The price continues to drop 2000 yen LED bulbs listed
LED bulbs of around 2,000 yen or even cheaper have appeared.
By installing a plurality of small LEDs to improve heat dissipation, a low-cost resin substrate can be used.
A low-cost construction that takes into account ease of assembly.
In June 2009, Sharp introduced LED bulbs with a price of around 4,000 yen. Companies are scrambling to follow suit and push for lower prices. Then, in December 2009, just after half a year or so, LED bulbs with a price of only about 2,000 yen began to be listed.
One of them is the "Luminous" series (hereinafter referred to as Luminous bulb) jointly developed by Doion Electric (headquarters: Echizen City, Fukui Prefecture) and Doshisha, which was launched on December 14, 2009 (Fig. 1(a) ). The power consumption is 6.6W, the total luminous flux is 420lm (white), and the equivalent of 60W incandescent lamp is priced at 2,480 yen (including tax); the power consumption is 4.7W, and the total luminous flux is 310lm (white). The product equivalent to a 40W incandescent lamp is priced at JPY 1980 (tax included). In addition, on December 22, the Otsuka Chamber of Commerce listed the LED bulb "Lumidas-CL" series developed by FAWOOTechnology in Korea at a price of 2,380 yen (including tax) (Fig. 1(b)). The series includes products that consume 5W and a total luminous flux of 292lm (white) instead of 20-30W incandescent lamps.
Among the "Luminous bulbs" jointly developed by Hollywang Motor and Doshisha, the price of a 40W incandescent lamp is 1,980 yen, which is a significant price reduction (a). The LED bulb "Lumidas-CL" produced by FAWOOTechnology of Korea, which is listed on the Otsuka Chamber of Commerce, features a slim shape that dissipates heat from the inside of the air vent that penetrates the central portion of the heat sink (b).
Equipped with dozens of LED packages
The key to achieving low prices for Luminous bulbs, which is "Devosha Lifestyle Business Unit, Director of Lifestyles and Commodities, Director of Downhole Masters" is that the bulbs are equipped with many small LED packages (Figure 2). The equivalent of a 60W incandescent lamp is equipped with 40 LED packages, and the equivalent of a 40W incandescent lamp is equipped with 34 LED packages.
In the past, many manufacturers used LED packages with an input power of 1W in LED bulbs. Luminous bulbs are equipped with a hundred and dozens of mW LED packages. Although the number of packages that need to be installed has increased, "the total cost of LED packaging has been reduced" (Doshisha). However, to install a large number of LED packages, it is difficult to reduce the area of a€?a€?the mounting substrate. In order to make LED bulbs suitable for existing lighting fixtures, many manufacturers have controlled the diameter of LED bulbs to be less than 60mm as incandescent lamps, but Luminous bulbs have increased by 4mm to 64mm.
40 small LED packages were installed in products equivalent to 60W incandescent lamps. The heat of the mounting base plate can be transferred to the heat sink via the metal plate.
The use of a small LED package also contributes to improved heat dissipation. Since the small heat source is dispersed on the LED substrate, there is no place where the temperature rises, and the temperature of the substrate is easily made uniform.
The Luminous bulb's LED mounting base plate uses a metal base plate in a product equivalent to a 60W incandescent lamp, while a resin base plate is used instead of a metal base plate in a product equivalent to a 40W incandescent lamp. "Although the thermal conductivity is excellent, it is not necessary to use a more expensive metal substrate (Doshisha) in products with less LED package and lower heat generation." The equivalent of a 40W incandescent lamp makes a huge contribution to the price of less than 2,000 yen.
Ring configuration LED
Lumidas-CL also uses a number of methods with small LED packages, just like Luminous bulbs. The number of equipment is 20. In addition, a low-cost structure that allows for easy assembly is used. For example, in the assembly of the resin case, a snap-on (SnapFit) is used, and the connection of the LED mounting board, the power supply circuit board, and the base is welded. Methods. In addition, it has obtained the Korean LED lighting safety standard certification.
A hollow shape in which the tip is tapered is used, and a three-layer structure in which a lens, a mirror, and a heat sink are respectively formed from the outside. The LED package is mounted on a toroidal backplane and then mounted on the root of the heat sink.
The appearance is a unique slender shape, which at first glance looks like there is no heat sink, but in fact the heat sink is embedded in the central part of the bulb (Figure 3). A three-layer structure of a lens, a mirror, and a heat sink from the outside is used, and an annular LED mounting substrate is attached to the root of the heat sink (near the lamp socket).
The surface of the lens has small holes, and air can enter and exit between the through hole in the central portion of the heat sink and the outside. In other words, Lumidas-CL uses a structure that dissipates heat from the inside of the through hole of the heat sink. Further, in order to facilitate air circulation, a slit is provided in the bottom plate of the power supply circuit disposed under the heat sink, and a slit is provided in the resin case under the bulb. In this way, the air can flow up and down inside the bulb.