阅读说明：本技术 车辆用照明装置及车辆用灯具 (Lighting device for vehicle and lighting device for vehicle ) 是由 日野清和 于 2021-02-24 设计创作，主要内容包括：本发明提供一种能够提高散热性并且能够实现小型轻型化的车辆用照明装置及车辆用灯具。车辆用照明装置具备：灯座,包含高导热性树脂；发光模块；及传热部,包含金属,所述传热部设置在所述安装部与所述发光模块之间,并且,满足以下式,2.5≤W≤5.5,15≤WT≤25,40≤(A1-A2)×WT/W≤90,其中,W是施加于所述发光模块的电功率,其单位是瓦；WT是所述高导热性树脂的导热系数,其单位是瓦/(m·K)；A1为与所述车辆用照明装置的中心轴垂直的方向上的所述凸缘的尺寸,其单位是mm；A2为与所述车辆用照明装置的中心轴垂直的方向上的所述安装部的尺寸,其单位是mm；(A1-A2)×WT/W的单位是1/K。(The invention provides a lighting device for a vehicle and a lamp for the vehicle, which can improve heat dissipation and realize miniaturization and light weight. The vehicle lighting device includes: a lamp holder containing a high thermal conductive resin; a light emitting module; and a heat transfer portion including metal, the heat transfer portion being disposed between the mounting portion and the light emitting module and satisfying the following formula, 2.5W 5.5, 15 WT 25,40 (A1-A2) xWT/W90, wherein W is electric power applied to the light emitting module and has a unit of tile; WT is the thermal conductivity of the high thermal conductive resin, and the unit thereof is W/(m.K); a1 is a dimension of the flange in a direction perpendicular to a central axis of the vehicular illumination device, and its unit is mm; a2 is a dimension of the mounting portion in a direction perpendicular to a central axis of the vehicular illumination device, and its unit is mm; the unit of (A1-A2). times.WT/W is 1/K.)

1. A lighting device for a vehicle, comprising:

a lamp holder that contains a high thermal conductive resin and has a flange, a mounting portion provided on one side of the flange, and a heat sink provided on the opposite side of the flange from the mounting portion;

a light emitting module provided at an end of the mounting portion opposite to the flange side and having at least one light emitting element; and

a heat transfer portion including metal and disposed between the mounting portion and the light emitting module,

and, satisfying the following expression,

2.5≤W≤5.5，

15≤WT≤25,

40≤(A1-A2)×WT/W≤90，

wherein W is the electrical power applied to the light emitting module in watts; WT is the thermal conductivity of the high thermal conductive resin, and the unit thereof is W/(m.K); a1 is a dimension of the flange in a direction perpendicular to a central axis of the vehicular illumination device, and its unit is mm; a2 is a dimension of the mounting portion in a direction perpendicular to a central axis of the vehicular illumination device, and its unit is mm; the unit of (A1-A2). times.WT/W is 1/K.

2. The vehicular illumination device according to claim 1,

a dimension B between a light emitting surface of the light emitting element and an end surface of the heat sink opposite to the flange in a direction along a central axis of the vehicle lighting device satisfies the following equation,

25mm≤B≤30mm。

3. the vehicular illumination device according to claim 1 or 2,

also satisfies the following formula, A2 is less than or equal to 19 mm.

4. The vehicular illumination device according to claim 1 or 2,

the radiating fin is cylindrical.

5. A vehicle lamp is characterized by comprising:

the vehicular illumination device according to any one of claims 1 to 4;

and a housing to which the vehicle lighting device is attached.

Technical Field

Embodiments of the present invention relate to a lighting device for a vehicle and a vehicle lamp.

Background

There is a lighting device for a vehicle, which includes a lamp socket and a light emitting module having a light emitting element. The lamp holder is provided with: the heat sink includes a flange, a mounting portion provided on one side of the flange, and a heat sink provided on an opposite side of the flange from the mounting portion. The light emitting element is provided at an end portion of the mounting portion opposite to the flange side. In such a vehicle lighting device, heat generated in the light emitting diode is mainly transmitted to the flange via the mounting portion. Part of the heat transferred to the flange is released to the outside through a housing of a vehicle lamp to which the vehicle lighting device is attached. And, another part of the heat transferred to the flange is transferred to the heat sink and released from the heat sink to the outside.

