JP6233560B2 - VEHICLE LIGHTING DEVICE AND VEHICLE LIGHT - Google Patents

Description

Embodiments described below generally, vehicle lighting apparatus, and a vehicle lamp.

A substrate, a plurality of light emitting diodes (LEDs) mounted on the substrate, a surrounding wall member bonded on the substrate so as to surround the plurality of light emitting diodes, and a filling inside the surrounding wall member There is a lighting device provided with a sealed portion.
In such an illuminating device, when a substrate made of ceramics is used, there is a problem that the fixing strength (adhesion strength) between the surrounding wall member and the substrate is lowered.
When the fixing strength between the surrounding wall member and the substrate is lowered, a portion that is partially weak against external stress and thermal shock is formed. For this reason, the airtightness between the surrounding wall member and the substrate is lowered, and there is a possibility that performance degradation due to intrusion of moisture / gas, poor conduction due to peeling of the sealing portion, and the like may occur. Thus, there has been a demand for the development of a lighting device that can improve the adhesion strength between the surrounding wall member and the substrate even when a substrate made of ceramics is used.

JP 2013-25935 A

An object of the present invention is to provide, surrounding wall member and the vehicle lighting device capable of improving the adhesion strength between the substrate and to provide a vehicle lamp.

An illumination device for a vehicle according to an embodiment includes: a substrate including ceramics at least on a surface thereof; a wiring pattern provided on the surface of the substrate ; a light emitting element provided on the wiring pattern ; and surrounding the light emitting element. in the region where the surrounding wall member is provided, and the substrate, wherein a surrounding wall member, a junction provided between; to the surrounding wall member and disposed in a region where the surrounding wall member is provided, wherein A covering portion that is provided between the substrate and the bonding portion and includes a glass material; and the covering portion is in contact with the surface of the substrate, the surface of the wiring pattern, and the bonding portion; The joint is in contact with the surrounding wall member .

According to an embodiment of the present invention, it is possible to provide a surrounding wall member and the vehicle lighting device capable of improving the adhesion strength between the substrate and the vehicle lighting device.

It is a schematic perspective view for illustrating the illuminating device 1 which concerns on this Embodiment. It is a schematic perspective view for illustrating the illuminating device 1 which concerns on this Embodiment. 3 is a schematic plan view of a light emitting unit 20. FIG. It is the sectional view on the AA line in FIG. It is a schematic cross section for illustrating the case where the coating | coated part 29 is not provided. It is a schematic cross section for illustrating the case where the coating | coated part 29 is provided.

The invention according to the embodiment includes a substrate containing ceramics at least on a surface; a wiring pattern provided on the surface of the substrate ; a light emitting element provided on the wiring pattern ; and surrounding the light emitting element. A surrounding wall member; in a region where the surrounding wall member is provided , a joint provided between the substrate and the surrounding wall member; in a region where the surrounding wall member is provided ; And a covering portion that includes a glass material, and the covering portion is in contact with the surface of the substrate, the surface of the wiring pattern, and the bonding portion, and the bonding portion. Is a vehicle lighting device in contact with the surrounding wall member .
According to this vehicle lighting device, the fixing strength between the surrounding wall member and the substrate can be improved.

Hereinafter, embodiments will be illustrated with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.
1 and 2 are schematic perspective views for illustrating the lighting device 1 according to the present embodiment.
FIG. 1 is a schematic perspective view of the lighting device 1, and FIG. 2 is a schematic exploded view of the lighting device 1.
FIG. 3 is a schematic plan view of the light emitting unit 20.
4 is a cross-sectional view taken along line AA in FIG.

As shown in FIGS. 1 and 2, the lighting device 1 is provided with a main body 10, a light emitting unit 20, a power feeding unit 30, and a socket 40.
The main body portion 10 is provided with a storage portion 11, a flange portion 12, and fins 13. The storage portion 11 has a cylindrical shape and protrudes from one surface of the flange portion 12. A light emitting unit 20 is stored inside the storage unit 11. Further, the power supply terminal 31 of the power supply unit 30 protrudes inside the storage unit 11.

