WO2004076180A1 - 液滴吐出装置及び液滴吐出ヘッドの吐出異常検出・判定方法 - Google Patents
液滴吐出装置及び液滴吐出ヘッドの吐出異常検出・判定方法 Download PDFInfo
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- WO2004076180A1 WO2004076180A1 PCT/JP2004/002390 JP2004002390W WO2004076180A1 WO 2004076180 A1 WO2004076180 A1 WO 2004076180A1 JP 2004002390 W JP2004002390 W JP 2004002390W WO 2004076180 A1 WO2004076180 A1 WO 2004076180A1
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- Prior art keywords
- droplet
- discharge
- ejection
- abnormality
- diaphragm
- Prior art date
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/135—Nozzles
- B41J2/14—Structure thereof only for on-demand ink jet heads
- B41J2/14314—Structure of ink jet print heads with electrostatically actuated membrane
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/015—Ink jet characterised by the jet generation process
- B41J2/04—Ink jet characterised by the jet generation process generating single droplets or particles on demand
- B41J2/045—Ink jet characterised by the jet generation process generating single droplets or particles on demand by pressure, e.g. electromechanical transducers
- B41J2/04501—Control methods or devices therefor, e.g. driver circuits, control circuits
- B41J2/0451—Control methods or devices therefor, e.g. driver circuits, control circuits for detecting failure, e.g. clogging, malfunctioning actuator
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/015—Ink jet characterised by the jet generation process
- B41J2/04—Ink jet characterised by the jet generation process generating single droplets or particles on demand
- B41J2/045—Ink jet characterised by the jet generation process generating single droplets or particles on demand by pressure, e.g. electromechanical transducers
- B41J2/04501—Control methods or devices therefor, e.g. driver circuits, control circuits
- B41J2/04541—Specific driving circuit
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/015—Ink jet characterised by the jet generation process
- B41J2/04—Ink jet characterised by the jet generation process generating single droplets or particles on demand
- B41J2/045—Ink jet characterised by the jet generation process generating single droplets or particles on demand by pressure, e.g. electromechanical transducers
- B41J2/04501—Control methods or devices therefor, e.g. driver circuits, control circuits
- B41J2/04578—Control methods or devices therefor, e.g. driver circuits, control circuits controlling heads based on electrostatically-actuated membranes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/015—Ink jet characterised by the jet generation process
- B41J2/04—Ink jet characterised by the jet generation process generating single droplets or particles on demand
- B41J2/045—Ink jet characterised by the jet generation process generating single droplets or particles on demand by pressure, e.g. electromechanical transducers
- B41J2/04501—Control methods or devices therefor, e.g. driver circuits, control circuits
- B41J2/0458—Control methods or devices therefor, e.g. driver circuits, control circuits controlling heads based on heating elements forming bubbles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/015—Ink jet characterised by the jet generation process
- B41J2/04—Ink jet characterised by the jet generation process generating single droplets or particles on demand
- B41J2/045—Ink jet characterised by the jet generation process generating single droplets or particles on demand by pressure, e.g. electromechanical transducers
- B41J2/04501—Control methods or devices therefor, e.g. driver circuits, control circuits
- B41J2/04581—Control methods or devices therefor, e.g. driver circuits, control circuits controlling heads based on piezoelectric elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
- B41J2/01—Ink jet
- B41J2/135—Nozzles
- B41J2/14—Structure thereof only for on-demand ink jet heads
- B41J2002/14411—Groove in the nozzle plate
Definitions
- the present invention relates to a droplet discharge device and a method for detecting and determining a discharge abnormality of a droplet discharge head.
- An ink jet printer which is one of the droplet discharge devices, forms an image on a predetermined sheet by discharging ink droplets (droplets) from a plurality of nozzles.
- the print head (ink-jet head) of an ink-jet printer has a large number of nozzles. May be clogged and ink drops cannot be ejected. If the nozzles are clogged, missing dots will occur in the printed image, which may cause deterioration in image quality.
- missing dot a state in which an ink droplet is not ejected from the nozzle of the ink jet head (an abnormal ink droplet ejection state) is detected.
- a method of optically detecting each nozzle of the nozzle has been devised (for example, Japanese Patent Application Laid-Open No. Hei 8-30963). With this method, it is possible to identify a nozzle that has a missing dot (discharge abnormality).
- a detector including a light source and an optical sensor is attached to a droplet ejection device (for example, an ink jet printer).
- a light source and a light source are arranged so that a droplet ejected from a nozzle of a droplet ejection head (ink jet head) passes between the light source and the optical sensor and blocks light between the light source and the optical sensor.
- Optical sensor with high precision high precision 2
- high precision 2 There is a problem that it must be set (installed).
- such a detector is usually expensive, and there is a problem that the manufacturing cost of the ink jet printer is increased.
- the output part of the light source and the detection part of the optical sensor may be contaminated by ink mist from the nozzles or paper dust of the printing paper, etc., and the reliability of the detector may become a problem.
- optical dot missing detection method it is possible to detect missing dots of nozzles, that is, abnormal ejection (non-ejection) of ink droplets, but based on the detection result, missing dots (abnormal ejection).
- missing dots abnormal ejection
- a droplet discharge device usually has a plurality of nozzles and corresponding nozzles.
- a droplet discharge device having a plurality of nozzles reduces the throughput of the device.
- the droplet discharge device of the present invention comprises:
- Discharge selection means for selecting which of the plurality of droplet ejection heads ejects a droplet from a nozzle of the droplet ejection head
- Discharge abnormality detecting means for detecting residual vibration of the diaphragm, and detecting abnormal discharge of droplets based on the detected vibration pattern of the residual vibration of the diaphragm;
- Switching means for switching the connection with the actuator from the drive circuit to the ejection abnormality detecting means after the droplet ejection operation by the actuator driving;
- the droplet discharge device With the droplet discharge device according to one embodiment of the present invention, it is possible to detect and determine the discharge abnormality of each nozzle of the droplet discharge head having a plurality of nozzles, and the circuit of such a droplet discharge device.
- the configuration can be scaled down, and an increase in the manufacturing cost can be prevented.
- the droplet discharge device of the present invention it is preferable that, for the plurality of droplet discharge heads, detection of the discharge abnormality of the droplets is performed one by one. As a result, it is possible to reliably detect and determine a discharge abnormality of all nozzles.
- a droplet discharge device of the present invention In another embodiment of the present invention, a droplet discharge device of the present invention
- a drive circuit for driving the actuator Discharge selection means for selecting which of the plurality of droplet ejection heads ejects a droplet from a nozzle of the droplet ejection head,
- a residual vibration of the diaphragm is detected in accordance with the droplet discharge head selected by the discharge selection means, and a droplet is detected based on the detected vibration pattern of the residual vibration of the diaphragm.
- connection with the actuator is connected from the driving circuit to the ejection abnormality detecting means corresponding to the actuator among the plurality of ejection abnormality detecting means.
- the droplet discharge device With the droplet discharge device according to another embodiment of the present invention, it is possible to execute the detection and determination processing of the discharge abnormality for each nozzle of the droplet discharge head having a plurality of nozzles at once, so that It is possible to detect and judge discharge abnormalities for all or arbitrary nozzles.
- the abnormal discharge of the droplet is detected for the plurality of droplet discharge heads substantially simultaneously. As a result, it is possible to reliably and quickly detect and determine the ejection abnormality of all nozzles in a short time.
- the switching means executes a switching operation based on an input of a predetermined switching signal (for example, a drive Z detection switching signal).
- the droplet discharge device of the present invention may further include a switching control unit that controls the switching unit corresponding to the droplet discharge head selected by the discharge selection unit to perform a switching operation.
- the switching control means includes a plurality of AND circuits arranged between the ejection selecting means and the respective switching means, corresponding to the plurality of switching means.
- a droplet discharge device of the present invention comprises:
- a diaphragm, an actuator for displacing the diaphragm, and a liquid filled therein A plurality of droplet discharges having: a cavity whose internal pressure is increased or decreased by the displacement of the vibration plate; and a nozzle which communicates with the cavity and discharges the liquid as droplets by increasing or decreasing the pressure in the cavity.
- Discharge selection means for selecting which of the plurality of droplet ejection heads ejects a droplet from a nozzle of the droplet ejection head
- Discharge abnormality detection means for detecting residual vibration of the diaphragm, and detecting abnormal discharge of liquid droplets based on the detected vibration pattern of the residual vibration of the diaphragm;
- Detection determination means for determining which of the plurality of nozzles the ejection abnormality detection means detects a droplet ejection abnormality
- the connection with the actuators is made by the driving circuit from the driving circuit.
- the droplet discharge device With the droplet discharge device according to the present embodiment, it is possible to more efficiently detect and determine a discharge abnormality with respect to the droplet discharge device according to the other embodiments. Further, in contrast to a droplet discharge device including a plurality of discharge abnormality detection units, the droplet discharge device of the present embodiment only needs to include one discharge abnormality detection unit, so that the circuit configuration can be scaled down. It is possible to prevent the manufacturing cost from increasing.
- the detection determining means includes: a switching selecting means for selecting which of the plurality of droplet discharge heads performs a switching operation of the switching means; Switching control means for controlling the switching means corresponding to the droplet discharge head selected by the selection means to perform a switching operation, the switching control means corresponding to the droplet discharge head determined by the detection determining means.
- the discharge abnormality detecting means may detect a discharge abnormality of the corresponding droplet discharge head.
- the detection determining means repeatedly performs a selection operation of sequentially selecting droplet discharge heads in a predetermined order from the plurality of droplet discharge heads, and the operation timing of the droplet discharge operation; At the time when the selection timing of the droplet discharge head coincides with the above, the droplet discharge head that coincides with the timing is determined as a droplet discharge head for detecting the abnormal discharge of the droplet. preferable.
- the discharge abnormality detection unit is configured to perform a droplet discharge operation in a flushing process of the nozzle to be detected or a droplet discharge operation in a printing operation. Abnormal discharge of droplets is detected at any of the timings.
- the droplet discharge device of the present invention can detect the abnormal discharge of the droplet even at the time of the printing (recording) operation, that is, the droplet discharge operation in the printing operation. Does not decrease or worsen.
- the residual vibration of the vibrating plate means that after the actuator performs a droplet discharge operation by a drive signal (voltage signal) of the drive circuit, the next drive signal is input and the droplet discharge operation is performed again. This means a state in which the diaphragm continues to vibrate while being attenuated by the droplet discharging operation until the step is performed.
- the discharge abnormality detection means includes a determination means for determining whether or not there is a discharge abnormality of the droplet discharge head based on a vibration pattern of residual vibration of the diaphragm.
- the determination unit determines the cause of the abnormal discharge.
- the vibration pattern of the residual vibration of the diaphragm may include a cycle of the residual vibration. This makes it possible to determine the cause of a droplet ejection abnormality that cannot be determined by a conventional device that can detect missing dots, such as an optical detection device. An appropriate recovery process can be selected and executed for the cause.
- the determination unit determines that the cycle of the residual vibration of the diaphragm is within a predetermined range. When the period is shorter than the period of the surroundings, it is determined that bubbles are mixed in the cavity. When the period of the residual vibration of the diaphragm is longer than a predetermined threshold, the liquid droplets near the nozzle thicken due to drying. Is determined. Further, preferably, the determination unit is configured such that when the cycle of the residual vibration of the diaphragm is longer than the cycle of the predetermined range and shorter than the predetermined threshold, paper dust is attached near the outlet of the nozzle. Is determined. In the present invention, “paper dust” is not limited to paper dust generated simply from recording paper or the like. For example, a piece of rubber such as a paper feed roller (feed roller) or air Anything that adheres to the vicinity of the nozzle, including debris that floats on the surface, and hinders droplet ejection.
- the droplet discharge device of the present invention may further include a storage unit that stores the determination result determined by the determination unit. This makes it possible to execute an appropriate recovery process at an appropriate time based on the stored determination result, for example, after the end of the printing operation.
- the discharge abnormality detecting means includes an oscillating circuit, and the oscillating circuit oscillates based on a capacitance component of the actuator that changes due to residual vibration of the diaphragm.
- the oscillation circuit may form a CR oscillation circuit that includes a capacitance component of the actuator and a resistance component of a resistance element connected to the actuator.
- the droplet discharge device of the present invention uses the residual vibration waveform (voltage waveform of the residual vibration) of the diaphragm as a time-series minute change of the capacitance component of the actuator (change of oscillation period). Since the detection is performed, the residual vibration waveform of the diaphragm can be accurately detected without depending on the magnitude of the electromotive force when the piezoelectric element is used for the entire operation.
- the oscillation frequency of the oscillation circuit is set to be higher than the oscillation frequency of the residual vibration of the diaphragm by about one digit or more.
- the oscillation frequency of the oscillation circuit is set to be higher than the oscillation frequency of the residual vibration of the diaphragm by about one digit or more.
- the discharge abnormality detecting means generates a voltage waveform of a residual vibration of the diaphragm using a predetermined signal group generated based on a change in an oscillation frequency in an output signal of the oscillation circuit. Including a conversion circuit.
- the discharge abnormality detection means includes a waveform shaping circuit for shaping a voltage waveform of the residual vibration of the diaphragm generated by the F / V conversion circuit into a predetermined waveform.
- the waveform shaping circuit includes a DC component removing means for removing a DC component from a voltage waveform of a residual vibration of the diaphragm generated by the F / V conversion circuit, and a DC component removing means.
- a comparator for comparing the voltage waveform from which the DC component has been removed with a predetermined voltage value, wherein the comparator generates and outputs a rectangular wave based on the voltage comparison;
- the discharge abnormality detecting means includes a measuring means for measuring a period of the residual vibration of the diaphragm from the rectangular wave generated by the waveform shaping circuit.
- the measuring means has a counter, and the counter counts a pulse of a reference signal, thereby measuring a time between a rising edge of the rectangular wave or a rising edge and a falling edge. You may. By measuring the period of the rectangular wave using the counter in this manner, the period of the residual vibration of the diaphragm can be detected more easily and more accurately.
- the actuation may be an electrostatic actuation or a piezoelectric actuation utilizing a piezoelectric effect of a piezoelectric element.
- the droplet discharge device of the present invention can use not only an electrostatic actuator composed of a capacitor as described above but also a piezoelectric actuator, the present invention can be applied to almost all existing droplet discharge devices. Can be applied.
- the droplet discharge device of the present invention includes an ink jet printer.
- Ejection selection means for selecting which nozzle of the droplet ejection head ejects a droplet
- Discharge abnormality detection means for detecting residual vibration of the diaphragm, and detecting abnormal discharge of liquid droplets based on the detected vibration pattern of the residual vibration of the diaphragm;
- Switching means for switching the connection with the actuator to the drive circuit or the discharge abnormality detection means
- Control means for controlling the discharge selection means
- control unit is configured to: select the nozzle of the droplet discharge head that performs droplet discharge or droplet discharge abnormality detection; and the switching unit according to a state of the drive circuit.
- the discharge selecting means is controlled based on a drive / detection switching signal for controlling the switching operation of the above.
- control means connects the actuator and the drive circuit when performing a discharge operation, and a drive signal output from the drive circuit when detecting abnormal discharge of a droplet. After a displacement operation is generated on the diaphragm by the method, the connection with the actuator is switched from the drive circuit to the discharge abnormality detecting means.
- a period during which the switching unit connects the actuator to the discharge abnormality detecting unit is between the drive signal and the drive signal, that is, within a drive suspension period.
- the discharge abnormality detection means detects the discharge abnormality for the nozzle selected by the discharge selection means.
- the nozzles selected by the ejection selection means scan one by one nozzles of the droplet ejection head, and scan the nozzles before the droplet ejection head. The discharge abnormality may be detected.
- the droplet discharge device of the present invention may be provided with a plurality of the discharge abnormality detecting means and a plurality of the switching means respectively corresponding to a plurality of nozzles.
- all the nozzles of the droplet discharge head are selected by the discharge selection unit, and the discharge abnormality is simultaneously detected for all the nozzles.
- the droplet ejection apparatus of the present invention selects a plurality of the switching units synchronized with the plurality of nozzles selected by the ejection selection unit, and performs a switching for inputting the driving Z detection switching signal.
- the apparatus may further include a control unit, and may be configured to simultaneously detect the discharge abnormality for a plurality of nozzles selected by the discharge selection unit.
- a plurality of switching means respectively corresponding to a plurality of nozzles, and a switching selection means for arbitrarily selecting the switching means and inputting the drive Z detection switching signal may be provided.
- the switching selection unit may be configured to select the switching units one by one based on a scanning signal output from the control unit so as to go around the plurality of switching units.
- the switching selection unit is executed in synchronization with a timing of a nozzle selected by the ejection selection unit.
- an output of the switching selection unit is input to the switching control unit, and the driving / detection is performed by the switching unit based on a logical product of a selection result of the switching selection unit and a selection result of the switching control unit.
- a switching signal may be input, and the discharge abnormality detecting means corresponding to the switching means may be configured to detect the discharge abnormality.
- the discharge abnormality detection means detects the discharge abnormality at any timing of a droplet discharge operation in a flushing process of the nozzle to be detected or a droplet discharge operation in a printing operation. Be composed.
- a droplet discharge device of the present invention In another embodiment of the present invention, a droplet discharge device of the present invention
- a plurality of droplet ejection heads having an actuator and a diaphragm that is displaced by driving the actuator, and ejecting the liquid in the cavity as droplets from the nozzle by the driving of the actuator.
- Discharge abnormality detecting means for detecting residual vibration of the diaphragm, and detecting abnormal discharge of droplets based on the detected vibration pattern of the residual vibration of the diaphragm;
- a droplet discharge device comprising:
- n (where n is a natural number) droplet discharge heads are defined as one block, and m (where m is a natural number) blocks are provided;
- each ejection abnormality detection means is assigned to the predetermined block.
- each of the ejection abnormality detecting means sequentially detects the ejection abnormality for the n droplet ejection heads in the assigned block. It is characterized by performing.
- the detection and determination of the discharge abnormality are performed during the flushing process, so that no special time is required for the detection and determination of the discharge abnormality, and the efficiency is improved.
- the consumption of liquid such as ink can be minimized, and it is possible to detect and determine the discharge abnormality of each nozzle of the droplet discharge head having a plurality of nozzles.
