Thread-cutting die head for powered pipe threader

A thread-cutting die head for a powered pipe threading machine, the thread-cutting die head comprising:

• a die carrier, defining a central axis, for supporting a plurality of thread-cutting dies for displacement relative to the central axis in a radially inward direction and radially outward direction;
• a cam plate coaxial with the die carrier including a plurality of cam members for engaging with the plurality of thread-cutting dies and displacing the cutting dies in the radially inward direction and radially outward direction in response to relative rotation between the cam plate and the die carrier;
• and
• a locking system including
• a positioning screw extending through an arcuate slot in the cam plate,
• a cam washer surrounding the positioning screw,
• a pin threaded to the positioning screw, and
• a cam handle including
• a cylindrical cam portion engaged with the cam washer and defining a rotational axis of the handle, and
• an aperture in which the pin is slidably received, the aperture defining a longitudinal axis that is offset from the rotational axis of the handle,
• wherein rotation of the cam handle in a first direction about the rotational axis is configured to impart a clamping force against the cam washer to lock the rotational position of the cam plate relative to the die carrier.