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:
Jul. 06, 1993
Filed:
Nov. 04, 1991
Gerald Dufrenne, LaVerne, CA (US);
Unitek Equipment Inc., Monrovia, CA (US);
Abstract
The motorized weld head employs a control system which allows user control of critical welding parameters such as speed, force, position, and duration. The control system includes a position servo loop attached to a motor-driven output shaft on which a welding electrode is mounted via a spring. During a weld cycle, the control system moves the welding electrode toward a workpiece at a rapid user-defined rate. Just prior to when the electrode contacts the workpiece, the speed of the electrode is reduced to prevent damage to the parts. When contact is made, a pressure transducer measures the force exerted by the electrode on the workpiece. A comparator continuously monitors the force measured by the transducer and changes state when the measured force equals a user-defined optimum welding force. A signal is then passed to the servo loop commanding it to hold the position of the electrode effectively maintaining the applied force on the workpiece. When mechanical vibrations diminish, a user-defined weld current is enabled to the electrode. After the weld current is fired, the constant force is maintained until the weld cools. Finally, the welding electrode is automatically raised by the control system, releasing all pressure on the workpiece.