Abstract: An image forming apparatus includes: a liquid droplet discharge head; a pressure generator; and a driving waveform generator configured to generate a driving waveform including a plurality of pulse units for driving the pressure generator for discharging a liquid droplet. The pulse unit includes one or more first pulses, and one or more second pulses arranged after the first pulses for discharging a liquid droplet. The second pulse has a pulse width that is set in advance to generate a resonance with the liquid droplet discharge head. The first pulse has a pulse width different from the pulse width of the second pulse.

Abstract: A method of ejecting a drop of fluid includes providing a fluid ejector. The fluid ejector includes a substrate, a MEMS transducing member, a compliant membrane, walls, and a nozzle. The substrate includes a cavity and a fluidic feed. A first portion of the MEMS transducing member is anchored to the substrate. A second portion of the MEMS transducing member extends over at least a portion of the cavity and is free to move relative to the cavity. The compliant membrane is positioned in contact with the MEMS transducing member. A first portion of the compliant membrane covers the MEMS transducing member, A second portion of the compliant membrane being anchored to the substrate. Walls define a chamber that is fluidically connected to the fluidic feed. At least the second portion of the MEMS transducing member is enclosed within the chamber. A quantity of fluid is supplied to the chamber through the fluidic feed.

Abstract: A drive signal generating unit that generates a drive signal applying, in one pixel period, at least one drive waveform for causing ink droplets to be discharged can generate two types of drive waveforms, a large droplet waveform and a small droplet waveform. The large droplet waveform includes an expansion pulse expanding the volumes of pressure chambers and a contraction pulse making the volumes of the pressure chambers contract. The expansion pulse width of the large droplet waveform is 2.8 AL or longer but 3.4 AL or shorter. The small droplet waveform includes an expansion pulse, a pause period, and a contraction pulse, and the expansion pulse width of the small droplet waveform is 0.8 AL or longer but 1.2 AL or shorter, where AL represents a half of an acoustic resonance period of a pressure wave in the pressure chamber.

Abstract: A liquid ejecting apparatus includes a reference drive signal generation section that generates a reference drive signal, a signal modulation section that modulates the reference drive signal to generate a modulation reference drive signal, a signal amplification section that amplifies the modulation reference drive signal using switching elements to generate a modulation drive signal, a signal conversion section that converts the modulation drive signal to a drive signal, a piezoelectric element that deforms in response to the drive signal, a pressure chamber that expands or contracts due to the deformation of the piezoelectric element, and a nozzle opening portion that communicates with the pressure chamber. A period of alternating current components contained in the modulation drive signal are shorter than a duration of a maximum voltage or a minimum voltage, and is longer than a total time of turn-on delay times and turn-off delay times of the switching elements.

Abstract: A method for calibrating in situ a plurality of printheads in an imaging device has been developed. Firing signals operate a plurality of printheads to form ink test patterns on an image receiving member. Reflectance measurements of light reflected from the test patterns and optical density measurements for a portion of the patterns formed by only one printhead in the plurality of printheads are used to adjust the firing signals and enable the printheads to print within a predetermined range about an average reflectance value and a predetermined optical density.

Abstract: A time from a start end of a contraction portion of a first middle dot drive pulse of a first drive signal to a start end of the contraction portion of a second middle dot drive pulse of a second drive signal is set to Tc/2 or more and Tc or less in the same unit period. In addition, a time from a start end of a preliminary portion of a first small dot drive pulse to a start end of a preliminary portion of a second small dot drive pulse is set to Tc or more. Thus, while a piezoelectric vibrator corresponding to the other side of adjacent nozzles is driven by the second drive signal, a piezoelectric vibrator corresponding to one side of adjacent nozzles is driven by the first drive signal.

Abstract: A method of operating an inkjet printing system includes turning a heater voltage power source providing drop generation power to an inkjet printhead on or off under direction of a controller; providing a fire control pulse for setting a duration of passage of current from the heater voltage power source through one or more resistive heaters for generation of one or more drops of ink under direction of the controller; inputting the fire control pulse into a protective circuit; and overriding the fire control pulse in the setting of the duration of passage of current from the power source through the one or more resistive heaters if the pulsewidth of the fire control pulse is greater than or equal to a predetermined length of time.

