JP2007301905A - Liquid injection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid injection device that suppresses running costs while effectively consuming liquid, and its manufacturing method. <P>SOLUTION: The liquid injection device is provided with a head unit 2, which has a liquid injection head having a liquid channel including a pressure chamber communicating with nozzles so as to discharge liquid-droplets from the nozzles while imparting pressure to the liquid in the pressure chamber, a suction device 42, which performs a suction operation for discharging the liquid in the pressure chamber while sucking inside the pressure chamber from the nozzles with a prescribed suction force, and an adjusting means for adjusting the suction force generated by the suction device 42 corresponding to at least an environmental barometric pressure at a place where the device is used. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus including a liquid ejecting head that applies pressure to a liquid in a pressure chamber and ejects liquid droplets from a nozzle.

  As a liquid ejecting apparatus having a liquid ejecting head for ejecting liquid droplets from a nozzle, there is an ink jet recording apparatus having an ink jet recording head for ejecting ink droplets. Machine. As an ink jet recording head, for example, a liquid is boiled by a heating element or the like, and a liquid droplet is ejected by a bubble pressure generated at that time, or a volume of a pressure chamber filled with the liquid droplet is changed by a displacement of a piezoelectric element. There are some which discharge droplets from a nozzle by expanding or contracting. Further, for example, there is a device in which droplets are ejected from a nozzle by changing the volume of a pressure chamber using electrostatic force.

  For example, an electrostatic drive type ink jet recording head includes a nozzle plate in which a plurality of nozzles are formed, an ink cavity (pressure chamber) and an ink reservoir (common liquid chamber) communicating with the nozzles. The ink cavity is formed by attaching a cavity plate having a flexible electrode on the bottom surface and an electrode substrate having individual electrodes (fixed electrodes) arranged facing the flexible electrode at regular intervals. And an ink reservoir communicate with each other via an ink supply path (supply port) formed in the nozzle plate (see, for example, Patent Document 1).

  Since such an ink jet recording head ejects ink droplets from a nozzle onto a recording medium, for example, the ink is ejected due to thickening of ink near the nozzle or the presence of bubbles in the ink. There is a problem that defects occur. For this reason, in an ink jet recording apparatus, generally, a suction operation for discharging ink from a nozzle by sucking the inside of the cap with the cap member pressed against the surface of the nozzle plate, that is, by sucking the inside of the ink cavity. (For example, refer to Patent Document 2).

  Here, the remaining amount of ink in the ink supply means such as an ink cartridge is generally obtained by calculation. For example, when a suction operation is performed, the ink remaining amount is obtained by cumulatively subtracting a preset ink consumption (set consumption) corresponding to one suction operation from the total liquid amount of the ink supply means. Is calculated. For example, the ink supply means needs to be replaced based on the calculated ink remaining amount.

  Further, in the above-described suction operation, even when the implementation conditions are constant, the ink flow rate changes depending on the environmental pressure or the environmental temperature at the place of use, so that the amount of ink consumed in the suction operation changes depending on the place of use. For example, when the environmental pressure increases, the flow rate increases, so the consumption increases. Conversely, when the environmental pressure decreases, the flow rate decreases, and the consumption decreases. Furthermore, in the suction operation, it is necessary to discharge the ink from the nozzle at a flow rate of a certain value or more. Therefore, the suction operation condition is that the ink consumption is small, specifically, use in a low pressure, low temperature environment. It is set according to. Further, the set consumption amount used for calculating the remaining amount of ink is set according to use in a high atmospheric pressure and high temperature environment when the consumption amount is maximized.

  For this reason, for example, when the recording apparatus is used in a low-pressure and low-temperature environment, the set consumption amount is considerably larger than the actual consumption amount, and the ink remaining amount calculated by the ink supply means and the actual ink remaining amount The problem that does not match. Specifically, the ink supply means must be replaced even though there is still usable ink in the ink supply means, and the ink must be wasted, which increases the running cost. There is a problem of end.

  Needless to say, such a problem also exists in a liquid ejecting apparatus including a liquid ejecting head that ejects liquid droplets other than ink droplets.

Japanese Patent Laid-Open No. 11-198386 (Claims, FIG. 1 etc.) JP 2004-330750 A (paragraph [0040] etc.)

  In view of such circumstances, it is an object of the present invention to provide a liquid ejecting apparatus that can effectively consume liquid and that can reduce running costs, and a manufacturing method thereof.

A first aspect of the present invention that solves the above problem is a liquid ejecting head that has a liquid flow path including a pressure chamber communicating with a nozzle, applies pressure to the liquid in the pressure chamber, and ejects liquid droplets from the nozzle. And a suction means for performing a suction operation for sucking the pressure chamber from the nozzle with a predetermined suction force and discharging the liquid in the pressure chamber, and at least according to the atmospheric pressure of the place of use. The liquid ejecting apparatus includes an adjusting unit that adjusts the suction force of the suction unit.
In the first aspect, the difference between the minimum value and the maximum value of the liquid consumption during the suction operation is extremely small regardless of the change in the environmental atmospheric pressure at the place of use. Thereby, the liquid consumption can be suppressed to the minimum necessary while ensuring the minimum flow velocity that can surely discharge the bubbles mixed in the liquid in the pressure chamber. Further, since the difference between the calculated liquid remaining amount and the actual liquid remaining amount of the liquid supply means becomes small, the liquid in the liquid supply means can be used efficiently.

The second aspect of the present invention further includes an atmospheric pressure detection unit that detects an environmental atmospheric pressure of a use environment, and the adjustment unit adjusts the suction force of the suction unit according to the environmental atmospheric pressure detected by the atmospheric pressure detection unit. The liquid ejecting apparatus according to the first aspect is characterized by adjusting.
In the second aspect, since the ambient atmospheric pressure at the place of use is detected by the atmospheric pressure detection means provided in the recording apparatus, the suction force of the suction means can be adjusted more accurately without trouble. Therefore, the difference between the minimum value and the maximum value of the liquid consumption amount during the suction operation is more reliably reduced regardless of the change in the ambient atmospheric pressure at the place of use.

