CN114383675A - Ultrasonic water meter with pressure detection function - Google Patents
Ultrasonic water meter with pressure detection function Download PDFInfo
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- CN114383675A CN114383675A CN202210001038.5A CN202210001038A CN114383675A CN 114383675 A CN114383675 A CN 114383675A CN 202210001038 A CN202210001038 A CN 202210001038A CN 114383675 A CN114383675 A CN 114383675A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
- G01F1/662—Constructional details
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
- G01F1/667—Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
- G01M3/28—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds
- G01M3/2807—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds for pipes
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
- G01M3/28—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds
- G01M3/2807—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds for pipes
- G01M3/2815—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds for pipes using pressure measurements
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Electromagnetism (AREA)
- Measuring Volume Flow (AREA)
Abstract
The invention relates to the technical field of water metering, and discloses an ultrasonic water meter with pressure detection. The matching layer structure is firstly installed on the main body structure, then the communication PCB is fixed on the matching layer structure, the metering PCB is inserted on the communication PCB, and finally the upper shell structure is connected with the main body structure. The water meter is internally provided with basic units of an ultrasonic transducer and a pressure sensor, so that the small-caliber water meters (DN 15, 20 and 25) can accurately acquire the temperature, pressure, flow velocity and flow information of domestic water in the pipeline, provide data for detecting the leakage of a pipe network and positioning, and solve the problem of analyzing the leakage of the small-caliber pipe network of the water distribution network.
Description
Technical Field
The invention relates to the technical field of water metering, in particular to a small-size ultrasonic water meter capable of collecting pressure, temperature, flow velocity and flow.
Background
A water meter is a meter that measures water flow. At present, the metering mode of the mainstream water meter is the traditional mechanical water meter. However, the gear of the mechanical water meter is worn for a long time, which affects the metering accuracy. For meters installed outdoors, the gears are exposed to the sun and rain for a long time and are in a high-temperature state, so that deformation and aging are caused, and the metering accuracy is greatly reduced. In addition, in the area of poor quality of water, the water gauge can lead to gear lock-up because of stone, silt, and then lead to normally not measuring even damage. Aiming at the problems of the mechanical meter, the ultrasonic water meter with the pressure detection function has no mechanical movable part, and can not have the problems that the metering precision is reduced due to the abrasion of the gear and the meter cannot be metered due to the fact that the gear is locked up due to the stones and the silt.
The running, the overflowing, the dripping and the leakage of a water distribution network are the pain problems of the water supply industry. According to the investigation of China's town water supply society, water distribution networks are cultivated in more than 60 hundred million meters each year due to water leakage. In addition, the unbalanced water supply pressure of the water distribution network not only causes poor water use experience of users, but also causes waste of power resources, and increases the water supply cost of water service companies. In the current meter market, the vast majority of water meters with pressure detection are DN50 and large-caliber water meters above the DN, and the pressure and temperature detection function for DN15, DN20 and DN25 small-caliber water meters is not available. In addition, in order to detect the pressure of the pipe network, many water utilities need to purchase expensive pressure sensors, which further increases the operation cost of the pipe network. Aiming at the problems, the ultrasonic water meter with the pressure detection function is integrated in the water meter through the piezoelectric ceramic and the piezoresistive strain gauge, so that the temperature and pressure measuring functions of the DN15, 20 and 25 small-caliber ultrasonic water meter are realized, and the problem of pipe network leakage of a water distribution network is further positioned through analyzing temperature and pressure data.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides an ultrasonic water meter with pressure detection, which comprises a metering PCB (printed circuit board), a communication PCB, a main body structure, an upper shell structure and a matching layer structure. The water meter is internally provided with an ultrasonic transducer basic unit, a piezoelectric ceramic and pressure sensor basic unit and a piezoresistance strain gauge, so that the small-caliber water meters (DN 15, 20 and 25) can accurately acquire the temperature, pressure, flow speed and flow information of domestic water in a pipeline, provide data for detecting pipe network leakage and positioning pipe network leakage points, report the acquired information through remote communication, and solve the problem of analysis of the small-caliber pipe network leakage of a water distribution network.
