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:
Aug. 01, 1989
Filed:
Oct. 28, 1988
Applicant:
Inventors:
Assignee:
O & K Orenstein & Koppel Aktiengesellschaft, Dortmund, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E02F / ; E01H / ;
U.S. Cl.
CPC ...
172795 ; 91531 ; 60494 ;
Abstract
A grader has a grader blade which can be pressed against the ground or lifted off it by means of piston-cylinder drives. To be able to vary the downard pressure of the grader blade in its float position, either the piston chamber or the piston ring chamber of each drive can be charged with a working fluid under pressure when the grader blade is in the float position, so that the corresponding drive exerts a force on the grader blade which increases or decreases the downward pressure of the grader blade on the ground. While still allowing the grader blue to follow the contour of the ground.