Page:The Kinematics of Machinery.djvu/470

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KINEMATICS OF MACHINERY.

Fig. 307, or, bearing in mind the invertibility of the lower pairs,

to the piece C + L...C+ in Fig. 308. Brasses, screws, cover, bolts

and so on serve only to complete constructively the element C~ and to secure it to the floor or building. The compound bed-plate

FIG. 304.

Fig. 309 may be represented (always supposing the addition of the plummer blocks) by the four elements C~ of the frame shown in

Fig. 310.

FIG. 305.

In the design of any machine it is very advantageous to begin by representing in this way the simple kinematic forms which form the basis of the framing, bed-plates, brackets and structures which