发明名称 |
MASS FLOW CONTROLLERS AND METHODS FOR AUTO-ZEROING FLOW SENSOR WITHOUT SHUTTING OFF A MASS FLOW CONTROLLER |
摘要 |
An MFC includes: a proportional valve; a mass flow sensor; a first flow line connecting from an outlet of the proportional valve through the mass flow sensor to an exit line; a second flow line joining the first flow line at a first junction located upstream of the mass flow sensor and at a second junction located downstream of the mass flow sensor; a switching valve placed such that the switching valve can regulate a flow of a gas through the first flow line or the second flow line; and a control device connected to provide a feedback control loop for regulating the proportional valve based on signals measured by the mass flow sensor, wherein the control device includes a program for keeping a rate of a flow exiting the exit line substantially constant when the flow is through the second flow line. |
申请公布号 |
EP2817616(A4) |
申请公布日期 |
2015.11.18 |
申请号 |
EP20120869058 |
申请日期 |
2012.02.22 |
申请人 |
AGILENT TECHNOLOGIES, INC. |
发明人 |
GUAN, XIAO-SHENG;HENDERSON, ROBERT C |
分类号 |
G01N30/32;G01F25/00;G05D7/06 |
主分类号 |
G01N30/32 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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