The flange portion 12 has a disk shape, and the storage portion 11 is provided on one surface, and the fins 13 are provided on the other surface.
A plurality of fins 13 are provided so as to protrude from the surface of the flange portion 12. The plurality of fins 13 have a plate shape and function as heat radiating fins.

The main body unit 10 has a function of housing the light emitting unit 20 and the power feeding unit 30 and the like, and a function of releasing heat generated in the light emitting unit 20 and the power feeding unit 30 to the outside of the lighting device 1.
Therefore, the main body 10 can be formed from a material having high thermal conductivity in consideration of releasing heat to the outside. For example, the main body 10 can be formed from aluminum, an aluminum alloy, a high thermal conductivity resin, or the like. The high thermal conductive resin is, for example, a resin such as PET or nylon mixed with fibers or particles such as carbon or aluminum oxide having high thermal conductivity.
In this case, a portion such as the fin 13 that discharges heat to the outside can be formed from a material having high thermal conductivity, and the other portion can be formed from a resin or the like.
In the case where the main part of the main body 10 is made of a conductive material, the periphery of the power supply terminal 31 is made of an insulating material (to ensure electrical insulation between the power supply terminal 31 and the conductive material of the main body 10. (Not shown), and a conductive material may be disposed around the cover. The insulating material is preferably a material having high thermal conductivity such as resin. Further, the main body 10 may be provided with an attaching part that can be attached to and detached from the vehicular lamp.

As shown in FIGS. 3 and 4, the light emitting unit 20 includes a substrate 21, a light emitting element 22, a control element 23, a wiring pattern 24, a wiring 25, an enclosing wall member 26, a sealing part 27, a bonding part 28, and a cover. A portion 29 is provided.
The substrate 21 is provided inside the storage unit 11 of the main body unit 10.
The substrate 21 has a plate shape, and a wiring pattern 24 is provided on the surface.
The substrate 21 can be made of a ceramic such as aluminum oxide or aluminum nitride.
Moreover, the board | substrate 21 may coat | cover the surface of a metal plate with ceramics.
That is, the substrate 21 only needs to include ceramics at least on its surface.

If the substrate 21 is formed using such a material, the heat generated in the light emitting element 22 can be efficiently released through the substrate 21 and the main body 10.
The substrate 21 may be a single layer or a multilayer.

A plurality of light emitting elements 22 are mounted on a wiring pattern 24 provided on the surface of the substrate 21.
The light emitting element 22 may have an electrode (not shown) on the surface (upper surface) opposite to the side provided on the wiring pattern 24. The electrodes (not shown) may be provided on the surface (lower surface) provided on the wiring pattern 24 and on the surface (upper surface) opposite to the side provided on the wiring pattern 24. It may be provided only on the surface.

  The electrode provided on the lower surface of the light emitting element 22 is electrically connected to the mounting pad 24b provided on the wiring pattern 24 through a conductive thermosetting material such as silver paste. An electrode (not shown) provided on the upper surface of the light emitting element 22 is electrically connected to a wiring pad 24 c provided on the wiring pattern 24 via a wiring 25.

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 upper surface, which is the light emission surface of the light emitting element 22, is directed to the front side of the lighting device 1, and mainly emits light toward the front side of the lighting device 1.
The number, size, and the like of the light emitting elements 22 are not limited to those illustrated, and can be appropriately changed according to the size, use, and the like of the lighting device 1.

The control element 23 is mounted on the wiring pattern 24.
The control element 23 controls the current flowing through the light emitting element 22. That is, the control element 23 controls the light emission of the light emitting element 22.
The number and size of the control elements 23 are not limited to those illustrated, and can be appropriately changed according to the number and specifications of the light emitting elements 22.

The wiring pattern 24 is provided on at least one surface of the substrate 21.
The wiring pattern 24 can be provided on both surfaces of the substrate 21, but it is preferable to provide the wiring pattern 24 on one surface of the substrate 21 in order to reduce the manufacturing cost.
The wiring pattern 24 is provided with an input terminal 24a.
A plurality of input terminals 24a are provided. The power supply terminal 31 of the power supply unit 30 is electrically connected to the input terminal 24a. Therefore, the light emitting element 22 is electrically connected to the power feeding unit 30 via the wiring pattern 24.