The third aspect of the present invention further comprises input means for inputting the altitude of the use environment, and atmospheric pressure calculating means for calculating the environmental atmospheric pressure from the altitude input by the input means, wherein the adjusting means includes the atmospheric pressure. The liquid ejecting apparatus according to the first aspect is characterized in that the suction force by the suction means is adjusted in accordance with the ambient atmospheric pressure calculated by the calculation means.
In the third aspect, the accurate altitude is input, so that the atmospheric pressure at the place of use can be calculated relatively easily and accurately. As a result, the difference between the minimum value and the maximum value of the liquid consumption during the suction operation is more reliably reduced regardless of the change in the ambient atmospheric pressure at the place of use.

According to a fourth aspect of the present invention, the liquid ejecting head is driven between a flexible electrode provided on one surface of the pressure chamber and a fixed electrode disposed to face the flexible electrode at a predetermined interval. An actuator for applying a voltage pulse and causing the flexible electrode to vibrate by an electrostatic force generated between them, and further calculating an atmospheric pressure from an electrostatic capacity of the actuator; The liquid ejecting apparatus according to the first aspect is characterized in that the adjusting means adjusts the suction force by the suction means in accordance with the ambient atmospheric pressure calculated by the atmospheric pressure calculation means.
In the fourth aspect, the atmospheric pressure at the place of use is calculated from the capacitance of the actuator of the recording apparatus, so that the suction force of the suction means can be adjusted more accurately and without trouble. Therefore, the difference between the minimum value and the maximum value of the liquid consumption amount during the suction operation is more reliably reduced regardless of the change in the ambient atmospheric pressure at the place of use.

In a fifth aspect of the present invention, the liquid ejecting head is driven between a flexible electrode provided on one surface of the pressure chamber and a fixed electrode disposed to face the flexible electrode at a predetermined interval. An atmospheric pressure calculation that includes an actuator that applies a voltage pulse and vibrates the flexible electrode by electrostatic force generated between them, and calculates an atmospheric pressure from a residual vibration waveform of the flexible electrode. The liquid ejecting apparatus according to the first aspect is further characterized in that the adjusting unit adjusts the suction force by the suction unit in accordance with the ambient atmospheric pressure calculated by the atmospheric pressure calculating unit.
In the fifth aspect, the ambient atmospheric pressure at the place of use is calculated from the residual vibration waveform of the actuator of the recording apparatus, so that the suction force of the suction means can be adjusted more accurately without trouble. Therefore, the difference between the minimum value and the maximum value of the liquid consumption amount during the suction operation is more reliably reduced regardless of the change in the ambient atmospheric pressure at the place of use.

According to a sixth aspect of the present invention, in the environment temperature range in which the pressure chamber is sucked at a constant pressure when the adjusting means performs the sucking operation, suction by the suction means is performed according to the ambient atmospheric pressure at the place of use. Adjusting the force and adjusting the suction force by the suction means according to the environment temperature of the place of use in the range of the environment temperature where the pressure chamber is sucked in a fixed amount when the suction operation is executed. The liquid ejecting apparatus according to any one of the first to fifth aspects.
In the sixth aspect, the suction amount of the suction means is adjusted according to the difference in use state of the suction means depending on the usage environment of the recording apparatus. Thereby, the suction force of the suction means is adjusted to a state more suitable for the use environment. Therefore, the difference between the minimum value and the maximum value of the liquid consumption during the suction operation is more reliably reduced regardless of the change in the environmental condition of the place of use.

The seventh aspect of the present invention further includes temperature detecting means for detecting the environmental temperature of the place of use, and the adjusting means is responsive to the environmental temperature of the place of use detected by the temperature detecting means together with the environmental pressure of the place of use. In the liquid ejecting apparatus according to the sixth aspect, the suction force of the suction means is adjusted.
In the seventh aspect, the suction force of the suction means is adjusted to a state more suitable for the use environment and without trouble.

An eighth aspect of the present invention is the liquid ejecting apparatus according to any one of the first to seventh aspects, wherein the adjustment of the suction force of the suction means is adjustment of a suction speed by the suction means.
In the eighth aspect, by adjusting the suction speed of the suction means, the difference between the minimum value and the maximum value of the liquid consumption during the suction operation is more reliably reduced regardless of the change in the environmental condition of the place of use. Become.

According to a ninth aspect of the present invention, the suction means sucks the pressure chamber by a tube pump, and the adjustment of the suction force of the suction means is adjustment of the rotation speed of the tube pump. In the liquid ejecting apparatus according to the eighth aspect.
In the ninth aspect, by adjusting the rotation speed of the tube pump, the difference between the minimum value and the maximum value of the liquid consumption during the suction operation is more reliably reduced regardless of the change in the environmental condition of the place of use. Become.

According to a tenth aspect of the present invention, in the liquid jet according to the eighth or ninth aspect, the adjustment of the suction force of the suction means is an adjustment of the suction time by the suction means in one suction operation. In the device.
In the tenth aspect, by further adjusting the suction time, the difference between the minimum value and the maximum value of the liquid consumption amount during the suction operation is more reliably reduced regardless of the change in the environmental condition at the place of use.

In an eleventh aspect of the present invention, the suction means sucks the pressure chamber by a tube pump, and the suction force of the suction means is adjusted by the number of rotations of the tube pump in one suction operation. In the liquid ejecting apparatus according to the tenth aspect, the adjustment is performed.
In the eleventh aspect, by adjusting the rotation speed (rotation time) of the tube pump, the difference between the minimum value and the maximum value of the liquid consumption amount during the suction operation can be obtained regardless of the change in the environmental condition of the place of use. Smaller surely.

  Hereinafter, the present invention will be described based on embodiments.

(Embodiment 1)
FIG. 1 is a schematic perspective view of a liquid ejecting apparatus according to Embodiment 1 of the invention.
The liquid ejecting apparatus of the present embodiment is an ink jet recording apparatus (hereinafter referred to as a recording apparatus) 1 having an ink jet recording head (hereinafter referred to as a recording head) that discharges ink droplets. As shown in FIG. The head unit 2 (2A and 2B) having the ink cartridge 3 (3A and 3B) constituting the ink supply means is detachably provided, and the carriage 4 on which the head unit 2 is mounted is attached to the apparatus main body 5. The carriage shaft 6 is provided so as to be movable in the axial direction. The head units 2A and 2B eject a black ink composition and a color ink composition, respectively.

