Flow-restricted printing cylinder for a removable printing sleeve

• US 20020162467A1
• Filed: 04/25/2002
• Published: 11/07/2002
• Est. Priority Date: 01/22/2001
• Status: Active Grant

• Current Assignee: Shanghai Electric (Group) Corporation (City of Shanghai)
• Original Assignee: Heidelberger Druckmaschinen Ag
• Inventors: Vrotacoe, James Brian, Palmatier, Roland Thomas
• Granted Patent: US 6,725,775 B2
• Time in Patent Office: Days
• US Class Current: 101/375
• CPC Class Codes: B41F 30/04 attaching to transfer cylinders
• CPC Class Codes: B41P 2227/20 Means enabling or facilitating exchange of tubular printing or impression members, e.g. printing sleeves, blankets attaching cylindrical printing formes B41F27/105

Abstract

A printing cylinder for accepting an axially-removable printing sleeve includes a cylinder body having an outer surface, the outer surface having at least one hole and a supply line in the cylinder body for supplying fluid to the at least one hole. The supply line has at least one flow restrictor designed to alter fluid flow as a function of the at least one hole being covered by an axially-removable printing sleeve. Also provided is a printing press having two such cylinders and a common pressure source. A method for axially removing a printing sleeve over a printing cylinder includes the steps of applying fluid pressure to an inside of a printing sleeve located on a printing cylinder through holes at a work side end of the printing cylinder and through other holes between the holes at the work side end and a gear side end of the printing cylinder, sliding the printing sleeve in a direction of the work side end of the printing cylinder, and automatically restricting flow through the other holes when the printing sleeve no longer is located over the other holes.

Claims

1. A printing cylinder for accepting an axially-movable printing sleeve comprising:

a cylinder body having an outer surface, the outer surface having at least one hole; and

a supply line in the cylinder body for supplying fluid to the at least one hole, the supply line having at least one flow restrictor designed to alter fluid flow as a function of an axial position of the axially-movable printing sleeve.

2. The printing cylinder as recited in claim 1 wherein the fluid is air.

3. The printing cylinder as recited in claim 1 wherein the flow restrictor includes a valve, the valve as a function of the axial position of the printing sleeve moving between an open position and a closed position where the fluid flow is reduced from the fluid flow in the open position.

4. The printing cylinder as recited in claim 3 wherein the valve is a ball-valve.

5. The printing cylinder as recited in claim 1 wherein the flow restrictor creates vortices when the at least one hole in uncovered.

6. The printing cylinder as recited in claim 1 wherein the outer surface further has a plurality of other holes at a work side end of the printing cylinder, the at least one hole located axially between the other holes and a gear side end of the printing cylinder.

7. The printing cylinder as recited in claim 6 wherein the plurality of other holes include another supply line having at least one other flow restrictor for the other holes.

8. The printing cylinder as recited in claim 1 wherein the flow restrictor includes a plurality of opposing fins, tips of opposing fins being spaced so as to form a free-flow channel.

9. The printing cylinder as recited in claim 1 wherein the at least one hole is spaced closer to a gear side of the printing cylinder.

10. The printing cylinder as recited in claim 1 wherein the at least one hole includes a plurality of holes and the at least one flow restrictor includes a flow restrictor for each hole.

11. The printing cylinder as recited in claim 10 wherein the outer surface has a second set of holes for a second axially-movable printing sleeve, the second set of holes having second flow restrictors.

12. The printing cylinder as recited in claim 1 wherein the printing cylinder is a blanket cylinder.

14. The method as recited in claim 13 wherein the flow restrictor includes a valve.

15. The method as recited in claim 13 wherein the automatically restricting step includes forming vortices in a supply line for the other holes when the printing sleeve is not over the hole.

16. The method as recited in claim 13 wherein the printing sleeve is a blanket.

13. A method for axially positioning a printing sleeve over a printing cylinder comprising the steps of:

applying fluid pressure to an inside of a printing sleeve located on a printing cylinder through at least one hole of the printing cylinder;

moving the printing sleeve axially with respect to the printing cylinder; and

automatically restricting fluid flow through the hole using a flow restrictor, the flow restrictor altering the fluid flow as a function of an axial position of the printing sleeve on the printing cylinder.