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:
Mar. 28, 1978
Filed:
Mar. 22, 1977
Applicant:
Inventor:
Allyn J Hein, Camdenton, MO (US);
Assignee:
Caterpillar Tractor Co., Peoria, IL (US);
Primary Examiner:
Int. Cl.
CPC ...
F04B / ;
U.S. Cl.
CPC ...
137118 ; 60449 ; 417216 ;
Abstract
A combined summing and underspeed valve including a valve body having a bore, a spool within the bore, an outlet from the bore in the body intermediate the ends of the bore, a pair of spaced inlets in the bore for receiving fluid under pressure to apply force to opposite ends of the spool, at least two additional inlets in the body for receiving fluid under pressure to apply force to one of the ends of the spool, and pistons for isolating fluid from the inlet of the pair applying force to the spool one end from fluid from the additional inlets while applying force to the spool.