Abstract: A paper stacker includes adjustable sides to receive paper passively of different widths. The uppermost ends of the sides are flared to avoid paper encountering these ends, permitting the received paper to slide down between the sides to settle on a bottom surface without assistance. Each of the sides has a portion cut away to permit grasping a paper stack for removal. A trapezoidal platform is located on the bottom between the sides and has a friction material on a substantially flat upper surface to prevent paper slippage.

Abstract: An impact printing device for printing postal bar code patterns on an information carrier. The patterns are a combination of parallel tall and short bars separated by spaces. The type elements are attached to a movable type carrier, each element comprised of pairs of vertical bars having different stroke lengths but equal widths. Additionally these elements contain overscored and/or underscored horizontal bars, that when printed appear outside the postal bar code clear space. This produces print elements that have nearly equal area and in turn produce printed characters of uniform stroke widths that are easily read by the U.S. Postal Service electronic readers.

Abstract: Tractor drives of a high speed printer move a length of continuous-form paper longitudinally up from a box of fanfold stacked paper, through a print mechanism and downward to refold onto a fanfold stack. A set of bead or link chains hang vertically from the printer on each respective major side of the descending paper. The chains are positioned to interact with the folding paper. The chains swing against the paper to aid in creasing the paper at the folds in the proper fanfold direction. One or more chains have pendants attached at the chain's lower swinging end. The pendants are sufficiently long, stiff and light weight to prevent the lower ends of the chains from getting caught in the refolding stack of paper which could lead to jamming the travel of paper through the tractor drives. Preferably, the pendants are produced from 7 inch long segments of approximately 25 mil.

Abstract: A printer apparatus has a frame member supporting an endless revolving type band in alignment with a row of print hammers with a gap therebetween. Ribbon spools with ribbon wound thereon are rotatably supported in spool housings at either end and on opposite sides of the frame member. The spool housings each have a receptacle portion and a cover portion which enclose the spool. A gap in the spool houses enables the ribbon to extend between the housing and through the gap. The ink ribbon is guided through the gap in parallel with the row of hammers and at an angle to the print line by a set of guide pins on the cover of one spool housing and a set set of guide pins mounted on the frame member in proximity with the other spool housing. Both sets of guide pins engage the same side of the ink ribbon in a manner whereby touching the ribbon is not required to install or remove the ribbon from the printer apparatus.

Abstract: An impact printing device for printing bar code patterns on an information carrier, the patterns including a combination of parallel thin and wide bars separated by spaces wherein the wide bars can have an imprint width which is a multiple of the thin bars, comprising a movable type carrier, a plurality of bar code type elements on said type carrier, the bar code type elements including first type elements having a pair of imprint forming parallel thin bars and second type elements having a single imprint forming thick bar, and a plurality of print hammers each defining a print position of a print line and each operable selectively to successively impact combinations of the first and second type elements at the same print position to form completed bar code imprints at the print position having a wide bar imprint with a width greater than the single thick bars of the second type elements.

Abstract: High speed impact line printers comprise a continuously moving type carrier, such as an endless belt or band having engraved type characters movable at constant speed parallel to a row of print hammers. A print medium such as a continuous paper web and an ink ribbon are located between the hammers and the type carrier. The hammers are uniformly spaced parallel with the type carrier to define a print line. The spacing of the hammers corresponds to the desired spacing of the printed characters when printed and generally has one print hammer for each print position. An interposer member located between the print hammers and the print paper web enables certain characters such as vertical or horizontal bars of bar code type can be printed in the region of the clearance gaps between hammers.

Abstract: The disclosure describes in detail one of the most serious problems in connection with maintaining the operating life of print hammers at the high speeds of todays printers. Also described in detail is a structural arrangement to solve this problem without involving a major redesign of a print hammer module. A significant aspect of this solution is that a high speed print hammer is kept out of contact with structure that serves as a reservoir for the pivot pin lubricant.

Abstract: Damping apparatus within an actuator device in which a backstop is supported on one portion of a dual cantilever to match the movement of the impacting actuator to reduce wear and provide positive restoration of initial position, wherein the backstop-supporting cantilever portion is embedded in energy-absorbing elastomeric material that is symmetrically confined to shorten settling time of the actuator and remain unaffected by temperature changes.

Abstract: A heat exchange system for an electromagnetically operated print hammer of a print hammer bank provides internal and external heat transfer for the operating windings. A non-magnetic metal bobbin of the heat exchange system provides conductive transfer of heat from the interior of the operating winding to the magnetic core. Flat parallel plates of magnetic material are attached to the sides of the operating winding for external heat transfer and magnetic flux shielding. The plates may have multiple laminations having different saturation and permeability characteristics.

Abstract: An electro-magnetic print hammer comprises a single magnetic hammer element in which an impact mass is coupled to a pivotted armature by flexible stem. The hammer-stem has (N+1/2) periods of oscillation at its resonant frequency during the free flight time of the hammer mass. A permanent magnet with a strong magnetic force which decays rapidly with distance holds the hammer element fixed upon motion of the armature until the armature torque exceeds the magnet holding force to cause the hammer mass to break loose with a snap action. Stop means prevents armature impacts with the operating pole piece of a stator core. The visco-elasticity of the armature stop matches the rebound characteristics of the print medium when impacted by the hammer mass.

Abstract: Method of recording with a stream of marking fluid drops in which a predetermined plurality of successively formed drops in a stream each have the same electrical charge induced therein so that, when subsequently subjected to an electrostatic field, all drops of one commonly charged plurality will impact a record member at approximately the same spot. Drop charges are induced therein by asynchronously applied charging signal levels, each having a duration which is a function of the drop formation frequency and equal to at least two drop periods.