A METHOD AND A DEVICE FOR GENERATING A SEQUENCE OF CUTTING PLANS FOR CUTTING OUT A SEQUENCE OF GLASS PIECES IN A SEQUENCE OF GLASS SHEETS

Abstract

A method for generating a sequence of cutting plans for cutting out a sequence P of glass pieces in a sequence F of glass sheets, the glass pieces to be stacked according to order and/or positioning requirements on one or more stands C.sub.k, includes retrieving information relating to the location and nature of faults in each of the glass sheets of the sequence F; defining an optimization criterion ; generating, implemented by computer, of one or more sequences S.sub.i of cutting plans PD.sub.ij for the glass sheets according to the location of the faults in each of the glass sheets and while satisfying the order and/or positioning requirements of the glass pieces for each stand C.sub.k; selecting, implemented by computer, of one of the sequences S.sub.i of cutting plans PD.sub.ij according to the optimization criterion .

Claims

1. A method for generating a sequence of cutting plans for cutting out a sequence P of glass pieces in a sequence F of glass sheets, said glass pieces being intended to be stacked according to order and/or positioning requirements on one or more stands C.sub.k, said method comprising: a. retrieving information relating to the location and nature of faults in each of the glass sheets of the sequence F; b. defining an optimization criterion ; c. generating, implemented by computer, one or more sequences S.sub.i of cutting plans PD.sub.ij for the glass sheets according to the location of the faults in each of the glass sheets and while satisfying the order and/or positioning requirements of the glass pieces for each stand C.sub.k; d. selecting, implemented by computer, one of the sequences S.sub.i of cutting plans PD.sub.ij according to the optimization criterion .

2. The method for generating a sequence of cutting plans as claimed in claim 1, wherein the optimization criterion is chosen from among a criterion of minimum total surface area loss or a criterion of minimum number of glass sheets cut.

3. The method for generating a sequence of cutting plans as claimed in claim 1, wherein the order and/or positioning requirements are chosen from among the orientation of the glass pieces in each stand C.sub.k and/or the order of the glass pieces in each stand C.sub.k.

4. The method for generating a sequence of cutting plans as claimed in claim 1, wherein the cutting plans comprise several hierarchical cutting levels.

5. The method for generating a sequence of cutting plans as claimed in claim 1, wherein the generation of the sequence or sequences S.sub.i of cutting plans PD.sub.ij for the glass sheets is carried out such that glass pieces to be cut contain faults satisfying a severity criterion defined beforehand.

6. The method for generating a sequence of cutting plans as claimed in claim 5, wherein the severity criterion is chosen from among a fault size criterion, a criterion of fault density on the glass sheet, a fault nature criterion or an optical alteration criterion, alone or in combination.

7. The method for generating a sequence of cutting plans as claimed in claim 1, wherein the generation of sequences S.sub.i of cutting plans PD.sub.ij of step (c) and/or the selection of one of the sequences S.sub.i of cutting plans PD.sub.ij of step (d) are carried out with the aid of an exploratory dendrogram, a heuristic or metaheuristic search method, linear optimization by Lagrange duality, or dynamic programming.

8. The method for generating a sequence of cutting plans as claimed in claim 1, the wherein a duration required for executing the step for generating the sequence or sequences S.sub.i of cutting plans PD.sub.ij for the glass sheets does not exceed a predefined duration.

9. The method for generating a sequence of cutting plans as claimed in claim 1, wherein the information retrieval of step (a) comprises the reading, with the aid of an acquisition system, of a symbol forming a code able to be read via the edge face of each of the glass sheets, said code containing an identifier associated with the information relating to the location and nature of the faults in the glass sheet.

10. The method for generating a sequence of cutting plans as claimed in claim 9, wherein said identifier is contained in a database which contains the information relating to the location and nature of the faults in the glass sheet.

11. The method for generating a sequence of cutting plans as claimed in claim 1, wherein steps (a), (b) and (c) are implemented according to a cloud computing model.

12. A cutting method comprising carrying out a method for generating a sequence of cutting plans as claimed in claim 1, then (e) cutting out glass pieces in the glass sheets according to the sequence S.sub.i of cutting plans PD.sub.ij that is selected at step (d) of said generation method.

13. A computer program comprising instructions for the execution of the steps of the method for generating a sequence of cutting plans as claimed in claim 1.

14. A non-transitory storage medium readable by computer on which there is recorded a computer program comprising instructions for executing the steps of the method for generating a sequence of cutting plans as claimed in claim 1.

