Error correcting typewriter ribbon system

摘要

An error correcting typewriter having separate elevating and feed mechanism for carbon and error correction ribbons includes a common cyclic motive source operable in response to type commands to drive a cam shaft which is axially shiftable by means of an electromagnet energized by a correction signal. Normally, the cam shaft is positioned in engagement with a carbon ribbon drive lever and out of engagement with an error correction ribbon drive lever. A shift of the cam shaft disengages it from the carbon ribbon drive lever and engages it with the error correction ribbon drive lever. The carbon ribbon drive lever simultaneously operates a carbon ribbon elevating mechanism and a feed mechanism. Energization of the electromagnet operates a lever which directly operates the correction ribbon feed mechanism and simultaneously shifts the cam shaft to engage it with the error correction ribbon drive lever which when driven is operative on the correction ribbon elevating mechanism.