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:
Apr. 27, 1982
Filed:
Nov. 06, 1979
Jean L Dauvergne, Fosses, FR;
Societe Anonyme Francaise du Ferodo, Paris, FR;
Abstract
The invention relates to a master cylinder for an automobile braking circuit which is suitable for dual-circuit or single-circuit application. The master cylinder has at least one chamber connected to the braking circuit, the pressure in the chamber being controlled by depression of a master piston by a brake pedal. An auxiliary hydraulic circuit is connected to the master cylinder and this circuit has a source of pressure and a jack, a piston of which co-operates with the master piston to cause depression thereof; a distributor is provided suitable for feeding the jack with auxiliary hydraulic pressure from the source, the distributor having a slide valve which is subjected to two opposing forces, one of which is developed by the auxiliary hydraulic pressure and the other of which is developed by the action of the pedal via means for transmitting this force between the pedal and the slide valve, with the intervention of elastic means for simulating the pedal movement, and manual backup means acting on the master piston, from the pedal, in the event of failure of the auxiliary circuit. A movable member in the master cylinder which is controlled by the auxiliary hydraulic pressure at the same time as the slide valve of the said distributor, is associated with the elastic means for simulating the pedal movement, so as to put these means out of action in response to a failure of the auxiliary hydraulic pressure. According to the invention, the manual back-up means, the movable member, and the slide valve of the distributor act respectively along three separate and parallel axes.