Inspection system for in-line inspection of printed material produced on an intaglio printing press

Patent metadata

Field	Value
Publication number	US-10059093-B2
Application number	US-201113806896-A
Country	US
Kind code	B2
Filing date	Jun 24, 2011
Priority date	Jun 25, 2010
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

There is described an inspection system ( 50 ) for in-line inspection of sheet or web material on an intaglio printing press, wherein the inspection system comprises an optical quality control apparatus for carrying out inspection of a printed area on a printed side of the sheet or web material, the optical quality control apparatus including a camera system ( 55 ) with one or more camera units each comprising at least one line-scan camera ( 56 ) for scanning and acquiring an image of the printed area while the sheet or web material is being transported in the intaglio printing press past the camera system ( 55 ). A location of the at least one line-scan camera ( 56 ) in the intaglio printing press along a delivery path of the sheet or web material is such that cyclical vibrations that spread periodically throughout the intaglio printing press during operation of the intaglio printing press do not occur while the camera system ( 55 ) is scanning the printed area of the sheet or web material and acquiring a complete image of the printed area.

First claim

The invention claimed is:

1. An intaglio printing press comprising an inspection system for in-line inspection of sheet or web material on the intaglio printing press,
wherein the inspection system comprises an optical quality control apparatus for carrying out inspection of a printed area on a printed side of the sheet or web material, the optical quality control apparatus including a camera system with one or more camera units each comprising at least one line-scan camera for scanning and acquiring an image of the printed area while the sheet or web material is being transported in the intaglio printing press past the camera system,
wherein a location of the at least one line-scan camera in the intaglio printing press along a delivery path of the sheet or web material is such that cyclical vibrations that spread periodically throughout the intaglio printing press during operation of the intaglio printing press do not occur while the camera system is scanning the printed area of the sheet or web material and acquiring a complete image of the printed area,
wherein the camera system comprises a single camera unit disposed transversely to the path of the sheet or web material for scanning an entire width of the printed area of the sheet or web material,
wherein a distance along the delivery path between a printing location where printing of the sheet or web material occurs and an inspection location where the camera system acquires an image of the printed area of the sheet or web material is an integer multiple of the distance separating two successive printed samples of the sheet or web material, which is the distance between a leading edge of a sheet or web material to a leading edge of an immediately following sheet or web material, and the distance includes a length of an impression cylinder pit,
wherein the intaglio printing press is designed for processing sheet material, and wherein the camera system is located along the path of a sheet conveyor system comprising a pair of endless chains driving spaced-apart gripper bars for holding a leading edge of the sheet material, and
wherein the intaglio printing press further comprises at least one sheet-guiding member for supporting a backside of the sheet material opposite the printed side in the region of the inspection location.

2. The intaglio printing press as defined in claim 1 , further comprising an intermediate transfer unit for guiding the sheet or web material away from an impression cylinder of the intaglio printing press to the circumference of a downstream located inspection cylinder or drum, which inspection cylinder or drum guides the sheet or web material in front of and past the camera system.

3. An intaglio printing press comprising an inspection system for in-line inspection of sheet or web material on the intaglio printing press,
wherein the inspection system comprises an optical quality control apparatus for carrying out inspection of a printed area on a printed side of the sheet or web material, the optical quality control apparatus including a camera system with one or more camera units each comprising at least one line-scan camera for scanning and acquiring an image of the printed area while the sheet or web material is being transported in the intaglio printing press past the camera system,
wherein the inspection system comprises an intermediate transfer unit for guiding the sheet or web material away from an impression cylinder of the intaglio printing press to the circumference of a downstream located inspection cylinder or drum, which inspection cylinder or drum guides the sheet or web material in front of and past the camera system, the intermediate transfer unit being interposed between the impression cylinder and the inspection cylinder or drum,
wherein the camera system comprises a single camera unit disposed transversely to the path of the sheet or web material for scanning an entire width of the printed area of the sheet or web material,
wherein a distance along the delivery path between a printing location where printing of the sheet or web material occurs on the impression cylinder and an inspection location where the camera system acquires an image of the printed area of the sheet or web material on the inspection cylinder or drum is an integer multiple of the distance separating two successive printed samples of the sheet or web material which includes a length of a cylinder pit of the impression cylinder, thereby ensuring that cyclical vibrations that spread periodically throughout the intaglio printing press during operation of the intaglio printing press do not occur while the camera system is scanning the printed area of the sheet or web material and acquiring a complete image of the printed area, and
wherein the intermediate transfer unit guides the sheet or web material along a curved trajectory forming an arc of a circle, and wherein a radius of the curved trajectory and a radius of the inspection cylinder or drum are each a fraction of the radius of the impression cylinder of the intaglio printing press.

4. The intaglio printing press as defined in claim 2 , wherein the intermediate transfer unit guides the sheet or web material along a curved trajectory forming an arc of a circle, and wherein a radius of the curved trajectory and a radius of the inspection cylinder or drum are each a fraction of the radius of the impression cylinder of the intaglio printing press.

5. The intaglio printing press as defined in claim 4 , wherein the impression cylinder exhibits n segments and wherein the radiuses of the curved trajectory and of the inspection cylinder or drum are respectively 1/n and 2/n of the radius of the impression cylinder.

6. The intaglio printing press as defined in claim 2 , wherein the intermediate transfer unit is arranged to avoid any contact with the printed side of the sheet or web material which is freshly printed on the intaglio printing press.

7. The intaglio printing press as defined in claim 6 , designed for processing sheet material, wherein the intermediate transfer unit is designed as a rotating gripper system comprising at least one gripper bar for holding a leading edge of the sheet material and transporting the sheet material along a trajectory forming an arc of a circle.

8. The intaglio printing press as defined in claim 6 , further comprising a suction unit located next to the path of the sheet or web material and upstream of the inspection cylinder or drum for drawing a backside of the sheet or web material opposite the printed side while the sheet or web material is being guided to the circumference of the inspection cylinder or drum.

9. The intaglio printing press as defined in claim 8 , wherein the suction unit extends along substantially the entire path between a location where the sheet or web material leaves the circumference of the impression cylinder and a location where the sheet or web material is conveyed to the inspection cylinder or drum.

10. The intaglio printing press as defined in claim 8 , further comprising a blowing unit for blowing air against the printed side of the sheet or web material and pushing the backside of the sheet or web material towards an aspiration surface of the suction unit.

11. The intaglio printing press as defined in claim 8 , wherein the suction unit is moveable between a working position, next to the path of the sheet or web material, and a maintenance position, retracted away from the working position.

12. The intaglio printing press as defined in claim 6 , further comprising a guide member located next to the path of the sheet or web material for supporting a backside of the sheet or web material opposite the printed side wh

Assignees

• Schaede Johannes Georg
• Tuerke Thomas
• Schwitzky Rolf Volkmar
• Kba Notasys Sa

Inventors

• Schaede Johannes Georg
• Türke Thomas
• Schwitzky Rolf Volkmar

Classifications

• B41F21/10

  Combinations of transfer drums and grippers · CPC title

• B41F21/08

  Combinations of endless conveyors and grippers · CPC title

• B41F9/06

  Details · CPC title

• B41F33/0036 Primary

  Devices for scanning or checking the printed matter for quality control · CPC title

• B41F22/00

  Means preventing smudging of machine parts or printed articles (B41F23/00 takes precedence) · CPC title