Page:The Kinematics of Machinery.djvu/364

 CHAPTER IX.

ANALYSIS OF CHAMBER-CRANK TRAINS.

78.

Chaining of Crank Mechanisms with Pressure- organs.

HAVING now made ourselves familiar with the application of kinematic analysis to the various forms of the simple crank chain, we may go a step further, and may proceed limiting ourselves still to the same class of mechanisms to examine the extent to which this analysis is applicable to actual machines. When we have completed this examination we may hope to have made the road to the practical use of the analysis sufficiently evident and easy.

Among the numberless applications of the crank chain in machinery one special class claims our attention, that namely in which a pressure-organ, water, air, steam, gas, &c., is used in kinematic combination with the mechanism, so as to produce either a machine for moving the pressure-organ, such as a pump, or its contra-positive, a machine driven by the pressure-organ, an engine or "prime-mover." The combinations employed for these two purposes must obviously have a very close relationship, and a great number of the chain forms which we have considered have