Abstract: A pipe threader comprises a housing and a drive assembly including a motor and an output gear having a first plurality of teeth. A die holder defines a rotational axis and includes a gear member including an outer circumference with a second plurality of teeth engaged with the output gear. The gear member includes an inner circumference with a key recess. A lock ring is rotatable relative to the gear member and including a contact surface. A key is arranged in the key recess and a biasing member in the key recess and biasing the key toward the rotational axis. The lock ring is movable between a locked position, in which the contact surface inhibits the key from moving away from the rotational axis, and an unlocked position, in which the key is movable away from the rotational axis in response to insertion of a die into the die holder.

Abstract: An annular thread cutting die head for a power driven threading machine is comprised of an annular support plate assembly supporting a plurality of radially displaceable threading cutting dies spaced apart about the axis of the die head, and a cam plate assembly coaxial with and pivotal relative to the support plate assembly to radially displace the cutting dies. The cam plate assembly is spring biased to pivot relative to the support plate assembly in the direction to radially retract the cutting dies, and pivoting in the latter direction is controlled by a keeper mounted on the support plate assembly and engaging a keeper track on the cam plate assembly.