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:
Jan. 24, 1989
Filed:
Jan. 19, 1988
Applicant:
Inventors:
Kenneth D Kramer, Waterloo, IA (US);
Gregory E Sparks, Waterloo, IA (US);
Assignee:
Deere & Company, Moline, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16K / ;
U.S. Cl.
CPC ...
251 3004 ; 251 38 ; 251 50 ; 251 36 ;
Abstract
A pilot operated control valve includes a spool type pilot valve member which is coupled to the main valve member by a pair of springs so that both pilot pressure forces and spring forces act on the main valve member. The main valve member and the housing in which it moves enclose a damping chamber. A damping orifice extends through the main valve member and connects the damping chamber with a pilot pressure chamber to reduce vibration of the main valve member.