Abstract: A recording apparatus includes a media support adapted to receive recording media. One or more guide members are attached to the support and extend along a first direction substantially perpendicular to a first neutral axis and a second neutral axis associated with an assemblage comprising at least the support and the guide members. A carriage is adapted to move along the guide members and operable for moving a recording head along a path relative to the media support while forming an image on the recording media. One or more thermal compensation members is fixedly attached to the support to reduce distortions of the assemblage about both the first neutral axis. The second neutral axis, the distortions arise from a difference in thermal expansion between the each of the one or more guide members and the support.

Abstract: A self-compensating tensioner, particularly a self-compensating tensioner for use in a folder of a web offset printing press, includes a plurality of rollers designed to tension tapes. Each roller is mounted on a tensioner arm. The tensioner arms are mounted on a rotatable shaft via one-way clutches with a weight attached to each tensioner arm so that the center of mass of the tensioner arm is offset from the rotatable shaft. The force of gravity may therefore rotate the tensioner arm about the shaft, applying a minimum tension to the tape through the roller. A lever arm is connected to the shaft through an engagement clutch, with an actuator connected to the lever arm. When the actuator and the engagement clutch are activated, the lever arm can apply a torque to the tensioner arms through the shaft, thereby increasing the tension in the tapes to a working level.

Abstract: A printer in which print densities of print heads can be adjusted simply and rapidly and set to have an optimum impact force, and a method of adjusting a print density are provided. Concretely, print density patterns which can be set at regular steps toward the high and low density sides of a predetermined density are generated. On the basis of the print density patterns, printing is conducted on a recording medium. A pattern in which a desired print density appears is selected and the print densities of the print heads are absolutely or relatively adjusted.

Abstract: A dot matrix line printer includes a counter that counts a number of print actions performed by each of a plurality of print actuators. The accumulated number of print actions can be compared to a reference number of print actions representative of a useful print actuator life for each print actuator. The counting process is performed based on the horizontal dot density, the number of print actuators, the number of bytes of dot data that each of the actuators is required to process, etc. This structure and method enable maximized use of print actuators regardless of location along the actuator array.

Abstract: A molded plastic printer carriage mountable in the printer on a slider rod uses a pair of spaced sintered bronze bushings and a spring biased preload pad intermediate the bushings which engages the slider rod to compensate for and minimize rocking of the carriage during rapid movement thereof during printing without requiring expensively machined slider rods or close tolerance bushings.

Abstract: A molded plastic printer carriage mountable in the printer on a slider rod uses a pair of spaced sintered bronze bushings and a spring biased preload pad intermediate the bushings which engages the slider rod to compensate for and minimize rocking of the carriage during rapid movement thereof during printing without requiring expensively machined slider rods or close tolerance bushings.

Abstract: A molded plastic printer carriage mountable in the printer on a pair of slider rods uses a pair of spaced front bushings and single rear bushing positioned on a line intermediate the two front bushings. The rear bushing is eccentricly spring biased in a direction away from the front bushings and each bushing has two line contacts with the slider rod on which it is mounted, the first of the line contacts being at the top of the bushing and the second being on the side of the bushing substantially facing the opposite slider rod. The eccentric spring biasing and the two line contact configuration of the bushings prevents rotation of the carriage around the slider rods during rapid movement thereof during printing.

Abstract: A dot printer device is disclosed, in which in order to print a horizontal ruled line, paper feed data for placing the head pin of a printing head at a predetermined position on a printing paper, dot pin data indicative of a dot pin specified on the basis of a predetermined rotation of dot pins for printing the horizontal ruled line, and paper feed data indicative of how much the printing paper is to be moved in accordance with the predetermined rotation of dot pins after the horizontal ruled line has been printed by the specified dot pin, are sent from a control unit to a printing unit.

Abstract: In a line printer, an integrated meter package developing a clock incorporates a microprocessor receiving a line printed signal, power on voltage, and a preset ribbon exhaust count in order to compute in reference to the clock, and selectively display on an alphanumeric display panel, the total the lines printed, total on hours, total print hours, preset ribbon exhaust count, and number of print lines remaining until exhaustion of the ribbon. The microprocessor stores accumulated values to a non-volatile electrically programmable memory upon receipt of a power going down signal warning of incipient power off. The microprogrammed control is adaptable to maintain general maintenance and fault histories and periods.