Here, in recent years, in order to achieve downsizing and weight reduction of the vehicle lighting device, the size (outer diameter size) of the mounting portion and the size (outer diameter size) of the flange in the direction perpendicular to the central axis of the vehicle lighting device tend to be small. In order to reduce the weight of the vehicle lighting device, a socket made of a highly heat conductive resin instead of a metal such as aluminum has been used.

Since the outer diameter of the mounting portion and the outer diameter of the flange affect the heat conduction, simply reducing these dimensions may result in a reduction in heat dissipation. Further, since the thermal conductivity of the high thermal conductive resin is lower than that of the metal, the influence of the outer diameter of the mounting portion and the outer diameter of the flange on the heat dissipation performance becomes larger if the socket including the high thermal conductive resin is used.

In contrast, it is expected to develop a technology capable of improving heat dissipation and realizing miniaturization and weight reduction.

Patent document 1: japanese patent laid-open publication No. 2016 and No. 106351

Disclosure of Invention

The invention aims to provide a lighting device for a vehicle and a lighting device for the vehicle, which can improve heat dissipation performance and realize miniaturization and light weight.

The lighting device for a vehicle according to an embodiment includes: a lamp holder that contains a high thermal conductive resin and has a flange, a mounting portion provided on one side of the flange, and a heat sink provided on the opposite side of the flange from the mounting portion; a light emitting module provided at an end of the mounting portion opposite to the flange side and having at least one light emitting element; and a heat transfer portion which includes metal, is provided between the mounting portion and the light emitting module, and satisfies the following formula,

2.5≤W≤5.5，

15≤WT≤25,

40≤(A1-A2)×WT/W≤90，

wherein W is the electrical power applied to the light emitting module in watts; WT is the thermal conductivity of the high thermal conductive resin, and the unit thereof is W/(m.K); a1 is a dimension of the flange in a direction perpendicular to a central axis of the vehicular illumination device, and its unit is mm; a2 is a dimension of the mounting portion in a direction perpendicular to a central axis of the vehicular illumination device, and its unit is mm; the unit of (A1-A2). times.WT/W is 1/K.

In the vehicular illumination device, a dimension between a light emitting surface of the light emitting element and an end surface of the heat sink on a side opposite to the flange in a direction along a central axis of the vehicular illumination device is B, and the following expression is satisfied, where 25 mm. ltoreq. B.ltoreq.30 mm.

In the vehicular illumination device, A2 is not more than 19mm, and the following expression is satisfied.

In the lighting device for a vehicle, the heat sink has a cylindrical shape.

The vehicle lamp according to the embodiment includes: the lighting device for a vehicle; and a housing to which the vehicle lighting device is attached.

According to the embodiments of the present invention, it is possible to provide a lighting device for a vehicle and a lighting fixture for a vehicle, which can improve heat dissipation and can be reduced in size and weight.

Drawings

Fig. 1 is a schematic perspective view illustrating a vehicle lighting device according to the present embodiment.

Fig. 2 is a sectional view of the vehicular illumination device in fig. 1, taken along line a-a.

Fig. 3 is a table illustrating the influence of the difference between the outer diameter a1 of the flange and the outer diameter a2 of the mounting portion on the heat dissipation performance of the socket and the reduction in size and weight.

Fig. 4 is a table illustrating the influence of the length of the heat sink on the heat dissipation of the lamp socket and the reduction in size and weight.

Fig. 5 is a partial schematic sectional view for illustrating a vehicle lamp.

In the figure: 1-lighting device for vehicle, 1 a-center axis, 10-lamp holder, 11-mounting part, 13-flange, 14-heat sink, 20-light emitting module, 21-substrate, 22-light emitting element, 40-heat transfer part, 100-lighting device for vehicle, 101-frame.

Detailed Description

Hereinafter, embodiments will be described by way of example with reference to the accompanying drawings. In the drawings, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

(Lighting device for vehicle)

The vehicle lighting device 1 according to the present embodiment may be installed in, for example, an automobile, a railway vehicle, or the like. As the vehicle lighting device 1 installed in an automobile, for example, a front combination Lamp (for example, a combination Lamp in which a Daytime Running Lamp (DRL), a width Lamp, a turn signal Lamp, and the like are appropriately combined), a rear combination Lamp (for example, a combination Lamp in which a stop Lamp, a tail Lamp, a turn signal Lamp, a backup Lamp, a fog Lamp, and the like are appropriately combined), and the like can be used. However, the application of the vehicle lighting device 1 is not limited to this.

