Patent EP0200896A2 successfully refreshed from Google Patents.
EP0200896A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Digital flow meter circuit and method for measuring flow
Assignee: Badger Meter Inc
•
Filing: 1986-03-19
•
Granted: —
•
Expires: 2006-03-19
Abstract
Abstract In a methbd and apparatus (10) for generating a signal proportional to flow (V') in a pipe (11) using probes (PROBE 1 and PROBE 2) strapped onto the exterior of the pipe (11), two ultrasonic pulse trains at a carrier frequency are sent in opposite directions from one probe to the other. Two lower frequency signals are extracted from the two respective pulse trains and analyzed to detect a phase difference (Φ 21 -Φ 12 ). The phase difference (Φ 21 -Φ 12 ) corresponds to a difference in the travel times (T 21 -T 12 ) for the two pulse trains caused by the flow velocity (V') in the pipe. The two lower frequency signals are converted to digital data samples (SEQ 0 D7-DO and SEQ 1 D7-DO) which are stored with reference timing data - (TM). A microelectronic processor (16) synchronizes the two sampled waves, using the timing data (TM), before comparing the sampled waves to determine the phase difference (Φ 21 -Φ 12 ).The processor (16) and associated circuitry, also measure the travel times - (T 12 , T 21 ) of the two ultrasonic pulse trains and generate an output signal proportional to flow based on the measured phase difference (Φ 21 -Φ 12 ) and the measured travel times (T, 2 , T2,). 1
Inventors
- 👤 William H. Vander Heyden
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-10 02:00
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/66; G01F1/667
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
236 words
A method of generating a signal proportional to the rate of fluid flow (V) in an axial direction through a pipe (11), the method comprising: transmitting a first ultrasonic pulse train across the flow from a first probe (PROBE 1) to a second probe (PROBE 2); transmitting a second ultrasonic pulse train across the flow from the second probe (PROBE 2) to the first probe (PROBE 1); receiving the first and second ultrasonic pulse trains, generating a first group of sampling data (SEQ 0 D7-D0) for the first pulse train and generating a second group of sampling data (SEQ 1 D7-DO) for the second pulse train; generating timing data (TM), and associating the timing data (TM) with the first and second groups of sampling data (SEQ 0 D7-DO and SEQ 1 D7-DO); using the timing data (TM) as a reference for synchronizing the first and second groups of sampling data (SEQ 0 D7-DO and SEQ 1 D7-DO); using the sampling data (SEQ 0 D7-DO and SEQ 1 D7-DO) to determine the phase difference (Φ 21 Φ 12 ) between the respective ultrasonic pulse trains; measuring the elapsed travel times (T 12 and T2,) between transmission and reception of the ultrasonic pulse trains; and in response to the phase difference (Φ 21 Φ 12 ) and the elapsed travel times (T,2 and T 21 ), determining the flow rate (V) and generating an output signal proportional thereto.
Claim 2
Independent Claim
236 words
A method of generating a signal proportional to the rate of fluid flow (V) in an axial direction through a pipe (11), the method comprising: transmitting a first ultrasonic pulse train across the flow from a first probe (PROBE 1) to a second probe (PROBE 2); transmitting a second ultrasonic pulse train across the flow from the second probe (PROBE 2) to the first probe (PROBE 1); receiving the first and second ultrasonic pulse trains, generating a first group of sampling data (SEQ 0 D7-D0) for the first pulse train and generating a second group of sampling data (SEQ 1 D7-DO) for the second pulse train; generating timing data (TM), and associating the timing data (TM) with the first and second groups of sampling data (SEQ 0 D7-DO and SEQ 1 D7-DO); using the timing data (TM) as a reference for synchronizing the first and second groups of sampling data (SEQ 0 D7-DO and SEQ 1 D7-DO); using the sampling data (SEQ 0 D7-DO and SEQ 1 D7-DO) to determine the phase difference (Φ 21 Φ 12 ) between the respective ultrasonic pulse trains; measuring the elapsed travel times (T 12 and T2,) between transmission and reception of the ultrasonic pulse trains; and in response to the phase difference (Φ 21 Φ 12 ) and the elapsed travel times (T,2 and T 21 ), determining the flow rate (V) and generating an output signal proportional thereto.
