Controller of conveyance system

• US 5,867,388 A
• Filed: 03/18/1996
• Issued: 02/02/1999
• Est. Priority Date: 03/17/1995
• Status: Expired due to Term

• Current Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Original Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Inventors: Kuroyanagi, Masaaki, Taki, Takafumi, Okumura, Toshihiro
• Primary Examiner(s): Trammell, James P.
• Assistant Examiner(s): Bui, Bryan
• Application Number:
  US08/617,168
• Time in Patent Office: 1,051 Days
• Field of Search: 364/468.17-468.22, 364/228.1, 364/228.3-238.4, 364/130-132, 364/551.01, 364/552, 364/478.01, 364/478.02, 364/478.05 , 364/478.07, 364/478.16, 364/478.18, 395/200.31, 395/427, 395/200.3, 414/786
• US Class Current: 700/112
• CPC Class Codes: B65G 1/00 Storing articles, individually or in orderly arrangement, in warehouses or magazines conveyor combinations in warehouses, magazines or workshops B65G37/00; stacking of articles B65G57/00; removing articles from stacks B65G59/00; loading machines B65G65/02
• CPC Class Codes: G05B 19/41865 characterised by job scheduling, process planning, material flow
• CPC Class Codes: G05B 19/4189 characterised by the transport system
• CPC Class Codes: G05B 2219/31 From computer integrated manufacturing till monitoring
• CPC Class Codes: G05B 2219/32 Operator till task planning
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass

Abstract

A controller of a conveyance system efficiently conveys parts. The controller includes an input/output interface receiving data related to the position and loading state of data of each vehicle; receiving carry-in/out requests from each job shop; and outputting carry-in/out instructions to each vehicle. The controller also includes a ROM storing a control program; a RAM storing job shop positional data, carry-in/out requests, vehicle loading state data; and a processing section computing values of a carriage instruction (e.g., origin, destination, carrier to be carried, carrying route) given to each vehicle using the carry-in/out request data from each job shop and the data stored in the RAM based on the program stored in the ROM.

Claims

1. A controller of a conveyance system connected to a production line having a plurality of independent work stations for implementing a certain processing to parts, a distribution station for temporarily holding said parts, a plurality of passes provided and set in advance between said work stations and said distribution station, and a plurality of carrier means for carrying said parts to any one of said work stations and said distribution station by moving through the passes, said controller performing centralized control over the conveyance of said parts using said carrier means, said controller comprising:

request storage means for storing a carry-in request of said parts either from any one of said work stations or said distribution station to any other of said work stations and a carry-out request of said parts either from any one of said work stations to any other of said work stations or said distribution station in order of generation of the requests;

request selecting means for selecting requests in order of storage up to a maximum loading capacity of said parts on said carrier means from requests stored in said requests storage means;

computing means for specifying a work station/distribution station to/from which said parts should be carried in/out based on each selected request; and

carriage control means for determining, responsive to said computing means, a carrying route of said carrier means and outputting a carriage instruction to said carrier means so that said carrier means performs carry-in or carry-out operations in accordance with each request selected by said request selecting means every time said carrier means arrives at one of said work stations or said distribution station following the carrying route.

2. A controller according to claim 1, wherein said carriage control means is for outputting a carriage instruction always instructing said carrier means to carry in and carry out said parts sequentially at the same work station when carriage works following said carry-in request are required to be done at the same station.

3. A controller according to claim 1, wherein said request selecting means is for setting a type of request which is generated more among said carry-in requests and said carry-out requests stored in said request storage means as a first request type, is for selecting requests of the first request type as much as possible up to the maximum loading capacity of said parts of said carrier means in order of storage and also is for selecting a request of a second request type, which is different from said first request type, when it is stored in said request storage means, the request of the second request type being made by any one of said work stations or said distribution station.

4. A controller according to claim 1, wherein said request selecting means is for selecting requests in order of storage as much as possible up to the maximum loading capacity of said parts of said carrier means from requests stored in said request storage means and also is for selecting requests whose carry-in/out condition is different when requests having different carry-in/out conditions with respect to each of said selected requests are stored in said request storage means, the request of the second request type being made by any one of said work stations or said distribution station.

5. A controller according to claim 4, wherein said request selecting means is for selecting requests whose carry-in/out condition is different when the requests having the different carry-in/out condition with respect to each of said selected requests are stored in said request storage means related to each selected request every time when one request is selected in order of the storage in said request storage means as much as possible up to the maximum loading capacity of said parts of said carrier means.

6. A controller according to claim 1, wherein said request selecting means is for counting said carry-in/out requests stored in said request storage means for said work stations, is for selecting requests as much as possible up to the maximum loading capacity of said parts of said carrier means in order from a work station having the most requests, and also is for selecting requests whose carry-in/out condition is different when a request having a different carry-in/out condition with respect to each of said selected requests are stored in said request storage means, the request of the second request type being made by any one of said work stations or said distribution station.

7. A controller according to claim 1, wherein said request selecting means is for selecting requests as much as possible up to the maximum loading capacity of said parts of said carrier means based on a priority intrinsic to said parts from each request stored in said request storage means and also is for selecting requests whose carry-in/out condition with respect to each of said selected requests are stored in said request storage means, the request of the second request type being made by any one of said work stations or said distribution station.

8. A controller according to claim 1, wherein said request selecting means is for selecting requests as much as possible up to the maximum loading capacity of said parts of said carrier means in order from one having a shorter pass for conveying said parts from each request stored in said request storage means and also is for selecting requests whose carry-in/out condition is different when the request having the different carry-in/out condition with respect to each of said selected requests are stored in said request storage means, the request of the second request type being made by any one of said work stations or said distribution station.

9. A controller according to claim 1, wherein said carriage control means is for outputting a carriage instruction instructing said carrier means to carry out parts after carrying in said parts to the same work station when carriage works following said carry-in request and said carry-out request are required to be done at the same work station.

10. A controller according to claim 1, wherein said carrier means is for confirming that there is a space in said work station which has made a carry-in request to which parts can be carried in and then carrying said parts to said space.

11. A controller according to claim 1, wherein said carriage control means is for outputting a carriage instruction so that the same area is used for parts to be carried in and for parts to be carried out in said carrier means when carriage work is required to be done following said carry-in request and said carry-out request the same station.