Abstract: A charge plate fabrication process provides a catcher/charge plate assembly having improved manufacturability. The fabrication process includes the steps of providing a catcher, including a catch pan, and providing a ceramic charge plate, the charge plate having an electrode face. The charge plate electrode face is prelapped to a uniform negative angle before assembling the charge plate and the catcher in a fixture. The assembled catcher and charge plate are then bonded in the fixture.

Abstract: Ink concentration in a system is maintained regardless of the duty cycle under which the system is operating. In an ink jet system, a print head receives ink from the main ink supply and forms continuous drops. The drops needed for printing to form the desired image are selected from the continuously formed drops. Based on the selection, a count signal is produced indicative of the number of drops printed. An ink level sensor in the main ink reservoir generates a low ink level signal when ink in the reservoir reaches a predetermined low level, the difference between a normal level and the low level corresponding to a predetermined cycle volume. A fluid connection selectively allows flow into the main ink reservoir from either the external supply of ink or the external supply of ink replenisher.

Abstract: A catcher for an ink jet print head is provided with locating features in the catcher throat to positively locate a catcher screen that serves to wick caught ink into the catcher throat, and a screen construction that resists compression of the screen without adversely affecting the ink flow in the catcher throat.

Abstract: A system for controlling the formation of droplets in a fluid stream includes a continuously flowing fluid stream through a droplet generator. The system further includes both a sinusoidal drive voltage at a predetermined frequency and a plurality of piezo electric crystals for causing the droplet generator to resonate and inducing a series of uniformly sized droplets to separate at regular intervals from the droplet generator. Finally, the system includes a drive signal for adjusting to the resonance of the droplet generator to control the formation of the droplets. The drive signal is applied to the crystals by a digital phase lock loop.

Abstract: A print engine module for use with a remote print head is an integral unit having removable drawers and permanently installed drawers, each drawer containing a component of an ink jet printer. The removable drawers contain a fluid system unit, a charge power unit, a power supply unit, and a card cage unit. Also within the print engine module are two fixed components that are in drawers permanently attached to the print engine module cabinet. The permanent units include power distribution unit and a computer unit.

Abstract: Connections to a charge plate in an ink jet print head are made using anisotropic conductive material. Reliable, high yield connections approaching 200 connections per inch are achieved.

Abstract: An apparatus for accurately controlling gas fuel flow to a combustion device is provided to control gas flow to a burner of the combustion device. A variable orifice solenoid operated valve serves as a control element. The valve includes a poppet having a fixed control surface at an end received in an insert element having a variable control surface. The poppet has a plurality of positions within the insert element, including a full open position and a full closed position. Maximum fuel flow is measured in the full open position and minimum fuel flow is measured in the full closed position. Intermediate partially open positions are adjustable by a signal of an electronic controller connected to the solenoid valve operating as a function of actual and desired temperature of the combustion device.

Abstract: An apparatus and method allow for assembly of a print head apparatus for an ink jet printer. The apparatus comprises control capability for controlling the flow of fluid to the droplet generator and for controlling transfer of data to the droplet charging and collecting element. The control capability for controlling transfer of data to the droplet charging and collecting element is a motherboard containing various elements. The motherboard includes a microcontroller and fiber optics for receiving data and control signals and providing the signals to an input buffer. A RAM provides data memory, and a latch and shift register latch and shift the data from the RAM. A high voltage driver receive data from the latch and shift register. A control state machine communicates with the microcontroller, for handling generation of all control signals for the input buffer, the RAM, and the latch and shift register.

Abstract: An ink jet ink composition comprises a liquid vehicle, a dye, and an N-hydroxyalkyl branched polyethyleneimine polymer or an N-hydroxyalkyl diphenylguanidine substituted at about 80% of the available nitrogens. The dye in this ink jet composition decreases the solubility of the ink and, therefore, can be used to formulate waterfast inks for ink jet printers.

Abstract: An electronic system is used with one or more digital clocks. The electronic system comprises a two-wire module, attached to the digital clock, for allowing each digital clock to be run and reset to the correct time. A master clock controls a DC supply voltage applied to the two-wire module. The DC supply voltage keeps the digital clock in synchronization with the master clock. Interrupting the DC supply voltage and subsequently reapplying the DC supply voltage causes the two-wire module to set the digital clock to a predetermined time. Reversing polarity of the DC supply voltage for a calibrated time period electronically activates the two-wire module to reset the digital clock to the correct time.

Abstract: The present invention constitutes in an ink jet printing apparatus, an improved ink replenishment system. An ink supply housing of the improved ink replenishment system includes a pair of opposed side walls having a plurality of attachments spaced in respective opposing vertical columns and detachable detents coupled to one of the attachments. An attachable ink supply conduit is associated an associated ink supply module includes a container of ink having an ink egress constructed to attach to the conduit, and a housing having bottom and side wall members supporting the container. The side walls have a vertical edge with a plurality of removable sections located in spaced relations corresponding to the column spacing of the attachments and sized to correspond to the detents. Only an ink supply module having proper sections removed can be moved into the housing to an extent sufficient for its egress to connect to the supply conduit.

Abstract: A system and method for emptying a refill container used in a continuous ink jet fluid system reduces the amount of ink left in the refill container and eliminates adverse effects in the event that air enters the fluid system through the refill apparatus. The system for emptying the container includes a system vacuum and a refill container. A bi-directional path is provided between the system vacuum and the refill container. The air is then removed from the refill container while maintaining the system vacuum within a predetermined range.

Abstract: A stimulator for a continuous ink jet print head is fabricated by providing a surface roughness of between 100 and 200 microinches on the surface of the stimulator body and attaching a piezoelectric transducer strip to the body using an acrylic cement having a viscosity of between 2 and 100 centipois. The resulting stimulator exhibits improved lifetime with acceptable acoustic properties.

Abstract: A fluid system is usable with a four inch print head of a continuous ink jet printer. The fluid system controls all critical ink jet functions. The fluid functions electronically feedback-controlled by the fluid system include pressure control at the print head. The fluid system also controls ink temperature during startup and ink concentration. Finally, the fluid system controls vacuum level.

Abstract: An ink jet printing device has a drop generator for producing continuous streams of ink drops from at least one orifice and further has stimulation control electronics for maintaining desired stimulation conditions in response to a feedback from the drop generator. First and second feedback transducers measure the stimulation amplitude in the drop generator and generate feedback output signals in response to the stimulation. The feedback output signals are approximately equal in magnitude and opposite in sign to each other when the stimulation amplitude in the drop generator is a desired stimulation mode. An amplifier, whose inputs are the feedback output signals, provides an amplifier output signal to the stimulation control electronics which is the difference between the two feedback output signals.

Abstract: A recording liquid for ink-jet recording comprising coloring matter, which is an image-forming component, and a liquid medium for dissolving the coloring matter therein. The liquid medium is ethanol and the coloring matter is a dye represented by the following general formula (A): ##STR1## or the following general formula (B): ##STR2## as an image-forming component.

Abstract: An improved heat transfer means provides for a dual corrugated fin material which improves heat transfer by increasing the surface area of the fin without a corresponding increase in volume. The improved heat transfer means comprises a fin generated from a flat sheet of metal. The fin includes a first corrugated pattern having a first height, and a second corrugated pattern having a second height, wherein the first pattern is integral in the second pattern and the first height is less than the second height.