JP2019098592A - Inkjet recording device - Google Patents

Abstract

To provide an inkjet recording device that can counter influence on discharged ink droplets of gas flow of air for adsorbing a recording medium which is used in a conveying mechanism for a recording medium, and a recording method.SOLUTION: An inkjet recording device comprises: a conveyance belt having a plurality of suction holes for suctioning a recording medium to be placed on the belt; a recording head which is arranged to oppose to the conveyance belt, discharges ink through a discharge port to the recording medium suctioned by the suction holes and conveyed; and control means that changes speed at which ink is discharged through the discharge port depending on margin amounts in a range from a tip of the recording medium to be conveyed to a region where recording is performed by discharging the ink.SELECTED DRAWING: Figure 7

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an inkjet recording apparatus which ejects ink onto a recording medium to record.

  In Patent Document 1, a conveyance mechanism is provided that has a suction hole for suctioning air in the conveyance belt, and suctions air through the suction hole to move the recording medium to be conveyed in a state where the recording medium to be conveyed is adsorbed to the conveyance belt. Have been described. According to this transport mechanism, the recording medium can be reliably transported in synchronization with the transporting transport belt.

JP, 2010-37001, A

  However, when the transport mechanism of Patent Document 1 is used in an inkjet recording apparatus that ejects ink onto a recording medium, there is a possibility that the impact position of the ink ejected from the recording head may be shifted due to the air flow generated due to suction. There is. That is, when suctioning the recording medium onto the belt, among the suction holes provided in the belt, suction holes that are not covered by the recording medium exist according to the belt loading position of the recording medium. When the discharge position of the recording head relative to the recording medium is close to the suction hole not covered by the recording medium, the air flow passing through the suction hole changes the flying direction of the ink droplet discharged at the discharge position, and as a result, The ink landing position of may be shifted.

  Therefore, an object of the present invention is to provide an ink jet recording apparatus capable of suppressing the influence on the discharged ink droplets by the air flow of the recording medium suction air used for the conveyance mechanism of the recording medium.

  A transport belt having a plurality of suction holes for sucking the recording medium to be placed, and a recording head disposed opposite to the transport belt and discharging ink from the discharge port to the recording medium which is adsorbed by the suction holes and transported. And control means for changing the ink discharge speed discharged from the discharge port according to the margin amount from the leading end of the recording medium to be discharged to the area for discharging and recording the ink.

  According to the present invention, it is possible to suppress the deterioration of the image quality due to the flow of suction air for transporting the recording medium.

FIG. 1 is a schematic configuration view of an ink jet recording apparatus according to a first embodiment of the present invention. It is a block diagram which shows the structure of the control system of the inkjet recording device shown in FIG. FIG. 2 is a view partially showing a mechanism for mainly transporting a recording medium in the ink jet printing apparatus according to the first embodiment. FIG. 6 is a view for explaining the influence of an air flow generated when a suction fan sucks a recording medium on discharged droplets. It is the image which saw the ink impact position of FIG. 4 from the upper surface. FIG. 7 is a table showing the relationship between the margin amount at the leading edge of the continuous sheet and the number of preliminary discharges (pre-discharge number) to be executed before recording. It is a flowchart which shows the process to the recording operation including the preliminary | backup discharge performed before the recording operation which concerns on 1st Embodiment of this invention. FIG. 7 is a view showing a positional relationship among ink droplets ejected from the recording head in the second embodiment, continuous paper, and suction holes of a conveyance belt. It is the figure which looked at the conveyance unit in the ink jet recording device concerning a 2nd embodiment of the present invention from the upper part. FIG. 8 is a view showing a table for determining the distance between the suction hole and the recording start position and the number of preliminary discharges before recording. FIG. 7 is a table showing the relationship between the margin amount at the leading end of the continuous sheet and the heating temperature to be executed before recording. It is a flowchart which shows the process regarding recording head heating performed before the recording operation which concerns on 3rd Embodiment of this invention. It is a figure which shows the table for determining the distance of a suction hole and a recording start position, and heating temperature.

  Hereinafter, embodiments of the present invention will be described in detail.

