Judson and Cogswell Governor, Patent Model

This model was submitted to the U.S. Patent Office with the application for the patent issued to Junius Judson and William A. Cogswell, of Rochester, New York, November 9, 1875, no. 169815.
The model represents a flyball governor in which the driving pulley is fitted loosely to the driving shaft and connected to it by a spiral spring, which allows a free turning of the pulley on the shaft to an extent sufficient to counteract the jerks or impulses, which are transmitted to the governor by the uneven operation of the engine.
The inventor states that the ordinary crank motion of a steam engine results in an unequal operation that is not always equalized by the flywheel of the engine. This irregularity, though not always perceptible, is transmitted to the governor, which, when operated unevenly, would exaggerate the variations. This device is designed to prevent the jerks being transmitted to the governor.
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
Object Name
governor, steam engine, model
patent model, governor, steam
date made
patent date
Judson, Junius
Cogswell, William A.
overall-from catalog card: 15 in x 18 1/4 in; 38.1 cm x 46.355 cm
overall: 18 3/4 in x 15 in x 11 1/2 in; 47.625 cm x 38.1 cm x 29.21 cm
place made
United States: New York, New York
associated place
United States: New York, Rochester
ID Number
catalog number
accession number
patent number
Engineering, Building, and Architecture
Industry & Manufacturing
Bulletin 173
See more items in
Work and Industry: Mechanical and Civil Engineering
Bulletin 173
Data Source
National Museum of American History, Kenneth E. Behring Center
Related Publication
Frank A. Taylor. Catalog of the Mechanical Collections of the Division of Engineering United States National Museum, Bulletin 173

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Enter the characters shown in the image.