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. 05, 1998
Filed:
Jul. 31, 1996
Kyoji Moro, Chiba-ken, JP;
Hiroshi Shimada, Chiba-ken, JP;
Miyachi Technos Corporation, Chiba-ken, JP;
Abstract
An inverter resistance welding control or power supply apparatus includes a clock generator which generates a clock signal defining a switching cycle of an inverter in a resistance welding machine, a device for preselecting a predetermined reference value corresponding to a desired current peak, a current sensor for detecting primary or secondary current of the welding machine, and an inverter control for controlling the inverter on a switching cycle-by-cycle basis. Specifically, the apparatus turns on the inverter in response to a leading edge of the clock signal, and turns the inverter off either when the current detected signal has reached the reference value or when the clock signal has reached a trailing edge. The control apparatus further includes a magnitude evaluator for measuring a magnitude of the current from the detected signal, which magnitude is expressed in root mean square, arithmetic mean or averaged peak value. The control apparatus further includes a reporter monitor which reports, based on the measured results of the current, information useful to determine normal or defective operation. There may further be provided a lack-of-secondary current detector for operatively and reliably detecting a lack of secondary current by monitoring the primary current.