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:
Jan. 30, 2001
Filed:
Dec. 28, 1999
Isao Suzuki, Tokyo, JP;
MKS Japan, Inc., Tokyo, JP;
Abstract
An actuator utilizing the pressure of a gas is used to operate a diaphragm-operated control valve. An operating force generated by the actuator is varied by feeding and discharging a gas such as N,through a narrow metallic tube. This is conducted by remote control, by means of electromagnetic valves provided in an environment at room temperature. The state of the control valve is monitored by a flow rate sensor which detects an actual flow rate of a fluid being controlled. Based on a signal representative of the detected actual flow rate, the electromagnetic valves for the actuator are controlled so that the fluid always flows at a desired flow rate. The gas such as N,is heated by a heat exchanger in a high-temperature atmosphere in the vicinity of the actuator, to thereby prevent cooling of the fluid being controlled.