Abstract: A method of and apparatus for compensating printing heads which operate in thermal drop on demand printing modes for the effects of thermal lag includes a counter which provides a number representing the amount of elapsed time during a heater energizing pulse as a proportion of the entire pulse duration. The output of the counter is connected to a device which determines the power supply voltage required at the said elapsed time. This result is used to control a programmable power supply which is connected to the heater power supply of the print head. The device is preferably a lookup table stored in digital memory, containing a pulse waveform calculated using iterated transient finite element analysis of the thermal state of the nozzle during simulated operation.

Abstract: In the recording method and apparatus, ink is ejected by thermal energy produced by a heat generating element of a recording head in response to application of driving signals thereto, the driving signals being of plural waveforms including a fixed waveform. The method includes the steps of detecting a temperature of the recording head and applying the driving signals to the heat generating element of the recording head. The waveforms of the driving signals are changed in accordance with the temperature of the recording head when the temperature of the recording head is below a predetermined level, and the waveforms of the driving signals comprise the fixed waveform when the temperature of the recording head exceeds the predetermined level.

Abstract: A method of fabricating bubblejet print devices uses semiconductor fabrication techniques, and this method involves forming a heater means and an electrical connection to the heater means on a substrate, and forming a passageway through the substrate. A given end of the passageway is disposed adjacent to the heater means, and this given end is formed as an outlet for ejecting ink.

Abstract: It is an object of the present invention to provide an image recording method and apparatus for performing stable image recording with a minimum power consumption. An AND gate performs an AND operation of a clock signal and a printing signal of binary logic in units of pixels, and a transistor is driven. At the driving timing, an induced electromotive force is generated in a choke coil having one end connected to a power supply line. A capacitor is charged with a forward current through a diode. On the other hand, the signal is shift-input to a shift register and latched by a latch circuit in synchronism with a signal. An output from the latch circuit is supplied to a gate circuit in synchronism with a signal to drive a transistor. A current from the capacitor is input to the transistor to heat a heater.

Abstract: A method of clearing nozzles of thermally activated drop on demand printing head which have been blocked by dried ink by applying a consecutive sequence of heater energizing pulses. The method is particularly applicable to coincident forces drop on demand printing systems. A series of consecutive pulses is applied to the heater. These pulses accumulate heat at the nozzle tip, and the ink in contact with the tip, above the boiling point of the ink. The formation of vapor bubbles at the tip can dislodge a crust of dried ink, which is then expelled with the ink drop. A single power pulse of longer than normal duration, or greater than normal energy, can be used. However, this may require substantial additional electronic circuitry to generate. The need for this circuitry is eliminated by applying an integral number (greater than one) of consecutive power pulses of the energy, duration, and time varying power profile that is used to expel drops on demand under normal operating conditions.

Abstract: A wide array ink jet printhead for use in an ink jet printing device and being capable of propelling ink to create a line on a recording medium in the device. The printhead includes a plurality of adjacent and generally linear printheads each having a first and second end ink jet. A plurality of electrodes are in communication with the ink jets. A microprocessor controls the electrodes to selectively provide a current signal representing digitalized data to the electrodes. When the digitalized signal is intended to create a line on the recording medium more than one printhead wide, the ink jets on adjacent printheads forming the line are initialized from a first end ink jet to a second end ink jet on a first printhead and in a reverse order from a second end ink jet to a first end ink jet on the adjacent printhead, the sequences commencing substantially simultaneously on each printhead.

Abstract: There is provided a driving method for an ink jet head comprising one or more discharge ports for discharging the ink, a substrate incorporating one or more heat generating elements for generating the heat energy, each of which is provided correspondent to each discharge port, and a support plate or casing on which the substrate is mounted. The method is characterized in that when recording an image with the ink jet head in which the heat energy for discharging the ink in accordance with an image signal is generated in the heat generating elements, and the thermal resistance value passing through said support plate or casing is lower than that not passing through the support plate or casing among the thermal resistance between the substrate and externally of the apparatus (E.sub.max -E)/(V.sub.max -V) is controlled to be always substantially constant whenever E.noteq.E.sub.max, providing that the thermal energy generated in the substrate is E.sub.

