To provide a spindle unit of a machine tool capable of automatically replacing tools and capable of machining a variable hole diameter such as cutting and horning a hole with a single machine.
The machine tool comprises: a spindle 13 capable of automatically replacing tools, freely turnably supported on a housing 11 and rotated by a spindle driving motor 19; a spindle-side draw bar 14 supported to be capable of going back and forth on a spindle hole 13a of the spindle 13; and a draw bar driving shaft 23 equipped on its outer peripheral surface with a thread 23a to be screwed with an inner peripheral surface of the housing, and freely turnably supporting a base end of the spindle-side draw bar 14 protruding from the spindle 13 via a bearing 22 in an integrally movable manner in the axial direction, and rotated by a draw bar driving motor 28. A leading edge of the draw bar 14 is coupled via a collet 30 with a base end of a tool-side draw bar 32 supported to be capable of going back and forth on an axial line of a tool 2 mounted on the spindle 13 to drive the draw bar 32.
| JP2869729 | [Title of Invention] Processing Machine |
| JP6385090 | Bearing device cooling structure |
| JPH10138013A | 1998-05-26 |
Tadahiro Mitsuishi
Yasuyuki Tanaka
Hiroshi Matsumoto