Corliss’s Patent Model of a Steam Engine – ca 1849
date: label: date made
content: 1849
label: patent date
content: 1849-03-10
name: label: inventor
content: Corliss, George H.
notes: label: Description
content: This model was filed with the application to the U.S. Patent Office for Patent Number 6,162 issued to George H. Corliss of Providence, Rhode Island on March 10, 1849, and reissued May 18, 1851. This is considered the first variable cut-off valve gear in which the point of the cut-off is determined by the engine governor. The patent was the first issued to George H. Corliss for steam engine improvements, and the model represents the original form of the Corliss steam engine.
label: Description
content: The patent is based on a walking beam steam engine, and the wooden patent model shown in the image represents the major features of such an engine. The crankshaft is at the left with the steam cylinder at the right. A small fly-ball governor can be seen to the left of the central column of the model. Steam inlet and exhaust valves are located at the top and bottom of the cylinder. The control rods for the upper set of valves are visible at the top left of the cylinder.
label: Description
content: The main feature of Corliss’ patent dealt with the operation and timing of the steam inlet valves. He provided a method for the governor to change the timing at which the high pressure steam was cut off during the stroke of the piston. If the engine speed increased beyond the desired speed, the movement of the governor caused a set of geared racks to disengage the control rods so as to close the inlet valves earlier. This caused the speed to decrease as engine power was reduced.
label: Description
content: Corliss was a prolific inventor of steam technology in the middle 1800s and was the founder of the Corliss Steam Engine Company. His engines were used worldwide, and his designs were adopted by other engine manufacturers.
label: Description
content: The patent model is constructed of wood with some metal parts. All of the key elements of the patent are illustrated by the model including the governor, the steam valves and their operating mechanisms. Diagrams showing the complete design of the patent can be found in the patent document online at the United States Patent and Trademark Office website, www.uspto.gov.
place: label: place made
content: United States: Rhode Island, Providence
label: associated place
content: United States: Rhode Island, Providence
topic: label: Subject
content: Patent Models
label: Subject
content: Steam Engines
setName: label: See more items in
content: Work and Industry: Mechanical and Civil Engineering
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content: Engineering, Building, and Architecture
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content: Patent Models
label: Exhibition
content: Power Machinery
label: Exhibition Location
content: National Museum of American History
publisher: label: Related Publication
content: Frank A. Taylor. Catalog of the Mechanical Collections of the Division of Engineering United States National Museum, Bulletin 173
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MC.308646
label: catalog number
content: 308646
label: accession number
content: 89797
label: patent number
content: 6,162
objectType: label: Object Name
content: engine, steam. model
label: Object Name
content: engine, steam. patent model
label: Object Name
content: patent model, engine, steam
physicalDescription: label: Physical Description
content: wood (overall material)
label: Measurements
content: overall: 22 in x 24 in x 6 in; 55.88 cm x 60.96 cm x 15.24 cm