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. 15, 2006
Filed:
May. 07, 2004
Kaoru Tsubouchi, Toyota, JP;
Nobuyuki Hirota, Nishikamo-gun, JP;
Kenichi Kobayashi, Nagoya, JP;
Advics Co., Ltd., Kariya, JP;
Abstract
A negative pressure type booster device possesses a valve mechanism constructed to compensate for insufficient depressing force applied to a brake pedal upon emergency braking. Upon depression of the brake pedal, first negative pressure valves contact first negative pressure valve seats to block a variable pressure chamber from communication with a constant pressure chamber, and an atmosphere valve seat is separated from an atmosphere valve to communicate the variable pressure chamber with atmosphere. A partition member thus moves forwards depending on the pressure difference between the chambers to output a propelling force from an output rod. When the brake pedal is stepped on quickly, a valve member is urged backwards by a spring member causing second negative pressure valve seats to contact second negative pressure valves and move the valve member backwards. The atmosphere valve separates from the atmosphere valve seat, and the variable pressure chamber quickly communicates with atmosphere.