Abstract: A passive fluid management component for a direct oxidation fuel cell is provided. It enables the introduction of highly concentrated methanol solutions, including neat methanol, directly into the anode, eliminating the need of mechanical modes of dosing and/or mixing a methanol/water solution to control the local concentration at the anode. The fluid management of the present invention can be based on pores formed in the component of a specific size and spacing to allow anode reactants to flow through the component towards the anode face of the membrane electrolyte of the fuel cell at a controlled rate. The pore size can be adjusted to allow the highest concentrations possible of methanol, including neat methanol, to be introduced in direct contact with the outer face of the component, said component being capable of lowering, under current, the local concentration of methanol at the anode face of the membrane electrolyte to the level required to minimize methanol loss.

Abstract: An arrangement for printing a raster image organized into a plurality of scan lines on a recording medium, the arrangement including a memory and a printbar. The memory contains scan line data representative of said scan lines. The printbar includes a plurality of nozzles and a printbar circuit. The printbar circuit includes an output buffer and a serial data buffer. The serial data buffer is operably connected to receive serially the scan line data such that the serial data buffer includes scan line data corresponding to a first scan line. The output buffer is operably connected to receive the scan line data from the serial data buffer. The printbar circuit is further operable to cause the plurality of nozzles to print on the recording medium in accordance with the scan line data stored in the output buffer.

Abstract: An arrangement for printing a raster image organized into a plurality of scan lines on a recording medium, the arrangement including a memory and a printbar. The memory contains scan line data representative of said scan lines. The printbar includes a plurality of nozzles and a printbar circuit. The printbar circuit includes an output buffer and a serial data buffer. The serial data buffer is operably connected to receive serially the scan line data such that the serial data buffer includes scan line data corresponding to a first scan line. The output buffer is operably connected to receive the scan line data from the serial data buffer. The printbar circuit is further operable to cause the plurality of nozzles to print on the recording medium in accordance with the scan line data stored in the output buffer.

Abstract: An improved fuel delivery system and fuel cell system is provided which includes a component, which delivers fuel from the fuel cartridge by connecting with a corresponding component in the anode chamber of the fuel cell. Liquid fuel is transported into the anode area via an action in which fuel is drawn through the material which may be substantially comprised of a foam-based substance. Gases, including carbon dioxide, that are produced in the anodic reaction can be removed because the foam is gas permeable. Electrons produced in the reaction are collected by a wire mesh that lies between the foam and the membrane electron assembly. The flow of fuel between the foam and the fuel cartridge and the foam and the anode can be interrupted by breaking the connection between the cartridge and the cell, or the cartridge can be pulled away from the fuel cell to break the connection between the foam components. The invention may be employed with a fuel cell stack, or with an enclosed, refillable fuel cell system.

Abstract: A simplified direct oxidation fuel cell system is disclosed. The fuel cell is constructed in such a manner that fuel is added to the cell anode as it is consumed and water is evaporated off at cell cathode so that there is no need for recirculation of unreacted fuel at the cell anode or water at the cell cathode. In addition, carbon dioxide generated from the anodic reaction is passively vented out of the system by using a CO2 gas permeable membrane material integrated as part of the anode chamber construction. It is thus possible that, the CO2 separation from the anode fluid occurs without the recirculation of the anode fluid outside the anode chamber. In one embodiment, the simplified direct oxidation fuel cell includes a gas permeable, liquid impermeable membrane placed in close proximity to the anode to perform the carbon dioxide separation.

Abstract: A method and Apparatus for protection of semiconductor micromechanical devices that use circuits with dynamic logic addressing is disclosed. In one exemplary embodiment of the invention, a fail-safe circuit is provided for an ink jet print head integrated circuit which prevents a catastrophic consequence of the dynamic logic addressed integrated circuit losing its charge.

Abstract: A liquid feed fuel cell system having a unique fuel container and delivery assembly is provided. The container and delivery assembly allows liquid fuel which, in a preferred embodiment, is in the form of either pure methanol or an aqueous methanol/water mixture, to be placed under pressure so that it is delivered to the cell in a continuous manner. The fuel substance is stored in a flexible bladder that is housed in an outer container. The inner flexible bladder containing the fuel is fitted with a pressure-applying element that exerts a continuous pressure upon the fuel-containing flexible bladder to maintain pressure on the bladder in such a manner that the fuel is expressed through a conduit in the container, to the direct oxidation fuel cell in a continuous manner. The fuel container and delivery system of the present invention delivers fuel simply and inexpensively to the liquid feed fuel cell while it is being used in any orientation.

Abstract: Print quality is maintained by determining print conditions based on varying threshold values over the printhead lifetime before the print run. In particular, print conditions are determined through periodic quality adjustment cycles based on detected long-term and short-term temporal drift of print thresholds. A detector is provided to detect the presence or absence of ink being ejected from an inkjet printer. A sequence of eject and detect cycles over varying control conditions is performed to determine the minimum condition required to eject ink from the printer.

Abstract: A method and apparatus for controlling the volume of ink droplets ejected from printhead nozzles over a larger printhead operating temperature range. Each nucleating electrical pulse applied to the heating elements in the printhead to eject an ink droplet is preceded by a plurality of non-nucleating pre-pulses. Based upon the printhead temperature sensed, a controller selects the pre-pulse width and time width between pre-pulses from a look-up table.

