Adjustable clamping force control system based on PLC

CUI Yuqing, JIANG Zhaoliang, YI Wei

(Key Laboratory of Highefficiency and Clean Mechanical Manufacture, Shandong University, Jinan 250061, China)

Abstract: In order to solve the problems of deformation control of thin part milling with optimal clamping force, a hydraulic fixture with adjustable clamping force online(HFAC) was designed based on PLC technology. The HFAC system was composed of clamping mechanism, hydraulic system and control mechanism. The realtime closedloop control of PLC was used to adjust the outlet pressure of the electrohydraulic proportional pressure reducing valve, the highprecision clamping force was obtained and the automatic control function of pressure on line was realized. The test results show that, the HFAC system can realtime adjust the clamping force under the machining requirements, and the control precision of clamping force is about 3%,namely it has good stability and higher control precision of clamping force.

Key words: hydraulic fixture with adjustable clamping force online(HFAC); deformation control; PLC