COMBINED METHOD OF NEEDLE TURNING TREATMENT OF SCREWS Russian patent published in 2008 - IPC B23B5/36 

FIELD: metallurgy.

SUBSTANCE: method includes transfer of independent rotary movement to blank, at that this movement determines speed of cutting; while tool is subject to progressive motion conditioned by length feed. Blank movement is carried out against planetary axis set off against the central axis at a value of concentricity; and additionally planetary rotary movement is transferred to the blank against the central axis; this movement is kinematically tied with the length feed of the tool; at that per one turn of planetary rotary movement a support with the tool is transferred in lengthwise direction at a value of pitch of treated screw surface. The tool is made as tread cutter while cutting needle tool is installed diametrically opposite the latter and is equipped with a drive of independent crosswise feed identical to the drive of crosswise feed of the tread cutter; this cutting needle tool is designed for performing the function of a movable support holder, which is loaded with hold-down pressure to the blank; this pressure is equal to cutting force developed by the tread cutter.

EFFECT: expanded process facilities.

8 dwg, 1 ex