How Wheel Balancers Work

The computer within the balancer receives the premeasured values of wheel dimensions and responds to the output of a rotational speed sensor that monitors the rotational speed of the shaft. When the required speed is reached, the mechanical system automatically decouples the powered cranking shaft from the wheel shaft so that there can be no externally applied disturbances for the subsequent measurements of imbalance. Multiple spaced transducers along the shaft determine the wheel run-out attributable to imbalances in both the inner and outer wheel rim planes and the computer provides output signals indicative of the correct balance weight and the mounting positions of the weights on the wheel rim.