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:
Jun. 08, 1976
Filed:
Nov. 08, 1971
Applicant:
Inventor:
Dale A Knutson, Oconomowoc, WI (US);
Assignee:
Applied Power Inc., Milwaukee, WI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F15B / ; F15B / ;
U.S. Cl.
CPC ...
91378 ; 91416 ; 9141 / ; 91431 ;
Abstract
A proportional force amplifier having a cylinder separated by a piston assembly into a pressure chamber, a control chamber and a reservoir chamber, a spool valve mounted for axial movement within a bore in said piston assembly to selectively connect the control chamber to either the pressure chamber or the reservoir chamber, the piston assembly moving in response to the change in pressure between the pressure chamber and the control chamber a distance equal to the distance of movement of the spool valve, the spool valve being connected for actuation by a resilient compensating rod and being pressure balanced.