The Merrill Wheel-Balancing System was the world's first electronic dynamic
wheel-balancing
Tire balance, also called tire unbalance or tire imbalance, describes the distribution of mass within an automobile tire or the entire wheel (including the rim) on which it is mounted.
When the wheel rotates, asymmetries in its mass distribution ...
system. It was invented in 1945 by Marcellus Merrill at the Merrill Engineering Laboratories, 2390 South Tejon Street,
Englewood, Colorado
The City of Englewood is a home rule municipality located in Arapahoe County, Colorado, United States. The town population was 33,659 at the 2020 United States Census. Englewood is a part of the Denver–Aurora–Lakewood, CO Metropolitan Stati ...
, and is now recorded on the
list of IEEE Milestones in
electronic engineering[{{cite web , url=http://www.ieeeghn.org/wiki/index.php/Milestones:Merrill_Wheel-Balancing_System,_1945 , title=Milestones:Merrill Wheel-Balancing System, 1945 , author= , date= , work=IEEE Global History Network , publisher=IEEE , accessdate=3 August 2011] and as an
American Society of Mechanical Engineers
The American Society of Mechanical Engineers (ASME) is an American professional association that, in its own words, "promotes the art, science, and practice of multidisciplinary engineering and allied sciences around the globe" via "continuing ...
landmark.
Before Merrill's invention, all wheel-balancing for automobiles, trucks, etc., required removal of the wheel from the vehicle. Most required some form of static balancing without wheel rotation, which was slow and error-prone.
Merrill's invention balanced wheels while still mounted to the vehicle, by spinning them at high speed and electronically analyzing the vibrations to trigger a
stroboscope. Technicians could then determine where balancing weights should be added.
References
ASME Landmarks
Automotive technologies