- the number of times of droplet discharge (n times) matches the number of droplet discharge heads in one block (n), and the same number (m) of discharge abnormality detecting means as blocks are provided. Therefore, it is possible to reliably detect and judge the abnormal discharge of the nozzles one by one by discharging the liquid droplets n times, and to reduce the number of the abnormal discharge detecting means. As a result, the circuit configuration can be scaled down and an increase in manufacturing cost can be prevented.
- the droplet discharging apparatus of the present invention preferably, after the droplet discharging operation by the driving of the actuator, the connection with the reactor is switched from the driving circuit to the discharging abnormality detecting means. Having means.
- the apparatus further includes a determination unit configured to determine whether or not the droplet discharge head has abnormal discharge based on a vibration pattern of residual vibration of the diaphragm. Preferably, when it is determined that the droplet discharge head has an abnormal discharge of the droplet, the determining unit determines the cause of the abnormal discharge.
- the determination means determines that air bubbles are mixed in the cavity, and the cycle of the residual vibration of the diaphragm Is longer than a predetermined threshold, it is determined that the liquid in the vicinity of the nozzle has thickened due to drying, and the cycle of the residual vibration of the diaphragm is longer than the cycle of the predetermined range, and is greater than the predetermined threshold. Is shorter, it is determined that paper dust has adhered to the vicinity of the outlet of the nozzle. This makes it possible to determine the cause of a droplet ejection abnormality that cannot be determined by a conventional device that can detect missing dots, such as an optical detection device, and, if necessary, An appropriate recovery process can be selected and executed for the cause.
- the detection of the discharge abnormality performed by discharging the droplet n times is performed periodically.
- the state of the nozzles of each droplet discharge head can be maintained in a good state, and the discharge abnormality of each nozzle can be periodically detected and determined.
- the detection of the discharge abnormality performed by discharging the droplet n times is performed each time the droplet discharge head reciprocates.
- the state of the nozzles of each droplet discharge head can be maintained in a good state, and the discharge abnormality of each nozzle can be detected and determined each time the droplet discharge head reciprocates.
- the detection of a discharge abnormality performed by discharging the droplet n times is performed immediately after the power of the droplet discharge device is turned on.
- the nozzles of each droplet discharge head can be reliably brought into a good state, and the discharge abnormality of each nozzle is detected and determined. be able to.
- the recovery means detects the discharge abnormality performed by discharging the droplet n times. Immediately after the recovery processing by. Thus, immediately after the recovery processing is executed, the nozzles of each droplet discharge head can be reliably brought into a good state, and the discharge abnormality of each nozzle can be detected and determined.
- a method for detecting and determining a discharge abnormality of a droplet discharge head includes any one of a plurality of droplet discharge heads each having a diaphragm, an actuator, and a nozzle.
- the driving circuit for driving the actuator is switched to a detecting circuit.
- the detecting circuit the residual vibration of the diaphragm is detected, and the detected residual vibration of the diaphragm is detected. It is characterized by detecting a drop ejection abnormality based on the vibration pattern.
- a plurality of the detection circuits are provided corresponding to the plurality of droplet discharge heads, respectively, and after the droplet discharge operation, the connection of the actuator is connected from the drive circuit to the actuator. Switch to the corresponding detection circuit.
- the switching operation from the drive circuit to the detection circuit may be executed only for the selected droplet discharge head.
- an arbitrary droplet discharge head of the plurality of droplet discharge heads is designated, and the switching operation is performed on the designated arbitrary droplet discharge head.
- the abnormal discharge of the droplet is detected at a timing of a droplet discharge operation in a flushing process of the nozzle to be detected or a droplet discharge operation of a printing operation.
- the cause of the discharge abnormality is determined.
- the vibration pattern of the residual vibration is a period of the residual vibration, and when the detected period of the residual vibration is shorter than a predetermined range, the droplet is regarded as a cause of the ejection abnormality. Judges that air bubbles have entered the ejection head cavity.
- the period of the detected residual vibration is longer than a predetermined threshold, it is determined that the liquid near the nozzle of the droplet discharge head has increased in viscosity due to drying as a cause of the discharge abnormality, and the detection is performed.
- the cycle of the residual vibration is longer than the cycle of the predetermined range and shorter than the predetermined threshold, paper droplets are deposited near the nozzle outlet of the droplet ejection head as a cause of the ejection abnormality. Is determined.
- the determination result determined in the determination may be stored in the storage unit.
- FIG. 1 is a schematic view showing a configuration of an ink jet printing apparatus which is a kind of the droplet discharge device of the present invention.
- FIG. 2 is a block diagram schematically showing a main part of the ink jet printing of the present invention.
- FIG. 3 is a schematic cross-sectional view of one ink jet head in the head unit shown in FIG.
- FIG. 4 is an exploded perspective view showing a schematic configuration corresponding to one color ink of the head unit of FIG.
- FIG. 5 is an example of a nozzle arrangement pattern of a nozzle plate of a head unit using four-color inks.
- FIG. 6 is a state diagram showing each state when a drive signal is input in the III-III cross section of FIG.
- FIG. 7 is a circuit diagram showing a simple vibration calculation model assuming residual vibration of the diaphragm shown in FIG.
- FIG. 8 is a graph showing the relationship between the experimental value and the calculated value of the residual vibration of the diaphragm in FIG. 3.
- FIG. 9 is a conceptual diagram of the vicinity of the nozzle when bubbles are mixed in the cavity in FIG. 10 is a graph showing a calculated value and an experimental value of the residual vibration in a state where the ink droplets are not ejected due to air bubbles entering the cavity.
- FIG. 11 is a conceptual diagram of the vicinity of the nozzle when the ink near the nozzle of FIG. 3 is fixed by drying.
- FIG. 12 is a graph showing calculated values and experimental values of residual vibration in a state where the ink near the nozzles is in a dry and thickened state.
- FIG. 13 is a conceptual diagram of the vicinity of the nozzle when paper dust adheres near the nozzle outlet of FIG.
- FIG. 14 is a graph showing calculated values and experimental values of the residual vibration in a state where paper dust adheres to the nozzle outlet.
- FIG. 15 is a photograph showing the state of the nozzle before and after the paper dust adheres to the vicinity of the nozzle.
- FIG. 16 is a schematic block diagram of the discharge abnormality detecting means shown in FIG.
- FIG. 17 is a conceptual diagram in the case where the electrostatic factor of FIG. 3 is a parallel plate capacitor.
- FIG. 18 is a circuit diagram of an oscillator circuit including a capacitor composed of the electrostatic function shown in FIG.
- FIG. 19 is a circuit diagram of the F / V conversion circuit of the ejection abnormality detecting means shown in FIG.
- FIG. 20 is a timing chart showing timings such as output signals of each unit based on the oscillation frequency output from the oscillation circuit of the present invention.
- FIG. 21 is a diagram for explaining a method of setting the fixed times tr and t1.
- FIG. 22 is a circuit diagram showing a circuit configuration of the waveform shaping circuit of FIG.
- FIG. 23 is a block diagram schematically showing switching means for switching between the drive circuit and the detection circuit.
- FIG. 24 is a flowchart showing the discharge abnormality detection / determination processing of the present invention.
- FIG. 25 is a flowchart showing the residual vibration detection processing of the present invention.
- FIG. 26 is a flowchart showing the discharge abnormality determination processing of the present invention.
- FIG. 27 shows an example of the timing of detecting the ejection abnormality of a plurality of inkjet heads (when there is one ejection abnormality detection unit).
- Fig. 28 shows an example of the timing of detecting abnormal discharge of multiple inkjet heads (discharge timing). (When the number of output abnormality detecting means is the same as the number of ink jet heads).
- Fig. 29 shows an example of the timing of detecting abnormal ejection of multiple ink jet heads (when the number of ejection abnormality detecting means is the same as the number of ink jet heads and the abnormal ejection is detected when there is print data). It is.
- FIG. 30 shows an example of the timing of detecting the ejection failure of a plurality of inkjet heads (when the number of ejection failure detection means is the same as the number of ink jet heads and the ejection failure detection is performed by circulating through each ink jet head). ).
- FIG. 31 is a flowchart showing the timing of detecting a discharge abnormality during the flushing operation of the ink jet printer shown in FIG.
- FIG. 32 is a flowchart showing the timing of detecting a discharge abnormality during the flushing operation of the ink jet printing shown in FIGS. 28 and 29.
- FIG. 33 is a flowchart showing the timing of detecting an ejection abnormality during the flushing operation of the ink jet printing shown in FIG.
- FIG. 34 is a flowchart showing the timing of ejection failure detection during the printing operation of the ink jet printing shown in FIGS. 28 and 29.
- FIG. 35 is a flowchart showing the timing of detecting an ejection failure during the printing operation of the ink jet printing shown in FIG.
- FIG. 36 is a diagram showing a schematic structure (a part is omitted) of the inkjet printer shown in FIG. 1 as viewed from above.
- FIG. 37 is a diagram showing a positional relationship between the wiper shown in FIG. 36 and the head unit.
- FIG. 38 is a diagram showing the relationship between the inkjet head, the cap, and the pump during the pump suction process.
- FIG. 39 is a schematic diagram showing the configuration of the tube pump shown in FIG.
- FIG. 40 is a front chart showing the ejection failure recovery process in the ink jet printing of the present invention.
- FIG. 41 is a cross-sectional view schematically showing another configuration example of the ink jet head according to the present invention.
- FIG. 42 is a cross-sectional view schematically showing another example of the configuration of the ink jet head according to the present invention.
- FIG. 43 is a cross-sectional view schematically showing another configuration example of the ink jet head according to the present invention.
- FIG. 44 is a cross-sectional view schematically showing another configuration example of the ink jet head according to the present invention. '
- FIG. 45 is a block diagram showing a main part of a droplet discharge device according to a third embodiment of the present invention.
- FIG. 46 is a block diagram of one block of the droplet discharge device shown in FIG.
- FIG. 47 is a perspective view showing another configuration example of the head unit in the present invention.
- FIG. 48 is a schematic sectional view of the head unit shown in FIG.
- FIG. 49 is a plan view showing an example of a nozzle arrangement pattern in a head unit nozzle plate using four color inks.
- FIG. 1 is a schematic diagram showing a configuration of an ink jet printer 1 which is a kind of a droplet discharge device according to a first embodiment of the present invention.
- the upper side in FIG. 1 is referred to as “upper”, and the lower side is referred to as “lower”.
- the configuration of the ink jet printer 1 will be described.
- the ink jet printer 1 shown in FIG. A tray 21 on which the recording paper P is placed, a paper discharge roller 22 for discharging the recording paper P in the lower front, and an operation panel 7 on the upper surface are provided.
- the operation panel 7 includes, for example, a liquid crystal display, an organic EL display, an LED lamp, and the like, and includes a display unit (not shown) for displaying an error message and the like, and an operation unit (not shown) including various switches. Zu).
- a printing apparatus (printing means) 4 having a reciprocating printing means (moving body) 3 and a paper feeder ( (Paper feeding means) 5 and a control unit (control means) 6 for controlling the printing device 4 and the paper feeding device 5.
- the paper feeding device 5 intermittently feeds the recording paper P one by one.
- This recording paper P passes near the lower part of the printing means 3.
- the printing means 3 reciprocates in a direction substantially orthogonal to the feed direction of the recording paper P, and printing on the recording paper P is performed. That is, the reciprocating movement of the printing means 3 and the intermittent feeding of the recording paper P become main scanning and sub-scanning in printing, and ink jet printing is performed.
- the printing device 4 reciprocates the printing means 3 in response to the rotation of the printing means 3, the carriage motor 41 serving as a driving source for moving the printing means 3 in the main scanning direction, and the carriage motor 41. And a reciprocating mechanism 42.
- the printing means 3 has a plurality of head units 35 corresponding to the type of ink having a large number of nozzles 110, and a plurality of ink cartridges (I ZC) for supplying ink to each head unit 35 at its lower part. And a carriage 32 on which each head unit 35 and an ink cartridge 31 are mounted.
- each of the head units 35 includes one nozzle 110, a diaphragm 121, an electrostatic actuator 120, a cavity 144, and ink. It has a large number of ink jet recording heads (ink-jet heads or droplet discharge heads) 100 constituted by supply ports 144 and the like.
- the head unit 35 has a configuration including the ink cartridge 31 in FIG. 1, it is not limited to such a configuration. For example, fix ink cartridge 31 separately, and It may be supplied to the head unit 35 by a heater or the like. Therefore, in the following, apart from the printing means 3, one nozzle 110, a vibrating plate 121, an electrostatic actuator 120, a cavity 144, and an ink supply port are respectively provided.
- a head provided with a plurality of ink jet heads 100 constituted by 14 2 and the like is referred to as a head unit 35.
- an ink cartridge 31 filled with ink of four colors of yellow, cyan, magenta, and black (black) full-color printing can be performed.
- the printing unit 3 is provided with a head unit 35 corresponding to each color.
- FIG. 1 shows four ink cartridges 31 corresponding to the four color inks, but the printing means 3 uses other colors such as light cyan, light magenta, and dark yellow.
- the ink cartridge 31 may be further provided.
- the reciprocating mechanism 42 includes a carriage guide shaft 42 2 having both ends supported by a frame (not shown), and a timing belt 42 1 extending in parallel with the carriage guide shaft 42. Have.
- the carriage 32 is reciprocally supported by a carriage guide shaft 42 of the reciprocating mechanism 42 and is fixed to a part of the timing belt 42 1.
- the printing means 3 is guided by the carriage guide shaft 422 to reciprocate. During this reciprocating movement, ink is ejected from the nozzles 110 of the plurality of ink jet heads 100 in the head unit 35 as appropriate in accordance with the image data (print data) to be printed. The printing on the recording paper P is performed.
- the paper feeding device 5 has a paper feeding motor 51 serving as a driving source thereof, and a paper feeding port roller 52 rotated by the operation of the paper feeding motor 51.
- the paper feed roller 52 is composed of a driven roller 52 a and a drive port roller 52 b that are vertically opposed to each other across the feed path (recording paper P) of the recording paper P, and the drive roller 52 b is It is connected to the paper feeder 51.
- the paper feed rollers 52 are set on tray 21 A large number of recording papers P can be sent one by one toward the printing device 4.
- a configuration in which a paper cassette for storing the recording paper P can be detachably mounted may be used.
- the control unit 6 controls the printing device 4 and the sheet feeding device 5 based on print data input from a host computer 8 such as a personal computer (PC) or a digital camera (DC), thereby controlling the recording paper P. Print processing.
- the control unit 6 displays an error message or the like on the display unit of the operation panel 7 or turns on an LED lamp or the like, blinks Z, and inputs various switch pressing signals input from the operation unit. , And causes each unit to execute a corresponding process.
- FIG. 2 is a block diagram schematically showing a main part of the ink jet printer of the present invention.
- the inkjet printer 1 of the present invention includes an interface unit (IF) 9 for receiving a print data input from a host computer 8, a control unit 6, a carriage motor 41, a carriage motor driver 43 for driving and controlling the carriage motor 41, a paper feeding motor 51, a paper feeding motor driver 53 for driving and controlling the paper feeding motor 51, and a head unit. 35, a head driver 33 for driving and controlling the head unit 35, and a discharge abnormality detecting means 10.
- IF interface unit
- the ejection abnormality detection means 10 the recovery means 24, and the head driver 33 will be described later.
- the control unit 6 receives input from a CPU (Central Processing Unit) 61 for executing various processes such as printing process and ejection abnormality detection / judgment process, and an IF 9 from a host computer 8.
- EEPROM Electrical Erasable Programmable Read-Only Memory
- storage means 62, which is a type of non-volatile semiconductor memory for storing printing data in a data storage area (not shown), and a discharge device described later.
- RAM Random Access Memory
- PROM 64 which is a kind of nonvolatile semiconductor memory for storing a control program and the like for controlling.
- Each component of the control unit 6 is a bus (not shown). Connected electrically through the
- the printing unit 3 includes a plurality of head units 35 corresponding to the respective color inks.
- Each of the head units 35 includes a plurality of nozzles 110 and a plurality of these nozzles 110. It has a corresponding electrostatic actuator 120 and (a plurality of inkjet heads 100). That is, the head unit 35 is provided with a plurality of ink jet heads (droplet discharge heads) 100 each having a set of nozzles 110 and an electrostatic actuator 120. It has a configuration.
- the head driver 33 drives the electrostatic actuator 120 of each ink jet head 100 to control the ink ejection timing, and the switching circuit 23 controls the driving circuit 18. (See Figure 16). The configurations of the inkjet head 100 and the electrostatic actuator 120 will be described later.
- control unit 6 is electrically connected to various sensors that can detect the remaining amount of ink in the ink cartridge 31, the position of the printing unit 3, the printing environment such as temperature and humidity, and the like. Have been.
- control unit 6 When the control unit 6 obtains print data from the host computer 8 via the IF 9, the control unit 6 stores the print data in the EPROM 62. Then, the CPU 61 executes a predetermined process on the print data, and outputs a drive signal to each of the drivers 33, 43, 53 based on the processed data and input data from various sensors. I do. When these drive signals are input via each of the dryinos 33, 43, 53, the electrostatic actuator 120 corresponding to the plurality of inkjet heads 100 of the head unit 35, printing is performed. The carriage module 41 of the device 4 and the paper feeder 5 are operated. Thus, the printing process is performed on the recording paper P.
- FIG. 3 is a schematic cross-sectional view (including common parts such as the ink cartridge 31) of one inkjet head 100 in the head unit 35 shown in FIG. 2, and FIG.
- FIG. 5 is an exploded perspective view showing a schematic configuration of a head unit 35 corresponding to FIG. 5, and FIG. 5 is a head to which a plurality of the ink jet heads 100 shown in FIG. 3 are applied.
- FIG. 6 is a plan view illustrating an example of a nozzle surface of a unit 35. 3 and 4 are shown upside down from the state of normal use, and FIG. 5 is a plan view of the inkjet head 100 shown in FIG. 3 when viewed from above in the figure. It is.
- the head unit 35 is connected to the ink cartridge 31 via an ink inlet 131, a damper chamber 130, and an ink supply tube 311.
- the damper chamber 130 is provided with a damper 132 made of rubber.
- the damper chamber 130 can absorb the fluctuation of the ink and the change of the ink pressure when the carriage 32 reciprocates, thereby providing the ink unit 100 of the head unit 35 with the ink. A fixed amount of ink can be supplied stably.