First Embodiment
FIG. 1 is a schematic block diagram of the ink jet recording apparatus according to the first embodiment of the present invention. An inkjet recording apparatus 100 (hereinafter, also simply referred to as a recording apparatus) is connected to a host computer 101 as an information processing apparatus. The host computer 101 outputs image data, a cut position of the recording medium, information on the recording medium, and the like to the recording apparatus 100 as a control command via the printer cable 102. The continuous paper 103, which is a recording medium wound into a roll, is cut after an image is recorded, as described later. The conveyance unit 104, which is a conveyance unit of the continuous paper 103, includes a conveyance motor 105, a conveyance belt 106, and a suction fan 107. The transport belt 106 is bridged between the guide rollers 108A, 108B, 108C and the drive roller 108D. The drive roller 108D is rotated by the transport motor 105 capable of forward and reverse rotation, and the transport belt 106 for loading and transporting the continuous paper 103 is moved in the arrow A1 direction or the reverse arrow A2 direction. By rotating the suction fan 107 as suction means, air is sucked from the suction holes 116 (see FIG. 4 etc.) formed in plural on the conveyance belt 106 and discharged from the exhaust port 109 of the conveyance unit 104. The transport belt 106 can transport the continuous paper 103 in the directions of arrows A1 and A2 while adsorbing the continuous paper 103 to the surface of the transport belt 106 by suction of air from the suction holes 116.

  In the recording unit 110, a plurality of recording heads 110H (see FIG. 4) capable of recording an image on the continuous paper 103 are detachably mounted opposite to the conveyance belt. The recording head 110H can discharge ink using an electrothermal transducer (heater) as a discharge energy generating element. The electrothermal transducer can foam the ink by the heat generation, and can eject the ink from the ejection port at the tip of the nozzle formed in the recording head using the foaming energy. In this embodiment, as the recording head 110H, a recording head for discharging black (K), cyan (C), magenta (M), and yellow (Y) inks in order to perform full-color printing on the continuous paper 103 110 K, 110 C, 110 M, and 110 Y are provided. These are disposed along the sheet conveyance directions A1 and A2. Note that the number of colors, that is, the number of recording heads can be arbitrarily determined, and hereinafter, it will be comprehensively referred to simply as “recording head 110H”.

  Such a recording apparatus 100 has a preliminary ejection operation, a pressure recovery operation, a suction recovery operation, a wiping operation, and the like as recovery processing related to ink ejection. In the recording unit 110 of the present embodiment, a cap unit (not shown) for receiving the ink ejected by the preliminary ejection operation performed prior to the printing operation is disposed. The recording apparatus 100 includes a leading edge detection sensor 111 that detects the leading edge of the continuous paper 103 in order to obtain recording timing, and a leading edge detection sensor 112 that detects the leading edge of the continuous paper 103 in order to obtain cutting timing of the continuous paper 103 It is done. In the case where the continuous paper 103 is a sheet to be recorded and cut for each predetermined unit area, and is a sheet to which a mark capable of detecting the unit area is attached, the mark is used to The tip can be detected. The leading end detection sensors 111 and 112 are configured to include either or both of a reflection type sensor and a transmission type sensor. For example, when the continuous sheet 103 is a label sheet, the front end of the label as a unit area is detected by the difference in transmittance between the backing sheet and the label attached to the backing sheet. Also, in the case of a sheet with a detection mark, the leading edge of the page as a unit area is detected by the difference in light reflectance between the sheet and the mark.

  The rotation shaft of the guide roller 108A is provided with an encoder (not shown) that rotates in synchronization with the rotation shaft, which is detection means for detecting the conveyance position of the continuous paper 103. The conveyance of the continuous paper 103 by the conveyance unit 104, the recording timing by the recording unit 110, and the cutting timing by the cutting unit 113 described later are controlled by the CPU 201 of the control unit 200 described later based on the detection signal of the encoder.

