Abstract: A striker assembly for operating the printing hammer in a high speed impact-type line printer. The assembly is a simple, low cost unit having a minimum of components. The striker body is of one-piece molded construction having a head and neck portion. An armature backstop is carried in the head portion which may be externally adjusted for printer character alignment during operation of the line printer by exerting pressure on the head portion with resulting flexure of the neck. The backstop is self-aligning during such adjustment. The striker assembly is mounted to permit adjustment of printed character density during operation of the line printer.

Abstract: A cursive writing type cathode ray tube (CRT) display system in which the vertical size of the characters are increased by an input command from a keyboard and central processing unit (CPU). The CRT has both electrostatic and magnetic deflection systems with the magnetic deflection producing a raster in which each horizontal scan is electrostatically deflected to write characters on the screen. The characters are formed from stored digital codes selected by commands from the CPU. Digital to analog (D/A) converters produce analog deflection signals to produce a set of multiple strokes to form a character and to produce analog voltages for controlling the brightness of the stroke. Digital commands from the CPU are generated to increase or decrease the magnitudes of the various analog signals from the D/A converters when changing the vertical character size.

Abstract: A cam drive system having parallel input and output shafts and means for rotating the input shaft includes a plurality of cams coupled at intervals around the periphery of the input shaft. Each cam utilizes a camming surface which incorporates a radially outwardly sweeping step section and a constant radius dwell section positioned adjacent to each step section. A plurality of cam followers are coupled at intervals around the periphery of the output shaft. Each cam follower is aligned to engage a single one of the cams. The present invention converts the continuous rotation of the input shaft into intermittant displacements of the output shaft.

Abstract: A high speed printer elevator control mechanism includes an elevator frame having a paper guide chute for guiding paper into a bin and rides up and down in the bin responsive to an electric motor drive. The elevator moves a pre-determined distance above the paper being stacked in the bin responsive to control signals initiated by counting the paper being stacked in the bin. A pair of paper control strips or flappers are mounted to the elevator frame for guiding the paper in the bin and a switch is mounted to the elevator frame adjacent one of the flappers so that the switch is actuated by the movement of the paper control strip to generate a signal by each movement thereof. The signals are counted by the microprocessor which initiates the command to move the elevator.

Abstract: A character generator produces highly accurate electronic reproductions of characters of any chosen style on the screen of a CRT by simultaneously controlling the orientation, length and intensity of the strokes formed by the electron beam of the CRT. The character generator is coupled to an input source which periodically generates a character address signal representative of a selected character. A read only memory contains a plurality of multi-byte microprograms each located at a predetermined address. Twelve eight-bit bytes constitute a single microprogram which defines a single character. A single byte of a microprogram defines a single stroke of a character. A first three-bit element of each byte fully defines the magnitude and polarity of the X component of the stroke, while a second three-bit element of the byte defines the magnitude and polarity of the Y component of the stroke. The remaining two-bit element of the byte designates one of four available electron beam intensity levels.

Abstract: An anti-fold apparatus for high speed printers to prevent the folding or creasing of a printer ribbon riding over rollers. The rollers each have spiral angular serrations thereon, and are mounted in two pairs with each roller in a pair having one end abutting the end of the other, and each being mounted at an angle to the elongated center axis of the other, so that a printer ribbon rolling thereon is directed away from the abutting ends of each pair of rollers to prevent creasing therein. A linkage connects the two pairs of rollers at their abutting ends for shifting the angular position of each pair simultaneously between first slanted positions, when the ribbon is moving in one direction, and second slanted positions, when the ribbon is moving in the reverse direction. The linkage is actuated by solenoids, actuated by the reversing of the ribbon.

Abstract: A high speed printer is provided having a plurality of aligned hammer assemblies for directing hammers at a moving character band for printing characters responsive to the hammer's driving against the character band. The hammer assembly has a striker arm pivotly mounted to a striker assembly frame and which acts as an armature when driven by a pair of magnets. The magnets are attached to the striker assembly frame on opposite sides of the striker arm and on opposite sides of the pivot point for the striker arm so that simultaneously actuating both magnets pulls the striker arm for actuating the hammer. Each magnet has a single coil, with one of the magnets having a reverse polarity from each adjacent magnet on an adjacent assembly, while the other magnet has the same polarity to avoid cross-talk and to increase the speed of the printer.

Abstract: A card reader for reading data cards of the type having columns of machine-readable information thereon and transmitting data outputs representative of this information to an interface, includes a read station for sensing the information in each column and generating corresponding data outputs. A latching circuit receives data outputs from the sensing means and transmits the data outputs to the interface responsive to a strobing signal. A timing wheel is employed to detect the velocity of the cards during transport through the read station to provide an output proportional to velocity. A train of pulses is generated for each column responsive to the velocity output, and the period of the pulse train is adjusted to compensate for increases or decreases in the velocity of the card through the read station, by employing a phase-locked loop circuit.