The purpose of the invention can be realized by the following technical scheme:
the utility model provides an ultrasonic water meter with pressure measurement, includes measurement PCB board, communication PCB board, major structure, epitheca structure, matching layer structure, wherein:
measuring a PCB (printed Circuit Board): the device comprises an MCU master control circuit, an NFC circuit, an IR circuit, a key circuit, a pressure detection circuit and an ultrasonic metering circuit;
communication PCB board: comprises a communication circuit and a battery circuit;
a body structure; the upper shell structure is used for wrapping and protecting the metering PCB, the communication PCB and the matching layer structure and is connected with an external water pipe;
the upper shell structure: connecting the main body structure and displaying parameter information of the water meter;
matching layer structure: installing an ultrasonic transducer and a pressure sensor;
the connection relationship is as follows: the matching layer structure is firstly installed on the main body structure of the water meter, then the communication PCB is fixed on the matching layer structure, the metering PCB is inserted on the communication PCB, and finally the upper shell structure is connected with the main body structure.
Further, the connection mode of the main body structure and the upper shell structure is screw fixation, thread screwing and glue filling sealing, and preferably, glue filling fixation is selected.
Furthermore, the main body structure and the matching layer structure are connected in a laser and hot plate welding mode without screw fixation.
Further, the matching layer structure mounts 1 pressure sensor, 2 ultrasonic transducers, and 2 mirrors.
Furthermore, the battery circuit on the communication PCB board has two batteries, wherein one battery supplies power for the MCU main control circuit, the NFC circuit, the IR circuit, the key circuit, the pressure detection circuit and the ultrasonic metering circuit, and the other battery supplies power for the communication circuit.
Furthermore, the metering PCB adopts U-shaped row nuts, and the production process of the PCB single-panel is realized.
Further, the communication PCB board is connected with 2 ultrasonic transducers and 1 pressure sensor of the matching layer through elastic pins or springs in a fastening mode of the matching layer structure.
Furthermore, the MCU main control circuit of the metering PCB analyzes pressure parameters collected by the pressure detection circuit and sound velocity information collected by the ultrasonic transducer, detects front and back leakage of the water meter, and can position the quantity and position of front leakage of the water meter.
Furthermore, the main body structure and the matching layer structure are connected to form a pipeline without diameter shrinkage.
Furthermore, the ultrasonic transducer is realized by bonding the outer wall of the matching layer by using piezoelectric ceramics.
Furthermore, the pressure sensor and the matching layer are connected in an embedded mode and are arranged in the middle of the 2 transducers, and the metal surface of the pressure sensor is used as a reflector of the ultrasonic transmission channel.
Furthermore, the communication between the communication circuit and the MCU master control circuit adopts a level conversion mode.
Further, the NFC circuit can store the information of the accumulated flow, and the stored information can be read by a meter reading device when the battery circuit is dead.
Further, the MCU master control circuit determines the quantity and the position of leakage in the water distribution network by adopting a calibration method, and further, a Genetic Algorithm (GA) and an Ant Colony Optimization (ACO) are selected to establish a pipe network leakage analysis model.
Furthermore, the calibration method is used for establishing a model to determine the leakage point and the position by analyzing parameters such as the acquisition pressure and the flow rate of the ultrasonic water meter in the water distribution network, the caliber of the ultrasonic water meter, the Hazen-Williams coefficient and the like.
The invention has the beneficial technical effects that: the DN15, 20 and 25 small-caliber water meters are reduced in size through the built-in ultrasonic transducer basic unit, the piezoelectric ceramic and pressure sensor basic unit and the piezoresistive strain gauge, and can acquire information such as pressure, temperature, flow speed and flow, so that data support is provided for small-caliber pipe network leakage analysis of a water distribution network, the performance and function requirements of a third-generation intelligent water meter are met, and waste of water resources is avoided.
