Abstract: A ribbon cassette is selectively mounted in a printing device having an operating mechanism actuable between locked and released states. The ribbon cassette has a casing for accommodating therein a print ribbon that cooperates with the operating mechanism for printing characters. The cassette also includes an actuating mechanism for mechanically unlocking the operating mechanism to the released state when the casing is inserted into the printing device. In a preferred embodiment, the actuating mechanism is a projection on a wall of the casing that abuts a locking linkage within the printing device and moves the locking linkage to unlock the operating mechanism.

Abstract: Disclosed is a data entry keyboard which has a multitude of depressible keys which are selectively depressed for the entry of predetermined data. In the keyboard, an insulating member is sandwiched between a first substrate having stationary electrodes and a flexible second substrate having movable electrodes. The stationary and movable electrodes face one another through apertures formed in the insulating member. Upper and lower marginal surface portions of the insulating member, including the respective peripheral edges of the apertures, are kept parallel to the first and second substrates corresponding thereto by a plurality of protuberances on the substrates so that voids with a predetermined width are left between the marginal surface portions and the individual substrates. The movable electrodes of the second substrate are electrically fixed, in the form of a cantilever each, to the extreme end portions of branch conductor strips which diverge from a main conductor strip at right angles thereto.

Abstract: A ribbon driving mechanism for a typewriter, having a cam member provided on one side thereof with a first cam section for effecting control of a printing ribbon, and a second cam section extending continuously from the first cam section for effecting control of a correction tape, and a stopping member for controlling the movement of a cam follower along the cam sections. Either the printing ribbon or the correction tape is moved selectively to the printing position and only the rotation of a motor for driving the cam member in one particular direction, is transmitted to a printing ribbon winding mechanism, to wind the printing ribbon.

Abstract: A typewriter driven by an electric motor and provided with a ribbon vibrator for moving an erase ribbon in place of an ordinary printing ribbon as an occasional substitution from original position to printing position according to operation of a printing device for common use to both to erase a mistyped character. The ribbon vibrator is normally retained in non-operative status by a retaining member, which is moved in response to depression of a correction key to a predetermined evacuation position to allow the ribbon vibrator to operate and locked there by a lock member. The lock member is associated with not only a release key but also a manual switch member for controlling power supply to the electric motor. The engagement between the lock member and the retaining member is released in response to a turning operation of the manual switch member to OFF position for automatically restoring the ribbon vibrator to the non-operative status.

Abstract: The typewriter has a powered motor, an electric power switch, a drive shaft driven by the motor, a driven mechanism including printing and carriage return mechanisms connected to the drive shaft by way of respective clutches, and locking device for locking the clutches in their disconnect state. The locking device consist essentially of a cam portion on a manually operable member designed for turning on and off the switch, and a locking element actuated by the cam portion. When the manually operable member is actuated for turning off the switch, the clutches are locked in their disconnect state by the cam portion through the locking member. During cessation of the motor operation, these clutches may not be connected by faulty manipulation of the key or keys associated with the driven mechanism for reliably preventing incidental printing or carriage return movements upon restarting of the motor from occuring.

Abstract: The typewriter has a drive mechanism including a vibrating mechanism and a feeding mechanism for a correction ribbon. The vibrating mechanism has a pair of ribbon vibrators, a cam follower provided to one of the vibrators, an eccentric cam designed to make one complete revolution for each printing operation in response to depression of associated key, and a spring member for resiliently biasing the cam follower toward the peripheral surface of the eccentric cam. The feeding mechanism has a pair of spindles for carrying ribbon spools, a ratchet wheel mounted on one of the spindles and a feed lever connected to the other vibrator. Upon depression of a correction key for setting the ribbon vibrators to be actuatable, followed by depression of an alphanumeric key, the ribbon vibrators are actuated by rotion of the eccentric cam so that the correction ribbon is raised from its inoperative position to its operative position.

Abstract: A typewriter with a character erasing apparatus capable of consecutively erasing a series of characters as well as a single character once printed on a sheet of printing paper. The typewriter is provided with a retaining crank movable to first, second and third positions. In the first position the retaining crank retains a ribbon vibrator supporting an erase ribbon in non-operative status. In the second position the retaining crank permits the ribbon vibrator to operate while interrupting transmission of power for moving a platen. The retaining crank is automatically restored to the first position in response to return movement of the ribbon vibrator after the single character erasing. The retaining crank is moved to and held at the third position by a manual member for permitting the ribbon vibrator to operate consecutively. The retaining member does not interrupt the transmission of the power for moving the platen.