1. Technical Field
The disclosure relates to LED (light emitting diode) bulbs for illumination purpose and, more particularly, relates to an improved LED bulb having a good heat dissipation.
2. Description of Related Art
An LED bulb is a type of solid-state lighting that utilizes LED as a light source for indoor or outdoor illumination. An LED is a device for transferring electricity to light by using a theory that, if a current is made to flow in a forward direction through a junction region comprising two different semiconductors, electrons and holes are coupled at the junction region to generate a light beam. The LED has an advantage that it is resistant to shock, and has an almost eternal lifetime under a specific condition; thus, the LED bulb is intended to be a cost-effective yet high quality illumination device.
An LED bulb generally requires a plurality of LEDs mostly driven at the same time, which results in a rapid rise in operating temperature of the LEDs. However, since the bulb lacks effective heat dissipation mechanisms, continuous operation of the LED bulb can cause overheat of the LED, resulting in flickering or even malfunction of the LED.
What is needed, therefore, is an improved LED bulb which can overcome the above problems.
Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring to
Referring to
The fins 113 are arranged radially relative to the body 112. A passage is defined between every two neighboring fins 113.
A plurality of through tunnels 114 are defined in the body 112. Each of the through tunnels 114 extends through the body 112 and has two openings at the top face and a bottom face of the body 112, respectively. The through tunnels 114 are arranged along a circumferential direction of the body 112 of the heat sink 11. The through tunnels 114 are located adjacent to an outer periphery of the body 112 and close to the fins 113. The openings of the through tunnels 114 which are located at the top face of the body 112 surround the depression 1120. Each of the openings of the through tunnels 114 is located corresponding to the passage between two adjacent fins 113.
The LED 12 is thermally attached on the flat face of the depression 1120 of the base 12. In the embodiment of the present disclosure, a circuit is formed on the flat face of the depression 1120 of the body 112, and the LED 12 is electrically mounted on the circuit. It is understood that the number of the LED 12 is not limited to the present embodiment, the number of the LED 12 can also be two, three, etc..
The LED bulb further comprises an envelope 15 disposed on a top of the heat sink 11 and correspondingly covering the LED 12. The envelope 15 is integrally formed of a transparent or semitransparent material such as glass, resin or plastic. The envelope 15 is fitly engaged with the depression 1120 of the heat sink 10, whereby the envelope 15 hermetically cooperates with the body 112 to enclose the LED 12 therein for increasing the sealing performance of the LED bulb. Furthermore, the envelope 15 can function to modulate the light generated by the LED 12 to have a desired pattern.
Referring to
A plurality of through tunnels 214 are defined in the base 211. Each of the through tunnels 214 extends through the base 211 and has two openings at the top face and the bottom face of the base 211, respectively. The through tunnels 214 are arranged radially relative to the depression 2110 and the tube 212. The openings of the through tunnels 214 which are located at the top face of the base 211 surround the depression 2110. The openings of the through tunnels 214 which are located at the bottom face of the base 211 surround the tube 212. Each of the openings of the through tunnels 214, which is located at the bottom face of the base 211, is located corresponding to the passage between two adjacent fins 213. The through tunnels 214 are located adjacent an outer periphery of the base 211. Each through tunnel 214 is oriented vertically.
Referring to
A plurality of through tunnels 314 are defined in the heat sink 31. Each of the through tunnels 314 extends through the heat sink 31 and has two openings at the top face and a bottom face of the heat sink 31, respectively. The through tunnels 314 are arranged radially relative to the depression 310 of the heat sink 31. The through tunnels 314 are located adjacent an outer periphery of the heat sink 31. Each through tunnel 314 is oriented inclinedly towards the connector 30 along a top-to-bottom direction of the LED bulb.
It is to be understood, however, that even though numerous characteristics and advantages of the disclosure have been set forth in the foregoing description, together with details of the structure and function of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.