The wiring 25 electrically connects an electrode (not shown) provided on the upper surface of the light emitting element 22 and a wiring pad 24 c provided on the wiring pattern 24.
The wiring 25 can be, for example, a wire whose main component is gold. However, the material of the wiring 25 is not limited to a material mainly composed of gold, and may be a material mainly composed of copper, a material mainly composed of aluminum, or the like.

  The wiring 25 is electrically connected to an electrode (not shown) provided on the upper surface of the light emitting element 22 and a wiring pad 24c provided on the wiring pattern 24 by, for example, ultrasonic welding or heat welding. The wiring 25 can be electrically connected to an electrode (not shown) provided on the upper surface of the light emitting element 22 and a wiring pad 24 c provided on the wiring pattern 24 by using, for example, a wire bonding method.

  In addition, circuit components (not shown) can be provided as necessary. A circuit component (not shown) can be mounted on the wiring pattern 24, for example.

The surrounding wall member 26 is provided on the substrate 21 so as to surround the plurality of light emitting elements 22. The surrounding wall member 26 has, for example, an annular shape, and the plurality of light emitting elements 22 are exposed at the central portion 26a. In addition, the shape of the surrounding wall member 26 may be an elliptical shape or a polygonal shape such as a quadrangle, a hexagon, or an octagon, and is not particularly limited to the shape.
The surrounding wall member 26 can be formed from resin, for example. In this case, the surrounding wall member 26 is preferably formed of, for example, polyamide (polyamide) resin or PBT (polybutylene terephthalate).
In addition, the reflectance of the light emitted from the light emitting element 22 can be improved by mixing particles such as titanium oxide in the resin.
Note that the particles are not limited to titanium oxide particles, and particles made of a material having a high reflectance with respect to light emitted from the light emitting element 22 may be mixed.
Moreover, the surrounding wall member 26 can also be formed from white resin, for example.

The side wall surface 26b on the central portion 26a side of the surrounding wall member 26 is an inclined surface. A part of the light emitted from the light emitting element 22 is reflected by the side wall surface 26 b of the surrounding wall member 26 and emitted toward the front side of the lighting device 1.
Further, a part of the light emitted from the light emitting element 22 toward the front side of the lighting device 1 and totally reflected by the top surface of the sealing portion 27 (interface between the sealing portion 27 and the outside air) The light is reflected by the side wall surface 26b on the side of the central portion 26a of the surrounding wall member 26 and irradiated again toward the front side of the lighting device 1.

  That is, the surrounding wall member 26 can also have the function of a reflector. In addition, the form of the surrounding wall member 26 is not necessarily limited to what was illustrated, and can be changed suitably.

The sealing portion 27 is provided at the central portion 26 a of the surrounding wall member 26. The sealing portion 27 is provided so as to cover the inner side of the surrounding wall member 26.
The sealing portion 27 is formed from a light-transmitting material. The sealing part 27 can be formed from, for example, a silicone resin.
The sealing portion 27 can be formed, for example, by filling the central portion 26a of the surrounding wall member 26 with resin. The filling of the resin can be performed using, for example, a liquid dispensing apparatus such as a dispenser.

  If the central portion 26a of the surrounding wall member 26 is filled with resin, mechanical contact from the outside to the light emitting element 22, the wiring pattern 24 exposed to the central portion 26a of the surrounding wall member 26, the wiring 25, and the like is suppressed. Can do. Moreover, it can suppress that air, a water | moisture content, etc. adhere to the wiring pattern 24 exposed to the light emitting element 22, the center part 26a of the surrounding wall member 26, the wiring 25, etc. FIG. Therefore, the reliability with respect to the illuminating device 1 can be improved.

Further, the sealing portion 27 can include a phosphor. The phosphor may be, for example, a YAG phosphor (yttrium / aluminum / garnet phosphor).
For example, when the light emitting element 22 is a blue light emitting diode and the phosphor is a YAG phosphor, the YAG phosphor is excited by the blue light emitted from the light emitting element 22, and yellow fluorescence is emitted from the YAG phosphor. Radiated. Then, the blue light and the yellow light are mixed, whereby white light is emitted from the lighting device 1. In addition, the kind of fluorescent substance and the kind of light emitting element 22 are not necessarily limited to what was illustrated, and can be suitably changed according to the use of the illuminating device 1, etc. so that a desired luminescent color may be obtained.

