Patent US6314992B1 successfully refreshed from Google Patents.
US6314992B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid-switchable flow rate control system
Assignee: Tokyo Electron Ltd
•
Filing: 1999-08-09
•
Granted: 2001-11-13
•
Expires: 2019-08-09
Abstract
Abstract A fluid-switchable flow rate control system that permits free changing of the full scale flow rate and which can control a plurality of kinds of fluids with high precision. The fluid-switchable flow rate control system controls the flow rate of fluid with the pressure P 1 on the upstream side of the orifice member held about twice or more higher than the downstream pressure P 2 , the fluid-switchable flow rate control system comprising an orifice member 8 replaceable with another to provide a suitable orifice diameter according to the kind of fluid and the flow rate range, a control valve 2 provided on the upstream side thereof, a pressure detector 6 provided between the control valve 2 and the orifice member 8 , a flow rate calculation circuit 14 where from the pressure P 1 detected by the pressure detector, the flow rate Qc is calculated with the equation Qc=KP 1 (K=constant), a flow rate-setting circuit 16 for outputting flow rate setting signal Qe, a flow rate conversion circuit 18 for multiplying the calculated flow rate signal Qc by the flow rate conversion rate k into switch-over calculated flow rate signal Qf (Qf=kQc) to change the full scale flow rate, and a calculation control circuit 20 to output the difference between the switch-over calculation flow rate signal Qf and the flow rate setting signal Qe as control signal Qy to the drive 4 of the control valve 2 , thereby opening or closing the control valve to bring the control signal Qy to zero, thus controlling the flow rate on the downstream side of the orifice member.
Inventors
- 👤 Tadahiro Ohmi
- 👤 Satoshi Kagatsume
- 👤 Jun Hirose
- 👤 Kouji Nishino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:55
CPC Classifications
G; G05; G05D; G05D7/00; G05D7/06; G05D7/0617; G05D7/0629; G05D7/0635; G05D7/0641; G05D7/0658; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7758; Y10T137/7759; Y10T137/7761
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
226 words
A fluid-switchable flow rate control system which controls the flow rate of fluid with the pressure P 1 on the upstream side of the orifice member held about twice or more higher than the downstream pressure P 2 , said fluid-switchable flow rate control system comprising: an orifice member replaceable with another to provide a suitable orifice diameter according to the kind of fluid and the flow rate range, a control valve provided on the upstream side of the orifice member, a pressure detector 6 provided between the control valve and the orifice member, and a flow rate calculation circuit 14 where from the pressure P 1 detected by the pressure detector, the flow rate Qc is calculated with the equation Qc=KP 1 (K=constant), a flow rate-setting circuit for outputting flow rate setting signal Qe, a flow rate conversion circuit 18 for converting the calculated flow rate signal Qc into switch-over calculated flow rate signal Qf to change the full scale flow rate, and a calculation control circuit to output the difference between the calculated switch-over flow rate signal Qf and the flow rate setting signal Qe as control signal Qy to the drive for the control valve, thereby opening or closing the control valve to bring the control signal Qy to zero, thus controlling the flow rate on the downstream side of the orifice member.
Claim 2
Dependent Claim
226 words
A fluid-switchable flow rate control system which controls the flow rate of fluid with the pressure P 1 on the upstream side of the orifice member held about twice or more higher than the downstream pressure P 2 , said fluid-switchable flow rate control system comprising: an orifice member replaceable with another to provide a suitable orifice diameter according to the kind of fluid and the flow rate range, a control valve provided on the upstream side of the orifice member, a pressure detector 6 provided between the control valve and the orifice member, and a flow rate calculation circuit 14 where from the pressure P 1 detected by the pressure detector, the flow rate Qc is calculated with the equation Qc=KP 1 (K=constant), a flow rate-setting circuit for outputting flow rate setting signal Qe, a flow rate conversion circuit 18 for converting the calculated flow rate signal Qc into switch-over calculated flow rate signal Qf to change the full scale flow rate, and a calculation control circuit to output the difference between the calculated switch-over flow rate signal Qf and the flow rate setting signal Qe as control signal Qy to the drive for the control valve, thereby opening or closing the control valve to bring the control signal Qy to zero, thus controlling the flow rate on the downstream side of the orifice member.
