JP2555493Y2 - Vehicle lighting - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular lamp using a large number of light emitting diodes or LED chips as light sources (hereinafter collectively referred to as LEDs).

[0002]

2. Description of the Related Art Conventionally, in a vehicular lamp such as a tail lamp, a turn signal lamp, a high mount stop lamp, etc., the LED has a longer life, has a remarkably small amount of heat generation and power consumption, and has a high luminous efficiency as compared with a light bulb. Has many advantages, such as being thinner and smaller, and being easily mounted on a vehicle body. Various proposals have been made for a light source using a module type LED having a large number of LEDs mounted on an insulating substrate. (Examples: Japanese Patent Application Laid-Open No. 61-183006, Japanese Patent Application No. 1-146376, Japanese Utility Model Publication No. 2-4404, etc.). 4 to 6 show such a module type L
FIG. 1 schematically shows a conventional example of a vehicular lamp using an ED. A lamp body 1 is formed in a flat plate shape of aluminum or the like. A lamp body 2 is provided on a front surface of the lamp body 1 and a lamp is provided together with the lamp body 1. The front lens 4 forming the chamber 3 is a module type LED arranged in a required number on the front surface of the lamp body 1 via the insulating sheet 5.

The module type LED 4 is formed by printing and forming a conductive pattern 7 for forming a predetermined electric circuit on an insulating substrate 6 made of stainless steel, ceramics, resin or the like.
For example, eight optical reflection recesses 9 for housing the EDs 8 are formed in two horizontal rows, and the conductive patterns 7 and the LEDs 8 are connected in series by bonding wires 10 for each row.
A transparent thermosetting resin layer (hereinafter abbreviated as transparent resin) 11 such as an epoxy resin is formed on the entire surface of the insulating substrate 6 to protect the ED 8 from moisture and the like, and is transparent to improve the light distribution characteristics of the lamp. The convex lens portion 12 is integrally formed on the surface of the resin 11 at a portion corresponding to each LED 8 by swelling. Then, such module type LEDs 4 are arranged and connected in two rows vertically and five rows horizontally, and the LEDs 8 in each row are connected in parallel to a power supply via a current control resistor 13 to constitute a vehicle lamp. The lamp is connected to a power source (battery) via a diode 14 for preventing reverse current. 15a and 15b are module type LEDs
Reference numeral 4 denotes an electrode, 16 denotes a set screw for fixing the module type LED 4 to the lamp body 1, and 17 denotes a set screw for fixing the front lens 2 to the lamp body 1.

The transparent resin 11 is provided on the inner surface of the front lens 2.
A plurality of lens steps 18 made of a convex lens are integrally formed corresponding to each of the convex lens portions 12.

When assembling a vehicle lamp using such a module type LED 4, first, a predetermined number of the module type LEDs 4 are electrically and mechanically connected and arranged on the lamp body 1 via an insulating sheet 5. After fixing to the lamp body 1 by the set screw 16, the rear opening of the front lens 2 is fitted to the outer periphery of the lamp body 1 and fixed to the lamp body 1 by the set screw 17 to complete the assembling operation.

[0006]

By the way, in the above-mentioned vehicular lamp using the LED 8 as a light source, the LE in the case where the power supply is erroneously connected positively and negatively is connected.
A reverse current prevention diode 14 is incorporated as shown in FIG. 6 to prevent the destruction of D8. If at least one such reverse current prevention diode 14 is provided for one vehicle lamp, For this reason, it is not usually incorporated into the circuit of the module type LED 4, but is separately connected after assembling the vehicle lamp. However, retrofitting the reverse current prevention diode 14 for each lamp increases the number of work steps, which is a significant factor in cost increase.

Accordingly, the present invention has been made in view of the above-mentioned conventional problems, and has as its object to eliminate the necessity of retrofitting a diode for preventing reverse current, and to improve the assembling workability. It is an object of the present invention to provide a vehicular lamp.

[0008]

The present invention achieves the above object by providing a plurality of LEDs connected in series for each column .
And the LEDs in each row are connected in parallel to the power supply.
With multiple module type LEDs
Power supply with mechanical connection of module type LED
Connected in parallel to the plurality of modules
Die for preventing reverse current on the positive side of the power supply of the type LED
Aether is directly connected.

[0009]

In the present invention, a plurality of module types L
Module type LE that is directly connected to power supply in ED
Since D uses a diode for preventing reverse current flow, a diode connection step after assembling the lamp is omitted. Reverse current prevention
The diode prevents the LED from being destroyed by preventing current from flowing when the lamp is connected to the power supply in a positive or negative direction.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 is an external perspective view of a module type LED showing one embodiment of a vehicular lamp according to the present invention, FIG.
3 is an enlarged sectional view of a main part of the lamp, and FIG. 3 is an electric circuit diagram of the lamp. In the drawings, the same components as those in FIGS. 4 to 6 are denoted by the same reference numerals, and description thereof will be omitted. In these figures, the present embodiment is a module type LED 4
As a conventional type of module type LED 4 B without a reverse current preventing diode, manufactured two types of module types LED 4 A with the reverse current preventing diode 14, provided with a reverse current preventing diode during assembly of the lamp a plurality of free module type LED 4 B (1 single depending lamp size) were prepared, reverse current preventing diode 1
4 Prepare one module type LED 4 A having a
These are electrically and mechanically connected by a lead wire 20. In this case, reverse current prevention diode
The module type LED 4A provided with the LED 14 is shown in FIG.
To the positive side of the power supply via the light emitting diode 14
Connected directly.

