Page:Motors and motor-driving (1902).djvu/155

misses f. Consequently, instead of the valve being raised, it remains shut.

We shall now explain how this is accomplished. The arm h, commonly known as the hammer, is the direct medium through which this change is effected. It will be seen in fig. 14

Fig. 14

Fig. 15

a, frame carrying the bearings for two-to-one shaft b; b, two-to-one shaft; c, bracket forming portion of hammer h, and carrying connecting rod j, which operates the digger k; d, arm mounted on spindle i; e, circular collar on two-to-one shaft; k, shoulder on arm d, to engage digger k; g, eccentric cam on two-to-one shaft; h, hammer; l, cam operating exhaust valve; r, roller actuated by cam l.

that it rests on a perfectly circular collar, e, whereas in fig. 15 it has mounted on to a cam, g, which is fixed eccentrically on to the shaft b. This cam g is so mounted on shaft b, that when the protruding portion of cam l is pushing up the roller r, the hammer h rests on cam g, at the maximum