Abstract: A method and device for facilitating the replacement of a worn out section of a friction roller in a friction feeder with another section. The roller is fixedly mounted on a shaft adjacent to the feeder nip. In operation, the shaft is restricted from turning by a locking mechanism. The locking mechanism comprises a locking member and a blocking surface. The shaft has an extended shaft section for slideably mounting the locking member, which has a polygonal outer circumference. When the locking member is located adjacent to the blocking surface, it is restricted from rotating. But when the locking member is slid away from the blocking surface, it can be rotated to cause the shaft to rotate, thereby moving another section of the frictional surface on the friction roller to replace the worn out section near the nip.

Abstract: A method and device for locking and unlocking a print head assembly along a shaft in an addressing machine. The print head assembly is fixedly mounted on a locking mechanism, which comprises a cylindrical body slideably mounted on the shaft and a cam ring rotatably mounted over the cylindrical body. The cylindrical body has a slot for seating an elongated spline. When the locking mechanism is operated in a locking position, the inner circumference of the cam ring presses the spline against the shaft, preventing the cylindrical body from moving along the shaft. The cam ring has a relief on its inner circumference such that, when the cam ring is rotated to the unlocked position, the spline is partially seated in the relief, thereby reducing the pressure exerted by the spline against the shaft. As such, the position of the print head assembly can be adjusted.