As soon as the first
matrix has escaped, the escapement resumes its original position, the
upper pawl falling, while the lower one rises so as to hold the second
matrix, which assumes the position previously occupied by the one
released.
[Illustration: Fig. 6.]
Thus it is that the alternate rising and falling of the two escapement
pawls permits the matrices to escape one at a time. It is evident that
the escapements could be operated directly by rods connected with the
finger-keys, but this direct connection is objectionable because of the
labor required on the part of the operator, and the danger that the keys
may not be fully depressed. Moreover, it is essential that the
escapements should act individually with moderate speed to the end that
the matrices may be properly engaged and disengaged by the pawls. For
these reasons, and to secure easy and uniform action of the parts, the
mechanism shown in Figs. 5 and 6 is introduced between the finger-keys
and escapements. The vertical rods _C_, which actuate the escapements,
are guided in the main frame, and each is urged downward by a spring
_c_.
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