Lighting units

• US 5,890,794 A
• Filed: 04/03/1996
• Issued: 04/06/1999
• Est. Priority Date: 04/03/1996
• Status: Expired due to Fees

• Current Assignee: Homayoon Abtahi, Maria Fernanda Abtahi
• Original Assignee: Homayoon Abtahi, Maria Fernanda Abtahi
• Inventors: Abtahi, Homayoon, Abtahi, Maria Fernanda
• Primary Examiner(s): Sember, Thomas M.
• Application Number:
  US08/627,119
• Time in Patent Office: 1,098 Days
• Field of Search: 362/218, 362/235, 362/240, 362/244, 362/158, 362/249, 362/252, 362/184, 362/267, 362/185, 362/800, 362/101, 362/318, 362/294, 362/373
• US Class Current: 362/294
• CPC Class Codes: B60Q 7/00 Arrangement or adaptation of portable emergency signal devices on vehicles
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21S 9/03 rechargeable by exposure to light
• CPC Class Codes: F21V 23/00 Arrangement of electric circuit elements in or on lighting devices characterised by cooling arrangements F21V29/508
• CPC Class Codes: F21V 29/506 of globes, bowls or cover glasses
• CPC Class Codes: F21V 29/56 using liquid coolants F21V29/51 takes precedence
• CPC Class Codes: F21V 29/58 characterised by the coolants
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 3/049 Patterns or structured surfaces for diffusing light, e.g. frosted surfaces
• CPC Class Codes: F21V 3/0615 the material diffusing light, e.g. translucent glass
• CPC Class Codes: F21V 3/0625 the material diffusing light, e.g. translucent plastics
• CPC Class Codes: F21V 9/12 with liquid-filled chambers
• CPC Class Codes: F21W 2111/04 for waterways
• CPC Class Codes: F21W 2111/047 for light-buoys
• CPC Class Codes: F21Y 2103/10 comprising a linear array of point-like light-generating elements
• CPC Class Codes: F21Y 2107/30 on the outer surface of cylindrical surfaces, e.g. rod-shaped supports having a circular or a polygonal cross section
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H05K 1/0209 External configuration of printed circuit board adapted for heat dissipation, e.g. lay-out of conductors, coatings
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]
• CPC Class Codes: H05K 3/3447 : Lead-in-hole components H05K3/3415 takes precedence
• CPC Class Codes: Y10S 362/80 : Light emitting diode

Abstract

lighting unit includes a circuit board having a number of LED packages extending outward from a front side. The printed circuit board is covered by a transparent cover, forming an outer cavity between the cover and the printed circuit board. The printed circuit board is supported by a housing, in which a second cavity is formed. In a first embodiment, the circuit board, being flexible, is wrapped around a cylindrical housing, with LED packages being directed radially outward. In a second embodiment, the circuit board is rigid, with LED packages being aligned in a common outward direction. In either embodiment, the outer cavity may be filled with a fluid used to promote cooling the LED packages.

Claims

1. A lighting unit comprising:

a circuit board assembly having an insulating substrate with an outer side and an inner side opposite said outer side, and a plurality of conductive circuit lands extending along said inner side;

a plurality of LED packages mounted on said outer side, with leads extending through holes in said insulating substrate and individually soldered to said conductive circuit lands, wherein each LED package within said plurality thereof includes a light-emitting segment in a base portion, a light transmitting portion extending from said base portion along an optical axis of said LED package, and a lens portion at an end of said light transmitting portion to direct light from said light-emitting segment away from said LED package, and wherein each said LED package is mounted with said optical axis thereof extending outward from said outer side and perpendicular thereto;

a transparent cover extending outwardly adjacent said LED packages, wherein a first cavity between said transparent cover and said LED packages is sealed from ambient air;

a housing extending from said inner side, with said circuit board assembly being attached to said housing and supported thereby, wherein a second cavity within said housing is sealed from ambient air, wherein said housing has a generally cylindrical outer surface extending between first and second ends thereof, and a generally cylindrical inner surface, coaxial with said generally cylindrical outer surface, extending around said second cavity, wherein said insulating substrate is flexible and is curved around said generally cylindrical outer surface, with said optical axis of each said LED package extending radially outward from said outer surface; and

a plurality of circuit wires individually attached to various of said circuit lands and extending outward through a hole in said housing; and

,

a base extending outward from said first end of said housing, with said first end of said housing being attached to said base;

wherein said transparent cover has a cylindrical cover portion extending around said circuit board assembly and said plurality of LED packages from a peripheral portion of said base, and an end cover portion extending across said second end of said housing, wherein said base includes an outer threaded portion, wherein said transparent cover includes a threaded surface at a first end thereof engaging said outer threaded portion, wherein said lighting unit includes a first gasket which is compressed as said threaded surface at said first end of said transparent cover is screwed into engagement with said outer threaded portion, and wherein said end cover portion extends across a second end of said transparent cover, said second end thereof being opposite said first end thereof, as an integral portion of said transparent cover.

2. The lighting unit of claim 1:

wherein said base includes an inner threaded portion;

wherein said housing includes a threaded surface at said first end thereof engaging said inner threaded portion; and

wherein said lighting unit includes a second gasket which is compressed as said threaded surface at said first end of said housing is screwed into engagement with said inner threaded portion.

3. The lighting unit of claim 1, wherein said first cavity is filled with a transparent cooling fluid.

4. The lighting unit of claim 3, wherein said transparent cooling fluid is a transformer oil.