| 摘要 |
PURPOSE:To facilitate mount/dismount of work thus to improve the machining efficiency in a vacuum chucking device for adsorbing and holding a thin board by supporting a work holder floatably against the rotary drive shaft and enabling usage of vacuum chuck. CONSTITUTION:Upon lifting of ram 9 in a vacuum chucking device, the vacuum chucking body 14 will move relatively with the drive shaft 20 and lower and the holding body 15 will contact against a drive pin 16 to be suspended. Under this state, work W is adsorbed to the vacuum adsorbing face 17 of vacuum chucking body 14 to lower the ram 9 while the spindle 11 is rotated to rotate the vacuum chucking body 14 constituting a work holder 10 through a drive shaft 20, drive pin 21 and an engaging groove 22. Lowering of ram 9 will stop after contacting of work W against the lapping machine 3 and lowering by predetermined distance. Consequently, suspension of holding body 15 is released to contact the work W against the lapping machine 3 and perform machining. Here, the magnetic field 28 will move axially together with a magnet 29 to seal the gap 27 continuously thus to maintain the vacuum chamber 26 air-tight. |
