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:
Mar. 05, 1991
Filed:
Dec. 12, 1989
Junichi Ohki, Higashimatsuyama, JP;
Atushi Satoh, Higashimatsuyama, JP;
Jidosha Kiki Co., Ltd., Tokyo, JP;
Abstract
In the negative pressure booster equipment 1 according to the present invention, a groove 27 is provided on the inner peripheral beads 14a and 16a of the diaphragms 14 and 16, fixed on the valve body 8 and forming the power pistons in order to communicate the variable pressure chambers 5b and 7b divided by the diaphragms 14 and 16 with the passages 26 and 28 corresponding to the variable pressure chambers 5b and 7b. Accordingly, the air passages are opened to the variable pressure chambers 5b and 7b through the groove 27 formed on the beads 14a and 16a of the diaphragms 14 and 16. According to this invention, therefore, there is no need to provide wide gap between the fixed portion of the beads and the center plate in order to open the air passages to the variable pressure chambers. This makes it possible to shorten overall length of the negative pressure booster equipment 1.