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:
Aug. 10, 1993
Filed:
Mar. 30, 1992
Jean-Pierre Gautier, Aulnay-sous-Bois, FR;
Ulysse Verbo, Aulnay-sous-Bois, FR;
Bendix Europe Services Techniques, Drancy, FR;
Abstract
The invention relates to a pneumatic brake booster comprising a casing (10), within which is located a piston (22, 14, 102) formed from a rear tubular part (22) supporting a skirt (14) and, by way of an unrolling diaphragm (12), defining a front chamber (16) connected permanently to a vacuum source and a rear chamber (18) connected selectively to the front chamber (16) or to the atmosphere by a valve mechanism (136, 138, 140) actuated by a control rod (34) capable of bearing by way of a plunger (32) on one of the faces of a reaction disk (58) fixed to a push rod (56), the valve mechanism (136, 138, 140) possessing a shutter (138) made rigid by an insert (118) and interacting by an active part with a first valve seat (136) formed on the plunger (32) and with a second valve seat (140) formed on the piston (14), the shutter (138) being formed by a flexible tubular diaphragm (114), the active part of the shutter (138) being located between the two ends (112, 116) of the flexible tubular diaphragm (114), a stop member (152) determining simultaneously the rest position of the piston (22, 14, 102) and the rest position of the plunger (32). According to the invention, the piston (22, 14, 102) comprises, furthermore, an intermediate piston web (102) defining with the skirt (14) of the piston an annular volume (123), the first (136) and second (140) valve seats and the shutter (138) are arranged in the annular volume (123), and the second valve sheet (140) is formed on the skirt (14) of the piston.