Self-calibrating machines for balancing work pieces and methods of machine calibration

In this system an unbalancing force, as set by an unbalance load injection device integrated into a work piece balancing machine and its balance computer, is injected into an injection planethrough an operating portion of the machine. This injected load is in effect transferred by computation to a calibrating plane of a known standard or a masterwork part loaded into and rotatably driven by the balancing machine. The values of the unbalancing force as generated by the unbalance injecting device and by calculation into the rotating master are sensed by synchronizer and vibration pick-ups. Data reflective of the injected imbalance are furnished to the balance computer for the calibration thereof. The principle of this self-calibration is to use a workpiece drive spindle and unbalance injector device that can introduce a known unbalance, set by adjusting the unbalance injector device to inject a predetermined load at a known angle into the master to effect master unbalance. This induced unbalance is picked up by synchronizer units and used as the parameters in the calibration process of the balance compute. This allows the machine to accurately determining the imbalance in other work pieces. Subsequently conventional unbalanced work parts processed by the calibrated machine can be balanced by the machine with a higher-level of accuracy in accordance with balancing data of the calibrated balance computer.