Abstract: In an electrostatic copier including a device for the electrostatic transfer of a toner image disposed on an electrophotographic recording material to an image receiving material whose rear side is chargeable by a corona discharge device composed of an elongate electrically conductive shielding housing and at least one corona discharge wire clamped in an insulated manner between the housing ends, there are provided: a carrier to which the corona discharge device is fixed; a slide member supporting the carrier and with respect to which the carrier is movable between two end positions for setting the distance between the corona discharge device and the surface of the recording material; a control member connected for moving the carrier between its end positions; guide rails extending parallel to the recording material surface and fixed to the copier; and guide elements fixed to the slide member and arranged to travel along the rails to guide the movement of the slide member, the guide elements being removable f

Abstract: An optically coded keyboard arrangement has a plurality of key units arranged to be individually actuated; an actuation sensing arrangement that includes a plurality of light emitters generating light beams and a plurality of detectors each placed in the path of a respective light beam. Each key unit includes a key arranged to be depressed and a coded mask coupled to the key for movement with the key in unison upon displacement of the key and for movement relative to the key in a direction transverse to the path of motion of the key. Each key unit further has a switching spring which, in the position of rest of the associated key has an arcuate shape bulging in one direction and engages at one end a countersupport. As the key is depressed, the switching spring is deformed into a more bulging shape, carrying the mask into a position where it is ready to interrupt the light beams.

Abstract: A feed mechanism for advancing a cartridged ink ribbon in feeding steps whose length is determined dependent upon the type of the ribbon contained in the ribbon cartridge. The feed mechanism includes a feed roller mounted in the cartridge and operatively connected with the ribbon for advancing the ribbon. The feed mechanism further includes a driving device mounted in the machine and operatively connectable to the drive roller upon insertion of the cartridge in the machine. The driving device has at least two output components arranged to rotate with unlike speeds. The feed mechanism further has a coupling arrangement mounted in the cartridge and continuously operatively connected with the feed roller. The coupling arrangement connects a selected one of the output components to the feed roller when the cartridge is in place in the typing machine.

Abstract: The nozzle surface of an ink writing head installed in an ink printer is cleaned by bringing a liquid-absorbing cleaning medium into contact with at least those portions of the nozzle surface which surround the nozzle outlet openings, maintaining such contact for a period to permit ink to flow from the nozzles in the direction toward the cleaning medium and to be absorbed by the cleaning medium, whereby such nozzle surface portions are wetted by a liquid phase in which particles to be removed are dissolved, and removing the cleaning medium from the nozzle surface in order to carry such particles away from the nozzle surface. Preferably, the absorbing medium exhibits capillarity and possesses capillary passages smaller in diameter than the nozzles and presents a contact angle of less than 90.degree. with the ink.

Abstract: An electrophotographic copier includes a replaceable photoconductive sheet having a leading edge portion and a trailing edge portion; a guide drum rotatably supported by a drum shaft and having a holding device for securing the leading sheet edge to the guide drum; a charging station, an illuminating station, a developing station, a transfer station and a conductive sheet cleaning station arranged in a circumferential distribution about the guide drum. The leading edge of the photoconductive sheet is attached to the guide drum and, upon rotation of the guide drum, a pressing roll, brought into engagement with the guide drum by a control mechanism, presses the trailing edge of the photoconductive sheet on the leading edge, as a result of which, by means of an interposed adhesive, the photoconductive sheet is bonded together to form an endless band about the guide drum.

Abstract: In a device for developing electrostatic charge images produced on the surface of a sheet of electrophotographic recording material in a copier which employs a magnet having on its surface a magnetic brush formed of magnetizable toner particles, the copier further presenting a recording material sheet guide path which extends at a distance from the magnetic brush, there are provided contact elements which are disposed in the guide path and which are arranged to be controlled by the leading edge of a sheet of recording material in a manner to be brought into contact with the sheet along a line which lies behind its leading edge to press the recording material against the magnetic brush, the contact elements being controlled in a manner such that they are lifted away from the sheet shortly before reaching the trailing edge thereof in order to prevent the contact elements from contacting the magnetic brush.

