Wear Prediction Method of Differential Planetary Roller Screws Considering the Ambient Temperature Variations

Abstract

As a key component in fields such as high-precision machine tools, aerospace and weaponry, the thermal deformations in a differential planetary roller screw (DPRS) caused by the changes in ambient temperatures can lead to uneven load distribution and increased wear, which can seriously affect its transmission accuracy, efficiency, and service life. Therefore, the temperature rise of a DPRS at different ambient temperatures was studied using the block thermal network method, and the thermal deformations were calculated. A load distribution model of DPRS considering thermal deformation was developed, and a wear prediction method combined with surface roughness was proposed. The results show that the increase in ambient temperature has an obvious negative effect on the load distribution and wear depth of DPRS. Moreover, the DPRS temperature rise, load distribution and wear depth dramatically change with the variation of parameters such as load, speed and thread pitch. A DPRS durability test device that considers changes in ambient temperature was developed. Experiments with temperature rise and DPRS wear under different ambient temperatures were conducted to validate the theoretical analysis model.

Analytical Model of Tapered Thread Made by Turning from Different Machinability Workpieces

“…The technology of manufacturing helical and toothed surfaces requires an analytical approach to their shaping [36], the optimization of the technological route [37,38], the study of the latest approaches to stabilization of turning processes [39], and the development of special designs of cutting tools to ensure their shaping with minimal errors [40,41]. As presented by [42], the thread screw wear prediction method explains that reducing the ambient temperature is beneficial for enhancing the wear resistance of the screw. A thread milling motion control experiment realized with the help of a testbench validated that the method of PMSM driving developed in [43] significantly reduces contour errors compared with the usual methods.…”

“…After substituting the data X a = 22.16 mm, X d = 27.65 mm, X b = 27.93 mm, Z d = 3.17 mm, and Z b = 3.33 mm in Formulas (42) and (43), we obtain…”