Abstract: The device comprises a flange (14) which is fixed to the shaft (12) of the motor and which is provided on its front face with a plurality of radial teeth (28) spaced by recesses each having their active side surfaces parallel to each other and to the radial line through the recess. Removably connected to the character-carrying disc (11) coaxially therewith is another disc (35) of smaller diameter which is provided on its outward front surface with radial teeth (48) having their active side surfaces (50) parallel to each other and capable of being coupled to the radial recesses of the flange which is fixed to the motor shaft. On the other front surface, hooks (38, 39) engage in holes (21, 23) in the disc. In an alternative embodiment the teeth (48) are integral with the hub (16) of the disc (11) itself.

Abstract: A device for reading graphic symbols impressed on a sheet, comprising light sources for illuminating the sheet, an optical reading system and an array of photo-electric sensors for generating electrical reading signals. The device is compact in structure and of small dimensions, so as to allow it to be mounted upon the head-carrying carriage of a printing machine or typewriter. The device makes it possible to create, in a particularly simple form, reading apparatus for facsimiles or for optical character recognition (OCR) reading apparatus for memorizing signatures, graphical symbols and drawings or mathematical symbols, or apparatus for copying documents.

Abstract: A device for controlling the rotary movement of a platen roller of a typewriter comprises a bidirectional electric motor coupled to the platen by a worm gear and gear wheel and a pair of knobs which are disposed at the sides of the platen and which are rotatable with respect thereto. The knobs are fixed to a bar which extends rotatably through the platen roller and carries the gear wheel. Selective bidirectional rotation of the knobs causes corresponding rotary movement of a disc in a transducer. The disc has a toothed sector in mesh with the gear wheel and is the moving part of a rotary switch which generates electrical signals which determine both the power supply to the electric motor and the direction of rotation thereof. Small degrees of rotary movement of the knobs against a first spring force establish continuous rotary movement of the platen roller at low speed. A further slight rotary movement of the knobs against a stronger spring force establishes rotary movement of the platen at high speed.

Abstract: The device comprises two or more cover plate members (14), whose lengths are submultiples of the lengths of a range of platen rollers (12) and such that two or more plate members disposed in side-by-side relationship cover the entire length of the platen roller. Each plate member (14) comprises a lower guide portion (16) of part-cylindrical shape and two wall portions (17, 18) which are substantially planar and set at different angles of inclination, being connected to the lower guide portion in such a way to lead in a sheet of paper (19) towards the guide portion. Each plate member (14) is pivotally mounted on a control shaft (22) which is parallel to the axis of the roller (12) and capable of preventing transverse movements of the plate member with respect to the roller, and carries the usual paper pressing rollers (34, 36) which are disposed in two parallel rows. A leaf spring (26) co-operates with a lug (24) on the plate member (14) to hold the paper pressing rollers pressed against the platen roller.

Abstract: An optical transducer for detecting the angular position of a rotary member with respect to a fixed structure, which comprises a shutter disc of transparent material, having two faces which are parallel to each other. The disc is provided with a plurality of radial shutter elements, spaced by elements which transmit the light. The shutter elements are formed by V-shaped elements provided on one face of the disc and capable of totally deflecting the light incident thereon.

Abstract: A cartridge for the inked ribbon of a calculating or other office machine, of the type comprising a platen, a plurality of printing styli disposed in front of the platen at a short distance therefrom, a motive shaft, two fixed stops for transverse positioning of the cartridge with respect to the platen and a longitudinal positioning block. The cartridge comprises a container of substantially parallelepipedal form having a larger side provided with a recess defining two lateral arms. An inked ribbon closed in a loop is disposed inside the container and extends therein between an inking roller and a ribbon tensioning element. The ribbon has a substantially rectilinear portion which emerges from the said lateral arms and spans the recess, parallel to the larger side.

Abstract: A selector for a keyboard of a calculating machine comprises a series of sliders for indicating information relevant to operations to be performed and a plurality of switches driven by the sliders for the entering of this information in the machine. The sliders are slidably mounted on a common support, in front of which there is mounted the support of a printed circuit. A series of movable contacts, carried by the sliders, are actuatable by the sliders to contact the fixed contacts for the input of the said information.

Abstract: A device for inking the type-carrier element of a calculating machine or similar office machine. The type-carrier element includes a wheel from the edge of which protrudes corresponding characters. These are selected by a recording support for the rotation of the wheel and define the various writing positions for the movement of the wheel along a line of writing. The device includes a container with an ink-deposit element inside it and which has a long window substantially the same length as the line of writing and covered with a permeable, wear-resistant layer which is in contact with the deposit element in order to permit the outflow of the ink. A spring element keeps the said permeable layer tight against the type-carrier element during the rotation and movement of the wheel.