Patent Application
20120020093
1. Field of the Invention
The invention relates to a lamp, and in particular to a light unit for LED lamp and method for the same.
2. Description of Prior Art
Light emitting diode (LED) has gradually replaced the traditional light bulb, due to its small size, lower power consumption and durability, and intensively used in traffic light signal, vehicle direction lights, flashlights, cell phones, lighting and large outdoor billboard.
Currently, many of the LED lamps in the lighting are in the form of LED light units, which are made of LED dies, and these light units are formed by welding LED die on fiberglass or carbon fiber circuit substrate. The LED dies, welded to the circuit substrate, have high power characteristics and inevitably become very high heating sources when they are lighted. The extremely high heating source may affect normal use and life time of the high power LED. Therefore, manufacturers provides a heat dissipation structure on the circuit board to disperse the heating source from high power LED, and thus the high power LED can work normally and has a long life time. However, this will cause that production time and the steps of manufacturing process are increasing, and the structure of light unit may become complicated.
Since the technologies of LED field have a rapid development in recent years, the fiberglass or carbon fiber circuit substrates are replaced by MN substrates in order to overcome these deficiencies. The utilization of MN substrates not only simplifies the structure, but also makes the manufacturing process easier. However, AIN substrates are expensive, and cause an increase in production costs.
Therefore, the main purpose of the present invention is to solve the above deficiencies of prior art. The present invention provides a light unit for LED lamp and method for the same, which is a simple structure, and the cost of production can be reduced.
To achieve the above purpose, the present invention provides a method for manufacturing a light unit for LED lamp comprising the steps of: providing a aluminum substrate, which is surface-treated to form a thin aluminum oxide insulating layer thereon; preparing a circuit board, which has a through hole thereon, and having two opposite first welding areas on its one surface at the edge of the through hole and plural second welding areas for transmitting positive and negative power sources, and the circuit board having a plurality of recesses at the edge to correspond to the notches; attaching the circuit board to the insulating layer by coating a gel on its another surface to expose part of the aluminum oxide insulating layer; mounting an LED die on the insulating layer; electrically connecting two bonding wires to the LED die and the first welding areas; forming a wall on the section between the first and second welding areas of the circuit board to enclose the LED die and the two bonding wires; and dispensing plastic material into the wall to form a lens.
To achieve the above purpose, the present invention provides a structure of light unit for LED lamp, including an aluminum substrate having a thin aluminum oxide insulating layer thereon, and a plurality of notches at the edge; a circuit board provided on the insulating layer and including a through hole to expose part of the insulating layer, and having two opposite first welding areas at the edge of the through hole and plural second welding areas for transmitting positive and negative power sources, and the circuit board having a plurality of recesses at the edge to correspond to the notches; an LED die mounted to the exposed part of the insulating layer, two bonding wires electrically connecting the LED die and the two first welding areas; a wall formed on the section between the first and second welding areas of the circuit board to enclose the LED die and the bonding wires; and a lens formed inside the wall to enclose the LED die and the bonding wires.
a and 2c to 2g show schematically drawn step sequential cross section structures obtained in a process according to a preferred embodiment of the present invention.
b shows an exploded view of
A preferred embodiment of the present invention will be described with reference to the drawings.
Please refer to
In step 102 of forming an insulating layer 2, as shown in
In step 104 of attaching an circuit board 3 to the insulating layer 2, shown as
In step 106 of mounting an LED die 4 on the insulating layer 2, shown as
In step 108 of electrically connecting, as shown in
In step 110 of forming a wall, as shown in
In step 112 of dispensing a plastic material, as shown in
In step 114 of connecting power source wires, as shown in
Please refer to
When power is input to the first welding areas 32, 32′ through second welding areas 33, 33′ from two positive and negative power source wires 8, the LED die 4 is lighted. The ray produced by the LED die 4 is transmitted to outside through the lens 7, and the heating source produced by the LED die 4 is conducted to the aluminum substrate 1 through the insulating layer 2. Accordingly, the heat dissipation is proceeding by the aluminum substrate 1.
The aluminum substrate 1 has the same performance to an expensive MN substrate in the test of heat conductivity of 150 W/mk, since an aluminum oxide insulating layer 2 is formed on the aluminum substrate 1. Therefore, the manufacturing cost can be reduced.
Please refer to
While the present invention has been described with reference to a preferred embodiment thereof, it shall not be considered as the scope of invention limited thereby. All changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
