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. 12, 2018
Filed:
Oct. 07, 2014
Fujikura Rubber Ltd., Koto-ku, Tokyo, JP;
Fujikin Incorporated, Osaka-shi, Osaka, JP;
FUJIKURA RUBBER LTD., Tokyo, JP;
Fujikin Incorporated, Osaka, JP;
Abstract
A multistage piston actuator exerts a driving pressure against a spring pressure into pressure chambers of piston bodies, fitted into a cylinder body, to operate the push rod. Each piston body is combined with a partition fitted into the cylinder body. Each piston body includes a pressure receiving plate portion, and an axial rod and a slidable cylindrical guide portion extending concentrically in opposite directions, the axial rod having an axial air passage connected to the pressure chambers. Each partition includes a base plate portion having a through-hole which receives the axial rod of an adjacent piston body, a large-diameter outermost cylindrical portion fitted into the cylinder body, and a slidable cylindrical guide portion slidably fit-engaged with the slidable cylindrical guide portion of the piston body. The axial rods of each piston body are brought into contact to operate the push rod.