Drive means for a recording medium having liquid images thereon

A recording medium drive means in a printer for transporting a recording medium having liquid images on one surface thereof, the images being printed thereon by the printer with a recording liquid, the drive means comprising:

• a drive roller having a high friction surface and an axis of rotation, the drive roller being rotatably mounted beneath and tangent to a planar path of movement for a recording medium, the drive roller being oriented to move a recording medium along said path of movement;
• means for driving said drive roller;
• a toothed idler roller having an axis of rotation and spaced teeth with rounded distal ends extending from a cylindrical hub, the teeth having a predetermined height t from said hub and having a predetermined spacing between said teeth, the distal ends of said teeth having a surface which is not wet by the recording liquid, said idler roller being rotatably mounted above the recording medium planar path of movement with the idler roller axis being parallel to the drive roller axis;
• and
• means for urging said idler roller teeth into contact with the drive roller to thereby form a driving nip in which said idler roller teeth apply a force normal to the drive roller surface, so that when said recording medium is moved along said path of movement with an image-free surface in a direction to be contacted and driven by the idler roller, the idler roller teeth place a normal force on the recording medium surface containing liquid images thereon without forcing recording liquid into non-image areas and without damaging the recording medium surface.