The invention relates to a tool holding device comprising a tool holding body for securing, in a fixed manner, a rotary tool comprising a shaft, provided with a clamping section and a receiving opening for the shall of the tool, a coolant feeding device for pressurized fluid, at least one coolant guiding device for guiding the coolant into a clamped tool shaft. The coolant guiding device is designed as at least one flat groove on an inner side of the receiving opening, joining to the front side on a free end of the tool holding body and directly adjacent to the tool shaft in the surroundings of the tool holding device or a coolant storing chamber and or collecting chamber is provided in the region of the free end of the tool holding body, to which the at least one coolant guiding device joins. The coolant storing chamber and or collecting chamber is connected by means of an annular gap to the surroundings of the tool holder device. The coolant storing chamber and/or collecting chamber and the annular gap are defined at least partially by the work shaft.

In a precision machine tool wherein a spindle head 20 that is movable in the up and down direction is disposed on a column 14 disposed on a bed 10 and a water storage space for storing temperature-regulated cooling water is formed inside the column 14, the column 14 has, in a lower part thereof, intake ports 38a and 38b through which cooling water is led into the water storage space, the column 14 has, in an upper part thereof, a drain opening 40 through which a cooling water is led outside, and an air vent hole 49 through which air in the column is discharged is formed at a position higher than the drain opening 40.

In a machine tool spindle device, a draw bar is arranged inside a center hole of a spindle, and a disc spring is arranged inside a spring member arrangement space between the draw bar and the center hole. A draw bar inner pipe is inserted inside a through hole of the draw bar, and the interior of the draw bar inner pipe is used as a coolant passage. A gap between the draw bar inner pipe and the through hole is used as an air passage for supplying the purge air, and the interior of the spring member arrangement space is used as a coolant supply passage for supplying coolant to cooling jackets of the spindle.

The present invention provides, in one aspect, a router including a motor unit and a base configured to selectively receive the motor unit to support the router on a work piece surface. The motor unit includes a motor and a spindle configured to output a torque supplied by the motor. The base includes an input shaft configured to selectively couple to the spindle, an output shaft laterally offset from the input shaft, and a belt. The input shaft includes a first pulley and the output shaft includes a second pulley and a tool holder. The belt wraps around the first and second pulleys to rotationally couple the input shaft to the output shaft. When the motor unit is received into the base, the spindle couples to the input shaft.

A router includes a motor unit and a base configured to selectively receive the motor unit to support the router on a work piece surface. The motor unit includes a motor and a spindle configured to output a torque supplied by the motor. The base includes an output shaft laterally offset from the spindle when the motor unit is received into the base, the output shaft including a tool holder. The base also includes a fan configured to generate airflow within the base.