Transport mechanism and method for transporting a print medium in a printing system

Patent metadata

Field	Value
Publication number	US-9616689-B2
Application number	US-201514939840-A
Country	US
Kind code	B2
Filing date	Nov 12, 2015
Priority date	Nov 13, 2014
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

A transport mechanism and method are provided for transporting sheets of a print medium in a printing system. The transport mechanism includes a first conveyor device having a first conveyor body configured to hold a plurality of sheets of print medium and to convey the sheets along the transport path, and a transfer system including a second conveyor device having a second conveyor body configured to hold the sheets and to convey the sheets further along the transport path. The transfer system is configured to transfer the sheets from the first conveyor body to the second conveyor body in a transfer region. The second conveyor body is adjacent the first conveyor body in the transfer region, and the transfer system includes a suction device configured to provide an under-pressure at the second conveyor body for contactless transfer of the sheets from the first conveyor body to the second conveyor body.

First claim

The invention claimed is:

1. A transport mechanism for transporting sheets of a print medium along a transport path in a printing system, comprising:
a first conveyor device having a first conveyor body which is configured to hold a plurality of sheets of print medium and is movable to convey the sheets along the transport path; and
a transfer system comprising a second conveyor device having a second conveyor body which is configured to hold the sheets and is movable to convey the sheets further along the transport path, wherein the transfer system is configured to transfer the sheets from the first conveyor body to the second conveyor body in a transfer region,
wherein the second conveyor body is arranged adjacent the first conveyor body in the transfer region, and the transfer system is configured to provide a second under-pressure at the second conveyor body arranged for contactless transfer of the sheets from the first conveyor body to the second conveyor body,
wherein the second conveyor body has a second carrier surface configured to support the sheets thereon, and
wherein the second conveyor device provides regions on the second carrier surface of different air-flow from the second under-pressure, the second carrier surface including a region of relatively higher suction force or air-flow arranged in a central region of the second carrier surface with respect to the transport path arranged for attracting a centre portion of the each sheet with respect to the transport path towards the second conveyor body in the transfer region.

2. A transport mechanism according to claim 1 , wherein said regions on the second carrier surface further include a region of relatively low air-flow for attracting lateral side portions of each sheet, said region of relatively low air-flow surrounding said central region of relatively higher suction force or air-flow in a direction lateral to the transport path.

3. A transport mechanism according to claim 1 , wherein the second under-pressure at the second conveyor body overcomes a holding force on the sheets of print medium on the first conveyor body.

4. A transport mechanism according to claim 1 , wherein the transfer system is configured to release a holding force on the sheets of print medium on the first conveyor body at the transfer region.

5. A transport mechanism according to claim 4 , wherein the first conveyor device is configured to provide a first under-pressure at the first conveyor body to hold the sheets fixed in position on the first conveyor body as it conveys the plurality of sheets along the transport path, and wherein the transfer system is configured to reduce or exclude the first under-pressure in the transfer region.

6. A transport mechanism according to claim 5 , wherein the transfer system includes a shield configured to shield a section of the first conveyor body from the first under-pressure.

7. A transport mechanism according to claim 6 , wherein the shield comprises one or more baffle members arranged within the first conveyor body, such that the one or more baffle members shield or shutter a section of the first conveyor body in the transfer region.

8. A transport mechanism according to claim 1 , wherein the first conveyor body is provided as a drum member and an outer periphery or circumference of the drum member forms a first carrier surface for supporting the plurality of sheets thereon, wherein the first conveyor body is configured to provide a first under-pressure within the drum member, and wherein the drum member is rotatable about an axis to convey the sheets along the transport path.

9. A transport mechanism according to claim 8 , wherein the first carrier surface includes holes or apertures which communicate the first under-pressure and which are at least partially covered by the plurality of sheets of print medium held fixed in position on the first carrier surface.

10. A transport mechanism according to claim 1 , wherein the transfer system provides the second under-pressure at the second conveyor body to hold the sheets fixed in position thereon as the second conveyor body conveys the sheets further along the transport path.

11. A transport mechanism according to claim 10 , wherein the second carrier surface includes holes or apertures to communicate the second under-pressure provided by the transfer system to hold the sheets on the second conveyor body as it conveys the sheets further along the transport path.

12. A printing system comprising a transport mechanism according to claim 1 .

13. A transport mechanism according to claim 1 , wherein the transfer system comprises a centrifugal fan or an axial fan.

14. A method of transporting sheets of print medium in a printing system, comprising:
holding a plurality of sheets of a print medium on a first conveyor body in a first conveyor device and rotating the first conveyor body to convey the sheets along a transport path;
providing a second conveyor device having a second conveyor body for holding the sheets;
releasing the sheets of print medium from the first conveyor body in a transfer region; and
attracting the sheets to the second conveyor body of the second conveyor device in the transfer region to contactless transfer the sheets from the first conveyor body to the second conveyor body and Moving the second conveyor body to convey the sheets further along the transport path,
wherein the second conveyor body has a second carrier surface configured to support the sheets thereon,
wherein the step of attracting the sheets to the second conveyor body comprises providing a second suction force or second under-pressure in or at the second conveyor body, wherein the second conveyor device provides regions of different air-flow from the second under-pressure over the second carrier surface, and
wherein in a central region of the second carrier surface with respect to the transport path the sheet is attracted by a relatively higher suction force or air-flow to attract a centre portion of the sheet with respect to the transport path towards the second conveyor body.

15. A method according to claim 14 , wherein the step of holding the plurality of sheets on the first conveyor body includes providing a first suction force or first under-pressure to hold the sheets fixed in position on the first conveyor body as it moves to convey the sheets along a transport path; and
wherein the step of releasing the sheets of print medium from the first conveyor body comprises reducing, excluding or eliminating the first under-pressure in the transfer region.

16. A method according to claim 14 , wherein the step of attracting the sheets to the second conveyor body further comprises providing the second suction force or second under-pressure in or at the second conveyor body to hold the sheets fixed in position on the second carrier surface of the second conveyor body as it moves to convey the sheets further along the transport path.

Assignees

• Océ-Technologies B V

Inventors

• La Vos Peter G
• Van Beek Albert M
• Boerstal Hendricus G J
• Kersten Stan H P
• Gruntjens Marinus T W

Classifications

• B65H2301/517

  Drying material · CPC title

• B65H5/224

  by suction belts (B65H11/005 takes precedence) · CPC title

• B65H2301/4474

  Pair of cooperating moving elements as rollers, belts forming nip into which material is transported · CPC title

• B65H2404/2693

  Arrangement of belts on movable frame · CPC title

• B41J13/22

  Clamps or grippers · CPC title