Abstract: The print head includes a print head support, a pair of actuators on one side of the support, and wire guide supports on the opposite side of the print head support for clamping the actuators and wire guide supports to the print head support. The wire guide supports have diameters equal to the centerline-to-centerline spacing of the print wires. The print head support has a linear surface extending perpendicular to a plane passing along the edges of the wire guide supports. The print heads are aligned along a support member by securing the print head support to the support member with the tangent plane and linear surface engaging mutually perpendicular surfaces on the support member whereby the contact between the wire guide supports along the support member establishes the centerline-to-centerline spacing of the print wires.

Abstract: A ribbon movement controlling cartridge includes a smudge guard/ribbon guide which contains exposed ribbon in a fixed stationary position during cartridge transportation and storage. When the guide is engaged with a printhead, it releases ribbon passage therethrough and acts as a smudge guard/ribbon guide during normal cartridge usage. A Mobius loop forming structure (along a first path for fabric ribbons) includes a central aperture therethrough so as to alternately permit direct non-inverting ribbon passage through the same structure along a second path intersecting the first path, for carbon film-type ribbons. A limited usage metering and self-stopping mechanism insures against over-extended usage of the cartridge. A unique key locking tab arrangement permits a proper cartridge to be positively engaged with a printer while also permitting easy disengagement for cartridge removal and replacement.

Abstract: A dot matrix shuttle printer and/or a module therefore uses print wires of different lengths so as to achieve desired close packing of individual print wire actuators and correspondingly close wire-to-wire spacing of the print wires. To help maintain synchronization between the operation of all print wires, the longer ones include hollow sections so as to cause all the print wires to have substantially equal mass in spite of their differing lengths. The longer print wires include a hollow tube of stainless steel. A tip of wear resistant material is fixedly inserted at one end of the tube to effect impact printing.