  The cutter as the cutting portion 113 includes a rotary blade 113A, a fixed blade 113B, and a stopper 113C, and the stopper 113C is released (moved upward in the figure) by a solenoid (not shown). By the release of the stopper 113C, the rotary blade 113A rotates in the direction of arrow D, and the continuous paper 103 is cut by the rotary blade 113A and the fixed blade 113B. When the continuous paper 103 is conveyed by the conveyance unit 104 in the direction of the arrow A1, the continuous paper 103 is cut at the timing when the cutting position (not shown) on the continuous paper 103 reaches the fixed blade 113B.

  FIG. 2 is a block diagram showing the configuration of a control system of the ink jet printing apparatus shown in FIG. The control unit 200 of the recording apparatus 100 includes a central processing unit (CPU) 201, and the CPU 201 executes a control program such as a program described later in FIG. 7 and the like stored in the non-volatile memory (ROM) 202. , Control each component of the recording apparatus 100. The control unit 200 also includes a memory (RAM) 203 used as a work area for various data processing and a reception buffer, and an image memory 204 as an image developing unit.

  The control circuit 210 of the control unit 200 includes a recording head drive circuit 205 for driving the recording head 110H, a motor driver 207, a sensor 208, and the like. The motor driver 207 is a driver for various motors 206 that drive the cleaning operation, recording operation, and cutting operation of the recording head 110H. A sensor 208 is a sensor used for control of various operations in the recording apparatus 100, detection of the continuous paper 103, and the like. The control unit 200 is connected to the host computer 101 through the USB 209.

  A recording command transmitted from the host computer 101 of the present embodiment to the recording apparatus 100 via the printer cable 102 will be described. The recording command includes a recording medium setting command for notifying the recording medium size and the like, a format command for specifying the recording area and the like, a conveyance speed setting command for specifying the conveyance speed of the recording medium, and data for notifying the image data of the recording image. There is a command. Further, the recording command includes a cut designation command for specifying the presence or absence of the cutting on the continuous paper 103 and the cutting position. The control regarding the pre-recording process described later is performed based on the margin amount (tip margin amount) of the data command.

  When the cutting interval is set to 1 or more, the cutting unit 113 cuts the continuous paper 103 by the cut designation command under the control of the CPU 201. The cutting interval indicates the interval at which cutting is performed. When the cutting interval is set to 1, continuous paper is cut for each recording medium longitudinal size (unit area). For example, when a plurality of recording sheets are designated and the cutting interval is set to a plurality of two or more, continuous paper is provided for each area obtained by integrating the number set as the cutting interval and the recording medium longitudinal size. Is cut off.

  For example, in the case where so-called copy recording is performed when the number of sheets to be recorded is two or more, it is assumed that the cutting interval is set to 2 and the vertical size of the recording medium is set to 40 mm. In this case, the cut length of the continuous paper 103 is 80 mm (= 2 × 40 mm) which is the product of the cutting interval 2 and the recording medium longitudinal size 40 mm. Thus, the continuous paper 103 is cut every 80 mm. In addition, regardless of the number of recording sheets, when the cutting interval is 1, the cutting length is set to 40 mm (1 × 40 mm), and the continuous paper 103 is cut every 40 mm of the recording medium vertical size (unit area).

  The drawing color command stores the number of drawing colors, and the image data command stores one or more data according to the number of drawing colors. When the drawing color is only K (black), one image data is stored, and when the drawing color is K (black), C (cyan), M (magenta) or Y (yellow), Four image data are stored in order.

  FIG. 3 is a schematic view partially showing a mechanism for transporting a recording medium in the ink jet printing apparatus according to the first embodiment. When the suction fan 107 sucks air via the suction holes 116 (see FIG. 4 etc.) provided in the conveyance belt 106, the continuous paper 103 in the portion covering the suction holes 116 is attracted to the surface of the conveyance belt 106 It is pressed. Then, in a state where the continuous paper 103 is adsorbed to the conveyance belt 106, the conveyance belt 106 is moved (traveled), whereby conveyance of the continuous paper 103 in the direction of arrow A1 is performed. When the continuous sheet 103 is a label sheet, the continuous sheet 103 is not shown, which rotates in synchronization with the rotation axis of the guide roller 108A after the leading edge of the label passes under the leading edge detection sensor 111 and is detected. The transport position of the label sheet is detected by At the time of recording operation, ink is ejected from the recording head 110H of the recording unit 110 while the continuous sheet 103 is continuously conveyed in the direction of the arrow A1, so that one page P1, two pages P2,. The images 115 (1), 115 (2),...

