A feed unit for drilling and/or tapping comprising a housing, a quill in the housing movable between retracted and extended positions, the quill rotationally supporting a spindle for carrying a rotary tool, a screw for moving the quill between said positions, a ball spline shaft in the housing coaxial with the spindle, a ball spline nut having recirculating steel balls rolling in raceways on the ball spline shaft, the spindle radially supporting the ball spline shaft within the quill with zero clearance through the ball spline nut, rotation of the ball spline shaft being imparted to the spindle through the ball spline nut.

A machine tool for implementing machining with rotation, the machine tool includes a first rotor, an enclosure, a first rail, a second rail, and a coupler. The first rotor rotates about a rotational axis. The first rotor is surrounded with the enclosure. The first rail is disposed on the first rotor. The second rail is disposed on the enclosure so as to be brought into alignment with the first rail at a rotational position. The coupler moves along the first rail and the second rail. The coupler is to engage with the first rail and the second rail in a first state and to engage with the second rail without engaging with the first rail in a second state.

To accurately perform movement control of a moving body, a machine tool includes a feed driver that moves a moving body in the machine tool, a feedback controller that feedback-controls the feed driver in accordance with a state variable, a friction compensator that, to compensate for rolling friction that occurs in the feed driver, adds, in advance, a friction compensation value obtained from measurement data of rolling friction or a friction compensation value calculated using a rolling friction model to a command value to be input to the feed driver, and a reverse response reducer that reduces, using the state variable of the feedback controller, a reverse response that occurs due to addition of the friction compensation value.

To accurately perform movement control of a moving body, a machine tool includes a feed driver that moves a moving body in the machine tool, a feedback controller that feedback-controls the feed driver in accordance with a state variable, a friction compensator that, to compensate for rolling friction that occurs in the feed driver, adds, in advance, a friction compensation value obtained from measurement data of rolling friction or a friction compensation value calculated using a rolling friction model to a command value to be input to the feed driver, and a reverse response reducer that reduces, using the state variable of the feedback controller, a reverse response that occurs due to addition of the friction compensation value.

A motor rear-mounted direct drive spindle includes a spindle housing; a mandrel that is rotatably disposed within the spindle housing; a bearing; and a torque motor. The bearing includes a first bearing and a second bearing that provide radial and axial support to the mandrel, the first bearing and the second bearing are disposed inside the spindle housing, one end of the mandrel extends outside the spindle housing, the torque motor and the spindle housing are axially aligned, the torque motor includes a rotor and a stator, the end of the mandrel located outside the spindle housing is inserted into and connected to an end of the rotor, and the rotor is fixedly connected to the mandrel. In a motor rear-mounted direct drive spindle, a motor with the motor rear-mounted spindle is entirely exposed outside, thus distancing the motor from a mandrel.

A motor rear-mounted direct drive spindle includes a spindle housing; a mandrel that is rotatably disposed within the spindle housing; a bearing; and a torque motor. The bearing includes a first bearing and a second bearing that provide radial and axial support to the mandrel, the first bearing and the second bearing are disposed inside the spindle housing, one end of the mandrel extends outside the spindle housing, the torque motor and the spindle housing are axially aligned, the torque motor includes a rotor and a stator, the end of the mandrel located outside the spindle housing is inserted into and connected to an end of the rotor, and the rotor is fixedly connected to the mandrel. In a motor rear-mounted direct drive spindle, a motor with the motor rear-mounted spindle is entirely exposed outside, thus distancing the motor from a mandrel.

A spindle turning device includes a turning portion and a main body portion. The turning portion includes a rotatable main spindle. The main body portion supports the turning portion turnably around a pivot shaft inclined with respect to an axis line of the main spindle. The main body portion includes a motor that turnably drives the turning portion and a reducer. In a turning position of the turning portion where the axis line of the main spindle faces downward in a vertical direction, a lowermost surface of the main body portion is located above a lowermost surface of the turning portion. The motor is arranged in the main body portion below an axis line of the pivot shaft.

A spindle turning device includes a turning portion and a main body portion. The turning portion includes a rotatable main spindle. The main body portion supports the turning portion turnably around a pivot shaft inclined with respect to an axis line of the main spindle. The main body portion includes a motor that turnably drives the turning portion and a reducer. In a turning position of the turning portion where the axis line of the main spindle faces downward in a vertical direction, a lowermost surface of the main body portion is located above a lowermost surface of the turning portion. The motor is arranged in the main body portion below an axis line of the pivot shaft.