Abstract: An inkjet printhead includes an array of resistive heaters; an array of nozzles associated with the array of resistive heaters; a heater voltage input for providing a heater voltage; a fire control pulse input for providing a fire control pulse having a first pulsewidth for controlling a length of time that current from the heater voltage input is allowed to pass through at least one of the resistive heaters; and a protective circuit configured to receive the fire control pulse from the fire control pulse input, and to override the fire control pulse if the first pulsewidth is greater than or equal to a predetermined length of time.

Abstract: A power supply section includes a switching regulator. A plurality of linear regulators is provided for respective ones of a plurality of driving sections. The linear regulators step down a source voltage to respective driving voltages of the driving sections and supply the respective driving sections with the driving voltages. A head-temperature sensor measures temperature of a liquid ejecting head. A controller determines the source voltage and the driving voltages based on the temperature, and controls the power supply section, the linear regulators, and the driving sections to stop at least one of outputting of the source voltage by the power supply section, supplying of the driving voltages by the linear regulators, and driving of the driving sections, when a voltage difference is larger than or equal to an acceptable value. The voltage difference is a difference between the source voltage and a minimum voltage of the driving voltages.

Abstract: A liquid ejecting apparatus includes a drive signal generation section which generates a drive signal and a liquid ejecting head. The drive signal is a periodic signal. One period of the drive signal has two durations of (i) a droplet ejection duration with a waveform part used to eject the droplet from the nozzle and (ii) a droplet non-ejection duration without the waveform part used to eject the droplet from the nozzle, and the droplet non-ejection duration is equal to or longer than the droplet ejection duration.

Abstract: A liquid discharge apparatus includes first and second discharge sections, first and second connection paths and a voltage generation section. Each of the first and second discharge sections has a nozzle configured and arranged to discharge a liquid, a pressure chamber in communication with the nozzle, and a piezoelectric element. The first connection path selection section is arranged so as to correspond to the first discharge section and configured to selectively supply a plurality of voltages to the first discharge section. The second connection path selection section is arranged so as to correspond to the second discharge section and configured to selectively supply a plurality of voltages to the second discharge section. The voltage generation section is configured to generate and supply the voltages shared by the first connection path selection section and the second connection path selection section.

Abstract: Each of M head units of a print head includes a driving signal generator and a plurality of piezoelectric elements. A common control signal is supplied from a control signal supply portion of a control unit to the respective driving signal generators of the M head units. The driving signal generator of each head unit generates a driving signal from the control signal according to characteristics (for example, relationship of a deformation amount with respect to an applied voltage) of each latter stage piezoelectric element and supplies the driving signal to each piezoelectric element.

Abstract: A head drive control unit generates and outputs a pulse formed of a first expansion waveform element to expand individual liquid chambers, a first contraction waveform element to contract the individual liquid chambers, a second expansion waveform element to expand the individual liquid chambers, and a second contraction waveform element to return the individual liquid chambers that have repeatedly expanded and contracted to an initial state. The first contraction waveform element serves as a waveform element that contracts the individual liquid chambers at a timing of resonance with a change in a pressure in the individual liquid chambers due to the first expansion waveform element. The second contraction waveform element serves as a waveform element that suppresses the change in the pressure in the individual liquid chambers.

Abstract: Described herein is a method, apparatus, and system for driving a droplet ejection device with multi-pulse waveforms. In one embodiment, a method for driving a droplet ejection device having an actuator includes applying a first subset of a multi-pulse waveform to the actuator to cause the droplet ejection device to eject a first droplet of a fluid in response to the first subset. The method includes applying a second subset of the multi-pulse waveform to the actuator to cause the droplet ejection device to eject a second droplet of the fluid in response to the second subset. The first subset includes a drive pulse that is positioned in time near a beginning of a clock cycle of the first subset. The first droplet has a smaller volume than the second droplet.

