Method for checking the quality of flat workpieces and device for carrying out said method

• US 7,073,444 B2
• Filed: 05/14/2004
• Issued: 07/11/2006
• Est. Priority Date: 05/16/2003
• Status: Expired due to Fees

• Current Assignee: Bobst SA (JBF Finance SA)
• Original Assignee: Bobst SA (JBF Finance SA)
• Inventors: Strasser, Georg, Alonso, Jeronimo
• Primary Examiner(s): Hirshfeld, Andrew H.
• Assistant Examiner(s): Culler, Jill E.
• Application Number:
  US10/846,716
• Publication Number:
  US 20040251176A1
• Time in Patent Office: 788 Days
• Field of Search: None
• US Class Current: 101/484
• CPC Class Codes: B31B 50/006 Controlling; Regulating; Measuring; Improving safety
• CPC Class Codes: B31B 50/066 from above a magazine
• CPC Class Codes: B65H 29/62 diverting faulty articles from the main streams control devices detecting faulty articles B65H43/04
• CPC Class Codes: G06T 2207/30124 Fabrics; Textile; Paper
• CPC Class Codes: G06T 7/0004 Industrial image inspection

Abstract

Method and apparatus for checking the quality of blanks processed with a machine processing blanks of at least a certain type, comprising: carrying out a registering for said possible blank types, feeding a register parameter (n) defining a required number of blanks per pile, loading a pile of blanks into a device, conveying the blanks of the pile throughout a registering area ensuring the scanning of the printing and/or diecutting quality of said blanks, defining which type the registered blank is the better related, stripping the blank if it has printing and/or diecutting defects, and piling up the registered blanks that were not stripped so as to pile up a new pile until it comprises n blanks, and repeating the steps, and apparatus for the foregoing.

Claims

1. A method for checking the quality of workpieces processed by a printing or a diecutting machine which produces workpieces of at least one type, the method comprising:

registering each of the types of workpieces in a pile of the workpieces;

infeeding a register parameter corresponding to a selected number of workpieces in the pile;

loading at least one pile of the workpieces in an infeed station for checking the quality of the workpieces;

conveying at least one workpiece of the one pile at the infeed station through a registering area and scanning the printing or diecutting quality of the registered workpiece, at the registering area, defining which of the different types of the workpieces to which the workpiece being scanned is most closely related;

scanning the workpiece for possible printing or diecutting defects in the registered workpiece;

stripping any registered workpiece which has printing or diecutting defects that are scanned so that they are not piled in a delivery station;

piling the workpieces that have not been stripped into a new pile in a delivery station.

2. The method of claim 1, further comprising when all of the workpieces in the pile have been registered, loading at least one second pile of workpieces to be registered and continuing the process hereof on the new pile of workpieces until the number of workpieces in the new pile is the same as the registered parameter value of the number of workpieces in the pile;

unloading the second pile in the delivery station and continuing with loading subsequent piles in the same process.

3. The method of claim 1, wherein the registering of different types of workpieces is performed using a reference pile having as many reference workpieces therein of acceptable quality as there are different types of workpieces.

4. The method of claim 3, wherein the step of registering all of the different types of workpieces comprises loading of the reference pile of workpieces into an infeed station,

conveying the first reference workpiece through the registering area;

storing the image of the reference workpiece,

piling the reference workpieces in the delivery station; and

repeating the foregoing process through each of the reference workpieces in the reference pile.

5. The method of claim 4, further comprising:

bringing up the images of the same type of reference workpieces in order to bring up only one reference workpiece per type of the workpieces.

6. The method of claim 1, further comprising automatically loading the piles in an infeed station, and automatically unloading the piles from the delivery station.

7. The method of claim 6, wherein the printing and diecutting machine operates at a particular rate with reference to the workpieces and the automatic loading of piles is coordinated with the printing and diecutting machine operation.

8. The method of claim 1, wherein the workpieces are flat workpieces and the quality of the flat workpieces is being checked.

9. Apparatus for checking the quality of workpieces comprising:

a printing or diecutting machine for workpieces including at least one type of workpiece;

an infeed station for feeding the workpieces to the printing or diecutting machine;

a registering area for registering the different types of workpieces in the pile of workpieces in the infeed station;

apparatus for scanning the workpieces and for registering a parameter related to a required number of workpieces per pile;

after the infeed station, a registering area for scanning the printing and diecutting quality of the registered workpieces in the registering area and for defining which one of the types of workpieces that the registered workpieces is most related to;

a scanner for scanning possible printing and diecutting defects in the registered workpiece;

a stripper for stripping those registered workpieces which have printing or diecutting defects detected and stripping them away from the path of the workpieces,

a delivery station for receiving a pile of the workpieces that have not been stripped;

and a conveyor for conveying the workpieces from the infeed station past the infeed area, past the scanning device, past the registering area, past the station at which detected defective workpieces are stripped, and to the delivery stations.

10. The apparatus of claim 9, wherein upstream of the scanning device and the registering device the conveyor includes an alignment area including an aligning device for aligning the workpieces.

11. The apparatus of claim 9, further comprising a central control device for controlling the operations of the other elements of the apparatus.