Drawings
Figure 1 is a schematic view of a water meter configuration of the present invention;
FIG. 2 is a schematic illustration of the metering principle of the present invention;
FIG. 3 is a schematic diagram of the overall circuit of the present invention;
fig. 4 is a top view of the water meter body structure of the present invention in connection with the mating layer structure.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.
As shown in fig. 1, an ultrasonic water meter with pressure detection includes a measurement PCB, a communication PCB, a main structure, an upper shell structure, and a matching layer structure. The main structure of the water meter is made of high-strength, healthy and environment-friendly polymer plastic materials through injection molding and is connected with a pipeline of a water distribution network through threads; as shown in fig. 4, the matching layer structure is connected with the main body structure of the water meter by means of hot plate or laser welding to form a closed pipeline of the water meter (containing three sizes of DN15, 20 and 25) meeting the national standard; the matching layer structure is formed by connecting a basic unit forming the ultrasonic transducer, namely piezoelectric ceramics, a basic unit forming the pressure sensor, namely a piezoresistive strain gauge, a metal reflector and a high-strength plastic structure, wherein the piezoelectric ceramics and the plastic of the matching layer structure are in an adhesion mode, and the pressure sensor and the plastic of the matching layer structure are in an insert injection molding mode; the communication PCB is connected with the matching layer structure through a buckle on the matching layer structure, comprises a battery circuit and a communication circuit, and simultaneously collects sensor signals on the matching layer structure and uploads the sensor signals to the metering PCB; the communication PCB is connected with the sensor of the matching layer structure through elastic structural components such as a spring, an elastic needle and the like; the metering PCB is connected with the communication PCB in a plug-in mode, so that information interaction is realized, wherein the metering PCB is a U-shaped socket, and the communication PCB is a pin header; the communication PCB comprises an MCU master control circuit, an NFC circuit, an IR circuit, a key circuit, a pressure detection circuit and an ultrasonic metering circuit; the grooving openings of the metering PCB and the communication PCB correspond to the guide rails of the main structure of the water meter, and the PCB is accurately placed into the main structure of the water meter through a robot arm; the sealing effect of the IP68 grade is realized between the upper shell structure and the water meter main body structure through a thread or glue pouring mode; the upper shell structure is provided with a transparent and ultraviolet-proof window of liquid crystal display and a transparent window of infrared communication; meanwhile, the national standard requires information such as Q value, R value, temperature grade and the like to be marked on the upper shell structure panel of the water meter.
As shown in fig. 2, the first reflector (4) and the third reflector (5) of the ultrasonic wave are positioned at the concave part inside the pipeline, so that the ultrasonic pipeline is straight without reducing diameter, and the pressure loss of the ultrasonic water meter is greatly reduced; the pressure sensor (3) is positioned on the matching layer structure and is used as an ultrasonic second reflector; as shown in figure 4, the ultrasonic first transducer (1) is formed by bonding piezoelectric ceramics (6) on one side of a matching layer structure, the ultrasonic second transducer (2) is formed by bonding piezoelectric ceramics (7) on one side of the matching layer structure, and the pressure sensor (3) is embedded and injected inside the matching layer structure.
The ultrasonic wave metering principle is that a first ultrasonic wave transducer (1) sends signals, the signals are reflected to a second ultrasonic wave transducer (2) through a first reflector (4), a second reflector and a third reflector (5) to be received, and the time for transmitting sound waves at the moment is recorded as QUOTE
(ii) a On the contrary, the ultrasonic wave second transducer (2) sends signals, and the signals are reflected to the first reflector (5), the second reflector and the third reflector (4)The ultrasonic first transducer (1) receives the ultrasonic wave and records the time taken for transmitting the ultrasonic wave at the moment as QUOTE
The distance between the ultrasonic second transducer (1) and the ultrasonic second transducer (2) is L.