Abstract: A liquid ejecting apparatus includes a reference drive signal generation section that generates an analog reference drive signal, a signal modulation section that modulates the reference drive signal to generate a digital modulation reference drive signal, a signal amplification section that amplifies the modulation reference drive signal to generate a modulation drive signal, a signal conversion section that converts the modulation drive signal to an analog drive signal, and a liquid ejecting section that ejects a liquid in response to the drive signal. A sum of a resistance value of a reference drive signal transfer line and a resistance value of a drive signal transfer line is smaller than a sum of a resistance value of a modulation reference drive signal transfer line and a resistance value of a modulation drive signal transfer line.

Abstract: An image recording apparatus that includes a recording head controller that transfers image data and a driving waveform to a recording head in conjunction with position information of the recording head. The recording head controller includes a driving waveform storage unit that stores multiple driving waveform data, a number of driven nozzles calculator that calculates the number of nozzles driven simultaneously from the image data, and a driving waveform selector that selects one driving waveform data from the multiple driving waveform data based on the calculated number of driven nozzles and a predetermined threshold value of the number of driven nozzles.

Abstract: An ink jet head includes a plurality of nozzles and a piezoelectric member provided with driving channels for storing ink. Each of the driving channels communicates a respective one of the nozzles. Dummy channels are alternately arranged with the driving channels. First side walls between the driving and dummy channels include a first driving channel side surface and a first dummy side surface. Second side walls between the driving channels and the dummy channels include a second driving channel side surface and a second dummy channel side surface. When a voltage is applied to electrodes on the first dummy channel side surfaces, the corresponding first side wall is deformed. When a voltage is applied to electrodes on the second dummy channel side surfaces, the second side wall is deformed.

Abstract: According to one embodiment, an inkjet recording apparatus includes a head body, electrodes, a nozzle plate and a control section. The control section is electrically connected to the electrodes and applies an ejection pulse or a non-ejection pulse to the electrodes. The ejection pulse includes a first voltage change process for increasing the volume of a pressure chamber and a second voltage change process for reducing the volume of the pressure chamber, has width equal to or larger than 0.95 times and equal to or smaller than 1.05 times of a pressure propagation time in the pressure chamber, and ejects the ink from a nozzle. The non-ejection pulse has width equal to or larger than 0.2 times and equal to or smaller than 0.34 times of the width of the ejection pulse and stops the ink in the nozzle.

Abstract: An image forming apparatus includes a liquid ejection head including a pressure generation unit configured to generate a pressure for pressurizing a liquid in an individual liquid chamber communicating nozzles; and a head drive control unit configured to generate a drive waveform including pulses in time series, select one or more pulses from the drive waveform according to a droplet size, and provide the selected drive pulses to the pressure generation unit. The drive waveform includes a first pulse not including a waveform component that suppresses ejection bending, and allowing a droplet to be ejected, and a second pulse including the waveform component that suppresses ejection bending, and allowing a droplet to be ejected. An amount of the droplet ejected in the second pulse is larger than in the first pulse, and a speed of the droplet ejected in the second pulse is higher than that in the first pulse.

Abstract: A method for driving a piezoelectric element of a head, including: a step of increasing a voltage of a power source to a reference voltage level; and a step of charging one electrode of two electrodes interposing the piezoelectric element to the reference voltage level by repeating source-connections and source-disconnections between the power source and the one electrode while keeping the voltage of the power source at the reference voltage level, such that a ratio of a connection time of each of at least one of second and subsequent connections of the source-connections to a disconnection time of a corresponding source-disconnection continued from each of the at least one of the second and subsequent connections is greater than a ratio of a connection time of a first connection of the source-connections to a disconnection time of a source-disconnection continued from the first connection.

Abstract: A method for operating a jetting module includes applying to a drop forming mechanism a sequence of drop formation waveforms in which a small-drop waveform applied after another identical small-drop waveform causes a small drop of volume Vs to be formed; applying a large-drop waveform after another identical large-drop waveform causes a large drop of volume VL to be formed, and applying a large-drop waveform adjacent to a small-drop waveform can be done in a way that produces a large drop having a volume VL2, where VL2 is different than VL and a small drop of volume VS2, where VS2 is different than Vs.

