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:
Jan. 13, 1987
Filed:
Sep. 28, 1982
George C Ludwig, Florence, SC (US);
AVM, Inc., Marion, SC (US);
Abstract
A pneumatic spring counterbalance extensible link including a closed end cylinder with an end connector a piston and rod assembly within the cylinder and maintained therein by the crimped over end portion of the cylinder retaining a rod bushing and rod to cylinder seal. The cylinder is pressurized prior to assembly of the complete piston and rod into the cylinder. The piston assembly includes orifice by-pass arrangements either in the piston periphery or in a piston ring, and the piston may include a fail-safe provision in the event the orifice is clogged. A crimping die assembly is used in assembling and completing final assembly of the counterbalance components while simultaneously maintaining the link in a pressurized environment, utilizing sealed arrangement between the crimping dies to maintain pressurization of the interior of the dies and the counterbalance components prior to assembly of the components. A dual force embodiment of the counterbalance unit is disclosed and utilizes a floating sealed piston below the main piston and rod assembly entrapping pre-charged gas in the space between the floating piston and the closed end of the cylinder.