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. 19, 2003
Filed:
Feb. 01, 2002
John E. Mackiewicz, Niles, MI (US);
Raymond Kosarski, Jr., Niles, MI (US);
Robert Bosch Corporation, Broadview, IL (US);
Abstract
A master cylinder ( ) including a housing ( ) with a bore ( ) for retaining a piston assembly ( ) to define a first chamber ( ) that is connected to wheel brakes ( ′) in a first brake circuit and a second chamber ( ) that is connected to wheel brakes ( ′) in a second brake circuit. The piston assembly ( ) includes a sleeve ( ) and a concentric cylindrical body ( ) whose respective first and second end surface areas define a first effective area (D ) while the second end surface area of the cylindrical body ( ) defines a second effective area (D ) within the bore ( ). A valve ( ) activated by axial movement of an input member ( ) allows operational hydraulic fluid to be simultaneously communicated to the wheel brakes ( ′) and the first chamber ( ) where the operational hydraulic fluid acts on the first effective area (D ) to move the piston assembly ( ) and pressurize fluid in the second chamber ( ) to develop pressurized fluid that is communicated to wheel brakes ( ′) to complete a first brake application. In an absence of operational hydraulic fluid in the first chamber ( ), a manual input acts on the cylindrical (body ) to move the second effective area (D ) into the second chamber ( ) and pressurize fluid therein to initiate a second brake application.