A machine tool includes: a frame; a hollow ram disposed on the frame in a reciprocable manner; a hollow spindle to which a tool is mountable, rotatably supported by the ram, and having a lever hole penetrating the spindle in a radial direction and extending in an axial direction; a drawbar including a collet, reciprocate in the spindle, and urged toward a basal end of the spindle; a lever connected to the drawbar and extending radially outward of the spindle through the lever hole; a trigger fixed to the frame; a feed unit that reciprocates the ram, advances the ram toward a distal end to machine a workpiece, and retracts the ram toward a basal end to bring the lever into contact with the trigger for the drawbar to advance with respect to the spindle to open the collet.

A machine tool, includes: a frame; a hollow ram disposed on the frame in a reciprocable manner; a hollow spindle rotatably supported by the ram, the spindle including a spindle hole located at a distal end, and a spline hole located at a basal end; a guide block disposed in the spindle and having a guide hole extending along a center axis of the spindle; and a spindle drive shaft rotatably supported by the frame, the spindle drive shaft including a spline shaft that engages with the spline hole, and a support shaft disposed at a distal end of the spline shaft to be guided in sliding contact with the guide hole.

A spindle includes a housing, a bearing housed in the housing, a main shaft rotatably supported by the bearing, a collet chuck extending into a through hole of the main shaft to grip a machining tool and movable in an axial direction of the main shaft, a draw bar connected to the collet chuck, an air inlet above the bearing and through which air is introduced into the housing, an air passage defined in the housing such that the air introduced into the housing through the air inlet flows below the bearing, and an air outlet in the housing and below the bearing and through which the air flowing below the bearing is discharged out of the housing.