- the head unit 35 has a silicon nozzle 140 on the upper side with the silicon substrate 140 interposed therebetween, and a borosilicate glass substrate (glass substrate) on the lower side having a thermal expansion coefficient close to that of silicon. 16 have a three-layer structure in which they are stacked.
- the central silicon substrate 140 has a plurality of independent cavities (pressure chambers) 14 1 (seven cavities are shown in Fig. 4) and one reservoir (common ink chamber) 144. Grooves are formed to function as ink supply ports (orifices) 142 for communicating the reservoirs 144 with the cavities 144, respectively. Each groove can be formed, for example, by performing an etching process from the surface of the silicon substrate 140.
- the nozzle plate 150, the silicon substrate 140, and the glass substrate 160 are joined in this order, and the cavities 144, the reservoirs 144, and the ink supply ports 144 are partitioned and formed. ing.
- Each of these cavities 14 1 is formed in a rectangular shape (a rectangular parallelepiped shape), and its volume is variable by the vibration (displacement) of a diaphragm 121 described later, and the nozzle (ink nozzle) is changed by this volume change. It is configured to eject ink (liquid material) from 110.
- nozzles 110 are formed at positions corresponding to the distal end portions of the cavities 141, and these are communicated with the cavities 141, respectively.
- an ink inlet 131 which communicates with the reservoir 144, is formed in a portion of the glass substrate 160 where the reservoir 144 is located.
- the ink is The ink is supplied from the ink cartridge 3 1 to the reservoir 1 3 4 through the ink supply tube 3 1 1, the damper chamber 1 30, and the ink inlet 1 3 1.
- the ink supplied to the reservoirs 144 is supplied to the independent cavities 144 through the respective ink supply ports 142.
- Each cavity 144 is defined by a nozzle plate 150, side walls (partition walls) 144, and a bottom wall 121.
- Each of the independent cavities 1 4 1 has its bottom wall 1 2 1 formed to be thin, and its bottom wall 1 2 1 is elastically deformed in its out-of-plane direction (thickness direction), that is, in the vertical direction in FIG. It is configured to function as a diaphragm (diaphragm) that can be shaped (elastically displaced). Therefore, this portion of the bottom wall 121 may be referred to as a diaphragm 122 for convenience of the following description (that is, in the following, both the “bottom wall” and the “diaphragm”) will be described.
- the sign 1 2 1 is used).
- shallow recesses 16 1 are formed at positions corresponding to the cavities 14 1 of the silicon substrate 140.
- the bottom wall 12 1 of 14 1 is opposed to the surface of the opposite wall 16 2 of the glass substrate 160 in which the recess 16 1 is formed, with a predetermined gap therebetween. That is, a gap having a predetermined thickness (for example, about 0.2 ⁇ m) exists between the bottom wall 121 of the cavity 144 and a segment electrode 122 described later.
- the recess 161 can be formed, for example, by etching or the like.
- the bottom wall (diaphragm) 1 2 1 of each of the cavities 1 4 1 is a common electrode 1 2 4 on the side of each of the cavities 1 4 1 for storing electric charges by a drive signal supplied from the head driver 3 3.
- each of the diaphragms 121 of each of the captives 141 also serves as one of the counter electrodes (counter electrodes of the capacitors) of the corresponding electrostatic actuator 120 described later.
- a segment electrode which is an electrode opposed to the common electrode 124 so as to face the bottom wall 121 of each cavity 141 is provided. 1 2 2 is formed.
- each fire The bottom wall 1 2 1 of the tee 1 41, that is, the diaphragm 1 2 1 and the corresponding segment electrodes 1 2 2 are the lower wall in FIG. 3 of the bottom wall 1 2 1 of the cavity 1 4 1
- a counter electrode (a counter electrode of the capacitor) is formed (configured) through the insulating layer 123 formed on the surface and the void in the recess 161. Therefore, the main part of the electrostatic actuator 120 is constituted by the diaphragm 121, the segment electrode 122, the insulating layer 123 and the gap therebetween.
- a head driver 33 including a drive circuit 18 for applying a drive voltage between these counter electrodes is provided according to a print signal (print data) input from the control unit 6. Charge and discharge between these opposed electrodes is performed.
- One output terminal of the head driver (voltage applying means) 33 is connected to each segment electrode 122, and the other output terminal is an input terminal of the common electrode 124 formed on the silicon substrate 140. Connected to 1 2 4a. Since the silicon substrate 140 has impurities implanted therein and has conductivity, the input terminal 124 a of the common electrode 124 is connected to the common electrode 122 of the bottom wall 122. 4 can supply voltage.
- a thin film of a conductive material such as gold or copper may be formed on one surface of the silicon substrate 140.
- a voltage (charge) can be supplied to the common electrode 124 with low electric resistance (efficiently).
- This thin film may be formed by, for example, vapor deposition or sputtering.
- the silicon substrate 140 and the glass substrate 160 are bonded (bonded) by positive electrode bonding, so that the conductive film used as an electrode in the anodic bonding is formed of the silicon substrate 140. It is formed on the flow channel forming surface side (the upper side of the silicon substrate 140 shown in FIG. 3). Then, this conductive film is used as it is as the input terminal 124 a of the common electrode 124.
- the input terminal 124 a of the common electrode 124 may be omitted, and the bonding method between the silicon substrate 140 and the glass substrate 160 is limited to anodic bonding. Not done.
- the head unit 35 includes a nozzle plate 150 on which a plurality of nozzles 110 corresponding to the plurality of inkjet heads 100 are formed, a plurality of cavities 141, and a plurality of nozzles.
- Ink supply port 1 4 2 and one reservoir 1 4 3 It has a recon substrate (ink chamber substrate) 140 and an insulating layer 123, which are housed in a substrate 170 including a glass substrate 160.
- the substrate 170 is made of, for example, various resin materials, various metal materials, and the like, and the silicon substrate 140 is fixed and supported on the substrate 170.
- the plurality of nozzles 110 formed on the nozzle plate 150 are linearly arranged substantially in parallel with the reservoirs 144 in FIG. 4 for simplicity in FIG.
- the arrangement pattern of 10 is not limited to this configuration, and is usually arranged in a staggered manner, for example, as in a nozzle arrangement pattern shown in FIG. Further, the pitch between the nozzles 110 can be appropriately set according to the printing resolution (dpi).
- FIG. 5 shows an arrangement pattern of the nozzles 110 when four color inks (ink cartridges 31) are applied.
- FIG. 6 shows each state at the time of driving signal input in the III-III section of FIG.
- a driving voltage is applied between the opposing electrodes from the head driver 33
- a Coulomb force is generated between the opposing electrodes, and the bottom wall (diaphragm) 1 2 1 is moved with respect to the initial state (FIG. 6 (a)).
- the segment electrode 122 bends to the side, and the capacity of the cavity 141 increases (FIG. 6 (b)).
- the diaphragm 122 is restored upward in the figure by its elastic restoring force, and the diaphragm in the initial state is restored.
- the diaphragm 1 2 1 of each cavity 1 4 1 receives the next drive signal (drive voltage) by this series of operations (ink ejection operation by the drive signal of the head driver 3 3) and ejects ink droplets again. Until then, it is damping.
- this damped vibration is also referred to as residual vibration.
- the residual vibration of the diaphragm 1 2 1 includes the acoustic resistance r due to the shape of the nozzle 110 and the ink supply port 144 or the ink viscosity, etc., the inertance m due to the ink weight in the flow path, and the diaphragm 1 2 Fixed value determined by 1 compliance Cm It is assumed to have a vibrating frequency.
- FIG. 7 is a circuit diagram showing a simple vibration calculation model assuming residual vibration of diaphragm 122.
- the calculation model of the residual vibration of the diaphragm 122 can be expressed by the sound pressure P, the above-mentioned inertia m, the compliance Cm, and the acoustic resistance r. Then, when the step response when the sound pressure P is applied to the circuit in FIG. 7 is calculated for the volume velocity u, the following equation is obtained.
- FIG. 8 is a graph showing the relationship between the experimental value and the calculated value of the residual vibration of diaphragm 122. As can be seen from the graph shown in Fig. 8, the two waveforms, the experimental value and the calculated value, generally match.
- the abnormal discharge of the droplet may be simply referred to as “missing dot”.
- the dot missing (discharge abnormality) phenomenon (abnormal discharge phenomenon) during the printing process that occurs in the nozzle 110 of the ink jet head 100 is classified according to the cause. Adjust the values of acoustic resistance r and Z or inertance m so that the calculated value of the residual vibration of diaphragm 1 21 and the experimental value match (approximately match). Here, three types of air bubbles, dry thickening, and paper dust adhesion are examined.
- FIG. 9 is a conceptual diagram of the vicinity of the nozzle 110 when bubbles B are mixed in the cavity 14 1 of FIG. As shown in FIG. 9, it is assumed that the generated bubble B is generated and adhered to the wall surface of the cavity 144. (In FIG. 9, the bubble B This shows the case where it is attached near the nozzle 110).
- the bubbles B are mixed in the cavity 141, it is considered that the total weight of the ink filling the cavity 141 decreases, and the inertia m decreases.
- the bubble B is attached to the wall of the cavity 141, it is thought that the diameter of the nozzle 110 becomes larger by the size of the diameter, and the acoustic resistance r decreases.
- FIG. 11 is a conceptual diagram of the vicinity of the nozzle 110 when the ink near the nozzle 110 of FIG. 3 is fixed by drying. As shown in FIG. 11, when the ink near the nozzle 110 is dried and fixed, the ink in the cavity 141 is in a state where it is trapped in the cavity 141. Thus, when the ink near the nozzle 110 is dried and thickened, it is considered that the acoustic resistance r increases.
- the acoustic resistance r was set to be large and matched with the experimental value of the residual vibration at the time of ink drying and sticking (thickening) near the nozzle 110.
- the result (graph) shown in Fig. 12 was obtained.
- the head unit 35 was left unattended for several days without a cap (not shown), and the ink near the nozzle 110 in the cavity 141 dried and thickened. This is a measurement of the residual vibration of the diaphragm 122 in a state where the ink can no longer be ejected (the ink is fixed).
- FIG. 13 is a conceptual diagram of the vicinity of the nozzle 110 when paper powder adheres to the vicinity of the nozzle 110 exit of FIG. As shown in Fig. 13, if paper dust adheres to the vicinity of the outlet of nozzle 110, ink exudes from inside cavity 141 via the paper dust, and ink is discharged from nozzle 110. Discharge becomes impossible.
- FIG. 15 is a photograph showing the state of the nozzle 110 before and after the adhesion of the paper powder.
- the frequency of the damped vibration is low.
- a predetermined threshold value is set in the frequency, cycle, and phase of the damped vibration. They can be compared with each other or can be specified from the decay rate of the period change or amplitude change of the residual vibration (damped vibration).
- a change in the residual vibration of the diaphragm 121 when an ink droplet is ejected from the nozzle 110 in each of the ink jet heads 100 causes a change in each ink jet head.
- An ejection abnormality of 100 can be detected.
- the cause of the ejection abnormality can be specified.
- FIG. 16 is a schematic block diagram of the ejection abnormality detecting means 10 shown in FIG.
- the output abnormality detection means 10 is a residual vibration detection means 16 comprising an oscillation circuit 11, an F / V conversion circuit 12 and a waveform shaping circuit 15 and is detected by the residual vibration detection means 16
- the residual vibration detecting means 16 oscillates the oscillation circuit 11 based on the residual vibration of the diaphragm 121 of the electrostatic actuator 120, and calculates the F The / V conversion circuit 12 and the waveform shaping circuit 15 form and detect a vibration waveform. Then, the measuring means 17 measures the cycle of the residual vibration based on the detected vibration waveform, and the determining means 20 determines the respective cycles in the head unit 35 based on the measured cycle of the residual vibration. Abnormal ejection of ink jet 100 is detected and judged.
- each component of the ejection abnormality detection means 10 will be described.
- FIG. 17 is a conceptual diagram in the case where the electrostatic actuator 120 of FIG. 3 is a parallel plate capacitor, and FIG. 18 is a capacitor composed of the electrostatic actuator 120 of FIG.
- FIG. 2 is a circuit diagram of an oscillation circuit 11 including the above.
- the oscillation circuit 11 shown in FIG. 18 is a CR oscillation circuit that uses the hysteresis characteristic of the Schmitt trigger, the present invention is not limited to such a CR oscillation circuit. Any oscillation circuit may be used as long as the oscillation circuit uses a capacitor (including a capacitor).
- the oscillation circuit 11 may be configured to use, for example, an LC oscillation circuit.
- a Schmitt trigger is described, a CR oscillation circuit using three stages of invertors may be configured, for example.
- This electrostatic actuator 120 can be considered as a parallel plate capacitor as shown in FIG.
- X in Expression (4) indicates the displacement amount of the diaphragm 122 from the reference position caused by the residual vibration of the diaphragm 121, as shown in FIG.
- the capacitance C (x) increases, and conversely, the gap length g (gap length g—displacement X) As the quantity X) increases, the capacitance C (X) decreases.
- the capacitance C (X) is inversely proportional to (gap length g—displacement X) (gap length g if X is 0).
- the relative permittivity is 1 because the air gap is filled with air.
- the size of the discharged ink droplets becomes smaller. Will be denser and smaller.
- the surface area S of the diaphragm 121 of the ink jet head 100 becomes smaller, and a small electrostatic actuator 120 is formed.
- the gap length g of the electrostatic actuator 120 which changes due to residual vibration caused by ink droplet ejection, is the initial gap g. Therefore, as can be seen from Eq. (4), the amount of change in the capacitance of the electrostatic actuator 120 is a very small value.
- the amount of change in capacitance of this electrostatic actuator 120 The following method is used to detect the oscillating signal: an oscillating circuit as shown in Fig. 18 based on the capacitance of the electrostatic actuator 120 is constructed, and based on the oscillated signal, Use a method of analyzing the frequency (period) of the residual vibration using
- the oscillation circuit 11 shown in Fig. 18 is composed of a capacitor (C) composed of an electrostatic actuator 120, a Schmitt trigger inverter 111, and a resistance element (R) 112. Be composed. When the output signal of the Schmitt trigger inverter is at the Hig level, the capacitor C is charged through the resistor element.
- the oscillation frequency of the oscillation circuit 11 is The oscillation frequency must be set so that the frequency of the residual vibration, which is the highest when bubbles are mixed (see Fig. 10), can be detected. Therefore, the oscillation frequency of the oscillation circuit 11 must be, for example, several times to several tens times or more of the frequency of the residual vibration to be detected, that is, a frequency that is about one digit or more higher than the frequency when bubbles are mixed. .
- the CR time constant of the oscillation circuit 11 is set according to the oscillation frequency. As described above, by setting the oscillation frequency of the oscillation circuit 11 high, it is possible to prevent the oscillation frequency from minutely changing. Based on this, a more accurate residual vibration waveform can be detected.
- the count pulse is counted using a count pulse (counter) for measurement, and the initial gap g.
- a count pulse (counter) for measurement By subtracting the pulse count of the oscillation frequency when oscillating with the capacitance of the capacitor C in the above from the measured count, digital information for each oscillation frequency for the residual vibration waveform can be obtained. By performing digital / analog (D / A) conversion based on these digital information, a rough residual vibration waveform can be generated.
- a count pulse (counter) for measurement needs to have a high frequency (high resolution) capable of measuring a small change in the oscillation frequency.
- Such a count pulse (counter) uses the F / V conversion circuit 12 shown in FIG. 19 in the ejection abnormality detecting means 10 of the present invention in order to increase the cost.
- FIG. 19 is a circuit diagram of the FZV conversion circuit 12 of the ejection abnormality detection means 10 shown in FIG.
- the F / V conversion circuit 12 includes three switches SW1, SW2, and SW3, two capacitors C1 and C2, a resistance element R1, and a constant current I It comprises a constant current source 13 that outputs s and a buffer 14.
- the operation of the FZV conversion circuit 12 will be described with reference to the timing chart of FIG. 20 and the graph of FIG. First, a method of generating the charge signal, the hold signal, and the clear signal shown in the timing chart of FIG. 20 will be described.
- the charging signal is generated such that a fixed time tr is set from the rising edge of the oscillation pulse of the oscillation circuit 11 and the High level is maintained during the fixed time tr.
- the hold signal rises in synchronization with the rising edge of the charge signal, is held at the high level for a predetermined fixed time, and is generated so as to fall to the low level.
- the clear signal rises in synchronization with the falling edge of the hold signal, is held at the high level for a fixed time, and falls at the low level.
- the transfer of charge from the capacitor C1 to the capacitor C2 and the discharge of the capacitor C1 are performed instantaneously, so that the pulses of the hold signal and the clear signal correspond to the output signal of the oscillation circuit 11.
- the method of setting the fixed times tr and t1 will be described with reference to Fig. 21 to obtain a clean residual vibration waveform (voltage waveform).
- the fixed time tr is 120
- the initial gap length is 120 g. It is adjusted from the period of the oscillation pulse oscillated by the capacitance C at the time of, and the charging potential by the charging time t1 is set to be about 1/2 of the charging range of C1.
- the output constant current Is of the constant current source 13 may be set to an appropriate value.
- the output constant current Is of this constant current source 13 as high as possible within the range, a minute change in the capacitance of the capacitor constituted by the electrostatic actuator 120 can be reduced.
- the sensitivity can be detected, and a minute change of the diaphragm 121 of the electrostatic actuator 120 can be detected.
- FIG. 22 is a circuit diagram showing a circuit configuration of the waveform shaping circuit 15 of FIG.
- the waveform shaping circuit 15 outputs the residual vibration waveform to the determination means 20 as a rectangular wave.
- the waveform shaping circuit 15 includes two capacitors C 3 (DC component removing means) and C 4, two resistance elements R 2 and R 3, and two DC voltage sources V ref 1, V ref 2, amplifier (operational amplifier) 15 1, and comparator 15 2.
- the detected peak value may be output as it is to measure the amplitude of the residual vibration waveform.
- the output of the buffer 14 of the F / V conversion circuit 12 has an initial gap g of the electrostatic actuator 120.