  FIGS. 4A and 4B are schematic diagrams for explaining the influence of the air flow generated by the suction fan at the time of suction of the recording medium on the discharged droplets, and ink droplets discharged from the recording head 110H, the continuous paper 103, and the conveyance belt The positional relationship of the 106 suction holes is shown. FIG. 4A shows a state after the continuous paper 103 has been conveyed and the leading edge of the continuous paper 103 has passed the entire recording head 110H. At this time, suction by the suction fan 107 is performed, and an air flow passing through the suction holes 116 not covered by the continuous paper 103 is generated. In the state shown in FIG. 4A, the position of the suction hole 116 where the leading edge of the continuous paper 103 passes through the recording head 110H and the continuous paper 103 does not cover is relatively far from the position where the recording head 110H discharges ink. It is a state. As a result, there is almost no influence from the air flow of the ejected ink droplets passing through the suction holes 116, and the landing position of the ejected ink does not shift. FIG. 5A is a top view of the recording surface of the continuous paper 103 at this time. As shown in the figure, it can be seen that the ink droplet lands on the position where the straight line (the ruled line) 50 which is an image recorded by the discharged ink is to be recorded, and the straight line 50 is formed.

  On the other hand, FIG. 4B shows a state in which the leading end of the continuous paper 103 passes the discharge position of the recording head 110H. At this time, as in the state shown in FIG. 4A, suction by the suction fan 107 is performed, and an air flow passing through the suction holes 116 not covered by the continuous paper 103 is generated. However, in the state shown in FIG. 4B, the leading end of the continuous paper 103 has passed the discharge position of the recording head 110H and the time has not passed so much, and the position of the suction hole 116 which the continuous paper 103 does not cover is The recording head 110H is relatively close to the position where the ink is ejected. In this case, the ejected ink droplet is affected by the air flow passing through the nearby suction hole 116, and the flying direction of the ejected ink changes, resulting in the deviation of the landing position. FIG. 5B is a top view of the recording surface of the continuous paper 103 at this time. As shown in the figure, the ink ejected from the recording head 110 H is scattered and lands toward the leading end of the continuous paper 103 rather than the position where the straight line 50 which is the target landing position is recorded. ).

  When the distance between the discharge position of the recording head 110H and the suction hole 116 of the conveyance belt 106 not covered by the continuous paper 103 becomes short as described above, the landing position of the ink is shifted. In the present embodiment, the position of the suction hole 116 of the transport belt 106 not covered by the continuous paper 103 is unknown. Therefore, if the suction holes 116 exist at the front end position, the smaller the margin amount of the front end, which is the distance from the front end of the continuous paper 103 to the recording start position where the ink is discharged first, There is a possibility that the landing position of the ink may be shifted. Therefore, in the present embodiment, the means for coping with the air flow is changed according to the front end margin amount of the continuous paper 103.

  One embodiment of the present invention addresses the influence of air flow caused by suction described above with reference to FIGS. 4B and 5B by increasing the discharge speed of the ink discharged from the recording head 110H. Specifically, the viscosity of the ink decreases as the tip margin amount decreases. As a result, the viscosity resistance due to the discharge port, the liquid passage, and the like in the recording head 110H can be reduced, and the discharge speed of the ink can be increased. As a result, even if the air pressure is generated in the ink droplet ejected and flying by the air flow, the deviation of the landing position can be reduced. In the present embodiment, the temperature of the ink in the discharge port is raised by increasing the number of discharges of the preliminary discharge performed before recording. As a result, the viscosity of the ink is reduced and the discharge speed is increased. Then, in the present embodiment, the number of ejections of the above-described preliminary ejection is determined according to the front end margin amount of the recording medium in which the distance from the front end changes according to the image data.

