The roll, engaging frictionally with
the cam, causes the latter to turn on its centre in the direction
indicated by the arrow in Fig. 6.
Owing to the eccentric shape of the cam, its rotation while resting on
the roller causes it to lift the yoke _c2_ above its original
position, so that it acts upon the escapement rod _C_, lifting it and
causing it to reverse the position of the escapement _B_, to release the
matrix, as plainly seen in Fig. 6.
While this is taking place, the yoke-trigger _c6_ resumes its first
position, as shown in dotted lines in Fig. 6, so that as the rotating
cam lowers the yoke, it is again supported in its first position, the
cam at the same time turning forward by momentum out of engagement with
the roll until arrested in its original position by the pin _c7_.
It will be observed that the parts between each key lever and escapement
operate independently of the others, so that a number of cams may be in
engagement with the rollers at one time, and a number of escapements at
different stages of their action at one time.
Pages:
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57