Operation monitoring device for monitoring operations of machining devices in machining line

An operation monitoring device which monitors operations of a plurality of machining devices in a machining line comprising the machining devices and at least one workpiece stocker configured to temporarily store workpieces machined by the machining devices, the operation monitoring device comprising:

• a workpiece stocker management information storage unit configured to store a current stock number indicative of the number of workpieces currently stocked in each workpiece stocker;
• an operation information acquisition unit configured to acquire information on a state of the workpiece stocker constituting the machining line;
• a stock number updating unit configured to update the current stock number for the workpiece stocker stored in the workpiece stocker management information storage unit, based on the information on the state of the workpiece stocker acquired by the operation information acquisition unit;
• a stock number determination unit configured to determine the necessity of change of machining speeds of the machining devices constituting the machining line, based on the current stock number for the workpiece stocker stored in the workpiece stocker management information storage unit;
• and
• a machining speed change command unit configured to command the machining devices located before the workpiece stocker in the machining line and/or the machining devices located behind the workpiece stocker to change the machining speeds thereof if the stock number determination unit determines that the change of the machining speeds is necessary.