Fig. 1 is a schematic perspective view illustrating a vehicle lighting device 1 according to the present embodiment.

Fig. 2 is a cross-sectional view of the vehicular illumination device 1 in fig. 1 taken along line a-a.

As shown in fig. 1 and 2, the vehicle lighting device 1 may include a socket 10, a light emitting module 20, a power supply unit 30, and a heat transfer unit 40.

The lamp socket 10 may be provided with a mounting portion 11, an engaging pin 12, a flange 13, a heat sink 14, and a connector holder 15.

The mounting portion 11 is provided on the flange 13 side. The mounting portion 11 may have a cylindrical shape. The external shape of the mounting portion 11 may be, for example, a cylindrical shape. The mounting portion 11 has a recess 11a that opens at an end surface on the side opposite to the flange 13.

A plurality of engagement pins 12 may be provided on the outer side surface 11d of the mounting portion 11. The plurality of engagement pins 12 protrude outward of the vehicle lighting device 1. The plurality of engagement pins 12 face the flange 13. The plurality of engagement pins 12 can be used when the vehicle lighting device 1 is mounted on the housing 101 of the vehicle lamp 100. A plurality of dowel pins 12 may be used as twist locks.

The flange 13 is plate-shaped. The flange 13 may be, for example, disc-shaped. The outer side surface of the flange 13 is located further to the outside of the vehicle lighting device 1 than the outer side surface of the engaging pin 12.

The heat sink 14 may be provided on the side of the flange 13 opposite to the mounting portion 11 side. At least one heat sink 14 may be provided. The number of the fins 14 may be appropriately changed according to the size of the flange 13 and the like. When a plurality of fins 14 are provided, the plurality of fins 14 may be arranged in a predetermined direction.

As shown in fig. 1 and 2, the heat sink 14 may have a cylindrical shape. That is, the heat sink 14 may have a columnar shape and a concave portion 14a opened at an end surface on the side opposite to the flange 13 side.

Here, when the vehicle lighting device 1 is mounted to the housing 101 of the vehicle lighting device 100 by the twist-lock method, the operator may grip the outer side surface of the heat sink 14. When the cylindrical heat radiating fins 14 are used, the bending rigidity can be increased as compared with the case of using plate-shaped heat radiating fins, and therefore, even if an operator grips the outer side surfaces of the heat radiating fins 14, the heat radiating fins 14 can be prevented from being damaged.

On the other hand, if the plate-shaped heat dissipating fins are used, the number of the heat dissipating fins can be increased, and thus the heat dissipating area can be increased. If the heat radiation area can be increased, the heat radiation performance can be improved.

In recent years, a reduction in size and weight of the vehicle illumination device 1 has been desired. Therefore, the dimension of the mounting portion 11 (the outer diameter dimension a2) and the dimension of the flange 13 (the outer diameter dimension a1) in the direction perpendicular to the central axis 1a of the vehicle illumination device 1 tend to be small. When the outer diameter a1 of the flange 13 is small, the distance between the central axis 1a and the outer side surface of the heat sink 14 is small, and therefore, the force (rotational force) that needs to be applied to the heat sink 14 when the vehicle illumination device 1 is attached is large. If the force required to be applied to the heat sink 14 is increased, the heat sink 14 is easily broken.

As will be described later, in view of weight reduction of the vehicle lighting device 1, the socket 10 is preferably made of a highly heat conductive resin. However, since the highly thermally conductive resin is more brittle than a metal such as aluminum, if the lamp socket 10 (heat sink 14) is made of the highly thermally conductive resin, the heat sink 14 is easily broken. The high thermal conductive resin may be a resin containing a filler made of an inorganic material and a resin, for example. The highly thermally conductive resin may be a resin obtained by mixing a filler made of carbon, alumina, or the like with a resin such as PET (Polyethylene terephthalate) or nylon.

Since the cylindrical heat sink 14 can increase the bending rigidity, the heat sink 14 can be prevented from being damaged even if the outer diameter a1 of the flange 13 is reduced or the base 10 made of a highly heat conductive resin is used to reduce the size and weight.