- the DC component (DC component) of the capacitance is included. Since the DC component varies depending on each ink jet head 100, the capacitor C3 removes the DC component of the capacitance. And the capacitor C 3 removes the DC component in the output signal of the buffer 14 and outputs only the AC component of the residual vibration to the inverting input terminal of the operational amplifier 15 1.
- the operational amplifier 151 inverts and amplifies the output signal of the buffer 14 of the F / V conversion circuit 12 from which the DC component has been removed, and constitutes a low-pass filter for removing a high band of the output signal. It is assumed that the operational amplifier 151 is a single power supply circuit.
- the operational amplifier 151 constitutes an inverting amplifier composed of two resistance elements R2 and R3, and the input residual vibration (AC component) is amplified by -R3 / R2 times. ''
- the residual vibration of the amplified vibration plate 121 oscillating around the potential set by the DC voltage source Vref 1 connected to its non-inverting input terminal A waveform is output.
- the DC voltage source Vref1 is set to about 1/2 of the voltage range in which the operational amplifier 151 can operate with a single power supply. Further, the operational amplifier 151 forms a low-pass filter having a cutoff frequency of 1 / (27TXC4XR3) by the two capacitors C3 and C4. Then, as shown in the timing chart of FIG. 20, the residual vibration waveform of the diaphragm 121 amplified after removing the DC component is supplied to another DC voltage source by the next-stage comparator (comparator) 152. It is compared with the potential of Vref2, and the comparison result is output from the waveform shaping circuit 15 as a rectangular wave. It should be noted that the DC voltage source Vref1 may share another DC voltage source Vref1.
- the F / V conversion circuit 12 shown in FIG. 19 operates based on the charging signal, the clear signal, and the hold signal generated as described above.
- the diaphragm 1 21 of the actuator 120 is attracted to the segment electrode 122 side, and rapidly contracts upward in FIG. 6 in synchronization with the falling edge of the drive signal of ⁇ (FIG. 6 (c) See).
- the drive circuit 18 and ejection abnormality detection means In synchronization with the falling edge of this drive signal, the drive circuit 18 and ejection abnormality detection means The drive / detection switching signal for switching to 10 becomes High level.
- This drive Z detection switching signal is held at the High level during the drive suspension period of the corresponding ink jet head 100, and goes to the Low level before the next drive signal is input. While the drive Z detection switching signal is at the High level, the oscillation circuit 11 in FIG. 18 oscillates while changing the oscillation frequency in response to the residual vibration of the diaphragm 121 of the electrostatic actuator 120.
- the switch SW1 When the fixed time tr has elapsed and the charging signal goes low, the switch SW1 is turned on in synchronization with the falling edge of the charging signal (see FIG. 19). Then, the constant current source 13 is connected to the capacitor C1, and the capacitor C1 is charged with the gradient Is s / Cl as described above. The capacitor C1 is charged while the charge signal is at the Low level, that is, until the output signal of the oscillation circuit 11 goes to the High level in synchronization with the rising edge of the next pulse.
- the switch SW1 When the charge signal becomes High level, the switch SW1 is turned off (open), and the constant current source 13 and the capacitor C1 are disconnected. At this time, the capacitor C1 stores the potential charged during the low-level period t1 of the charge signal (that is, ideally, Isxt1 / C1 (V)). In this state, when the hold signal becomes High level, the switch SW2 is turned on (see FIG. 19), and the capacitor C1 and the capacitor C2 are connected via the resistance element R1. After the connection of switch SW2, charging and discharging are performed by the charging potential difference between the two capacitors C1 and C2, and the capacitor C1 is connected from the capacitor C1 so that the potential difference between the two capacitors C1 and C2 becomes substantially equal.
- the capacitance of capacitor C2 is about 1 with respect to the capacitance of capacitor C1.
- Zl is set to about 0 or less. Therefore, the amount of charge that moves (used) due to charge and discharge caused by the potential difference between the two capacitors C1 and C2 is less than 1/10 of the charge stored in the capacitor C1. Therefore, even after the charge is transferred from the capacitor C1 to the capacitor C2, the potential difference of the capacitor C1 does not change so much (it does not decrease so much).
- the resistance is set so that the charging potential does not jump up due to the inductance of the wiring of the F / V conversion circuit 12 or the like.
- the element R 1 and the capacitor C 2 form the primary mouth-to-pass fill.
- the hold signal becomes low level, and the capacitor C1 is disconnected from the capacitor C2. Further, when the clear signal becomes the High level and the switch SW3 is turned on, the capacitor C1 is connected to the ground GND, and the discharging operation is performed so that the charge stored in the capacitor C1 becomes zero. After the discharge of the capacitor C1, the clear signal goes to the low level, and when the switch SW3 is turned off, the upper electrode of the capacitor C1 in FIG. 19 is disconnected from the ground GND until the next charge signal is input. In other words, it waits until the charging signal goes low.
- the potential held in the capacitor C 2 is updated at each rising timing of the charging signal, that is, at each timing of completing the charging of the capacitor C 2, and is represented as a residual vibration waveform of the diaphragm 121 via the buffer 14.
- Output to 22 waveform shaping circuit 15. Therefore, the capacitance of the electrostatic actuator 120 (in this case, the fluctuation range of the capacitance due to the residual vibration must be taken into consideration) and the resistance value of the resistance element 112 so that the oscillation frequency of the oscillation circuit 11 increases.
- each step (step) of the potential of the capacitor C2 (output of the buffer 14) shown in the timing chart of FIG. 20 becomes more detailed, so that the capacitance of the capacitance due to the residual vibration of the diaphragm 121 is increased. It is possible to detect temporal changes in more detail.
- the charging signal changes from low level to high level ⁇ low level ' ⁇ '.
- the potential held in the capacitor C2 is repeatedly output to the waveform shaping circuit 15 via the buffer 14 at the above-mentioned predetermined timing.
- the DC component of the voltage signal (the potential of the capacitor C 2 in the timing chart of FIG. 20) input from the buffer 14 is removed by the capacitor C 3, and the operational amplifier is connected to the operational amplifier via the resistor R 2. ,, 15 1 Input to the inverted input terminal.
- the input alternating current (AC) component of the residual vibration is inverted and amplified by the operational amplifier 151, and output to one input terminal of the comparator 152.
- the comparator 1502 compares the potential (reference voltage) preset by the DC voltage source V ref 2 with the potential of the residual vibration waveform (AC component) and outputs a square wave (see FIG. 20). The output of the comparison circuit in the timing chart of FIG.
- FIG. 23 is a block diagram schematically showing the switching means 23 for switching between the drive circuit 18 and the discharge abnormality detection means 10.
- the drive circuit 18 in the head driver 33 shown in FIG. 16 will be described as a drive circuit for the inkjet head 100.
- the ejection abnormality detection / determination processing of the present invention is performed between the drive signals of the inkjet head 100, that is, during the drive suspension period. .
- the switching means 23 is initially connected to the drive circuit 18 in order to drive the electrostatic actuator 120.
- a drive signal voltage signal
- the electrostatic actuator 120 is driven, and the diaphragm 122 is connected to the segment electrode.
- the applied voltage becomes 0, it is suddenly displaced away from the segment electrode 122 and starts vibrating (residual vibration).
- ink droplets are ejected from the nozzles 110 of the inkjet head 100.
- a drive / detection switching signal (see the timing chart in FIG. 20) is input to the switching means 23 in synchronization with the falling edge, and the switching means 23 outputs the drive circuit 1 Discharge abnormality detection means (detection circuit) can be switched from 10 to 10 side
- the electrostatic actuator 120 (used as a capacitor of the oscillation circuit 11) is connected to the discharge abnormality detecting means 10.
- the ejection abnormality detection means 10 executes the above-described ejection abnormality detection (dropout of dot) detection / determination processing, and executes the processing of the diaphragm 12 1 output from the comparator 15 2 of the waveform shaping circuit 15.
- the residual vibration waveform data (rectangular wave data) is quantified by the measuring means 17 into the period and amplitude of the residual vibration waveform.
- the measuring means 17 measures a specific vibration cycle from the residual vibration waveform data, and outputs the measurement result (numerical value) to the judging means 20.
- the measuring means 17 measures the time from the first rising edge of the waveform (rectangular wave) of the output signal of the comparator 152 to the next rising edge (period of the residual vibration). Using a counter (not shown), the pulse of the reference signal (predetermined frequency) is counted, and the period of the residual vibration (specific vibration period) is measured from the count value. Note that the measuring means 17 measures the time from the first rising edge to the next falling edge, and outputs a time twice as long as the measured time to the determining means 20 as the cycle of the residual vibration. Good.
- the cycle of the residual vibration obtained in this manner is referred to as Tw.
- the determining means 20 determines whether there is a nozzle discharge abnormality, the cause of the discharge abnormality, the amount of comparison deviation, etc., based on the specific vibration period (measurement result) of the residual vibration waveform measured by the measuring means 17. Then, the determination result is output to the control unit 6.
- the control unit 6 stores this determination result in a predetermined storage area of the EEPROM (storage means) 62. Then, at the timing when the next drive signal from the drive circuit 18 is input, the drive / detection switching signal is input again to the switching means 23, and the drive circuit 18 and the electrostatic actuator 120 are connected. Connecting.
- the drive circuit 18 maintains the ground (GND) level once the drive voltage is applied, so that the above-described switching is performed by the switching means 23 (see the timing chart of FIG. 20).
- the residual vibration waveform data is not limited to a rectangular wave generated by the comparator 152.
- the residual vibration amplitude data output from the operational amplifier 15 1 is digitized from time to time by the A / D conversion measuring means 17 without performing the comparison process by the comparator 15 2, and is digitized.
- the determination means 20 may determine whether or not there is a discharge abnormality, and the determination result may be stored in the storage means 62.
- the meniscus of the nozzle 110 (the surface where the ink in the nozzle 110 comes into contact with the atmosphere) vibrates in synchronization with the residual vibration of the diaphragm 121, so that the inkjet head 100 ejects ink droplets.
- the next ejection operation is performed.
- the residual vibration of the diaphragm 121 is detected by effectively utilizing the waiting time, it is possible to detect a discharge abnormality which does not affect the driving of the ink jet head 100. That is, it is possible to execute the ejection abnormality detection / determination process of the nozzle 110 of the ink jet 100 without reducing the throughput of the ink jet printer 1 (droplet ejection device).
- the frequency becomes higher than the residual vibration waveform of the diaphragm 122 at the time of normal ejection.
- the cycle is shorter than the cycle of the residual vibration during normal ejection.
- the residual vibration is over-attenuated, and the frequency becomes considerably lower than the residual vibration waveform during normal ejection. The period is much longer than the period of the residual vibration during normal ejection.
- the frequency of the residual vibration is lower than the frequency of the residual vibration during normal ejection, but is lower than the frequency of the residual vibration during drying of the ink. Therefore, the period is longer than the period of the residual vibration during normal ejection and shorter than the period of the residual vibration during ink drying.
- a predetermined range T r is set as the period of the residual vibration during normal ejection, and the period of the residual vibration when paper dust adheres to the outlet of the nozzle 110 and the nozzle 1 11
- a predetermined threshold value (predetermined threshold value) T 1 in order to distinguish the period of the residual vibration when the ink dries near the exit of 0, such an ink jet head 10
- the cause of the ejection abnormality of 0 can be determined.
- the determination means 20 determines whether or not the cycle Tw of the residual vibration waveform detected by the above-described discharge abnormality detection / determination processing is a cycle in a predetermined range, and whether or not the cycle is longer than a predetermined threshold value. Then, the cause of the discharge abnormality is determined.
- FIG. 24 is a flowchart showing the discharge abnormality detection / determination processing of the present invention.
- the discharge abnormality detection / determination process corresponding to the discharge operation of one ink head 100, that is, one nozzle 110, is performed.
- a drive signal corresponding to print data is input from the drive circuit 18 of the head driver 33, and thereby, based on the timing of the drive signal as shown in the timing chart of FIG.
- a drive signal (voltage signal) is applied between both electrodes of the electrical equipment 120 (step S101).
- the control unit 6 determines whether or not the ejected inkjet head 100 is in the drive suspension period based on the drive Z detection switching signal (step S102).
- the drive Z detection switching signal becomes High level in synchronization with the falling edge of the drive signal (see FIG. 20), and is input from the control unit 6 to the switching means 23.
- the switching means 23 disconnects the electrostatic actuator 120, that is, the capacitor constituting the oscillation circuit 11 from the drive circuit 18.
- the discharge abnormality detecting means 10 detection circuit
- the measuring means 17 measures a predetermined numerical value from the residual vibration waveform data detected in the residual vibration detection processing (step S104).
- the measuring unit 17 measures the cycle of the residual vibration from the residual vibration waveform data.
- the determination means 20 performs a discharge abnormality determination process, which will be described later, based on the measurement result of the measurement means (step S 106), and stores the determination result in an EEPROM (storage means) 6 2 of the control unit 6. Is stored in a predetermined storage area (step S107). Then, in step S108, it is determined whether or not the inkjet head 100 is in the drive period. That is, it is determined whether or not the next drive signal has been input after the end of the drive suspension period, and the process stands by at step S108 until the next drive signal is input.
- step S108 At the timing when the pulse of the next drive signal is input, when the drive Z detection switching signal goes low in synchronization with the rising edge of the drive signal (“yes” in step S108), the switching means 23 Then, the connection with the electrostatic actuator 120 is switched from the discharge abnormality detection means (detection circuit) 10 to the drive circuit 18 (step S109), and the discharge abnormality detection / determination processing is completed. .
- the flowchart shown in FIG. 24 shows a case where the measuring means 17 measures the period from the residual vibration waveform detected by the residual vibration detection processing (residual vibration detecting means 16).
- the measuring unit 17 may measure the phase difference and the amplitude of the residual vibration waveform from the residual vibration waveform data detected in the residual vibration detection processing.
- FIG. 25 is a flowchart showing the residual vibration detection processing of the present invention.
- the oscillation circuit 11 is connected to the CR oscillation circuit. And oscillates based on the change in capacitance of the electrostatic actuator 120 (residual vibration of the diaphragm 121 of the electrostatic actuator 120). Step S201).
- a charge signal, a hold signal, and a clear signal are generated in the F / V conversion circuit 12 based on the output signal (pulse signal) of the oscillation circuit 11, and these signals are generated.
- the FZV conversion circuit 12 converts the frequency of the output signal of the oscillation circuit 11 into a voltage based on the FZV conversion circuit 12 (step S202), and the diaphragm from the F / V conversion circuit 12 1 2 1 residual vibration waveform data is output.
- the DC component DC component
- the capacitor C 3 of the waveform shaping circuit 15 step S 203
- the operational amplifier 15 1 The residual vibration waveform (AC component) from which the DC component has been removed is amplified (step S204).
- the residual vibration waveform data after the amplification is shaped into a pulse by a predetermined process and is converted into a pulse (step S205). That is, in the present embodiment, the comparator 152 compares the voltage value (predetermined voltage value) set by the DC voltage source Vref2 with the output voltage of the operational amplifier 151. The comparator 152 outputs a binarized waveform (rectangular wave) based on the comparison result. The output signal of the comparator 152 is an output signal of the residual vibration detecting means 16 and is output to the measuring means 17 to perform the discharge abnormality determination processing, and the residual vibration detecting processing ends.
- the comparator 152 compares the voltage value (predetermined voltage value) set by the DC voltage source Vref2 with the output voltage of the operational amplifier 151.
- the comparator 152 outputs a binarized waveform (rectangular wave) based on the comparison result.
- the output signal of the comparator 152 is an output signal of the residual vibration detecting means 16 and is output to the measuring means 17
- FIG. 26 is a flowchart showing a discharge abnormality determination process executed by the control unit 6 and the determination unit 20 of the present invention.
- the judging means 20 determines whether or not the ink droplet has been normally ejected from the corresponding ink jet head 100 based on the measurement data (measurement result) such as the cycle measured by the measuring means 17 described above. If the discharge is not normal, that is, if the discharge is abnormal, determine the cause.
- the control unit 6 outputs the predetermined range Tr of the period of the residual vibration and the predetermined threshold T1 of the period of the residual vibration stored in the EEPROM 62 to the determination means 20.
- the predetermined range Tr of the period of the residual vibration is determined to be normal with respect to the period of the residual vibration during normal ejection. It has a tolerable tolerance. These data are stored in a memory (not shown) of the determination means 20, and the following processing is executed.
- the measurement result measured by the measuring means 17 in step S105 of FIG. 24 is input to the judging means 20 (step S301).
- the measurement result is the period Tw of the residual vibration of the diaphragm 122.
- step S302 the determination means 20 determines whether or not the residual vibration period Tw exists, that is, whether or not the discharge abnormality detection means 10 has not obtained residual vibration waveform data. If it is determined that the period Tw of the residual vibration does not exist, the determination means 20 determines that the nozzle 110 of the inkjet head 100 has detected an ejection failure and has not ejected an ink droplet in the determination process. It is determined that the nozzle is a non-ejection nozzle (step S306). When it is determined that the residual vibration waveform data exists, subsequently, in step S303, the determination means 20 determines that the cycle Tw is within a predetermined range Tr in which the cycle Tw is recognized as a cycle during normal ejection. Is determined.
- the determining means 20 determines that the period Tw of the residual vibration is the predetermined period. Is determined to be shorter than the range Tr.
- the determination means 20 determines that air bubbles are mixed in the cavity 14 1 of the inkjet head 100 (bubble mixing) ( Step S308).
- the determining means 20 determines whether the period Tw of the residual vibration is longer than the predetermined threshold T1. It is determined whether or not it is (step S305). When it is determined that the period Tw of the residual vibration is longer than the predetermined threshold T1, it is considered that the residual vibration is excessively damped, and the determination means 20 determines whether the nozzle of the inkjet head 100 It is determined that the ink around 110 is thickened by drying (dry) (step S309).
- step S305 when it is determined that the cycle Tw of the residual vibration is shorter than the predetermined threshold T1, the cycle Tw of the residual vibration satisfies Tr ⁇ Tw ⁇ Tl As described above, it is considered that paper dust adheres to the vicinity of the outlet of the nozzle 110 having a higher frequency than that of drying, and the determination means 20 determines the ink jet head 100 It is determined that paper dust is attached near the nozzle 110 outlet (paper dust attached) (step S3110).
- the determination unit 20 determines the normal ejection or the cause of the ejection abnormality of the target inkjet head 100 (steps S306 to S310), the determination result is as follows.
