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:
Sep. 21, 1976
Filed:
Sep. 13, 1972
Mark J Fogelberg, Elk Grove Village, IL (US);
Frank E Hill, Warren, MI (US);
Borg-Warner Corporation, Chicago, IL (US);
Abstract
A variable ratio master cylinder designed to operate, in one phase, to take up slack in a braking system by displacing a relatively large volume of fluid at a low pressure with minimum pedal travel and then gradually shift to another phase in which a smaller volume of fluid is displaced at a higher pressure with increased pedal travel to apply the brakes. The master cylinder includes a differential area metering valve which begins to open at a predetermined pressure in the pressure chamber and remains open above a predetermined second pressure and sealing means cooperative with at least one piston to seal off communication between the pressure chamber and the rear of the piston during the pressure stroke of the piston but to allow communication between said chambers on the return stroke of the piston for rapid return to the released state.