TOOL HOLDER CLAMP DEVICE FOR MAIN SPINDLE

摘要

PROBLEM TO BE SOLVED: To provide a screw fastening type tool holder clamp device coping to an automatic tool changer. SOLUTION: A tool holder shank part incorporated in a main spindle 1 and retractably fitted in a taper hole 9 formed in the tip part of a main spindle 1 is clamped through thread-coupling. In a so formed tool holder clamp device for a main spindle, the tool holder shank part is provided with a thread part 25 threadedly engaged with an axially formed thread hole. A clamp bolt member 23 to fix a tool holder through fastening of a shank part by a thread part 25 is rotatably and axially movably arranged in the central through-hole 19 of the main spindle 1 communicating with a taper hole 9. A drive shaft body 29 to rotationally drive the clamp bolt member 23 is rotatably and axially movably arranged in the central through-hole 19 of a main spindle 1, and engaged in a driving coupling state with a clamp bolt member 23 through an axial movement.