The connector holder 15 may be provided on the side of the flange 13 opposite to the mounting portion 11 side. The connector holder 15 is cylindrical. The connector 105 having the sealing member 105a is inserted into the interior of the connector housing 15. Therefore, the cross-sectional shape and the cross-sectional size of the hole of the connector holder 15 are matched with those of the connector 105 having the seal member 105 a.

The heat generated in the light emitting module 20 is mainly discharged to the outside via the lamp socket 10. Therefore, the lamp socket 10 is preferably made of a material having a high thermal conductivity. As the material having a high thermal conductivity, a metal such as aluminum can be used, but a highly thermal conductive resin is preferably used in view of weight reduction of the lamp socket 10.

For example, the mounting portion 11, the joint pin 12, the flange 13, the heat sink 14, and the connector holder 15 may be integrally molded by injection molding or the like. The lamp socket 10 and the power supply portion 30 may be integrally molded by insert molding or the like, or the lamp socket 10, the power supply portion 30, and the heat transfer portion 40 may be integrally molded by insert molding or the like.

The light emitting module 20 (substrate 21) may be provided at an end portion of the mounting portion 11 opposite to the flange 13 side.

Light-emitting module 20 may include substrate 21, light-emitting element 22, resistor 23, control element 24, capacitor 25, frame 26, sealing portion 27, and covering portion 28.

The substrate 21 has a plate shape. The planar shape of the substrate 21 may be a quadrangle, for example. The substrate 21 may be bonded to a surface 40a of the heat transfer portion 40 opposite to the bottom surface 11a1 of the recess 11a, for example. In this case, the adhesive preferably has a high thermal conductivity. For example, as the adhesive, an adhesive mixed with a filler made of an inorganic material can be used. The substrate 21 may be made of, for example, an inorganic material such as ceramic (e.g., alumina or aluminum nitride), an organic material such as phenol paper or glass epoxy, or the like. The substrate 21 may be a metal plate whose surface is coated with an insulating material. When the amount of heat generated by the light emitting element 22 is large, the substrate 21 is preferably made of a material having a high thermal conductivity in view of heat dissipation. Examples of the material having a high thermal conductivity include ceramics such as alumina and aluminum nitride, a highly thermally conductive resin, and a material in which a surface of a metal plate is coated with an insulating material. Further, the substrate 21 may have a single-layer structure or a multi-layer structure.

A wiring pattern may be provided on the surface of the substrate 21. The wiring pattern may be formed of a material containing silver as a main component, or may be formed of a material containing copper as a main component, for example.

At least one light emitting element 22 may be provided. In the light emitting module 20 illustrated in fig. 1 and 2, four light emitting elements 22 are provided. The number of light emitting elements 22 may be changed as appropriate depending on the application, size, and the like of the vehicle illumination device 1. When a plurality of light emitting elements 22 are provided, the plurality of light emitting elements 22 may be connected in series with each other. The light emitting element 22 may be connected in series to the resistor 23.

The light emitting element 22 may be provided on the opposite side of the substrate 21 from the heat transfer portion 40 side. The light emitting elements 22 may be electrically connected with the wiring patterns.

The light emitting element 22 may be, for example, a light emitting diode, an organic light emitting diode, a laser diode, or the like.

The light emitting element 22 may be a surface mount type light emitting element, a light emitting element with a lead such as a shell type light emitting element, a chip type light emitting element, or the like. The light-emitting element 22 illustrated in fig. 1 and 2 is a chip-shaped light-emitting element. In this case, a chip-shaped light-emitting element is preferably used as the light-emitting element 22 in view of downsizing of the light-emitting module 20. The Chip-like light-emitting element 22 can be packaged by COB (Chip On Board) technology. In this way, a plurality of light emitting elements 22 can be provided in a narrow area. Therefore, the light-emitting module 20 can be downsized, and the vehicle illumination device 1 can be downsized.

When the light-emitting element 22 is a chip-shaped light-emitting element, it may be any of a vertical electrode type light-emitting element, a top electrode type light-emitting element, and a flip chip type light-emitting element. The vertical geometry light emitting element and the upper geometry light emitting element may be electrically connected to the wiring pattern by wiring. The flip-chip type light emitting element may be directly mounted on the wiring pattern.

The number, size, arrangement, and the like of the plurality of light emitting elements 22 are not limited to the examples, and may be appropriately changed according to the size, the application, and the like of the vehicle illumination device 1.

