The present invention relates to a correction device for typewriters, in particular electronic typewriters.
In U.S. Pat. No. 4,462,707 a typing and correction device in electronic typewriters comprises a frame structure which is pivotally mounted on a movable carriage slidable parallel to the platen roller. A cartridge with a typing ribbon and two reels with a corresponding ribbon are mounted on the frame structure which is controlled by two solenoids, of which a first positions the typing ribbon in front of the platen roller and a second positions the correcting ribbon when a correction cycle is to be carried out. In that arrangement the correcting solenoid has to perform the operation of lifting and advancing the correcting ribbon. That solenoid is fairly large and therefore expensive. In addition, for actuation thereof, it requires an electronic power circuit which is also costly.
USPTO Backgrounds
USPTO Backgrounds