CN201034643Y

CN201034643Y - Venturi type differential pressure liquid flowmeter

Info

Publication number: CN201034643Y
Application number: CNU2007200624335U
Authority: CN
Inventors: 刘志壮
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-02-02
Filing date: 2007-02-02
Publication date: 2008-03-12
Anticipated expiration: 2017-02-02

Abstract

The utility model relates to a liquid flow meter, in particular to a venturi differential pressure liquid flow meter, which is widely used in the precise measure and automatic control of the medical, industry, agriculture, and chemical industries. An input tube 1, a laryngeal tube 2, and an output tube 3 are communicated to each other in series. The input tube 1 and the laryngeal tube 2 extend an additional pipe respectively, which are the pressure taking additional pipe 4 of the input terminal and the pressure taking additional pipe 5 of the laryngeal tube connecting to the differential pressure sensor 6. The joint 7 of differential pressure sensor binding post is connected to the amplify circuit, and then the amplify circuit is connected to the display instrument. The utility model has a simple structure, stable performance, a simple handler circuit, and two-way measure of flow. The utility model can be designed into a micro-measure flow meter. The performance of the complete appliance is reliable and the sensitivity and the measurement accuracy are high, which is suitable to be designed into a liquid current rate and liquid flow meter with different ranges.

Description

Venturi type differential pressure liquid flowmeter

Technical field the utility model relates to a kind of liquid flowmeter, particularly a kind of flow range extendability well, a kind of venturi type differential pressure liquid flowmeter of energy measurement volume flow rate, mass flowrate, flow velocity and bidirectional measuring.Be widely used in the liquid accurate measurement and the automation field of industries such as medical science, industry, agricultural, chemical industry.

The background technology liquid flowmeter is used very extensive, its structure and of a great variety, but most structure is complicated.Design and making trouble the more important thing is that the liquid flowmeter of low discharge, tiny flow quantity does not have a kind of venturi type differential pressure liquid flowmeter at home.

Provide summary of the invention order of the present utility model a kind of extendability better, venturi type differential pressure liquid flowmeter that can the large and small different flow of bidirectional measurement.

The technical scheme that the utility model adopted is: the utility model is made up of input pipe 1, efferent duct 3, trunnion 2, input end pressure arm 4, trunnion pressure arm 5, differential pressure type pressure transducer 6, voltage modulate circuit, AD converter and microprocessor or numeral, analog secondary instrument (owing to be prior art, Gu Tuzhong does not draw).Input pipe 1, trunnion 2 and efferent duct 3 are communicated with successively, it is that input end pressure arm 4, trunnion pressure arm 5 are connected with differential pressure type pressure transducer (6) that input pipe 1, trunnion 2 are respectively told an arm, the connection terminal joint 7 of differential pressure type pressure transducer connects amplifying circuit, and amplifying circuit connects Displaying Meter again.

Input pipe

1,3 one-tenth in-lines of trunnion 2 and efferent duct or bend to certain angle and be connected.The internal diameter of input pipe 1 and efferent duct 3 can be identical, also can be different.

The beneficial effects of the utility model are: pressure sensor structure is simple, cheap, function admirable, and the linearity is good; Can be designed to the tiny flow quantity meter, the range ability favorable expandability can be carried out bidirectional measurement; The complete machine dependable performance, highly sensitive, the measuring accuracy height, measuring relative errors is in 1%; Be particularly suitable for being designed to liquid or the gas flow rate and the flowmeter of different ranges.

Description of drawings

Below in conjunction with drawings and Examples the utility model is further specified

Accompanying drawing is the utility model structural representation.

