Knowles Steam Pump, Patent Model

This model was filed with the application to the U.S. Patent Office for the patent issued to Lucius J. Knowles, of Worcester, Massachusetts, April 1, 1879, no. 231823.
The model represents the steam cylinders of a duplex pump fitted with what the inventor calls auxiliary engines to operate the valves of each cylinder when it is desired to use one cylinder of a duplex pump without the other. Actually the piston of the auxiliary engine is the valve of the main cylinder and the invention is in effect a one cylinder “simplex” pump with steam-actuated valve. This is one of the earliest uses of the steam-actuated valve for steam pumps.
The auxiliary cylinder forms the steam chest and valve ports of the main cylinder while the auxiliary piston acts as the valve. The auxiliary piston has its own valve system, which consists of ports in the auxiliary cylinder wall connected to the main steam passages and so located that they will register with openings in the auxiliary piston when the auxiliary piston is given a slight twist at the end of the main piston’s stroke. These openings connect to passages in the auxiliary cylinder to cause the auxiliary piston to move to the other end of the cylinder and so reverse the stroke of the main piston.
Lucius James Knowles (July 2, 1819 – February 26, 1884) originated and developed the Knowles Steam Pump Co. and the L. J. Knowles & Brother Loom Works at Warren, Massachusetts, and Worcester, Massachusetts, both of which became leading organizations in their respective fields. The Knowles steam pump was one of the best known of the direct-acting pumps, and Knowles is recognized as having contributed much to the final development and refinement of the device. He was one of the first to take up and develop the steam-actuated valve and received several patents for his inventions of improvements in valves.
This description comes from the 1939 Catalog of the Mechanical Collections of the Division of Engineering United States Museum Bulletin 173 by Frank A. Taylor.
Currently not on view
date made
patent date
Knowles, Lucius J.
place made
United States: Massachusetts
associated place
United States: Massachusetts, Worcester
overall-from catalog card: 12 in x 12 in; 30.48 cm x 30.48 cm
overall: 9 3/4 in x 12 1/4 in x 10 in; 24.765 cm x 31.115 cm x 25.4 cm
ID Number
accession number
patent number
catalog number
See more items in
Work and Industry: Mechanical and Civil Engineering
Industry & Manufacturing
Bulletin 173
Engineering, Building, and Architecture
Data Source
National Museum of American History


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