METHOD FOR ROTATIONAL CUTTING OF HELICAL GROOVES Russian patent published in 2006 - IPC B23B5/48 B23G1/00 

FIELD: metals turning processes.

SUBSTANCE: method comprises steps of mounting and fixing blank in fixture of lathe at shifting it relative to symmetry axis of spindle; imparting rotation to blank for determining predetermined pitch value of helical groove and necessary cutting speed; providing contact of cutter and blank in predetermined time intervals; selecting circle sector of blank by means of cutting edge of tool for one revolution of fixture; using fixture for mounting one or several blanks; securing support of fixture to housing of lathe. Said fixture includes central shaft having rigidly mounted in it front disc supporting front centers and their gear wheels and rear disc with rear centers; driven gear wheel and driving gear wheel joined with driven one through set of gear wheels. Driving gear wheel is rigidly secured to central shaft. Boss of driving gear wheel is clamped in chuck of lathe. In fixture with the aid of rear centers one or several blanks are mounted with possibility of rotation around their own axes in front centers. Rotation of one or several blanks that sets predetermined pitch value of helical groove is realized by transmitting rotation from spindle of lathe to driving pinion, then through set of gear wheels to driven gear wheel and through gear wheel or wheels of front center to one or several blanks. At cutting by means of cutter, blanks are driven to rotation around their own axes and simultaneously around axis of spindle. Sectors are formed on blanks for each next revolution of fixture at shifting by lead angle of helical groove. While repeating such cycles, helical groove with predetermined pitch is cut on blank due to selecting gear ratio of gear wheel or wheels of front disc and driving gear wheel of fixture and due to cutter feed.

EFFECT: enlarged manufacturing possibilities of lathe, lowered labor consumption at working parts.

7 cl, 2 dwg