Method of controlling a sheet metal machining line and apparatus for controlling the same

• US 5,880,965 A
• Filed: 12/05/1996
• Issued: 03/09/1999
• Est. Priority Date: 12/05/1996
• Status: Expired due to Term

• Current Assignee: Kaoru Nakamura, Nobuaki Tamura, Toshiyuki Koike
• Original Assignee: Kaoru Nakamura, Nobuaki Tamura, Toshiyuki Koike
• Inventors: Koike, Toshiyuki, Nakamura, Kaoru, Tamura, Nobuaki
• Primary Examiner(s): Gordon, Paul P.
• Assistant Examiner(s): Rao, Sheela S.
• Application Number:
  US08/759,527
• Time in Patent Office: 824 Days
• Field of Search: 364/185, 364/468.06, 364/468.08, 364/468.15, 364/468.16, 364/474.01, 364/474.16, 364/474.17, 364/468.07
• US Class Current: 700/175
• CPC Class Codes: B23Q 41/08 Features relating to maintenance of efficient operation
• CPC Class Codes: G05B 19/41865 characterised by job scheduling, process planning, material flow
• CPC Class Codes: G05B 2219/34393 Stop program if needed workpiece, tool or data lacks, misses
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A cell controller is provided that analyzes each unit machining schedule, which is referred to for manufacturing products, prior to the start of the assigned unit machining schedule. The data items in the schedule are analyzed include identification numbers of machining programs, the use or non-use of such identification numbers, the number of workpieces to be machined, and a presence or absence of predetermined procedures (e.g., for exchanging metal molds, etc.) that are referred to for manufacturing the products. An operator is notified of any foreseeable schedule alarm condition, that will force the operation of the line of manufacturing products of a specific item to be suspended, so that the operator may be informed of the situation in advance. The foreseeable schedule alarm condition may arise for reasons such as an insufficient number of available workpieces and/or preparatory work to be done (e.g., an exchange of metal molds, etc.).

Claims

1. A method of controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising unit machining schedules arranged in an order of machining operations to be carried out, each of said unit machining schedules being referred to for objects to be machined and containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating a completion or non-completion of machining operations specified in the unit machining schedule, so that supplied workpieces may be sequentially machined by predetermined machining operations according to the machining schedule, said method comprising:

assigning each unit machining schedule, indicated as being non-complete by a completion code, in accordance with a predetermined order;

determining the presence of a foreseeable schedule alarm condition, that will cause an operation of the sheet metal machining line to be suspended before or during the machining operation for the assigned unit machining schedule, by analyzing the data items of the assigned unit machining schedule; and

notifying an operator of the presence of said foreseeable schedule alarm condition if it is determined that said foreseeable schedule alarm condition is present.

2. A method of controlling a sheet metal machining line according to claim 1, wherein said notifying includes indicating to the operator the cause of said foreseeable alarm condition when it is determined that said foreseeable schedule alarm condition is present.

3. A method of controlling a sheet metal machining line according to claim 1, wherein said determining the presence of a foreseeable schedule alarm comprises determining whether an identification number of a machining program required to machine a workpiece is stored in the assigned unit machining schedule based on the data items of the assigned unit machining schedule.

4. A method of controlling a sheet metal machining line according to claim 1, wherein said determining the presence of a foreseeable schedule alarm comprises comparing workpiece inventory data with the data items of the assigned unit machining schedule, in order to determine if the number of available workpieces is less than the required number of workpieces for machining.

5. A method of controlling a sheet metal machining line according to claim 1, wherein said determining the presence of a foreseeable schedule alarm comprises comparing metal mold and clamp data with the data items of the assigned unit machining schedule, in order to determine if preparatory work is required.

6. A method of controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising at least one unit machining schedule, each unit machining schedule being referred to for objects to be machined and containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating a completion or non-completion of machining operations specified in the unit machining schedule, so that supplied workpieces may be sequentially machined by predetermined machining operations according to the machining schedule, said method comprising:

assigning each unit machining schedule, indicated as being non-complete by a completion code, in accordance with a predetermined order;

determining the presence of a foreseeable schedule alarm condition, that will force an operation of the sheet metal machining line to be suspended before or during the machining operation for the assigned unit machining schedule, by analyzing the data items of the assigned unit machining schedule;

determining, when a foreseeable schedule alarm condition is determined to be present, whether the assigned unit machining schedule should be skipped in accordance with a skip mode, said skip mode being provided for the operation of the assigned unit machining schedule; and

updating the data items of the assigned unit machining schedule by adding data indicating the skipping of the assigned unit machining schedule to the completion code of the assigned unit machining schedule if it is determined that said skip mode is provided.

