New Autmatic Thread Rolling Machine using the Rolling Dies of Eccentric Roller Type

Abstract

Results of experimental studies on a new-deviced thread rolling machine using a pair of rolling dies of eccentric roller type are described. (1) By a new thread rolling machine, the rolling dies were fixed slghtly eccentric on each axis of rolling dies, which was fixed at any desired distance during the rolling operation. (2) The outside of the rolling dies is circular form and not relived, so the accuracy and the durability of rolling dies are satisfactory compared with those of the thread rolling machine of hydraulic type. (3) The construction and the operation of the new thread rolling machine are very simple and so the full automatic operation could be realized very easily. (4) During the operation, the rolling pressure changes very gradually and the rolling forces are not unbalanced, so the rolling action is very smooth and not causes any accident. (5) Diameters of threads which can be rolled by this type of machine range from 2 mm to 16 mm and up to the length of 60 mm. (6) The work pieces were fed automatically to the rolling dies and the thread rolling could be completed in a few seconds, the work piece being made 5∼12 revolutions by thread rolling according to the diameter. (7) The accuracy of the rolled threads is so high as the grade JIS 1 st class. (8) By this machine, the threading action must be completed during about half revolution of the rolling dies, so the diameter of the rolling dies is comparatively large, say 140∼160 mm.