Abstract: By increasing/deceasing electric energy per unit time supplied to heat energy generation means arranged in a liquid chamber having a nozzle, the amount of the ink emitted from the nozzle can be changed to correct a difference in dot diameter which occurs nozzle by nozzle and a change in dot diameter with time and to permit gradational printing.

Abstract: In an ink print head of sandwich type construction which works according to the bubble-jet principle, the heating elements, electric lines and contacts, as well as the shoot out openings are advantageously produced in the same chip by planar processing steps (back-shooter principle). The heating elements and the shoot out openings are arranged so as to be laterally offset relative to one another in such a way that the spreading direction of the steam bubble is directed opposite to the ink shooting direction. Such an arrangement results in a simple and accordingly inexpensive production of such ink print heads since all precision processing steps are advantageously effected in a planar process and joined on one element.

Abstract: An inkjet printhead addressing and firing design which minimizes voltage drop differential occurring on a power bus which supplies power to fire individual ink jets due to current loads needed to fire the individual ink jets. The voltage drop differential can be reduced in part by firing a group of individual jets which are spaced out over the entire length of the array instead of firing a group of adjacent jets. Spacing of the firing jets will insure that less than an entire amount of current needed to fire a group of jets will be needed in the center of the bus. Reducing the amount of current needed to travel the length of the bus reduces the voltage drop differential on the bus caused by current conduction along the bus.

Abstract: A method of controlling the operation of an ink jet printhead having a burn voltage applied to a transducer nucleating an ink bubble to cause an ink droplet to be ejected from an ink ejecting orifice. The method includes determining a threshold power dissipated by the transducer sufficient to cause the bubble to nucleate, the threshold power being determined by a firing pulse having a pulse length and a threshold voltage, selecting the pulse length of the firing pulse to be approximately equal to a pulse length necessary to achieve the highest effective power dissipation in the transducer, and selecting the burn voltage as a function of the threshold voltage. Changes to the threshold power dissipated by the transducer necessary to eject from the ink ejecting orifice are determined and the pulse length of the firing pulse is adjusted accordingly.

Abstract: A thermal ink jet printer includes a plurality of ink channels filled with ink, and a plurality of nozzles corresponding to respective ones of the plurality of ink channels individually. Each nozzle brings the corresponding ink channel into fluid communication with an outside atmosphere. A plurality of protection-layerless heaters are provided on respective ones of the plurality of ink channels individually to face a corresponding nozzle. An LSI device with drive circuits is connected to each heater for applying a print signal to a selective one of the heaters. To drive the printer, every other heater is sequentially driven at a predetermined interval of less than 1 microsecond so that ink droplets are sequentially ejected, when the print signals are produced, from odd-numbered nozzles and thereafter from even-numbered nozzles.

Abstract: An ink ejection printer includes an ink channel filled with ink, a nozzle which brings the ink channel into fluid connection with an outside atmosphere, and a thermal resistor formed in the ink channel near the nozzle. The thermal resistor received a pulse of voltage, whereupon the thermal resistor rapidly heats so that a portion of the ink in the ink channel is rapidly vaporized by subcool boiling, which is caused by swing nucleation, to produce a bubble, expansion of the bubble ejecting an ink droplet from the nozzle. With the thermal resistor, boiling starts within 2 .mu.S after application of the pulse of voltage begins. The pulse of voltage is applied to the thermal resistor for a duration of 3 .mu.S or less. The bubble generated by application of the pulse of voltage to the thermal resistor disappears without the thermal resistor generating secondary bubbles. The bubble generated by application of the pulse of voltage of the thermal resistor disappears within 11 .mu.S after application of the pulse.

Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.

Abstract: A manufacturing method for an ink jet recording head comprising ink ejection outlets, ink passages in fluid communication with the ink ejection outlets, an ink chamber for supplying ink to the ink passages, energy generating elements for ejecting ink, a grooved top plate having ink passage walls, an ink chamber frame for defining the ink passages and the ink chamber and the ink ejection outlets, a substrate for supporting the energy generating elements, wherein the ink passages and ink chamber are formed by coupling the grooved top plate and the substrate, the improvement residing in that the grooved top plate is molded, and after the molding, a laser machining is effected to a neighborhood of a connecting portion between the ink chamber frame and a passage wall.

