Multi-objective topology optimization for cooling element of precision gear grinding machine tool

Abstract

The machining accuracy of the gear grinding machine tool is significantly reduced by the thermal error, and then an effective control of thermal error is imperative. To control the thermal error, an innovative idea for directly cooling a moving heat source for the gear grinding machine tool is proposed to replace the substitute hollow screw cooling method, and a multi-objective topology optimization approach is proposed to design the cooling element for precision gear grinding machine tool. The results show that the heat transfer capability of the topology optimization-shaped channel is much more outstanding than that of the traditional serpentine-shaped cooling channel, and the pressure drop is reduced by 2–3 times compared with that of the traditional serpentine-shaped cooling channel. The cooling element is embedded into the precision gear grinding machine tool, leading that the temperature rise of the moving nut is reduced by more than 3 K in and that the thermal elongation of the screw shaft is reduced by 10 %. The improvement rate for the repetitive positioning accuracy is in the range of [29.03 %, 92.59 %] and the grinding accuracy is improved by approximately 65 % by using the designed cooling element with topology optimization-shaped channel.