A Study on Multi-functional Machine Tools for Agile Manufacturing

(1)高速、高刚度进给传动系统的研制研究开发了由20mm滚珠丝杠和转速为3000转/分、低惯量的伺服电机组成的进给传动系统，并对其性能进行了研究。结果表明，采用进给驱动系统可实现60 m/min的最高转速和1.0G的加速度，且伺服参数调优没有降低伺服刚度。然而，由于滚珠丝杠在高速运行时温度升高较大，因此必须研究热伸长的对策。(2)切削性能试验在(1)试验结果的基础上，研制了高导滚珠丝杠传动加工中心。利用加工中心对铝合金工件和铸铁工件进行了切削试验。这些工件用于客车发动机零件，是敏捷制造的主要目标。在面铣削和端铣削方面，加工中心的生产率比目前传输线上使用的常规切削提高了5-20倍。但在铸铁工件的钻削加工中，所用钻头的刀具寿命不足以满足高速切削的要求。

(1) Development of Feed drive system with high speed and high stiffnessthe feed drive systems have been studied and developed, which consist of ball screws with 20 mm in lead and sero motors with 3,000 rpm revolution and low inertia, and their performances have been investigated. It has been cleared that top speed 60 m/min and accelaration rate 1.0G were realized by the feed drive systems and the sero stiffness did not decrease by using sero parameter tuning. However we have to develop the counter measures for thermal elongation of ball screw due to fairly large temperature elevation under high speed running.(2) Cutting Performance testsThe machining center with high lead ball screw drive systems has been developed, based upon the results which were confirmed at (1). The cutting tests of alminum alloy workpieces and cast iron workpieces have been conducted by the machining center. These workpieces are used for passenger's engine parts, which are main target of agile manufacturing. At the face milling and end milling the productivities were 5-20 times improved by the machining center compare to conventional cutting used at the present transfer lines. But at the drilling of cast iron workpiece the tool lifes of used drills were not sufficiently long to high speed cutting.