SU488986A1 - Electromagnetic flow meter - Google Patents

Description

: The invention relates to a measuring and information technology and can be used to control the flow of melts, electromagnetically conductive liquids in the metallurgical, chemical, mining industry. The known flow meters comprise a ribbed measuring channel, two flat field windings, an annular magnetic circuit and two electrodes installed along the diameter of the channel. The disadvantages of this flow meter are: design complexity due to the presence of flat windings, the presence of a transformer a. d. in the measuring circuit when the excitation windings are supplied with alternating current, which leads to significant measurement errors, the relative difficulty in operation is due to the inconvenient positioning of the electrodes. The purpose of the invention is to simplify the design and increase the measurement accuracy. To do this, in the proposed device, the magnetic circuit is located along the measuring channel, open at two intersections with the measuring channel, the magnetic poles are located across the measuring channel across its entire width, and in its gaps on the sides of the measuring channel are electrodes whose length is equal to the distance between the poles, on the other - lumped electrodes installed under the poles of the magnetic circuit, the conclusions of which are connected to the measuring circuit. FIG. 1 shows the proposed flow meter; in fig. 2 - the direction of the currents during the flow of fluid. The flow meter consists of an open O-shaped magnetic circuit 1 with an excitation winding 2. Moreover, the magnetic circuit is located along the plane of the measuring channel 3, the width of which is made up of the magnetic pole. A distributed electrode 4 is installed on one of the side walls of the channel under the poles of the magnetic core; its length is equal to the distance between the magnetic poles

toprovoda. On the opposite side wall of the channel 3 in the gaps of the magnetic core 1 there are two lumped electrodes 5, 6. The output signal is taken from these electrodes.

When a fluid flows in the layers of an electrically conductive fluid, under the poles of the mag ™ of the nitropipe 1, generating currents 1d and if, are formed. Directions of these currents

determined by the direction of flow f

and f at the intersection with the liquid, p

that is, under one pole the current I. is directed in one direction, under the other pole j - in the opposite direction.

Toki L and i thanks to the presence of race

The limited electrode 4 can be closed in one circuit according to, so that the measuring device connected to the electrodes 5 and 6 reacts to the total effect of the currents and I, which are proportional to the flow rate O, (fluid flow velocity).

Depending on the need to have an output signal in the form of direct or alternating currents, the field winding 2 is supplied with either direct or alternating current.

In the case of a flow meter on alternating current at the output of the transformer e. d.

at Q О, they are absent, since the current coupling, with the measuring circuit formed by the electrode 4s by the fluid layers and the connector by the 1 wires, is O, so

as in this circuit flows f and f

whether

sent counter.

Subject invention

An electromagnetic flowmeter containing an O-shaped open magnetic circuit with an excitation winding, in the gaps of which there is a measuring channel, electrodes and a measuring circuit, characterized in that, in order to increase the accuracy and simplify the design

the magnetic conductor is located along the measuring channel, is open at two intersections with the measuring channel, the poles of the magnetic conductor are located across the measuring channel across its entire width, and in its

the gaps on the sides of the measuring channel are electrodes, on one of the sides there is a distributed electrode, the length of which is equal to the distance between the poles, on the other - lumped electrodes,

installed under the poles of the magnetic circuit, the findings of which are connected to the measuring circuit.

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