  FIG. 6 is a table showing the relationship between the margin amount at the leading edge of the continuous paper and the number of preliminary discharges (pre-discharge number) to be executed before recording, and this table is stored in the ROM 202 of the control unit 200. It is done. In the present embodiment, even if the preliminary ejection number is located at the closest distance between the leading edge of the continuous paper 103 and the suction hole 116 not covered by the continuous paper 103 of the conveyance belt 106, the leading edge margin amount The ink ejection speed is set to be a sufficient value in accordance with the above. In addition, as the front end margin amount decreases, the number of preliminary discharges is increased. This is because the suction hole 116 and the landing position of the discharged ink come closer to each other as the tip margin amount becomes smaller, and the influence of the air flow from the suction hole 116 is more likely. Therefore, the discharge speed is increased by increasing the temperature of the ink in the discharge nozzle and decreasing the viscosity of the ink by increasing the preliminary discharge number as the tip margin amount decreases. Thereby, even if the front end margin amount is small, the deviation of the landing position of the discharged ink is reduced according to the influence of the air flow due to the suction. On the other hand, when it is difficult to receive the influence of the air flow from the suction holes 116 (when the tip margin amount is large), setting the preliminary ejection number small reduces the deviation of the landing position, and discards the ink to be discarded by the preliminary ejection. Consumption can be minimized.

  FIG. 7 is a flow chart showing processing relating to predischarge performed before the recording operation according to the first embodiment of the present invention. When the recording apparatus 100 receives a recording command including a recording command from the host computer 101, the CPU 201 of the control unit 200 starts processing before the recording operation. First, the tip margin amount is determined based on the data command (S601). Then, with reference to the pre-recording preliminary ejection table shown in FIG. 6 stored in the ROM 202 of the control unit 200, the number of pre-recording preliminary ejections corresponding to the tip margin amount determined in step S601 is determined (S602). Thereafter, in order to stabilize the preliminary ejection, heating of the ink in the recording head 110H is started to be a constant temperature (30 ° C.) (S603). Whether or not the ink temperature in the recording head 110H has reached a constant temperature is determined according to the detection of the in-head temperature sensor 211 (see FIG. 2) in the flow path of the recording head 110H (S604). If the ink temperature has not reached a constant temperature, heating is continued until the constant temperature is reached (S604 NO). Then, when the constant temperature is reached (S604 YES), the heating in the recording head 110H is ended (S605), and the preliminary ejection is started until the number of preliminary ejections determined in step S602 is reached (S606). When the preliminary ejection number is reached (S607 YES), the preliminary ejection is ended (S608). The motor 206 is driven by the motor driver 207 to move the recording head 110H to the recording position (S609), the processing before the recording operation is ended, and the process shifts to the recording operation (S610).

  As described above, according to the present embodiment, the number of predischarges before recording is changed according to the tip margin amount. By this preliminary discharge, the discharge port and the ink in the inside thereof are heated, and the viscosity of the ink is reduced, whereby the discharge speed of the ink is increased. As a result, it is possible to suppress the deviation of the landing position of the ink due to the air flow flowing through the suction holes of the transport belt due to the suction operation of the transport unit.

  Note that the recording unit 110 in the present embodiment is configured to use a full line type ink jet recording head. However, the recording unit 110 is not such a full line method, but is a serial scan method in which an image is recorded along with scanning of the recording head in the main scanning direction and conveyance of the continuous paper 103 in the sub scanning direction. It is also good. Further, the number of nozzle rows in the recording head 110H is not limited to one, and a plurality of nozzle rows may be formed in parallel. Furthermore, the color of the ink used for recording an image is not limited to only one color, and may be a plurality of colors.

  Further, in the present embodiment, the relationship between the front end margin amount and the number of preliminary discharges before recording is as shown in FIG. However, if the number of preliminary discharges can be set so that the discharge speed of the ink becomes a sufficient value even when the leading edge of the continuous paper 103 and the suction holes 116 are positioned at the closest distance, FIG. It does not have to be limited to the number of preliminary discharges shown in FIG. Furthermore, the relationship between the tip margin amount and the preliminary ejection number is not a table that has been set and stored in advance, as described above, but the ink ejection speed is calculated by multiplying the tip margin amount obtained by a predetermined coefficient. The number of predischarges required to increase the number may be calculated.

