113 located in a cam hole 105 defined in base 74 has a cam

member 114 that extends into groove 104. A cam hole 105

is associated with each registration hole 99.

Clockwise rotation of registration pin 100 results in

55 retraction of pin 100 into hole 99 as groove 104 rides along cam 114. Likewise, counterclockwise rotation of registration pin 100 results in pin 100 moving to its extended position. When pin 100 is turned fully clockwise 90 degrees, cam 114 sits in a dentation 116 which holds pin 100 in its retracted

60 position. When pin 100 is turned fully counterclockwise, cam 114 sits in an indentation 118 which holds the pin in its extended position.

Pin 100 defines a central bore 108 which extends from a base 110 of the pin to below a top 112 of the pin. A spring

65 111 located in bore 108 biases pin 100 toward its extended position. The upward pressure exerted on the pin by the spring aids in maintaining cam 114 in indentation 116 or 118

until the user pushes down against the spring and rotates pin 100 to release the cam from the indentation.

Pins 100 include either a circular crown 120 (FIG. 7) or a racetrack crown 120a (FIG. 9). Crowns 120, 120a each define a slot 121 for receiving a screwdriver to rotate the pin. Circular crown 120 locates registration hole 28A of printing plate 24 in both the lateral and longitudinal directions, i.e., in the direction of the length of plate 24 and in the direction of width of plate 24. Racetrack crown 120a locates regis¬tration hole 120b in only in one direction, i.e., along the length of plate 24 but not along the width of plate 24. The combination of the circular and rectangular crowned pins insures that plate 24 is supported (kinematically restrained) in both the lateral and longitudinal directions while allowing enough play along the width of plate 24 to prevent warping.

Other embodiments are within the scope of the following claims.

For example, leading edge assembly 32 and trailing edge assembly 34 can include a greater or less number of disks. Referring to FIG. 11, a drum assembly 410 having nine disks 412a for the leading edge assembly 432 and eight disks 412b for the trailing edge assembly 434 are particularly advanta-geous for mounting of the various size printing plates to the drum.

In addition to the standard registration pins 100, which typically measure 10 mm across, the leading edge clamp can include a smaller set of pins that measure 6 mm across. These smaller pins 100 support a plate having smaller registration holes punched into the leading edge. The smaller configuration allows registration holes to be punched into sheets having perforations along the leading edges without interfering with the perforations.

The clamp includes several registration pin configurations to accommodate different size plates. For example, 10 mm pins having 220 mm spacing 400 mm spacing and 425 mm spacings, and 6 mm pins having a 220 mm spacing can be are incorporated. The pins are preferably made of stainless steel.

Referring to FIG. 12, a drum assembly 310 includes a leading edge assembly 132 with nine disks 12a, a first trailing edge assembly 134a with four disks 12b, and a second trailing edge assembly 134b with four disks 12c. Two trailing edge assemblies are independently rotatable with respect to leading edge assembly 132 such that two plates 24 of different lengths can be mounted to drum assembly 310. Up to, e.g., two twelve inch wide plates can be mounted to drum assembly 310.

What is claimed is:

1. A printer drum having an axis of rotation, comprising:

a leading edge assembly for holding a first end of a substrate, the leading edge assembly including a lead¬ing edge clamp and a first plurality of interconnected disks, and

a trailing edge assembly for holding a second end of; the substrate, the trailing edge assembly including a trail¬ing edge clamp and a second plurality of interconnected disks, the second plurality of disks being interleaved with the first plurality of disks and rotatable relative to the first plurality of disks about the axis of rotation, 打印机滚筒英文文献和中文翻译(6):http://www.youerw.com/fanyi/lunwen_61842.html