SU931637A1 - Method of controlling normal braking of mine hoist - Google Patents

Description

(5) METHOD OF MANAGING THE WORKING BRAKING OF THE MINE LIFTING MACHINE

one

This invention relates to a mine hoist, and more specifically to controlling the braking of a mine hoist machine.

When the operating brake is suddenly turned on by the operator, due to the application of the maximum braking torque value with the maximum speed of its rise, the lifting vessel may run onto the rope, which is dangerously large dynamic loads on the lifting machine components and the possibility of breaking the lifting vessel.

There is a known method for controlling the process of braking elevators and a device for carrying out this method, characterized by a three-stage range of variation of speed, and at the second stage of braking the value of the velocity of the elevator is constant. The method and the device allows to reduce the distance traveled at a slower speed.

However, this method does not allow to obtain the necessary dependence of the change in braking torque to ensure safe deceleration of the lifting vessel from the conditions of the rope running on it with unacceptable driver operating in the operating mode, as a result of which the maximum braking torque value can be applied with its maximum growth rate.

It is also known an explosion-proof electro-hydraulic device for controlling the working and safety drive of a brake for mine hoisting installations with one brake cylinder, which is made in combination of an explosion-proof electro-hydraulic pressure regulator for working braking and an explosion-proof electro-hydraulic amplifier for the safety braking of the space-controlled electro-hydraulic booster for the braking, separately for the braking electro-hydraulic pressure regulator for working brake braking one system by means of shunted spring valves, mounted x separately on drains from the electroregulator of pressure and from the electrohydraulic amplifier G2E. However, the known device, which implements one of the possible ways to control the braking of mine hoists, does not allow obtaining the braking torque characteristic, ensuring the safe operation of the operating brake. This is due to the fact that the braking torque value along the entire braking path increases and its stature value can be greater than allowed by the conditions of the hoisting vessel rushing onto the rope. If the braking torque rise rate is reduced so that the braking torque value does not exceed the allowable when the lifting vessel rushes onto the rope, the value of slowing down the lifting machine may be less than what is required and there is a danger of overshooting. There is a known method of controlling working torsion of a shaft lifting machine, according to which braking is performed in several steps by changing the braking torque in accordance with a predetermined J pattern. However, this method also does not allow to obtain the necessary dependence of the change in braking torque to ensure a safe deceleration from the conditions of the lifting vessel on the rope. The purpose of the invention is to improve the safety of the lifting machine. This goal is achieved by increasing the braking torque at the first stage to a value corresponding to the conditions for not lifting the vessel to the rope, at the second stage leaving it constant and equal to its maximum value at the first stage before stopping the lifting machine, and at the third stage without limiting the speed of its growth or to the maximum value corresponding to the locking of the lifting machine. FIG. 1 shows diagrams of the change in the speed of the braking torque; in fig. 2 is a block diagram of a control device for operating braking of mine hoists. At the first stage, the intensity of the increase in the braking moment is limited by the intensity control from the conditions of non-neglect of the lifting vessel to the rope. The value of the braking moment is increased from zero to the value M, the Intensity of the increase and the maximum value of the braking moment M in the first stage are determined for each particular lifting installation by calculation. The characteristic braking torque at this stage corresponds to section I of the curve. In the second stage, the magnitude of the braking moment is kept constant and equal to its maximum value M. in the first stage. The duration of the second stage is determined from the end of the period of growth of the braking moment in the first stage to the stopping of the lifting machine (section II of the curve). At the third stage, the intensity setting unit is turned off and the intensity of the growth of the braking torque is not limited to its maximum value (section III of the curve). In practice, the proposed method is implemented by applying a block diagram of a control device for operating braking. The braking torque setting voltage from the brake control unit 1 through the intensity setpoint 2 is supplied to the pressure regulator 3, which controls the drive of the operating brake k of the lifting machine 5. Information about the speed of movement and deceleration of the lifting machine 5 is selected by the speed sensor 6 and the delay sensor 7 kinematically connected with the winding unit of the hoist 5. This information serves as a control signal for intensity control 2. When the lifting machine 5 is stopped, the signal from the speed sensors 6 comes to the setpoint 2 of the intensity, which in this case does not affect the nature of the change and the magnitude of the voltage on the pressure regulator 3. When the car is moving, the speed sensor 6 turns on the intensity setting device 2, which limits the slew rate, the voltage value on the pressure regulator 3, and, accordingly, the braking torque so as to slow down the hoisting machine 5 no more than allowed by the lifting vessel to the rope . For each particular lift, the magnitude of this slowdown is determined by calculation. If the deceleration is outside the permissible limits, the deceleration sensor 7 corrects, via the intensity adjuster 2, the voltage of the brake torque setting applied to the pressure regulator 3. When the lifting machine stops, the speed sensor 6 sends a signal to shut off the intensity regulator 2 and the voltage from the braking commander 1 is fed to the pressure regulator 3 without a change, and as a result, Uero applies the maximum braking torque required for locking without speed limitation. increase. If at any stage the value of the braking torque does not exceed the limits allowed by the critical diagram, the braking torque limiting circuit does not interfere with the control of the hoist's operating brake drive. The implementation of the proposed method of controlling the working braking of mine hoisting machines contributes to an increase in the safety of operation of mine hoisting plants when working

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Claims (3)

Mf. braking from the conditions of non-neglect of the 1) removable vessel on the rope. Formula of inventive The method of controlling the working braking of a mine hoist, according to which braking is performed in several steps by changing the braking torque in accordance with a given program, characterized in that, in order to improve the safety of the hoist, in the first step the braking torque is increased to in accordance with the conditions of non-escape of the lifting vessel to the rope, at the second stage it is left constant and equal to its maximum value at the first stage until it stops at the lift machine, and at the third stage, increase it without limiting the speed of its rise to the maximum value corresponding to the locking of the lifting machine. Information sources, X taken into account during the examination 1.Patent of France N, cl. B 66 B 1/32, 1978. 2. USSR author's certificate number 17666, cl. B 66 D 5/30, TEB. 3. USSR author's certificate №, cl. B 66 B 1/32, 1976 (prototype). BUT/. 2