Dynamometers have been a part of performance measurement since the days when the presence of horsepower was usually accompanied by four hooves and a tail. This versatile tool is applied around the world, as companies like Taylor Dynamometer build on past innovations with new breakthroughs in data gathering and system control technology.

• 1828 Gaspard de Prony invented the de Prony Brake, one of the earliest dynamometers
• 1838 Charles Babbage, known to historians as the Father of the Computer, introduces a dynamometer car to measure the pulling power of English railroad locomotives
• 1877 William Froude of Great Britain invents the first hydraulic dynamometer, with the first commercial models produced in 1881
• 1921 Professor E.V. Collins of Iowa State College develops a draft horse dynamometer, used to measure a horse’s capability to pull the era’s heavy metal farm implements
• 1930 Using designs pioneered through a collaboration with Rudolph Diesel, John Taylor forms the Taylor Dynamometer and Machine Company to produce engine dynamometers
• 1931 Martin and Anthony Winther introduce the first eddy current dynamometer

Throughout the past seven decades of continued dynamometer development, Taylor has maintained its status as a leader in advancing power measurement technology. Contact us to learn about the latest developments in dynamometers and engine diagnostics, or to inquire about a specific dyno product or application.

How Dynamometers Work

All dynamometers perform the same essential function, measuring the torque, rotational speed and power output of a combustion engine, electric motor or other power source. While the outcome is the same, many technologies are used to achieve the desired result.

Two Main Types

Most dynamometers can be placed within two distinct categories. Engine dynamometers are designed for coupling directly to the driveshaft of an engine under test, and chassis dynamometers measure the power output of a drive train by using rollers turned by the tires of a vehicle under test. In addition to the two traditional types, Taylor offers a line of portable dynamometers that attach directly to the flywheel of an engine. This allows accurate measurement of engine output without removal of an engine from its drive train.

A Variety of Designs

The work of handling and measuring input power is performed by instruments with a variety of different designs:

o Eddy current dynamometers present a measurable resistant force to engines under test by harnessing the magnetic flux between fixed and rotating electromagnets spun by the engine under test.

o A variant of the eddy current design, powder dynamometers create flux through the application of a fine magnetic powder between the rotor and coil

o Electric motor/generator types are a variation on the adjustable speed drive, using solid state components rather than the physical relationship between electromagnets to create measurable power transfer

o Fan, hydraulic and water brakes use air, water or hydraulic fluid to deliver physical resistance to the power applied by an engine or motor under test. The amount of resulting force absorbed by the fluid is measured to provide an indication of the power applied to the system

The best resource for details on dynamometer function and application is a Taylor Dynamometer application specialist. Contact us for full details on putting the latest in dynamometer technology to work in your application.

Eddy Current Dynamometer History

The story of the eddy current dynamometer is a tale of two Danish boys from Wisconsin, growing up in a time when innovations required an inquiring mind and a machine shop rather than a supercomputer and a doctoral degree. Martin Phillip Winther arrived at Ellis Island, New York in 1892 from his native Denmark. The family ultimately settled in Kenosha Wisconsin, where Martin and his American-born brother Anthony began their working lives as laborers at the Jeffry Company, makers of the Rambler automobile. At Jeffry, the brothers were involved in the engineering of a four-wheel-drive truck, which led them to break away and found the Winther Motor and Truck Company in 1917. While Winther Motor and Truck made several types of motor vehicles (including light trucks, fire engines and a sporty automobile) the firm’s chief product was innovation. Beginning around 1920, Martin and Anthony Winther were granted patents for almost 300 mechanical devices. These included the first successful air conditioning system for Pullman railroad cars, a four-wheel-drive post hole digger for AT&T, the first induction coupling, a magnetic clutch, a cycle-car, variable-speed transmission gears, as well as a giant press drive, brakes and couplings for the oil field industry.

Although prolific, only one of the Winther brothers’ inventions proved to have lasting impact. They are chiefly known for the invention of the eddy current dynamometer, a type of high speed, high power dynamometer capable of far surpassing the products then available in terms of power handling capability. The eddy current dyno was able to turn fast enough to test the turbine engines used in aircraft, wind tunnels and high speed automobiles of the day. The eddy current dynamometer was the chief product of the Dynamatic Corporation, founded by the Winthers in 1932. The firm was successful for many years both before and after the brothers sold their interest to Eaton Corporation in 1946. Variations on the eddy current design still serve as the basis for dynamometers today. The designs continued use is a testament to the ingenuity of two men who never rose above the eighth grade in formal education, yet parlayed their considerable on-the-job insight into a lasting legacy of technical achievement.