Abstract: An automatic system to precisely maintain bactericidal action in a reservoir of water equipped with a recirculation system, such as a swimming pool, decorative fountain, spa, cooling water reservoir or the like. The automatic system includes: a service loop which bypasses a portion of the recirculating water past sensors which measure the pH and oxygen reduction potential (ORP) of the water and in which acid and halogen are injected by a chemical feed unit; an electronics unit for determining the injection quantity of the acid and/or halogen needed to restore pH and ORP to stored set-points, and for controlling the chemical feed unit in response to the injection time determination; and an optional telecommunication unit for reporting process control status to a remote location and allowing modification of the process parameters, selection of operating modes, and performance of diagnostic tests from the remote location.

Abstract: A method and system for regulating the temperature of a hot melt ink wherein light reflected from a phase change material adjacent to the ink is detected, and a closed loop control signal proportional to the intensity of the reflected light is generated. The control signal is applied to a heater element for the ink and provides good temperature control thereof. In addition, the phase change material is used to generate an ink level indication signal which is also processed in a closed loop servo system in order to provide control over levels of the hot melt ink during operation of an ink jet printhead. In the embodiment of the present invention for controlling both ink temperature and ink levels within a pen body housing, there is provided a means and method for simultaneously sensing the liquid level and temperature at the solid/liquid interface within the pen body housing.

Abstract: An integrated circuit for use in the printhead of an ink jet printer includes an array circuit for heating an ink reservoir to produce a pattern of ink jets, the array circuit including a plurality of resistor cells arranged into rows and columns. A corresponding number of row and column lines are coupled to the integrated circuit array for selecting and energizing the resistor cells according to the desired printing pattern. An identification circuit integrated into the same substrate as the array circuit includes one or more programmable paths, the programmable paths corresponding and coupled to each row line. The programmable paths each include the serial combination of a programmable fuse and an active device. The opposite end of the programmable paths are coupled together at a common node, which in turn is coupled to an output circuit for providing a single output signal in response to a polling of the row lines.

Abstract: For an ink-jet printer, an indication of the quantity of ink remaining gives the user useful information about when to replace a disposable printhead or ink cartridge. The invention disclosed herein provides a means for computing remaining ink and for sensing a true low-ink and out-of-ink condition. Ink is supplied to a printhead (24) by an elastic bladder (16) which is periodically refilled from an ink bag (14). The bladder is designed to collapse in a repeatable manner as ink is consumed. A sensor probe (100), which moves along the bladder's collapse axis, dimples the bladder prior to printing to initialize the collapse mode. The probe position along the axis is measured when its sensitive tip (102) touches the bladder. The difference between bladder positions before and after refill is used in an algorithm to compute the bladder's volumetric change. This is the ink consumed on each print cycle, and gives the quantity of ink remaining when subtracted from an initial value.

Abstract: An ink jet print cartridge liquid toner container (14) is refillable at a service station (60) in a printer (50). Liquid toner is forced into the liquid toner container (14) from a liquid toner reservoir (70) through a refill tube (26) extending into the interior of the foam-filled container (14). Simultaneously, a volume of air and toner is withdrawn from the upper portion of the foam (20) through an evacuation tube (30) at a rate equal to or greater than the refill rate. Typically, a portion of the volume of foam (20) is filled with air so that the foam (20) fills with toner as air is removed.

Abstract: A liquid delivery system for delivering inks of three or more different colors or densities or dye-forming reactive components comprising multiple liquid reservoirs, liquid bladders, and valves that permit (a) total interruption of liquid flow, (b) liquid flow from reservoirs to bladders and (c) flow of liquid from bladders to printhead, the latter adapted to handle toners of three different colors, optical densities or chemical composition. The valves and ink flow channels are arranged in an upper manifold, gasket and lower manifold, all of which serve as support for the bladders and dimpler system.

Abstract: This patent application discloses a method and apparatus useful for eight-level halftone thermal ink jet printing by printing with droplets of ink with volumes weighted in a binary sequence. Three (3) binary-weighted drop generators which are fired in sequence are useful in an eight-level, four color printing process and additionally may be employed with a clear ink vehicle drop generator in order to reduce optical density of single small dots in a given pixel area to thereby reduce grainyness.This method and apparatus are also adapted for four color printing with a chosen number of rows of binary-weighted drop generators, including untoned vehicle if desired, in order to achieve color printing of pixels having desired color and optical density.

Abstract: A nozzle plate for impulsive jet devices is proposed where the quality of ejected droplets is improved by means of additional non-emitting orifices. These orifices may act as fluid accumulators and tuned or untuned absorbers of pressure disturbances to optimize drop quality and reduce fluidic crosstalk between adjacent drop generators. The presence of these orifices permits additional degrees-of-freedom in the design of high-quality impulsive jet devices. Sufficient crosstalk reduction results that crosstalk reduction barriers can be eliminated.

Abstract: An ink jet drop generator is presented which has a nozzle plate containing at least one nozzle for controlled ejection of droplets of ink. The ejection of ink can be produced by a number of means including by production of a gas bubble in the ink in the vicinity of the nozzle. The nozzle plate also contains at least one drain hole to remove drops of ink from the outer surface of the nozzle plate. These drain holes are preferably connected to an accumulator having a pressure below ambient pressure to help draw drops of ink from the outer surface. The nozzle plate also contains isolator holes which are connected to a refill plenum to help dissipate disturbance energy in the ink to reduce fluidic crosstalk between emitters in multi-emitter heads.