Abstract: A serial impact printer of the type utilizing a dot matrix print head is specifically adaptable for use as a calculator or adding machine and is characterized by utilizing a common drive source to advance the print head across the paper, advance the paper between printing operations, and selectively advance the print ribbon between the ribbon supply spool and takeup spool. An improved paper-advancing means has been devised which operates in close correlation with the print head drive member to provide a relatively high speed, simplified and inexpensive printer unit; and the ribbon supply spools are so constructed and arranged as to be interchangeable and to permit direct drive through a spool-engaging member on the print head whereby to advance the ribbon in direct response to print head travel.

Abstract: A matrix printer which is specifically adaptable for printing and the like is characterized by having a stationary print head containing a plurality of print wires which are arranged in a single row extending transversely of the direction of travel of a relatively heavy paper stock. The paper is advanced at a substantially constant rate of speed along the guide path and signals are generated in response to that advancement to activate selected ones of the print wires in the row so as to form dot-like impressions in the paper, line-by-line, as it is advanced past the print head. The density or spacing of the wires coupled with the printing speed is such that designs, alphanumeric characters, together with coded information, may be impressed upon the paper as it is continuously advanced past the print head, the code providing a means of verification of the information printed as well as to signal the end of the printing operation for each ticket.

Abstract: In a print head assembly for calculators and the like, the print head is reversibly driven in a print and return direction transversely of the direction of advancement of the recording medium by a drum segment having a cam drive in the form of an endless helical groove which extends along a cylindrical surface of revolution between opposite ends of a drive axle mounted in driving relation to the print head so that rotation of the drum will impart translational movement to the print head through a suitable drive member engaged by the helical groove at a preselected rate of speed both in the print and return direction.

Abstract: A lightweight, extremely compact printer apparatus has a constant speed drive which imparts reversible, translatory motion to a print head; and as the print head is advanced with respect to a platen imparts a direct mechanical drive to a paper advancing roller in order to advance paper from a feed roll line by line between printing operations. In turn, advancement of the paper or other recording medium from the paper roll drives a print ribbon supply holder to advance a print ribbon across the platen in front of the paper. The power requirements and size of the apparatus are substantially reduced to the extent that the apparatus is of a size corresponding to hand held calculator printers, since the movement of each element is utilized to drive another element successively from the print head carrier, paper advancement roller, paper roll to the print ribbon in close correlation to one another during each print cycle.

Abstract: A serial impact printer of the type utilizing a dot matrix print head is specifically adaptable for use as a calculator or adding machine and is characterized by utilizing a common drive source to advance the print head across the paper, advance the paper between printing operations, and selectively advance the print ribbon between the ribbon supply spool and takeup spool. An improved paper-advancing means has been devised which operates in close correlation with the print head drive member to provide a relatively high speed, simplified and inexpensive printer unit; and the ribbon supply spools are so constructed and arranged as to be interchangeable and to permit direct drive through a spool-engaging member on the print head whereby to advance the ribbon in direct response to print head travel.

Abstract: A wire matrix print head for a dot matrix printer employs a plurality of electromagnetically actuated print wires converging forwardly through a wire guide member for termination at their leading ends in confronting and adjacent relation to the print medium. The trailing ends of the print wires are mounted within electromagnetic actuators for movement in a lengthwise direction to cause their leadings ends to be driven into the print medium to form a series of even impressions or dots thereon, the print wires being displaced at equal included angles between adjacent print wires. The wires diverge in different directions along equal radii of curvature preferably corresponding to their elastic curves from their leadings ends toward the trailing ends whereby to minimize frictional surface engagement in supporting the wires for movement into the print medium under an equal degree of force to assure uniform impressions or dots in forming each character or symbol.

Abstract: A serial impact printer of the type utilizing a dot matrix print head is specifically adaptable for use as a calculator or adding machine and is characterized by utilizing a common drive source to advance the print head across the paper, advance the paper between printing operations, and selectively advance the print ribbon between the ribbon supply spool and takeup spool. An improved paper-advancing means has been devised which operates in close correlation with the print head drive member to provide a relatively high speed, simplified and inexpensive printer unit; and the ribbon supply spools are so constructed and arranged as to be interchangeable and to permit direct drive through a spool-engaging member on the print head whereby to advance the ribbon in direct response to print head travel.

Abstract: A system enables selective control of instantaneous motor armature position and, thus, the corresponding position of one or more elements driven by the motor. As utilized in a high speed printer, the system governs positioning of a printhead, enabling high speed movement of the latter from one location to the next and yet bringing it to a complete stop exactly at a selected or desired location. Additionally, the system enables position control with respect to movement over different predetermined distances such as, in the printing embodiment, of character or word spacings, carriage returns, tab sets and vertical indexing. Operationally, armature position-representative pulses are counted and analyzed to determine during acceleration when one desired position has been reached and, during subsequent deceleration, to determine when zero movement has been reached.