RU1804448C - Apparatus for protecting underground mine lifts from rope overlap - Google Patents

Abstract

SUMMARY OF THE INVENTION: a capacitor with a variable capacitance (1), a magneto-inductive sensor (2), an actuating relay (3), 1-2-3. 2 ill.

Description

.Five 1 The invention relates to mine hoisting installations and can be used in the coal and mining industries.

The purpose of the invention is to increase the reliability and safety of mine hoisting installations and to expand the scope of the apparatus.

In FIG. 1 shows a schematic electrical diagram of the proposed apparatus; in FIG. 2 is a vector diagram of the voltages and currents of forced oscillations in a series resonant circuit with voltage resonance.

The apparatus for protecting the hoisting installations from the cable inlet contains a magnetoelastic sensor 1 with an inductor Lg, a capacitor 2 with a capacitance C and an actuating relay 3.

The current strength in such a series resonant circuit is determined by the expression

U

I

(d-7) 2

wcy

where U is the voltage of the network;

o) Lg is the inductive resistance of the winding of the magnetoelastic sensor;

- - capacitance of the capacitor;

gk is the active resistance of the circuit circuit (only the resistance of relay winding 3 is conventionally accepted).

The protection device operates as follows.

If the lifting vessel hangs in the shaft of the shaft and the cable is subsequently let in, the force on the drive pulley and, consequently, on the magnetoelastic sensor decreases, as a result of which the magnetic permeability of its winding decreases, its inductance and inductance a) Lg become smaller, which becomes equal to the capacitance

1 - capacitor 2 (Fig. 2). It comes like that

U / C.

called voltage resonance, as a result of which the total resistance of the circuit becomes equal only to the active resistance of the relay coil gk, and in accordance with the formula, a fast

an increase in the current in the circuit, causing the actuating relay 3 to operate. The latter, by its opening contact, activates the braking device for the safety braking of the hoisting machine.

With the aim of expanding the scope of application of the Protection Device ... for lifting vessels with different own masses, a variable capacitor is used for tuning capacitors. If the shaft lifting installation is double-ended, a similar protection apparatus can also be applied to the second driving pulley. Thus, the safety of a mine lifting installation - is increased, and the use of sufficiently reliable and in a small number of elements of the protective apparatus as a whole increases the reliability of the lifting installations. In addition, the use of a capacitor of variable capacity makes it quite simple to adjust the apparatus for a mine lifting installation with any mass of the towing device, thereby expanding

the scope of the proposed apparatus ...

Claims (1)

SUMMARY OF THE INVENTION installations from the inlet of the rope, comprising a magnetoelastic sensor located under one of the bearings of the drive pulley, characterized in that, in order to increase reliability and safety in the work of mine hoisting installations, it is equipped with an executive relay and capacitors with a variable capacity, moreover, a capacitor with a variable capacity, a magnetoelastic sensor and an actuator the relays are connected in series and form a resonant circuit, while the executive relay. included in the safety brake of the mine hoist. Ui - JbJLg Figure 2