  A drive motor 7 is provided in the vicinity of one end of the carriage shaft 6, and a first pulley 7 a having a groove on the outer periphery is provided at the tip of the shaft of the drive motor 7. Further, a second pulley 7b corresponding to the first pulley 7a of the drive motor 7 is rotatably provided in the vicinity of the other end portion of the carriage shaft 6, and the first pulley 7a and the second pulley are provided. A timing belt 8 made of an elastic member such as rubber is hung between the belt 7b.

  Then, the driving force of the driving motor 7 is transmitted to the carriage 4 via the timing belt 8, so that the carriage 4 on which the head unit 2 is mounted is moved along the carriage shaft 6. On the other hand, the apparatus body 5 is provided with a platen 9 along the carriage 4. The platen 9 can be rotated by a driving force of a paper feed motor (not shown), and a recording sheet S which is a recording medium such as paper fed by a paper feed roller is wound around the platen 9 and conveyed. It has become so.

  Further, in a non-printing area on the side of the platen 9 that is the end of the carriage 4 in the moving direction, as will be described in detail later, cleaning is a suction unit that performs a suction operation for sucking ink near the nozzles of the recording head. A device 40 is provided.

  Next, the configuration of the recording head according to the first embodiment will be described. FIG. 2 is a schematic perspective view of the recording head, and FIG. 3 is a cross-sectional view thereof. The recording head 10 according to the present embodiment is a so-called electrostatic drive type recording head, and includes a cavity substrate 11 and a nozzle plate 20 and an electrode substrate 30 respectively bonded to both surfaces of the cavity substrate 11. .

  The cavity substrate 11 is made of, for example, a silicon single crystal substrate having a plane orientation (110), and a plurality of pressure chambers (cavities) 12 opened on one side thereof are arranged in the width direction. In the present embodiment, as shown in FIG. 2, the cavity substrate 11 is formed with two rows in which a plurality of pressure chambers 12 are arranged in parallel. Further, the cavity substrate 11 is formed with a common ink chamber 13 serving as an ink chamber (reservoir) common to the pressure chambers 12 in each row. The common ink chamber 13 is connected via an ink supply path described later. The pressure chambers 12 communicate with each pressure chamber 12. An ink supply hole 14 for supplying ink to the common ink chamber 13 is formed on the bottom wall of the common ink chamber 13. The cavity substrate 11 is formed with a through hole 15 on the outside of the common ink chamber 13 for exposing an individual terminal portion connected to an individual electrode described later. The through hole 15 may be continuously formed up to the end surface of the cavity substrate 11 opposite to the common ink chamber 13.

  Note that the bottom wall of each pressure chamber 12 functions as a diaphragm 16 for applying pressure to the pressure chamber 12 and also serves as a common electrode for generating an electrostatic force that displaces the diaphragm 16. Also serves as. That is, the diaphragm 16 functions as a flexible electrode that constitutes an actuator for applying pressure to the pressure chamber 12. In the vicinity of the through hole 15 of the cavity substrate 11, a common terminal portion 17 is formed which is exposed in an exposure hole described later of the nozzle plate 20 and is connected to a drive wiring (not shown).

  The nozzle plate 20 is made of, for example, a silicon single crystal substrate having a plane orientation (100), and a plurality of nozzles 21 communicating with the pressure chambers 12 are formed. The nozzle plate 20 is bonded to the opening surface side of the cavity substrate 11 to form one surface of the pressure chamber 12 and the common ink chamber 13. Further, a nozzle step portion 22 is formed on the surface of the nozzle plate 20 opposite to the cavity substrate 11 by removing a part in the thickness direction over a region corresponding to the nozzle 21.

  Here, each nozzle 21 is provided on the ink droplet ejection side and has a substantially circular small-diameter portion 21a that opens into the nozzle step portion 22, and has a diameter larger than that of the small-diameter portion 21a. The large-diameter portion 21 b communicates with the chamber 12. All the nozzles 21 (small-diameter portions 21a) are opened in the nozzle step portion 22, and in this embodiment, the surface of the nozzle plate 20 in the nozzle step portion 22 is a nozzle surface.

  In addition, on the joint surface of the nozzle plate 20 with the cavity substrate 11, an ink supply that communicates each of the pressure chambers 12 and the common ink chamber 13 with a region corresponding to the boundary between the pressure chamber 12 and the common ink chamber 13. A path 23 is formed. The nozzle plate 20 is formed with an exposure hole 24 that communicates with the through hole 15 of the cavity substrate 11 at a position corresponding to the outside of the common ink chamber 13 and exposes the common terminal portion 17 together with the individual terminal portion described later. ing. The exposure hole 24 may be formed continuously up to the end surface opposite to the common ink chamber 13, similarly to the through hole 15.

  Further, a liquid repellent film 25 made of a water / oil repellent material made of, for example, a fluorine-containing silane coupling compound is formed on the surface of the nozzle plate 20, in the present embodiment, in the nozzle step portion 22. Thereby, adhesion of ink droplets to the surface (nozzle surface) of the nozzle plate 20 is suppressed.

  On the other hand, the electrode substrate 30 is made of a glass substrate such as borosilicate glass having a thermal expansion coefficient close to that of a silicon single crystal substrate, and is bonded to the surface of the cavity substrate 11 on the vibration plate 16 side. A groove 31 corresponding to each pressure chamber 12 is formed in a region of the electrode substrate 30 facing the diaphragm 16. In addition, an ink introduction hole 32 communicating with the ink supply hole 14 is formed in the electrode substrate 30 at a position corresponding to the ink supply hole 14 of the cavity substrate 11. The common ink chamber 13 is filled with ink from an ink supply means such as an ink cartridge (not shown) through the ink introduction hole 32 and the ink supply hole 14.

  In each groove 31, individual electrodes 33, which are fixed electrodes for generating an electrostatic force that displaces the diaphragm 16, are arranged in a state where a predetermined interval is secured between the diaphragms 16. . In the groove 31, an individual terminal portion 34 to which a drive wiring (not shown) is connected is formed in a region facing the through hole 15 of the cavity substrate 11, and the individual terminal portion 34 and each individual electrode 33 are connected to each other. Are connected by a lead electrode 35. Although not shown, each individual electrode 33 and the lead electrode 35 are sealed with an insulating film, and a driving voltage pulse is applied between the individual terminal portion 34 and the common terminal portion 17 via a connection wiring. For this purpose, an oscillation circuit is connected.

