Sheet-fed printing unit configured as a screen printing unit

Patent metadata

Field	Value
Publication number	US-11926142-B2
Application number	US-202218029936-A
Country	US
Kind code	B2
Filing date	Feb 15, 2022
Priority date	Mar 9, 2021
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

In some examples, a screen printing unit includes a screen printing forme cylinder, an impression cylinder, and at least one further rotational transport body. A fixing element of the impression cylinder includes inner and outer contact surfaces for clamping sheets. The inner contact surface has a base radius as a distance from an axis of rotation of the impression cylinder. A cylinder barrel of the impression cylinder has a supporting surface for sheets that includes an impression portion having a constant barrel radius, which extends over at least 170° about the axis of rotation of the impression cylinder and the barrel radius is larger than the base radius. A fixing element of the further rotational transport body includes an inner and an outer contact surface for clamping sheets. The inner contact surface includes the base radius as a distance from an axis of rotation of the further rotational transport body.

First claim

The invention claimed is:

1. A sheet-fed printing unit ( 700 ), the sheet-fed printing unit ( 700 ) being configured as a screen printing unit ( 700 ) and comprising at least one screen printing forme cylinder ( 752 ) and at least one impression cylinder ( 708 ) cooperating therewith, and at least one further rotational transport body ( 709 ; 711 ; 712 ; 713 ), and a fixing element of the at least one impression cylinder ( 708 ) having an inner contact surface ( 748 ) and an outer contact surface ( 749 ), which are arranged so as to cooperate for clamping sheets ( 02 ), and the inner contact surface ( 748 ) being at least partially located at a distance from an axis of rotation ( 716 ) of the at least one impression cylinder ( 708 ) which corresponds to a base radius (R 0 ), and a cylinder barrel ( 741 ) of the at least one impression cylinder ( 708 ) having a supporting surface ( 744 ) for sheets ( 02 ) that includes at least one impression portion ( 746 ) having a constant barrel radius (R 1 ), which extends over an angle of at least 170° about the axis of rotation ( 716 ) of the at least one impression cylinder ( 708 ), and the barrel radius (R 1 ) being larger than the base radius (R 0 ), and a fixing element of the at least one further rotational transport body ( 709 ; 711 ; 712 ; 713 ) having an inner contact surface and an outer contact surface, which are arranged so as to cooperate for clamping sheets ( 02 ), and the inner contact surface being at least partially located at a distance from an axis of rotation ( 717 ; 718 ; 719 ; 721 ) of the at least one further rotational transport body ( 709 ; 711 ; 712 ; 713 ) which corresponds to the base radius (R 0 ).

2. The sheet-fed printing unit according to claim 1 , characterized in that the at least one further rotational transport body ( 709 ; 711 ; 712 ; 713 ) is configured as an alignment cylinder ( 709 ), which comprises a plurality of elements inducing a magnetic field in the area of its outer circumference.

3. The sheet-fed printing unit according to claim 2 , characterized in that at least one blower drum ( 712 ) is arranged so as to form a transfer point ( 732 ; 733 ) with the at least one impression cylinder ( 708 ) and so as to form another transfer point ( 733 ; 734 ) with the alignment cylinder ( 709 ).

4. The sheet-fed printing unit according to claim 3 , characterized in that a fixing element of the at least one blower drum ( 712 ) has an inner contact surface and an outer contact surface, which are arranged so as to cooperate for clamping sheets ( 02 ), and the inner contact surface is at least partially located at a distance from an axis of rotation ( 719 ) of the at least one blower drum ( 712 ) which corresponds to the base radius (R 0 ), and/or characterized in that at least one sheet guide device and at least one sheet blower device are assigned to the at least one blower drum ( 712 ), and the at least one sheet guide device has at least one inner surface, whose shape corresponds to a section of a cylinder shell having an axis that is identical to the axis of rotation ( 719 ) of the at least one blower drum ( 712 ), and the inner surface is located at a distance from the axis of rotation ( 719 ) of the at least one blower drum ( 712 ) which is larger than the base radius (R 0 ), and/or characterized in that the at least one sheet blower device is used to generate a flow of gas that is directed from the inside against the inner surface of the at least one sheet guide device, and/or characterized in that at least one pre-alignment device ( 767 ) is arranged, in a stationary manner, in a region of the at least one blower drum ( 712 ), which is an integral part of a respective alignment device ( 771 ) and comprises at least one solenoid and/or permanent magnet.

