Abstract: Various configurations and applications of traveling wave grids are disclosed. Systems for transporting particles to feed apertures, and/or for transporting particles from storage reservoirs are described. The systems are particularly useful for transporting toner particles in printing systems.

Abstract: A transfer belt apparatus, system and method are provided to prevent image blooming. For example, an ink jet printing apparatus may include a grounded print head, a counter-electrode opposite the ground print head, and a bi-layer transfer belt provided between a print head and a counter-electrode and at least partially supported by two or more transfer bias rollers. A method may include applying a voltage between a print head and a counter-electrode to accelerate ink drops coming out of the print head toward a transfer belt, and evacuating charge accumulated on the transfer belt with a time constant smaller than a drop ejection frequency of the print head.

Abstract: A toner gating apparatus for supplying toner through an aperture to a gas channel having a propellant stream. The toner gating apparatus has a traveling wave grid having electrodes. A first gating electrode is located proximate a first side of the aperture. A second gating electrode is located proximate a second side of the aperture. A third gating electrode is located in the gas channel. A first voltage source having a first phase is connected to both the first gating electrode and a first electrode of the travelling wave grid. A second voltage source having a second phase is connected to both the second gating electrode and a second electrode of the travelling wave grid. A third voltage source having a third phase is connected to both the third gating electrode and a third electrode of the travelling wave grid.

Abstract: A magnetic spring, or a spring and motor combination, providing a linear spring force characteristic in each direction from a neutral position, in which the spring action may occur for any desired coordinate of a typical orthogonal coordinate system. A set of magnets are disposed, preferably symmetrically about a coordinate axis, poled orthogonally to the desired force direction. A second set of magnets, respectively poled opposite the first set, are arranged on the sprung article. The magnets of one of the sets are spaced a greater distance apart than those of the other, such that an end magnet from each set forms a pair having preferably planar faces parallel to the direction of spring force, the faces being offset so that in a neutral position the outer edge of the closer spaced magnet set is aligned with the inner edge of the greater spaced magnet set.

Abstract: A control system for a thermal transfer device in which a selected image is transferred from a strip of color carrying ribbon to a strip of image carrying tape and precise alignment between adjacent columns of vertical print is achieved by monitoring and controlling the rotational speed of the drive means for the thermal transfer device and activating the printing of each column of pixel data based upon positional information of the tape and ribbon determined in relation to the rotational speed of the drive means so that each column of pixel data is of a uniform and consistent width.

Abstract: An ultrasonic sector scanner includes first and second magnetizable stators spaced on a longitudinal axis. First and second rotors are provided in the gaps between the end faces of the first and second stators, respectively. The rotors have tapered surfaces spaced from the end faces of the stators to form gaps therebetween. The gaps between the first rotor and the end face of the first stator decrease as the rotor rotates in a first direction. The gaps between the second rotor and the end faces of the second stator decrease as the rotors rotate in a second direction opposite the first direction. An ultrasonic transducer is connected to the rotors and arranged to be rotatable with the rotors. A servo-control system is provided to cause the rotor/transducer assembly to rotate according to a prescribed reference signal.The ultrasonic sector scanner has a cover assembly in which a flexible membrane is provided with ribs which engage grooves in the wall of the housing.

Abstract: A vibration balancing arrangement utilizing a counterbalance mass oscillating at a frequency near its resonant frequency. Resonance is obtained by a gas spring, in which the length of the compression region for the gas is variable to vary the resonant frequency by adjusting the center point of the oscillation of the counterbalance mass.

Abstract: An ultrasonic scanning apparatus includes a rotor, first and second electromagnetic stators, and an ultrasonic transducer mounted on the rotor. Each electromagnetic stator has two curved pole faces arranged opposite pole faces on the rotor. The electromagnetic stators are arranged on opposite sides of the axis of rotation of the rotor. The stator pole faces are tapered such that on rotation of the rotor in one direction, the gaps between the rotor and a first stator decrease while the gaps between the rotor and the other stator increase. On rotation of the rotor in the opposite direction, the gaps between the rotor and the first stator increase and the gaps between the rotor and the second stator decrease. Means are provided for alternately energizing the first and second electromagnetic stators to cause the rotor to oscillate about the axis of rotation.