where the vehicle lamp 100 is a rear combination lamp provided on an automobile will be described. However, the vehicle lamp 100 is not necessarily limited to the rear combination lamp provided on an automobile. The vehicle lamp 100 may be any vehicle lamp provided on an automobile, a railway vehicle, or the like.

[0067] FIG. 7 is a schematic partial cross-sectional view for illustrating the vehicle lamp 100. As shown in FIG. 7, the vehicle lamp 100 includes, for example, a vehicle lighting device 1, a housing 101, a cover 102, an optical element 103, a seal member 104, and a connector 105.

[0068] The vehicle lighting device 1 is attached to the housing 101. The housing 101 holds the mounting portion 11. The housing 101 has a box shape with one end open. The housing 101 is formed of, for example, a resin that does not transmit light. On the bottom surface of the housing 101, a mounting hole 101a into which the portion of the mounting portion 11 provided with the bayonet 12 is inserted is provided. A recess into which the bayonet 12 provided on the mounting portion 11 is inserted is provided at the periphery of the mounting hole 101a. Although the case where the mounting hole 101a is directly provided in the housing 101 is illustrated, a mounting member having the mounting hole 101a may be provided in the housing 101.

[0069] When attaching the vehicle lighting device 1 to the vehicle lamp 100, the portion of the mounting portion 11 provided with the bayonet 12 is inserted into the mounting hole 101a, and the vehicle lighting device 1 is rotated. Then, for example, the bayonet 12 is held by a fitting portion provided at the periphery of the mounting hole 101a. Such an attachment method is called a twist lock.

[0070] The cover 102 is provided so as to close the opening of the housing 101. The cover 102 is formed of a light-transmitting resin or the like. The cover 102 can also have functions such as a lens.

[0071] Light enters the optical element 103 from the vehicle lighting device 1. The optical element 103 performs functions such as reflecting, diffusing, guiding, condensing the light emitted from the vehicle lighting device 1, and forming a predetermined light distribution pattern. For example, the optical element 103 illustrated in FIG. 7 is a reflector. In this case, the optical element 103 reflects the light emitted from the vehicle lighting device 1 to form a predetermined light distribution pattern.

[0072] The seal member 104 is provided between the flange 13 and the housing 101. The seal member 104 has an annular shape and is formed of an elastic material such as rubber or silicone resin.

[0073] When the vehicle lighting device 1 is attached to the vehicle lamp 100, the seal member 104 is sandwiched between the flange 13 and the housing 101. Therefore, the seal member 104 can seal the internal space of the housing 101. Further, due to the elastic force of the seal member 104, the bayonet 12 is pressed against the housing 101. Therefore, it is possible to prevent the vehicle lighting device 1 from detaching from the housing 101.

[0074] The connector 105 is fitted to the ends of a plurality of power supply terminals 31 exposed inside the connector holder 15. A lighting circuit or the like provided outside the vehicle lamp 100 is electrically connected to the connector 105. Therefore, by fitting the connector 105 to the ends of the plurality of power supply terminals 31, the lighting circuit or the like and the light emitting element 22 can be electrically connected.

[0075] Further, a seal member 105a is provided on the connector 105. When the connector 105 having the seal member 105a is inserted into the connector holder 15, the inside of the connector holder 15 is sealed to be watertight.

[0076] As described above, several embodiments of the present invention have been illustrated. However, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, changes, etc. can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof. In addition, the above-described embodiments can be implemented in combination with each other.

[0077] The following shows the supplementary notes regarding the above-described embodiments.

[0078] (Supplementary Note 1) a socket; a substrate provided on one end side of the socket, having a first surface and a second surface facing the first surface, and provided with at least one of a recess opening on the first surface and a hole penetrating between the first surface and the second surface; a light-emitting element provided on the second surface side of the substrate; an adhesive layer provided between the socket and the first surface of the substrate, and adhering to at least one of the inner walls of the recess and the hole and the first surface; A vehicle lighting device comprising the above.

[0079] (Supplementary Note 2) The vehicle lighting device according to Supplementary Note 1, wherein the recess and the hole do not overlap with the light-emitting element when viewed from a direction along the central axis of the vehicle lighting device.

[0080] (Supplementary Note 3) the substrate includes ceramics, The vehicle lighting device according to Supplementary Note 1 or 2, wherein the depth of the recess is half or less of the thickness of the substrate.

[0081] (Supplementary Note 4) further comprising a heat transfer part provided between the socket and the adhesive layer, The socket is a vehicle lighting device according to any one of Appendices 1 to 3 containing a high thermal conductivity resin.

[0082] (Appendix 5) A vehicle lighting device according to any one of Appendices 1 to 4; A housing to which the vehicle lighting device is attached; A vehicle lamp comprising the same.

Explanation of Signs

[0083] 1 Vehicle lighting device, 1a Central axis, 10 Socket, 20 Light emitting module, 21 Substrate, 21b Surface, 21c Surface, 21d Recess, 21da to 21dc Recesses, 21d1 Hole, 21d2 Hole, 22 Light emitting element, 40 Heat transfer part, 50 Adhesive layer, 100 Vehicle lamp, 101 Housing

Claims

1. a socket; a substrate provided on one end side of the socket, having a first surface and a second surface facing the first surface, and provided with at least one of a recess opening on the first surface and a hole penetrating between the first surface and the second surface; a light-emitting element provided on the second surface side of the substrate; an adhesive layer provided between the socket and the first surface of the substrate, and adhering to at least one of the inner wall of the recess and the inner wall of the hole and the first surface; a vehicle lighting device comprising the above.

2. The vehicle lighting device according to claim 1, wherein when viewed from a direction along the central axis of the vehicle lighting device, the recess and the hole do not overlap with the light-emitting element.

3. The substrate includes ceramics, The vehicle lighting device according to claim 1 or 2, wherein the depth of the recess is not more than half of the thickness of the substrate.

4. further comprising a heat transfer part provided between the socket and the adhesive layer, The vehicle lighting device according to claim 1 or 2, wherein the socket contains a high thermal conductivity resin.

5. a vehicle lighting device according to claim 1; a housing to which the vehicle lighting device is attached; a vehicle lamp comprising the above.

Images