5. The sheet-fed printing unit according to claim 1 , characterized in that the barrel radius (R 1 ) is smaller than twice the base radius (R 0 ).

6. The sheet-fed printing unit according to claim 1 , characterized in that:
the base radius (R 0 ) is at least 125 mm, and no more than 225 mm; or
the base radius (R 0 ) is at least 125 mm and no more than 200 mm; or
the base radius (R 0 ) is at least 125 mm and no more than 190 mm; or
the base radius (R 0 ) is at least 125 mm and no more than 188 mm; or
the base radius (R 0 ) is at least 175 mm, and no more than 225 mm; or
the base radius (R 0 ) is at least 175 mm and no more than 200 mm; or
the base radius (R 0 ) is at least 175 mm and no more than 190 mm; or
the base radius (R 0 ) is at least 175 mm and no more than 188 mm; or
the base radius (R 0 ) is at least 185 mm, and no more than 225 mm; or
the base radius (R 0 ) is at least 185 mm and no more than 200 mm; or
the base radius (R 0 ) is at least 185 mm and no more than 190 mm; or
the base radius (R 0 ) is at least 185 mm and no more than 188 mm; or
the base radius (R 0 ) is at least 187 mm, and no more than 225 mm; or
the base radius (R 0 ) is at least 187 mm and no more than 200 mm; or
the base radius (R 0 ) is at least 187 mm and no more than 190 mm; or
the base radius (R 0 ) is at least 187 mm and no more than 188 mm; or
the base radius (R 0 ) is at least 125 mm; or
the base radius (R 0 ) is at least 175 mm; or
the base radius (R 0 ) is at least 185 mm; or
the base radius (R 0 ) is at least 187 mm; or
the base radius (R 0 ) is no more than 225 mm; or
the base radius (R 0 ) is no more than 200 mm; or
the base radius (R 0 ) is no more than 190 mm; or
the base radius (R 0 ) is no more than 188 mm.

7. The sheet-fed printing unit according to claim 1 , characterized in that:
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 0.5 mm and by no more than 10 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 1 mm and by no more than 10 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 2 mm and by no more than 10 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 0.5 mm and by no more than 5 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 1 mm and by no more than 5 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 2 mm and by no more than 5 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 0.5 mm and by no more than 4 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 1 mm and by no more than 4 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 2 mm and by no more than 4 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 0.5 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 1 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by at least 2 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by no more than 10 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by no more than 5 mm; or
the barrel radius (R 1 ) is larger than the base radius (R 0 ) by no more than 4 mm.

8. The sheet-fed printing unit according to claim 1 , characterized in that the at least one impression cylinder ( 708 ) has a smaller radius at least in a region of a cylinder channel ( 742 ) than in a region of the cylinder barrel ( 741 ).

9. The sheet-fed printing unit according to claim 1 , characterized in that the at least one screen printing forme cylinder ( 752 ) has an effective screen radius (R 2 ), and that the effective screen radius (R 2 ) is smaller than the barrel radius (R 1 ) and smaller than the base radius (R 0 ), and that the effective screen radius (R 2 ) is larger than half the ba

Assignees

• Koenig & Bauer Ag

Inventors

• Müller Michael
• Palme Martin

Classifications

• B41F15/0809 Primary

  with cylindrical or belt-like screens · CPC title

• B41F15/34

  Screens, Frames; Holders therefor · CPC title

• B41F21/102

  with pneumatic means (B41F21/108 takes precedence) · CPC title

• B41F33/02

  Arrangements of indicating devices, e.g. counters · CPC title

• B41F21/04 Primary

  Grippers ({B41F21/08, B41F21/10} B41F21/12, B41F21/14 take precedence) · CPC title