The joining portion 28 joins the surrounding wall member 26 and the substrate 21 via the covering portion 29.
The joining portion 28 has a film shape and is provided between the surrounding wall member 26 and the covering portion 29. The joining portion 28 can be formed, for example, by curing a silicone adhesive or an epoxy adhesive.

The joint portion 28 can be formed by the following procedure, for example.
First, a silicone-based adhesive or an epoxy-based adhesive is applied on the covering portion 29.
For example, an adhesive is applied on the covering portion 29 using a dispenser or the like.
Next, the adhesive is cured by evaporating the solvent and the like to form the joint portion 28, and the surrounding wall member 26 and the substrate 21 are joined via the covering portion 29.
For example, first, the surrounding wall member 26 is placed on the applied adhesive.
Subsequently, the surrounding wall member 26 is pressed to bring the adhesive into close contact with the surrounding wall member 26 and the position of the surrounding wall member 26 (adhesive thickness) is adjusted.
Thereafter, the adhesive is cured by evaporating the solvent.

Here, the viscosity of the adhesive before curing is preferably 1 Pa · s to 15 Pa · s. With such a viscosity, when applying using a dispenser or the like, it becomes easy to apply in an arbitrary shape.
In addition, with such a viscosity, the position of the surrounding wall member 26 can be stabilized when the adhesive is cured.

Moreover, when the illuminating device 1 is a vehicle-mounted illuminating device, the junction part 28 needs to have high reliability in a wide temperature range.
For example, in the case of an in-vehicle lighting device, a temperature change in the range of −40 ° C. to + 85 ° C. is repeated at regular intervals, or is affected by heat due to lighting of the light emitting element 22. Therefore, expansion and contraction occur in the surrounding wall member 26, the joint portion 28, and the substrate 21.

In this case, when the substrate 21 is formed of ceramics, the linear expansion coefficient is about 7 ppm / K. When the surrounding wall member 26 is formed of resin, the linear expansion coefficient is about 20 ppm / K to 250 ppm / K. Therefore, thermal stress is generated due to the difference in linear expansion coefficient.
Here, in order to relieve the thermal stress, the value of the linear expansion coefficient of the joint portion 28 is larger than the value of the linear expansion coefficient of the substrate 21 and smaller than the value of the linear expansion coefficient of the surrounding wall member 26. can do.

For example, the linear expansion coefficient of polyamide (polyamide) resin or PBT (polybutylene terephthalate), which is a material of the surrounding wall member 26, is about 80 ppm / K to 90 ppm / K. The linear expansion coefficient of the ceramic material that is the material of the substrate 21 is about 7 ppm / K. And the junction part 28 is formed using an epoxy-type adhesive agent (linear expansion coefficient 60ppm / K).
As described above, when the joint portion 28 is formed using an epoxy adhesive so that the linear expansion coefficient is between the surrounding wall member 26 and the substrate 21, the thermal stress can be reduced.
However, if the bonding portion 28 is formed using an epoxy adhesive, the elasticity may be small and thermal stress may not be sufficiently relaxed.

If the thermal stress cannot be sufficiently relaxed even when an epoxy adhesive is used, the elasticity of the joint 28 may be increased.
For example, the joint portion 28 can be formed using a silicone-based adhesive. That is, the joining portion 28 can include a silicone resin.
In this case, when the joint portion 28 is formed using a silicone-based adhesive, the linear expansion coefficient of the joint portion 28 is about 200 ppm / K.

However, although the joint portion 28 formed using a silicone-based adhesive has a high coefficient of linear expansion, it has high elasticity and can absorb the amount of expansion and contraction that accompanies a change in temperature. Therefore, the thermal stress can be sufficiently relaxed.
Further, if the joint portion 28 is formed using a silicone-based adhesive, the surrounding wall member 26 must be formed using a material having a high linear expansion coefficient (for example, a material having a coefficient of 200 ppm / K to 250 ppm / K). Even so, thermal stress can be relaxed.

