Watt's Engine
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video simulation file.
Software copyright © 2004 by The McGraw-Hill Companies, Inc. All rights reserved.
Info
In 1784, James Watt designed this steam engine to produce power directly on a shaft (in gray). At the time there were no means available for machining crosshead guides that would accurately constrain the piston to move in a straight line. The ingenious Watt's linkage is a straight line mechanism developed to circumvent this difficulty. The double acting cylinder has a bore diameter of 19 inches with a 4 ft stroke. With the output link and gears included, the six-bar linkage is categorized as the Watt's six-bar linkage. Note that the sun gear and planet (in pink) gears have the same size.
Source
This Working Model file is adapted from Figure P2-10 on p. 80 in Design of Machinery, 3rd ed. by Norton, R.L., McGraw-Hill, 2004.
It is also from Figure 3.34-18 on
p. 15 in Kinematics and
Dynamics of Planar Machinery by Paul, B.
K., Prentice-Hall, 1979,
and from Figure 1-9 on p. 101 in Kinematic
Synthesis of Linkages by Hartenberg,
R.S. and Denavit., McGraw-Hill, 1964, and from Figure 2.5 on p. 29
in The
Innovators-The Engineering Pioneers Who Made America Modern, by
Billington, D.P., John Wiley & Sons, Inc., 1996.
Credits
This Working Model file was first developed by Fan (Michael) Mo.