15. A device for generating a sequence of cutting plans for cutting out a sequence P of glass pieces in a sequence F of glass sheets, each of the glass pieces being intended to be stacked according to order and/or positioning requirements on one or more stands C.sub.k, said device comprising the following modules: a. a module for retrieving information relating to the location and nature of faults in each of the glass sheets of the sequence F; b. a module for defining an optimization criterion ; c. a module for generating one or more sequences S.sub.i of cutting plans PD.sub.ij for the glass sheets according to the location of faults in each of the glass sheets and satisfying the order and/or positioning requirements of the glass pieces for each stand C.sub.k; and d. a module for selecting one of the sequences S.sub.i of cutting plans PD.sub.ij according to the optimization criterion .

16. The device for generating a sequence of cutting plans as claimed in claim 15, wherein the module for retrieving information relating to the location of faults in each of the glass sheets of the sequence F is a module for reading a symbol forming a code able to be read via the edge face of each of the glass sheets, said code containing an identifier associated with the information relating to the location and nature of the faults in the glass sheet.

17. The device for generating a sequence of cutting plans as claimed in claim 16, further comprising a module for direct or indirect telecommunication with a storage medium readable by computer containing a database containing, for each identifier, the information relating to the location of faults in each glass sheet of the sequence F.

18. A cutting device comprising a device for generating a sequence of cutting plans as claimed in claim 15, and a module for cutting out glass pieces in the glass sheets according to the selected sequence S.sub.i of cutting plans PD.sub.ij.

Description

[0043] The features of the invention are illustrated by the drawings described hereafter.

[0044] FIG. 1 is a schematic representation of an example cutting plan for a glass sheet.

[0045] FIG. 2 is a graphic representation, in the form of a logic diagram, of several sequences S.sub.i of cutting plans PD.sub.ij for sheets, satisfying the order and positioning requirements of the glass pieces for each stand C.sub.k.

[0046] FIG. 3 is a schematic representation of an example cutting plan obtained using a method without cutting optimization.

[0047] FIG. 4 is a graphic representation of an example cutting plan obtained using the method according to the invention.

[0048] FIG. 5 is a schematic representation of a first embodiment of the cutting device according to the invention.

[0049] FIG. 6 is a schematic representation of a second embodiment of the cutting device according to the invention.

[0050] An example cutting plan PD1 for a glass sheet PLF1 is schematically represented in FIG. 1. This plan provides for cutting out five pieces of glass P11, P12, P13, P21 and P22 with three hierarchical cutting levels: two cutouts d1 and d2 of hierarchical level 1, two cutouts d3 and d4 of hierarchical level 2, and a cutout d5 of hierarchical level 3.

[0051] In FIG. 2, there is represented a simplified example of the generation of several sequences S.sub.i of cutting plans PD.sub.ij for cutting out three pieces 11, 12 and 21 in a sequence of two glass sheets PLF1 and PLF2 according to the location of the faults (not represented) and while satisfying the order, positioning and cutting requirements for the glass pieces for each stand C.sub.k. In this example, the four sequences S.sub.1 to S.sub.4 each contain 12 cutting plans, PD.sub.1,1 to PD.sub.4,12. For the purposes of readability of the drawing, only the cutting plans PD.sub.1,1 to PD.sub.1,12 are represented, and the cutting plans PD.sub.2,1 to PD.sub.4,12 of the sequences S.sub.2 to S.sub.4 are represented by dotted-line rectangles.

[0052] The sequences are obtained using an exploratory dendrogram. A first sequence S.sub.i is generated by first of all placing a first piece 11 on the lower lefthand edge of the first glass sheet PLF1 according to a first orientation. Next, a second piece 12 is placed according to two possible orientations in contact with the two free edges of the first piece 11 in order to construct four cutting plans PD.sub.1,1 to PD.sub.1,4. The same operation is carried out for the piece 21 by substituting it for the piece 12 in order to construct four other cutting plans PD.sub.1,5 to PD.sub.1,8. The construction is continued with the third piece 21 for the cutting plans PD.sub.1,1 to PD.sub.1,4 or the third piece 12 for the cutting plans PD.sub.1,5 to PD.sub.1,8. The cutting plans obtained are not represented in the drawing.

[0053] Alternatively, the pieces 12 and 21 are placed on the lower lefthand edge of the second glass sheet PLF2 according to two orientations in order to construct the cutting plans PD.sub.1,9 to PD.sub.1,10 and PD.sub.1,11 to PD.sub.1,12. The construction of the cutting plans is continued with the third remaining piece according to the same method.

[0054] The sequence S.sub.2 is generated according to the same method from the first piece 11 placed in a second direction on the lower lefthand edge of the glass sheet PLF1. Likewise, the same method is used to generate the sequences S.sub.3 and S.sub.4 by replacing the piece 11 by the piece 21 as first piece.