7. A method of controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising unit machining schedules arranged in an order of machining operations to be carried out, each of said unit machining schedules containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating a completion or non-completion of machining operations specified in the unit machining schedule, so that supplied workpieces may be sequentially machined by predetermined machining operations according to the machining schedule, said method comprising:

assigning each unit machining schedule, indicated as being non-complete by a completion code, in accordance with a predetermined order;

determining the presence of a foreseeable schedule alarm condition, that will force an operation of the sheet metal machining line to be suspended before or during the machining operation for the assigned unit machining schedule, by analyzing the data items of the assigned unit machining schedule;

determining, when said foreseeable schedule alarm condition is determined to be present, whether the assigned unit machining schedule should be skipped in accordance with a skip mode, said skip mode being provided for the operation of the unit machining schedule; and

updating the data items of the assigned unit machining schedule by adding data indicating the skipping of the assigned unit machining schedule to the completion code of the assigned unit machining schedule when it is determined that said skip mode is provided;

determining if all machining operations of the unit machining schedules are complete by referring to the completion code of each unit machining schedule; and

determining, when it is determined that all machining operations of the unit machining schedules are complete, whether a retry process for retrying a skipped unit machining schedule is to be performed in accordance with a retry mode provided for the skipped unit machining schedule.

8. An apparatus for controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising a plurality of unit machining schedules arranged in an order of machining operations to be carried out, each of said unit machining schedules being referred to for objects to be machined and containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating the completion or non-completion of machining operations specified in the unit machining schedule, so that supplied workpieces may be sequentially machined by predetermined machining operations according to the machining schedule, said apparatus comprising:

assigning means for assigning each unit machining schedule, indicated as being non-complete by a completion code, in accordance with a predetermined order;

alarm condition determining means for determining the presence of a foreseeable schedule alarm condition, that will cause an operation of the sheet metal machining line to be suspended before or during the machining operation for the assigned unit machining schedule, by analyzing the data items of the assigned unit machining schedule; and

alarm condition notifying means for notifying an operator of the presence of said foreseeable schedule alarm condition when it is determined that said foreseeable alarm condition is present.

9. An apparatus for controlling a sheet metal machining line according to claim 8, wherein said alarm condition notifying means comprises a display device to notify an operator of the cause of said foreseeable schedule alarm condition when it is determined that said foreseeable schedule alarm condition is present.

10. An apparatus for controlling a sheet metal machining line according to claim 8, wherein said alarm condition determining means comprises means for determining whether an identification number of a machining program required to machine a workpiece is stored in the assigned unit machining schedule based on the data items of the assigned unit machining schedule.

11. An apparatus for controlling a sheet metal machining line according to claim 8, wherein said alarm condition determining means comprises means for comparing workpiece inventory data with the data items of the assigned unit machining schedule, in order to determine if the number of available workpieces is less than the required number of workpieces for machining.

12. An apparatus for controlling a sheet metal machining line according to claim 8, wherein said alarm condition determining means comprises means for comparing metal mold and clamp data with the data items of the assigned unit machining schedule, in order to determine if preparatory work is required.

13. An apparatus for controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising unit machining schedules arranged in an order of machining operations to be carried out, each of said unit machining schedules being referred to for objects to be machined and containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating the completion or non-completion of machining operations specified in the unit machining schedule, so that supplied workpieces may be sequentially machined by predetermined machining operations according to the machining schedule, said apparatus comprising:

assigning means for assigning each unit machining schedule, indicated as being non-complete by a completion code, in accordance with a predetermined order;

alarm condition determining means for determining the presence of a foreseeable schedule alarm condition, that will force an operation of the sheet metal machining line to be suspended before or during the machining operation for the assigned unit machining schedule, by analyzing the data items of the assigned unit machining schedule;

skip mode determining means for determining, when said alarm condition determining means determines that said foreseeable schedule alarm condition is present, whether to skip the assigned unit machining schedule in accordance with a skip mode, said skip mode being provided for an operation of the assigned unit machining schedule; and

data updating means for updating, when it is determined by said skip mode determining means that said skip mode is provided, the data items of the assigned unit machining schedule by adding data indicating the skipping of the assigned unit machining schedule to the completion code of the assigned unit machining schedule.