The resistor 23 may be provided on the opposite side of the substrate 21 from the heat transfer portion 40 side. The resistor 23 may be provided with at least one. The resistor 23 may be electrically connected to the wiring pattern.

The resistor 23 may be a surface mount resistor, a resistor with lead (metal oxide film resistor), a film-like resistor formed by a screen printing method, or the like, for example. The resistor 23 illustrated in fig. 1 is a film-shaped resistor.

Ruthenium oxide (RuO) can be used as a material of the film-like resistor₂). For example, a film-like resistor can be formed by a screen printing method or a firing method. If the resistor 23 is a film-like resistor, the contact area between the resistor 23 and the substrate 21 can be increased, and thus the heat dissipation can be improved. Then, the plurality of resistors 23 can be formed by one process. Therefore, productivity can be improved. Further, variations in the resistance values of the plurality of resistors 23 can be suppressed.

Here, since the forward voltage characteristics of the light-emitting element 22 vary, the luminance (luminous flux, luminance, emission intensity, illuminance) of light emitted from the light-emitting element 22 varies when the applied voltage between the anode terminal and the ground terminal is constant. Therefore, the value of the current flowing through the light emitting element 22 is adjusted to fall within a predetermined range by the resistor 23, and the luminance of the light emitted from the light emitting element 22 falls within the predetermined range. At this time, by changing the resistance value of the resistor 23, the value of the current flowing through the light emitting element 22 can be controlled within a predetermined range.

When the resistor 23 is a film-like resistor, the resistance value can be increased by removing a part of the resistor 23. For example, by irradiating the resistor 23 with laser light, a part of the resistor 23 can be easily removed. When the resistor 23 is a surface-mount resistor, a resistor with lead, or the like, the resistor 23 having an appropriate resistance value may be selected in accordance with the forward voltage characteristic of the light-emitting element 22. The number, size, arrangement, and the like of the resistors 23 are not limited to the example, and the number, size, arrangement, and the like of the resistors 23 may be appropriately changed according to the number, specification, and the like of the light emitting elements 22.

The control element 24 may be provided on the opposite side of the substrate 21 from the heat transfer portion 40 side. At least one control element 24 may be provided. The control element 24 may be electrically connected with the wiring pattern. The control element 24 may be connected in series with the plurality of light emitting elements 22 and the resistor 23.

The control element 24 is provided to prevent reverse voltage from being applied to the light emitting element 22 and to prevent reverse impulse noise from being applied to the light emitting element 22. The control element 24 may be a diode, for example. The control element 24 may be, for example, a surface-mount diode, a diode with a lead, a chip-like diode, or the like. The control element 24 illustrated in fig. 1 is a surface-mount diode.

The capacitor 25 is provided, for example, for noise countermeasure and voltage smoothing. The capacitor 25 may be provided on the opposite side of the substrate 21 from the heat transfer portion 40 side. At least one capacitor 25 may be provided. The capacitor 25 may be electrically connected to the wiring pattern. The capacitor 25 may be connected in parallel with the light emitting element 22. The capacitor 25 may be a chip-like capacitor or a surface-mount type capacitor.

The frame 26 may be provided on the opposite side of the substrate 21 from the heat transfer portion 40 side. The frame 26 may be bonded to the substrate 21. In this case, the frame portion 26 may be bonded to the substrate 21 with an adhesive, or may be bonded to the substrate 21 with a part of the sealing portion 27 provided between the frame portion 26 and the substrate 21.

The frame 26 may have a frame shape. At least one light emitting element 22 may be provided in a region surrounded by the frame portion 26. For example, the frame portion 26 may surround the plurality of light emitting elements 22. The frame 26 may be formed of resin. Examples of the resin include thermoplastic resins such as PBT (polybutylene terephthalate/polybutylene terephthalate), PC (polycarbonate/polycarbonate), PET (polyethylene), Nylon (Nylon), PP (polypropylene/polypropylene), PE (polyethylene/polyethylene), and PS (polystyrene/polystyrene). The frame 26 can be formed by injection molding, for example.

The frame 26 may be formed of a resin containing particles of titanium oxide or the like, or may be formed of a white resin. In this way, the reflectance with respect to the light emitted from the light-emitting element 22 can be increased. The inner wall surface of the frame 26 may be an inclined surface inclined in a direction away from the central axis of the frame 26 as the substrate 21 is separated.