Abstract: A basic driving waveform which includes a plurality of jet pulses and a non-jet pulse just before the last jet pulse in one recording period is generated. A part of the pulses is removed from the basic driving waveform by maintaining at least the last jet pulse, and a driving signal that is applied to a discharge energy generation element is generated. In the case of using only the last jet pulse among the plurality of jet pulses is used for the jet, a first driving signal that includes the non-jet pulse just before the last jet pulse is generated. In the case of joining the last jet pulse and at least another jet pulse among the plurality of jet pulses to use the pulses for the jet, a second driving signal that is configured to remove the non-jet pulse is generated.

Abstract: An image forming apparatus includes: a liquid ejecting head including a nozzle that ejects a droplet and a pressure producing unit that produces pressure to pressurize a pressure chamber communicating with the nozzle; and a head drive controlling unit that provides a driving signal to the pressure producing unit. The head drive controlling unit outputs the driving signal including at least a first driving pulse and a second driving pulse to eject droplets and a residual vibration suppressing pulse to suppress residual vibration in the pressure chamber without ejecting a droplet. The residual vibration suppressing pulse is output at such a timing that the residual vibration suppressing pulse has an opposite phase to a composite vibration Vab that is formed by superposition of a meniscus vibration Va generated by droplet ejection with the first driving pulse and a meniscus vibration Vb generated by droplet ejection with the second driving pulse.

Abstract: An ink-jet printing method includes the steps of dividing multiple ink droplet discharging pulses into two or more groups in an ink droplet discharging order, providing the multiple ink droplet discharging pulses to a pressure generator per scan line time, and discharging ink droplets from an ink droplet discharge head in accordance with the multiple ink droplet discharging pulses. The method further includes the steps of combining ink droplets of a former group as a first combined ink droplet, combining ink droplets of a latter group as a second combination droplet, combining the second combined ink droplet of the latter group with that of former group before the ink droplets reach a target, and maintaining a prescribed amount of ink droplets landing on the target by decreasing the number of ink droplet discharging pulses.

Abstract: An image forming apparatus includes a recording head and a driving waveform generator. The recording head has a nozzle, a liquid chamber, and a pressure generator. The driving waveform generator is connected to the pressure generator to generate and output a driving waveform including a plurality of driving pulses per driving cycle to eject a droplet from the nozzle. A last one of the driving pulses includes a first expansion waveform element, a first retaining waveform element, a first contraction waveform element, a second retaining waveform element, a second contraction waveform element, a third retaining waveform element, and a second expansion waveform element. The first contraction waveform element has a potential difference greater than a potential difference of the first expansion waveform element. The second contraction waveform element has a time period longer than a time period of the first contraction waveform element.

Abstract: A fire pulse circuit for use in an inkjet printer includes an input control signal transmitted from a controller to a logic AND gate and to fire truncation logic; fire truncation logic adapted to truncate a pulse width of the input control signal to a maximum allowable pulse width if the duration of the pulse exceeds a maximum allowable time; a logic AND gate that receives inputs from both the input control signal and the fire truncation logic to produce an output fire pulse signal that operates to optimally fire an inkjet heater driver logic to heat the heater to nucleate ink from the print head. The circuit is formed from either a combination of digital and analog components or from exclusively digital components. A method of using the circuit to generate an output fire pulse to an inkjet heater driver logic is also disclosed.

Abstract: Some of the embodiments of the present disclosure provide a method for generating each of (i) a first signal and (ii) a second signal based at least in part on a position of a carriage, where the carriage is a component of a printing device, estimating (i) a major cycle duration associated with the first signal and (ii) a first minor cycle duration associated with the second signal, estimating a position of the carriage based at least in part on the estimated major cycle duration and the estimated first minor cycle duration, and generating a plurality of print synchronization pulses based at least in part on the estimated position of the carriage.

Abstract: A printer has a plurality of dischargers for discharging ink, a detector for detecting an electric signal SW, and an inspector unit for inspecting the dischargers on the basis of the electric signal SW; and a grounding terminal connecting a drive element of a discharger being inspected is electrically disconnected from another grounding terminal and a grounding line GL when the electric signal SW is detected by the detector.

