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. 28, 1978
Filed:
Jan. 27, 1977
Edwin D Ditto, Bloomfield Hills, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A compression molding operation is controlled by applying a press force to a mold having a cavity charged with molding compound. The separation of the mold halves is measured at each corner thereof by linear variable differential transformers. Hydraulic cylinders operating on the press ram generally in the area of each corner of the molds are individually controlled to locally vary the press force on the molds to maintain mold parallelism as determined by the LVDT's to control the velocity of press closing also as measured by the LVDT's according to a preprogrammed velocity profile, and further to control the amount of press force applied to the molds according to a preprogrammed value during curing of the molding compound.