THREAD CUTTING APPARATUS USING THREADING DIES AND SCREW TAPS FOR LATHE Russian patent published in 2006 - IPC B23G1/44 

FIELD: working, thread cutting and sizing preliminarily threaded large-size threads.

SUBSTANCE: apparatus includes mandrel with cone stem; tool holder supporting flanged casing mounted in mandrel with possibility of axial motion; yoke and bracket engaged with yoke. In order to enhance thread quality and efficiency of threading process, yoke is provided with groove having convex surfaces engaged with bracket made in the form of guide secured to end of cross slide of lathe rest at side opposite relative to tool holder. Ring having sector-shaped end recesses with single-side undercut with inclined surface is rigidly mounted in flange of casing. End of tool holder is provided with sector-shaped protrusions engaged with sector-shaped recesses. Said protrusions have lateral lug with inclined surface engaged with undercut and tapered portion opposite to lateral lug and they are designed for engaging with locking member in the form of screw chamfered by 45° in its end. Angular size of sector-shaped protrusions of tool holder is less than size of sector-shaped recess of ring.

EFFECT: enhanced quality of thread, improved efficiency of thread cutting process.

6 dwg