Method of, and apparatus for, measuring the mass flow rate of a gas
원문보기
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
G01F-001/20
G01F-001/32
G01F-001/36
G01F-001/42
G01F-001/78
G01F-001/88
G01F-001/76
출원번호
US-0402450
(2013-05-23)
등록번호
US-9448090
(2016-09-20)
우선권정보
EP-12169386 (2012-05-24)
국제출원번호
PCT/EP2013/060688
(2013-05-23)
국제공개번호
WO2013/174956
(2013-11-28)
발명자
/ 주소
Downie, Neil Alexander
출원인 / 주소
AIR PRODUCTS AND CHEMICALS, INC.
대리인 / 주소
Zelson, Larry S.
인용정보
피인용 횟수 :
1인용 특허 :
32
초록▼
There is provided a meter for measuring the mass flow rate of a gas, the meter comprising a conduit through which the gas flows in use, the conduit having a flow restriction orifice through which choked flow occurs in use, the flow restriction orifice dividing the conduit into an upstream portion up
There is provided a meter for measuring the mass flow rate of a gas, the meter comprising a conduit through which the gas flows in use, the conduit having a flow restriction orifice through which choked flow occurs in use, the flow restriction orifice dividing the conduit into an upstream portion upstream of said orifice and a downstream portion downstream of said orifice, the meter further comprising a sensor assembly including a first piezoelectric crystal oscillator in said upstream portion such that said first piezoelectric oscillator is in contact with said gas when the meter in use, a second piezoelectric crystal oscillator in said downstream portion such that said second piezoelectric oscillator is in contact with said gas when the meter in use, said sensor assembly being arranged: to drive the first and second piezoelectric crystal oscillators such that each of the first and second piezoelectric crystal oscillators resonate at respective resonant frequencies; to measure the resonant frequency of the first piezoelectric oscillator and the resonant frequency of resonant frequency of the first piezoelectric oscillator and the the second piezoelectric oscillator; and to determine, from the resonant frequency of the second piezoelectric oscillator, the mass flow rate of gas through said orifice.
대표청구항▼
1. A method of measuring the mass flow rate of a gas through an orifice, the method using a first piezoelectric oscillator in contact with the gas upstream of the orifice and a second piezoelectric oscillator in contact with the gas downstream of the orifice and comprising; a) driving the first and
1. A method of measuring the mass flow rate of a gas through an orifice, the method using a first piezoelectric oscillator in contact with the gas upstream of the orifice and a second piezoelectric oscillator in contact with the gas downstream of the orifice and comprising; a) driving the first and second piezoelectric crystal oscillators such that each of the first and second piezoelectric crystal oscillators resonate at respective resonant frequencies;b) measuring the resonant frequency of the first piezoelectric oscillator and the resonant frequency of the second piezoelectric oscillator; andc) determining, from the resonant frequency of the first piezoelectric oscillator and the resonant frequency of the second piezoelectric oscillator, the mass flow rate of gas through said orifice. 2. A method of according to claim 1, wherein step c) further comprises: d) determining, from the resonant frequency of the first piezoelectric oscillator and the resonant frequency of the second piezoelectric oscillator, the density of gas upstream of the orifice and the density of the gas downstream of the orifice. 3. A method according to claim 2, wherein step c) further comprises: e) determining the ratio of the density of the gas upstream of the orifice to the density of the gas downstream of the orifice. 4. A method according to claim 3, wherein when the ratio is at or above a predetermined value, the flow through said orifice is determined to be choked and the mass flow rate is calculated from the density of the gas upstream of the orifice alone. 5. A method according to claim 3, wherein when the ratio is below a predetermined value, the mass flow rate is calculated from the density of the gas upstream of the orifice and from the density of the gas downstream of the orifice. 6. A method according to claim 3 wherein when the ratio is below a predetermined value, the mass flow rate is calculated from the density of the gas upstream of the orifice alone and the method further comprises the step of: f) providing a notification that the determination of mass flow rate may comprise errors. 7. A method according to claim 1, wherein the gas is dispensed from a pressure regulator or valve located upstream of the piezoelectric crystal oscillator. 8. A method according to claim 7, wherein the pressure regulator or valve is electronically controlled in response to the measured mass flow rate of gas through said orifice. 9. A meter for measuring the mass flow rate of a gas, the meter comprising a conduit through which the gas flows in use, the conduit having a flow restriction orifice through which choked flow occurs in use, the flow restriction orifice dividing the conduit into an upstream portion upstream of said orifice and a downstream portion downstream of said orifice, the meter further comprising a sensor assembly including a first piezoelectric crystal oscillator in said upstream portion such that said first piezoelectric oscillator is in contact with said gas when the meter in use, a second piezoelectric crystal oscillator in said downstream portion such that said second piezoelectric oscillator is in contact with said gas when the meter in use, said sensor assembly being arranged: to drive the first and second piezoelectric crystal oscillators such that each of the first and second piezoelectric crystal oscillators resonate at respective resonant frequencies; to measure the resonant frequency of the first piezoelectric oscillator and the resonant frequency of the second piezoelectric oscillator; and to determine, from the resonant frequency of the first piezoelectric oscillator and the resonant frequency of the second piezoelectric oscillator, the mass flow rate of gas through said orifice. 10. A meter according to claim 9, wherein the meter further comprises a drive circuit comprising a Darlington pair arranged in a feedback configuration from a common emitter amplifier. 11. A meter according to claim 9, arranged downstream of a pressure regulator or valve. 12. A meter according to claim 11, wherein the meter is arranged to control electronically the pressure regulator or valve in response to the measured mass flow rate through the flow restriction orifice. 13. A method or meter according to claim 9, wherein said piezoelectric oscillator comprises a quartz crystal oscillator. 14. A method or meter according to claim 9, wherein said piezoelectric crystal oscillator comprises at least two planar tines. 15. A computer program product executable by a programmable processing apparatus, comprising one or more software portions for performing the steps of claim 1. 16. A computer usable storage medium having a computer program product according to claim 15 stored thereon.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (32)
Funk Gary L. (Bartlesville OK) Bard William B. (Bartlesville OK), Alkylation reactor quality control.
Asoyan Karen Vartgesovich (Moscow RUX) Belonenko Vladimir Nikolaevich (Moskovskaya oblast RUX) Makeev Boris Vasilievich (Moscow RUX) Morozov Mikhail Alexeevich (Moskovskaya oblast RUX) Sarvazyan Arme, Device for excitation of oscillations and determination of properties of various fluid media.
Jones Alan R,GBX ; Webster John R,GBX ; Brown Ian D,GBX ; Pollard Duncan,GBX ; Greenough Rodney D,GBX, Method and apparatus for remotely detecting pressure, force, temperature, density, vibration, viscosity and speed of sound in a fluid.
Wiggins Robert B. (Salt Lake City UT), Quartz thickness-shear mode resonator temperature-compensated pressure transducer with matching thermal time constants o.
Livingston Peter M., Simple and inexpensive method and device for measuring concentration and rate of change of a crystal etchant gas, such as HF or DF gas.
Phelps Eric B. (Littleton CO) Cook Gary R. (Highlands Ranch CO) Roszelle Wayne O. (Littleton CO), Transient temperature compensation for pressure gauges.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.