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:
Nov. 04, 1986
Filed:
May. 20, 1985
Applicant:
Inventor:
Donaldee Brewer, Muscatine, IA (US);
Assignee:
Bandag Licensing Corporation, Muscatine, IA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G05D / ;
U.S. Cl.
CPC ...
1371163 ;
Abstract
This invention is directed to a differential control valve. The differential pressure is maintained by differing area surfaces on a piston assembly which will be balanced at a predetermined differential established at the manufacturing operation. There is a spring member operating on two valve balls which provides a delayed pressurization of the controlled chamber. The control valve has a ball valve at the exit port to control the low pressure side of the differential control valve assembly, providing a fail-safe system with no adjustments required after manufacture if there is a pressure increase downstream.