| 摘要 |
PROBLEM TO BE SOLVED: To restrain vibration to decrease a change in position of center of gravity and also restrain vibration to decrease a guide gap in a spindle mechanism of a machine tool, particularly a clamp mechanism of a tool holder. SOLUTION: In a spring for sliding a draw bar to hold and release the tool holder, the guide mechanism of the draw bar to the spidle shaft is characterized to hold down the vibration during the rotation of the spindle. According to a first mode, a coil spring is used as the spring for sliding the draw bar, the removal machining for making the inside diameter of the coiled spring uniform is performed so that the gap between the outside diameter of the draw bar and the inside diameter of the coiled spring becomes minimum, and the coiled spring is guided integrally by the draw bar, whereby the shift of center of gravity of the spring caused by repetition of the spindle rotating operation and the tool clamp operation is decreased to reduce the amplitude of vibration. According to a second mode, the clamp mechanism includes a means for resiliently pressing a part of the draw bar to the radial direction of the inner wall of the spindle guiding the draw bar, and the draw bar is integrally held on the spindle to hold down the vibration level in all rotating speed ranges. COPYRIGHT: (C)2006,JPO&NCIPI |
