Patent ID: 8857943

Claim:
A duplex printer operable to print first and second sides of a double-sided label web as the label web is advanced longitudinally through the printer, with the first side of the label web presenting longitudinally spaced apart printable regions that are narrower than the width of the label web and devoid of adhesive, wherein the first side of the label web includes exposed adhesive located at least in part between and alongside printable regions, said duplex printer comprising: a printer frame that presents a web path along which the label web is permitted to pass longitudinally through the printer in a feed direction; first and second print heads supported relative to the printer frame and arranged to print respective sides of the label web as the label web makes a single pass along the web path, said first print head being shiftably mounted relative to the printer frame for movement into and out of a printing position, in which the first print head is operable to print within a respective one of the printable regions, said first print head being selectively shifted out of the printing position so as to avoid contact with the exposed adhesive during label web advancement; an actuator coupled to the first print head to effect shifting thereof; a controller operable to selectively control the actuator to shift the first print head into and out of the printing position; and a sensor operable to sense timing markers associated with the printable regions, as the label web is advanced along the web path, said controller being operably coupled to the sensor to control the actuator in response to sensing of each timing marker.