CN2474997Y

CN2474997Y - Standard air quantity measuring sensor

Info

Publication number: CN2474997Y
Application number: CN 01218162
Authority: CN
Inventors: 张庆
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-04-01
Filing date: 2001-04-01
Publication date: 2002-01-30
Anticipated expiration: 2011-04-01

Abstract

A standard air quantity measuring transducer has the structure that two parallel balance tubes are arranged in the direction of a perpendicular flange. A plurality of small holes with grooves are arranged on the balance tubes, which install the transducer in an airway with solidness and precision through the flange and a guide rail. Through the measurement of the measuring holes and the balancing of the balance tubes, a differential pressure speed-variator transforms the pressure signals into electrical signals, and then a flow meter processes the electrical signals to achieve the goal of highly precise automatic monitoring. The standard air quantity measuring transducer can realize gridded method measurement with high precision, simple structure and reliable performance, can be installed and maintained when a fan is in operation, thereby having great values of popularization and application.

Description

Standard air measuring sensor

The utility model relates to a kind of air measuring sensor, especially a kind of standard air measuring sensor.

At present, the air measuring sensor is broadly divided into two big classes: a class is a throttle type, as venturi, wing etc., another kind of is non-throttle type, as backing tube, bourdon's tube, in above-mentioned two class devices, the former generally is applied in the lower air channel of wind speed, by throttling the dynamic pressure signal is amplified to improve measuring accuracy, but its shortcoming is: throttling increases the energy loss of duct resistance and gas flow to cause blower fan exert oneself reductions, power consumption increase, when serious even influence ordinary production, though bourdon's tube, backing tube are simple in structure, measuring accuracy is lower.These devices are non-standard measurement mechanism, and flow coefficient k is a nonlinear relationship with the gas flow rate of surveying.Just because of traditional measurement mechanism exists various deficiencies, so the speed measuring device that disposes on air channel, blower fan or other equipment mostly is removed or stops using a few years ago.

The utility model proposes a kind of standard air measuring sensor, it is low that it can effectively solve precision, makes the installation cost height, and flow coefficient k is a nonlinear relationship with the working medium flow of surveying, and can't realize the difficult problem of industrial automation monitoring.

The purpose of this utility model is achieved in that inner flange (1) is connected with outside flange (2) by bolt, on inner flange (1) face, by fixture splice (3) perpendicular to inner flange (1) parallel a metal total head balance pipe (4) and static pressure balance pipe (6) respectively be installed, one end of two tubes blocks, the other end is uncovered, on the surperficial same axis of ram-air pipe balance pipe (4), positive center position at airflow direction C, offer several total head gaging holes (4-1), total head gaging hole (4-1) is to open a circular groove on metal tube, aperture in groove centre drill one access tube forms, and on static pressure balance pipe (6) surface, on the single file axis of airflow direction C symmetry windward side direction in an angle, offer somely to the aperture that communicates in the static pressure balance pipe (6), be static opening (6-1).

Owing to adopted such scheme, need not working medium is carried out throttling, can design measuring point quantity according to actual needs, the realization gridding method is measured, sensor measurement precision height, flow coefficient k is stable, and pressure sensing hole is difficult for stopping up, system architecture is simple in addition, cost is low, be easy to installation and maintenance, is highly suitable for on-line automaticization of the air quantity monitoring in large and medium-sized air channel.

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

Figure-1 is a structural representation of the present utility model;

Figure-2 is that the utility model A-A is to figure;

Among the figure, 1. inner flange 2. outside flanges 3. fixture splices 4. total head balance pipe 4-1. total head gaging holes 5. location-plate 5-1. pilot holes 6. static pressure balance pipe 6-1. static opening C. wind directions

In the drawings, outside flange (2) is integrally welded with the air channel, total head balance pipe (4) and static pressure balance pipe (6) are securely fixed in the air channel, the pressure that total head gaging hole (4-1) records is the pressure after the effect of streaming that produces along pipe surface, because total head gaging hole (4-1) has adopted groove structure, can destroy the effect of streaming, reduce because of streaming the error of generation, thereby guaranteed measuring accuracy.Static opening (6-1) is and the symmetrical at an angle a pair of aperture of offering of airflow direction C, because air-flow does to stream motion around pipe, even airflow direction C and static opening (6-1) angle generation deviation, because a static opening (6-1) institute measuring pressure changes to the pressure augment direction, another reduces direction to pressure and changes, both in static pressure balance pipe (6) average after, still can keep measured value more accurately.The effect of total head balance pipe (4) and static pressure balance pipe (6) is after on the one hand that each gaging hole is measured pressure signal mixes, obtain mean pressure, also play the transfer function of pressure signal on the other hand, the difference of pressure signal is average dynamic pressure value, measures on the section at one, measures with many sensors, promptly realized the gridding method measurement, the precision height, flow coefficient k is a linear relationship with the working medium flow of surveying, and can realize the on-line monitoring of air quantity, because gaging hole is located at windward side, there is not vortes interference, so be difficult for stopping up long-term the use, dependable performance, its structure is also simple, and cost is very low, is easy to installation and maintenance.There is a pilot hole (5-1) at location-plate (5) center, after in the air channel guide rail being fixed, guide rail is penetrated pilot hole, just this sensor can be installed and fixed smoothly, and can guarantee setting angle comparatively accurately.

Claims

1, a kind of standard air measuring sensor, form by balance pipe and probe, it is characterized in that: inner flange (1) is connected with outside flange (2) by bolt, on inner flange (1) face, perpendicular to inner flange (1) a metal total head balance pipe (4) and a static pressure balance pipe (6) are installed abreast by fixture splice (3), one end of two tubes blocks, the other end is uncovered, on the surperficial same axis of ram-air pipe balance pipe (4), positive center position at airflow direction C, offer several total head gaging holes (4-1), total head gaging hole (4-1) is to open a circular groove on metal tube, aperture in groove centre drill one access tube, and on static pressure balance pipe (6) surface and air flow direction C, become on two parallel axis of windward side of identical angle, offer some apertures, be static opening (6-1) communicating with static pressure balance pipe (6).

2, canonical measure sensor according to claim 1 is characterized in that: the direct and air channel welding of the outer rim of outside flange (2).

3, canonical measure sensor according to claim 1 is characterized in that: in the centre of location-plate (5) pilot hole (5-1) is arranged.