  In such a recording head 10, when a drive voltage pulse is applied to an actuator composed of the individual electrode 33 and the diaphragm 16 (cavity substrate 11) by an oscillation circuit, a gap between the individual electrode 33 and the diaphragm 16 is obtained. When the diaphragm 16 is bent and deformed to the individual electrode 33 side by the electrostatic force generated in the pressure, the volume of the pressure chamber 12 is expanded and the application of the driving voltage is released, the diaphragm 16 returns to the original state, and the pressure chamber 12 volumes contract. Then, due to the pressure change in the pressure chamber 12 generated at this time, a part of the ink in the pressure chamber 12 is ejected from the nozzle 21 as an ink droplet.

  Further, as described above, the recording apparatus 1 equipped with such a head unit 2 having the recording head 10 is provided with a cleaning device 40 as a suction means in a non-printing area (see FIG. 1). The cleaning device 40 performs a suction operation at a predetermined timing. The suction operation is an operation of sucking the pressure chamber 12 from the nozzle 21 with a predetermined suction force to discharge the ink in the pressure chamber 12 from the nozzle 21, thereby preventing the occurrence of printing defects. .

  As shown in FIG. 4, the suction cap 41 constituting the cleaning device 40 according to the present embodiment opposes the nozzle plate 20 of the recording head 10, and removes all of the plurality of nozzles 21 formed in the nozzle plate 20. It is provided to cover. Specifically, the suction cap 41 has a suction port 41 a on the surface facing the nozzle plate 20, and the edge of the suction port 41 a abuts the surface of the nozzle plate 20, so that all of the nozzles 21 are placed. It comes to cover. The suction cap 41 is provided with a communication port 41b communicating with the suction port 41a on the surface opposite to the suction port 41a. A suction device 42 is connected to the communication port 41b via a suction tube 43. .

  The suction device 42 is not particularly limited as long as the suction chamber 42 can suck the inside of the pressure chamber 12 with a suction force at which a predetermined flow velocity can be obtained during the suction operation. For example, in this embodiment, a tube pump is used. ing. As shown in FIG. 5, for example, the suction device 42 that is a tube pump includes a pump frame 45 having a tube support surface 45a that regulates the outer shape of the flexible tube 44 in an arc shape, and a drive (not shown) such as a stepping motor. The pump wheel 47 is rotated by a drive shaft 46 connected to the means, and two rollers 48 are rotatably attached to the peripheral edge of the pump wheel 47. In such a suction device 42, the flexible tube 44 is sequentially crushed by each roller 48 by rotating the pump wheel 47 about the drive shaft 46, and thereby the inside of the pressure chamber 12 is sucked. It has become so.

  The operation of the cleaning device 40 is controlled by a suction control unit, which will be described later, so that the above-described suction operation is executed at a predetermined timing such as when the power is turned on or during printing. Specifically, with the suction cap 41 in close contact with the nozzle plate 20, the suction device 42, which is a tube pump, makes the suction port 41 a negative and sucks the pressure chamber 12 with a predetermined suction force. Then, the ink in the pressure chamber 12 is discharged from the nozzle 21. Thereby, the thickened ink in the vicinity of the nozzle 21 in the pressure chamber 12, the bubbles mixed in the ink, and the like can be discharged from the nozzle 21, and the occurrence of printing failure can be prevented.

  Further, as will be described in detail later, in the present invention, the suction force of the cleaning device 40 (suction device 42) that performs such a suction operation is adjusted in accordance with the ambient atmospheric pressure at the place where the recording device 1 is used.

  FIG. 6 is a functional block diagram of the recording apparatus. As shown in FIG. 6, the recording apparatus 1 according to this embodiment includes a recording head 10 that is a mechanism unit that actually performs printing, and a cleaning apparatus that includes a suction device 42 that sucks ink near the nozzles 21 of the recording head 10. 40, and a control unit 50 for controlling the operations of the recording head 10 and the cleaning device 40. Further, in the present invention, an atmospheric pressure detecting means 60 for detecting the ambient atmospheric pressure at the place where the recording device 1 is used is provided. The control unit 50 includes a print control unit 51, a recording head drive circuit 52, a print position control unit 53, a suction control unit 54, an adjustment unit 55, and a calculation unit 56.

  The suction control unit 54 controls the operation of the cleaning device 40 to perform a suction operation for sucking ink in the vicinity of the nozzles 21 of the recording head 10. Specifically, the suction control unit 54 moves the recording head 10 to a position facing the suction cap 41 via the printing position control unit 53, and caps the recording head 10 with the suction cap 41. As will be described in detail later, the suction control unit 54 drives the suction device 42 based on the driving conditions stored in the storage unit 57 provided in the control unit 50 and the like, so that the inside of the pressure chamber 12 is generated with a predetermined suction force. A suction operation for sucking is performed. Thereby, ink consumption can be suppressed and ink can be used effectively.

  The print control unit 51 controls the printing operation of the recording head 10 and, for example, controls the driving of the recording head 10 via the recording head driving circuit 52 in accordance with the input of a print signal, thereby ejecting ink droplets from the nozzles 21. . The printing position control means 53 positions the recording head 10 in the main scanning direction and the sub scanning direction during printing or the like. Specifically, the printing position control means 53 drives the drive motor 7 to move the carriage 4 in the main scanning direction to position the recording head 10 in the main scanning direction, and drives a paper feed motor (not shown) to drive the platen. 9 is rotated to move the recording sheet S in the sub-scanning direction, thereby positioning the recording head 10 with respect to the recording sheet S in the sub-scanning direction.

  The adjusting unit 55 adjusts the suction force of the suction device 42 constituting the cleaning device 40 according to the ambient atmospheric pressure detected by the atmospheric pressure detection unit 60. For example, when the atmospheric pressure detection unit 60 detects the ambient atmospheric pressure at a predetermined timing, such as when the power is turned on, and the atmospheric pressure detection unit 60 detects the ambient atmospheric pressure, the adjustment unit 55 performs cleaning according to the ambient atmospheric pressure. The suction force of the device 40 is adjusted. For example, in the present embodiment, the driving condition of the suction device 42 (the driving condition of the driving unit of the suction device 42) is adjusted and stored in the storage unit 57. As described above, the suction control unit 54 drives the suction device 42 based on the adjusted driving condition stored in the storage unit 57, so that the suction force is adjusted. For example, in this embodiment, the adjustment means 55 adjusts a rotational speed as a drive condition of the suction device 42 which is a tube pump. A method for adjusting the rotation speed of the suction device 42 will be described later in detail. The atmospheric pressure detection means 60 is not particularly limited as long as it can detect the environmental atmospheric pressure. For example, a barometer using a semiconductor pressure sensor or the like is preferably used.