Claim 3
Dependent Claim
39 words
The method of claim 1, wherein the digital sampling is accomplished by performing a succession of conversions of an analog signal (f D ) to digital data samples (DATA) and storing the data samples in a read/write memory (22).
Claim 4
Dependent Claim
14 words
The method of claim 2, wherein the read/write memory (22) is a first-in-first-out memory.
Claim 5
Dependent Claim
20 words
The method of claim 1, wherein the first and second ultrasonic pulse trains are transmitted by the same transmitter (14).
Claim 6
Dependent Claim
94 words
The method of claim 1, further comprising: routing the first and second ultrasonic pulse trains through a plurality of switches (15); and further comprising selectively operating the switches (15) to route the first ultrasonic pulse trains from a transmitter (14) to the first probe (PROBE 1) and to receive the first ultrasonic pulse train through the second probe (PROBE 2), and to route the second ultrasonic pulse train from the same transmitter - (14) through the second probe (PROBE 2) and to receive the second ultrasonic pulse train through the first probe (PROBE 1).
Claim 7
Dependent Claim
388 words
Apparatus (10) for connection to a pair of probes (PROBE 1 and PROBE 2), each adapted to be positioned around the circumference of a pipe (11 )-from the other, for performing the method of claim 1, the apparatus comprising: signal generating means (12, 14) for generating a first ultrasonic pulse train to be transmitted through the pipe (11) from a first one of the probes - (PROBE 1) to a second one of the probes (PROBE 2), and a second ultrasonic pulse train to be transmitted through the pipe (11) from the second one of the probes (PROBE 2) to the first one of the probes (PROBE 1); signal receiving means (20) for receiving the first and second ultrasonic pulse trains; means (15) for coupling the signal generating means and the signal receiving means to the probes; first timing means (FF-2, 25, VIA) coupled to the signal generating means (12, 14) and to the signal receiving means (20) for generating elapsed time signals that mark the time from transmission to receipt of each ultrasonic pulse train (T,Z and T21); sampling means (21, 22, 23) coupled to the signal receiving means (20) for generating and storing a first group of digital sampling data ( SEQ 0 D7-DO) for the first ultrasonic pulse train and a second group of digital sampling data (SEQ 1 D7-DO) for the second ultrasonic pulse train; second timing means (19) coupled to the signal generating means (14) and to the sampling means (21, 22, 23) to generate timing data (TM) that are associated with the digital sampling data (D7-DO) to allow synchronization of the first and second groups of digital sampling data (SEQ 0 D-7-DO and SEQ 1 D7-DO); and digital processing means (16) coupled to read the elapsed time signals (T,2 and T 2 ,) from the first timing means (FF-2, 25, VIA) and coupled to read the digital sampling data (D7-DO) and associated timing data (TM) from the sampling means (21, 22, 23), the digital processing means (16) being operable to determine flow rate (V') in response to the elapsed time signals (T ' 2 and T 21 ) and in response to the digital sampling data (D7-DO) and its associated timing data (TM), and the digital processing means (16) being further responsive to generate an output signal proportional to flow rate (V').
Claim 8
Dependent Claim
39 words
The apparatus (10) of claim 6, wherein the sampling means (21, 22, 23) includes an analog-to-digital converter (21) and memory means (22) coupled to receive and store a sequence of digital data samples from the analog-to-digital converter - (21
Claim 9
Dependent Claim
25 words
The flow meter signal processing circuit of claim 7, wherein the memory means (22) includes at least two first-in-first-out memory circuits (FIFO 1, FIFO 2).
Claim 10
Dependent Claim
91 words
The flow meter signal processing circuit of claim 6, wherein: the first and second ultrasonic pulse trains are transmitted from a single transmitting means (12, 14) and are received at a single receiving means - (20); and wherein the means for coupling the signal generating means (12, 14) and the signal receiving means (20) to the probes (PROBE 1 and PROBE 2) includes a plurality of switches that can be operated in different combinations to transmit and receive signals from either one of the two probes (PROBE 1 and PROBE 2).
Claim 11
Dependent Claim
19 words
The flow meter signal processing circuit of claim 6, wherein the digital processing means (16) is a microelectronic computer.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.