| 摘要 |
8. In a cryptographic machine having a keyboard, and coding circuits conditionable for encipher and decipher operation: a printing device, means connecting said device to the keyboard through the coding circuits in one direction for enciphering and in the opposite direction for deciphering, and for connecting said device directly to the keyboard for printing plain text; means to feed to said device a tape upon which characters are to be printed, including a friction drive rotatable shaft, tape feed members driven by the shaft, three toothed wheels fixed on the shaft in abutting relation, a first one of said wheels having a continuous series of teeth, a second wheel adjacent thereto having two only diametrically opposite teeth higher than the teeth on the first wheel, and a third wheel adjacent the second having two equal groups of teeth with spaces equal to one tooth separating the groups and a first tooth in each group adjacent a said high tooth, a pawl slidably mounted to be engageable with any said toothed wheel to prevent rotation of the shaft while so engaged, the pawl being rockably mounted to be disengageable from a tooth of the first and third wheel each time a character is printed to permit rotation of the shaft, means to move the pawl to engage the first wheel for decipher and plain text writing, to engage the third wheel for encipher and to engage the second wheel during non-printing operation of the machine, and means actuated to disengage the pawl each time a character is printed.
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