  Further, the calculation unit 56 calculates the remaining amount of ink in the ink supply unit (ink cartridge) based on conditions such as the number of ink droplet ejections during printing and the number of times of suction operation. For example, in the case of a suction operation, a calculated ink consumption amount consumed in one suction operation is set in advance. Then, when performing the suction operation, the calculation unit 56 accumulates the calculated ink consumption (hereinafter referred to as “set consumption”) from the total ink amount of the ink supply unit according to the number of suction operations. The remaining amount of ink in the ink supply means is calculated by subtracting them. Further, for example, when the ink supply unit reaches a predetermined ink remaining amount, the user is prompted to replace the ink supply unit by, for example, lighting an ink replacement lamp.

  In such a recording apparatus 1 according to the present invention, the suction force by the cleaning device (suction means) 40 when performing the suction operation is set based on the channel resistance value (R value) of the ink channel of the recording head 10. Has been. The setting of the suction force of the cleaning device 40 is, for example, the setting of the flow rate (suction speed) in the suction tube 43 when the suction operation is executed, the time for performing one suction operation (suction time), and the like. To do.

  The operation of such an ink jet recording apparatus, specifically, the operation of adjusting the rotational speed of the suction device 42 will be described below.

  First, when the recording apparatus 1 is turned on, the atmospheric pressure detection means 60 detects the ambient atmospheric pressure at the place where the recording apparatus 1 is used. For example, the ambient atmospheric pressure is about 1060 (hPa) at a location of 0 (m) above sea level, and the ambient atmospheric pressure is about 770 (hPa) at a location of 2000 (m) above sea level. The timing at which the atmospheric pressure detection unit 60 detects the ambient atmospheric pressure is not particularly limited. For example, the atmospheric pressure detection unit 60 may detect the atmospheric pressure every time the power is turned on. It is preferable to carry out the above.

  When the atmospheric pressure detection means 60 detects the environmental atmospheric pressure, the adjustment means 55 adjusts the rotation speed of the suction device 42 constituting the cleaning device 40 based on the environmental atmospheric pressure. Specifically, a table in which the ambient pressure and the reference value of the pump setting for determining the rotational speed of the suction device 42, the coefficient of the pump setting value, and the like are associated with each other as shown in Table 1 below is stored in the storage unit 57. . When the atmospheric pressure detecting means 60 detects the environmental atmospheric pressure, the adjusting means 55 selects (calculates) the rotation speed (pump set value) of the suction device 42 suitable for the environmental atmospheric pressure based on this table, and the control unit 50 Is written in the storage unit 57. It goes without saying that the table may be one in which the ambient pressure and the pump set value (rotational speed) corresponding to each rank of ambient pressure are associated with each other.

  Here, in this embodiment, since the driving means of the suction device 42 is a stepping motor, as shown in Table 1 above, as a value for setting the rotational speed (pump setting reference value), for example, every second The number of steps pa_01 to pa_400 is set. The ambient pressure is divided into a plurality of ranks A to F (A: high atmospheric pressure side) according to the numerical range, and for each rank, the pump set value coefficient is the pump set reference value pa_01 to pa_400. It is set corresponding to each. It should be noted that it is preferable to narrow the numerical range in each rank of the environmental atmospheric pressure in the atmospheric pressure region where the frequency of use is high or in the atmospheric pressure region where the change in ink consumption is large. When the atmospheric pressure detecting means 60 detects the environmental atmospheric pressure, the adjusting means 55 selects a coefficient of the pump set value corresponding to the rank of the environmental atmospheric pressure detected by the atmospheric pressure detecting means 60 from such a table, and the selected coefficient And the pump setting value (rotational speed) calculated from the pump setting reference value is written in the storage unit 57 of the control unit 50. For example, when the atmospheric pressure detected by the atmospheric pressure detection unit 60 is rank C, the adjustment unit 55 multiplies the reference values pa_01 to pa_400 by coefficients corresponding to the reference values pa_01 to pa_400, for example, pa_01 × 1.4, pa_02 ×. 1.3 or the like is written in the storage unit 57 of the control unit 50 as a pump set value.

  Then, when performing the suction operation, the suction control means 54 controls the driving of the suction device 42 that is a tube pump based on the pump set value stored in the storage unit 57.

  In this way, by changing the setting of the rotation speed of the suction device 42 for each recording device 1 based on the ambient pressure, that is, by changing the suction force, the ink consumption due to the suction operation is changed by the change in the ambient pressure. Accordingly, for example, as shown by a solid line in FIG. 7, the difference between the minimum value C1 and the maximum value C2 of the ink consumption is extremely small. On the other hand, in the conventional recording apparatus, the ink consumption amount due to the suction operation increases as the ambient air pressure increases as shown by the dotted line in FIG. 7, and therefore, the minimum value C1 and the maximum value C2 ′ of the ink consumption amount The difference is considerably larger than that of the recording apparatus according to the present invention.

  In the present invention, the difference between the minimum value C1 and the maximum value C2 of the ink consumption amount in the suction operation is thus reduced, so that the air bubbles mixed in the ink in the pressure chamber 12 can be surely discharged. However, since the ink consumption can be suppressed to the minimum necessary while ensuring the lowest possible flow rate, the life of the ink cartridge (ink supply means) can be extended.

  The “set consumption” described above is set to the maximum value C2 of the actual ink consumption. For this reason, the difference between the calculated ink remaining amount of the ink supply means and the actual ink remaining amount is reduced. Thereby, the ink in an ink supply means (ink cartridge) can be used efficiently. That is, the ink in the ink supply means can be used almost completely. Therefore, a liquid ejecting apparatus with reduced running cost can be realized.

  In this embodiment, the rotation speed of the suction device 42 is adjusted as the adjustment of the suction speed of the suction means based on the ambient pressure. However, the rotation speed of the suction device 42 is adjusted as the suction time of the suction means. (Rotation time) may be further adjusted. Thereby, the ink in an ink supply means can be utilized more effectively.

