Ratchet and Pawl
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video simulation file.
Software copyright © 2004 by The McGraw-Hill Companies, Inc. All rights reserved.
Info
As the pawl lever (in purple) with the driving pawl (in green) is made to oscillate, the ratchet wheel (in blue) will rotate counterclockwise with an intermittent motion. A holding pawl (in orange) prevents the ratchet wheel from rotating backward when the pawl lever is rotated clockwise in preparation for another stroke. This mechanism has many applications, particularly in counting devices.
Source
This Working Model file is adapted from Figure 2-12(b) on p.45 in Design of Machinery, 3rd ed. by Norton, R.L., McGraw-Hill, 2004, and also from a figure on p.444 in Mechanisms & Mechanical Devices Sourcebook, by Chironis, N.P., McGraw-Hill, 1991.
It is also adapted from Figure 3-33 on p. 64 in Kinematics and Dynamics of Machines, 2nd ed. by Martin, G.H., McGraw-Hill, 1982, and also from Figure 2.36 on p. 52 in Mechanisms and Dynamics of Machinery, 4th ed. by Mabie, H.H and Reinholtz, C.F., John Wiley & Sons, 1987.
Credits
This Working Model file was first developed by Fan (Michael) Mo.