- the output is output to the control unit 6, and the discharge abnormality determination processing ends.
- an ink jet printer 1 including a plurality of ink jet heads (droplet ejection heads) 100 that is, a head unit 35 having a plurality of nozzles 110 (in the present embodiment,
- the head unit 3 5 includes five ink jet heads 100 a to 100 e (i.e., five nozzles 110).
- the number of the ink jet heads 100 (nozzles 110) provided in each head unit 35 is not limited to this, and may be any number.
- FIGS. 27 to 30 are block diagrams showing some examples of ejection abnormality detection / judgment timing in the ink jet printer 1 including the plurality of ejection selecting means 18.
- the configuration example of each drawing will be sequentially described.
- FIG. 27 shows an example of the timing of detecting a discharge abnormality of a plurality of ink jet heads 100 (when there is one discharge abnormality detection means 100).
- the ink jet printer 1 having the ink jet heads 100 a to 100 e has a driving waveform generating means 18 1 for generating a driving waveform, and which nozzle 110 ejects an ink droplet.
- the configuration other than the above is the same as that shown in FIG. 2, FIG. 16 and FIG.
- the drive waveform generation means 18 1 and the ejection selection means 18 2 are described as being included in the drive circuit 18 of the head driver 33 (in FIG. 27, the switching means 23 1 Are shown as two blocks, but in general, both are configured in the head driver 33).
- the present invention is not limited to this configuration.
- the drive waveform generating means 18 1 Alternatively, the configuration may be independent of the head driver 33.
- the ejection selection means 18 2 includes a shift register 18 2 a, a latch circuit 18 2 b, and a driver 18 2 c.
- each output signal of the shift register Latch the signal.
- the output signal of the latched shift register 18a becomes 0 (latch output is stopped), and the printing operation is stopped.
- the print data of the latched shift register 18a is output to the driver 18c.
- the next print data is input to the shift register 18 2a, and the latch circuit is synchronized with the print timing.
- the 18 2 b latch signal is sequentially updated.
- the driver 18 c connects the drive waveform generating means 18 1 to the electrostatic actuator 120 of each ink jet head 100, and outputs from the latch circuit 18 b.
- Latch signal specified (specified) by each electrostatic actuator 120 any or all of the inkjet heads 100 0 a to l 0 e
- the output signal (drive signal) of the drive waveform generating means 18 1 is input, and the drive signal (voltage signal) is applied between both electrodes of the electrostatic actuator 120.
- the ink jet printer 1 shown in FIG. 27 includes one driving waveform generating means 18 1 for driving a plurality of ink jet heads 100 a to 100 e, and each of the ink jet heads 100 a to 100 e.
- Ejection failure detecting means 10 for detecting ejection failure (non-ejection of ink droplets) to any one of the ink jet heads 100 and the cause of the ejection failure obtained by this ejection failure detection means 10
- Storage means 62 for storing (storing) the determination result of the above, and one switching means 23 for switching between the drive waveform generation means 18 1 and the ejection abnormality detection means 10.
- the ink jet printer 1 has one or more ink jet heads 100 selected by the driver 18 c based on the drive signal input from the drive waveform generating means 18 1.
- the switching means 23 is driven from the driving waveform generation means 18 1 to the ejection abnormality detection means 10 by the inkjet head 100.
- the ejection failure detecting means 10 detects the ink jet head 1 based on the residual vibration waveform of the diaphragm 121. This is to detect a discharge abnormality (non-discharge of ink droplets) at the nozzle 110 of 00 and determine the cause of the discharge abnormality in the case of discharge abnormality.
- the ink jet printer 1 detects and determines a discharge abnormality with respect to the nozzle 110 of one ink jet head 100, it then performs the following based on the drive signal input from the drive waveform generator 18 1.
- a discharge abnormality is detected and determined for the nozzle 110 of the ink jet head 100 specified in the above, and similarly, the ink jet head driven by the output signal of the driving waveform generating means 18 1 Discharge abnormalities for the 0 nozzle 110 are sequentially detected and determined.
- the measuring means 17 measures the period of the residual vibration waveform based on the waveform data.
- the determination means 20 determines, based on the measurement result of the measurement means 17, whether the discharge is normal or abnormal, and in the case of discharge abnormality (head abnormality), the cause of the discharge abnormality. And outputs the result of the determination.
- the ejection abnormality is sequentially detected in the ink droplet ejection driving operation for each of the nozzles 110 of the plurality of ink jet heads 100a to 100e. Since it is configured to detect and judge, it is only necessary to provide one ejection abnormality detection means 10 and one switching means 23, and the circuit configuration of the inkjet printer 1 that can detect and judge ejection abnormality can be scaled down. At the same time, an increase in the manufacturing cost can be prevented.
- FIG. 28 shows an example of the timing of detecting the ejection failure of the plurality of ink jet heads 100 (when the number of ejection failure detection means 100 is the same as the number of the inkjet heads 100).
- the ink jet printer 1 shown in FIG. 28 includes one ejection selecting means 18 2, five ejection abnormality detecting means 10 a to 10 e, five switching means 23 a to 23 e, It has one drive waveform generating means 18 1 common to the five inkjet heads 100 a to 100 e, and one storage means 62. Since each component has already been described in the description of FIG. 27, the description thereof will be omitted, and the connection thereof will be described.
- the ejection selection means 18 2 Based on the input print data (discharge data) and the clock signal CLK, the print data corresponding to each of the ink jet heads 100a to 100e is latched by the latch circuit 182, and the drive waveform generation means 181 outputs the driver data. In accordance with the drive signal (voltage signal) inputted to 182c, the electrostatic actuator 120 of the inkjet head 100a to 100e corresponding to the printing data is driven.
- the drive Z detection switching signal is input to the switching units 23a to 23e corresponding to all the ink jet heads 100a to 100e, respectively, and the switching units 23a to 23e output the corresponding print data ( Irrespective of the presence or absence of ejection data), after inputting a drive signal to the electrostatic actuator 120 of the ink jet head 100 based on the drive Z detection switching signal, the drive waveform generation means 181 and the ejection abnormality detection means 10a to 10 Switch the connection with ink jet head 100 to e.
- All the ejection abnormality detection means 10a to 10e detect and judge the ejection abnormality of each ink jet 100a to 100e, and then detect and judge the ejection abnormality.To all the ink jets obtained in the judgment process
- the determination results of the ink jet heads 100a to 100e are output to the storage unit 62, and the storage unit 62 stores the presence / absence of the ejection abnormality of each of the inkjet heads 100a to 100e in the predetermined storage area. I do.
- a plurality of ejection abnormality detecting means 10 a to 10 e are provided corresponding to the respective nozzles 110 of the plurality of ink jet heads 100 a to 100 e.
- the switching operation is performed by a plurality of switching means 23a to 23e corresponding thereto, and the discharge abnormality is detected and its cause is determined.
- the cause can be determined.
- FIG. 29 shows an example of the timing of detecting the ejection failure of the plurality of ink jet heads 100 (the number of the ejection failure detection means 10 is the same as the number of the ink jet heads 100, and the ejection failure detection is performed when there is print data. If you do).
- the ink jet printer 1 shown in FIG. 29 is obtained by adding (adding) switching control means 19 to the configuration of the ink jet printer 1 shown in FIG.
- the switching control means Reference numeral 19 denotes a plurality of AND circuits (logical product circuits) ANDa to ANDe.
- a high-level output signal is output to the corresponding switching means 23a to 23e.
- the switching control means 19 is not limited to an AND circuit (logical product circuit), but is configured so that the switching means 23 corresponding to the output of the latch circuit 182b from which the inkjet head 100 to be driven is selected is selected. Just fine.
- Each of the switching means 23 a to 23 e is connected to the corresponding discharge abnormality detecting means 10 a to 10 e from the drive waveform generating means 181 based on the output signal of the corresponding AND circuit ANDa to ANDe of the switching control means 19. The connection between the corresponding inkjet heads 100a to 100e and the electrostatic actuator 120 is switched.
- the switching means 23a to 23e corresponding to the AND circuit outputs the corresponding ink jet head 100a to The connection to 100 e is switched from the drive waveform generation means 181 to the discharge abnormality detection means 10 a to 10 e.
- the discharge abnormality detection means 10 After detecting the presence or absence of an ejection failure of the inkjet head 100 and the cause of the ejection failure by the ejection failure detection means 10a to 10e corresponding to the ink jet head 100 to which the print data is input, The discharge abnormality detection means 10 outputs the determination result obtained in the discharge abnormality detection / determination processing to the storage means 62.
- the storage means 62 stores one or a plurality of determination results (obtained) input (obtained) in this manner in a predetermined storage area.
- a plurality of ejection abnormality detecting means 10a to 10e are provided corresponding to the nozzles 110 of the plurality of ink jet heads 100a to 100e, and the
- the switching means 23a specified by the switching control means 19 Since only 23 to e perform a predetermined switching operation to detect a discharge abnormality of the ink jet head 100 and determine the cause thereof, the ink head 100 not performing the discharge drive operation is not used. For 0, this detection / determination process is not performed. Therefore, wasteful detection and determination processing can be avoided by the ink jet printer 1.
- FIG. 30 shows an example of the timing of the discharge abnormality detection of the plurality of ink jet heads 100 (discharge abnormality detection means). This is the case where the number of 100 is the same as the number of the ink jet heads 100, and the ink jet head 100 circulates to perform the ejection abnormality detection.
- the ink jet printer 1 shown in FIG. 30 in the configuration of the ink jet printer 1 shown in FIG. 29, one ejection abnormality detecting means 10 is used, and the drive / detection switching signal is scanned (detection The ink jet heads 100 for executing the determination process are specified one by one.) The switching selecting means 19a is added.
- the detection determining means repeats a selection operation of sequentially selecting an ink jet head from a plurality of ink jet heads 100a to 100e in a predetermined order.
- the ink jet head having the same timing is determined as an ink jet head for detecting and judging a discharge abnormality. It is configured to be. The details will be described below.
- the switching selection means 19a is connected to the switching control means 19 shown in FIG. 29, and based on a scanning signal (selection signal) input from the control unit 6, a plurality of inkjet heads.
- AND circuit corresponding to 100a to 100e This is a selector that scans (selects and switches) the input of the drive detection switching signal to ANDa to ANDe.
- the scanning (selection) order of the switching selection means 19a is the order of the print data inputted to the shift register 18a, that is, the order of evening, that is, the order of ejection of the plurality of ink jets 100. However, the order may be simply a plurality of ink jet heads 100a to 100e. In the configuration shown in FIG.
- the switching selecting means 19 a and the switching control means 19 are configured such that the ejection abnormality detecting means 10 includes a plurality of ink jet heads 100 a to 100 e.
- a detection determining means for determining which of the nozzles 110 the ejection failure is to be detected is configured.
- the scan order is the order of the print data input to the shift register 18 2a
- the print data is latched by the latch circuit 1.
- the signal is latched at 82 b and output to the driver 18 c when the latch signal is input.
- the inkjet head 100 In synchronization with the input of the print data to the shift register 18a or the input of the latch signal to the latch circuit 18b, it is possible to specify the inkjet head 100 corresponding to the print data.
- the scanning signal is input to the switching selection means 19a, and the drive / detection switching signal is output to the corresponding AND circuit.
- the output terminal of the switching selection means 19a outputs a low level when not selected.
- the corresponding AND circuit (switch control means 19) performs a logical AND operation on the print data input from the latch circuit 18b and the drive / detection switch signal input from the switch selection means 19a. As a result, a High level output signal is output to the corresponding switching means 23.
- the switching means 23 to which the high-level output signal has been input from the switching control means 19 connects the corresponding inkjet head 100 to the electrostatic actuator 120 by the drive waveform generation means 1. 8
- the mode is switched from 1 to the discharge abnormality detection means 10.
- the ejection failure detection means 100 detects the ejection failure of the inkjet head 100 to which the printing data has been input, and if there is a discharge failure, determines the cause and stores the result of the determination. Output to means 62. Then, the storage means 62 stores the judgment result thus input (obtained) in a predetermined storage area.
- the scanning order is a simple ink jet head 100a to 100e
- the The print data is latched by the latch circuit 18b, and is output to the driver 18c by the input of the latch signal.
- Scan (selection) signal is input to the switching selection means 19 a, and a drive / detection switching signal is output to the corresponding AND circuit of the switching control means 19. Is forced.
- the corresponding AND circuit switching control
- the output signal of the means 19 9) ′ becomes High level
- the switching means 23 switches the connection to the corresponding inkjet head 100 from the drive waveform generating means 18 1 to the ejection abnormality detecting means 10. Switch.
- the output signal of the AND circuit is at the low level, and the corresponding switching means 23 does not execute the predetermined switching operation. Therefore, based on the logical product of the selection result of the switching selecting means 19a and the result specified by the switching control means 19, the ejection abnormality detection / determination processing of the ink jet 100 is performed.
- the ejection failure detection unit 10 detects the ejection failure of the ink jet 100 to which the print data is input, and discharges the ink. If there is an abnormality, the cause is determined, and the determination result is output to the storage means 62. Then, the storage means 62 stores the judgment result thus input (obtained) in a predetermined storage area.
- the corresponding switching means 23 does not execute the switching operation as described above. It is not necessary to execute the ejection abnormality detection / determination processing by 10, but such processing may be executed. If the ejection failure detection / judgment processing is executed without performing the switching operation, the determination means 20 of the ejection failure detection means 10 will be turned off by the corresponding ink jet head 10 as shown in the flowchart of FIG. It is determined that the No. 0 nozzle 110 is a non-ejection nozzle (step S306), and the determination result is stored in a predetermined storage area of the storage means 62.
- the ink jet printer 1 shown in FIG. 30 has a plurality of ink jet heads 100a to 100e. Only one discharge abnormality detection means 10 is provided for each nozzle 110
- the print data corresponding to each of the inkjet heads 100a to 100e is input from the host computer 8 to the ejection selection means 182 via the control unit 6, and at the same time, a scanning (selection) signal is output.
- the switching means 23 corresponding to the inkjet head 100 that performs the ejection driving operation according to the print data performs the switching operation, and detects the ejection abnormality of the corresponding ink jet head 100.
- the discharge abnormality detection means 10 since the determination of the cause is performed, it is possible to reduce the burden on the CPU 61 of the control unit 6 without processing a large amount of detection results at one time.
- the discharge abnormality detection means 10 since the discharge abnormality detection means 10 circulates the nozzle state separately from the discharge operation, it is possible to grasp the discharge abnormality for each nozzle even during the drive printing, and the head unit 3 5 You can know the status of 0. Accordingly, for example, since the ejection abnormality is periodically detected, it is possible to reduce the number of steps for detecting the ejection abnormality for each nozzle while printing is stopped. As described above, it is possible to efficiently detect the discharge abnormality of the inkjet head 100 and determine the cause thereof.
- the ink jet printer 1 shown in FIG. 30 only needs to be provided with one ejection abnormality detecting means 10, and therefore, FIG. As compared with the inkjet printer 1 shown in FIG. 29, the circuit configuration of the inkjet printer 1 can be scaled down, and an increase in the manufacturing cost can be prevented.
- the ejection abnormality detection / judgment process (process in multiple nozzles) of the droplet ejection head according to the present invention is performed by a diaphragm when the electrostatic actuation unit 120 of each inkjet head 100 performs an ink droplet ejection operation.
- the residual vibration of 1 is detected, and based on the period of the residual vibration, whether or not ejection failure (dot missing, ink droplet non-ejection) has occurred for the corresponding inkjet head 100, dot missing (ink If a non-discharge occurs, it is determined what the cause is.
- the ink droplet (droplet) by the inkjet head 100 is used. If the ejection operation is performed, these detection and determination processes can be performed. However, the ink jet head 100 ejects ink droplets not only when the printing is actually performed on the recording paper P (printing) but also when the printing is performed. In some cases, a flushing operation (preliminary discharge or preliminary discharge) is being performed.
- the abnormality detection / determination process multiple nozzles of the droplet ejection head according to the present invention will be described for these two cases.
- the flushing (preliminary ejection) processing is performed when a cap (not shown in FIG. 1) is attached, or at a location (cleaning position) where ink droplets (droplets) are not applied to the recording paper P (media).
- This flushing process (flushing operation) is performed, for example, when periodically discharging the ink in the cavity 141, in order to maintain the ink viscosity in the nozzle 110 within a proper range. Alternatively, it is also performed as a recovery operation at the time of ink thickening. Further, the flushing process is also performed when the ink is initially filled in the cavities 141 after the ink cartridge 31 is mounted on the printing means 3.
- a wiping process cleaning of paper dust and dust, etc. adhering to the head surface of the head unit 35 is performed by cleaning the nozzle plate (nozzle surface) 150 with a wiper (not shown in FIG. 1).
- the flushing process is also performed so that a fixed amount of ink droplets are ejected from all the nozzles 110 of the head unit 35. Further, the flushing process can be performed in a timely manner in order to maintain the state of the meniscus of the nozzle 110 normally and to ensure good printing.
- FIGS. 31 to 33 a description will be given of the discharge abnormality detection and determination process in the flushing process. These flowcharts will be described with reference to the block diagrams of FIGS. 27 to 30 (the same applies to the printing operation).
- Figure 31 shows the ink jet shown in Figure 27.
- 9 is a flowchart illustrating timing of detecting a discharge abnormality during operation.
- the ejection abnormality detection / determination process shown in FIG. 31 is executed.
- the control unit 6 inputs the ejection data for one nozzle to the shift register 18 a of the ejection selection means 18 2 (step S 401), and the latch signal is input to the latch circuit 18 b. (Step S402) This ejection data is latched.
- the switching means 23 connects the electrostatic work 120 of the inkjet head 100, which is the object of the ejection data, to the drive waveform generating means 18 1 (step S40) 3).
- the ejection failure detection / measurement process shown in the flowchart of FIG. 24 is executed by the ejection failure detection means 10 on the ink jet head 100 that has performed the ink ejection operation (step S404).
- the control unit 6 controls all ink jet heads 100a of the ink jet printer 1 shown in FIG. 27 based on the ejection data output to the ejection selecting means 182. It is determined whether or not the ejection abnormality detection / determination processing has been completed for the nozzles 110 to 110e. When it is determined that these processes have not been completed for all the nozzles 110, the control unit 6 stores the shift register 18a in the nozzle 110 of the next inkjet head 100. The corresponding ejection data is input (step S406), and the process proceeds to step S402 to repeat the same processing.
