Page:The Kinematics of Machinery.djvu/289

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COMPOUND WHEEL TRAIN.

267

Starting from the turning pair 2 we have, on each side, simply a pair of spur-wheels with their connecting link. We write them singly and add them together as follows :

2 b, a I 2

c+ ...

... C\

><?t ...

... (C) ... |

| ... C-

2

c,

3

2

2 C+ ...

b,

\ Rj

a,

1

... (C)^} i t f*i\ \

..ii Iff-

I ,

c, <f

i ... (6)...) 3

This shows two binary links a, 1 and d, 3, and two ternary links, 2, 5, c and 2, 1, 3. The latter are the coupled wheels b and c with

FIG. 187.

their common spindle, and the bar with the bearings, which as the underlining shows, is fixed.

We may obtain the formula in another shape as follows. Begin- ning with the wheel a and its spindle, we then write the wheel b and its connections at once as a ternary link ; continue with d, and write its linkage with 3 ; and then unite the second cylinders of 2 and of 3 with 1. For distinctness' sake we use the uncontracted form.

1 a, I 2 I

C+

c,d