Abstract: Crosstalk in a piezo printhead is reduced by storing a coefficient that expresses an amount of crosstalk between a first nozzle and an adjacent nozzle. A drive waveform voltage is pre-biased using the coefficient, and the pre-biased waveform is applied to a piezoelectric material of the first nozzle.

Abstract: In general, in one aspect, the invention features a method of driving an inkjet module having a plurality of ink jets. The method includes applying a voltage waveform to the inkjet module, the voltage waveform including a first pulse and a second pulse, activating one or more of the ink jets contemporaneously to applying the first pulse, wherein each activated ink jet ejects a fluid droplet in response to the first pulse, and activating all of the ink jets contemporaneously to applying the second pulse without ejecting a droplet.

Abstract: The number of head contacts, which increases along with an increase in the number of ink colors and nozzles used in a printhead and the length of the printhead, can be decreased. To accomplish this, a reception unit, which receives a serialized control parameter having an identification code indicating a normal drive pulse for discharging ink or a pulse short enough not to discharge ink, is arranged on the head substrate of a printhead. Further, a normal pulse generation unit, which generates the normal drive pulse based on a received control parameter, and a short pulse generation unit, which generates the short pulse based on a received control parameter, are arranged on the head substrate. Based on the identification code of the control parameter, it is controlled to output the normal drive pulse or short pulse.

Abstract: A method of controlling a liquid ejection head controls a liquid ejection head including a liquid pressurizing chamber, nozzles communicating with the liquid pressurizing chamber, and a pressure generating device that generates pressure in the liquid pressurizing chamber based on a drive waveform. The method includes generating a preliminary ejection drive waveform with a predetermined number of successive drive pulses aligned in descending order of length of drive pulse intervals of the drive pulses, with each of the drive pulse intervals set to an integral multiple of a natural vibration period of the liquid pressurizing chamber, and applying the generated preliminary ejection drive waveform to the pressure generating device to cause the liquid ejection head to perform a preliminary ejecting operation.

Abstract: A liquid ejecting device has a liquid ejecting head to eject ink to a sheet-like object, a carriage mounting the liquid ejecting head, a conveying device which conveys the sheet-like object with holding the sheet-like object to have a corrugated shape having a corrugated cross-section in the scanning direction, a detecting unit which detects an end portion of the sheet-like object in the scanning direction, and a processor. The processor is configured to execute instructions to provide an ejection timing determining unit configured to determine an ejection timing at which the liquid is ejected from the liquid ejecting head in accordance with positional information representing the end portion detected by the detecting unit and reference information, and an ejection control unit configured to control the liquid ejecting head and the carriage to eject the liquid from the liquid ejecting head at the timing determined by the ejection timing determining unit.

Abstract: According to one embodiment, a driving method of an ink jet head includes applying a first pulse for expanding volume of a pressure chamber in which an ink is accommodated to an actuator for applying oscillation to the pressure chamber and applying a second pulse for reducing volume of the pressure chamber to the actuator immediately before ink drops discharged from a nozzle which is communicated with the pressure chamber are separated from the nozzle.

Abstract: A device and a method for managing a piezo inkjet head. The device includes: a piezo actuator connected to an inkjet head to generate pressure; a driver that controls driving of the piezo actuator; a sensing resistor connected between the driver and the piezo actuator, a signal amplifier connected across the sensing resistor to amplify the signal applied to the sensing resistor; a signal processor that removes noise of the signal output from the signal amplifier; a controller that determines a signal passing through the signal processor as a reference signal in a state in which bubbles are not introduced into the inkjet head; and a storage unit that stores the signal determined as the reference signal in the controller. The controller calculates a difference between the signal passing through the signal processor and the reference signal to generate a detection signal and determine a state of the inkjet head.

Abstract: A drop emitting device that includes a drop generator and a drive signal waveform that includes in sequence a pulse of a first polarity, a first pulse of a second polarity, a delay interval, and a second pulse of the second polarity that includes a high frequency segment.

