CN2369216Y

CN2369216Y - Target flow meter

Info

Publication number: CN2369216Y
Application number: CN 99201800
Authority: CN
Inventors: 万国庆
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-01-05
Filing date: 1999-01-05
Publication date: 2000-03-15
Anticipated expiration: 2009-01-05

Abstract

The utility model discloses a novel target type flow meter, which comprises a measurement room, a target rod, a target piece, a sensor and a signal processing and display device, wherein, the lower end of the target rod runs through a hole of an upper wall of the measurement room and vertically extends into a liquid passage of the measurement room; the target piece is fixedly connected at the lower end of the target rod. The utility model is characterized in that the sensor comprises a sensor body and four stress meters; the sensor body is an upright tubular body; the upper end of the sensor body is fastened and connected with the upper end of the target rod; the lower end is fastened and connected with the measurement room; the four stress meters is abutted on the outer cylindrical surface of the sensor body. The flow meter has the advantages of simple structure, reliable performance, high measuring precision, etc.

Description

Novel target type meter

The utility model relates to a kind of liquid flow measurement instrument.

Existing target-type flow measurement instrument generally is to adopt the technical scheme of balance pivot, spring force balance, displacement-force transformation, convoluted diaphragm or sylphon seal to realize.There is following deficiency in this traditional flow measurement instrument: in displacement-force transformation process, because displacement measured value precision is low, the power precision that is conversed is also low, thereby influences the precision of flow reading; Because convoluted diaphragm or corrugated tube intensity difference, withstand voltage low, thereby serviceable life is short; The variation of working pressure causes that zero point drift is big; This class flow measurement instrument also exists complex structure, shortcoming that cost is high.

The purpose of this utility model is, a kind of novel target type meter is provided, advantage such as that this flowmeter has is simple in structure, dependable performance, measuring accuracy height, measurement range are big.

The technical solution of the utility model is: a kind of novel target type meter comprises measuring chamber, target bar, target sheet, sensor, signal Processing and display device; The lower end of described target bar is passed the hole of measuring chamber upper wall and is vertically stretched in the fluid passage of measuring chamber; Described target sheet is fixed in the lower end of target bar; It is characterized in that described sensor comprises sensor body and four strainometers; Described sensor body is a vertical tubular body, and its upper end is fastenedly connected with the upper end of described target bar, and its lower end and described measuring chamber are fastenedly connected; Described four strainometers are close on the external cylindrical surface of sensor body, are interconnected into balanced bridge, and are connected with described signal Processing and display device with lead.

When liquid flows in measuring chamber, the target sheet is produced a thrust, this thrust produces a moment of flexure by the target bar on sensor body, be close to strain gauge detection on the sensor body to the bending stress of sensor body, strain signal converts flow reading to and shows after signal Processing and display apparatus processes.This flowmeter has been abandoned the indirect dynamometry mode of the displacement-force transformation of traditional flowmeter, adopted directly survey the stress of sensor body by strainometer after, converse flow reading, there is not movable member simultaneously, thereby reliability height, measuring accuracy height, zero drift are little, and this flowmeter has also that measurement range is big, simple in structure, low cost and other advantages.

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

The balance pivot that Fig. 1 is adopted for conventional target formula flowmeter, spring force balance, displacement-force transformation metering system synoptic diagram;

Fig. 2 is the structural representation of an exemplary embodiments of the utility model target type meter;

Fig. 3 is the null-type bridge circuit of being made up of strainometer.

Traditional target type meter as shown in Figure 1 comprises target bar 2, target sheet 3 and spring 13, the lower end that target sheet 3 is connected in target bar 2 over against liquid come to, the upper end of target bar 2 is connected with spring 13, is provided with a rotating fulcrum O at the middle part of target bar 2.When flow rate of liquid was 0, the upper extreme point of target bar 2 was A, and when target sheet 3 was subjected to the liquid effects of certain flow rate, target bar 2 rotated around the O point, and the upper extreme point of target bar 2 moves to the B point.Traditional target type meter is to converse the suffered moment of flexure of target bar 2 by measuring the AB displacement, and then obtains the flow velocity of institute's fluid measured.This flowmeter is because displacement measured value precision is low, and the power precision that is conversed is also low, thereby influences the precision of flow reading.

