IP Library › Granted Patent US 4,791,960
Granted Patent Utility
US 4,791,960 · App. 07/076,501

Semi-pilot operated four-way valve

Inventor: John E. Ellison
Patented Case View Patent ↗
Granted: Dec 20, 1988 Filed: Jul 22, 1987
Inventor
John E. Ellison
Assignee (at issue)
Parker-Hannifin Corporation

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Quick Facts
Patent No.
US 4,791,960
App. No.
07/076,501
Filed
1987-07-22
Granted
1988-12-20
Kind
A