The covering portion 29 is provided between the substrate 21 and the joining portion 28.
The covering portion 29 is provided in order to improve the adhesion strength between the surrounding wall member 26 and the substrate 21.
The coating | coated part 29 shall contain a glass material.
Details regarding the covering portion 29 will be described later.

The power feeding unit 30 is provided with a plurality of power feeding terminals 31.
The plurality of power supply terminals 31 extend inside the storage portion 11 and the flange portion 12. One end portion of the plurality of power supply terminals 31 protrudes from the bottom surface of the storage portion 11 and is electrically connected to the input terminal 24 a of the wiring pattern 24. The other ends of the plurality of power supply terminals 31 are exposed from the side opposite to the side on which the substrate 21 of the main body 10 is provided.

In addition, the number, arrangement | positioning, form, etc. of the electric power feeding terminal 31 are not necessarily limited to what was illustrated, and can be changed suitably.
The power feeding unit 30 may include a substrate (not shown) and circuit components such as a capacitor and a resistor. In addition, the board | substrate and circuit component which are not shown in figure can be provided in the inside of the accommodating part 11 or the flange part 12, for example.

The socket 40 is fitted to the ends of the plurality of power supply terminals 31 exposed on the side opposite to the side on which the substrate 21 of the main body 10 is provided.
The socket 40 is electrically connected to a power source (not shown).
Therefore, by fitting the socket 40 to the end of the power supply terminal 31, the power source (not shown) and the light emitting element 22 are electrically connected.
The socket 40 can be bonded to the element on the main body 10 side using, for example, an adhesive.

Next, the covering portion 29 will be further described.
FIG. 5 is a schematic cross-sectional view for illustrating a case where the covering portion 29 is not provided.
FIG. 6 is a schematic cross-sectional view for illustrating the case where the covering portion 29 is provided.
As shown in FIG. 5, when the covering portion 29 is not provided, the bonding portion 28 is provided on the surface of the substrate 21.

  Here, the light emitting element 22 and the control element 23 are mounted on the surface of the substrate 21. Therefore, the flatness of the substrate 21 needs to be increased. In general, the center line average roughness Ra of the surface of the substrate 21 is set to 0.3 μm or less.

  However, the substrate 21 made of ceramics is porous and has fine irregularities on the surface. For this reason, the adhesive may not sufficiently enter the inside of the fine uneven portion, and a gap may be formed between the surface of the substrate 21 and the bonding portion 28 as shown in B portion in FIG. is there. When a gap is formed between the surface of the substrate 21 and the joint portion 28, when an external force is applied, peeling is likely to occur starting from the gap. As a result, the adhesion strength between the surrounding wall member 26 and the substrate 21 may be lowered.

On the other hand, there are no fine uneven portions on the surface of the covering portion 29 formed of the glass material.
Therefore, as shown in FIG. 6, the formation of a gap between the surface of the covering portion 29 and the joint portion 28 can be suppressed. As a result, even if an external force is applied, peeling hardly occurs, so that the fixing strength between the surrounding wall member 26 and the substrate 21 can be improved.
Further, if the center line average roughness Ra of the surface of the covering portion 29 exceeds 0.3 μm, the contact area between the surface of the covering portion 29 and the joint portion 28 can be increased. The fixing strength between the member 26 and the substrate 21 can be further improved.

If the adhesion strength between the surrounding wall member 26 and the substrate 21 can be improved, the necessary adhesion strength can be ensured even if the size of the surrounding wall member 26 is reduced (even if the wall thickness is shortened). can do.
Therefore, the lighting device 1 can be downsized.

Such a covering portion 29 can be formed as follows, for example.
First, a glass paste is created.
The glass paste can include, for example, glass powder, a filler, and an organic solvent.

The glass powder can contain, for example, silicon, barium, calcium, bismuth, and the like.
The filler can include, for example, aluminum oxide.

The organic solvent can be, for example, toluene, xylene and the like.
The glass paste may further contain a pigment (white).
In addition, by controlling the particle size of the glass powder or filler contained in the glass paste, the viscosity of the glass paste, and the like, the center line average roughness Ra of the surface of the covering portion 29 should exceed 0.3 μm. Can do.

