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. 07, 2006
Filed:
Jun. 25, 2004
Tatsuya Mukai, Tsu, JP;
Nobuhiro Kitamura, Katano, JP;
Yukihiro Murata, Hirakata, JP;
Kenji Okada, Nishinomiya, JP;
Tatsuya Mukai, Tsu, JP;
Nobuhiro Kitamura, Katano, JP;
Yukihiro Murata, Hirakata, JP;
Kenji Okada, Nishinomiya, JP;
Matsushita Electric Works, Ltd., Osaka, JP;
Abstract
In a phase controller used in a light control of an incandescent lamp, noise reduction, prevention of elements from damage due to short circuit current, downsizing and lower cost are purposed. A CPU circuit of a control circuit sets a gradual increase term during which a load voltage applied to the incandescent lamp is gradually increased by driving a self-quenching type switching device such as an IGBT. After passing the gradual increase term, a main switching device such as a TRIAC is turned on. The phase controller further comprises a current sensor such as a shunt resistor for sensing a value of the load current flowing through the self-quenching type switching device, according to need. The CPU circuit compares the sensed value of the load current with at least one reference value, and selects driving manner of the main switching device and the self-quenching type switching device corresponding to the result of comparison.