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:
Jun. 24, 1980
Filed:
Mar. 31, 1978
Hidetoshi Shimizu, Susono, JP;
Mitsuyuki Horie, Susono, JP;
Toyota Jidosha Kogyo Kabushiki Kaisha, Toyota, JP;
Abstract
A pneumatically operated brake booster comprises a hydraulic cylinder disposed within a hydraulic braking circuit connecting a master cylinder to wheel brake cylinders to increase the braking pressure trapped within the wheel brake cylinders and a servomotor for pneumatically activating the hydraulic cylinder in response to hydraulic pressure from the master cylinder. The servomotor has a spring loaded diaphgragm piston forming a negative pressure chamber and a variable pressure chamber, the former being in connection to a source of negative pressure and the latter being connected to the atmospheric pressure in response to master cylinder pressure applied to the hydraulic cylinder. The brake booster includes a control valve which is provided to selectively connect the variable pressure chamber of the servomotor to such a positive pressure source as exhaust pressure to obtain additional pressure in an emergent braking operation of the vehicle.