A rotating machining device for machining a work piece includes a support housing adapted for mounting on the work piece and a headstock rotatably mounted on the support housing about an axis. The headstock including an internal gear. A drive module is arranged to drive rotation of the headstock about the axis and at least one gear connection is formed between the internal gear and the drive module. The at least one gear connection is positioned radially inside of an outer diameter of the support housing to protect an operator from a pinch point associated with the at least one gear connection.

A method to control a power tool includes the following steps: ascertaining a first rotational speed of the transmission in a first gear; ascertaining a first rotational speed of the motor when the transmission has been put into a first gear; ascertaining the selection of a first gear on the basis of the ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; selecting the no-load state; ascertaining the selected no-load state on the basis of the ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; adapting the rotational speed of the motor to a second gear on the basis of a ratio of the rotational speed of the transmission and the rotational speed of the motor on the basis of a look-up table; and selecting a second gear.

A pipe machining apparatus includes a frame, a tool support mounted on a tool carrier which is mounted on the frame, and a gearing arrangement for rotating the frame, and a motor for rotating the gearing arrangement. The gearing arrangement includes a toothed pinion gear, a toothed backlash adjustment gear which is moveable relative to the pinion gear and being capable of being fixed in position relative to the pinion gear by a locking assembly, and a toothed bull gear affixed to the tool carrier. The teeth of the bull gear are capable of being engaged with the teeth of the pinion gear and with the teeth of the backlash adjustment gear, the bull gear to minimize backlash.

A rail drill drive train can include a common drive end between a single drive motor and a common gear. A speed train end can extend from the common gear to rotate the drill spindle. A feed train end can independently extend from the common gear to advance and retract the drill spindle. The speed train end can include a sprag gear so that, without unmeshing any gears, the drill spindle is not unnecessarily rotated in the reverse direction when the drive motor is reversed to retract the drill spindle. A rail drill control circuit and related sensors can enable automatic operation throughout the complete drilling cycle without any manual input from the user other than starting the cycle. Such a fully automatic drilling cycle can minimize overall cycle time to preserve battery life and can free the user to perform other tasks between drill moving and clamping operations.

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.