Sheet-transporting drum and printing machine having the sheet-transporting drum

Patent metadata

Field	Value
Publication number	US-9738472-B2
Application number	US-201615134598-A
Country	US
Kind code	B2
Filing date	Apr 21, 2016
Priority date	May 6, 2015
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A sheet-transporting drum includes sheet-supporting areas each being formed of a first comb segment and a second comb segment having segment teeth. At least one of the comb segments is rotatable for adaptation to a sheet format. A mechanical leading-edge gripper is provided on the first comb segment and a pneumatic trailing-edge gripper is provided on the second comb segment. A mechanical trailing-edge gripper is additionally disposed on the second comb segment and is deactivatable in particular by format adjustments. This advantageously allows either the trailing edge of a sheet to be securely held down mechanically or a full-bleed print to be applied to the sheet when the trailing edge of the sheet is held down pneumatically. A sheet-fed printing machine is also provided.

First claim

The invention claimed is:

1. A sheet-transporting drum in a sheet-processing machine, the sheet-transporting drum comprising:
at least one sheet-supporting area formed of a first comb segment and a second comb segment each having respective segment teeth;
at least one of said first and second comb segments being rotatable for adaptation to a sheet format;
a mechanical leading-edge gripper being disposed on said first comb segment;
a pneumatic trailing-edge gripper being disposed on said second comb segment; and
a deactivatable mechanical trailing-edge gripper being disposed on said second comb segment, said pneumatic trailing-edge gripper being disposed between said mechanical trailing-edge gripper on said second comb segment and tips of said segment teeth on said second comb segment.

2. The sheet-transporting drum according to claim 1 , which further comprises an adjustment device for pivoting said second comb segment relative to said first comb segment to align either said pneumatic trailing-edge gripper or said mechanical trailing-edge gripper on said second comb segment with a trailing edge of a respective sheet to be transported.

3. The sheet-transporting drum according to claim 2 , wherein said adjustment device has an adjustment drive connected to said second comb segment and a control unit.

4. The sheet-transporting drum according to claim 1 , wherein at least one of said mechanical trailing-edge gripper or said mechanical leading-edge gripper has a gripper bar with grippers fixed thereto, said gripper bar extending over a width of the sheet-transporting drum.

5. The sheet-transporting drum according to claim 4 , wherein each said mechanical gripper has respective flat gripper fingers and gripper pads.

6. The sheet-transporting drum according to claim 1 , wherein said pneumatic trailing-edge gripper is a suction groove.

7. The sheet-transporting drum according to claim 1 , wherein the sheet-transporting drum is a jetting cylinder.

8. A sheet-fed printing machine, comprising:
a sheet-transporting drum according to claim 1 .

9. A digital sheet-fed printing machine, comprising:
a sheet-transporting drum according to claim 1 ; and
inkjet heads disposed above said sheet-transporting drum.

Assignees

• Heidelberger Druckmasch Ag

Inventors

• Rothaug Juergen
• Juenger Arno
• Maul Albert
• Goll Sven
• Schmidt Thomas
• Knabe Alexander
• Conzelmann Daniel
• Dolz Wolfgang
• Mueller Kai Oskar
• Schroeder Raimund

Classifications

• B41F21/10 Primary

  Combinations of transfer drums and grippers · CPC title

• B65H5/08 Primary

  by grippers, e.g. suction grippers · CPC title

• B65H2405/50

  Gripping means · CPC title

• B41J13/223

  on rotatable drums · CPC title

• B41F21/104 Primary

  Gripper details (B41F21/102 takes precedence) · CPC title