Shuttle counterbalance, cam oiler and flywheel motor for a printer.

摘要

In a printer (10) in which a shuttle (14) is driven in reciprocating fashion by a rotating cam (30), a counterbalance assembly (28) disposed on the opposite side of the cam from the shuttle (14) and having a cam follower (38) disposed along a common axis extending through the cam and a cam follower of the shuttle includes a mass in the form of a generally rectangular block (42) mounting the cam follower at one of a pair of opposite ends thereof. Reciprocating movement of the block in response to rotation of the cam is provided by a pair of flex pivots (48) coupled to opposite ends of a base (44) and extending upwardly and coupled to the opposite ends of the block. The end of the block opposite the cam follower receives a spring (54) disposed against a reference surface to bias the cam follower against the cam. A thin film of oil is maintained on the surface of the cam by an oiler (62) which includes a resilient leaf spring (128) mounted on the frame of the printer at one end thereof and resiliently biasing a porous sintered polyethylene element (124) containing a quantity of oil and mounted at an opposite end of the leaf spring against the surface of the cam. The cam is rotatably driven by a DC motor (36) having a rotor (34) coupled to the cam (30) and having a flywheel (32) integrally formed with the rotor.