Abstract: A device for positioning a printing head of a printer in response to recording carrier/substrate thickness includes a reflex sensor arranged in a protected space formed between a head-carrying carriage and an opposing printing head housing surface. During printer initialization or upon insertion of a recording carrier/substrate having a thickness greater than a predetermined thickness, the printing head is slightly displaced with respect to the carriage as a result of brief contact of the printing head print surface with the recording carrier that is supported on a printing abutment. The reflex sensor measures the displacement travel distance of the printing head and generates an input signal to an evaluation circuit. The evaluation circuit generates an output control signal to a carriage displacement drive in response to the measured displacement of the print head to automatically set the distance between the printing head and the recording carrier or printing abutment.

Abstract: A paper transport device in printers (1), particularly in dot matrix printers, for the feeding of continuous webs (6) by transversely displaceable tractors (7, 8) which are arranged in pairs on the printer frame. The tractor pins (9) engage into the edge perforations of the continuous web (6) and the pin belts (10) are guided over at least one wheel (11) of the tractor (7, 8) and at least one driven tractor wheel (13) is present. The device is equipped with a locking device so that the tractor (7, 8) operating as push means or as pull means is mounted in each case on a drive shaft (14) and in each case prevented from turning on the printer fram (1a) by a projection (16) on the side (15a) opposite the drive shaft (14) or by a swingable tractor flap (24).

Abstract: Apparatus for the selectably alternative feeding of single sheets and of endless webs of paper in a printer includes a guide roll (7), and first and second groups (8, 9) of friction rollers concurrently movable between first and second positions to define respective single sheet and endless web feeding modes of operation. In their first positions, the first friction rollers (8) contact the guide roll (7) to define a first single sheet feed channel (4) and the second friction rollers (9) contact the guide roll (7) to define a second single sheet feed channel (5). When shifted to their second positions, the first friction rollers (8) are displaced from their first position contact with the guide roll (7) to substantially eliminate the first single sheet feed channel (4), and the second friction roller (9) are lowered to form with the guide roll (7) an endless web feed channel (6).

Abstract: A matrix printer is furnished with a matrix print head (1) supported on a back and forth movable slider (2), guided on a rail guide (3), wherein the print elements (4) can be operated at a high frequency. A matrix print head (1), disposed fixedly in its position relative to the slider (2), is furnished at least at one reference face (8) between the matrix print head (1) and the slider (2) with a sound-insulating layer (10) of an elastic material, and where the matrix print head (1) and the slider (2) can be braced and/or clamped to each other in this region. This construction opposes a sound formation and sound propagation via the print head, the slider (2) and the rail guide (3) by body sound conduction onto frame parts of the printer by employing sound-insulation and sound absorption.

Abstract: The print substrate support (3) and longitudinal guides (4) for a print-head slider (7) are disposed in parallel at the invention printer. A controllable paper-guide drive motor (10) is furnished for the paper guide (9; 9a) and a drive motor (11) is furnished for the print-head slider (7). In order to be able to economically produce printers for different paper widths, and in order to eliminate problems of interfering radiation, a separated space (14) is furnished at the end of the paper guide (9; 9a) or respectively, of the longitudinal guide (4). At least one control-logic printed circuit board (15), an interface printed circuit board (16), the paper-guide drive motor (10) as well as the print-head-slider drive motor (11) are disposed in the separated enclosed space (14).

Abstract: In a printer, a drive motor, a drive roller arranged on the shaft of the motor, a reversal roller in spaced relation to the drive roller, and an elongated drive belt trained about the drive and reversal rollers form a tensioning device, the belt being fastened at its ends to a print-head carriage for selectively displacing the carriage in the forward and reverse directions along and relative to a printable substrate support roller or base. The reversal roller is carried in a carrier housing which movably and cooperatively engages a spring-loaded tensioning wedge for maintaining the elongated drive belt in a predetermined tensioned or stretched relation.

