Design and simulation of high precision feed drive for CNC turning machine

Abstract

Although the feed drives of modern machine tools are almost impeccable, especially in CNC machine they still have some unexpected errors so that the manufacturing accuracy is always limited abov~ μm. One of the most important reasons is errors of traditional joints, such as backlash in ball screws bearings. The resolution of feed drives is μm but it is affected by above errors, therefore the accuracy of feed drives is reduced and the precision of products is unreliability. All errors of traditional joint can be totally eliminated by using flexure hinges. The compliant mechanism using flexure hinges can transmit motion with high accuracy and does not contain any errors like backlash or wearing and thermal effects by friction forces. The paper presents a new design of high accuracy feed drive using compliant mechanism and piezo actuator. Some FEM and dynamic simulations are also executed to ensure the reliability of results.