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. 09, 1995
Filed:
Dec. 29, 1993
Glenn A Geithman, Renton, WA (US);
Duncan P MacKinnon, Woodinville, WA (US);
Gary D Benham, Snohomish, WA (US);
Babak Sayyadi, Bothell, WA (US);
Robert T Yankis, Redmond, WA (US);
The Boeing Company, Seattle, WA (US);
Abstract
A fiber optic cable extends into the housing of an induction heater and has a sensing end positioned to confront a part being heated. Infrared radiation from the part is transmitted by the cable to a transducer. The transducer converts the infrared energy into an electrical signal that is used by a control circuit to control the heating operation. The control circuit has an internal electronic timer that is used in normal operation and to detect certain failure conditions. In normal operation, electromagnetic pulses are provided to the heater at a predetermined power level until the part reaches a predetermined temperature. Then the control circuit adjusts the power level to hold the part at the temperature for a brief holding period. The timer is used by the control circuit to detect failure to reach a desired temperature after a maximum delay and to detect dropping of the temperature below a minimum level during the holding period. The control circuit also detects overheating of the workpiece. The control circuit adjusts and terminates the power level through a silicon controlled rectifier which receives a pulse train from the control circuit.