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. 30, 2002
Filed:
Mar. 21, 2001
Toshio Takayama, Yamanashi-ken, JP;
Kunihiro Matsunaga, Yamanashi-ken, JP;
Takuya Obata, Yamanashi-ken, JP;
Tokico, Ltd., , JP;
Abstract
The present invention provides a brake booster that, although simple in construction, capable of adjusting the braking force derived by operation of a solenoid mechanism without worsening the braking response. In the brake booster according to the present invention, when a movable member ( ) is shifted toward the rear side by electromagnetic force of a solenoid ( ), the shifting movement is transmitted to a valve seat member ( ) through pins ( ) to open an atmospheric valve ( ) through which air is introduced into a variable pressure chamber ( ), whereby a pressure difference is created between the variable pressure chamber and a constant pressure chamber and generates booster output (thrust output force). In the present invention, pressure in the constant pressure chamber is introduced into a chamber ( ) formed at one end of the movable member ( ) through a passage ( ), and atmosphere is introduced into a chamber ( ) formed at the other end of the movable member ( ) through a passage ( ), thereby exerting on the movable member ( ) a reaction force caused by the pressure difference between the variable pressure chamber and the constant pressure chamber. Thus, the booster output becomes proportional to the electric current supplied to the solenoid ( ). Further in the present invention, the size of the passage ( ) is determined properly so as to limit air introduced therethrough into the chamber ( ) and keep the reaction force small until the booster output reaches an adequately level, thereby preventing the breaking response from deteriorating.