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:
May. 27, 1997
Filed:
May. 01, 1995
David W Knoble, Tupelo, MS (US);
Khosrow Jamasbi, Belden, MS (US);
James V Olson, Indianapolis, IN (US);
Thomas Lighting, Tupelo, MS (US);
Abstract
A control relay circuit and method for controlling a relay having a coil, for use, in particular, in operation of a light fixture circuit having an HID lamp. The relay control circuit has an input for receiving a control voltage signal and a voltage storage element connected across the input. The voltage storage element develops a voltage level as a function of time in response to the control voltage signal. A thyristor circuit, a switching element and the coil of the relay form a series circuit that is connected in parallel to voltage storage element A switch controller is connected in parallel to the voltage storage element and is also connected to the switching element. In response to the control voltage being received at said input, the switch controller activates the switching element to a conductive state at a first voltage level across the voltage storage element and the thyristor changes from a non-conductive state to a conductive state at a second voltage level across the voltage storage element, the first voltage level being less than the second voltage level. In response to the control voltage being removed from the input, the switch controller activates the switching element to a non-conductive state at a third voltage level across the voltage storage element thereby changing the thyristor from the conductive state to the non-conductive state thereof, the third voltage level being less than the second voltage level. The relay is energized at the second voltage level and is deenergized at the third voltage level.