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. 27, 2006
Filed:
Dec. 16, 2003
Tsuneo Ishigaki, Yawara-mura, JP;
Tsuneo Ishigaki, Yawara-mura, JP;
SMC Corporation, Tokyo, JP;
Abstract
A gate valve has a transfer chamber-side valve element and a process chamber-side valve element connected to a single shaft actuated with a single three-position air cylinder to selectively close a process chamber opening and a transfer chamber opening or fully open both the openings to allow an object to pass therethrough. A lever member is secured to the single shaft. A roller supported by the lever member is kept in engagement with a cam groove of a cam member. A cam support member for supporting the cam member is connected to the piston rod of the three-position air cylinder. A spring is interposed between the lever member and the cam support member. When the piston rod is in the first (lower extremity) position, both the transfer chamber-side valve element and the process chamber-side valve element fully open the transfer chamber opening and the process chamber opening, respectively. As the piston rod shifts from the first position to the second position, the roller shifts from engagement with an upper position of the cam groove to engagement with an intermediate position, causing the process chamber-side valve element to close the process chamber opening. As the piston rod shifts from the second position to the third (upper extremity) position, the roller shifts from the engagement with the intermediate position to engagement with a lower position of the cam groove, causing the transfer chamber-side valve element to close the transfer chamber opening.