Among the figure: 1. input pipe 2. trunnions 3. efferent ducts 4. input end pressure arms 5. trunnion pressure arms 6. differential pressure type pressure transducers 7. connection terminal joints

Embodiment

Referring to accompanying drawing, a kind of venturi type differential pressure liquid flowmeter is made up of input pipe 1, efferent duct 3, trunnion 2, input end pressure arm 4, trunnion pressure arm 5, differential pressure type pressure transducer 6, voltage modulate circuit, AD converter and microprocessor or numeral, analog secondary instrument (owing to be prior art, Gu Tuzhong does not draw).Input pipe 1, trunnion 2 and efferent duct 3 are communicated with successively, the diameter of trunnion 2 is less than the diameter of input pipe 1, efferent duct 3, it is that input end pressure arm 4, trunnion pressure arm 5 are connected with differential pressure type pressure transducer (6) two pressure taps that input pipe 1, trunnion 2 are respectively told an arm, the connection terminal joint 7 of differential pressure type pressure transducer connects amplifying circuit, and amplifying circuit connects Displaying Meter again.

Input pipe

1,3 one-tenth in-lines of trunnion 2 and efferent duct or bend to certain angle and be connected.The internal diameter of input pipe 1 and efferent duct 3 can be identical, also can be different.The principle of venturi type differential pressure liquid flowmeter: when flow of liquid is crossed input pipe 1, trunnion 2, efferent duct 3, because the throttling hypotensive effect of trunnion 2, the velocity ratio of trunnion 2 is bigger, and pressure ratio is less, make the pressure of the pressure of input pipe 1 greater than trunnion 2, and pressure differential is directly related with flow, and the big more differential pressure of flow is big more, and the more little differential pressure of flow is more little.The differential pressure type pressure transducer changes the variation that converts voltage to pressure differential, output after voltage amplifier amplifies and handles accordingly.Gained voltage send the aanalogvoltage table to show or send modulus (A/D) change-over circuit, send single-chip microcomputer to handle and demonstration again.Change the range ability of this liquid flowmeter by the big I of revising input pipe 1, trunnion 2 and efferent duct 3.Utilize the structure of this venturi type differential pressure liquid flowmeter and principle can be used for the flow of measurement gas.Input pipe 1, trunnion 2, efferent duct 3, input end pressure arm 4 and trunnion pressure arm 5 can be made with plastics, glass or metal tube, and also available other material is made.When liquid from input pipe 1, trunnion 2 and efferent duct 3 by the time, by continuity equation and Bernoulli equation principle as can be known, the flow velocity of liquid is greater than the flow velocity of liquid in the input pipe 1 in the trunnion 2; The pressure of trunnion 2 is less than the pressure in the input pipe 1, and the pressure differential of fluid flow in input pipe 1 and trunnion 2 is just big, and definite quantitative relation is arranged.The pressure reduction of input pipe 1, trunnion 2 detects by being sent to differential pressure type pressure transducer 6 by input end pressure arm 4 and trunnion pressure arm 5 respectively, and is converted to the correspondent voltage signal, output after voltage amplifier amplifies and handles accordingly.Gained voltage send the aanalogvoltage table to show or send analog to digital conversion circuit (A/D change-over circuit), send single-chip microcomputer to handle and demonstration again.

Claims

1. venturi type differential pressure liquid flowmeter, comprise input pipe (1), trunnion (2) and efferent duct (3), it is characterized in that: input pipe (1), trunnion (2) and efferent duct (3) are communicated with successively, it is that input end pressure arm (4), trunnion pressure arm (5) are connected with differential pressure type pressure transducer (6) that input pipe (1), trunnion (2) are respectively told an arm, the connection terminal joint (7) of differential pressure type pressure transducer connects amplifying circuit, and amplifying circuit connects Displaying Meter again.

2. venturi type differential pressure liquid flowmeter according to claim 1 is characterized in that: the internal diameter of input pipe (1) and efferent duct (3) can be identical, also can be different.

3. venturi type differential pressure liquid flowmeter according to claim 1 is characterized in that: input pipe (1), trunnion (2) become in-line or bend to certain angle to be connected with efferent duct (3).