The Hard Bearing Principle

Pro-bal's "hard bearing" system of measuring unbalance, transducers are used to directly measure the unbalance force. When parts rotate on our equipment, the centrifugal force, due to the unbalance, tends to move the bearing fixture assembly forward and backward. This motion is detected by the transducer which directly measures the centrifugal force.

There is no perceptible motion of the bearing fixture and this stationary measuring system is, therefore, not dependent upon rotor mass or inertia. This makes it possible to calibrate the machine for a variety of parts unlike a "soft bearing" machine which has to be calibrated with each change in type and size of part.