(57) A thermal transfer printing apparatus for printing an elongate continuous web W of
items. The apparatus comprises a frame structure having an imprinter 12 mounted thereon.
A plurality of idlers 40,41,42,43,44 supports the web of items and defines a path
of travel for the web. A segment of the path of travel is adjacent the imprinter and
its print head 25. A rockable arm 50 is connected to the frame structure and contacts
the web W along a top surface of the web at two locations 51,52. A first of the locations
51 is upstream of the print head and a second of the locations 52 is downstream of
the print head. The arm 50 is connected to the frame structure about a pivot point
54 and rocks about this pivot point during operation of the apparatus in a manner
similar to a "teeter-totter" or "seesaw". A stepper motor drives two drive rollers
45,46 thereby advancing the web. When a selected item is in a proper printing position
within the segment S of the path of travel adjacent the imprinter, air cylinders 30,31
actuate a nip 24 and the print head 25 against the drive rollers to maintain proper
tension within the selected item. The rockable arm 50 then rocks about its pivot point
54 and the stepper motor drives the drive rollers 45,46 to pull the selected item
past the print head 25 so that the item may be imprinted.
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