Mechanical pressure machine control method for slider stopping at certain point

Abstract

The invention relates to a method for controlling the compressor sliding block to stop at dead position. Wherein, it uses the rotation coder as the crank angle / block strike sensor of mechanical compressor, to feed collected angle information to the electric cam controller; the controller based on the crank angle information outputs cam signal, based on the passed angle in fixed time of crank to calculate out the crank speed. The invention is characterized in that: based on the brake angles of last two sliding blocks, it finds the incline factor of angle-speed curvature; when the compressor first operates in one sliding block speed, based on said factor, it can find the present brake angle; when the speed is stable, the brake angle will be automatically compensated referring to the shift from last brake angle; the brake angles in different speeds are stored; when the electric cam receives brake signal, based on preset speed to inquire database, and find out present brake angle; when block reaches said brake angle, outputting the brake signal.

Description

technical field [0001] The invention relates to a mechanical press, in particular to a method for controlling the top dead center position of a slider of a mechanical press, and belongs to the field of mechanical processing and computer automatic control. Background technique [0002] During mechanical press processing, the slider is generally required to stop at the top dead center position to ensure that there is enough energy to process the workpiece during stamping processing. In the past, the mechanical cam was used as the crankshaft angle detection device, and the logic control was realized by PLC. The disadvantage of this method is that it cannot be guaranteed to stop at the top dead center when the speed of the slider changes and the friction plate is worn. Every time the cam angle is adjusted, it needs to be manually adjusted, and a fixed angle is used as the braking angle. Moreover, the shortcoming of this method is that once the friction plates of the clutch work...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that it cannot be guaranteed to stop at the top dead center when the speed of the slider changes and the friction plate is worn. Every time the cam angle is adjusted, it needs to be manually adjusted, and a fixed angle is used as the braking angle.

Moreover, the disadvantage of this method is that once the friction plate of the clutch works for a long time, the braking performance will decrease; or when the speed changes or the air pressure changes, the slider cannot be guaranteed to stop at the top dead center.

Due to the need for manual adjustments, time is wasted, production efficiency is low, the number of actions of the clutch increases, and the service life is affected

However, there are strong nonlinearity and time lag between the braking angle of the clutch and the physical characteristics of the clutch itself, air pressure, flywheel speed and other factors, so it is difficult to establish an accurate mathematical model

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