AUTOMATIC METHOD AND DEVICE FOR CUTTING SUBSTRATES HAVING PRINTED IMAGES

• US 20190152735A1
• Filed: 05/11/2017
• Published: 05/23/2019
• Est. Priority Date: 05/25/2016
• Status: Active Grant

• Current Assignee: Fotoba International S.R.L.
• Original Assignee: Fotoba International S.R.L.
• Inventors: MADDALON, Valter
• Granted Patent: US 10,640,321 B2
• Time in Patent Office: Days
• CPC Class Codes: B26D 1/105 for thin material, e.g. for sheets, strips or the like
• CPC Class Codes: B26D 2011/005 in combination with different kind of cutters, e.g. two serial slitters in combination with a transversal cutter
• CPC Class Codes: B26D 5/007 Control means comprising cameras, vision or image processing systems
• CPC Class Codes: B41F 13/58 lengthwise
• CPC Class Codes: B41F 13/60 crosswise
• CPC Class Codes: B41J 11/663 Controlling cutting, cutting resulting in special shapes of the cutting line, e.g. controlling cutting positions, e.g. for cutting in the immediate vicinity of a printed image
• CPC Class Codes: B41J 11/68 cutting parallel to the direction of paper feed
• CPC Class Codes: B41J 11/706 using a cutting tool mounted on a reciprocating carrier
• CPC Class Codes: B65H 16/005 Dispensers, i.e. machines for unwinding only parts of web roll
• CPC Class Codes: B65H 2301/5151 transversally to feeding direction
• CPC Class Codes: B65H 2301/5155 longitudinally
• CPC Class Codes: B65H 35/0086 using movable cutting elements
• CPC Class Codes: B65H 35/02 from or with longitudinal slitters or perforators
• CPC Class Codes: B65H 35/04 from or with transverse cutters or perforators

Abstract

The invention relates to a method for cutting substrates with printed images in an automatic cutting device provided with means for correcting alignment errors based on the detection of longitudinal and transverse cutting marks. The longitudinal cutting marks (LM) are provided with a discontinuity (N) arranged upstream of each transverse cutting mark (TM) with respect to a feeding direction (F) of a substrate (S) and spaced therefrom by a predefined known measure (d). The automatic cutting device has a first optical unit configured to detect the transverse cutting marks (TM) and a second optical unit configured to detect the discontinuities (N) in the longitudinal cutting mark (LM). Since the velocity of the substrate is known, the control system activates the first optical unit when the transverse cutting mark (TM) actually passed underneath it.

Claims

1. A method for cutting substrates comprising printed images by way of an automatic cutting device provided with means for the correction of alignment errors, said method comprising the steps of:

i) Printing a plurality of images on a substrate;

ii) Printing a longitudinal cutting mark close to an edge of said substrate and parallel to edges of said images in a longitudinal or feeding direction and a plurality of transverse cutting marks perpendicular to said longitudinal cutting mark, said transverse cutting marks being arranged between consecutive images printed on said substrate;

iii) Providing an automatic cutting device having a first optical unit configured for the detection of said transverse cutting marks; and

iv) Feeding the substrate into said automatic cutting device;

said longitudinal cutting mark is printed such that it has a discontinuity arranged upstream of each transverse cutting mark with respect to said feeding direction, said discontinuity being spaced from the respective transverse cutting mark by a predefined known measure;

the automatic cutting device is provided with a second optical unit configured for the detection of said discontinuities in the longitudinal cutting mark; and

a control system of the automatic cutting device is configured such that, when the second optical unit detects the discontinuities of the longitudinal cutting mark, the first optical unit is selectively activated for the detection of transverse cut marks printed on the substrate.

2. The cutting method according to claim 1, wherein the discontinuities of the longitudinal cutting mark are indentations.

3. The cutting method according to claim 1, wherein the second optical unit is configured to detect the discontinuities of the longitudinal cutting mark as well as to monitor the latter along the feeding direction and the correction of alignment errors of the substrate.

4. An automatic device for cutting substrates comprising printed images, said device comprising:

i) one or more longitudinal cutting units configured to allow cutting of a substrate in a feeding direction;

ii) a transverse cutting unit configured to allow cutting of said substrate in a transverse direction perpendicular to said feeding direction;

iii) correction means for the correction of alignment errors of a substrate, wherein said correction means comprise a first optical unit arranged in said transverse direction and configured for the detection of transverse cutting marks printed on said substrate; and

iv) a control system to which said first optical unit is operatively connected;

further comprising a second optical unit that is operatively connected to said control system and is provided with two detection points, said second optical unit being arranged at one end of said automatic device in the transverse direction in such a way that, in use, said two detection points are arranged opposite each other with respect to a longitudinal cutting mark printed along an edge of the substrate fed in the feeding direction; and

said control system is configured to activate the first optical unit selectively on the basis of signals indicative of discontinuities in said longitudinal cutting mark received from said second optical unit.

5. The automatic device according to claim 4, further comprising a third optical unit arranged at one end of said automatic device in the transverse direction and configured for monitoring the longitudinal cutting mark.

6. The automatic device according to claim 5, wherein the third optical unit is arranged close to the second optical unit.

7. The automatic device according to claim 4, wherein the second optical unit is configured for both the detection of the discontinuities of the longitudinal cutting mark and its monitoring in the feeding direction, as well as for the correction of alignment errors of the substrate.