Selective roller inker means for high speed selective type drum

Claim 1

A printer apparatus for printing characters on a medium, comprising: a printing drUm rotated at a constant speed; first and second pluralities of characters mounted on first and second portions, respectively, of said drum to form a ring of characters thereon; said drum having a plurality of said rings of characters in parallel relationship with one another and positioned axially along the rotating axis of said drum; each said plurality of characters including alpha-numerics and rectangular bars, with the long dimension of each said bar being oriented transversely to the rotating axis of said drum, and each said bar being angularly displaced from one another and also axially displaced from one another to form a shuttling pattern in each said ring of characters to enable the bars to be printed on said medium in side by side relationship with the long dimension of said bars being transverse to the rotating axis of said drum; a printing station, and feed means for feeding the medium thereto in a direction which is perpendicular to the rotating axis of said drum; first inking means for inking with a first ink the first portion of the drum containing said first plurality of characters and comprising: a cam member fixed to rotate with said drum, and having a low camming surface and a high camming surface; an inking roller and an ink supply roller for supplying said first ink to said inking roller; and lever actuating means having a follower arm riding on said camming surfaces of said cam member so as to move said inking roller into engagement with said first portion of the drum only when said arm rides on said low camming surface; second inking means for inking with a second ink the second portion of the drum containing said second plurality of characters and comprising: a second cam member fixed to rotate with said drum, and having a low camming surface and a high camming surface; a second inking roller and an ink supply roller for supplying said second ink to said inking roller; and second lever actuating means having a second follower arm riding on said camming surfaces of said second cam member so as to move said second inking roller into engagement with said second portion of the drum only when said second arm rides on said low camming surface of said second cam member; hammer printing means located at said station and including print hammers spaced in an axial direction along said drum, with one print hammer being provided for each said ring of characters for striking the corresponding characters on said drum in response to a control means so as to selectively print characters in said first and second inks on said drum; said bars within each said plurality of characters being spaced over a fixed distance as measured in an axial direction, and each said print hammer having a fixed width as measured in said axial direction, with the width of each said print hammer being slightly less than said fixed distance; and mounting means for slidably mounting said hammer printing means for movement between first and second positions along a line parallel to the rotating axis of the drum in timed relationship therewith to enable each said print hammer to strike all its associated alpha-numerics and rectangular bars.