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. 28, 1980
Filed:
Mar. 05, 1979
Francis E Schlueter, Des Moines, IA (US);
Russell D Copley, Ankeny, IA (US);
Leon F Sanderson, Des Moines, IA (US);
Deere & Company, Moline, IL (US);
Abstract
An agricultural harvesting machine having a plurality of independently supported row crop harvesting units is provided with a hydraulically operated vertical positioning mechanism for adjusting the height of the units in accordance with ground surface variations. Each unit is provided with a ground-engaging feeler mechanically coupled to a control valve which adjustably varies the hydraulic fluid flow to a single acting unit lift cylinder. The cylinder includes fluid bypass capabilities to permit continued hydraulic fluid flow upon full extension of the cylinder piston and thereby avoid a fluid system pressure and consequent temperature increase.