SPINDLE ATTACHMENT DEVICE OF MACHINE TOOL

摘要

A spindle attachment device used by fitting to the tip of the spindle of a machine tool. The spindle attachment device (11) comprises a hollow casing (13) having an internal space, an input shaft (17) rotatably supported inside the casing, an output shaft (19) rotatably supported inside the casing, a coupling member (15) connected to the input shaft and joining the input shaft to the spindle of the machine tool, a gear train (21) disposed between the input shaft and the output shaft and transmitting the rotational speed of the input shaft to the output shaft after increasing the rotational speed, and tap holders (25) and (27) for mounting a tap tool on the output shaft. The spindle attachment device can transmit the rotational speed of the spindle to the tap tool after increasing the rotational speed to tap a work at high speeds while suppressing the rotational speed of the spindle.