[0055] At the end of the generation of the sequences, the sequence of cutting plans that satisfies the optimization criterion is selected.

[0056] An example cutting plan 300 for a glass sheet 301 and obtained using a method without cutting optimization is represented in FIG. 3. This method does not take into account faults 302, 303 and 304 present in the glass sheet when the cutting plan is generated. These faults 302, 303 and 304 are located in pieces P02, P22 and P27 respectively. After cutting, these pieces are unusable and must be recut in the next glass sheet. This causes a cascade of changes in the sequence of cutting plans and results in significant losses of time and glass.

[0057] FIG. 4 schematically represents a cutting plan 400 obtained using the method according to the invention for the glass sheet 301 of FIG. 3. By taking into account the faults before the cutting plan is generated, the latter can be optimized so as to place these faults in the offcuts. With reference to FIG. 4, certain pieces have been replaced by others, while satisfying the order and/or positioning requirements of the glass pieces for each stand C.sub.k. In particular, the pieces P01, P02, P03 and P04 have been removed and replaced by the pieces P29 and P30 which are compatible with the order and/or positioning requirements.

[0058] An example of a first embodiment of a cutting device according to the invention is schematically represented in FIG. 5. It comprises a module 504 for retrieving information relating to the location of faults, 502a and 502b, in each of the glass sheets, 501a, of a sequence 500 of glass sheets 501a-501f. This module comprises a read module, for example a camera 504a, which reads a symbol forming a code 503 on the edge face of each of the glass sheets, 501a. This code 503 is transmitted to a processing system 504b for the code image acquired by the camera. The system extracts the identifier encoded in the symbol and retrieves the information relating to the location and nature of the faults 502a and 502b in the glass sheet 501a by consulting a database 505 which contains this identifier.

[0059] This information is then transmitted to a computer 506 which contains the following modules: [0060] a module 506a for defining an optimization criterion ; [0061] a module 506b for generating one or more sequences S.sub.i of cutting plans PD.sub.ij for the glass sheets according to the location of the faults in each of the glass sheets and satisfying the order and/or positioning requirements of the glass pieces for each stand C.sub.k; [0062] a module 506c for selecting one of the sequences S.sub.i of cutting plans PD.sub.ij according to the optimization criterion .

[0063] These modules are instantiated in the form of objects by a computer program or computer software from classes in the random access memory, possibly assisted by a virtual memory, of the computer 506.

[0064] The selected sequence S.sub.i of cutting plans PD.sub.ij is transmitted to a cutting module 507 comprising a cutting table 507b and a computer 507a for controlling the cutting table. The computer 507b sends instructions to the cutting table in order to cut the sequence 500 of glass sheets according to the selected sequence S.sub.i of cutting plans PD.sub.ij. By way of illustrative example, only the glass sheet 501a is represented on the cutting table. The cutting plan is not represented.

[0065] FIG. 6 schematically represents a second embodiment of the cutting device according to the invention. This device differs from that of FIG. 5 by the fact that the computers 504b, 506 and 507 are replaced by a single computer 600 telecommunicating with a cloud computing infrastructure 601. This infrastructure contains: [0066] a database 601a containing information relating to the location and nature of the faults in each of the glass sheets of the sequence 500; [0067] a module 601b for defining an optimization criterion ; [0068] a module 601c for generating one or more sequences S.sub.i of cutting plans PD.sub.ij for the glass sheets according to the location of the faults in each of the glass sheets and satisfying the order and/or positioning requirements of the glass pieces for each stand C.sub.k; [0069] a module 601d for selecting one of the sequences S.sub.i of cutting plans PD.sub.ij according to the optimization criterion .

[0070] The read module, for example a camera 504a, reads a symbol forming a code 503 on the edge face of each of the glass sheets, for example 501a. This code 503 is transmitted to a processing system 600 for the code image acquired by the camera. The system extracts the identifier encoded in the symbol and transmits it to the cloud 601. Once extracted from the database 601a by virtue of the identifier, the information relating to the location and nature of the faults 502a and 502b in the glass sheet 501a is transmitted to the generation module 601c. The sequence S.sub.i of cutting plans PD.sub.ij that is selected by the module 601d is then transmitted to the computer 600. The latter conveys instructions to the cutting table in order to cut the sequence 500 of glass sheets according to the selected sequence S.sub.i of cutting plans PD.sub.ij. By way of illustrative example, only the glass sheet 501a is represented on the cutting table. The cutting plan is not represented.

[0071] This embodiment is advantageous since it enables computing resources to be shared between operators using the method of the invention. They are thus exempt from having a local computing infrastructure.