The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 18, 2006
Filed:
Jun. 25, 2001
Wade Lee, Danville, CA (US);
Wade Lee, Danville, CA (US);
EML Technologies LLC, Danville, CA (US);
Abstract
An enhanced built-in visual warning mechanism to caution a user when the surfaces of a worklight are hot. A worklight is shown that has a housing that includes an interior portion for holding a light source such as one or more quartz halogen bulbs. The light source operates at a temperature sufficient to raise at least portions of the exterior surfaces of the housing to a temperature that is hot to human touch during normal operation of the worklight. A thermochromic substance is disposed in thermal communication with at least a portion of one of the exterior housing surfaces in a readily visible position. The thermochromic substance is formulated to undergo a conspicuous color change, in the normal operation of the worklight, in response to heat from the external surface where it is located. The dynamic color change provides a timely visible indication to the user that the exterior surface is presently hot to the touch. In some embodiments a thermal moderator is introduced between the hot worklight surface and the thermochromic substance to moderate the heat level applied to the thermochromic substance.