SCREW GRINDER Russian patent published in 2007 - IPC B23G1/38 

FIELD: finish abrasive working of helical surfaces of precise screws.

SUBSTANCE: grinder includes diamond-abrasive tool in the form of wheel mounted in mandrel and rest. Diamond-abrasive tool is in the form of three wheels mounted in housing, simultaneously taking part in working process and serving as rest. Said three wheels are arranged in cross plane and they are equally spaced one from other in axial direction by distance equal to 1/3 of pitch of worked screw. Rotation axes of mandrel with wheels are inclined relative to blank axis by angle equal to lead angle of screw surface turns. Said wheels have individual drive units and they are mounted with possibility of self-aligning and providing the same radial feed by means of helix-rack mechanism. The last includes three rack cleats arranged in radial grooves of housing and supporting wheels with drive unit and central helical disc engaged with said cleats and with small cone gear. Housing has central opening for placing blank.

EFFECT: enhanced quality and efficiency of working.

3 dwg