The utility model target type meter embodiment as shown in Figure 2 comprises measuring chamber 1, target bar 2, target sheet 3, sensor 4, signal Processing and display device 5; The lower end of target bar 2 is passed the hole 7 of measuring chamber 1 upper wall and is vertically stretched in the fluid passage of measuring chamber 1; Target sheet 3 is fixed in the lower end of target bar 2; Sensor 4 comprises sensor body 8 and four strainometers 9; Sensor body 8 is a vertical tubular body, and its upper end is fastenedly connected with the upper end of target bar 2, and its lower end and measuring chamber 1 are fastenedly connected; Four strainometers 9 are close on the external cylindrical surface of sensor body 8, are interconnected into balanced bridge, and are connected with signal Processing and display device 5 with lead.

The null-type bridge circuit that strainometer is formed as shown in Figure 3, four inputs, the output terminal of this circuit are connected with signal processing apparatus 5.

As shown in Figure 2, in the present embodiment, the upper and lower end of sensor body 8 is equipped with flange arrangement 10, is provided with the flange arrangement 11 corresponding with sensor body 8 lower ends around the last cinclides 7 of measuring chamber 1, and the upper end of target bar 4 is provided with the flange arrangement 12 corresponding with sensor body 8 upper ends; Connect with bolted between each companion flange structure.Flange adds the connected mode of bolt, makes this flowmeter structure very simple, installs very conveniently, and cost greatly reduces.

As shown in Figure 2, in the present embodiment, the flange arrangement 11 around the last cinclides 7 of measuring chamber 1 upwards rises certain distance.This makes sensor 4 can not made the stable and reliable for performance of sensor by soaked with liquid in measuring process.

The utility model target type meter, employed strainometer 9 is the resistive element of a kind of resistance with suffered STRESS VARIATION, as commercially available BHF350-3AA strainometer.

Signal Processing in the utility model target type meter and display device 5 are handled the measured stress data of strainometer by signal amplification, A/D conversion and the digital operation of routine, obtain data such as current instantaneous delivery and integrated flux, and show in the pointer display mode or the liquid crystal display mode of routine.

The utility model target type meter is applicable to industrial processes automatic control system and various rate-of flow parameter measurement, is applicable to the flow metering of various medium commerce and trade clearing usefulness simultaneously.

Claims

1, a kind of novel target type meter comprises measuring chamber (1), target bar (2), target sheet (3), sensor (4), signal Processing and display device (5); The lower end of described target bar (2) is passed the hole (7) of measuring chamber (1) upper wall and is vertically stretched in the fluid passage of measuring chamber (1); Described target sheet (3) is fixed in the lower end of target bar (2); It is characterized in that described sensor (4) comprises sensor body (8) and four strainometers (9); Described sensor body (8) is a vertical tubular body, and its upper end is fastenedly connected with the upper end of described target bar (2), and its lower end and described measuring chamber (1) are fastenedly connected; Described four strainometers (9) are close on the external cylindrical surface of sensor body (8), are interconnected into balanced bridge, and are connected with described signal Processing and display device (5) with lead.

2, target type meter according to claim 1, it is characterized in that, the upper and lower end of described sensor body (8) is equipped with flange arrangement (10), the last cinclides (7) of described measuring chamber (1) is provided with the flange arrangement (11) corresponding with sensor body (8) lower end all around, and the upper end of described target bar (4) is provided with and the corresponding flange arrangement (12) in described sensor body (8) upper end; Connect with bolted between each companion flange structure.

3, target type meter according to claim 2 is characterized in that, the last cinclides (7) of described measuring chamber (1) flange arrangement (11) all around upwards rises certain distance.

4, target type meter according to claim 1 is characterized in that, the resistive element of a kind of resistance with suffered STRESS VARIATION counted in described strain.