Electronic control method for transferring heavy to lower level in power-off period of quenching crane

Abstract

The invention relates to an electronic control method for transferring heavy to a lower level in a power-off period of a quenching crane and relates to an electronic control system for a quenching crane. The invention solves the problem of quickly putting a large-size workpiece into solution by using a crane when the power grid is power-off. The method of the invention is performed by an electronic control system which comprises an AC voltage and speed regulating device, a motor, a DC voltage and speed regulating device, a charger, a logic control device, a storage battery, a lifting resistorand a brake. When the quenching crane ascends, the AC voltage and speed regulating device controls the motor to work; when the quenching crane descends, the DC voltage and speed regulating device controls the motor to work; when the power grid is power-on, the logic control device controls the charger to charge the storage battery; when the power grid is power-off, the logic control device controls the motor to run and open the brake; and the descending potential energy is consumed by the lifting resistor.

Description

technical field [0001] The invention belongs to the electrical control system of hoisting machinery, and in particular relates to an electrical control method of a quenching crane that can safely lower heavy objects when the power grid is cut off. Background technique [0002] The quenching crane is a special crane in the heat treatment process. It has a rapid lowering mechanism to ensure that the workpiece to be quenched is immersed in the solution quickly and at the same time. When quenching in an oil bath, the workpiece will catch fire when it comes into contact with the solution, and the fire will extinguish when immersed in the solution. Therefore, it is required to put the workpiece into the solution at the fastest speed. Even a power outage requires that the workpiece be brought into solution quickly. [0003] The current practice is: [0004] 1. When the crane is in the quenching operation, the power grid suddenly fails, and the support brake is opened manually, p...

AI Technical Summary

Problems solved by technology

This method of lowering workpieces is slow and dangerous, especially for large workpieces and long rod workpieces, it takes a long time, so fire protection measures are often required when large workpieces are quenched

[0005] 2. Since the potential energy is completely consumed by the wear and tear of the brake shoe and the brake wheel on the brake, the wear of the brake shoe and the brake wheel of the brake is relatively serious

[0006] 3. Because the time for lowering the workpiece is long and discontinuous, it is difficult to guarantee the quenching quality of the workpiece, and the workpiece may be scrapped

Images