Page:The Kinematics of Machinery.djvu/599

 STEERING GEAR.

�577

�shown in Fig. 435, of which the contracted formula, beginning with 1, is (C^P^C'IC^). If it be placed upon a it gives a planet- wheel train with a straight slider, a combination which has found numerous applications.

We obtain a special form of this by making d an annular wheel as in Fig. 436. In this form the chain, without recognition of its nature, has recently found several applications. Among others it has been used in an arrangement of steering-gear by Caird and Kobertson.* They place the chain on a and use e as the driving- link, formula (C^P^C-^. The diametral ratio of the wheels is made very nearly equal to unity, so that the rudder moving

���FIG. 437.

�FIG. 438.

�slowly is well under control. The rudder shaft is conaxial with d. With the wheel as the driving-link this mechanism is sometimes used in sewing-machines.

Eade's pulley-block,-)- schematically represented in Fig. 437, is another application of the same mechanism. It is again placed on u and driven by e. The link b = C......P is omitted, and the higher pairing described in 76, Figs. 269 and 270, is employed in its place. The formula of the train is therefore (C- L P J -C'^C~')l-'b.

The same mechanism, with the same reduction, has been used by WilcoxJ and also by Taylor in counters or numbering machines.

the same mechanism also in capstans.
 * Genie Industriel, 1869, vol. xxxvii., p. 29. Caird and Kobertson have applied

t The Engineer, 1867, p. 135. $ Engineering, January, 1869, p. 38.

Engineering, July, 1869, p. 1.

K P P

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