- step S405 If it is determined in step S405 that the above-described ejection abnormality detection and determination processing has been completed for all nozzles 110, the control unit 6 sends a CLEAR signal to the latch circuit 18b. Input (step S407), the latched state of the latch circuit 18b is released, and the ejection failure detection / judgment process in the ink jet printer 1 shown in FIG. 27 ends.
- the detection circuit is composed of one ejection abnormality detection unit 10 and one switching unit 23.
- the discharge abnormality detection / determination process is repeated by the number of the ink jet 100, but the circuit constituting the discharge abnormality detection means 100 must be so large. This has the effect of
- FIG. 32 is a flowchart showing the timing of detecting an ejection failure during the flushing operation of the inkjet printer 1 shown in FIGS. 28 and 29.
- the ink jet printer 1 shown in FIG. 28 and the ink jet printer 1 shown in FIG. 29 have slightly different circuit configurations, the number of the ejection abnormality detecting means 10 and the switching means 23 is smaller than the number of the ink jet heads 100. Matches at corresponding (same) points. Therefore, the ejection abnormality detection / judgment process at the time of the flushing operation includes the same steps.
- the control unit 6 inputs ejection data for all nozzles to the shift register 182a of the ejection selection unit 182 (step S501). Then, a latch signal is input to the latch circuit 182b (step S502), and the ejection data is latched. At this time, the switching means 23a to 23e connect all the ink jet heads 100a to 100e and the drive waveform generating means 181 respectively (step S503).
- the ejection abnormality detecting means 10a to 100e corresponding to the respective ink jet heads 100a to 100e apply to all the inkjet heads 100 that have performed the ink ejection operation, as shown in FIG.
- the discharge abnormality detection / determination processing shown in the flowchart is executed in parallel (step S504).
- the determination results corresponding to all the inkjet heads 100a to 100e are stored in a predetermined storage area of the storage unit 62 in association with the inkjet head 100 to be processed (FIG. 24). Step S107).
- the control unit 6 inputs a CLEAR signal to the latch circuit 182b (step S505), and The latched state of b is released, and the discharge abnormality detection / determination process in the ink jet printer 1 shown in FIGS. 28 and 29 is completed.
- a plurality of (five in this embodiment) ejection abnormality detection means 10 corresponding to the jet heads 100 a to 100 e and a plurality of switching means 23 constitute a detection and determination circuit. Therefore, there is an effect that the discharge abnormality detection / determination processing can be executed in a short time for all the nozzles 110 at a time.
- FIG. 33 is a flowchart showing the timing of detecting a discharge abnormality during the flushing operation of the inkjet printer 1 shown in FIG.
- FIG. 33 is a flowchart showing the timing of detecting a discharge abnormality during the flushing operation of the inkjet printer 1 shown in FIG.
- a discharge abnormality detection / determination process during a flushing operation.
- the control unit 6 When the flushing process of the ink jet printer 1 is executed at a predetermined timing, first, the control unit 6 outputs a scanning signal to the switching selection means (selector) 19a, and the switching selection means 19
- the first switching means 23a and the ink jet head 100a are set (specified) by a and the switching control means 19 (step S601).
- the ejection data for all the nozzles is inputted to the shift register 18 2a of the ejection selecting means 18 2 (step S602), and the latch signal is inputted to the latch circuit 18 2b (step S60).
- the switching means 23a connects the electrostatic work 120 of the ink jet head 100a to the drive waveform generating means 181 (step S640).
- step S650 the ejection abnormality detection / determination process shown in the flowchart of FIG. 24 is executed for the inkjet head 100a that has performed the ink ejection operation.
- step S103 of FIG. 24 the drive Z detection switching signal, which is the output signal of the switching selection means 19a, and the ejection data output from the latch circuit 182b are ANDed with the AND circuit AND a
- the switching means 23a is connected to the electrostatic actuator 120 of the inkjet head 100a and the discharge abnormality detecting means 1 Connect to 0.
- step S606 the control unit 6 determines whether or not the discharge abnormality detection / determination process has been completed for all the nozzles. If it is determined that the ejection abnormality detection / determination process has not been completed for all the nozzles 110, the control unit 6 switches the scanning signal to the switching selection means (selector) 19a. The next switching means 23 b and the ink jet head 100 b are set (specified) by the switching selecting means 19 a and the switching control means 19 (step S 607). The process proceeds to S603 and the same processing is repeated. Hereinafter, this loop is repeated until the ejection abnormality detection / determination process is completed for all the ink jet heads 100.
- step S606 If it is determined in step S606 that the ejection abnormality detection / determination process has been completed for all the nozzles 110, the ejection is latched by the latch circuit 18b of the ejection selection means 182. In order to clear the ejection data, the control unit 6 inputs the CLEAR signal to the latch circuit 18b (step S609), releases the latch state of the latch circuit 18b, and 30. Detection of ejection abnormality in the ink jet printer 1 shown in FIG.
- a detection circuit is composed of a plurality of switching means 23 and one ejection abnormality detection means 10, and the switching selection means (selector) 19 a Only the switching means 23 corresponding to the inkjet head 100, which is specified by the scanning signal and drives the ejection in accordance with the ejection data, performs the switching operation, and the corresponding ink jet head 100, Since the discharge abnormality detection and the cause determination are performed, the discharge abnormality detection and the cause determination of the inkjet head 100 can be performed more efficiently.
- step S602 of this flowchart the ejection data corresponding to all the nozzles 110 is input to the shift register 182a, as shown in the flowchart of FIG.
- the discharge data to be input to the shift register 182a is input to the corresponding one of the inkjet heads 100, corresponding to the scan order of the inkjet head 100.
- the ejection abnormality detection / judgment processing may be performed for each nozzle 110.
- 27 is mainly suitable for the ejection abnormality detection / determination processing during the flushing operation, so the flow chart at the time of the printing operation and the description of the operation are omitted.
- ejection failure detection / determination processing may be performed during the printing operation.
- FIG. 34 is a flowchart showing the timing of ejection abnormality detection during the printing operation of the ink jet printer 1 shown in FIGS. 28 and 29.
- the process of this flowchart is executed (started) by a print (print) instruction from the host computer 8.
- a print (print) instruction from the host computer 8.
- a print (print) instruction from the host computer 8.
- a latch signal is input to the latch circuit 18 2 b.
- Step S702 the print data is latched.
- the switching means 23a to 23e connect all the inkjet heads 100a to 100e with the drive waveform generating means 181 (step S703).
- the ejection abnormality detecting means 10 corresponding to the inkjet head 100 that has performed the ink ejection operation executes the ejection abnormality detection / determination process shown in the flowchart of FIG. 24 (step S704).
- the respective determination results corresponding to the respective inkjet heads 100 are stored in a predetermined storage area of the storage means 62 in association with the target inkjet head 100 to be processed.
- the switching means 23 a to 23 e are based on the drive detection switching signal output from the control unit 6 and the ink jet head 100 a to Connect l 00 e to the discharge abnormality detection means 10 a to l 0 e (step S 103 in FIG. 24). Therefore, since the electrostatic actuator 120 is not driven in the ink jet head 100 where no printing data is present, the residual vibration detecting means 16 of the ejection abnormality detecting means 10 is vibrated. The residual vibration waveform of plate 1 2 1 is not detected. On the other hand, in the case of the ink jet printer 1 shown in FIG.
- the switching means 23 a to 23 e Is based on the output signal of the AND circuit to which the drive / detection switching signal output from the control section 6 and the print data output from the latch circuit 18b are input, to the ink jet where print data exists. Is connected to the discharge abnormality detecting means 10 (step S103 in FIG. 24).
- step S705 the control unit 6 determines whether the printing operation of the inkjet printer 1 has been completed. When it is determined that the printing operation has not been completed, the control unit 6 proceeds to step S701, inputs the next print data to the shift register 18a, Repeat the process. When it is determined that the printing operation has been completed, the controller 6 clears the CLEAR signal to clear the ejection data latched by the latch circuit 18 2 b of the ejection selection means 18 2. 182b (step S706) to release the latched state of the latch circuit 182b, and to detect and determine the discharge abnormality in the ink jet printer 1 shown in FIGS. 28 and 29. End the process.
- the ink jet printer 1 shown in FIGS. 28 and 29 includes a plurality of switching means 23 a to 23 e and a plurality of ejection abnormality detection means 10 a to 10 e.
- the inkjet printer 1 shown in FIG. 29 further includes a switching control means 19, that is, AND circuits ANDa to ANDe for performing a logical AND operation of the drive Z detection switching signal and the print data, and performs a printing operation. Since the switching operation by the switching means 23 is performed only for the ink jet 100 to be performed, the discharge abnormality detection / determination processing can be performed without performing useless detection.
- FIG. 35 is a flowchart showing the timing of detecting an ejection failure during the printing operation of the ink jet printer 1 shown in FIG.
- the processing of this flowchart is executed in the ink jet printer 1 shown in FIG.
- the switching selecting means 19a sets (specifies) the first switching means 23a and the ink jet head 100a in advance (step S). 8 0 1). '
- Step S 8 02 When print data is input from the host computer 8 via the control unit 6 to the shift register 18 2 a of the ejection selection means 18 2 (step S 8 02), a latch signal is input to the latch circuit 18 2 b (Step S803), and the print data is latched.
- the switching means 23a to 23e are, at this stage, all the ink jet heads 100a to 100e and the drive waveform generation means 181 (the driver of the ejection selection means 182). 18 2 c)) (step S804).
- step S805 the determination result of the discharge abnormality determination process executed in step S106 of FIG. 24 is associated with the inkjet head 100 (here, 1Q0a) to be processed, and The data is stored in a predetermined storage area of the storage means 62 (step S107 in FIG. 24).
- step S806 the control unit 6 determines whether or not the above-described discharge abnormality detection / determination processing has been completed for all nozzles 110 (all inkjet heads 100). If it is determined that the above processing has been completed for all the nozzles 110, the control unit 6 switches the switching means 23a corresponding to the first nozzle 110 based on the scanning signal. If it is determined that the above processing has not been completed for all nozzles 110 (step S 80.8), the switching means 2 3 b corresponding to the next nozzle 110 is set. Is set (step S807).
- step S809 the control unit 6 determines whether or not the predetermined printing operation instructed from the host computer 8 has been completed. If it is determined that the printing operation has not been completed, the next printing data is input to the shift register 18a (step S802), and the same processing is repeated. If it is determined that the printing operation has been completed, the ejection circuit latched by the latch circuit 18 2 b of the ejection selecting means 18 2 In order to clear the evening, the control unit 6 inputs the CLEAR signal to the latch circuit 18b (step S810), releases the latch state of the latch circuit 18b, and returns to FIG. The discharge abnormality detection / determination processing in the ink jet printer 1 shown in FIG.
- the droplet discharge device (inkjet printer 1) of the present invention includes a diaphragm 121, a plurality of electrostatic actuators 120 for displacing the diaphragm 122, and a liquid inside. Is filled, and the internal pressure is changed (increase / decrease) by the displacement of the diaphragm 12 1.
- the cavity 14 1 communicates with the cavity 14 1, and the pressure inside the cavity 14 1 changes (increase / decrease). ),
- a plurality of ink jet heads (droplet discharge heads) 100 each having a nozzle 110 for discharging liquid as liquid droplets, and these electrostatic actuation heads 120 are driven.
- ejection abnormality detection means 10 and the ejection operation of the droplets by the drive of the electrostatic actuator 120 based on a drive / detection switching signal, print data, or a scanning signal
- One or a plurality of switching means 23 for switching the electrostatic actuator 120 from the drive waveform generating means 18 1 to the discharge abnormality detecting means 10 0 is provided.
- the discharge abnormality of the nozzle 110 and the method of detecting and determining the discharge abnormality of the droplet discharge head and the droplet discharge head of the present invention can be performed in a short time.
- the circuit configuration of the detection circuit including the discharge abnormality detection means 10 can be scaled down, and an increase in the manufacturing cost of the droplet discharge device can be prevented.
- the discharge abnormality detecting unit 10 is switched to the discharge abnormality detecting unit 10 to perform the abnormality detection and the cause determination, so that the driving of the actuating unit is not affected. Thereby, the throughput of the droplet discharge device of the present invention is not reduced or deteriorated.
- the droplet discharge device of the present invention includes a plurality of switching means 23, a switching control means 19, and a plurality of abnormal discharge detections corresponding to one or the number of nozzles 110. And a corresponding electrostatic actuator based on the drive Z detection switching signal and the ejection data (print data) or the scanning signal, the drive / detection switching signal and the ejection data (print data).
- One night 120 is switched from the drive waveform generation means 18 1 or the ejection selection means 18 2 to the ejection abnormality detection means 10 to perform ejection abnormality detection and cause determination.
- the switching means corresponding to the electrostatic actuator 120 that has not received the discharge data (print data), that is, does not perform the discharge driving operation performs the switching operation. Since there is no need, useless detection / judgment processing can be avoided.
- the switching selection unit 19a the droplet discharge device only needs to include one discharge abnormality detection unit 10, so the circuit configuration of the droplet discharge device must be scaled down. In addition to this, it is possible to prevent an increase in the manufacturing cost of the droplet discharge device.
- the ink jet printer 1 shown in FIG. 27 to FIG. 30 for explaining the timing of ejection abnormality detection has five inkjet heads 10 attached to the head unit 35 for convenience of explanation. 0 (nozzle 110), and the configuration has been described.
- an inkjet head droplet discharge head
- the quantity of 100 is not limited to five, and it is possible to detect and determine a discharge abnormality for the number of nozzles 110 actually mounted.
- FIG. 36 is a diagram showing a schematic structure (partially omitted) as viewed from above the ink jet printer 1 shown in FIG.
- the ink jet printer 1 shown in FIG. 36 has a wiper 300 and a cap 31 for executing the ink droplet non-ejection (head abnormality) recovery process of the present invention. 0 is provided.
- the recovery processing performed by the recovery means 24 of the present invention includes the following operations for each ink jet head 1.
- a flushing process for preliminary discharging droplets from the nozzle No. 00, a wiping process using a wiper 300 described later (see FIG. 37), and a boping process using a tube pump 320 described later (pump suction process) ) Is included.
- the recovery means 24 comprises a tube pump 320 and a pulse motor for driving the same, a wiper 300 and a vertical drive mechanism for the wiper 300, and a vertical drive mechanism for the cap 310 (shown in FIG.
- the head driver 33 and the head unit 35 function, and in the wiping process, the carrier 41 and the like function as a part of the recovery means 24. Since the flushing process has been described above, the wiping process and the pumping process will be described below.
- the wiping process refers to a process of wiping foreign substances such as paper dust adhered to the nozzle plate 150 (nozzle surface) of the inkjet head 100 with the wiper 300.
- the bombing process is a process in which a tube pump 320 described later is driven to suck and discharge ink in the cavity 144 from the nozzle 110 of the inkjet head 100.
- the wiping process is an appropriate process as a recovery process in the state of paper dust adhesion, which is one of the causes of the above-described abnormal ejection of droplets of the inkjet head 100.
- the pump suction process removes air bubbles in the cavity 141 that cannot be removed by the flushing process described above, or the ink in the vicinity of the nozzle 110 is dried or the ink in the cavity 141 is deteriorated due to aging.
- This is an appropriate treatment as a recovery treatment to remove the thickened ink when the viscosity increases.
- the above-mentioned recovery process by the flushing process may be performed. In this case, since the amount of ink to be discharged is small, appropriate recovery processing can be performed without reducing throughput / running cost.
- a head unit 35 having a plurality of ink jet heads (droplet discharge heads) 100 is mounted on a carriage 32 and guided by two carriage guide shafts 4 2 2 to a carriage motor 4. By 1, it is connected to the timing belt 4 21 via the connecting portion 34 provided at the upper end in the figure and moves. Head mounted on carriage 32
- the unit 35 can be moved in the main scanning direction (in conjunction with the timing belt 421) via a timing belt 421 that is moved by driving the carriage motor 41.
- the carriage 41 plays a role of a pulley for continuously rotating the timing belt 421, and a pulley 44 is similarly provided on the other end side.
- the cap 310 is used for cabling the nozzle plate 150 of the inkjet head 100 (see FIG. 5).
- a hole is formed in the bottom surface of the cap 310, and a flexible tube 321, which is a component of the tube pump 320, is connected to the cap 310 as described later.
- the tube pump 320 will be described later with reference to FIG.
- the recording paper P is driven in the sub-scanning direction, that is, in FIG. 36, while driving a predetermined inkjet head (droplet discharge head) 100 of electrostatic actuation 120.
- the printing means 3 moves in the main scanning direction, that is, left and right in FIG. 36, so that the ink jet head (droplet discharge device) 1 prints the print data (input from the host computer 8). Prints (records) a predetermined image on recording paper P based on the print data.
- FIG. 37 is a diagram showing a positional relationship between the wiper 300 and the head unit 35 shown in FIG.
- the head unit 35 and the wiper 300 are shown as a part of a side view of the ink jet printer 1 shown in FIG. 36 when viewed from below in the figure.
- the wiper 300 can be moved up and down so that it can contact the nozzle surface of the head unit 35, that is, the nozzle plate 150 of the inkjet head 100. Be placed.
- the wiping process which is the recovery process using the wiper 300
- the wiper 300 is driven by a drive unit (not shown) such that the tip of the wiper 300 is located above the nozzle surface (nozzle plate 150). 0 0 is moved upward.
- the carriage motor 41 is driven to move the head unit 35 leftward (in the direction of the arrow) in the drawing, the wiping member 301 comes in contact with the nozzle plate 150 (nozzle surface). Especially You.
- the tip of the wiping member 301 that comes into contact with the nozzle plate 150 is The surface of the nozzle plate 150 (nozzle surface) is cleaned (wiped) by the bending and the tip. This makes it possible to remove foreign matter such as paper dust attached to the nozzle plate 150 (nozzle surface) (for example, paper dust, dust floating in the air, and pieces of rubber).
- the head unit 35 is reciprocated above the wiper 300 to perform the wiping process a plurality of times. You can also.
- FIG. 38 is a diagram showing the relationship between the inkjet head 100, the cap 310 and the pump 320 during the pump suction process.