Abstract: A carriage guide for supporting a typing element carrier and composed of two guide rails extending parallel to a printing abutment, and pairs of guide rollers mounted on intersecting axes and connected with the typing element carrier for centering the typing element carrier at at least one of the guide rails, is further provided with first and second roller carriers carrying the guide rollers at sides thereof extending parallel to the rails, the roller carriers being disposed to intersect one another and the second roller carrier being provided with a slide edge, elements defining a common joint extending between, and parallel to, the guide rails and via which the carriers bear against one another, a tensioning spring element acting between the roller carriers, a receiving element carried by the first roller carrier at one of its sides parallel to the rails for establishing an articulated connection with the typing element carrier, and a supporting spring element cooperating with the slide edge for effecting

Abstract: A typing device includes a frame; a drive shaft rotatably supported in the frame; a type disc arranged in the frame for being rotated by the drive shaft; a conically centering bearing assembly situated between one side of the type disc and a frame part; a coupling arrangement for torque-transmittingly and axially relatively displaceably connecting the type disc to the drive shaft; and a spring axially urging the type disc against the frame part for a conical centering of the type disc on the frame part by the bearing assembly.

Abstract: In a key-operated machine in which actuation of a key moves code elements of an associated code card into the path of a photoelectric sensing system, each code card is moved by a drive mechanism so as to cause the code elements to traverse the sensing system path only once, and at a speed which is independent of the speed of key movement, in response to each key actuation.

Abstract: An aqueous black ink for a writing process in which ink is transferred in droplets onto a print carrier. The ink comprises 25-42 g./l. of the direct Diamine Blue 6B, extra high concentration; 14-22 g./l. of the direct dye Diamine Scarlet 4BS, extra concentration; 290-430 ml./l. of formamide; 32-48 ml./l. of 90% diethanolamine, 24-60 g./l. of citric acid, a water-soluble and organic soluble disinfectant, and balance essentially water. A process for producing such an ink comprises the steps of mixing both dyes together; introducing the mixture at room temperature in incremental portions into the formamide and stirring until the dyes are substantially completely dissolved. Undissolved salts are removed from the mixture. Diethanolamine and distilled water are introduced under agitation into the mixture. The pH is adjusted to about 6 to 8 with citric acid and disinfectant is added. The mixture is filtered under vacuum and then gases are withdrawn by treating the mixture under a vacuum.

Abstract: A cleaning device for wiping the cylindrical face of a roll supported for rotation has an elongated frame comprising a plurality of elongated support webs oriented at an angle to one another in a star-like configuration; a cleaning felt secured about the frame and supported by the free longitudinal edges of the support webs; pressing levers movably supported adjacent the roll and including a frame supporting arrangement for rotatably holding and positioning the frame at opposite ends thereof, parallel to the axis of the roll; and a spring connected to the pressing levers for urging the pressing levers towards the roll for pressing the frame against the roll into a working position. The cleaning felt is divided into a plurality of cleaning felt portions by any two neighboring free longitudinal edges. In the working position, one of the cleaning felt portions is urged into a shape-conforming engagement with the cylindrical face of the roll along the length thereof.

Abstract: A typing device has a type disc which includes a plurality of bars each carrying a character and which is rotatable about an axis through predetermined angles for successively setting selected characters in a printing position. The typing device further has a hammer for impacting the bar of the selected character for pressing the selected character against a record carrier supported by a platen. The type disc carries a plurality of stops; each stop is assigned to a different character. The stops are arranged at least at two different distances from the disc axis, dependent upon the printing surface area of the associated character. The typing device further has an elastic lever, one end of which is movable into an abutting engagement with the stop of the associated character situated in the printing position. Another end of the elastic lever is connected to the hammer so that the hammer and the elastic lever are moved simultaneously by a hammer drive.

Abstract: A device for the pressure fixing of a toner on a record carrier under ambient temperatures has a stand; a first pressure roll of relatively large diameter rotatably and stationarily supported in the stand; and a second pressure roll of relatively small diameter rotatably supported in the stand and cooperating with the first pressure roll to define therewith a roll gap. The second pressure roll is displaceably supported to be shiftable towards and away from the roll gap. The device further has a plurality of pressure rollers arranged in a series along the length dimension of the second pressure roll in an axially parallel orientation therewith and a support for individually displaceably supporting each pressure roller for movement towards and away from the roll gap. A separate spring urges each pressure roller into contact with the second pressure roll for exerting thereon a pressing force with which the first and second rolls compress a record carrier passing through the roll gap.

