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. 16, 1989
Filed:
Dec. 08, 1986
John F Farrow, Plymouth, MI (US);
Medar, Inc., Farmington Hills, MI (US);
Abstract
High frequency resistance spot welding structure and method. In one embodiment, the structure includes dual, mirror image welding transformers, each including a transformer secondary circuit, an endless transformer core, and a transformer primary winding wound around the transformer core. The transformer secondary circuits may be single member, U-shaped transformer secondaries with integral electrode portions. In another embodiment, one of the transformers is replaced by a pair of spaced apart welding electrodes which are connected by a conductor. Means are provided for supplying welding pressure to the transformers to move them with their associated welding electrodes during a weld sequence. A high frequency, electrical welding signal is applied to the transformer primary circuits which are synchronized when two transformers are used so that the welding currents passing through the transformer secondary circuits reinforce each other. The structure is small and light weight so as to be inexpensive, positioned immediately adjacent a weld, and moved quickly. The method of the invention includes providing the high frequency welding signal to the mirror image, closely spaced apart welding structures, synchronizing the high frequency welding signal to provide push/pull welding and providing forging pressure through the transformers or transformer to move them with their associated electrodes during spot welding.