Abstract: The printer with a substrate support (1) is furnished with a layer structure in a print support cross-section (11). The layer structure comprises a metallic print bar (13), a vibration-attenuating damping layer (14), and a metallic intermediate layer (15) disposed sequentially in print element operation direction (12), where the intermediate layer (15) acts only functionally as "intermediate layer." In order to avoid a space-requiring and bulky layer structure of an insulating layer (16), neutralizing the frequencies of contacting components, the frequency-neutralizing insulating layer (16) is formed by elastic caps (18) at the ends (17a, 17b) of a unit, where the unit is formed by print bar (13), damping and absorbing layer (14), and intermediate layer (15). The elastic caps (18) can be slid into the recesses (19) of the printer side walls (20).

Abstract: The drive includes a cable attached to opposite sides of the print head carrying carriage, looping on one side in several loops around a drive drum, and on the other side around a deflection pulley. The deflection pulley is mounted on a spring-biased pivot lever to tension the cable in an adjustable manner. The drum is connected to the drive motor in a compact fashion by means of a belt drive.

Abstract: A circuit board arrangement that is for an electronic/electromechanical apparatus and that has a mechanically actuable switch for at least two different power line voltages includes a circuit board having a polygonal cutout therethrough, which defines a plurality of polygon sides. A plurality of contact surfaces on a first side of the circuit board is provided, each such contact surface being associated with a respective polygon side of the polygonal cutout. Each of the contact surfaces is connected to an electrical conductor of a power supply unit and is positioned such that a pair of contact surfaces opposite to each other with respect to the cutout correspond to one voltage. A contact spring extends into the cutout and has a pair of spring legs respectively contacting a pair of contact surfaces positioned opposite to each other with respect to the cutout.

Abstract: A device for the feeding or advancement of an edgeperforated paper web (1) in a dot-matrix printer or the like includes a pair of drive belts (3) transversely spaced apart proximate opposite transverse edges of the web, each belt carrying on its upper surface (6) a series of pins (7) for releasable engagement with the edge-disposed web perforations (11). To provide an increase in friction between the paper web (1) and the drive belts (3) during transport of the web, and thereby assure enhanced accuracy and precision in operatively advancing the web, a plurality of upstanding or outwardly-protruding projections (17, 17a, 17b, 17c) are defined on the upper belt surface (6). These projections are located at least in the flat sections (16) of the belt between adjacently or successively-disposed ones of the pins (7) and, in another form of the invention, additionally at and coincident with the locations of the pins (7) which interrupt the transversely-oriented projections.

Abstract: A mono color ink ribbon is held by a pivotable ribbon holder in front of a print head being moved along the platen, and the ribbon holder rides on a rail which has a raised center or central portion and lower ends, so that on a pass by the print head from one end to the other, the ribbon holder is moved up and down over a full cycle. This way, full use is made of the ribbon which is run in a Moebius loop in a cartridge.

Abstract: A device for the transport of multilayer, edge-perforated imprint-receiving substrates (8) takes into consideration a curve-shaped transport path (9), wherein a thrust tractor pair (5) is disposed in front and ahead of a substrate support (2), as seen in transport direction (10). Several friction roller pairs are following to the thrust tractor pair (5). In each case, a pulling force is transferrable by way of at least one friction roller. The multilayer imprint-receiving substrate (8) rests with its rear layer (8a) on the substrate support (2). A tearing of the edge perforations of the imprint-receiving substrate (8) as well as belly and bulge formations of one of the two layers (8a, 8b) is avoided by furnishing the push tractor (5) with a braking element (19) for the front layer (8b). A following first friction roller pair (11) rests with a driven friction roller (11a) at the front layer (8b).

Abstract: The impact and associated noise of matrix printers is attenuated by a laminated platen bar construction comprising a (steel) platen proper, a bonding adhesive layer, a brass bar and a resilient decoupling layer on the platen carrier.

