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:
Oct. 11, 1983
Filed:
Apr. 24, 1981
Daniel P Dodson, Florence, SC (US);
George C Ludwig, Marion, SC (US);
AVM Corporation, Jamestown, NY (US);
Abstract
A pneumatic, piston/cylinder counterbalance in which the counterbalance force is obtained by differential pressure across the piston and in which the force changes due to temperature are compensated by use of a variable volume cylinder having one or more auxiliary chambers separated by walls, each including a temperature responsive bi-metal disc valve normally acting as a check valve permitting flow into the auxiliary chambers but preventing flow out of the chambers except when the temperature drops to a predetermined value. In the multiple auxiliary chamber embodiment, flow into and out from each chamber is controlled by an associated bi-metal disc valve responsive to successively lower temperatures to enable a more linear stabilization of force output regardless of temperature.