Abstract: A dense array of ink jets is achieved by a fanning-in of chambers to a linear array of orifices. The ends of the chambers remote from the orifices have actuation locations which are coupled to elongated transducers having axes of elongation which are parallel to the axes of ejection of droplets from the orifices.

Abstract: A dense array of ink jets is achieved by a fanning-in of chambers to a linear array of orifices. The ends of the chambers remote from the orifices have actuation locations which are coupled to elongated transducers having axes of elongation which are parallel to the axes of ejection of droplets from the orifices.

Abstract: A toner cartridge, the cartridge having a first and second section. A toner material is located in the first section and maintained in the first section by a gasket. The gasket comprises a flexible substrate having attached to one surface thereof, a sealing material. The gasket is inserted between the first and second sections such that the substrate is in contact with the first section and the sealing material is preferably in contact with the second section. When the gasket is removed from the toner cartridge, toner material present in the first section is allowed to pass into the second section and into operable contact with a toner carrying apparatus operably connected to the second section of the toner cartridge.

Abstract: An improved ribbon shield for use with a ribbon cassette in a printer. The shield snaps into the front of a ribbon cassette so as to cover an exposed portion of ribbon and prevent the smudging or wicking of ink onto a printing medium. The ribbon shield includes an elongated strip of flexible material such as polypropylene having a central aperture to enable the ribbon to pass through it for printing purposes. The shield includes a lower curved lead-in portion to accommodate paper motion past the cassette. The shield is held within the ribbon cassette in a flexible state. The flexed portion of the shield contacts the printing medium and forces it into close contact with the platen. Improved performance can be obtained by providing spacing ridges in the form of rings which surround the aperture.

Abstract: A method for driving stepping motors, typically used in digital hard copy printers, can be employed wherein the phased stator coils of the stepping motor are energized in an overlapping relationship. In addition, the voltage or current applied to the stator coils in a stepping motor may be driven in a pulsed manner such that certain portions of the energized duration are characterized by a higher driving current or voltage. By virtue of the simultaneous activation of the adjacent phases of the stator coils, quasi-equilibrium positions may be created between the equilibrium positions in a stepping motor with the result that a smoother and more uniform angular accelerations and decelerations can be obtained. Circuitry conducive to a digital application to practice the method of the present invention employs a multiple bit shift register driven by a decoder and which in turn drives a plurality of operational amplifiers. Another operational amplifier coupled to the decoder provides a controlled current source.

Abstract: A platen gap adjuster for a printer utilizes a shaft along which the print head carriage slides during printing of each line. The shaft is eccentrically mounted by means of unitary, offset spindles the common axis of which is parallel to but spaced from the shaft axis. By rotating the shaft about the common spindle axis, the carriage and print head will be moved transversely of the shaft, thereby adjusting the gap between the print head and platen without impairing the longitudinal sliding motion of the carriage.

Abstract: Apparatus for stacking fan-folded paper including an oscillating chute through which paper received by the stacker from a printer passes toward a pedestal on which the paper is to be stacked. The stacker receives line strobe signals from the printer indicative of the rate at which paper is fed by the printer to the stacker. The line strobe signals control the rate of oscillation of the chute between two extreme positions. The distance between the two positions defines the oscillation stroke which is determined by means of a manually-operable selector to be a function of the form length of the paper to be stacked. The paper is stacked on a pedestal which is incrementally movable between top and bottom positions. A stack sensor is provided which senses the top of the stack and causes the pedestal to move toward the bottom position so as to maintain the distance between the chute and the top of the stack relatively constant.

Abstract: A hammer bank assembly useful in high speed, moving type, impact printers of the kind generally employed in data processing systems. The assembly is comprised of a mounting structure supporting a plurality of aligned hammer modules and a plurality of aligned magnet modules. The mounting structure includes a rigid cylindrical tube and a plurality of fastening members disposed therealong. Each hammer module includes multiple hammers resiliently mounted on a common foot member. Each hammer is comprised of an impact tip carried on a rigid coil structure. Each hammer module foot member has a recess of substantially semicircular cross section dimensioned to conform to the periphery of the rigid tube. A plurality of identical hammer modules are mounted on the rigid tube with each foot member being secured to a different fastening member and with the tube engaging each foot member in the recess thereof.