  In the present embodiment, the influence on the ink discharge of the air flow passing through the suction holes not covered by the recording medium at the leading end side of the recording medium is suppressed, but the suction holes are also on the trailing end side of the conveyed recording medium. Exists. However, when forming an image, the ink discharge port of the recording head discharges ink continuously toward the conveyed continuous paper 103 in order to record an image from the front end side of the recording medium. For this reason, the electrothermal transducer (heater) as a discharge energy generating element is continuously driven, and the ink viscosity is lowered by the increase in the ink temperature due to the continuous driving of the element. For this reason, since the ink discharge speed also increases, the air flow passing through the suction holes present on the rear end side of the recording medium can have negligible influence on the ink discharge. In addition, there is a transport mechanism in which a suction hole which does not cover the recording medium exists on the recording medium end side in the width direction orthogonal to the transport direction of the recording medium. In this case, the ink discharge port positioned on the recording medium end side in the width direction of the recording medium is also affected by the air flow of the suction hole in the recording near the front end because the image is recorded from the front end side of the recording medium. However, the ink discharge near the front end can be dealt with according to the present embodiment, and the ink discharge port of the recording head discharges the ink continuously toward the continuous paper 103 being conveyed. For this reason, the ink discharge port on the end side is also positioned at the recording medium end side because the ink viscosity decreases and the ink discharge speed also increases due to the ink temperature rise due to the continuous drive of the electrothermal transducer (heater). The effect of air flow through the suction holes can be ignored.

Second Embodiment
The basic configuration of the present embodiment is the same as that of the first embodiment, so only the characteristic configuration of the present embodiment will be described below. In the first embodiment, the preliminary ejection number is set based on a table provided on the assumption that the leading edge of the continuous paper 103 and the suction hole 116 are located at the closest distance. However, in the present embodiment, the distance between the suction hole 116 and the recording start position is detected more accurately by finding the distance between the suction hole 116 and the leading edge of the continuous paper 103 on the conveyance belt 106, and the ink discharge speed is calculated. It is possible to set the number of predischarges necessary to increase the number.

  FIG. 8 is a schematic view showing the positional relationship among ink droplets ejected from the recording head 110H in the second embodiment, the continuous paper 103, and the suction holes of the conveyance belt 106. FIG. 9 is a schematic view of the transport unit in the ink jet recording apparatus according to the second embodiment of the present invention as viewed from above. The continuous paper 103 is conveyed by the conveyance belt 106 in a state of being adsorbed by suction holes 116 provided in the conveyance belt 106. And in the conveyance belt 106 in the second embodiment, a reference concave portion 117 is provided at a position detected by the leading end detection sensor 111. The distance from the reference recess 117 to each suction hole 116 is predetermined. By detecting the reference concave portion 117 and the leading end of the continuous paper 103 by the leading end detection sensor 111, the CPU 201 of the control unit 200 determines the position (position B) of the suction hole 116 closest to the leading end of the continuous paper 103. Specifically, the position B is not covered by the continuous paper 103 in the suction holes 116 of the transport belt 106, is closer to the cutting portion 113 than the front end of the continuous paper 103, and is the shortest with the front end of the continuous paper 103. Located at a distance. Next, the distance to the suction hole 116 (B) that has passed the leading edge detection sensor 111 before the leading edge of the continuous paper 103, which is closest to the recording start position G of the leading edge of the recording area The (distance between BG) is calculated by the CPU 201. Then, based on the calculated BG distance, the number of ejections of the preliminary ejection before recording is set.

  FIG. 10 is a diagram showing a table for determining the distance between the suction hole (B) and the recording start position (G) (distance between BG) and the number of preliminary discharges before recording, which is stored in the ROM 202 of the control unit 200 There is. As in the first embodiment, in the flowchart of FIG. 7, after the recording apparatus 100 receives a recording command including a recording command from the host computer 101, the processing before the recording operation is started. First, the pre-recording preliminary ejection table shown in FIG. 10 is referred to according to the above-described BG distance, and the pre-recording preliminary ejection number is determined. Next, after heating to a constant temperature (30 ° C.), predischarge before recording is performed. After that, it shifts to the recording operation.

