To provide a machine tool, which is capable of preventing the air around a shaft coupling from diffusing to the entire region in a cavity, and which is capable of inhibiting the whole interior of a head from rising in temperature.
An angular ball bearing 2 is held in a bearing hole 13 through which a lower part of the head 1 having a cavity 12 passes. A lower end of a tool holding shaft 3 is fitted into and held by the angular ball bearing 2. An upper end 3f of the tool holding shaft 3 on the cavity 12 side is interlocked and coupled with an electric motor 4 via the shaft coupling 5. A regulation wall 19 for regulating an air flow occurring by rotation of the shaft coupling 5 is provided at a position facing the shaft coupling 5 inside the cavity 12, so that the regulation wall 19 can prevent the air around the shaft coupling 5 from diffusing to the entire region in the cavity 12.
HONDA AKIRA
TERASAKA NAOTO
Hideno Kono
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