Label printer

A printer for printing on the end label in a strip of label stock having laterally extending rows of perforations spaced along said strip and defining a plurality of labels, and subsequently bursting the end label from the strip of label stock at the row of perforations separating it from the adjacent trailing label, comprising:

• printer means for printing on a label at a print station,
• means for transporting said end label past a print station for printing on said end label and, thereafter, for positioning said strip with the row of perforations separating said end label from the adjacent trailing label being located at a reference point,
• strip retarding means, positioned between said reference point and said print station, for engaging said adjacent trailing label near the lateral edges thereof, and restricting further movement thereof,
• bursting roller means, on the opposite side of said reference point from said strip retarding means, for applying a bursting force to said end label, and
• means for engaging the central portion of said adjacent trailing label while said strip retarding means restricts movement of said adjacent trailing label, such that bursting of said end label from said strip of label stock is facilitated, said means for engaging the central portion of said adjacent trailing label including a member movable into contact with said adjacent trailing label on the side thereof bearing said printing only when said label is to be engaged.

A printer for printing both human readable and machine readable indicia on labels in a strip of label stock as the strip is advanced along a supply path past a print station, comprising:

• means providing a supply of label stock, rotatable print drum means mounted at a print station and defining a plurality of raised portions corresponding to human readable and machine readable indicia,
• means for rotating said print drum means,
• print hammer means, positioned at said print station on the opposite side of said supply path from said print drum means, for striking said label stock to produce printing thereon by said print drum means,
• a pair of label advancing rollers, positioned on opposite sides of said supply path between said print station and said label stock supply, for engaging said label stock and transporting said label stock toward said print station,
• a pair of label tensioning rollers, having a radius slightly greater than that of said label advancing rollers, positioned on the opposite side of said print station from said label advancing rollers, said label tensioning rollers being positioned on opposite sides of said supply path for engaging said label stock,
• means for rotating said label advancing rollers and said label tensioning rollers at substantially the same angular velocity, whereby the tangential velocity of said label tensioning rollers is slightly greater than the tangential velocity of said label advancing rollers and said label stock is maintained in tension at said print station, and
• means for providing a substantially larger stock engaging force between said pair of label tensioning rollers than between said pair of label advancing rollers, whereby slippage occurs between said pair of label advancing rollers and said label stock.

A label printer for printing at a print station both human readable and machine readable bar code indicia over a substantial portion of the end label in a strip of perforated label stock, comprising:

• supply means providing a strip of label stock having laterally extending perforation lines spaced along said strip and defining a plurality of labels, each of which is to be separated from said strip after printing,
• label advancing and retracting rollers, between said supply means and said print station, for engaging opposite sides of said label stock to advance the label stock through said print station during printing of the end label thereof and to retract the stock after the end label has been separated from said strip, thereby presenting the next following label in position for printing close to its leading edge,
• label tensioning rollers, positioned on the opposite side of said print station from said label advancing rollers, for engaging opposite sides of said end label after said label has been partially printed and while it is being transported through said print station,
• printer means for printing only human readable indicia on said end label during travel of its leading edge from said print station to said label tensioning rollers, and for printing said machine readable bar code indicia on said end label only after the label is engaged by said label tensioning rollers, and
• roller drive means for rotating all of said rollers, said label tensioning rollers being rotated at a tangential velocity greater than that of said label advancing and retracting rollers, thereby maintaining said end label under tension during printing of said machine readable bar code indicia thereon.