The Research Of Frequency Regulation Automatic Control System For Furniture Workshop's Pneumatic Conveying Equipments

The furniture workshops usually utilize pne umatic conveying equipments to improve hygiene and fire-proof condition, prevent environment pollution, enhance efficiency and at the same time achieve better working condition and product quality. However due to different techniques, equipment and management employed, there are also differences in power consuming in pneumatic conveying equipments. Some of them consume too much power, increase cost and undermine enterprises'competing ability. They some times even threaten the profits and survival of the enterprises. If frequency converter is added to the equipment, and rotational speed is requested according to production, energy will be saved and profits obtained. The article is aimed to achieve automatic regulation in accordance with the pressure changes. The system employs the closed loop. The pressures are picked by the pressure sensor and changed in analog input feedback signals. The signals are transferred into output signals. The output signals control the output of the frequency converter and regulate the rotational speed of the fans, and thus regulate the pressure of the main pipe. This paper gives detailed description of the main equipment and other accessory equipment. It also presents the blueprint of the control box in designing hardware. The article shows the process blueprint of the regulation, and then introduces the main functions of PLC and the design of the monitor interface. The system uses the relatively advanced "network engineering"techniques, i.e. industrial control computer and configuration software + PLC and program software + frequency converter + communication interface and agreement. It is the first time in pneumatic conveying equipments in the wood processing industry. The system will benefit the enterprises a lot and save much energy.