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. 05, 1988
Filed:
Mar. 12, 1986
Wolfram Seibert, Pfungstadt, DE;
Norbert Ocvirk, Offenbach am Main, DE;
Juergen Schonlau, Niedernhausen, DE;
Guenter Trach, Offenbach am Main, DE;
Alfred Teves GmbH, Frankfurt Am Main, DE;
Abstract
A hydraulic brake system comprising a pedal-operated brake booster (5), which is connected with the master cylinder (3) and includes an auxiliary pressure supply system (13), a booster piston (4), and a booster chamber (7) wherein an auxiliary pressure is established which is proportional to the foot pressure (F). The hydraulic brake system is provided with wheel brakes (14,15,16,17) connected to the master cylinder (3), a filling stage cylinder (18) is provided which displaceably houses a two-stage piston (20). A pressure chamber (21) is arranged in front of the large stage (83) of the two-stage piston (20) and a filling chamber (22) is arranged in front of the small stage (84) of the two-stage piston (20). In this arrangement, the filling chamber (22) communicates with one of the working chambers (26) of the master cylinder (3) and/or a brake line (28) by way of a pressure line (25). The booster piston (4) plunges into an annular chamber ( 65) arranged between the master cylinder (3) and the brake booster (5). The annular chamber (65) communicates with the pressure chamber( 21) of the filling stage cylinder (18), on the one hand, and with the supply reservoir (55), on the other hand. Connected into the pressure medium path (24,80) from the annular chamber (65) to the supply reservoir (55), to this end, is a valve (79) operable by the pressure in the booster chamber (7). In one of its positions, the valve (79) blocks the pressure medium passage towards the supply reservoir (55). Thus, upon the braking operation, the valve (79) permits the pressure medium to flow from the annular chamber (65) into the pressure chamber (21) of the filling stage cylinder (18) and in its other position the valve (79) connecting the annular chamber (65) with the supply reservoir (55).