Research On Design Technologies Of Hobhead Part For Direct-drive Gear Hobbing Machine

The gear processing is developed an environment protecting, high-efficiency, high-precision and chipless machining mode, meanwhile the gear machine tools developed the completely-digital-control, function-complex, flexible, automatic, secure and network mode. Traditional gear hobbing machine can not satisfy performance demand of modern gear hobbing machine, because of its disadvantages, such as complex drive structure, low drive efficiency, low drive precision, bad abrasion, low cutting speed, and etc. normal NC gear hobbing machine has characteristics of CNC, good flexible and safety, but because the mechanical drive limit the cutting speed , it also can not fit for the demand of dry cutting.so ,some overseas companies have started to study zero-chain gear hobbing machine . zero-chain gear hobbing machine breaks through structure design principle of traditional gear cutting machine ,in which motorized spindle and built-in torque motor have been applied to realize rotary of hobbing cutter and workpiece-shaft.it is an important technological innovation of the design of gear machine tool. But the foreign Nought-Drive machine tools are expensive(2-3 times as much as the common digital-control machine tool), the design theory and the pertinent technical data are all kept absolutely secret that formed a situation of monopoly technology.In order to break the technology monopoly and improve the level of designing/manufacturing rapidly in our country's gear cutting machine, it's very necessary to study and develop high-speed and high-precision direct drive gear hobbing machine, one key of the research is the direct drive hobhead.This article makes a thorough study at the key technology of the hobhead's design, lays stress on analysing the four factors which can affect the of the spindle system, including the rotary-precision, the static-rigidity, the dynamic performance and the thermal deformation.The design of hobhead is based on the theory analysis. It consists of both B-axis and Y-axis power-parameter design, the encoder-selecting, the choice of the supporting and its configuration design, the bearing-rigidity calculating, the bearing lubricating and its preload design, the rotor and spindle'interference design, the stator cooling system design, the dynamic balance design of spindle system, Y-axis'pretensioning...