(Embodiment 2)
FIG. 8 is a functional block diagram of the recording apparatus according to the present embodiment. In the first embodiment, the atmospheric pressure detection means 60 provided in the recording apparatus 1 detects the environmental atmospheric pressure. However, in the present embodiment, the environmental atmospheric pressure is calculated based on the altitude of the place of use input by the user. This is an example. That is, as shown in FIG. 8, the recording apparatus according to the present embodiment includes an input unit 70 for a user to input the altitude of the usage location of the recording apparatus, instead of the atmospheric pressure detection unit, and is used by the control unit 50. It is the same as that of Embodiment 1 except having the atmospheric pressure calculation means 58 for calculating the ambient atmospheric pressure of the place.

  The input means 70 is, for example, an operation unit that is provided on the front surface of the apparatus main body and includes, for example, various parameters, various keys for instructing printing, etc. In this embodiment, the altitude of the place of use is input. Can be done. In addition, the atmospheric pressure calculation unit 58 calculates the ambient atmospheric pressure at the place of use based on the altitude input from the input unit 70, for example. Specifically, the storage unit 57 of the control unit 50 stores in advance a table or mathematical expression in which the altitude is associated with the ambient atmospheric pressure. When the altitude is input from the input unit 70 by the user, the atmospheric pressure calculation unit 58 refers to the table or the mathematical formula stored in the storage unit 57 and calculates the environmental atmospheric pressure at the place of use.

  Then, the adjusting means 55 adjusts the driving conditions such as the rotational speed of the suction device 42 in accordance with the environmental atmospheric pressure calculated by the atmospheric pressure calculating means 58 instead of the environmental atmospheric pressure detected by the atmospheric pressure detecting means 60 described above.

  It goes without saying that the same effects as those of the first embodiment can be obtained even with such a configuration. Further, by detecting the ambient pressure based on the altitude input by the user, if the correct altitude is input, the ambient pressure can be accurately calculated. Therefore, the driving condition of the suction device 42 can be adjusted relatively easily to an optimum state for the ambient atmospheric pressure.

  In this embodiment, an input unit for inputting the altitude is provided in the apparatus main body, but the altitude can be input on the computer side connected to the recording apparatus 1 without providing such an input unit. It may be. That is, “elevation” may be provided as a setting item by a computer control program (printer driver) or the like.

(Embodiment 3)
FIG. 9 is a functional block diagram of the recording apparatus according to the third embodiment. In the second embodiment, the atmospheric pressure calculation unit 58 calculates the ambient atmospheric pressure at the place of use based on the altitude input from the input unit 70 or the like. However, in this embodiment, the atmospheric pressure calculation unit 58 uses the recording head. This is an example in which the ambient pressure is calculated from the capacitance of the actuator to be configured, and other configurations are the same as those in the second embodiment.

  Specifically, as shown in FIG. 9, instead of the input means, the capacitance of the actuator, that is, the capacitance for detecting the capacitance between the diaphragm 16 that is a flexible electrode and the individual electrode 33 is detected. It has a detection means 59. Further, the atmospheric pressure calculation means 58 calculates the environmental atmospheric pressure from the capacitance of the actuator detected by the capacitance detection means 80. For example, the atmospheric pressure calculation unit 58 according to the present embodiment calculates the distance (gap) between the diaphragm 16 and the individual electrode 33 from the capacitance of the actuator detected by the capacitance detection unit 80 and stores it in the storage unit 57. Based on the stored table in which the distance and the ambient pressure are associated with each other or a predetermined mathematical formula, the ambient pressure at the place of use is calculated. Then, the adjusting unit 55 adjusts the driving condition of the suction device 42 according to the ambient atmospheric pressure calculated from the capacitance by the atmospheric pressure calculating unit 58.

  Here, the diaphragm 16 is deformed due to the ambient atmospheric pressure in a state where no voltage is applied. For example, when the ambient atmospheric pressure is relatively high, as shown in FIG. 10A, the diaphragm 16 is bent so that the individual electrode 33 side is convex, while when the ambient atmospheric pressure is relatively low. As shown in FIG. 10B, the individual electrode 33 is bent so as to be concave. For this reason, the electrostatic capacitance between the diaphragm 16 and the individual electrode 33 changes according to the ambient atmospheric pressure. Therefore, the ambient atmospheric pressure can be calculated from the capacitance between the diaphragm 16 and the individual electrode 33.

  Even with such a configuration, the same effects as those of the above-described embodiment can be obtained. Further, by calculating the ambient pressure from the capacitance of the actuator, it is possible to obtain the accurate ambient pressure relatively easily.

  In this embodiment, the ambient pressure is calculated from the capacitance of the actuator. For example, the ambient pressure is calculated from the residual vibration waveform after the ink droplet is discharged from the vibration plate 16 (pressure chamber) of the recording head. You may do it. That is, instead of the capacity detection means 80, a vibration detection means for detecting the residual vibration waveform of the diaphragm 16 is provided, and the atmospheric pressure calculation means 58 uses the residual vibration waveform of the diaphragm 16 detected by the vibration detection means to May be detected. Since the residual vibration waveform of the diaphragm 16 also changes with the deformation of the diaphragm 16 described above, the ambient atmospheric pressure can also be accurately calculated from the residual vibration waveform of the diaphragm 16.

(Embodiment 4)
FIG. 11 is a diagram illustrating functional blocks of the recording apparatus according to the fourth embodiment. The present embodiment is an example in which the adjusting means 55 adjusts the suction force of the suction means, for example, the rotation speed of the suction device 42 according to the environmental temperature of the use place, together with the ambient atmospheric pressure of the use place.

  In the present embodiment, as shown in FIG. 11, the apparatus further includes a temperature detection unit 90 configured to detect the environmental temperature of the place of use, for example, a thermistor, and the adjustment unit 55 is based on the conditions described below. Except that the rotational speed of the suction device 42 is adjusted in accordance with either the atmospheric pressure detected by the atmospheric pressure detection means 60 or the environmental temperature detected by the temperature detection means 90, the same as in the first embodiment.

