Abstract: An inked ribbon of a high-speed printer for office machines is wound on two spools connected each one with a corresponding electric motor. The ribbon is transferred stroke by stroke from the feed spool to the take-up spool with a substantially constant tensioning force. To this end an oscillating lever is disposed between the two spools and, cooperating with the ribbon, forms a loop thereof under the action of a tensioning spring. The oscillating lever in correspondence of a minimum and of a maximum of the ribbon loop cooperates with a pair of microswitches which alternately stop and actuate the electric motors in manner that the ribbon is transferred alternately from the feed spool to the loop and from the loop to the take-up spool under the action of the tensioning spring. A changeover device alternates the function of the two spools when the ribbon is fully wound on the take-up spool.

Abstract: In an office machine keyboard comprising a plurality of keys formed by an array of areas of layer of elastic material, each key is provided with an identifying character in relief on an insert. The insert is embedded in the elastic layer so that the character is visible on the fingering surface of the layer, is surrounded by the material of the elastic layer and contrasts in color with the material. The insert is provided with internal passages. The elastic material engaging the internal passages forms struts interlocking the inserts in the elastic layer.The keyboard is formed by injection of a hot elastomer in a moulding die in which are positioned the inserts.

Abstract: A direct current motor driving and control system comprising a permanent-magnet direct-current motor with a rotor winding not having an iron core, a source of a reference voltage which rises in magnitude with a certain slope to a normal running level in response to a start command and falls again with a certain slope in response to a stop command, a drive circuit responsive to the reference voltage for feeding energizing current to the rotor winding, a resistor in series with the motor arranged to develop a feedback voltage proportional to the speed of the motor and a combining circuit arranged to apply the feedback voltage to act in combination with the reference voltage to establish a positive feedback action serving to compensate variations of the speed of the motor.

Abstract: In a digital electronic computer which comprises a memory including a first and a second register, the first register is receptive of a number to be converted from fixed to floating point notation and the second register is receptive of a significant zero digit with an associated decimal point. Shifting means including a register is operable to shift the contents of either register and aligning means is operable to cause shifting of the second register until the decimal point stored therein is aligned with the decimal point in the first register. Indicating means indicates whether the number stored in the first register is greater or less than one and the shifting means next begins shifting the contents of one or the other of the registers when the number is indicated greater or less than one respectively.

Abstract: A cartridge for an ink or carbon ribbon of an office machine comprises a container of parallelepipedal form in which a pair of spools are rotatable for the ink or carbon ribbon. A part of the ink or carbon ribbon extends through one aperture to the exterior of the container and returns to the interior through another aperture. Two arms are associated with the two apertures and project from the exterior of the container. The arms support the portion of the ink or carbon ribbon exterior of the container, away from the container, when the container is removed from the machine and makes the insertion of the ink or carbon ribbon arms in a lift ribbon guide upon mounting of the container on the same machine. The container is further provided with a window disposed over the periphery of one of the two spools for manually rewinding the ink or carbon ribbon on the spool after the container is mounted on the machine.

Abstract: An improved mounting mechanism for a non-impact dot matrix printing head comprising a guide for positioning the support carrying the head on a base member, a resiliently actuated mechanism for removably fixing said head to said base member, and a manually operable device for activating the mechanism to remove the support from the base member.

Abstract: A selector system for a type-bearing element of a typewriter, accounting machine or other office machines, wherein a positioning member for the type-bearing element is positioned positively by a series of cam followers movable by a corresponding series of cyclically actuated cams and controlled by selectively settable stop elements. The type-bearing element comprise a shell on which the types are distributed in rows and columns. The shell is rotatable on a support sleeve provided with two side walls external to the shell. The types are distributed in two groups selectable by a transport mechanism connected to the type-bearing element through differential gears controlled by a bistable spring and two stop elements.

Abstract: An electrothermal printing unit for writing dots matrix characters on a thermosensitive paper comprises a print head carrying a plurality of thermo-activable printing elements aligned along a printing line of the recording medium.The head is reciprocated in a direction parallel to the printing line of the recording medium. The recording medium is moved incrementally perpendicular to the direction of a line of printing in synchronization with the movement of the head and control means are provided for selectively activating the printing elements at a succession of positions of the head in each of a succession of strokes thereof in an arrangement such that each element print all the points of at least one character of the line of characters during the succession of strokes.

Abstract: A temperature-responsive record material for use in a thermographic recording and reproducing apparatus comprising a supporting sheet carrying a single layer containing, as the temperature-sensitive composition, a mixture resulting by a dispersion of a basic chromogenic compound and of an acidic compound in a binder having as assential binding agent a latex or a mixture of a latex with a non-ionic cellulose ether.

Abstract: A device for reading from and writing on, magnetic cards for use in a desk-top computer having a cover with an introduction slot and an exit slot for the cards. The device comprises two parallel guides between the introduction and exit slots for defining the path to be traversed by the cards, two support plates for the guides disposed perpendicular thereto for guiding the lateral edges of the cards and a belt cooperating with pressure rollers to entrain the card as it passes through the guides. The device also includes a microswitch and a shoe which has two projections contacting the non-magnetizable face of the card, the shoe being hinged on a lever actuating the microswitch when the card has passed below the projections.