Abstract: A method for operating a thermal ink jet printer including a printhead having a sample resistor and ink firing heater resistors responsive to pulses provided to the printhead. The resistance of a sample resistor is read and the pad to pad resistance of the printhead is determined. The operating energy of the printhead is determined from a look-up table and the target power is determined from the target pulse width. The power supply voltage is determined from the target power and the power supply voltage is set. The operating power is determined and the operating pulse width is set based on the operating power and target energy.

Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.

Abstract: An integrated printhead which includes an M row by N column array of groups of ink jet elements wherein each group has a unique row and column address; a first addressing control coupled to the array of groups for selecting one of the M rows of the M row by N column array of groups of ink jet elements; and a second addressing control coupled to the array of groups for selecting one of the N columns of the M row by N column array of groups of ink jet elements. One individual group of ink jet elements is addressed by the first addressing and the second addressing controls. In a specific embodiment a third dimension of addressing is provided by a plurality of address line selects that are coupled to the ink jet elements in each group. In an alternate specific embodiment the resistance between the first addressing means and the second addressing means for each group of ink jet elements can be adjusted to balance the energy dissipated between the groups of ink jet elements.

Abstract: An ink jet apparatus includes an ink jet head having a plurality of ejecting ports arranged in a predetermined pattern and a plurality of heat generating elements arranged corresponding to the ejecting ports, and a driving controlling means for applying a driving signal to heat generating elements 1e in response to a driving information wherein a printing mode of printing a printing medium by ejecting ink from the ejecting ports and a preliminary ejecting mode of performing no ejection toward the printing medium are settled for the apparatus. The driving controlling means includes a defoaming position changing means for changing the position of a defoaming point P.sub.B arising on each heat generating element 1e when ink is ejected in conformity with the preliminary ejecting mode.

Abstract: An ink jet recording method includes the steps of inputting a set of driving pulses to a heater element so that the heater element is repeatedly activated by the driving pulses, repeatedly generating a bubble in ink in an ink path in accordance with repeated activation of the heater element, and separately jetting ink droplets from an ink jetting orifice due to the bubble repeatedly generated in the ink, a number of the ink droplets being equal to a number of the driving pulses input as a set to the heater element, the ink droplets jetted from the ink jetting orifice forming a single dot on a recording medium, wherein a time interval at which the driving pulses are input to the heater element is equal to or greater than 4T, T being a time period from a time at which the inputting of the pulses to the heater element starts to a time at which the bubble reaches a maximum size, and each ink droplet is a slender pillar so that a length of each ink droplet is at least three times as great as a diameter thereof.

Abstract: A thermal ink jet printer including a printhead having a plurality of ink drop firing resistors responsive to ink drop firing pulse groups wherein a pulse group includes one or more pulses sufficiently closely spaced to produce respective droplets which merge in flight to form an ink drop whose volume depends on the number of pulses in the pulse group. The pulses in a pulse group are controlled such that the energy of the second and successive pulses is less than the energy of the first pulse. The intervals between leading edges of the pulses in a pulse group can be constant or reduced such that the intervals between adjacent pulses beginning with the second pulse is less than the interval between the leading edges of the first and second pulses.

Abstract: A bipolar ink jet driver circuit includes a plurality of individual driver cells having a common collector and a resistive heater element. A common collector obviates the need for any isolation between adjacent driver cells. The driver cells each include two bipolar transistors configured as a Darlington pair, which drive an associated resistive heater element. The cells are grouped together to form individual driver circuits each having a control line for enabling each driver circuit. The cells within each driver circuit are individually addressable via address lines which are coupled to each of the driver elements. The resistive heater elements are actuated by enabling a driver circuit and addressing a driver cell within the enabled driver circuit.

Abstract: An ink jet recording apparatus comprises a plurality of ink discharge portions having discharge ports for discharging ink, ink channels communicating to the discharge ports, and electricity-heat converters for applying the heat energy to the ink within the ink channels, which electricity-heat converters are divided into plural groups supplied with separate signals for generating heat energy, and a conveying mechanism for conveying a recording medium to be recorded with the ink discharged from the discharge ports. The shapes of the ink discharge ports or other geometrical properties of the apparatus are changed for different groups of electricity heat converters to compensate for variations in the velocity of the ink discharged from the different groups.

