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:
Feb. 08, 2005
Filed:
Jul. 01, 2002
Henry Frazier Pruett, Sandy, OR (US);
Gerald E. Duffy, Portland, OR (US);
Henry Frazier Pruett, Sandy, OR (US);
Gerald E. Duffy, Portland, OR (US);
InFocus Corporation, Wilsonville, OR (US);
Abstract
A safety interlock apparatus for an electrical device includes a DC power supply, a ballast power supply including a ballast control circuit that controls a ballast power circuit, and a lamp. A relatively low voltage electrical connection is present between the DC power supply and the ballast control circuit. A relatively high voltage electrical connection is present between the lamp and the ballast power circuit. A safety interlock switch is positioned on the relatively low voltage electrical connection, the switch having a closed state wherein the relatively low voltage is supplied to the ballast control circuit and an open disconnected state wherein the relatively low voltage electrical connection is disconnected. A panel is fixable to the electrical device frame, and is selectively movable to expose the lamp for removal. The panel has a switch actuator positioned thereon operable to actuate the interlock switch to the open disconnected state when the panel is removed from the device, thereby disconnecting power to the ballast control circuit, which in turn immediately disables the ballast power circuit, rendering the lamp safe for removal.