Research Of Internal Mixer's Hydraulic Control System Based On CANbus

With the vigorous development of rubber industry, the rubber equipments are also encountering a good opportunity now. The rubber equipment is the essential equipment during the process of tire production and kinds of rubber products production, and it's capability decide the manufacture quality of the first working procedure of rubber production - rubber refine procedure. The internal mixer is one of the main rubber equipments which have been used by most rubber production factory, and a hydraulic control system based on CANbus is proposed in view of the insufficiency of exiting hydraulic control system.The hydraulic system of the internal mixer is divided into three parts after analyzing it densely, they are the control part of up spigot, the control part of down spigot and pin, and the control part of feeding gate. In this article three controller nodes used to control each of the three part are designed seperataly, and the intelligent sensor nodes are designed to realize the close-loop pressure control with the up spigot node.The output pressure control of the up spigost is one of the key factors impacting the quality of rubber production, so the up spigost pressure controller is the key part of the system. As it is rich in function resources and its anti-interference ability is strong, the 16bit MCU MC9S12DP256 which is the product of Freescale company has been adopted as key calculate unit of the controller. The techniques of separated power, photo isolate for input/output and shielded crust have been taken to make the system more strong in reliabilities; As to the structure of software, the integration of super loop and time-slip system have been used, this kind of structure can make the system work as a real time system and can be designed simply. A new kind of Fuzzy_PID control method has been put out, and it works well in practice. The intelligent sensor nodes can display the value of pressure by the LED, and can realize non-linear compensation through multi-point calibration. The PC software are programmed with Visual Basic langue, it can set parameter for nodes and draw the curve of controlling results.