- the tube 3 21 forms an ink discharge path in the pumping process (pump suction process), and one end thereof is connected to the bottom of the cap 310 as described above, and the other end is a tube pump. It is connected to the ink discharge cartridge 340 via 340.
- An ink absorber 330 is arranged on the inner bottom surface of the cap 310.
- the ink absorber 330 absorbs the ink discharged from the nozzle 110 of the ink jet head 100 during the pump suction process and the flushing process, and temporarily stores the ink.
- the ink absorber 330 can prevent the ejected droplets from splashing back and fouling the nozzle plate 150 during the flushing operation into the cap 310.
- FIG. 39 is a schematic diagram showing the configuration of the tube pump 320 shown in FIG.
- the tube pump 320 is a rotary pump, and includes a rotating body 322 and four rollers 3 arranged on the circumference of the rotating body 322. 23 and a guide member 350.
- the roller 3 23 is supported by a rotating body 3 22, and a flexible tube 3 21 placed in an arc along the guide 3 51 of the guide member 350 is applied. To press.
- the rotating body 322 is centered on the shaft 32a as shown in FIG.
- one or two rollers 3 2 3 in contact with the tube 3 2 1 rotate in the Y direction, and the arcuate guide 35 of the guide member 350 is rotated.
- the tube 3 2 1 placed in 1 is pressurized sequentially. As a result, the tube 3 2 1 is deformed, and the negative pressure generated in the tube 3 2 1 causes the ink (liquid material) in the cavity 14 1 of each ink jet head 4 0 to cap 3 10.
- Unnecessary ink that was sucked through, mixed with air bubbles, or thickened by drying was discharged to the ink absorber 330 through the nozzle 110, and was absorbed by the ink absorber 330.
- the discharged ink is discharged to the discharged ink cartridge 3400 (see FIG. 38) via the tube pump 320.
- the tube pump 320 is driven by a motor such as a pulse motor (not shown).
- the pulse mode is controlled by the control unit 6.
- Drive information for the rotation control of the tube pump 320 for example, a look-up table in which the rotation speed and the number of rotations are described, a control program in which the sequence control is described, and the like, are stored in the PROM 6.4 of the control unit 6, etc.
- the CPU 61 of the control unit 6 controls the tube pump 320 based on the drive information.
- FIG. 40 is a flowchart showing an ejection failure recovery process in the inkjet printer 1 (droplet ejection device) of the present invention.
- the inkjet head 100 of the ejection failure is detected, and if the cause is determined, a printing operation (printing operation) is performed.
- a printing operation printing operation
- the head unit 35 is not in the predetermined standby area at a predetermined timing (for example, depending on the position where the nozzle plate 150 of the head unit 35 is covered with the cap 310 in FIG. 36 or the wiper 300). (The position where the wiping process can be performed), and the ejection failure recovery process of the present invention is executed.
- the control unit 6 determines the determination result corresponding to each nozzle 110 stored in the EEPROM 62 of the control unit 6 in step S107 in FIG. 24 (where the determination result is Each inkjet head 1 0 For 0. Therefore, in the following, the ejection failure nozzle 110 also means the inkjet head 100 in which the ejection failure has occurred. ) Is read (step S910). In step S902, the control unit 6 determines whether or not the read determination result includes the nozzle 110 having an ejection failure. Then, when it is determined that there is no nozzle 110 with a discharge abnormality, that is, when the liquid droplets are normally discharged from all the nozzles 110, the discharge abnormality recovery processing is terminated as it is.
- step S903 the control unit 6 determines that the nozzle 110 that has been determined to have the discharge abnormality It is determined whether or not it is adhesion.
- the process proceeds to step S905, and when it is determined that paper dust is attached, Then, the wiping process for the nozzle plate 150 by the wiper 300 described above is executed (step S904).
- step S905 subsequently, the control unit 6 determines whether or not the nozzle 110 that has been determined to have the above-described ejection abnormality is a bubble. Then, when it is determined that air bubbles are mixed, the control unit 6 executes a pump suction process by the tube pump 320 for all the nozzles 110 (step S906), and The discharge abnormality recovery process ends. On the other hand, if it is determined that there is no air bubble, the control unit 6 sets the pump by the tube pump 320 on the basis of the length of the cycle of the residual vibration of the diaphragm 121 measured by the measuring unit 17. The flushing process is performed on only the nozzle 110 or all the nozzles 110 determined to be the suction process or the discharge abnormality (step S ⁇ b> 907), and the discharge abnormality recovery process ends.
- a discharge abnormality detecting means 10 for detecting a discharge abnormality and its cause with respect to a plurality of ink jet heads 100 of the head unit 35, and a nozzle 110 of the droplet discharge head 100.
- the apparatus is provided with recovery means (for example, a tube pump 320 in the pump suction processing, a wiper 300 in the wiping processing, etc.) for executing the recovery processing in accordance with the cause of the discharge abnormality.
- the droplet discharge device (inkjet printer 1) of the present invention includes a diaphragm 121 displaced by a drive of an electrostatic actuator 120 on a droplet discharge head (inkjet head 100).
- the ejection abnormality detecting means 10 is configured to detect the ejection abnormality of the droplet based on the vibration pattern (for example, the period of the residual vibration) of the residual vibration of the diaphragm 121 during the droplet ejection operation. I have.
- the present invention does not require other components (for example, an optical dot missing detector, etc.) as compared with the conventional droplet discharge device capable of detecting a discharge abnormality, so that the size of the droplet discharge head is reduced.
- the abnormal discharge of the droplet is detected using the residual vibration of the diaphragm after the droplet discharge operation, so that the abnormal discharge of the droplet is detected even during the printing operation. can do.
- the pump suction recovery process which is one of the recovery processes performed by the recovery means 24, is an effective process for the case where the viscosity has increased due to drying or the like and the case where bubbles are mixed. Since the same recovery process can be applied to the cause, if an air-jet and a thickened ink jet 100 that requires a pump suction process in the head unit 35 is detected, the ink jet head shown in FIG. Step of the mouth of the nozzle of 0 The processing was not determined individually as in S905 to S907, but the ink head with air bubbles was mixed with the ink head with drying and thickening.
- the pump suction process may be performed on the head 100 at a time.
- the pump suction process may be executed without determining whether air bubbles are mixed or the viscosity is increased. Further, the pump suction processing may be performed on a predetermined area including the ink jet head 100 where the discharge abnormality has occurred, and the head unit including the ink jet head 100 where the discharge abnormality has occurred. It may be performed for all kinds or types of ink.
- FIG. 41 to FIG. 44 are cross-sectional views each schematically showing another configuration example of the inkjet head 100.
- description will be made based on these drawings, but the description will be focused on points different from the above-described embodiment, and the description of the same matters will be omitted.
- the vibration plate 212 vibrates by driving the piezoelectric element 200, and the ink (liquid) in the cavity 208 is ejected from the nozzle 203. Things.
- the stainless steel nozzle plate 202 with the nozzle (hole) 203 formed thereon is joined with a stainless steel metal plate 204 via an adhesive film 205.
- a metal plate 20 made of the same stainless steel as above is joined via an adhesive film 205.
- a communication port forming plate 206 and a cavity plate 207 are sequentially joined thereon.
- the nozzle plate 202, the metal plate 204, the adhesive film 205, the communication port forming plate 206 and the cavity plate 200 each have a predetermined shape (shape such that a concave portion is formed). By molding and overlapping these, a cavity 208 and a reservoir 209 are formed.
- the cavity 208 and the reservoir 209 communicate with each other via an ink supply port 210.
- the reservoir 209 communicates with the ink intake port 211.
- a vibrating plate 212 is provided at an opening on the upper surface of the cavity plate 207, and a piezoelectric element (piezoelectric element) 200 is provided on the vibrating plate 212 via a lower electrode 21. Joined Have been.
- An upper electrode 214 is joined to the piezoelectric element 200 on the side opposite to the lower electrode 211.
- the head driver 2 15 includes a drive circuit for generating a drive voltage waveform, and applies (supplies) the drive voltage waveform between the upper electrode 2 14 and the lower electrode 2 13 so that the piezoelectric element 200 Vibrates, and the diaphragm 2 1 2 bonded thereto vibrates. Due to the vibration of the vibration plate 212, the volume of the cavity 208 (pressure in the cavity) changes, and the ink (liquid) filled in the cavity 208 is ejected from the nozzle 203 as a liquid droplet.
- the amount of liquid reduced in the cavity 208 due to the ejection of the liquid droplets is supplied from the reservoir 209 by supplying ink.
- ink is supplied to the reservoir 209 from the ink intake port 211.
- the ink jet head 100B shown in FIG. 42 discharges the ink (liquid) in the cavity 22 from the nozzle by driving the piezoelectric element 200 in the same manner as described above.
- This ink jet head 100B has a pair of opposed substrates 220, and a plurality of piezoelectric elements 200 are intermittently arranged at a predetermined interval between the two substrates 220.
- a cavity 2 21 is formed between adjacent piezoelectric elements 200.
- a plate (not shown) is installed at the front in FIG. 42 of the cavity 2 21, and a nozzle plate 222 is installed at the rear, and the nozzle plate 222 is located at a position corresponding to each cavity 222 of the nozzle plate 222.
- a nozzle (hole) 222 is formed.
- a pair of electrodes 224 is provided on one surface and the other surface of each piezoelectric element 200, respectively. That is, four electrodes 224 are connected to one piezoelectric element 200.
- the piezoelectric element 200 is deformed in shear mode and vibrates (indicated by an arrow in FIG. 42). The vibration changes the volume of the cavity 222 (pressure inside the cavity), and the ink (liquid) filled in the cavity 222 is ejected from the nozzle 222 as a liquid droplet. That is, in the ink jet head 100 B, the piezoelectric element 200 itself functions as a diaphragm.
- the ink-jet head 100C shown in FIG. 43 discharges ink (liquid) in the cavity 23 from the nozzle 231 by driving the piezoelectric element 200.
- the ink jet head 100C includes a nozzle plate 230 on which the nozzles 231 are formed, a spacer 232, and a piezoelectric element 200.
- the piezoelectric element 200 is installed at a predetermined distance from the nozzle plate 230 through a spacer 23, and the nozzle plate 230, the piezoelectric element 200, and the spacer 23 A cavity 2 3 3 is formed in the space surrounded by 2.
- a plurality of electrodes are joined to the upper surface of the piezoelectric element 200 in FIG. That is, a first electrode 234 is joined to a substantially central portion of the piezoelectric element 200, and a second electrode 235 is joined to both sides thereof.
- the piezoelectric element 200 deforms in a shear mode and vibrates (indicated by an arrow in FIG. 43). Due to this vibration, the volume of the cavity 23 3 (pressure in the cavity) changes, and the ink (liquid) filled in the cavity 2 33 is ejected as droplets from the nozzle 2 31. That is, in the inkjet head 100 C, the piezoelectric element 200 itself functions as a diaphragm.
- the ink jet head 100D shown in FIG. 44 also discharges the ink (liquid) in the cavity 245 from the nozzle 241 by driving the piezoelectric element 200 in the same manner as described above.
- This ink jet head 100D is composed of a nozzle plate 240 on which the nozzles 241 are formed, a cavity plate 242, a vibration plate 243, and a plurality of piezoelectric elements 200. And a multi-layer piezoelectric element 201.
- the cavity plate 242 is formed in a predetermined shape (shape such that a concave portion is formed), whereby the cavity 245 and the reservoir 246 are formed.
- the cavities 245 and the reservoirs 246 communicate with each other via the ink supply ports 247.
- the reservoir 246 communicates with the ink cartridge 31 via the ink supply tube 311.
- the middle and lower ends of the multilayer piezoelectric element 201 shown in FIG. 44 are connected to the diaphragm 243 via the intermediate layer 244.
- the multilayer piezoelectric element 201 has a plurality of external electrodes 248 and internal electrodes 244. 9 are joined. That is, an external electrode 248 is bonded to the outer surface of the multilayer piezoelectric element 201, and is provided between the piezoelectric elements 200 constituting the multilayer piezoelectric element 201 (or inside each piezoelectric element).
- the internal electrode 249 is installed. In this case, the external electrodes 248 and a part of the internal electrodes 249 are alternately arranged so as to overlap in the thickness direction of the piezoelectric element 200.
- the multilayer piezoelectric element 201 is deformed as shown by the arrow in FIG. Vibrating (expanding and contracting in the vertical direction in Fig. 44), and this vibration causes the vibration plate 243 to vibrate. Due to the vibration of the vibration plate 243, the volume of the cavity 245 (pressure in the cavity) changes, and the ink (liquid) filled in the cavity 245 is ejected from the nozzle 241 as droplets.
- the liquid amount reduced in the cavity 245 due to the ejection of the liquid droplets is supplied from the reservoir 246 to be supplied with ink.
- Ink is supplied to the reservoir 246 from the ink cartridge 31 via the ink supply tube 311.
- the ink jet heads 100 A to 100 D having the above-described piezoelectric elements also function as diaphragms or diaphragms in the same manner as the above-described capacitive inkjet head 100. Based on the residual vibration of the piezoelectric element, it is possible to detect an abnormality in droplet ejection or to specify the cause of the abnormality.
- a diaphragm a diaphragm for detecting residual vibration
- a sensor is provided at a position facing the cavity to detect residual vibration of the diaphragm. It can also be configured.
- FIG. 45 is a block diagram showing a main part of a third embodiment of the droplet discharge device of the present invention
- FIG. 46 is a block diagram of one block of the droplet discharge device shown in FIG.
- the third embodiment will be described focusing on the differences from the first embodiment. The description of the same items is omitted.
- n (where n is a natural number) ink jet heads (droplet discharge heads) 100 are defined as one block, and m ( ⁇ , m is a natural number)
- n (where n is a natural number) ink jet heads (droplet discharge heads) 100 are defined as one block, and m ( ⁇ , m is a natural number)
- a plurality of the blocks (head blocks) 50 are provided, and the same number (m) of the discharge abnormality detection means 10 as the blocks 50 are provided.
- Each of the discharge abnormality detection means 10 is assigned to a predetermined block 10. .
- a flushing means is operated (by performing a flushing process), and the non-recording area (from the nozzle 110 of each ink jet head 100)
- the ink droplets are ejected n times to a predetermined area where the ink droplets (droplets) may land).
- each ejection abnormality detecting means 10 sends n ink jets to the assigned block 50 in each of the assigned blocks 50. Detection and determination of discharge abnormality are sequentially performed on the head 100.
- the printing means 3 includes four blocks (head blocks) 50 for four color inks of yellow (Y), magenta (M), cyan (C), and black (K). a, 50b, 50c, and 50d. Each block 50a, 50b, 50c, 50d has an ink jet 100 for yellow (Y), magenta (M), cyan (C), and black (K) inks, respectively. (Nozzles 110) are arranged.
- yellow is described as “Y”, magenta as “ ⁇ ”, cyan as “C”, and black as “K”.
- Discharge abnormality detecting means 10a, 1.0b, 10c, and 10d are assigned to the blocks 50a, 50b, 50c, and 50d, respectively. Further, one judging means 20 is provided separately from the ejection abnormality detecting means 10, 10b, 10c, and 10d.
- the number of the determination means 20 may be plural, for example, as many as the number of the discharge abnormality detection means, and the determination means 20 may be included in the discharge abnormality detection means.
- FIG. 46 shows a block 50a of Y, and as shown in FIG.
- the ink jet head 100 is connected to a discharge abnormality detecting means 10a and a drive waveform generating means 18 1 via an opening / closing switch 501 and a switching means 23, respectively.
- Each open / close switch 501 and switching means 23 are controlled by the control unit 6.
- print data (print data) input from the host computer 8 passes from the shift register 18 c to the latch circuit 18 b, and is output from the plurality of inkjet heads 100.
- An ink jet 100 for ejecting ink droplets is selected.
- the drive waveform from the drive waveform generating means 181 of the drive circuit 18 is sent to a predetermined inkjet head 100 via the driver 18c.
- ink droplets are ejected from the nozzles 110 of the predetermined ink jet head 100, and the ink droplets land on the recording paper P to perform recording.
- some nozzles 110 eject ink droplets frequently, depending on the images or characters to be recorded, but some nozzles 110 eject little ink droplets.
- the printing means 3 when the printing means 3 is at the cleaning position, which is a non-recording area, it periodically performs a flushing process to prevent the nozzle 110 from drying, and to maintain a good state. Have maintained.
- the number of ejections of the ink droplets in the flushing process is set several times depending on, for example, the ambient temperature / the time interval of the flushing process, and is about several ten to several thousand times.
- detection and determination of an ejection abnormality are performed at the time of the flushing process. As a result, no special time is required for the detection and determination of the discharge abnormality, the efficiency is high, and the ink consumption can be minimized.
- the switching unit 23 is switched to the drive waveform generation unit 181 side (the switching unit 23 is connected so that the drive waveform generation unit 181 and the ink jet head 100 are connected).
- the switching means 23 is switched to the ejection abnormality detection means 10a side (the switching means 23 is switched so that the ejection abnormality detection means 10a and the ink jet head 100 are connected), and the opening / closing switch 501 ( Except for 1), turn off the open / close switches 501 (2) to 501 (n).
- the inkjet head 100 (1) is connected to the ejection abnormality detection means 10a, and the ejection abnormality is detected and determined for the inkjet head 100 (1) as described above.
- the switching means 23 is again switched to the drive waveform generation means 181 side, all of the open / close switches 501 (1) to 501 (n) are turned on, and ink droplets are ejected from the nozzles 110 of all the inkjet heads 100. (The second ink droplet ejection is performed.)
- the switching means 23 is switched to the discharge abnormality detecting means 10a, and the remaining open / close switches 501 are turned off except for the open / close switch 501 (2).
- the inkjet head 100 (2) is connected to the ejection abnormality detection means 10a, and the ejection abnormality is detected and determined for the inkjet head 100 (2) as described above.
- the detection and determination of the discharge abnormality are sequentially performed for the inkjet heads 100 (3) to 100 (n) one by one.
- the discharge abnormality can be detected and determined once each.
- each color of Y, M, C, K may be divided into a plurality of blocks.
- timing timing at which the detection and determination of a discharge abnormality are performed by discharging the ink droplets ⁇ times (performed together with the flushing process).