That is, the frame portion 26 may have a function of a mirror.

In addition, the case where the frame portion 26 is molded in advance and then the molded frame portion 26 is bonded to the substrate 21 has been described above. However, the frame portion 26 may be formed by supplying a softened resin onto the substrate 21 in a frame shape and curing the resin. For example, the frame portion 26 may be formed by supplying a resin softened by adding a solvent or the like or a resin softened by heating onto the substrate 21 in a ring shape and curing the resin. The supply of the softened resin may be performed by, for example, a dispenser or a hot-melt device.

Further, the frame 26 may be omitted. When the frame 26 is omitted, a dome-shaped sealing portion 27 covering the light emitting element 22 may be provided. However, the frame 26 can define the range of formation of the sealing portion 27. Therefore, the increase in the planar size of the sealing portion 27 can be suppressed, and therefore, the light-emitting module 20 and, in turn, the vehicle illumination device 1 can be downsized.

The sealing portion 27 may be provided inside the frame portion 26. The sealing portion 27 may cover an area surrounded by the frame portion 26. The sealing portion 27 covers the light emitting element 22. The sealing portion 27 has a function of protecting the chip-shaped light-emitting element 22. In the case where the light emitting element 22 is a surface-mount type light emitting element, a light emitting element with a lead wire such as a bullet type light emitting element, or the like, the frame portion 26 and the sealing portion 27 may be omitted.

The sealing portion 27 may be formed of a resin having light transmittance. The sealing portion 27 may be formed of, for example, silicone resin. The sealing portion 27 can be formed by filling a region surrounded by the frame portion 26 with a resin softened by adding a solvent or the like, for example. For filling the resin, for example, a dispenser or the like can be used. The sealing portion 27 may contain a phosphor. The phosphor may be, for example, a YAG phosphor (yttrium aluminum garnet phosphor). However, the kind of the fluorescent material may be appropriately changed so as to obtain a predetermined emission color according to the use of the vehicle lighting device 1 and the like.

The coating portion 28 may cover the wiring pattern and the film-like resistor 23. The coating portion 28 is provided to protect the wiring pattern and the film-like resistor 23. The covering 28 may be made of resin, glass material, or the like.

The power supply portion 30 may have a plurality of power supply terminals 31 and an insulating portion 32.

The plurality of power supply terminals 31 may be rod-shaped bodies. The plurality of power supply terminals 31 may protrude from the bottom surface 11a1 of the recess 11 a. The plurality of power supply terminals 31 may be arranged in a predetermined direction. The plurality of power supply terminals 31 are provided inside the insulating portion 32. The ends of the power supply terminals 31 on the light-emitting module 20 side are soldered to the wiring pattern. The ends of the plurality of power supply terminals 31 on the heat sink 14 side are exposed to the inside of the connector holder 15. The connector 105 may be fitted to the plurality of power supply terminals 31 exposed to the inside of the connector holder 15. The plurality of power supply terminals 31 have conductivity. The plurality of power supply terminals 31 may be made of metal such as copper alloy, for example. The number, shape, arrangement, material, and the like of the plurality of power supply terminals 31 are not limited to the examples, and may be appropriately changed.

The highly thermally conductive resin as the material of the lamp socket 10 may have electrical conductivity. For example, a highly thermally conductive resin using a filler containing carbon has electrical conductivity. Therefore, in order to ensure insulation between the power supply terminal 31 and the conductive lamp socket 10, an insulating portion 32 is provided. The insulating portion 32 also has a function of holding the plurality of power supply terminals 31. In the case where the socket 10 is made of an insulating highly thermally conductive resin (for example, a highly thermally conductive resin containing a filler made of ceramic or the like is used), the insulating portion 32 may be omitted. At this time, the plurality of power supply terminals 31 are held by the lamp socket 10.

The insulating portion 32 may be made of resin having insulating properties. The insulating portion 32 may be formed of, for example, PET or nylon. The insulating portion 32 may be press-fitted into a hole provided in the socket 10, bonded to the inside of the hole, or clad to the inside of the hole, for example.

