Imprinting machine

A machine for imprinting indicia on thermoplastic corrugated tubing having alternating peaks and valleys comprising a framework, means on the framework for guiding corrugated tubing along a predetermined path of travel, motivating means connected to the framework constructed and arranged to continuously move the tubing along its path of travel, and imprinting means mounted on the framework adjacent the path of travel of the tubing for selective movement into and out of engagement with the exterior surface of the tubing, the imprinting means including a print wheel with spaced apart teeth at the periphery thereof arranged to mesh with the valleys of the corrugated tubing when the print wheel is in engagement therewith, conductive print type releasably secured to the print wheel at the periphery thereof between at least some of the spaced apart teeth, means for heating the print type, and means for selectively shifting the print wheel into engagement with the exterior surface of the corrugated tubing as it moves along its path of travel whereby the heated print type softens the thermoplastic of the peaks to thereby heat stamp the indicia of the type onto the corrugated tubing.