Light assembly incorporating reflective features

• US 8,197,110 B2
• Filed: 03/01/2007
• Issued: 06/12/2012
• Est. Priority Date: 10/10/2003
• Status: Active Grant

• Current Assignee: Federal Signal Corporation
• Original Assignee: Federal Signal Corporation
• Inventors: Czajkowski, Bob
• Primary Examiner(s): HAN, JASON
• Application Number:
  US11/712,769
• Publication Number:
  US 20070153530A1
• Time in Patent Office: 1,930 Days
• Field of Search: 362240-241, 362/247, 362296-298, 362301-302, 362/341, 362/346, 362516-518, 362/249.02, 362/311.07, 362/545, 362/800
• US Class Current: 362/518
• CPC Class Codes: F21S 4/20 with light sources held by or within elongate supports
• CPC Class Codes: F21S 41/00 Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps reversing lights F21S43/00
• CPC Class Codes: F21S 43/14 Light emitting diodes [LED]
• CPC Class Codes: F21S 43/15 Strips of light sources
• CPC Class Codes: F21S 43/30 characterised by reflectors
• CPC Class Codes: F21S 45/48 with means for conducting heat from the inside to the outside of the lighting devices, e.g. with fins on the outer surface of the lighting device
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21V 7/005 with an elongated shape to cooperate with linear light sources
• CPC Class Codes: F21V 7/04 Optical design
• CPC Class Codes: F21V 7/06 with parabolic curvature
• CPC Class Codes: F21V 7/09 with a combination of different curvatures
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

A light assembly is disclosed which can include one or more light emitting diodes and a reflector. The reflector includes a reflective surface and is positioned to reflect at least a portion of the light emitted by the light emitting diode. The reflector further includes a pair of flanking planar reflective surfaces. The flanking planar reflective surfaces can be positioned at a distance one half the predetermined distance between two light emitting diodes, and can simulate an extended length of the reflector.

Claims

1. A light assembly comprising:

an array of light emitting diodes for a warning light generating a beam pattern having a center axis, wherein the light emitting diodes are arranged along a line, and wherein adjacent light emitting diodes are each regularly spaced at a first distance relative to one another along the line;

a plurality of contiguous reflective regions with each region having optical properties distinct from optical properties of adjacent regions, where the plurality of contiguous reflective regions form a composite reflective surface having a generally parabolic cross-sectional shape, the composite reflective surface positioned to reflect at least a portion of the light emitted by each of the light emitting diodes from each of the reflective regions such that a center axis of the reflected light reflects in a direction generally perpendicular to the center axis of each of the light emitting diodes;

one of the plurality of contiguous reflective regions including a plurality of parabolic regions configured to direct a portion of the reflected light emitted from the array of light emitting diodes to the center axis, with one of the parabolic regions corresponding to each of the light emitting diodes, and further comprising a second region bordering each of the parabolic regions configured to direct light up and down; and

a pair of flanking reflective surfaces positioned on opposed ends of the array of light emitting diodes, each of the flanking reflective surfaces being flat, the flanking reflective surfaces each including a leading edge positioned adjacent to an outermost point of the contiguous reflective regions, and a trailing edge following the contiguous reflective regions to the leading edge, and the line along which the array of light emitting diodes is arranged intersects and is normal to each of the flanking reflective surfaces, wherein each of the flanking reflecting surfaces is positioned at a second distance, the second distance being one half the first distance between adjacent light emitting diodes so that the flanking reflective surfaces simulate an extended length of the reflector.

2. The light assembly of claim 1, wherein the reflective surface includes a curved section.

3. The light assembly of claim 1, wherein the reflective surface further includes a reflective region configured to direct light at various angles extending outward from the reflector.

4. The light assembly of claim 1, wherein the reflective surface further includes a reflective region configured to direct light five degrees up and down.

5. The light assembly of claim 1, further comprising a power supply operably arranged with the array of light emitting diodes such that the array is selectively operable to emit light.

6. The light assembly of claim 1, further comprising a heat sink operably arranged with the array of light emitting diodes.

7. A light assembly for directing light comprising:

light emitting diodes (LEDs) for a warning light extending along a line, each having an optical output axis;

a reflector comprising a composite of parabolic curve sections, each having a principal axis that is substantially perpendicular to the optical output axis of each of the one or more LEDs so as to redirect light from each of the LEDs along a direction substantially in common with a common direction of the principal axes; and

one of the parabolic curve sections including a plurality of parabolic regions configured to direct a portion of the reflected light emitted from each of the LEDs to the optical output axis, with one of the parabolic regions corresponding to each of the LEDs, and further comprising a second region bordering each of the parabolic regions configured to direct light up and down;

a pair of flanking reflective surfaces cooperating with the composite of parabolic curve sections to provide a substantially unidirectional spatial pattern of light emanating from the one or more LEDs, the flanking reflective surfaces being perpendicular to the reflective surface and parallel to one or more planes including both an output optical axis of a light emitting diode from the one or more LEDs and a center axis of light reflected by the reflector originating from the light emitting diode, and the line along which the LEDs extends is normal to the flanking reflective surfaces.

8. The light assembly of claim 7, wherein the pair of flanking reflective surfaces is each planar.

9. The light assembly of claim 7, wherein the pair of flanking reflective surfaces is each substantially parabolic.

10. The light assembly of claim 7, wherein the pair of flanking reflective surfaces is positioned on opposed ends of the one or more light emitting diodes at a distance one half a predetermined distance between two LEDs.