The heat transfer portion 40 may be disposed between the mounting portion 11 and the light emitting module 20. The heat transfer portion 40 is preferably made of a material having a high thermal conductivity. The heat transfer portion 40 may be made of metal such as aluminum, aluminum alloy, copper alloy, or the like. The heat transfer portion 40 may be adhered to the bottom surface 11a1 of the recess 11 a. In this case, the same adhesive as that used to bond the substrate 21 to the surface 40a of the heat transfer portion 40 may be used. The heat transfer unit 40 may be attached to the bottom surface 11a1 of the recess 11a via a layer containing heat conductive silicone grease. As the heat conductive silicone grease, for example, a heat conductive silicone grease obtained by mixing a filler made of an inorganic material with modified silicone oil can be used. Heat transfer portion 40 may be embedded in bottom surface 11a1 of recess 11a by insert molding or the like.

In addition, when the heat generated in the light emitting module 20 is small, the heat transfer portion 40 may be omitted. However, in recent years, the brightness of light emitted from the light emitting element 22 is expected to be brighter, and therefore, the electric power applied to the light emitting module 20 may be 2.5 watts or more.

In this case, since the amount of heat generated in the light emitting module 20 increases, it is preferable to provide the heat transfer portion 40 and form the socket 10 using a high thermal conductive resin having a thermal conductivity of 15 watts/(m · K) or more. The thermal conductivity of the high thermal conductive resin may be adjusted according to the content of the filler. For example, if the content of the filler is increased, the thermal conductivity can be increased.

However, if the content of the filler becomes large, the highly thermally conductive resin becomes brittle. Further, as described above, if the outer diameter a1 of the flange 13 is made small to make the vehicle lighting device 1 smaller and lighter, the force required to be applied to the heat sink 14 when the vehicle lighting device 1 is mounted becomes large. Therefore, if the content of the filler is excessively increased in order to increase the thermal conductivity, the heat dissipation sheet 14 is easily broken.

According to the findings of the present inventors, when the electric power applied to the light emitting module 20 is 2.5 watts or more and 5.5 watts or less, it is preferable to provide the heat transfer portion 40 and use the lamp socket 10 containing the high thermal conductive resin having the thermal conductivity of 15 watts/(m · K) or more and 25 watts/(m · K) or less. In this way, the temperature of the light emitting element 22 can be suppressed from exceeding the maximum PN junction temperature, and the heat sink 14 can be suppressed from being damaged.

The present inventors have also found that, when the outer diameter a2 of the mounting portion 11 is set to 19mm or less in order to reduce the size and weight of the vehicle lighting device 1, the difference between the outer diameter a1 of the flange 13 and the outer diameter a2 of the mounting portion 11 affects the heat dissipation of the socket 10.

Fig. 3 is a table for illustrating the influence of the difference between the outer diameter a1(mm) of the flange 13 and the outer diameter a2(mm) of the mounting portion 11 on the heat dissipation performance and the reduction in size and weight of the lamp socket 10.

Fig. 3 shows a case where the applied electric power W is set to 2.5 watts or more and 5.5 watts or less, the thermal conductivity WT of the high thermal conductive resin is set to 15 watts/(m · K) or more and 25 watts/(m · K) or less, and the outer diameter a2 of the mounting portion 11 is set to 19mm or less. Further, a heat transfer portion 40 is provided. In addition, "saturation" in fig. 3 means that heat dissipation cannot be further improved.

As is clear from fig. 3, if "40 (1/K) ≦ (a1-a2) × WT/W ≦ 90 (1/K)", the heat dissipation of the lamp socket 10 can be improved and the lamp socket 10 can be made smaller and lighter.

Further, if the length of the heat radiating fins 14 in the direction along the central axis 1a of the vehicle lighting device 1 is increased, the heat radiating area can be increased, and thus the heat radiating performance of the socket 10 can be improved. However, it was confirmed that the heat radiation performance could not be further improved even if the length of the heat radiation fins 14 was increased.

Fig. 4 is a table illustrating the influence of the length of the heat sink 14 on the heat dissipation of the socket 10 and the reduction in size and weight.

The dimension b (mm) in fig. 4 is a dimension between the light emitting surface (upper surface) of the light emitting element 22 and the end surface of the heat sink 14 on the side opposite to the flange 13 side in the direction along the central axis 1a of the vehicle illumination device 1.