- Examples of the timing for performing the detection and determination of the ejection abnormality performed together with the flushing process include the following (1) to (4). From these, only one may be selected. You can select any two or more (you can combine any two or more).
- the state of the nozzle 110 of each ink jet head 100 can be favorably maintained, and the discharge abnormality of each nozzle 110 can be detected and determined periodically.
- the state of the nozzles 110 of each ink jet head 100 can be maintained in a good state, and each time the ink jet head 100 (printing means 3) reciprocates, the nozzles 110 Discharge abnormality can be detected and determined.
- the nozzles 110 of each ink jet head 100 can be reliably brought into a good state, and the nozzles 110 Discharge abnormality can be detected and determined.
- the nozzles 110 of each ink jet head 100 can be reliably brought into a good state, and the nozzles 110 Discharge abnormality can be detected and determined.
- the detection and determination of the discharge abnormality are performed during the flushing process, so that no special time is required for the detection and determination of the discharge abnormality, and the efficiency is improved.
- the ink consumption can be minimized, and the ejection abnormality of the nozzle 110 of each inkjet head 100 can be detected and determined.
- the number of ink droplet ejections (n times) matches the number of inkjet heads 100 in one block (n), and the number of ejection failure detection means 10 is equal to the number of blocks (n). m), so that it is possible to reliably detect and judge the discharge abnormality one by one, by discharging the ink droplets n times, and to determine the number of the discharge abnormality detection means 10 It is possible to reduce the circuit configuration, scale down the circuit configuration, and prevent an increase in manufacturing cost.
- FIG. 47 is a perspective view showing the configuration of the head unit 100H
- FIG. 48 is a schematic diagram corresponding to one color ink (one cavity) of the head unit 100H shown in FIG. It is sectional drawing.
- the description will be made based on these drawings, but the description will be focused on the points different from the first embodiment described above, and the description of the same matters will be omitted.
- the head unit 100 H shown in these figures is based on a so-called film boiling ink jet system (thermal jet system), and includes a support plate 410, a substrate 420, an outer wall 430 and a partition wall 331. And the top plate 44 are joined in this order from the lower side in FIGS. 47 and 48.
- film boiling ink jet system thermal jet system
- the substrate 420 and the top plate 400 are arranged at a predetermined interval via the outer wall 430 and a plurality of (six in the illustrated example) partition walls 431 arranged in parallel at equal intervals. Have been. A plurality of partitions defined by partition walls 431 are provided between the substrate 4200 and the top plate 4440.
- the cavities (pressure chambers: ink chambers) 432 (5 in the illustrated example) are formed. Each of the cavities 4 3 2 is in the shape of a strip (cuboid).
- each cavity 4 32 in FIG. 48 is covered by a nozzle plate (front plate) 4 33.
- the nozzle plate 4334 has a nozzle (hole) 4334 force S communicating with each cavity 4332, from which ink (liquid material) is discharged.
- the nozzles 4334 are arranged linearly, that is, in a row with respect to the nozzle plate 433, but it goes without saying that the arrangement pattern of the nozzles 110 is not limited to this.
- the pitch of the nozzles 434 arranged in a row can be appropriately set according to the printing resolution (d p i) and the like.
- the nozzle plate 4 33 may not be provided, and the upper end (left end in FIG. 48) of each cavity 4 32 in FIG. 47 may be opened, and the configuration may be such that this opened opening serves as a nozzle. . ⁇
- an ink intake port 4 41 is formed in the top plate 4 40, and the ink intake port is connected to the ink cartridge 31 via an ink supply tube 3 1 1.
- a damper chamber (equipped with a rubber damper, whose capacity changes due to its deformation) is provided between the ink intake port 44 1 and the ink cartridge 31. You can also. This allows the damper chamber to absorb fluctuations in ink and changes in ink pressure when the carriage 32 reciprocates, so that a predetermined amount of ink can be stably supplied to the head unit 100H.
- the support plate 4 10, outer wall 4 3 0, partition 4 3 1, top plate 4 4 0, and nozzle plate 4 3 3 are each made of various metal materials such as stainless steel, various resin materials, various ceramics, etc. Have been.
- the substrate 420 is made of, for example, silicon or the like.
- Heating elements 450 are installed (buried) at the locations corresponding to the cavities 432 of the substrate 420, respectively. Each of the heating elements 450 is separately energized by a head driver (electrical conduction means) 452 to generate heat. Head dora In response to a print signal (print data) input from the control section 6, the driver 452 outputs, for example, a pulse-like signal as a pulsating signal of the heating element 450.
- the surface of the heating element 450 on the side of the cavity 4332 is covered with a protective film (anti-cavitation film) 451.
- the protective film 451 is provided to prevent the heating element 450 from directly contacting the ink in the cavity 432.
- a concave portion 460 is formed in the vicinity of each heating element 450 on the substrate 420 and at a location corresponding to each cavity 4322.
- the concave portion 460 can be formed by, for example, etching, punching, or the like.
- the diaphragm 461 is installed so as to shield the cavity 432 side of the concave portion 4600.
- the diaphragm 461 elastically deforms (elastically displaces) in the vertical direction in FIG. 48 following changes in the pressure (fluid pressure) in the cavity 4 32.
- the constituent material and thickness of diaphragm 461 are not particularly limited, and are appropriately set.
- the other side of the concave portion 460 is covered with a support plate 410, and a portion of the support plate 410 corresponding to each diaphragm 461 on the upper surface in FIG.
- the segment electrodes 4 6 2 are installed.
- Diaphragm 461 and segment electrode 462 are arranged substantially in parallel with a predetermined gap distance.
- the gap distance (gap length g) between diaphragm 461 and segment electrode 462 is not particularly limited, and is set as appropriate.
- a parallel plate capacitor can be formed. Then, as described above, when the diaphragm 4 61 follows the pressure in the cavity 4 32 and elastically deforms in the vertical direction in FIG. 48, the diaphragm 4 61 and the segment electrode 4 62 And the gap distance changes, and the capacitance C of the parallel plate capacitor changes.
- This change in the capacitance C appears as a frequency change when oscillated by the CR oscillation circuit and is converted into frequency information. As described above, by detecting this, the residual vibration ( Damping vibration). Outside the cavity 432 of the substrate 420, a common electrode 470 is formed. An external segment electrode 471 is formed outside the cavity 432 of the support plate 4110.
- the constituent materials of the segment electrode 462, the common electrode 470, and the external segment electrode 471 include, for example, stainless steel, aluminum, gold, copper, and alloys containing these.
- the segment electrode 462, the common electrode 470, and the external segment electrode 471 can be formed by, for example, a method such as bonding of metal foil, plating, vapor deposition, and sputtering.
- Each diaphragm 4 6 1 and the common electrode 4 7 0 are electrically connected by a conductor 4 7 5, and each segment electrode 4 6 2 and each external segment electrode 4 7 1 are electrically connected by a conductor 4 7 6 It is connected to the.
- the conductors 475 and 476 are, respectively, (1) a conductive wire such as a metal wire, and (2) a conductive material such as gold, copper or the like on the surface of the substrate 420 or the support plate 410. And (3) those in which a conductive portion such as the substrate 420 is subjected to ion doping or the like so as to have conductivity, and the like.
- the plurality of head units 100H as described above can be arranged so as to be overlapped (in other stages) in the vertical direction in FIG.
- FIG. 49 shows an example of the arrangement of the nozzles 4 3 4 when four colors of ink (ink force cartridge 3 1) are applied.
- a plurality of head units 100 H are moved in the main scanning direction, for example.
- the arrangement pattern of the nozzles 4 3 4 on the nozzle plate 4 3 3 is not particularly limited, but as shown in FIG. 49, the nozzles 4 3 4 are arranged such that the nozzles 4 3 4 are shifted by half a pitch in adjacent nozzle rows. be able to.
- a drive signal (pulse signal) is output from the head driver 33 and is passed through the heating element 450
- the heating element 450 instantaneously generates heat to a temperature of 300 ° C. or more.
- air bubbles due to film boiling on the protective film 45 1 (in the cavity causing non-discharge described later) 480 is generated, and the bubble 480 expands instantaneously.
- the liquid pressure of the ink (liquid material) filled in the cavity 432 increases, and a part of the ink is ejected from the nozzle 434 as droplets.
- the bubble 480 Immediately after the ink droplet is ejected, the bubble 480 rapidly contracts and returns to its original state. At this time, the diaphragm 461 is elastically deformed by the pressure change in the capty 432, and damping vibration (residual vibration) is generated until the next drive signal is input and the ink droplet is ejected again.
- the capacitance between the vibration plate 461 and the segment electrode 462 opposite thereto changes accordingly.
- This change in the capacitance appears as a change in the voltage difference between the common electrode 470 and the external segment electrode 471.
- the non-ejection of the ink droplet or the cause thereof can be detected and specified. Can be. That is, when the ink droplets are normally ejected from the nozzles 434, the voltage difference between the common electrode 470 and the external segment electrode 471 (change in capacitance) is compared with the pattern (pattern). In this way, it is possible to determine whether or not the ink droplet has been ejected normally.
- the ink droplet has been ejected.
- the cause of the ejection can be determined.
- the amount of liquid reduced in the cavity 4 32 by the ejection of the ink droplets is replenished by supplying new ink into the cavity 4 32 from the ink intake port 4 41. This ink is supplied from the ink cartridge 31 through the ink supply tube 311.
- the droplet ejection apparatus and the droplet ejection head ejection abnormality detection / determination method of the present invention include: a plurality of droplet ejection heads each including a cavity, a diaphragm, an actuator, and a nozzle; A drive circuit for driving the actuator, ejection selection means for selecting a nozzle of a droplet ejection head based on print data, etc., and one or more for detecting abnormal ejection of droplets from residual vibration of the diaphragm And one or a plurality of switching means for switching between a drive circuit and a discharge abnormality detection means for detecting a residual vibration of the diaphragm after a droplet discharge operation in a flushing operation or a printing operation. , Based on it, discharge Abnormality is detected and determined.
- the multi-nozzle droplet ejection head can be provided by the droplet ejection device and the droplet ejection head detection / determination method of the present invention without providing another detection device in the droplet ejection head. It is possible to detect and determine the ejection abnormality for each of the nozzles, so that it is not necessary to increase the size of the droplet ejection head, and to prevent an increase in the manufacturing cost of the droplet ejection device capable of detecting the ejection abnormality be able to.
- the droplet ejection apparatus and the ejection abnormality detection / determination method of the droplet ejection head according to the present invention have been described based on the illustrated embodiments.
- the present invention is not limited thereto.
- Each component constituting the droplet discharge head or the droplet discharge device can be replaced with an arbitrary component having the same function. Further, any other components may be added to the droplet discharge head or the droplet discharge device of the present invention.
- the liquid to be discharged (droplets) discharged from the droplet discharge head (in the above-described embodiment, the ink jet head 100) of the droplet discharge device of the present invention is not particularly limited.
- an ink containing a filter material of a color filter, a light emitting material for forming an EL light emitting layer in an organic EL (Electro Luminescence) device, a fluorescent material for forming a phosphor on an electrode in an electron emitting device, Fluorescent materials for forming phosphors in PDP (Plasma Display Panel) devices, electrophoretic materials for forming electrophores in electrophoretic displays, puncture materials for forming banks on the surface of substrate W, various types Coating material, liquid electrode material for forming electrodes, particle material for forming a spacer for forming a minute cell gap between two substrates, liquid metal material for forming metal wiring, micro Lens materials for forming lenses, resist materials, and light diffusing materials for forming light diffusers.
- the droplet receiver from which droplets are to be discharged is not limited to paper such as recording paper, but may be other media such as films, woven fabrics and non-woven fabrics, glass substrates, silicon substrates and the like. Work such as various substrates may be used. Industrial applicability
- the present invention it is possible to detect and determine the discharge abnormality of each nozzle of a droplet discharge head having a plurality of nozzles, and to scale the circuit configuration of such a droplet discharge device. It is possible to reduce the production cost and prevent the production cost from increasing.
Landscapes
- Ink Jet (AREA)
- Coating Apparatus (AREA)
- Particle Formation And Scattering Control In Inkjet Printers (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP04715497A EP1600294A4 (en) | 2003-02-28 | 2004-02-27 | LIQUID DROP EJECTOR AND METHOD OF DETECTING / ESTIMATING AN ABNORMAL EJECTION OF A LIQUID DROP EJECTION HEAD |
JP2005502958A JP3794431B2 (ja) | 2003-02-28 | 2004-02-27 | 液滴吐出装置及び液滴吐出ヘッドの吐出異常検出・判定方法 |
Applications Claiming Priority (6)
Application Number | Priority Date | Filing Date | Title |
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JP2003055021 | 2003-02-28 | ||
JP2003055020 | 2003-02-28 | ||
JP2003-055020 | 2003-02-28 | ||
JP2003-055021 | 2003-02-28 | ||
JP2003092934 | 2003-03-28 | ||
JP2003-092934 | 2003-03-28 |
Publications (1)
Publication Number | Publication Date |
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WO2004076180A1 true WO2004076180A1 (ja) | 2004-09-10 |
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PCT/JP2004/002390 WO2004076180A1 (ja) | 2003-02-28 | 2004-02-27 | 液滴吐出装置及び液滴吐出ヘッドの吐出異常検出・判定方法 |
Country Status (3)
Country | Link |
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EP (1) | EP1600294A4 (ja) |
JP (1) | JP3794431B2 (ja) |
WO (1) | WO2004076180A1 (ja) |
Cited By (10)
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JP2009226616A (ja) * | 2008-03-19 | 2009-10-08 | Seiko Epson Corp | 流体吐出装置及びノズル検査方法 |
JP2011240563A (ja) * | 2010-05-18 | 2011-12-01 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
JP2011240561A (ja) * | 2010-05-18 | 2011-12-01 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
US8777347B2 (en) | 2011-04-13 | 2014-07-15 | Seiko Epson Corporation | Liquid discharging apparatus, inspection method, and medium having recorded program |
JP2014156129A (ja) * | 2014-04-30 | 2014-08-28 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
KR101475251B1 (ko) * | 2007-02-13 | 2014-12-22 | 무사시 엔지니어링 가부시키가이샤 | 누액 검지 기구 및 이것을 구비한 액체 재료 도포 장치 |
US9126402B2 (en) | 2013-09-04 | 2015-09-08 | Canon Kabushiki Kaisha | Ink jet apparatus and method for controlling ink jet apparatus |
US9132627B2 (en) | 2011-02-16 | 2015-09-15 | Seiko Epson Corporation | Liquid ejecting device, inspection method, and program |
US10940686B2 (en) | 2018-09-11 | 2021-03-09 | Seiko Epson Corporation | Integrated circuit device and liquid droplet ejection device |
JP7463721B2 (ja) | 2019-12-26 | 2024-04-09 | セイコーエプソン株式会社 | ヘッドユニット |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2011104824A (ja) * | 2009-11-16 | 2011-06-02 | Seiko Epson Corp | 液体噴射装置、及び、その制御方法 |
JP2011240564A (ja) | 2010-05-18 | 2011-12-01 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
JP2011240560A (ja) | 2010-05-18 | 2011-12-01 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
JP5794346B2 (ja) * | 2014-04-24 | 2015-10-14 | セイコーエプソン株式会社 | 液体吐出装置 |
JP6547422B2 (ja) * | 2014-06-10 | 2019-07-24 | 株式会社リコー | 液滴吐出装置、液滴吐出方法、プログラム、及びインクジェット記録装置 |
JP6883380B2 (ja) | 2015-08-27 | 2021-06-09 | セイコーエプソン株式会社 | 液体噴射装置、制御装置、記録システム及びプログラム |
JP2019037906A (ja) * | 2017-08-22 | 2019-03-14 | 東芝テック株式会社 | 薬液吐出装置及び薬液滴下装置 |
JP7246216B2 (ja) | 2019-03-19 | 2023-03-27 | エスアイアイ・プリンテック株式会社 | 液体噴射ヘッドおよび液体噴射記録装置 |
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- 2004-02-27 WO PCT/JP2004/002390 patent/WO2004076180A1/ja not_active Application Discontinuation
- 2004-02-27 JP JP2005502958A patent/JP3794431B2/ja not_active Expired - Lifetime
- 2004-02-27 EP EP04715497A patent/EP1600294A4/en not_active Withdrawn
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JPS63141750A (ja) * | 1986-12-03 | 1988-06-14 | Seiko Epson Corp | インクジエツト記録ヘツドの気泡検出装置 |
JPH11334102A (ja) * | 1998-05-25 | 1999-12-07 | Mitsubishi Electric Corp | インクジェット式プリンタ、気泡検出回路及び気泡検出方法 |
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Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
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KR101475251B1 (ko) * | 2007-02-13 | 2014-12-22 | 무사시 엔지니어링 가부시키가이샤 | 누액 검지 기구 및 이것을 구비한 액체 재료 도포 장치 |
JP2009226616A (ja) * | 2008-03-19 | 2009-10-08 | Seiko Epson Corp | 流体吐出装置及びノズル検査方法 |
JP2011240563A (ja) * | 2010-05-18 | 2011-12-01 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
JP2011240561A (ja) * | 2010-05-18 | 2011-12-01 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
US9132627B2 (en) | 2011-02-16 | 2015-09-15 | Seiko Epson Corporation | Liquid ejecting device, inspection method, and program |
US8777347B2 (en) | 2011-04-13 | 2014-07-15 | Seiko Epson Corporation | Liquid discharging apparatus, inspection method, and medium having recorded program |
US9126402B2 (en) | 2013-09-04 | 2015-09-08 | Canon Kabushiki Kaisha | Ink jet apparatus and method for controlling ink jet apparatus |
JP2014156129A (ja) * | 2014-04-30 | 2014-08-28 | Seiko Epson Corp | 液体吐出装置、及び、吐出検査方法 |
US10940686B2 (en) | 2018-09-11 | 2021-03-09 | Seiko Epson Corporation | Integrated circuit device and liquid droplet ejection device |
JP7463721B2 (ja) | 2019-12-26 | 2024-04-09 | セイコーエプソン株式会社 | ヘッドユニット |
Also Published As
Publication number | Publication date |
---|---|
EP1600294A1 (en) | 2005-11-30 |
JP3794431B2 (ja) | 2006-07-05 |
JPWO2004076180A1 (ja) | 2006-06-01 |
EP1600294A4 (en) | 2006-08-30 |
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