  Here, for example, when the suction operation is performed by the suction device 42 including a tube pump or the like, in a state where the environmental temperature is high and the viscosity of the ink is low, it substantially functions as a metering pump. In a high state, it may function as a constant pressure pump substantially. Of course, the boundary temperature that functions as a constant pressure pump or a metering pump varies depending on the type of ink and the flow path resistance of the ink flow path.

  In the present embodiment, the adjusting means 55 adjusts the rotational speed of the suction device 42 in accordance with either the environmental atmospheric pressure or the environmental temperature depending on the environmental temperature of the place of use. Thereby, further effective use of ink becomes possible.

  Specifically, in the present embodiment, the temperature detection unit 90 detects the environmental temperature of the place of use at a predetermined timing such as when the power is turned on, and the environmental temperature detected by the temperature detection unit 90 executes the suction operation. When the pressure chamber 12 is in a range that is sucked at a constant pressure, the adjusting means 55 rotates the suction device 42 according to the ambient atmospheric pressure detected by the atmospheric pressure detecting means 60 as described in the first embodiment. Adjust speed etc. On the other hand, when the environmental temperature detected by the temperature detection means 90 is within a range in which the pressure chamber 12 is sucked in a fixed amount when the suction operation is executed, the adjustment means 55 detects the environment detected by the temperature detection means 90. The rotational speed of the suction device 42 is adjusted according to the temperature.

  Hereinafter, the adjustment operation of the rotation speed of the suction device 42 when the ambient temperature detected by the temperature detection means 90 is in a range in which the pressure chamber 12 is sucked in a fixed amount when the suction operation is executed will be described. Note that the adjustment operation in the case where the ambient temperature is in a range in which the pressure chamber 12 is sucked at a constant pressure when the suction operation is executed has been described in the first embodiment, and thus the description thereof is omitted here.

  In the present embodiment, together with the table in which the ambient atmospheric pressure and the coefficient of the pump set value described in the first embodiment are associated with each other, the pump temperature setting that determines the ambient temperature and the rotation speed of the suction device 42 as shown in Table 2 below. A table in which the reference value, the pump set value coefficient, and the like are associated is stored in the storage unit 57.

  When the temperature detecting unit 90 detects the ambient temperature, the adjusting unit 55 selects (calculates) the rotation speed (pump set value) of the suction device 42 suitable for the ambient temperature based on this table, and the control unit 50 Is written in the storage unit 57. Such a table may be one in which the environmental temperature is associated with the pump set value (rotational speed) corresponding to the environmental temperature of each rank.

  Here, since the driving means of the suction device 42 is a stepping motor, as shown in Table 2 above, as a value for setting the rotation speed (pump setting reference value), for example, the number of steps pt_01 to pt_400 per second. Are set respectively. The environmental temperature is divided into a plurality of ranks A to D (A: high temperature side) according to the numerical range, and for each rank, the pump set value coefficient is the pump set reference value pt_01 to pt_400. It is set corresponding to each. In the temperature range where the frequency of use is high or the change in ink consumption is large, it is particularly preferable to narrow the numerical range in each rank of the environmental temperature. In this embodiment, the numerical range is increased toward the rank D side. I try to make it narrower. When the temperature detecting unit 90 detects the environmental temperature, the adjusting unit 55 selects the coefficient of the pump set value corresponding to the rank of the environmental temperature detected by the temperature detecting unit 90 from such a table, and the selected coefficient. The pump setting value (rotational speed) calculated from the pump setting reference value is written in the storage unit 57 of the control unit 50. For example, when the environmental temperature detected by the temperature detection unit 90 is rank C, the adjustment unit 55 multiplies the reference values pt_01 to pt_400 by the corresponding coefficients, for example, pt_01 × 1.5, pt_02 ×. 1.7 or the like is written in the storage unit 57 of the control unit 50 as a pump set value.

  Then, when performing the suction operation, the suction control means 54 controls the driving of the suction device 42 that is a tube pump based on the pump set value stored in the storage unit 57.

  In the conventional recording apparatus, when the inside of the pressure chamber 12 is sucked in a fixed amount when the suction operation is executed, the ink consumption due to the suction operation increases the environmental temperature (ink viscosity) as shown by the dotted line in FIG. Increase). For this reason, the difference between the minimum value C1 and the maximum value C2 ′ of the ink consumption due to the suction operation becomes considerably large. On the other hand, in this embodiment, since the setting of the rotation speed of the suction device 42 is adjusted based on the environmental temperature, the ink consumption amount due to the suction operation varies depending on the change in the environmental temperature, for example, FIG. Changes as shown by the solid line. For this reason, the difference between the minimum value C1 and the maximum value C2 of the ink consumption due to the suction operation is extremely small.

  In addition, the difference between the minimum value C1 and the maximum value C2 of the ink consumption amount in the suction operation is reduced in this way, so that the air bubbles mixed in the ink in the pressure chamber 12 can be surely discharged. Since the ink consumption can be suppressed to the minimum necessary while ensuring the flow rate, the life of the ink cartridge (ink supply means) can be extended.

  In addition, since the “set consumption amount” used for calculating the remaining ink amount is set to the maximum value C2 of the actual ink consumption amount, according to this embodiment, the calculated ink remaining amount and the actual ink supply means The difference from the remaining amount of ink becomes smaller. Thereby, the ink in an ink supply means (ink cartridge) can be used efficiently. That is, the ink in the ink supply means can be used almost completely. Therefore, a liquid ejecting apparatus with reduced running cost can be realized.

  Then, as in this embodiment, the adjustment unit 55 sets the “set consumption amount” according to either the environmental atmospheric pressure or the environmental temperature depending on the environmental temperature, so that the suction device 42 is optimal for the usage environment of the recording apparatus. Since the suction operation can be performed by driving under various driving conditions, the ink can be consumed very effectively.

  In the present embodiment, the adjusting unit 55 adjusts the driving condition of the suction device 42 according to the environmental atmospheric pressure detected by the atmospheric pressure detecting unit 60 or the environmental temperature detected by the temperature detecting unit 90. Of course, as in the second embodiment, the adjusting unit 55 may adjust the driving condition of the suction device 42 according to the environmental temperature input by the user or the environmental air temperature.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, of course, this invention is not limited to the said embodiment. In the above-described embodiment, for example, based on the tables shown in Tables 1 and 2, the driving conditions of the suction device according to the ambient pressure and the ambient temperature are set. The driving condition of the suction device may be set according to the ambient atmospheric pressure or the like based on a predetermined calculation formula.

