[Nos. 145-160] Steam Power Group, Engines, Turbines
Double Quadrant Steam Engine
William M Clark
38.7cm x 38.7cm
Cast aluminum and wood (painted) on a vertical panel.
For educational use only. All rights reserved by the contributor(s) and publisher(s).
four-bar linkage, steam engine
This model is called the double quadrant steam engine because the two piston rods are attached to arms, which move in a quadrant or area equal to one quarter of a circle. Steam enters from the boiler at the top. The inlet valve A is attached to crank B on under side by a cam. Valve A allows steam to enter steam ports moving each piston arm alternately in a quadrant, turning crank B. On return stroke of red arms steam escapes into interior chamber C and through exhaust port into the air.
[Virginia Downward & William M. Clark, 1930]
[Editorís Note: This engine consists of two four-bar linkages that are acted upon by steam that enters in the right and left chambers. Clark copied this model from Figure 423 of the 1868 catalog of mechanical movements by Henry T. Brown. According to Brown, the engine was patented by Root. This model illustrates the variety of engine topologies that were explored in the 19th century. FCM]