  As described above, in the second embodiment, the preliminary ejection number before recording is changed according to the above-described BG distance. By this, the ink inside the recording head is heated, and the discharge speed is increased by lowering the viscosity of the ink, so that the deviation of the landing position of the ink due to the air flow generated by the suction holes of the transport belt not covered by the continuous paper is suppressed. can do. Further, when the influence of the air flow from the suction hole 116 is not easily received (when the distance between BGs is large), by setting the preliminary ejection number small, the deviation of the landing position is reduced and the ink to be discarded by the preliminary ejection is used. Consumption can be reduced. Note that the relationship between the BG distance and the number of preliminary discharges is not a table that has been set and stored in advance, as described above, but in order to increase the ink discharge speed by multiplying the BG distance by a predetermined coefficient A necessary number of preliminary discharges may be calculated.

Third Embodiment
The basic configuration of the present embodiment is the same as that of the first embodiment, so only the characteristic configuration of the present embodiment will be described below. In the first embodiment, the electrothermal transducer (heater) is used as the discharge energy generating element of the recording head 110H, but in the present embodiment, a mechanical energy generating element such as a piezo element is used as the discharge energy generating element. May be

  In this embodiment, an in-head temperature sensor 211 (see FIG. 2) provided in the ink flow path of the recording head 110H via the recording head drive circuit 205 instead of determining the pre-recording preliminary ejection number in the first embodiment. ) To control the ink temperature. Then, while controlling the ink temperature by the in-head temperature sensor 211, the heater for heating in the recording head is driven to heat the ink and reduce the viscosity of the ink. As a result, the ink ejected from the recording head 110 H reduces the deviation of the landing position against the influence of the air flow generated by the suction holes 116.

  FIG. 11 is a diagram showing a table for determining the relationship between the margin amount (tip margin amount) at the leading end of continuous paper and the heating temperature to be executed before recording, and this table is stored in the ROM 202 of the control unit 200.

  FIG. 12 is a flowchart showing a process related to print head heating which is performed before a print operation according to the third embodiment of the present invention. When the recording apparatus 100 receives a recording command including a recording command from the host computer 101, the CPU 201 of the control unit 200 starts processing before the recording operation. First, as in the first embodiment, the front end margin amount is determined based on the data command (S1201). Then, with reference to the recording head heating temperature table shown in FIG. 11, the recording head heating temperature corresponding to the tip margin amount determined in step S1201 is determined (S1202). Thereafter, after the recording head heating temperature is determined, the heating of the recording head 110H is started (S1203). Then, it is determined whether the temperature in the recording head 110H has reached the temperature determined by the in-head temperature sensor 211 (see FIG. 2) of the recording head 110H and determined in step S1202 (S1204). Heating is continued until the ink temperature reaches the determined temperature. Then, when the heating temperature is reached (S1204 YES), preliminary discharge is performed (S1205). Then, when the preliminary ejection operation is completed, the motor 206 is driven by the motor driver 207 to move the recording head 110H to the recording position (S1206), shift to the recording operation (S1207), and end the processing.

  The relationship between the tip margin amount and the heating temperature is not a table that is set and stored in advance as described above, but the ink is obtained by multiplying the tip margin amount determined by image data by a predetermined coefficient. The heating temperature required to increase the discharge speed may be calculated.

  Further, in the present embodiment, a heater dedicated to heating is used to heat the ink in the recording head. However, when an electrothermal transducer (heater) is used as a discharge energy generating element of the recording head as in the first embodiment, the heater driving time for discharge is adjusted without providing a heater dedicated to heating. The ink in the recording head may be heated without discharging the ink.