Abstract: After one ink of a white ink or a silver ink is ejected in a predetermined position of a recording medium such as a piece of recording paper to form a base layer, the other ink thereof is ejected on the base layer to form an intermediate layer, and a clear ink is ejected on the intermediate layer to form an epidermal layer.

Abstract: Methods, systems, and apparatus for drive a pumping chamber of a fluid ejection system are disclosed. In one implementation, the actuator for drive the pumping chamber includes a continuous piezoelectric layer between a pair of drive electrodes and a continuous reference electrode. The pair of drive electrodes includes an inner electrode and an outer electrode surrounding the inner electrode. The actuator is further coupled to a controller which, during a fluid ejection cycle, applies a negative voltage pulse differential to the outer electrode to expand the pumping chamber for a first time period, then applies another negative voltage pulse differential to the inner electrode during a second time period after the first time period to contract the pumping chamber to eject a fluid drop.

Abstract: A liquid droplet discharge head includes: a liquid chamber including an inner wall; a plurality of nozzles on a part of the inner wall; a diaphragm to change a pressure inside the liquid chamber; a piezoelectric element to displace the diaphragm; a drive voltage generator to generate a pulse voltage for normal driving; a micro-drive voltage generator to generate a pulse voltage for micro-driving; a voltage applying means to apply a voltage waveform including each pulse voltage to the piezoelectric element; and a nozzle activation ratio processor to calculate a nozzle activation ratio based on drive data for discharging liquid droplets from the nozzle. Based on the nozzle activation ratio, the micro-drive voltage generator generates a pulse voltage for the micro-driving including a peak voltage corresponding to the nozzle activation ratio, and the voltage applying means applies an appropriate voltage waveform to the piezoelectric element.

Abstract: A liquid ejecting apparatus includes a piezoelectric element, a nozzle that ejects a liquid in association with the driving of the piezoelectric element, a driving signal generation unit that generates a driving signal for driving a plurality of the piezoelectric elements, and a residual vibration detection unit that detects residual vibration generated by the driving of the piezoelectric element. The driving signal includes an ejection pulse for ejecting a liquid, a first vibration damping pulse that suppresses residual vibration generated by the ejection pulse, a second vibration damping pulse which is a pulse different from the first vibration damping pulse and suppresses residual vibration generated by the ejection pulse, and an inspection pulse for detecting the residual vibration signal.

Abstract: A liquid jet apparatus according to the present invention includes a drive waveform generator adapted to generate a drive waveform signal, a modulator adapted to execute pulse modulation on the drive waveform signal, a digital power amplifier adapted to power-amplify the modulated signal, on which the pulse modulation is executed by the modulator, with a pair of switching elements push-pull coupled with each other, a low pass filter adapted to smooth the amplified digital signal obtained by the power-amplification of the digital power amplifier, and a modulation period modification circuit adapted to modify a modulation period of the pulse modulation of the modulator based on data of the drive waveform signal.

Abstract: A resonance pulse is a voltage waveform substantially containing an expansion element for varying a voltage to expand a pressure chamber, an expansion sustaining element generated following with the expansion element, and sustaining a maximum voltage at a predetermined value, and a contraction element generated following with the expansion sustaining element, and varying the voltage to contract the pressure chamber. A time span from a front end of the expansion element to a front end of the contraction element is set as ½ of an inherent vibration cycle of ink in the pressure chamber.

Abstract: An image forming method for use in an inkjet head includes a pressure chamber filled with ink, a nozzle which communicates with the pressure chamber and in which a meniscus of the ink is formed, a piezoelectric element which pressurizes the pressure chamber, and a drive circuit which performs an operation of ejecting the ink in a printing state and generates a basic pulse for vibrating the meniscus in a non-printing state. The basic pulse is generated by turning off a voltage applied to the piezoelectric element for substantially the same period as a natural vibration period of the ink. An additional pulse is generated at least once before or after the basic pulse when the basic pulse is generated by the drive circuit in the non-printing state. The additional pulse is generated by turning off the voltage applied to the piezoelectric element.