At a fixed reference temperature, the ultrasonic wave has a known transit speed c in water, QUOTE
And QUOTE
QUOTE, which can be calculated from the formulae (1) and (2), respectively
And QUOTE
Difference of QUOTE
Called the delta ToF can be calculated from equation (3) by simultaneousThe flow rates obtained by the formula (1) and the formula (2) are shown in the formula (4); furthermore, the flow can be obtained by obtaining the linear velocity of a certain point (along the sound path direction) in the pipeline through the transmission of ultrasonic waves and integrating all the linear velocities in the pipeline on the sectional area of the pipeline, and the accumulated flow of the water meter can be obtained by further accumulating according to the flow which passes through a certain time, so that the metering function of the water meter is realized.
 |
Formula (1) |
 |
Formula (2) |
 |
Formula (3) |
 |
Formula (4) |
According to the change relation between the temperature and the sound velocity and the ultrasonic wave metering principle, the temperature can be obtained through sound velocity calculation, and the sound velocity is calculated according to the following formula (5).
 |
Formula (5) |
The trend of the sound velocity with temperature calculated according to the Bilaniuk and Wong equations (point 148) can be further used to obtain the measured temperature from the sound velocity calculated by equation (5).
From the above information, the key point of the ultrasonic water meter with pressure detection for calculating the flow rate, flow, temperature and accumulated flow is to collect QUOTE
And QUOTE
Therefore, the MSP430FR6007 of TI is used as a control chip of the MCU master control circuit, and the USS module in the chip can acquire the signal of the ultrasonic transducer to calculate to obtain QUOTE
And QUOTE
。
The ultrasonic metering circuit consists of two pairs of resistance-capacitance matching circuits connected in parallel and is used for connecting an MSP430FR6047 chip in the MCU master control circuit to perform impedance matching and signal extraction with the ultrasonic transducer sensor.
The principle of pressure detection is that a piezoresistive strain gauge in a pressure sensor can sense water pressure to cause small deformation of metal on the surface of the sensor, so that the resistance value of the sensor is changed, and a resistance change conversion bit voltage signal of the sensor is transmitted to an ADC pin of an MSP430FR6007 chip of an MCU main control circuit through a pressure detection circuit; the pressure detection circuit consists of two stages of operational amplifiers, wherein a first stage operational amplifier connected with the pressure sensor adopts an OPA2991 chip to form a trans-impedance amplifier (TIA) to convert current change caused by resistance value change into a bit voltage signal, and a second stage operational amplifier adopts an OPA177 chip to form a voltage amplifier circuit to amplify a weak voltage signal output by the first stage operational amplifier to the MCU main control circuit; the MSP430FR6007 chip further calculates the pressure information of the water meter pipe wall according to the acquired voltage signal.
As shown in fig. 3, the MCU master control circuit, the NFC circuit, the IR circuit, the key circuit, the pressure detection circuit, and the ultrasonic measurement circuit device are located on a measurement PCB (the schematic diagram of the PCB is shown in fig. 1); the communication circuit and the battery circuit are positioned on a device metering PCB (a PCB schematic diagram is shown in figure 1); one battery in the battery circuit supplies power to the MCU master control circuit, the NFC circuit, the IR circuit, the key circuit, the pressure detection circuit and the ultrasonic metering circuit, and the other battery supplies power to the communication circuit; the communication circuit is compatible with MBUS, RS485, LoRa and NB-IoT communication modes and is indirectly or directly accessed to an AMR/AMI system platform of water service; (ii) a The MCU main control circuit analyzes the acquired sensor data to calculate information such as flow speed, flow, temperature, pressure and the like and displays the information through the liquid crystal circuit; the IR circuit and the NFC circuit are maintenance channels of a water meter in a local communication mode, wherein when the metering battery is dead, the local acquisition equipment can also read the last water meter metering information through NFC.
The invention realizes the ultrasonic water meter with pressure detection, can integrate the pressure sensor in the small-caliber water meter, accurately collects the temperature, pressure, flow velocity and flow information of domestic water in the pipeline, provides data for detecting the leakage of a pipe network and positioning, and solves the problem of analyzing the leakage of the small-caliber pipe network of the water distribution network.