Fourth Embodiment
The basic configuration of the present embodiment is the same as that of the second embodiment, so only the characteristic configuration of the present embodiment will be described below. In the second embodiment, the electrothermal transducer (heater) is used as the discharge energy generating element of the recording head 110H, but in the present embodiment, a mechanical energy generating element such as a piezo element is used as the discharge energy generating element. May be

  FIG. 13 is a diagram showing a table for determining the distance (the distance between BG) between the suction hole (B) and the recording start position (G) and the heating temperature, and is stored in the ROM 202 of the control unit 200. Instead of determining the pre-recording preliminary ejection number in the second embodiment, an in-head temperature sensor 211 (shown in FIG. 1) is provided in the flow path of the recording head 110H via the recording head drive circuit 205 according to the obtained inter-BG distance. Adjust the temperature by 2). Then, the viscosity of the ink is reduced by driving the heater for heating while adjusting the temperature by the in-head temperature sensor 211.

  As in the third embodiment, in the flowchart of FIG. 12, after receiving the recording command including the recording command from the host computer 101, the recording apparatus 100 starts the pre-processing of the recording operation. The print head heating temperature is determined with reference to the print head heating temperature table shown in FIG. 13 according to the margin amount (tip margin amount) of the print medium setting command. After the recording head heating temperature is determined, the recording head is heated. Then, after detecting by the in-head temperature sensor 211 that the temperature of the recording head has risen to the determined temperature, preliminary discharge before recording is performed, and the process shifts to the recording operation. During this time, the heater for heating is driven to maintain the determined temperature, and the heating of the head is ended after the shift to the recording operation.

  The relationship between the BG distance and the heating temperature is not a table that has been set and stored in advance, as described above, but the ink discharge speed is increased by multiplying the calculated BG distance by a predetermined coefficient. You may calculate the heating temperature required for.

  Further, in the present embodiment, a heater dedicated to heating is used to heat the ink in the recording head. However, when using the electrothermal transducer (heater) as the discharge energy generating element of the recording head as in the second embodiment, the heater driving time for discharge is adjusted without providing a heater dedicated to heating. The ink in the recording head may be heated without discharging the ink.

(Other embodiments)
The continuous paper is not limited to a roll only, and may be, for example, a recording medium folded in a bellows shape, a straight continuous recording medium, or a recording medium cut into sheets. The cutting unit 113 is not limited to the configuration using the rotary blade 113A, and may be, for example, a cutter that cuts continuous paper in a sliding manner.

  Further, the conveyance unit 104 as a conveyance means only needs to be able to suction and convey a continuous recording medium, and is not necessarily specified only in the configuration in which the recording medium is adsorbed to the conveyance belt 106 and conveyed. For example, the recording medium may be conveyed on the conveyance surface while the recording medium is suctioned to the conveyance surface.

Reference Signs List 100 inkjet recording apparatus 101 host computer 106 conveyance belt 107 suction fan 110 H recording head 111 leading edge detection sensor 116 suction hole 117 reference concave portion

Claims (7)

A transport belt having a plurality of suction holes for sucking the recording medium to be placed;
A recording head which is disposed to face the conveyance belt and discharges ink from a discharge port to a recording medium which is adsorbed and conveyed by the suction hole;
An ink jet recording apparatus characterized by further comprising: control means for changing an ink discharge speed discharged from the discharge port in accordance with a margin amount from a leading end of a recording medium to be conveyed to a region where the ink is discharged and recorded. .   The inkjet recording apparatus according to claim 1, wherein the control unit changes the ink discharge speed by changing the temperature of the ink in the recording head.   3. The inkjet recording apparatus according to claim 2, wherein the control unit changes the temperature of the ink in the recording head by changing the number of preliminary discharges executed before recording.   3. The ink jet printing apparatus according to claim 2, wherein the control unit changes the temperature of the ink in the print head by controlling a heater in the print head.   The ink jet recording apparatus according to claim 2, wherein the temperature of the ink to be changed becomes higher as the margin amount becomes smaller.   The inkjet recording apparatus according to claim 3, wherein the preliminary ejection number increases as the margin amount decreases.   2. The apparatus according to claim 1, wherein the control means changes the ink discharge speed in accordance with an amount obtained by adding the distance from the leading edge of the recording medium to the suction hole positioned upstream in the transport direction to the margin amount. The inkjet recording device according to any one of 6.