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:
Jul. 03, 1979
Filed:
May. 08, 1978
Wayne A Peterson, Washington, IL (US);
Caterpillar Tractor Co., Peoria, IL (US);
Abstract
A hydraulic brake system with pilot actuation for the braking of a vehicle is disclosed. The brake system includes a service brake valve, a park brake valve and a retard brake valve. The hydraulic brake system further includes an additional brake valve including two separate spools slidably disposed within a valve body, each being responsive to pilot pressure from the above-disclosed valves. The first of the spools in the additional brake valve communicates pilot pressure from a fluid pressure source to the rear brakes of the vehicle and from the rear brakes to a fluid pressure reservoir or sump. The second spool communicates fluid from the fluid pressure source to the front brakes and from the front brakes to the fluid pressure reservoir. The first spool of the additional brake valve is also independently responsive to pilot pressure from at least one of the above disclosed valves which responsiveness allows for a variance in braking force between the front and rear brakes.