Abstract: An apparatus for controlling the flow of ink in the nozzle of an ink ejector head, the latter having an ink flow system which has a chamber capable of being supplied with ink and a nozzle through which ink is ejected as well as a pressure producer capable of being subjected to pulses for applying pressure on the ink in the chamber so as to cause the ink to be ejected through the nozzle. The pressure producer has applied to it a series of pulses consisting of alternating primary and secondary pulses, the latter occurring a predetermined time interval subsequent to the cessation of the application of the immediately preceding primary pulse.

Abstract: An aqueous ink for an ink ejection process, particularly a blue ink for a process employing an ejection system which produces droplets, comprises (a) a water soluble triphenyl methane dye and (b) a buffer mixture of at least one organic hydroxy-containing carboxylic acid and at least one water soluble amine.

Abstract: A centrifugal coupling for connecting a driven rotary component with another rotary component has a pair of flyweights mounted on the driven component for pivoting about pivot axes which are so spaced from one another transversely of the axis of rotation of the rotary component that straight lines intersecting the pivot and center of gravity of the respective flyweight will extend parallel to a plane of symmetry passing through the axis of rotation intermediate the flyweights when the coupling is in an operating position in which it centrifugally couples the two components for joint rotation.

Abstract: A push button switch mounted on a conductor-carrying insulator plate includes a push button to which an external operating force can be applied; an electrically conducting, resilient switch element carrying a movable contact and arranged on the plate within the operating range of the push button for effecting at least an indirect transmission of the operating force to the switch element; and at least one fixed contact carried by the plate. In the operating position the movable contact is in engagement with the fixed contact. The switch element is constituted by a planar sheet member having a central zone bounded by two parallel edges and carrying the movable contact, and strip-like legs integral with the central zone and extending from the edges towards the insulator plate at an inclination with respect to the central zone that is greater than 90.degree.. The legs are supported at least indirectly on the insulator plate at conductor-free portions thereof.

Abstract: In a circuit arrangement composed of highly integrated chips for a microprogrammed data processing device of the type including an arithmetic and control unit, at least one read-only memory, at least one random access memory, connecting contacts on the chips for connection to peripheral units, and a bus connecting the chips together, each contact is connected to a function selecting unit whose operating state is controlled by a microprogram contained in the read-only memory to selectively connect the contact in the arrangement as either an input contact or an output contact. The function selecting unit includes for each contact a bistable circuit and a gating circuit controlled by the microprogram to determine when each contact constitutes an input or an output terminal.

Abstract: A circuit arrangement for data processing devices including an input keyboard with keyboard contacts disposed at the points of intersection of a conductor matrix and a multiposition data output device. The data is fed into the data processing device in such a manner that signals furnished cyclically from an electronic control circuit to a series of outputs are fed as control signals to the respective positions of the data output device and, via circuit branches, as interrogation signals to the respective row lines of the keyboard matrix which has its column lines connected to inputs of an electronic decoder for evaluating signals received via closed keyboard contacts. A transistor is disposed at each of the branch points with its emitter-collector path connected between the respective output of the control circuit and the associated position of the data output device. The base of each of the transistors is connected with the associated row line of the keyboard matrix.

Abstract: A circuit arrangement for selectively adding or subtracting two binary coded decimal numbers exclusively by means of addition operations, in which addition involves adding a binary coded decimal value corresponding to the decimal value "6" to each digit of one of the numbers to be added and adding a binary coded decimal value corresponding to the decimal value "10" when the addition of corresponding digits of the two numbers and the value "6" does not produce a carry, and in which subtraction involves forming the unit complement to each digit of the subtrahend, adding together the unit complement of each digit, to the corresponding digit of the minuend, and a value of "1", and then adding the binary coded decimal value corresponding to the decimal value "10" when the previous addition does not produce a carry.