Apparatus for controlling the brightness of a magnetron-excited lamp
Patent 5438242 Issued on August 1, 1995. Estimated Expiration Date: 
June 24, 2013. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
June 24, 2013. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMicrowave powered lamp having a non-conductive reflector within the microwave cavity Patent #: 5334913 InventorAssigneeApplicationNo. 080839 filed on 06/24/1993US Classes:315/219, Periodic switch in the primary circuit of the supply transformer315/224, Impedance or current regulator in the supply circuit315/248, Induction-type discharge device load315/307, Automatic regulation315/308Regulator responsive to plural conditionsExaminersPrimary: Pascal, RobertAssistant: Shingleton, Michael B Attorney, Agent or FirmForeign Patent References
International ClassH05B 037/00AbstractA power supply for providing a stable operating current to a magnetron-excited lamp. The power supply includes a DC to DC inverter for driving a primary winding of a high voltage transformer. The DC to DC inverter has a circuit including two pairs of switching elements for connecting a DC voltage supply to the primary winding. During each half of the switching cycle, one of the switching elements is pulse width modulated while the other remains on for a substantially fixed period of time. During the second half of the cycle, the remaining pair operates so that one switching device is on for a pulse width modulated period of time, and the other is on a substantially constant amount of time. The on time for the pulse width modulated switching elements is defined by an input voltage setting representing a desired brightness level for the lamp, the output magnetron current, and a representative of the integral of the current flowing through the primary of the inverter transformer.Other References
Field of SearchRegulator responsive to plural conditionsInduction-type discharge device load Periodic switch in the primary circuit of the supply transformer PERIODIC SWITCH IN THE SUPPLY CIRCUIT CURRENT AND/OR VOLTAGE REGULATION Electromagnetic influenced discharge device Bridge type For inverter Bridge type | |
