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. 21, 2003
Filed:
Feb. 26, 2002
Applicant:
Inventors:
Stephen J. Schoonmaker, Chambersburg, PA (US);
Jeffrey L. Addleman, Chambersburg, PA (US);
Assignee:
Grove U.S. LLC, Shady Grove, PA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F15B 1/520 ;
U.S. Cl.
CPC ...
F15B 1/520 ;
Abstract
A method and apparatus for operating a load lifting device to move a load and hold the load steady is disclosed. In the conventional arts, a lifted or lowered suspended load had a tendency to move from its desired position, as hydraulic fluid in the lifting system cooled, e.g. a stick slip condition. The present invention monitors a fluid pressure in the lifting system and compensates the fluid pressure to accommodate any pressure drop due to fluid cooling. Thereby, the load can be effectively held steady at a desired position, and the stick slip condition can be avoided.