Inking roller and apparatus and method for printing using such roller

An apparatus for printing indicia on sheet material comprising, a base, a support on said base for supporting a printing plate having raised characters, said support having an elongated rail which receives an edge of said printing plate in abutting relation thereagainst, an inking roller, said inking roller having an outer cylindrical surface and comprising an inking portion defined by a tubular porous sintered mass of particles bonded together into a homogeneous reticulated open pore structure having pores throughout, said pores containing ink and being interconnected and forming continuous ink passages between said outer surface and an inner surface of said structure, said inking roller having a non-inking portion defined by an ink impermeable member disposed on said cylindrical structure and defining at least a part of said outer surface, said structure having an integral reduced diameter cylindrical portion at one end thereof, said member being in the form of a tubular sleeve having a cylindrical outside surface which defines said part of said outer surface, said sleeve being fixed to said reduced diameter cylindrical portion, said roller having substantially uniform deflection characteristics across its entire axial length, and means supporting said inking roller for rectilinear movement with said noninking portion being supported solely by said rail with only said sheet material interposed therebetween and said roller exuding ink from its inking portion on said sheet material in response to backup pressure exerted by said raised characters through said sheet material to print corresponding indicia thereon, said uniform deflection characteristics and action of said non-inking portion assuring inking of said sheet material free of both smearing and wrinkling thereof.

A method of printing indicia on sheet material in a substantially non-smearing manner comprising the steps of, supporting a printing plate having raised characters horizontally in a rigid manner with an edge of said printing plate against a rigid elongated horizontal rail, providing an inking roller having an outer cylindrical surface and comprising an inking portion defined by a tubular porous sintered mass of particles bonded together into a homogeneous reticulated open pored structure having pores throughout, said pores containing ink and being interconnected and forming continuous passages between said outer cylindrical surface and an inner surface of said structure, said inking roller having a non-inking portion defined by an ink impermeable member disposed on said cylindrical structure and defining at least part of said outer surface, said structure having an integral reduced diameter cylindrical portion at one end thereof, said member being in the form of a tubular sleeve having a cylindrical outside surface which defines said part of said outer surface, said sleeve being fixed to said reduced diameter cylindrical portion, said roller having substantially uniform deflection characteristics across its entire axial length, supporting said inking roller for rectilinear movement with said noninking portion being supported solely by said rail with only said sheet material interposed therebetween with said roller exuding ink from its inking portion on said sheet material in response to backup pressure exerted by said raised characters through said sheet material to print corresponding indicia thereon, said uniform deflection characteristics and action of said non-inking portion assuring inking of said sheet material in said non-smearing manner and free of wrinkling thereof.