Next, a glass paste is applied to a region on the surface of the substrate 21 where the surrounding wall member 26 is provided by using a screen printing method or the like.
Next, the coating part 29 is formed by baking the glass paste.
As described above, the covering portion 29 having a surface centerline average roughness Ra exceeding 0.3 μm is formed on the substrate 21.

The covering portion 29 can be provided so as to cover the inner side of the surrounding wall member 26.
As described above, the sealing portion 27 can be formed by filling the central portion 26a of the surrounding wall member 26 with a silicone resin or the like.
Therefore, if the covering portion 29 is provided so as to cover the inner side of the surrounding wall member 26, the fixing strength between the sealing portion 27 and the substrate 21 can be improved.
If the fixing strength between the sealing portion 27 and the substrate 21 can be improved, the airtightness can be improved, the performance deterioration due to the ingress of moisture / gas can be suppressed, and the occurrence of poor conduction due to the peeling of the sealing portion 27 can be suppressed. Can be planned.
Further, if the fixing strength between the sealing portion 27 and the substrate 21 can be improved, the fixing between the surrounding wall member 26 and the substrate 21 can be reinforced.

Moreover, since the coating | coated part 29 is formed from a glass material, it has insulation.
Therefore, the covering portion 29 may be provided so as to cover the wiring pattern 24. If the wiring pattern 24 is covered by the insulating covering portion 29, the reliability of the lighting device 1 can be improved.

When the covering portion 29 is provided so as to cover the inside of the surrounding wall member 26 and the wiring pattern 24 as well, the area where the surrounding wall member 26 is provided, the inside of the surrounding wall member 26, using screen printing or the like. The covering portion 29 may be formed so as to cover the wiring pattern 24.
At this time, the covering portion 29 is not formed on the input terminal 24a, the mounting pad 24b, and the wiring pad 24c.

  As mentioned above, although several embodiment of this invention was illustrated, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, changes, and the like can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and equivalents thereof. Further, the above-described embodiments can be implemented in combination with each other.

  DESCRIPTION OF SYMBOLS 1 Illuminating device, 10 main-body part, 11 accommodating part, 20 light emission part, 21 board | substrate, 22 light emitting element, 23 control element, 24 wiring pattern, 25 wiring, 26 surrounding wall member, 26a center part, 27 sealing part, 28 joining Part, 29 covering part, 30 power feeding part, 40 socket

Claims (12)

A substrate containing ceramics at least on the surface;
A wiring pattern provided on the surface of the substrate;
A light emitting device provided on the wiring pattern ;
An enclosing wall member provided so as to surround the light emitting element;
A joint provided between the substrate and the surrounding wall member in a region where the surrounding wall member is provided ;
A covering portion provided between the substrate and the bonding portion and including a glass material in a region where the surrounding wall member is provided ;
Equipped with,
The covering portion is in contact with the surface of the substrate, the surface of the wiring pattern, and the bonding portion,
The joint portion is a vehicle lighting device in contact with the surrounding wall member . The vehicle lighting device according to claim 1, wherein a center line average roughness of a surface of the covering portion exceeds 0.3 μm. The vehicle lighting device according to claim 1, wherein a center line average roughness of a surface of the covering portion is larger than a center line average roughness of the substrate. The vehicular lighting device according to claim 1, wherein the joint includes a silicone resin. 5. The vehicular illumination device according to claim 1, wherein a linear expansion coefficient of the joint portion is larger than a linear expansion coefficient of the substrate and smaller than a linear expansion coefficient of the surrounding wall member.   The vehicle lighting device according to claim 1, further comprising a sealing portion provided at a central portion of the surrounding wall member.   The vehicle illumination device according to claim 6, wherein the covering portion is further provided inside the surrounding wall member and is in contact with the sealing portion.   The vehicle lighting device according to claim 1, further comprising a main body portion on which the substrate is provided.   The vehicular lighting device according to claim 8, wherein the main body has fins.   The vehicle lighting device according to claim 8, wherein the main body portion includes a high thermal conductive resin. Before SL wiring pattern electrically connected to the feeding terminal;
A socket mated with the power supply terminal;
The vehicle lighting device according to claim 1, further comprising: A vehicular lamp comprising the vehicular illumination device according to any one of claims 1 to 11 .

Images