Page:The Kinematics of Machinery.djvu/328

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KINEMATICS OF MACHINERY.

If we expand the pin 2 instead of 1, and make it large enough to include 1 within its profile, we obtain the form of chain shown in Fig. 233. If this be placed on d and driven by a, we have the mechanism GF-*-)* in the form which is so familiar to us as an

FIG. 233.

eccentric and rod. It can be seen at once that it differs only in its constructive form from the common slider-crank. This expan- sion is also used in practice placed on a, so as to give us the turn- ing block slider-crank, (C ff s P-^ . Fig. 234 shows a form in which

FIG. 234.

Mr. Whitworth * has thus applied it, where b being the driving

link its special formula becomes (C'^P- 1 -^ ; it is here used as a quick-return motion, and has already been described and named by Eedtenbacher.f The driving rod and parts connected with it do

t Die Beweyunys-Mechanismen (Basserman).
 * See Prof. Shelley's Workshop Appliances, p. 253.