Abstract: According to one embodiment, a driving apparatus of an inkjet head includes a drive signal output unit, an ejection pulse number decision unit, a pulse addition determination unit, and a drive signal generation unit. The ejection pulse number decision unit decides the number of ejection pulses based on a gradation value of print data. When the pulse addition determination unit has determined that the control pulse is not to be added, the drive signal generation unit generates a drive signal including ejection pulses whose number has been decided by the ejection pulse number decision unit. When the pulse addition determination unit has determined that the control pulse is to be added, the drive signal generation unit generates a drive signal including ejection pulses whose number is smaller than the number decided by the ejection pulse number decision unit.

Abstract: A method of driving a liquid ejection head adapted to apply a voltage to the liquid ejection head to eject a liquid including a polymer is provided. The method includes raising the voltage from a first voltage to a second voltage; raising the voltage from the second voltage to a third voltage at a gradient larger than that in raising the voltage from the first to the second voltage, and then holding the voltage at the third voltage; dropping the voltage from the third voltage to a fourth voltage, and then holding the voltage at the fourth voltage; raising the voltage from the fourth voltage to a fifth voltage, and then holding the voltage at the fifth voltage; dropping the voltage from the fifth voltage to a sixth voltage, and then holding the voltage at the sixth voltage; and raising the voltage from the sixth voltage to a seventh voltage.

Abstract: An image forming apparatus includes a recording head, a head driving control unit, and a dummy ejection control unit. The dummy ejection control unit controls first dummy ejection operation to eject droplets to a continuous medium per a constant length and second dummy ejection operation to eject droplets not contributing to image formation to an image formation area. In the first dummy ejection operation, the head driving control unit applies a first non ejection pulse to a pressure generator corresponding to a non ejection nozzle. In the second dummy ejection operation, the head driving control unit applies a second non ejection pulse to the pressure generator corresponding to the non ejection nozzle. When the second non ejection pulse is applied, an amplitude or number of vibrations of a meniscus of liquid in the non ejection nozzle is greater than when the first non ejection pulse is applied.

Abstract: A printer controller outputs plural drive signals including respective series of drive pulses, the timing points of which are different from one another, to a head control unit side, and outputs a multiplexed signal resulting from multiplexing change signals corresponding to the respective drive signals to a head control unit side, and the head control unit includes a control signal demultiplexing unit which demultiplexes the multiplexed signal into the change signals corresponding to respective nozzle rows, and an actuator control unit which, on the basis of each of the demultiplexed change signals, selects one of the drive pulses included in one of the drive signal which corresponds to the demultiplexed change signal, and applies the selected drive pulse to a piezoelectric element included in one of the nozzle rows which corresponds to the drive signal corresponding to the demultiplexed change signal.

Abstract: A liquid discharging apparatus is provided, which including: a pressure chamber communicating with a liquid supply portion and each nozzle; an element that performs an operation for providing change of pressure to liquid within the pressure chamber; and a pulse generating section that generates a pulse of which a voltage is changed to operate the element.

Abstract: An image forming apparatus comprises a printing head unit, a driving waveform generator that generates and outputs a driving waveform having four or more driving pulses in chronological order per driving cycle, and a selector that selects and applies one of multiple driving pulses to a pressure generator to cause a printing head unit to selectively discharge a liquid droplet of three or more different sizes. The driving waveform includes three or more driving pulses at least having a final driving pulse to collectively discharge the biggest liquid droplet. The driving waveform includes a micro-driving pulse for discharging a smallest droplet within a time period of from about 2×Tc to about 4×Tc after the driving waveform starts being outputted when Tc represents a natural vibration period of a separate liquid chamber of the printing head unit.

Abstract: A liquid ejecting apparatus includes a drive signal generation section which generates a drive signal and a liquid ejecting head. The drive signal is a periodic signal. One period of the drive signal has two durations of (i) a droplet ejection duration with a waveform part used to eject the droplet from the nozzle and (ii) a droplet non-ejection duration without the waveform part used to eject the droplet from the nozzle, and the droplet non-ejection duration is equal to or longer than the droplet ejection duration.