Printer carriage drive with movably mounted motor

Disclosed is an improved printer and carriage drive mechanism. The carriage motor is mounted at a first side of the printer chassis, and an idler pulley is mounted at a second side of the chassis. The carriage also has a pair of idler pulleys. A single flat smooth belt is attached to the first side of the chassis. From there, it passes over to and around one of the idler pulleys on the carriage, back to and around the motor pulley, across the print zone and around the idler pulley on the second side of the chassis, back to and around the other carriage idler pulley, and then back to the second side of the chassis, where it is attached. The motor is movably attached to the chassis and is tensioned by a spring. This mechanism provides for substantial mechanical advantage over common simple carriage drive mechanisms. A smaller, less expensive motor and a quieter flat smooth belt can be used. The motor is allowed to run at more optimal speeds and expensive ball bearings can be avoided in the motor and pulleys.