大扭矩直驱式超精密液体静压转台热态特性控制与优化

The thermal characteristics control and optimization of a large torque directdrive ultra-precision hydrostatic rotary table

直驱式液体静压回转工作台在有限的空间内集中了电机发热、轴承摩擦等多个发热源,其热态特性控制与优化显得极为重要。对某大功率超精密液体静压回转工作台从加强散热、减少热源强度和结构优化3个方面开展了其热态特性控制策略研究,得益于稀油大流量静压支承、止推上置电机下置、电机强冷等技术措施,热态特性分析及测试表明,转台系统工作端具有较低的温升与较小的热伸长,且由温升与热变形引起的静压油粘度变化及油膜间隙变化对转台系统承载性能影响较小,研制的转台系统具有良好的热态特性。

The direct drive hydrostatic rotary table concentrates many heat sources such as from motor heating,bearing friction and so on in limited space.As a result its strategy of thermal characteristics control and optimization seems particularly important.For a high-power and ultra-precision hydrostatic rotary table,the control strategy of itsthermal characteristics is studied from three aspects,including strengthening heat dissipation,reducing heat source intensity and structural optimization.Thanks to some technical measures such as hydrostatic support from large flow of thin oil,thrust upper and motor lower and forced cooling of motor,the thermal characteristics analysis and test indicate that the working end of the rotary table haslower temperature rise and smallerthermal elongation.Moreover the variations from hydrostatics-oil viscosity and oil-film gap caused by temperature rise and thermal deformation have little effect on the loading performance of the rotary table system.As a result the developed rotary system has excellent thermal characteristics.