Abstract: A center-to-center distance measuring device for measuring the exact spacing between print solenoids. The devie uses a test block having a top surface and a bottom surface which are parallel. The top surface has first and second bevel surfaces which are parallel to each other, extend from the top surface towards the bottom surface and are spaced apart at a predetermined distance. The print solenoids are positioned perpendicularly to the top surface of the test block such that the print wires of the print solenoids impact against the test block when energized. The displacement of the print wires from the solenoids is used to determine the center-to-center spacing as the print wires impact against the bevel surfaces as the test block is moved.

Abstract: An aging correction system for an LED array in a printer, in which each LED can be energized during a variable time and in which a light sensor, with which the relative light-output of each LED can be measured and compared with earlier measured values, is disposed near the array, and in which on the basis of these measured values a new correction value is determined.

Abstract: A printer, which can adjust the attached position of the print hammer without a device specifically provided for the position-adjustment, is provided with an adjustment mode in addition to a normal printing mode. In the adjustment mode, a predetermined type on the type wheel is set into a predetermined printing position by the rotation of the type wheel, in the same manner as in the normal printing mode. Accordingly the attached position of the print hammer is adjusted easily to establish accurate contact between the hammer and the type in the printing position.

Abstract: In a method for operating a serial dot matrix printer having a print head that is reciprocated along a first direction and stopped for performing bi-directional printing on a medium that is moved in a second direction orthogonal to the first direction, correction amounts for correcting the bi-directional printing alignment are stored in a memory device. The desire correction amount is then selected and stored in a battery-backed-up memory. The bi-directional printing then is performed using the desired correction amount stored in the battery-backed-up memory.

Abstract: A dot printer apparatus having a recording head with a plurality of recording elements such as LED's, etc. Counting means is provided to count the number of prior activations of each recording element during a past production run. In one embodiment, the recording elements are enabled during a nonproduction run to age those recording elements to compensate for their relative lack of use during the last production run. In another embodiment, age compensation is provided during the next production run with the on-times to the recording elements adjusted in accordance with correction signals related to the counting of prior activations of each of the recording elements during the last production run.

Abstract: Wear on the elements (5) of a printhead (3) is spread by shifting the region of use of the printhead line by line. Font (13) provides information as to whether any character in a line employs the upper three pels or the bottom three pels of a line. For each line which can be printed from different shift positions of the printhead, selection logic controls paper feed (15) to index platen (9) to the least used of a shifted position of printhead. Only those electrodes over the print line in each shifted position are used for printing. This distributes wear without requiring any special ribbon feed. The three pel height is at least as wide as the serifs on most characters, which avoids some electrodes being used for the serifs of given characters in more than one shift position.

Abstract: A device for monitoring and compensating for changes in the flight time of the print hammers of impact printers is disclosed. The flight time of the respectively monitored hammer is calculated from the elapsed time between the moment of firing of a hammer and the moment of impact of the print type carrier against the impact platen. In order to ensure automatic self-adjustment of all print hammers in predetermined test cycles, without the actual printing process itself being affected, and without there being any test imprints on the record carrier, the print type carrier includes, in addition to the standard print types, an additional test type. The impact surface area of the test type is large enough such that no visible imprint is made upon its impact on the record carrier because of the low impact pressure.

Abstract: A method is provided for adjusting to an original predetermined value the natural frequency of the carrier load of a processor controlled stepper motor driving said carrier through a belt and pulley arrangement. The adjustment is performed by having the microprocessor move said carrier back and forth repetitively, at a rate based on the original natural frequency value and by adjusting the belt tension for obtaining maximum amplitude vibrations of the carrier load.

Abstract: A wire matrix print head having print wires subject to wear at their printing ends are biased by return springs against one side of one end of armatures, the other sides of which bear against a gap adjusting ring. The other end of each of the armatures is spaced by a predetermined gap from the pole piece of associated electromagnets which, when energized, drive the armatures about pivots intermediate the ends of the armature against the bias of the return springs. The ends of the armatures are formed with a step on the side initially placed in contact with the drive end of a print wire so that when the print wires are worn the armatures can be flipped over to present the unstepped side in contact with a drive wire with the result that upon movement of the adjusting ring to restore the gap between the armature and pole piece the print wires are pushed to a rest position closer to the printing plane by the depth of the step.