Abstract: An ink jet printer including an ink jet printhead and a printhead temperature sensing device including a fusible link circuit with a preview feature and a method for programming or calibrating therefore. The ink jet printhead includes a fusible link circuit including a fusible link, with a threshold above which the fusible link will be forced to an open condition with the application of a threshold condition applied thereto and a circuit, coupled to the fusible link, including an input and an output, generating an output signal on the output in response to a signal being applied to the input, wherein the output signal provides an output state which simulates the open condition of the fusible link as a preview feature. The fusible link circuit includes the preview feature so that the output of the temperature sensing device which must be calibrated, programmed, or have its output set to a predetermined value, can be simulated or previewed to determine whether the correct output has been achieved.

Abstract: A fusible link circuit including a preview feature and a method for programming or calibrating therefore. The fusible link circuit includes a fusible link, including a threshold above which the fusible link will be forced to an open condition with the application of a threshold condition applied thereto and a circuit, coupled to the fusible link, including an input and an output, generating an output signal on the output in response to a signal being applied to the input, wherein the output signal provides an output state which simulates the open condition of the fusible link as a preview feature. The fusible link circuit includes the preview feature so that the output of any circuit, which must be calibrated, programmed, or have its output set to a predetermined value, can be simulated or previewed to determine whether the correct output is obtainable without destroying the fusible links.

Abstract: A liquid recording apparatus ejects droplets of liquid onto a recording medium. The apparatus has multiple liquid emitters whose emissions are activated by multiple power pulses. The power pulses are controlled to maximize the number of emitters which can be simultaneously energized while keeping the instantaneous power usage within prescribed boundaries. The multiple emitters are organized into banks of emitters whose numbers are small enough that all emitters within a bank can receive a correct level of power simultaneously without exceeding capacity of a shared power source. A circuit interleaves the power pulses to the emitters so that no bank of emitters are receiving power at the same instant of time.

Abstract: An improved temperature compensation method is disclosed in which a temperature sensing thermistor is formed on a substrate whose temperature is to be series of fractional thermistors which are selectively shorted out during a manufacturing process to provide a compensation for manufacturing variabilities of the temperature coefficient of resistance of the thermistor.

Abstract: An ink jet printing system includes an ink jet printhead which has an n-bit code representing a unique characteristic of the printhead formed on a substrate forming a part of the printhead. An n-bit data code is sent from a remote source to the printhead. If the data code matches the code on the printhead, printing operation is initiated. If the code is not matched, the print operation is inhibited.

Abstract: The invention describes a temperature sensing system which provides a digital signal representative of the temperature of an ink jet printhead during a predetermined time period. In one embodiment, a temperature controlled oscillator is formed on the printhead, the oscillator including a resistor whose resistance varies proportional to printhead temperature variations. An analog signal from the resistor representative of printhead temperature is converted by the oscillator into a digital output signal whose frequency varies with variations in the resistor and, therefore, with the printhead temperature. The oscillator outputs are counted in an electrical counter over a sampling period. The accumulated count is converted into a digital code representing the printhead temperature.

Abstract: A protection circuit prevents snapback events in MOS transistors associated with semiconductor or micromechanical structures, such as ink-jet ejectors. A bulk electrode associated with the MOS transistor is monitored for unusual high voltages which are consistent with an impending snapback event. The voltage on the bulk electrode is then used to turn on the control transistor which connects the gate of the MOS transistor to ground and thereby protects the device.

Abstract: An ink jet printer has a temperature sensor as a permanent part thereof to measure the temperature of printheads which are an integral part of a replaceable printhead cartridge assembly. The temperature sensor is a part of the maintenance station and senses the temperature of the printheads each time the printhead enters the maintenance station. In the preferred embodiment, the temperature sensor is spring-loaded and is located at a printhead spitting location between fixed wiper blades and the capping location in the maintenance station, so that temperature is sensed each time the printhead enters and leaves the maintenance station to eject nozzle cleaning droplets onto a collection surface at the spitting location to clean the printhead nozzle face by the wiper blades, or to cap the printhead nozzles. To facilitate good thermal contact, a recess is provided in the heat sink upon which the printhead resides for entry by the spring-loaded temperature sensor.

Abstract: An ink-jet printhead accepts a series of digital addresses as image data. Each digital address causes an individual ejector in the printhead having the particular address to be activated. The frequency of operation of the printhead can be directly related to the frequency at which addresses are submitted to the printhead. A scheduler polls image data for spot placements which require simultaneous activation of a plurality of ejectors in a set of interdependent ejectors, and then reschedules the activation of ejectors to avoid conflicts.

Abstract: An ink jet printer has a temperature sensor as a permanent part thereof. The temperature sensor is mounted on the translatable carriage of the printer. A replaceable printhead cartridge having a printhead bonded to a heat sink is installed on the translatable carriage. Once the printhead cartridge is installed on the translatable carriage, the temperature sensor is placed into intimate contact with printhead'heat sink, so that the temperature sensor moves with the printhead and provides continual temperature measurement.

Abstract: A method and apparatus for maintaining a print quality of an ink jet apparatus comprises selecting one of a plurality of different pulse signals to apply to at least one heating element. The heating element is energized with the selected pulse signal. An actual voltage drop is then measured across the heating element. The actual voltage drop is subsequently compared with a desired voltage drop. Then, a new pulse signal is selected to energize the heating element based on the results of the comparison. The repetitive process continues until the actual voltage drop is substantially equal to the desired voltage drop. In another embodiment, a bubble sensor is used to determine whether a bubble has been formed over the heating element.