Design of adaptive special fixture for bridge arm parts

YE Jun
（ School of Intelligent Manufacturing, Zhejiang Institute of Mechanical
& Electrical Engineering, Hangzhou 310053, China）

Abstract: Aiming at the problems that bridge arm was a special-shaped casting, it took a lot of time to adjust the clamping, which resulted in low machining efficiency, high labor intensity and low qualified rate of finished products, the mechanical structure of the fixture was designed through the analysis of the drawings and processing technology of the bridge arm parts. The hydraulic control system of the fixture was planned and designed by using the characteristics of the hydraulic fixture, which was stable and easy to operate. To reduce the labor intensity and realize the intelligent production demand, the fixture was controlled by the PMC program of the numerical control machine tool through the control address distribution of signal, PMC programming and so on. to achieve the purpose of intelligent production. The results show that the fixture has a significant effect on production efficiency and processing quality，it can achieve fast and accurate clamping positioning, its clamping efficiency is increased by 3 times, and the product processing quality is stable.

Key words: adaptive; special fixture; hydraulic control; production material control (PMC)