RU1768985C - Flow meter for loose ferromagnetic material - Google Patents

Abstract

Usage: measuring the flow of ferroparticles in a gas or liquid stream. SUMMARY OF THE INVENTION: A flow through a pipeline affects the inductive coupling of transformer windings between which a ferromagnetic shield is mounted. The differential signal of the secondary windings of the transformers is proportional to the flow rate of particles. 1 ill.

Description

The invention relates to a device for measuring the flow rate of bulk ferromagnetic material and can be applied in various industries where flow rate measurement of bulk ferromagnetic materials is carried out, for example, in shot blasting systems of sewage foundry machines for determining the flow rate of shots supplied to shot blasting machines.

A device is known for measuring the flow rate of bulk materials when they fall freely in a vertical pipe by receiving an inductive sensor signal mounted on the pipe, and then converting this signal.

The closest in technical essence and the achieved result to the proposed is a device in which the flow rate of bulk ferromagnetic material is measured using a measuring transformer mounted on a vertical pipe in which the material flows. Signal at the output of the measuring transformer in the measuring circuit

corresponds to the concentration of the material and, therefore, its consumption.

The disadvantage of this device is the low measurement accuracy due to the large zero drift of the measuring device caused by the instability of the magnitude, voltage frequency and ambient temperature.

The aim of the invention is to improve the accuracy of measuring the flow rate of bulk ferromagnetic material by reducing the zero drift of the measuring device.

The goal is achieved in that a device for measuring the flow rate of bulk ferromagnetic material, containing a pipeline of non-magnetic material and a first measuring transformer mounted on it, is equipped with a second measuring transformer mounted coaxially to the first and a ferromagnetic screen located between them, while the primary windings of the transformers are connected between each other in series, according to, and the secondary windings are connected in series and counter-installed

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symmetrically with respect to the ferromagnetic screen and the corresponding primary windings.

In FIG. 1 is a diagram of an apparatus for measuring the flow rate of bulk ferromagnetic material: FIG. 2 is a construction of a device.

The device for measuring the flow rate of bulk ferromagnetic material contains a pipe 1 of non-magnetic material, two electric coils 2 and 3 are wound from the outside of the pipe 1, the first measuring transformer. Behind these coils, a ferromagnetic screen 4 is installed with a cut along the generatrix. On the. a ferromagnetic screen 4 is wound two more electric coils 5 and 6 - the second measuring transformer, which is installed coaxially with the first measuring transformer. The primary windings 2 and 6 of the first and second measuring transformers are interconnected in series - in accordance with and connected to the supply voltage of the alternating current. The secondary windings 3 and 5 of the first and second measuring transformers are interconnected in series, installed symmetrically to the ferromagnetic screen 4 and connected to the measuring device 7 (for example, an ammeter).

The device operates as follows. The primary current flows through the primary windings 2 and 6 of the first and second measuring transformers, creating an alternating magnetic field around the windings. The magnetic field of the primary winding 2 of the first measuring transformer induces an emf in the secondary winding 3 of the same transformer, the magnitude of which depends on the magnitude of the supply voltage, its frequency, ambient temperature, and also on the amount of ferromagnetic material in the pipeline 1. Than the more ferromagnetic material in the pipeline 1, the greater the magnetic flux induced by the current of the primary winding 2 of the first measuring transformer, and the greater the emf in the secondary winding 3 of the same transformer. The magnetic field of the primary winding 6 of the second measuring transformer induces in the secondary winding 5

of the same EMF transformer, the value of which depends on the number of turns of the secondary winding 5, the current in the primary winding 6, on the magnetic permeability of the ferromagnetic screen 4, and on the amount of material in

it does not depend on the pipeline, since the windings of the second measuring transformer are protected from the pipeline containing ferromagnetic material by the screen 4. The measuring device 7 registers a difference signal in the circuit of the secondary coils 3 and 5 of the measuring transformers. The difference signal of these coils depends only on the amount of bulk ferromagnetic material in the pipe 1.

Claims (1)

SUMMARY OF THE INVENTION A device for measuring the flow rate of bulk ferromagnetic material, comprising a non-magnetic conduit material and a first measuring transformer mounted on it, characterized in that, in order to improve accuracy, it is equipped with a second measuring transformer installed coaxially with the first and ferromagnetic shields located between them, while the primary windings of the transformers are interconnected in series according to, and the secondary windings are connected sequentially opposite and installed symmetrically with respect to the ferromagnetic screen and the corresponding primary windings.  Utftsm 1 figure 1