SU690300A1 - Float-type rate-of-flow transducer - Google Patents

Description

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The invention relates to the field of measurement technology and can be used to measure the flow of liquids in open channels with an arbitrary shape of a fixed channel profile.

There are flowmeters in which the heat transducer speed is installed in the float, and the transducer level is located on the gauge mosquito.

Such flow meters do not take into account the change in the channel cross section of a different profile depending on the fluid level of the fluid.

Flowmeters are also known that contain a heat transducer located in a float made in the form of thermosensitive elements, one of which is equipped with a heater, and a level transducer pivotally connected by a lever with a float and made in the form of an annular chamber half filled with non-evaporating liquid with the thermistors placed profiled, taking into account the channel profile, inside it.

The known device is not sufficiently reliable and has a complex structure.

The purpose of the invention is to improve the accuracy and reliability of the device and simplify its construction.

This is achieved by the fact that in the proposed consumption of flow the level converter is made in the form of a diamagnetic material located in the PSD, on the side surface of which are grooves, one is circular, the second is profiled, in the first groove is an excitation winding, in the second there is a measuring winding The cylinder with windings is covered by a U-shaped magnetic core, and the measuring winding is included in the diagonal of the power supply of the bridge measuring circuit.

FIG. 1 - General view of the flow meter described; in fig. 2 is a structural diagram of an angular displacement sensor; in fig. 3 - the process of converting an izmenane level to an alternating current voltage; in fig. 4, a — is dependent (x; th changes in area gi; fopos with a trapezoidal section of a fixed channel with a change in level; FIG. 4, b shows the nature of the change in output voltage and the character of the profiling of the measuring winding; FIG. 5 shows the measuring diagram of the flow meter The flow meter contains (fig. 1) a flow ring of a cylindrical float 1, hinged by means of a lever 2 on a metalwork of a hydrometric bridge 3. Inside the float body in the bottom part are fixed semiconductor thermal protection 4 and 5, and packed with a heater 6, and on the axis 7 a movable magnetic circuit 8 of the inductive level converter 9 is fixed. The inductor 1 of the first level converter (Fig. 2) comprises a housing 10 of insulating material (PA) of the material, in which parallels the circular excitation winding 11 and the planar (} The measuring measuring winding 12 has a profile that corresponds to the profiled channel; the windings are covered by long rods of the U-shaped magnetic core 8. The flow meter operates as follows. The flow rate is measured by a heat transducer, in which heat-sensitive lines 4 and 5 are installed inside the case of non-contact with a measurable medium, heat-sensitive lines 4 and 5 are installed before and after the heater along the flow. With a lime temperature difference intended by thermal sensors and the power released in the heater, the heat transfer coefficient, which is mainly dependent on the flow rate, is determined. Moving the float and changing the angle of the lever frame when changing the flow level, the magnetic conductor moves relative to the flat measuring winding. The process of converting the change from urszn to ac voltage is illustrated in fig. 3. To clarify the principle of transformation, cut the transducer along the generator cylinder parallel to the leads of the excitation windings on the measuring winding and turn the cylinder. The angular displacement of the magnetic core 8 transmitted through the axis 7 when the liquid level (float position) changes in FIG. 3 is shown as a linear movement (along the arrows) up and down along the axis of the drawing. Thus, by the principle of operation, this converter refers to converters with a variable air gap area, i.e. with a low level of snubber, the magnetic core is at the bottom and under the influence of the magnetic circuit there is an area ABC. With an increase in the level of water flow in the channel, the magnetic core goes up and under the influence of the magnetic flux there is already an area D W N, i.e. much larger, which leads to an increase in EMF at the terminals of the measuring winding. The static characteristic of this converter is straightforward, subject to the law y ax + i. The slope of the line depends on the excitation current, the number of turns of the measuring winding, as well as the angle of inclination L of the measuring winding component. Such a transducer (the level operator is applicable for gypsum towers with CRs with a fixed floor and a fixed channel. The area of a g / fopost with a trapezoidal fixed channel varies according to the law (B 4-2 mH) H, i.e. it is a dependency shown in Fig. 4a where B is the channel width along the bottom; W is the bank slope coefficient; / - | is the current value of the water flow level in the channel. Thus, to observe the Q "WBWV dependence, where V is the flow rate; K is a constant g drop rate , the output value of the level converter should always give a linear dependence on pr For this triangular winding of the converter should be profiled, as shown in Fig. 46. In the measuring circuit of the flow meter (Fig. 5), the bridge output, proportional to the flow rate V, is multiplied by the bridge supply voltage proportional to the flux level H.e., calculation of the channel water flow according to the known Q-BHV Q. The variation of the channel width, depending on the level B-H (2 C1 + B), is automatically taken into account by the winding measurement profile. By varying the current in the winding, the excitation of the inductive level converter, the heating power and the resistance value in the arms of the speed measuring sensor during balancing of the flow meter, the flow meter is calibrated with respect to this hydropost. The scope of the invention. A float converter, a flow rate of a heat transducer with a height, made in the form of semiconductor temperature-sensitive elements, one of which is equipped with a heater located in the float, pivotally connected with a hydrometric MOSTIKOM level converter and a bridge measuring circuit, which includes a heat sink. 9 by the fact that, in order to improve the accuracy of the device and the reliability of the device operation and simplify its design, transform the level of the device n in the form of a cylinder of diamagnetic material located in the float, on the side surface of which are filled with pairs, one is circular, the second is profiled, the excitation winding is located in the first groove, the second is the measuring winding, The measuring winding is included in the diagonal power supply of the bridge measuring circuit. Sources of information taken into account in the course of actions 1. Author's testimony of the USSR J 285268, cl. G 01 F 1/68, 1969. 2. Author's certificate 512375, r. Q O1 F 1/68, 197-3.

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