TOOL UNIT

To provide a tool unit which can improve support rigidity of a rotary tool to a main spindle device.SOLUTION: A tool unit 100 comprises: a rotary tool 110 for processing a work-piece W; a first holder 120 which is so held as to be rotatable integrally with a main spindle 42, and is so connected to a first end part 110a of the rotary tool 110 as to be coaxial with the rotary tool 110 and to be rotatable integrally with the rotary tool 110; a second holder 130 which is so connected to a second end part 110b of the rotary tool 110 as to be coaxial with the rotary tool 110 and to be rotatable integrally with the rotary tool 110; and a third holder 140 which has a first support surface 144 which rotatably supports an outer peripheral surface of the first holder 120 at a first end part 110a side with respect to the rotary tool 110, and a second support surface 145 which rotatably supports an outer peripheral surface of the second holder 130 at a second end part 110b side with respect to the rotary tool 110, and is so connected to a main spindle housing 43 as to be relatively unrotatable.SELECTED DRAWING: Figure 5 【課題】主軸装置に対する回転工具の支持剛性を高めることができる工具ユニットを提供する。【解決手段】工作物Ｗを加工する回転工具１１０と、主軸４２に対して一体回転可能に保持されると共に、回転工具１１０の第一端部１１０ａに対し、回転工具１１０と同軸に、且つ、回転工具１１０と一体回転可能に連結される第一ホルダ１２０と、回転工具１１０の第二端部１１０ｂに対し、回転工具１１０と同軸に、且つ、回転工具１１０と一体回転可能に連結される第二ホルダ１３０と、回転工具１１０よりも第一端部１１０ａ側で第一ホルダ１２０の外周面を回転可能に支持する第一支持面１４４、及び、回転工具１１０よりも第二端部１１０ｂ側で第二ホルダ１３０の外周面を回転可能に支持する第二支持面１４５を有し、主軸ハウジング４３に対して相対回転不能に連結される第三ホルダ１４０とを備える工具ユニット１００。【選択図】図５