Abstract: A method for operating a thermal ink jet printer including a printhead having ink firing heater resistors responsive to pulses provided to the printhead. Warming voltage pulses are applied to the printhead to warm the printhead to a temperature that is at least as high as a temperature that would be produced pursuant to ink firing pulses of a predetermined voltage, a predetermined pulse width, and a predetermined pulse frequency. A continuous series of ink firing pulses are then applied to the printhead, starting with a pulse energy substantially equal to the predetermined reference pulse energy and a pulse frequency equal to the predetermined pulse frequency, and then incrementally decreasing the pulse energy of the ink firing pulses. The temperature of the printhead is repeatedly sampled while the ink firing pulses are applied to the ink firing resistors to produce a set of temperature samples respectively associated with the decreasing pulse energies.

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.

Abstract: A control system for a printer having at least one heating element for producing spots applies one of a plurality of voltage levels to at least one heating element disposed on a printhead. A voltage supply supplies a voltage to a first one of a plurality of switches connected in series with a last one of the switches being connected to the at least one heating element. At least one of the switches defines a first path and a second path having different voltage drops. A controller coupled to the plurality of switches selectively actuates the switches to apply one of a plurality of predetermined voltages to the at least one heating element.

Abstract: An information recording apparatus comprises a recording unit for recording on a recording medium and control means for controlling the recording unit to twice eject droplets to the same position on the recording medium so that the tone of the recording is emphasized. In another aspect of the disclosure, an image forming apparatus includes a storage unit for storing recording material, an image forming unit in which an image is formed without contacting the recording material and a discharge unit for discharging the recording material on which the image has been formed. A transporting mechanism transports the recording material from the storage unit, through the image forming unit to the discharge unit along a U-shaped transporting path.

Abstract: A flexible lead frame type tab circuit including a flexible dielectric substrate, a plurality of conductive elements disposed on the dielectric substrate, and fusible links connected between selected conductive elements to enable selective electrical isolation between conductive elements and to enable encoding of machine readable information on the flexible tab circuit.

Abstract: Disclosed is a recording apparatus using a recording head for recording in line units and having a recording mode for recording on a recording medium by repeatedly recording recording data for one line a plurality of times. A counting means counts a time interval between the termination of recording for one line and the start of recording for a next one line. A controlling means controls energy to be applied to the recording head at recording for the next one line in accordance with a time interval counted by the counting means.

Abstract: An ink jet recording apparatus is provided with an ink jet recording head which includes at least one nozzle for ejecting ink, a heating layer, and a ground electrode and a plurality of control electrodes electrically connected to the heating layer, and a thermal energy action part, formed in the heating layer in correspondence with the nozzle, for heating the ink and causing a state transition so as to eject the ink from the nozzle when a voltage is applied across at least one pair of the ground electrode and the control electrode. The ground electrode electrically connects to the heating layer within a region of the thermal energy action part, and the control electrodes electrically connects to the heating layer outside the region of the thermal energy action part.

Abstract: A method for operating a thermal ink jet printer including a printhead having ink firing heater resistors responsive to pulses provided to the printhead. A sequence of pulse bursts of respective increasing or decreasing pulse energies that span a predetermined pulse energy range is applied to the printhead, each pulse burst comprised of a plurality of pulses having a pulse energy that is associated with such pulse burst and is constant for all pulses in such burst, and each burst having a sufficient number of pulses to allow the printhead to achieve a steady state operating temperature at the pulse energy of the pulse burst. A steady state operating temperature sample is determined for each of the sequence of pulses bursts of different pulse energies to produce a set of temperature samples respectively associated with the increasing pulse energies, and a turn on pulse energy is determined from the temperature samples.

Abstract: A thermal ink jet printhead includes a switched power supply for the intermediate voltage predriver sections. The power supply is switched by a MOSFET connected between an intermediate point of a voltage divider and ground. By switching the power supply, the predriver sections are turned off, unnecessary power consumption and overheating the printhead are avoided.