The above-mentioned embodiments are illustrative of the specific embodiments of the present invention, and are not restrictive, and those skilled in the relevant art can make various changes and modifications to obtain corresponding equivalent technical solutions without departing from the spirit and scope of the present invention, so that all equivalent technical solutions should be included in the scope of the present invention.
Claims (10)
1. The utility model provides an ultrasonic water meter with pressure measurement which characterized in that, includes measurement PCB board, communication PCB board, major structure, epitheca structure, matching layer structure, its connection is: match layer structure and install earlier at the major structure, fix the communication PCB board at matching layer structure again, measure the PCB board and peg graft on the communication PCB board, be connected upper shell structure and major structure at last, wherein:
the metering PCB board comprises an MCU master control circuit, an NFC circuit, an IR circuit, a key circuit, a pressure detection circuit and an ultrasonic metering circuit;
the communication PCB board comprises a communication circuit and a battery circuit;
the main body structure is connected with the upper shell structure, the metering PCB, the communication PCB and the matching layer structure are wrapped and protected, and the main body structure is connected with an external water pipe;
the upper shell structure is connected with the main body structure and used for displaying parameter information of the water meter;
the matching layer structure is used for mounting the ultrasonic transducer and the pressure sensor.
2. An ultrasonic water meter with pressure measurement as set forth in claim 1, wherein said main body structure is connected to said upper housing structure by a glue-filled sealing connection.
3. The ultrasonic water meter with pressure detection as claimed in claim 1, wherein the main structure and the matching layer structure are connected by laser and hot plate welding without screws; and the pipelines formed by connection have no diameter shrinkage.
4. An ultrasonic water meter with pressure sensing as set forth in claim 1, wherein said matching layer structure includes 1 pressure sensor, 2 ultrasonic transducers and 2 mirrors.
5. An ultrasonic water meter with pressure detection as claimed in claim 1, wherein the battery circuit on the communication PCB board has two batteries, wherein one battery supplies power to the MCU master control circuit, the NFC circuit, the IR circuit, the key circuit, the pressure detection circuit, and the ultrasonic metering circuit, and the other battery supplies power to the communication circuit.
6. An ultrasonic water meter with pressure detection function as claimed in claim 1, wherein the communication PCB is fastened to the matching layer and connected to 2 ultrasonic transducers and 1 pressure sensor of the matching layer via elastic pins or springs.
7. The ultrasonic water meter with pressure detection of claim 1, wherein the MCU master control circuit of the metering PCB analyzes the pressure parameters collected by the pressure detection circuit and the sound velocity information collected by the ultrasonic transducer to detect the front and back leakage of the water meter and to locate the amount and position of the front leakage.
8. An ultrasonic water meter with pressure measurement as set forth in claim 4, wherein said ultrasonic transducer is implemented by bonding a matching layer outer wall with a piezoelectric ceramic.
9. An ultrasonic water meter with pressure detection function as claimed in claim 4, wherein the pressure sensor is connected to the matching layer by means of an insert and is placed at the middle position of 2 transducers, and the metal surface of the pressure sensor is used as a reflector for the ultrasonic transmission channel.
10. An ultrasonic water meter with pressure measurement as set forth in claim 5, wherein the NFC circuit stores cumulative flow information, and the stored information is readable by a meter reading device when the battery circuit is dead.
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| CN202210001038.5A CN114383675A (en) | 2022-01-04 | 2022-01-04 | Ultrasonic water meter with pressure detection function |
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| CN202210001038.5A CN114383675A (en) | 2022-01-04 | 2022-01-04 | Ultrasonic water meter with pressure detection function |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116026437A (en) * | 2023-03-29 | 2023-04-28 | 青岛鼎信通讯科技有限公司 | NFC communication-based ultrasonic water meter calibration method |
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2022
- 2022-01-04 CN CN202210001038.5A patent/CN114383675A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116026437A (en) * | 2023-03-29 | 2023-04-28 | 青岛鼎信通讯科技有限公司 | NFC communication-based ultrasonic water meter calibration method |
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