A tensioning and deviation correcting system for the steel belt of a plastic film casting unit

Abstract

The invention provides a tensioning and rectifying system of a steel belt of a plastic film casting machine set. The system comprises the steel belt, a driving roller, a tensioning cold roller, a base, a hydraulic system and a PLC system, wherein the hydraulic system comprises a left hydraulic cylinder, a right hydraulic cylinder, pressure sensors, displacement sensors and hydraulic stations; the PLC system comprises a plurality of PID rings and AO modules; pistons of the left hydraulic cylinder and the right hydraulic cylinder are controlled to move through PID operation, and two shaft ends of the tensioning cold rollers are accordingly driven to move, so as to achieve the rectifying and tensioning of the steel belt; a side edge detecting sensor is arranged at the edge of one side of the steel belt and used for detecting the offset of the steel belt in real time; extreme position proximity switches are arranged at two sides of the steel belt and used for protecting the steel belt. The system is provided with a manual control mode for directly setting output pressure value for the left hydraulic cylinder and the right hydraulic cylinder. With the adoption of the system, the offset of the steel belt in running can be effectively kept within a fixed range, and meanwhile, the tensioning force of the steel belt is constant, and as a result, the consistency of the steel belt in running and the quality of thick cast sheets can be obviously improved.

Description

technical field [0001] The invention relates to the technical field of a plastic film casting machine, in particular to a steel belt tensioning and deviation correction system of a plastic film casting unit, which performs real-time deviation correction on the deviation generated and accumulated during the operation of the steel belt, and keeps the steel belt state of tension. Background technique [0002] Tape casting is one of the main molding processes of plastic film slabs. It is mainly formed by high-temperature plastic resin solution being molded by a die, then cast and attached to a flat steel belt, and the slab is cooled and formed as the steel belt travels. The consistency and stability of the steel belt running determines the quality of cast film slabs, so a sophisticated steel belt detection and deviation correction system is required to ensure it. In recent years, there have been some patent applications for steel belt detection and deviation correction systems. ...

AI Technical Summary

Problems solved by technology

This system implements two closed-loop control systems for the steel belt deviation correction of the driving wheel and the driven wheel, and is equipped with idler rollers and pressure rollers. The system is more complicated, there are more detection sensors, and the cost is expensive. It is more suitable for long-distance conveying of steel belts.

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