LIGHT BULB

• US 20110273072A1
• Filed: 10/15/2010
• Published: 11/10/2011
• Est. Priority Date: 05/10/2010
• Status: Active Grant

• Current Assignee: Yadent Co., Ltd.
• Original Assignee: Yadent Co., Ltd.
• Inventors: OKI, Isamu
• Granted Patent: US 8,436,517 B2
• Time in Patent Office: Days
• US Class Current: 313/46
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21V 19/0055 by screwing
• CPC Class Codes: F21V 29/15 Thermal insulation
• CPC Class Codes: F21V 29/713 in direct thermal and mechanical contact of each other to form a single system
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21V 3/00 Globes; Bowls; Cover glasses with refracting properties F21V5/00; with reflecting properties F21V7/00; characterised by cooling arrangements F21V29/506
• CPC Class Codes: F21Y 2107/40 on the sides of polyhedrons, e.g. cubes or pyramids
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A light bulb includes an enclosure, a heat-dissipating unit, and a lamp unit. The enclosure extends along an axis, and defines an inner space therein. The heat-dissipating unit includes a hollow first heat-dissipating element disposed in the inner space, a second heat-dissipating element surrounded by the first heat-dissipating element and extending along the axial direction, and an end heat-dissipating element mounted to the second heat-dissipating element at a distal end thereof. The lamp unit includes a first circuit board disposed at a periphery of the first heat-dissipating element, a second circuit board mounted on the end heat-dissipating element, and a plurality of light-emitting elements mounted on the first and second circuit boards for emitting light beams.

Claims

1. An light bulb comprising:

an enclosure extending along an axis, defining an inner space therein, and having an open end that is registered with the axis;

a heat-dissipating unit including

a hollow first heat-dissipating element that is disposed in said inner space of said enclosure,

a second heat-dissipating element that is surrounded by said first heat-dissipating element, that extends along the axial direction, and that cooperates with said first heat-dissipating element to define a heat-dissipating compartment therebetween, and

an end heat-dissipating element that is mounted to said second heat-dissipating element at a distal end thereof that is distal from said open end of said enclosure; and

a lamp unit including a first circuit board that is disposed at a periphery of said first heat-dissipating element, a second circuit board that is mounted on said end heat-dissipating element at one side opposite to said open end along the axis, and a plurality of light-emitting elements that are mounted on said first and second circuit boards for emitting light beams.

2. The light bulb as claimed in claim 1, wherein said heat-dissipating unit further includes at least one heat-dissipating connector that interconnects said first and second heat-dissipating elements.

3. The light bulb as claimed in claim 2, wherein said heat-dissipating unit further includes a fastening member that secures fixedly said end heat-dissipating element to said second heat-dissipating element.

4. The light bulb as claimed in claim 1, wherein said heat-dissipating unit further includes a fastening member that secures fixedly said end head-dissipating element to said second heat-dissipating element.

5. The light bulb as claimed in claim 1, wherein said first and second heat-dissipating elements are spaced apart from each other in a radial direction that is transverse to the axis.

6. The light bulb as claimed in claim 5, wherein said heat-dissipating unit further includes:

a first heat-insulating member having a contact segment that is coupled to a proximate end of said first heat-dissipating element corresponding to a proximate end of said second heat-dissipating element that is opposite to said distal end thereof along the axis and that is proximate to said open end of said enclosure, and a separating segment that extends from said contact segment of said first heat-insulating member in the axial direction between said first and second heat-dissipating elements;

a second heat-insulating member disposed between said end heat-dissipating element and a combination of said first and second heat-dissipating elements, said second heat-insulating member having a contact segment that is coupled to a distal end of said first heat-dissipating element corresponding to said distal end of said second heat-dissipating element, and a separating segment that extends from said contact segment of said second heat-insulating member in the axial direction between said first and second heat-dissipating elements;

a washer mounted to said proximate end of said second heat-dissipating element and said first heat-insulating member, said end heat-dissipating element and said washer being formed with a plurality of spaced apart heat-dissipating holes that are in fluid communication with said heat-dissipating compartment;

a first fastening member securing said washer to said proximate end of said second heat-dissipating element; and

a second fastening member securing said second circuit board and said end heat-dissipating element to said distal end of said second heat-dissipating element.

7. The light bulb as claimed in claim 1, wherein said heat-dissipating unit further includes a third heat-dissipating element that has an inner end connected to said first heat-dissipating element, and an outer end extending outwardly of said open end of said enclosure, thereby permitting heat conduction from said first heat-dissipating element to said third heat-dissipating element.

8. The LIGHT BULB as claimed in claim 7, further comprising a hollow contact unit that has an inner surface defining an receiving space, said outer end of said third heat-dissipating element extending into said receiving space and being in contact with said inner surface.

9. The LIGHT BULB as claimed in claim 7, wherein said first heat-dissipating element has a mounting portion adjacent to said open end of said enclosure, said third heat-dissipating element having a mounting portion that is sleeved fittingly on said mounting portion of said first heat-dissipating element.

10. The light bulb as claimed in claim 1, wherein said first heat-dissipating element is a hollow polygonal prism, said first circuit board being a flexible printed circuit board surrounding said first heat-dissipating element, said light-emitting elements of said lamp unit being light-emitting diodes.

11. The light bulb as claimed in claim 1, wherein said enclosure further has an inner peripheral surface defining said inner space, and a fluorescent coating applied on said inner peripheral surface.