  In the above-described embodiment, the electrostatic drive type recording head is exemplified as the ink jet type recording head. However, in the configuration of Embodiments 1, 2, or 4, the driving method of the ink jet type recording head is particularly limited. It is not something.

  Furthermore, in the above-described embodiment, the present invention has been described with reference to an ink jet recording apparatus including an ink jet recording head as an example of the liquid ejecting apparatus. However, the present invention is widely intended for all liquid ejecting apparatuses. Of course, the present invention can also be applied to a liquid ejecting apparatus including a liquid ejecting head that ejects liquid other than ink. Specifically, for example, various recording heads used in image recording apparatuses such as printers, color material ejection heads used in the manufacture of color filters such as liquid crystal displays, electrodes such as organic EL displays and FEDs (surface emitting displays) Examples thereof include a liquid ejecting apparatus including an electrode material ejecting head used for forming, a bioorganic matter ejecting head used for biochip production, and the like.

1 is a schematic perspective view of a recording apparatus according to Embodiment 1. FIG. 2 is a schematic perspective view of a recording head according to Embodiment 1. FIG. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment. 1 is a schematic diagram of a cleaning device according to Embodiment 1. FIG. 1 is a schematic plan view of a suction device according to Embodiment 1. FIG. FIG. 2 is a functional block diagram of the recording apparatus according to the first embodiment. It is a graph which shows the relationship between environmental atmospheric pressure and ink consumption. 6 is a functional block diagram of a recording apparatus according to Embodiment 2. FIG. FIG. 6 is a functional block diagram of a recording apparatus according to a third embodiment. It is a figure which shows the deformation | transformation state resulting from the environmental pressure of a diaphragm. FIG. 6 is a functional block diagram of a recording apparatus according to a fourth embodiment. It is a graph which shows the relationship between environmental temperature and ink consumption.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording device, 2 Head unit, 3 Ink cartridge, 4 Carriage, 5 Apparatus main body, 6 Carriage shaft, 7 Drive motor, 8 Timing belt, 9 Platen, 10 Recording head, 11 Cavity substrate, 12 Pressure chamber, 13 Common ink chamber , 14 ink supply hole, 15 through hole, 16 diaphragm, 17 common terminal portion, 20 nozzle plate, 21 nozzle, 22 nozzle stepped portion, 23 ink supply path, 24 exposed hole, 25 liquid repellent film, 30 electrode substrate, 31 Groove, 32 Ink introduction hole, 33 Individual electrode, 34 Individual terminal section, 35 Lead electrode, 40 Cleaning device, 42 Suction device

Claims (11)

  A head unit having a liquid flow path including a pressure chamber communicating with the nozzle and having a liquid ejecting head for applying a pressure to the liquid in the pressure chamber and discharging droplets from the nozzle; and a predetermined amount in the pressure chamber from the nozzle A suction means for performing a suction operation for sucking with the suction force of the pressure chamber and discharging the liquid in the pressure chamber, and an adjustment means for adjusting the suction force by the suction means in accordance with at least the ambient atmospheric pressure at the place of use. A liquid ejecting apparatus.   The air pressure detecting means for detecting the atmospheric pressure of a use environment is further provided, and the adjusting means adjusts the suction force of the suction means according to the environmental air pressure detected by the air pressure detecting means. The liquid ejecting apparatus according to 1.   An input means for inputting the altitude of the use environment; and an atmospheric pressure calculating means for calculating the environmental atmospheric pressure from the altitude input by the input means; and the adjusting means adjusts the environmental atmospheric pressure calculated by the atmospheric pressure calculating means. The liquid ejecting apparatus according to claim 1, wherein the suction force by the suction unit is adjusted accordingly.   The liquid ejecting head applies a driving voltage pulse between a flexible electrode provided on one surface of the pressure chamber and a fixed electrode disposed to face the flexible electrode at a predetermined interval, An actuator that vibrates the flexible electrode by electrostatic force generated therebetween, and further includes an air pressure calculating unit that calculates an environmental air pressure from a capacitance of the actuator, and the adjusting unit includes The liquid ejecting apparatus according to claim 1, wherein the suction force by the suction unit is adjusted according to an ambient pressure calculated by the atmospheric pressure calculation unit.   The liquid ejecting head applies a driving voltage pulse between a flexible electrode provided on one surface of the pressure chamber and a fixed electrode disposed to face the flexible electrode at a predetermined interval, An actuator that vibrates the flexible electrode by electrostatic force generated therebetween, and further includes an atmospheric pressure calculating unit that calculates an atmospheric pressure from a residual vibration waveform of the flexible electrode, and the adjusting unit 2. The liquid ejecting apparatus according to claim 1, wherein the suction force by the suction unit is adjusted according to an ambient pressure calculated by the atmospheric pressure calculation unit.   In the range of the environmental temperature at which the pressure chamber is sucked at a constant pressure when the adjusting means performs the suction operation, the suction force by the suction means is adjusted according to the ambient atmospheric pressure at the place of use, and the suction operation is performed. 6. The suction force by the suction means is adjusted in accordance with the environmental temperature of the place of use in a range of environmental temperature at which the pressure chamber is suctioned in a fixed amount when executed. The liquid ejecting apparatus described.   The temperature detecting means for detecting the environmental temperature of the place of use is further provided, and the adjusting means adjusts the suction force of the suction means according to the environmental temperature of the place of use detected by the temperature detecting means together with the ambient atmospheric pressure of the place of use. The liquid ejecting apparatus according to claim 6, wherein the liquid ejecting apparatus is adjusted.   The liquid ejecting apparatus according to claim 1, wherein the adjustment of the suction force of the suction unit is adjustment of a suction speed by the suction unit.   9. The liquid jet according to claim 8, wherein the suction means sucks the pressure chamber by a tube pump, and the adjustment of the suction force of the suction means is adjustment of the rotation speed of the tube pump. apparatus.   The liquid ejecting apparatus according to claim 8, wherein the adjustment of the suction force of the suction unit is adjustment of a suction time by the suction unit in one suction operation. The suction means sucks the pressure chamber by a tube pump, and the adjustment of the suction force of the suction means is adjustment of the number of rotations of the tube pump in one suction operation. Item 11. The liquid ejecting apparatus according to Item 10.

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