Abstract: In a device for the paper transport of single sheets and/or continuous paper in office machines, in particular in matrix printers, there are provided in pairs and at least separately driven friction rolls (1, 2) which are disposed rotatably in side plates; the friction rolls exhibit a length to diameter ratio of from 30:1 to 50:1 and are therefore very long and very thin.In order to provide the friction force in a uniform manner over the entire length of the very long and thin friction rolls, it is disclosed that the positive running bending line (16) of a first feed roll (1) based on its support forces (14a, 14b) in the printer frame (15) and the negative running bending line (17) of a second friction feed roll (2) based on its support forces (14a, 14b) in the printer frame (15) are tuned to each other such that the two bending lines (16, 22) run approximately parallel.

Abstract: A device is disclosed for tensioning of a pulling element (1) of a printer and in particular of a matrix printer, for a back and forth motion of a part (5) or of a carriage includes a first deflection roller (11) and a second deflection roller (12). A wedge surface (15) is furnished, which upon increasing inclination (16) is slidable in a direction parallel to a frame surface (17) disposed perpendicular to the pulling direction (18) and which wedge is subjected to the force of a tension spring (22) such that the adjustable second deflection roller (12) serves the purpose of an increase of the tensioning force in the pulling element (1).

Abstract: The paper feeder incudes an upstream friction roller pair for single sheet feeding, a pushing tractor for endless sheet feeding, and a common downstream (behind the platen) friction roller pair. Each pair has one roller mounted on a pivot lever and the two levers linkedly held in a spring biased linkage such that consistently the downstream roller pair exert a smaller friction force while rotating at a higher speed.

Abstract: Multiple paper sources, including several single sheet channels and a tractor driven endless sheet channel, feed a common channel; the single sheets are friction roller driven upstream from the common channel. The common channel is curved and feeds past a flat platen off a downstream friction roller pair which however deflects the paper to hold it taut against the platen. The friction rollers and tractors are reversibly driven and the tractor is separately disconnected from the drive and through a sensor control sheets can be retracted from the platen.

Abstract: In a printer having a platen, a printhead carriage moving along the platen, the mounting of a multicolor band ribbon with ribbon case and of a ribbon guide is improved by pivoting one end of the ribbon casing to the frame, and one end of the guide to the carriage; two cams are mounted axially immobile on a shaft and against the ribbon case such that different portions of these cams depending upon the rotational position of the shaft determines the pivot position of the case to thereby place different color bands in between said print heads and said platen; the frame for the ribbon guide is held by another cam mounted for axial movement with said carriage but rotating with the shaft so that all cams rotate in synchronism.

Abstract: A ribbon cartridge may contain a single color ribbon or a multicolor ribbon, and is of wide U construction with a first pair of aligned (coaxial) pivot pins extending away from sides at locations therefrom remote from the legs of the U; a second pair of pins extends also from the sides and parallel to the first pair of pins; finally, a pair of support projections extend from the legs and also in opposite directions from the sides; the printer has two pivot mounts for receiving the pins of the first pair to thereby mount the cartridge, permitting pitch-like pivoting; in addition, the printer contains either (a) a second pair of mounts open from above for receiving the pins of the second pair, and thereby mounting the cartridge in a fixed position for single color printing, or (b) a cam shaft with at least one cam of different radial dimensions for engaging at least one of the projections such that upon turning of the cam a variable pivot-pitch is imparted upon the cartridge, the pins of the second pair being u

Abstract: Sound attenuation for a printer which includes impacting print elements and other movable noise producing parts being mounted to a frame and further including a biparted housing; the frame bottom having downwardly extending feet by means of which the printer rests on a support surface; the housing envelops the frame and is provided with openings through which the feet project without touching the print housing; the housing is floatingly suspended on said frame through a plurality of connections each of which includes pins integral with the frame and being circumscribed by an attenuating sleeve which is being connected to the frame by a locking cap seated on the respective pin for holding down the sleeve.