14. An apparatus for controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising at least one unit machining schedule, each unit machining schedule being referred to for objects to be machined and containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating the completion or non-completion of machining operations specified in each unit machining schedule, so that supplied workpieces may be sequentially machined by predetermined machining operations according to the machining schedule, said apparatus comprising:

assigning means for assigning each unit machining schedule, indicated as being non-complete by a completion code, in accordance with a predetermined order;

alarm condition determining means for determining the presence of a foreseeable schedule alarm condition, that will force an operation of the sheet metal machining line to be suspended before or during the machining operation for the assigned the assigned unit machining schedule, by analyzing the data items of the assigned unit machining schedule;

skip mode determining means for determining, when said foreseeable schedule alarm condition is determined to be present by said alarm condition determining means, whether to skip the assigned unit machining schedule in accordance with a skip mode, said skip mode being provided for an operation of the assigned unit machining schedule;

data updating means for updating, when it is determined by said skip mode determining means that a skip mode is provided, the data items of the assigned unit machining schedule by adding data for skipping the assigned unit machining schedule to the completion code of the assigned unit machining schedule;

completion determining means for determining if all the machining operations of the machining schedule are complete by referring to the completion code of each unit machining schedule; and

retry process determining means for determining, when it is determined by said completion determining means that all of the machining operations are complete, if a retry process for retrying a skipped unit machining schedule is to be performed in accordance with a retry mode provided for the skipped unit machining schedule.

15. An apparatus for controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising machining records arranged in an order of machining operations to be carried out, each of said machining records being referred to for objects to be machined and containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating the completion or non-completion of machining operations specified in each machining record, such that workpieces may be sequentially machined according to the machining schedule, said apparatus comprising:

an assigning system which assigns each machining record, indicated as being non-complete by a completion code, in accordance with a predetermined order;

an alarm condition determining system which determines the presence of a foreseeable schedule alarm condition that will force an operation of the sheet metal machining line to be suspended before or during the machining operation for the assigned machining record, said alarm condition determining system determining said foreseeable schedule alarm condition by analyzing the data items of the assigned machining record; and

an alarm condition notification system which notifies an operator of said foreseeable schedule alarm condition when said alarm condition determining system determines the presence of said foreseeable schedule alarm condition.

16. An apparatus for controlling a sheet metal machining line according to claim 15, wherein said alarm condition notification system notifies an operator of a cause of said foreseeable schedule alarm condition.

17. An apparatus for controlling a sheet metal machining line according to claim 15, wherein said alarm condition determining system comprises means for determining whether an identification number of a machining program required to machine a workpiece is stored in the assigned machining record based on the data items of the assigned machining record.

18. An apparatus for controlling a sheet metal machining line according to claim 15, wherein said alarm condition determining system comprises means for comparing workpiece inventory data with the data items of the assigned machining record, in order to determine if the number of available workpieces is less than the required number of workpieces for machining.

19. An apparatus for controlling a sheet metal machining line according to claim 15, wherein said alarm condition determining system comprises means for comparing metal mold and clamp data with the data items of the assigned machining record, in order to determine if preparatory work is required.

20. An apparatus for controlling a sheet metal machining line in accordance with a machining schedule, said machining schedule comprising a plurality of machining records arranged in an order of machining operations to be carried out, each of said machining records being referred to for objects to be machined and containing data items including identification numbers of machining programs, a number of workpieces to be machined, a presence or absence of preparatory work to be performed, and a completion code for indicating the completion or non-completion of machining operations specified in each machining record, such that workpieces may be sequentially machined according to said at least one machining record, said apparatus comprising:

an assigning system which assigns each machining record, indicated as being non-complete by a completion code, in accordance with a predetermined order;

an alarm condition determining system which determines, prior to performing the machining operations of the assigned machining record, the presence of a foreseeable schedule alarm condition that will cause an operation of the sheet metal machining line to be suspended before or during the machining operations for the assigned machining record, said alarm condition determining system determining said foreseeable schedule alarm condition by analyzing the data items of the assigned machining record;

a skip mode determining system which determines, if said foreseeable schedule alarm condition is determined to be present by said alarm condition determining system, whether to skip an assigned machining record in accordance with a skip mode, said skip mode being provided for a machining operation of the assigned machining record; and

a data updating system which updates, when it is determined by said skip mode determining system that said skip mode is provided, the data items of the assigned machining record by adding data indicating the skipping of the assigned machining record to the completion code of the assigned machining record.

21. An apparatus for controlling a sheet metal machining line according to claim 20, further comprising:

a completion determining system which determines if all machining operations of the machining records are complete by referring to the completion code of each of the machining records; and

a retry process determining system which retries a skipped machining record in accordance with a retry mode provided for the skipped machining record if it is determined by said completion determining system that all machining operations are complete.