Abstract: A magnetic information recording and reading device is embodied in an electronic equipment for the data processing. On a plurality of parallel tracks of a magnetic tape are recorded information blocks aligned at the starting point so as to form a matrix of information blocks. Each column of information blocks is addressable by a corresponding address recorded in a further track of the tape. Each address block comprises a timing character sequence for the addressing of an information block and for synchronizing the reading and/or the recording of data. The energization of a recording head is controlled by the readinng of timing character included in the corresponding address block so that the recording starting point of each of the information blocks are perfectly aligned independently from the speed of the tape.

Abstract: An electroerosion apparatus utilizing a wire electrode supported at opposite sides of a workpiece is adapted to cut a given profile in the workpiece with a rake by shifting the electrode supports and thereby inclining the electrode with respect to the cutting plane. The electrode supports are at the end of two arms which can move in coordinate axes in conjunction with the movement of the workpiece table to define the profile by means of orthogonal coordinate control.

Abstract: This apparatus is used for recording and/or playing back a magnetic tape contained in a cassette provided with a hole for receiving a capstan roller and edge apertures for receiving a pressure roller adapted to press the tape against the capstan roller and a recording and/or reading head. The pressure roller is rotatably mounted between two parallel support levers which are pivotally mounted on the base about the same pivotal axis. A third lever pivoted about the said axis is coupled to the support levers by a lost motion coupling allowing limited relative pivotal mouvement between the support levers on the one hand and the third lever on the other hand. This apparatus further comprises a single actuation member which is movably mounted on the base to move the third lever to a position in which the pressure roller is moved into its position of engagement.

Abstract: A serial printing device comprises a type drum rotatably mounted on a carriage which can move parallely to a platen. On the periphery of the type drum are mounted a plurality of character-bearing elements urged against the drum by biasing means. A stepping motor rotates the drum for positioning a selected character-bearing element in front of the platen. A hammer is actuatable for pushing the selected character-bearing element radially outwardly relative to the drum against the action of the biasing means, and the drum is moved towards the platen simultaneously to the actuation of the hammer.

Abstract: An automatic text processing system, wherein a text is printed by a typewriter and simultaneously recorded line by line in corresponding blocks of a magnetic tape. The system automatically prints the address of the block in which each line is stored, whereby an operator can cause the system to print selected lines of the text by posting the corresponding addresses on the typewriter. The lines or paragraphs of a text can be cancelled or added and their succession can be changed, by posting the addresses of the lines which are to be cancelled, added or shifted in the text. The fair copy is then automatically printed with the lines justified according to a format selected by the operator. According to another embodiment the system can be used to automatically search the information recorded on the magnetic tape.

Abstract: A data processing unit having a plurality of hardware data processing circuits each one including a program counter register for addressing the microinstructions, an accumulator register and an addressing register for storing the addressing of the operands of the microinstructions. Means are provided for switching the CPU from the hardware data processing circuits having a predetermined priority level to the hardware data processing circuits having a less priority level, by executing a particular microinstruction, which includes information either about the changing of the priority level or about the memory address of the starting microinstruction of the microprogram to be executed on the less priority level.

Abstract: An horizontal tabulation apparatus wherein a plurality of sensing elements defines code combinations corresponding to the tabulation positions and divides a plurality of cams in groups each associated with predetermined tabulation positions; stopping means are actuated by the plurality of sensing elements when the groups generate the same code combination in correspondence with tabulation positions associated therewith.

Abstract: Numerical control means for controlling the position of a machine tool or the like by means of a servomotor are described. A position command signal is compared to the signal indicative of the servomotor position, and the resultant error signal is added to a speed command signal to control the speed of operation of the motor. A follow-up signal is generated whenever the amplitude of the error signal exceeds a predetermined level, and the latter is added to a digital position signal coupled to the system. A constant digital signal generated by said follow up signal is added to said error signal instead of said speed signal.

Abstract: This invention relates to liquid crystal display devices. One aspect of the invention concerns the electrolytic growing of projections on one plate of the device so that the projections register with the tin-oxide segment array on the other plate; another aspect concerns utilizing similar projections as internally placed spacers. An insulative sheet is deposited over the segment array in order to filter D.C. components, according to a third aspect of the invention, and, according to a fourth aspect, a spacing technique is disclosed which utilizes alumina particles in a glass matrix as an edge spacer. Further, a light concentration technique, utilizing a one-way mirror and a prism or fiber optic assembly, is disclosed.

Abstract: A desk-top electronic computer with MOS circuit logic comprising an input device, an output device and a logic unit adapted to carry out the various operations of the computer. The logic unit is disposed on at least two MOS circuit chips synchronized by a main oscillator. Each MOS chip is provided with a corresponding timing circuit adapted to generate mutually coordinated timing signals. The logic unit includes a read only memory or ROM for storing the microinstructions commanding the various functions, a computing unit and a control unit adapted to permit the selection of the microinstructions from the ROM by addressed access for the purpose of supplying a sequence of microinstructions to the computing unit, access of the address and output of the microinstructions taking place through a single connection between the ROM and the control unit.