Automatic locking device of lathe main shaft

The utility model discloses an automatic locking device of lathe main shaft, including friction locking device and hydraulic drive device, friction locking device on being fixed in the main shaft andcan along with its be rotary motion external friction taper sleeve and with coaxial setting of external friction taper sleeve and the inner friction taper sleeve that moves for its axial displaceable,inner friction taper sleeve and external friction taper sleeve have mutually support just can not the auto -lock circular cone type friction surface, the hydraulic drive device includes plunger rod,pneumatic cylinder and overlaps and be used for its return spring who resets that one side that the inner friction taper sleeve was kept away from to the pneumatic cylinder is equipped with the hydraulic fluid port on the plunger rod, the one end and the inner friction taper sleeve fixed connection of plunger rod, and the other end of plunger rod holds through its removal of hydraulic drive in thepneumatic cylinder. Difficu