CATALOG OF THE MECHANICAL COLLECTIONS g5 



THOMPSON AND HUNT SHAFT GOVERNOR, 1878 



Plate 19, Figure 2 



U.S.N.M. no. 308700 ; original patent model ; transferred from the United States 

 Patent Office ; photograph no. 32799. 



This model was submitted with the application for the patent is- 

 sued to Joseph W. Thompson and Nathan Hunt, of Salem, Ohio, 

 June 18, 1878, no 204924. One-half of tlie inventors' right was as- 

 signed to the Buckeye Engine Co., of the same place. 



The model represents a centrifugal governor in which weights ro- 

 tate with and upon the driving shaft and operate by variation of 

 annular velocity to vary the position of an eccentric thereon, relative 

 to the crank. The peculiar features of this governor are the use 

 of ball-and-socket joints to connect the weighted arms to the eccentric 

 and the provision of stop pins moving in cushioned slots to prevent 

 shock due to sudden changes in speed while permitting the engine to 

 be run in either direction. 



The inventors refer to former shaft governors as having been pat- 

 ented by Jacob D. Custer, no 1179, June 21, 1839, and by Joseph W. 

 Thompson, no. 162715, April 27, 1875. The invention of the shaft 

 governor has heretofore been generally attributed to J. C. Hoadley. 



The Buckeye engine, which has been a representative and success- 

 ful type of high-speed, automatic engine, was developed mainly under 

 the patents of J. W. Thompson and Nathan Hunt. The peculiar type 

 of shaft governor and the balanced flat valve (see above) were the 

 characteristics of the engine. 



REID GYROSCOPIC ENGINE GOVERNOR, 1879 



U.S.N.M. no. 309242 ; original patent model ; transferred from the United States 

 Patent OflBce; not illustrated. 



This model was submitted with the application for the patent issued 

 to Joseph Keid, Monroe, La., October 21, 1879, no. 220867. 



This model represents a hollow vertical spindle geared to be driven 

 by the engine. Pivoted at the top of the spindle is a gyroscopic 

 wheel, which ordinarily rests at an inclination to the spindle but when 

 rotated is acted upon by gyroscopic and centrifugal forces tending to 

 swing the axis of the wheel to the vertical. The changes in position of 

 the wheel follow changes in velocity of the wheel, so that by suitable 

 connections of the axis of the wheel to a governor valve the device 

 will control the speed of the engine to which it is attached. 



PICKERING BALL GOVERNOR, OLD STYLE 

 U.S.N.M. no. 310289 ; original ; gift of the Pickering Governor Co. ; not illustrated. 



In this governor each ball is supported at the center of a vertical, 

 flat, laminated spring, so arranged that as the balls move away from 

 the spindle of the governor, owing to centrifugal force, and cause the 



