1. Field of the Invention
The present invention relates to a production system that is configured by disposing, downstream of a supply device for supplying foodstuffs or other such articles, a plurality of constituent devices including a weighing machine for weighing articles, a packaging machine, and a seal checker or another such quality inspection device.
2. Background Information
In conventional practice, production systems in use include a weighing unit for weighing foodstuffs or other such articles supplied from a supply unit, a packaging unit for packaging the weighed articles, a quality inspection unit for detecting the quality of the packaged articles, and other various devices.
For example, Japanese Laid-Open Patent Application No. 9301327 (published Nov. 25, 1997) discloses a management method and a management device (production system) for a production line that varies the set capacities of certain devices according to the processing capacities (yield rate) of other devices disposed downstream when operation is initiated or during operation. Since the set capacities of these devices are varied on the basis of the processing capacities (yield rate) of the other devices, the yield rate of the entire production line can be improved, and higher capacities can be elicited from the devices to improve production efficiency.
However, this conventional production system has the following problems.
Specifically, in the production system disclosed in the aforementioned publication, the set capacities are varied on the basis of the processing capacities (yield rate) of the devices, making it impossible to deal with problems such as a lack of uniformity in the rates at which articles are fed from the supply unit in the weighing unit during operation and halted operation of one weighing unit in a plurality of weighing units.
For example, when articles are supplied from the supply unit at non-uniform rates while the set capacities of the supply unit for supplying articles to the weighing unit are kept constant, the set capacity of the weighing unit is set in accordance with the setting of the supply unit. Therefore, fluctuations in the supply rates cannot be appropriately dealt with merely by performing control based on the processing capacities or the yield rates of the devices, and production cannot be carried out efficiently.
When the operation of a single weighing unit among a plurality of weighing units is halted due to a malfunction, a control procedure is performed to increase the set capacities of the other weighing units because the operating rate of the single weighing unit is zero. However, in such cases as well, merely allocating a processing rate that is proportionate to the operating rate reduction to the other weighing units brings the operating rate of the other weighing units closer to the maximum set capacities, and may instead result in a lower yield rate and reduced production quantities.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved production system in which high production efficiency can be maintained in the entire production line, even in cases in which the articles are actually supplied from the supply unit at non-uniform rates, some of the weighing units, packaging units, quality inspection units, and other constituent units stop operating, and/or other problems occur. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.