Patent ID: 7092775

Claim:
A production planning apparatus for devising a production plan based on at least shipping plan information and parts table of a product, the production planning apparatus comprising: a calculation processing portion; a storage portion; and input/output means, wherein the production planning apparatus divides a production step of the product into multiple production steps based on a constraint to be considered when a production plan therefor is devised, defines identifiers for the multiple production steps and prestores the defined identifiers in the storage portion as step identification information, and stores step information having at least correspondences between the production steps and items in the storage portion; wherein the production planning apparatus stores, in the storage portion, setup time information indicating the setup share for each work schedule in each production step; the calculation processing portion has: a first calculation processing portion for calculating a date to start, date to complete and amount to complete of an item by using shipping plan information, a parts table, inventory information and warehousing schedule information, based on a first calculation algorithm; a second calculation processing portion for calculating a date and time to start, date and time to complete and amount to complete of an item by using shipping plan information, step information and setup time information, based on a second calculation algorithm; and a calculation control portion for controlling the first and second calculation processing portions; and the calculation control portion identifies and determines production steps and order of calculations, which are involved in the production of the product, based on the shipping plan information, parts table and step information and activates and controls one of the first and second calculation processing portion based on the step identification information or the value of the setup time information if the step identification information is not available, to calculate a production plan for each production step based on the order of calculations.