Claim 3
Dependent Claim
42 words
The fluid-switchable flow rate control system as defined in claim 1 wherein the flow rate conversion circuit 18 is so configured that the calculated flow rate Qc is multiplied by conversion rate k into the switch-over calculated flow rate signal Qf (Qf=kQc).
Claim 4
Dependent Claim
31 words
The fluid-switchable flow rate control system as defined in claim 1 or claim 2 wherein the flow rate conversion circuit 18 is formed out of a dual in-line package (DIP) switch.
Claim 5
Dependent Claim
31 words
The fluid-switchable flow rate control system as defined in claim 1 wherein the flow rate conversion circuit is to regulate the amplification rate of an output amplifier of the pressure detector.
Claim 6
Dependent Claim
223 words
A fluid-switchable flow rate control system which controls the flow rate of fluid with the pressure P 1 on the upstream side of the orifice member held about twice or more higher than the downstream pressure P 2 , said fluid-switchable flow rate control system comprising: an orifice member replaceable with another to provide a suitable orifice diameter according to the kind of fluid and the flow rate range, a control valve provided on the upstream side of the orifice member, a pressure detector 6 provided between the control valve and the orifice member, a flow rate calculation circuit 14 where from the pressure P 1 detected by the pressure detector, the flow rate Qc is calculated with the equation Qc=KP 1 (K=constant), a flow rate-setting circuit 16 for outputting flow rate setting signal Qe, a flow rate conversion circuit 18 for converting the flow rate setting signal Qe into flow rate specifying signal Qs to change the full scale flow rate, and a calculation control circuit 20 to output the difference between the flow rate specifying signal Qs and the calculated flow rate Qc as control signal Qy to the drive for the control valve, thereby opening or closing the control valve to bring the control signal Qy to zero, thus controlling the flow rate on the downstream side of the orifice.
Claim 7
Dependent Claim
223 words
A fluid-switchable flow rate control system which controls the flow rate of fluid with the pressure P 1 on the upstream side of the orifice member held about twice or more higher than the downstream pressure P 2 , said fluid-switchable flow rate control system comprising: an orifice member replaceable with another to provide a suitable orifice diameter according to the kind of fluid and the flow rate range, a control valve provided on the upstream side of the orifice member, a pressure detector 6 provided between the control valve and the orifice member, a flow rate calculation circuit 14 where from the pressure P 1 detected by the pressure detector, the flow rate Qc is calculated with the equation Qc=KP 1 (K=constant), a flow rate-setting circuit 16 for outputting flow rate setting signal Qe, a flow rate conversion circuit 18 for converting the flow rate setting signal Qe into flow rate specifying signal Qs to change the full scale flow rate, and a calculation control circuit 20 to output the difference between the flow rate specifying signal Qs and the calculated flow rate Qc as control signal Qy to the drive for the control valve, thereby opening or closing the control valve to bring the control signal Qy to zero, thus controlling the flow rate on the downstream side of the orifice.
Claim 8
Dependent Claim
44 words
The fluid-switchable flow rate control system as defined in claim 5 wherein the flow rate conversion circuit 18 is so configured that the flow rate setting signal Qe is multiplied by conversion rate k into the switch-over calculated flow rate specifying signal Qs (Qs=kQc).
References Cited (Backward Citations)
US6178995B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-11-12 | 2005-05-14 | 2005-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-11-12 | 2009-05-14 | 2009-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-11-12 | 2013-05-14 | 2013-11-13 | $7700.00 | Window Closed / Lapsed |