Embodiments of this aspect of the invention may include one or more of the following features.

The clamping member is a c-shaped clamp. The actuator is an eccentric rod located in a channel defined by the base. A plurality of registration pins are connected to the base and movable relative to the base to selectively engage a substrate held by the clamp.

According to another aspect of the invention, a clamp for registering a variety of substrates having differently spaced registration notches to a printing assembly includes a clamp base defining a surface and a plurality of spaced registration pins connected to the clamp base. The registration pins are independently selectively deployable to extend from the base surface and engage the spaced registration notches of a substrate. Only those registration pins having spacing ther¬ebetween which corresponds with the spacing of the sub¬strate notches are deployed.

Embodiments of this aspect of the invention may include one or more of the following features.

The base defines a plurality of registration holes for rotatably receiving the registration pins. Each pin defines a cam surface. The base defines a mating surface extending into each of the registration holes. The mating surface resides against the cam surface such that rotation of the pin causes the pin to move between a deployed position in which the pin extends into the substrate notch and a non-deployed position in which the pin is spaced from the substrate notch.

Embodiments of this aspect of the invention may include a spring for biasing the registration pin toward the deployed position.

According to another aspect of the invention, a method for registering a variety of substrates having differently spaced registration notches to a printing assembly includes provid¬ing a plurality of spaced registration pins connected to a clamp of the printer assembly, and independently selectively deploying only those registration pins having spacing ther¬ebetween which corresponds with the spacing of the sub¬strate notches to extend from the clamp and engage the spaced notches of the substrate.

Among other advantages, the printing drum is easy to adjust for clamping of different sized printing plates to the drum. The disks of the drum provide continuous support of the printing plate. The drum can be made to any desired length to hold various width plates and to hold more than one plate at a time. The plurality of deployable registration pins allow different sized plates to be precisely located on the drum.

Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a printing drum assembly of the invention.

FIG. 2A shows a leading edge assembly of the printing drum assembly of FIG. 1; and FIG. 2B shows a trailing edge assembly of the printing drum assembly of FIG. 1.

FIG. 3A is an end view of the printing drum assembly of FIG. 1 shown with a printing plate mounted to the drum assembly; and FIG. 3B is a perspective view of disk of the drum assembly.

FIG. 4 is an exploded view of the printing drum assembly of FIG. 1.

FIG. 5 is a cross-sectional side view of single disk of the printing drum assembly of FIG. 1, taken along lines 5-5 in FIG. 3A.

FIG. 6A is a perspective view of a balancing disk for use with the printing drum assembly of FIG. 1; and FIG. 6B is an exploded view of the balancing disk.

FIG. 7A is an end view of a clamp of the printing drum assembly of FIG. 1 shown in a clamping position; and FIG. 7B is an end view of the clamp of FIG. 7A shown in an open position.

FIG. 8 shows a printing plate for use with the printing drum assembly of FIG. 1.

FIG. 9 is a perspective view of a registration pin of the clamp of FIG. 7.

FIG. 10A is a perspective view of a trailing edge assembly lock; and FIG. 10B is an exploded view of the trailing edge assembly lock of FIG. 10A,