In each of the module type LEDs 4A and 4B, a total of nine LEDs 8 are arranged in three rows both vertically and horizontally. These LEDs 8 are connected in series via a current control resistor 13 for each row, and the LE 8 of each row is connected.
D8 is connected in parallel to the power supply. The LED 8 and the reverse current preventing diode 14 are connected in series to a power supply. Therefore, even if the lamp is unexpectedly connected to the power source in the positive or negative direction, no current flows due to the reverse current preventing diode 14,
Module type LED4A, module type LED
The 4B LED 8 is not destroyed.

The current control resistor 13 generally has a lead wire and is inserted into a lead wire hole of a board and soldered by a so-called lead-through type resistor or conductive pattern via a solder paste. Although a surface-mount type chip resistor to be mounted is used, in the present embodiment, a thin-film printed resistor is used, and as shown in FIG. An example in which printing is performed over the conductive patterns 7, 7 is shown. Various materials are known as the material of the thin-film printed resistor 13, but in this embodiment, the thin-film printed resistor 13 is formed using an epoxy-based thick-film resistor material. The film thickness is about 30 μm, and the thermal expansion coefficient is close to that of the transparent resin 11 because it is epoxy-based.

In forming such a thin-film printed resistor 20, after the conductive pattern 7 is formed by printing, an epoxy-based thick-film resistor material is applied between the defined conductive patterns in each column by a screen printing method or the like. Next, the resistance material is baked at a predetermined temperature to be baked on the insulating substrate 6, and then the resistance value is checked and trimmed by a laser or the like so as to obtain a predetermined value.

The insulating substrate 6 has a portion on which the LED 8 is mounted as an LED mounting portion, and thinner lead wire connecting portions 21 are integrally provided on both sides of the LED mounting portion. On the surface of the portion 21, a land portion 22 of the conductive pattern 7 and a lead wire insertion hole 23 through which the lead wire 20 is inserted are formed. The lead wire 20 is inserted into the lead wire insertion hole 23, and is soldered and connected to the land 22 by a dip soldering method, a reflow soldering method, or the like. When the lead wire connecting portion 21 is formed one step lower than the LED mounting surface, light emitted from the LED 8 hits the lead wire 13 and is reflected, and there is no fear that the reflected light and the direct light from the LED 8 interfere with each other. Good light distribution characteristics can be obtained as a lamp. The other configuration is the same as the conventional structure.

[0015] Thus in the vehicle lamp having such a structure, mode <br/> module type LED4A reverse current preventing diode having a reverse current prevention diode 14 1
Since two types of module type LEDs 4B having no LED 4 are manufactured, and these are electrically and mechanically connected to assemble the lamp, the connection step of the reverse current prevention diode 14 which was conventionally required is unnecessary. Accordingly, the assembling process of the lamp can be simplified. Further, the thin film printed resistor 13 as the current controlling resistor is extremely thin as compared with the conventional lead-through type resistor and chip resistor, so that the module type LED 4 and the lamp itself can be thinned. Further, since it is thin, even if it is provided on the insulating substrate 6, there is no adverse effect on the light distribution characteristics of the lamp. Further, the thin film printed resistor 13 itself is thin and small, and has a coefficient of thermal expansion close to that of the transparent resin 11 and does not require soldering. Therefore, the thin film printed resistor 13 is resistant to thermal stress and bending, and cracks or peels off. Less is. In addition, if it is thin, air bubbles are less likely to adhere to the thin film printing resistor 13 when molded with the transparent resin 11, and deterioration due to air bubbles can be prevented. Furthermore, since the lead wire connecting portion 21 is formed lower than the LED mounting portion, there is little possibility that the lead wire 20 blocks light emitted from the LED 8, and a good lighting effect can be obtained.

[0016]

As described above, according to the vehicle lamp of the present invention, a plurality of LEs connected in series for each row are provided.
D, and the LEDs in each row are connected in parallel to the power supply.
A plurality of module-type LEDs
While connecting these module type LEDs mechanically
Connected in parallel to the power supply,
For preventing reverse current on the positive side of the power supply of the LED
Since the diodes are directly connected, there is no need to connect a diode for preventing reverse current after assembling the lamp , so that the lamp assembling process can be simplified. As a result, the manufacturing cost of the lamp can be reduced, and the lamp can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a module type LED showing one embodiment of a vehicular lamp according to the present invention.

FIG. 2 is an enlarged sectional view of a main part of the lamp.

FIG. 3 is an electric circuit diagram of the lamp.

FIG. 4 is a partially broken front view showing a conventional example of a vehicular lamp.

FIG. 5 is an enlarged sectional view taken along line VV of FIG.

FIG. 6 is an electric circuit diagram of the lamp.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lamp body 2 Front lens 3 Light room 4 Module type LED 6 Insulating substrate 7 Conductive pattern 8 LED 10 Bonding wire 11 Transparent resin 12 Convex lens part 13 Current control resistance 14 Reverse current prevention diode

 ──────────────────────────────────────────────────続 き Continued on the front page (56) References JP-A-62-285303 (JP, A) JP-A-3-120879 (JP, A) JP-A-5-45812 (JP, U) JP-A-5-28512 25604 (JP, U) JP 459010 (JP, U) JP 323612 (JP, Y2)

Claims (1)

(57) [Scope of request for utility model registration] 1. A plurality of LEs connected in series for each column
D , and the LEDs in each row are connected in parallel to the power supply.
A plurality of module-type LEDs
While connecting these module type LEDs mechanically
Connected in parallel to the power supply,
For preventing reverse current on the positive side of the power supply of the LED
A vehicular lamp to which a diode is directly connected .