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:
May. 18, 1999
Filed:
Sep. 26, 1997
Osamu Ogura, Okazaki, JP;
Kenichi Sato, Nagoya, JP;
Aisin Seiki Kabushiki Kaisha, Kariya, JP;
Abstract
A vehicle brake booster apparatus includes a housing, a movable wall positioned within the interior of the housing to divide the interior into a constant pressure chamber and a variable pressure chamber, a power piston connected to the movable wall for moving in response to movement of the movable wall, an axially movable input rod extending outwardly from the power piston for connection to a brake pedal, and an axially movable valve plunger mounted within the power piston and operatively connected to the input rod. A control valve is positioned within the power piston for controlling communication of the variable pressure chamber with atmospheric air. The control valve includes an air control valve and a vacuum control valve, with the air control valve including an air control seal arranged between the valve plunger and a valve body portion of the control valve. The air control seal has a radially outwardly located peripheral portion which possesses an elasticity that is greater than the elasticity of a radially inwardly located portion of the air control seal to thereby provide an effective air-tight seal.