Work area lighting system

• US 4,233,651 A
• Filed: 03/30/1978
• Issued: 11/11/1980
• Est. Priority Date: 03/30/1978
• Status: Expired due to Term

• Current Assignee: KCS Lighting Incorporated A Corporation of
• Original Assignee: Keene Corp. (Steel Partners Holdings LP)
• Inventors: Fabbri, William C.
• Primary Examiner(s): Jordan, Charles T.
• Assistant Examiner(s): Miles, Edward F.
• Application Number:
  US05/891,697
• Time in Patent Office: 957 Days
• Field of Search: 362/33, 362/127, 362/187, 362/222-224, 362/256, 362/260, 362/268, 362/277, 362/279, 362/281, 362/290, 362/330-331, 362/354, 362/359, 362/248, 362/280, 362/303 , 362/319, 362/351, 362/217, 362/235, 362/244, 362/246, 362/307-309, 362/311, 313/117 X, 350/278, 350/283, 351/46-47
• US Class Current: 362/33
• CPC Class Codes: F21V 14/06 by movement of refractors in vehicle head lamps F21S41/635
• CPC Class Codes: F21V 5/02 of prismatic shape F21V5/04 takes precedence
• CPC Class Codes: F21V 7/0016 on lighting devices that also provide for direct lighting, e.g. by means of independent light sources, by splitting of the light beam, by switching between both lighting modes
• CPC Class Codes: F21Y 2103/00 Elongate light sources, e.g. fluorescent tubes
• CPC Class Codes: F21Y 2113/00 Combination of light sources

Abstract

A work area lighting system is provided including a housing containing a linear light source therein and having an open bottom end. A refractor comprising a pair of refractor plate members closes the open bottom end. The refractor includes a first member having a plurality of spaced prisms extending parallel to the light source and a second member having a plurality of spaced prisms extending perpendicular to the light source. The second member underlies the first member and is approximately one-half its length. The second member is moveably mounted to the housing to enable it to slide with respect to the first member so that different portions of the first member may be covered as desired.

Claims

1. A work area lighting system for providing a combination of substantially glare-free and non-glare-free light comprising:

a housing positioned above said work area, said housing having an open bottom end;

an elongated linear light source having a longitudinal axis mounted within said housing;

a refractor comprising a pair of superimposed plate members mounted to said housing closing said open bottom end, said refractor having a first refractor plate member substantially co-extensive in length with said light source and a second refractor member shorter in length than said first member along said longitudinal axis whereby substantially all the luminous flux eminating from said light source directed toward said refractors passes through said first refractor plate member but only a portion of the luminous flux passing through said first refractor plate passes through said second refractor plate; and

means for selectively positioning said second refractor plate along the light source longitudinal axis;

said first refractor member having light incident and emergent surfaces and said light emergent surface having a plurality of spaced prisms extending parallel to the length of said linear light source; and

, said second refractor member having light incident and emergent surfaces and said light incident surface having a plurality of spaced prisms extending perpendicular to said linear light source whereby the luminous flux passing through both said refractors is substantially glare-free and the luminous flux passing through only said first refractor is non-glare-free.

2. The system in accordance with claim 1 wherein said second member underlies said first member.

3. The system in accordance with claim 1 wherein said second member is approximately one-half the length of said first member.

4. The system in accordance with claim 1 wherein said housing has an open top end opposite said open bottom end and further comprising an open louver baffle closing said open top end.

5. A system in accordance with claim 1 wherein said selectively positioning means comprises means for slidably mounting said second refractor member with respect to said first member permitting said second member to slide in a direction parallel to said first refractor member prisms.