Abstract: A cartridge for a typing ribbon for typewriters comprises a container for accommodating a typing ribbon which can be of single-strike correctable or non-correctable, multi-strike or endless inked type. If the ribbon is of the single-strike or multi-strike type, the container comprises a supply reel and a tensioning and stop device co-operating with a toothed flange of the supply reel to prevent the ribbon which is wound on the supply reel from unwinding both when the container is mounted on the machine and when it is removed from the machine. The device comprises a tensioning lever for the ribbon and a stop lever for the reel, which levers are connected together by means of a resilient spring connection. The device guides and tensions the ribbon during the unidirectional feed movement thereof, in such a way as to ensure a constant stepping movement in the feed motion of the ribbon and low and constant tensioning of the ribbon.

Abstract: A cartridge for a correction ribbon for typewriters comprises a container for a supply reel and a receiving reel. A tensioning device comprises a toothed ring on the supply rell and a spring which is pivoted in the container and which has one end engaged with the toothed ring to tension the ribbon. The container can be removably fixed to the lower part of a cartridge for a typing ribbon which in turn can be fitted on a support of the machine. The support is movable from a viewing position to a typing position in which the typing ribbon is in front of the point of typing and to a correction position in which the correction ribbon is in front of the point of typing. The receiving reel of the cartridge, in use, is capable of co-operating with a feed mechanism which provides for forward feed movement of the ribbon in each correction cycle.

Abstract: A cartridge for a typewriter typing ribbon comprises a container for accommodating the typing ribbon which can be of correctable or non-correctable type. A corrector cartridge can be removably fixed on the lower part of the container by engagement means. The corrector cartridge accommodates a correction ribbon which can be of the lift-off type suitable for the typing ribbon of correctable type, or of the cover-up correction type which is suitable for the typing ribbon of non-correctable type. Coupling means on the cartridge and the corrector cartridge permit the engagement means removably to fix the corrector cartridge to the container only when the caartridge houses the typing ribbon of correctable type and the corrector cartridge houses the correction ribbon of lift-off type or alternatively when the typing ribbon is of non-correctable type and the correction ribbon is of the cover-up type.

Abstract: A cartridge for a printing ribbon for a typewriter having a character-carrying disc comprises a casing and two oscillating arms between the ends of which a run of the ribbon extends in a straight line on the outside of the casing between the disc and the platen. The arms oscillate from a rest position in which they make the typing point visible, to three or more working positions in which they make it possible to print using one of three tracks of the ribbon. The two oscillating arms are pivoted by means of pins on seats of fixed supports of the casing. Pivotally mounted at the free end of each arm is a guide element, a stem of the guide element being received in a sleeve of the arm. Each guide element is thus capable of modifying its angular position with respect to the respective arm in response to the selection movement so that the ribbon is always held in tension in a uniform manner, irrespective of the track selected.

Abstract: The print apparatus comprises a character-carrying element of the `daisywheel` type with flexible spokes which can be selectively positioned in front of a platen roller, a print hammer for moving a selected character towards the platen roller, an actuating solenoid for the print hammer and a damping mechanism which acts on the hammer after the printing of each character. The hammer is directly connected to a movable armature of the solenoid and is returned by a return spring.During the return phase, the armature displaces, against a travel limiting stop, a counteracting weight which is urged towards an intermediate stop by the force of a counteracting spring. A first damping element is disposed between the movable armature and the counteracting weight and a second damping element is disposed between the weight and the travel limiting stop. The two damping elements, operating sequentially, minimize the time required for the hammer to settle down.

Abstract: The sheet feeder can be mounted on a typewriter or on a printer in a system for processing data. The sheets which are accommodated in a feed magazine are passed to the platen roller by friction stripper rollers. After the printing operation, the sheets are passed on to a collection table positioned in front of the feed magazine. The stripper rollers are permanently connected to the platen roller by way of a mechanical transmission and rotate in the same direction as the platen roller. The stripper rollers are mounted on an oscillating arm to be selectively moved towards or away from the first sheet to be fed, by means of a first cam. Before a fresh sheet is fed, a second cam, also coupled to the platen roller, has to be brought to a reference position by rotating the platen roller enough to expel the current sheet. The platen roller is then rotated in the reverse direction, whereby the second cam actuates a lever, thereby to close a clutch.

Abstract: A document feed-in device for an electronic typewriter comprises a lower guide member for guiding a document towards a typing line on a platen cylinder and a plate or bar member for guiding the document beyond the typing line. The plate or bar member is carried by two movable levers for moving that member away from the platen cylinder and at the same time actuating a switch for signalling the presence of the document to the electronic control means of the machine, to cause rotation of the platen cylinder so that the document goes beyond the typing line by a predetermined distance such that the top edge of the document is moved into a region in which it is engaged by the plate or bar member to permit typing in a region immediately adjacent to the top edge of the document.

Abstract: The printing and correcting device is applied to a daisywheel printer and comprises a frame supporting a cartridge for a typing ribbon and a correcting ribbon arranged below the typing ribbon. The frame is able to swing as the result of operation of an electromagnet, from a rest position providing visibility of the print, to an intermediate position for printing the characters. A second electromagnet raises the frame through a greater length of travel in order to position the correcting ribbon in front of the printing point. A rotating electromagnet causes automatic unidirectional advance of the typing ribbon after each character has been printed. The correcting ribbon is wound between two spools and its motion is provided by means of a pawl which engages with a gear wheel for driving the spool only in the case where the path of travel of the frame is greater than that which relates to positioning of the typing ribbon.

Abstract: The printing and correcting device is applied to a daisywheel printer and comprises a frame supporting a cartridge for a typing ribbon and a correcting ribbon arranged below the typing ribbon. The frame is able to swing as the result of operation of an electromagnet, from a rest position providing visibility of the print, to an intermediate position for printing the characters. A second electromagnet raises the frame through a greater length of travel in order to position the correcting ribbon in front of the printing point. A rotating electromagnet causes automatic unidirectional advance of the typing ribbon after each character has been printed. The correcting ribbon is wound between two spools and its motion is provided by means of a pawl which engages with a gear wheel for driving the spool only in the case where the path of travel of the frame is greater than that which relates to positioning of the typing ribbon.

Abstract: A hammer assembly for a serial typing device which comprises a character bearing disk having a central hub and a plurality of flexible laminae radiating therefrom each carrying a particular character. The hammer assembly comprises a hammer which is actuatable for selectively causing the lamina of the selected character to strike against a sheet bearing platen for typing. The hammer is directly fixed to the armature of a plunger electromagnet which is energizable with a substantially constant current. The fixed pole pieces of the electromagnet and the armature connected to the hammer have pole surfaces inclined with respect to the longitudinal axis of the hammer, so that the impact force of the hammer varies directly as the energization time of the electromagnet while it remains substantially constant during the entire stroke of the hammer.