Fig. 4 shows a case where the applied electric power W is set to 2.5 watts or more and 5.5 watts or less, the thermal conductivity WT of the high thermal conductive resin is set to 15 watts/(m · K) or more and 25 watts/(m · K) or less, and the outer diameter a2 of the mounting portion 11 is set to 19mm or less. Further, a heat transfer portion 40 is provided. In addition, "saturation" in fig. 4 means that heat dissipation cannot be further improved.

As can be seen from fig. 4, the longer the dimension B, the higher the heat dissipation. However, if the dimension B is 31mm or more, the heat dissipation performance cannot be further improved, and conversely, the lamp socket 10 becomes larger and heavier due to the longer dimension B.

Therefore, as can be seen from FIG. 4, it is preferable to set "25 mm. ltoreq. B.ltoreq.30 mm".

(vehicle lamp)

Next, the vehicle lamp 100 is exemplified.

In the following, a case where the vehicle lamp 100 is a front combination lamp provided in an automobile will be described as an example. However, the vehicle lamp 100 is not limited to a front combination lamp provided in an automobile. The vehicle lamp 100 may be any vehicle lamp provided in an automobile, a rail vehicle, or the like.

Fig. 5 is a partially schematic sectional view for illustrating the vehicular lamp 100.

As shown in fig. 5, the vehicle lamp 100 may be provided with a vehicle lighting device 1, a housing 101, a cover 102, an optical element portion 103, a sealing member 104, and a connector 105.

The frame 101 holds the mounting portion 11. The frame 101 has a box shape with one end open. The frame 101 may be made of, for example, a resin that does not transmit light. A mounting hole 101a into which a portion of the mounting portion 11 where the engagement pin 12 is provided is inserted is provided in the bottom surface of the frame 101. A recess into which engagement pin 12 provided in mounting portion 11 is inserted is provided at the periphery of mounting hole 101 a. Although the case where the mounting hole 101a is directly provided in the housing 101 is described here as an example, a mounting member having the mounting hole 101a may be provided in the housing 101.

When the vehicle lighting device 1 is mounted on the vehicle lamp 100, the portion of the mounting portion 11 where the engagement pin 12 is provided is inserted into the mounting hole 101a, and the vehicle lighting device 1 is rotated. In this way, the engaging pin 12 is held in the fitting portion provided at the peripheral edge of the mounting hole 101 a. This method of installation is known as twist-locking.

The cover 102 is provided to cover the opening of the frame 101. The cover 102 may be made of a resin or the like having light transmittance. The cover 102 may also have a function of a lens or the like.

The light emitted from the vehicle lighting device 1 enters the optical element unit 103. The optical element unit 103 reflects, diffuses, guides, and condenses light emitted from the vehicle illumination device 1, and forms a predetermined light distribution pattern or the like. For example, the optical element 103 illustrated in fig. 5 is a mirror. At this time, the optical element portion 103 reflects the light emitted from the vehicle illumination device 1 to form a predetermined light distribution pattern.

The sealing member 104 may be provided between the flange 13 and the frame 101. The sealing member 104 may be annular. The sealing member 104 may be made of a material having elasticity such as rubber or silicone resin.

When the vehicle lighting device 1 is mounted on the vehicle lamp 100, the sealing member 104 is sandwiched between the flange 13 and the housing 101. Therefore, the internal space of the housing 101 can be sealed by the sealing member 104. Then, the engaging pin 12 is pressed against the housing 101 by the elastic force of the seal member 104. Therefore, the vehicle lighting device 1 can be prevented from falling off the housing 101.

The connector 105 is fitted to the end portions of the plurality of power supply terminals 31 exposed inside the connector holder 15. A power supply and the like, not shown, may be electrically connected to the connector 105. Therefore, by fitting the connector 105 to the end portions of the plurality of power supply terminals 31, a power supply or the like, not shown, can be electrically connected to the light emitting element 22.

In addition, the connector 105 is provided with a seal member 105 a. The sealing member 105a is provided for the purpose of preventing moisture from entering the inside of the connector housing 15. 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 watertight.

While several embodiments of the present invention have been described above, these embodiments are merely illustrative and are not intended to limit the scope of the present invention. These new embodiments can be implemented in other various forms, and various omissions, substitutions, and changes can be made without departing from the spirit of the present invention. These embodiments and modifications thereof are within the scope and spirit of the present invention, and are also included in the invention described in the claims and equivalents thereof. The above embodiments may be combined with each other.