EP3489018A1

EP3489018A1 - Ink jet recording apparatus and method for controlling ink jet recording apparatus

Info

Publication number: EP3489018A1
Application number: EP17830679.1A
Authority: EP
Inventors: Naoya Komada
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 2016-07-21
Filing date: 2017-05-16
Publication date: 2019-05-29
Also published as: JP6922912B2; JPWO2018016159A1; EP3489018A4; WO2018016159A1

Abstract

Provided are an ink jet recording apparatus and a method for controlling an ink jet recording apparatus by which adjustment ejection of ink can be performed on a recording medium regardless of the content of a normal image, while suppressing wasteful consumption of the recording medium. The ink jet recording apparatus is provided with: an ink ejection unit having a nozzle for ejecting ink; ejection control means for causing the ink ejection unit to perform adjustment ejection of the ink from the nozzle according to at least one of adjustment and examination of an ink ejection operation from the nozzle onto a recording medium; and detection means for detecting a property difference part representing a local part of the recording medium and having a property different from a property of a part other than the local part. The ejection control means causes the ink ejection unit to perform the adjustment ejection from the nozzle within a range of an adjustment ejection region on the recording medium including at least some of the property difference part detected by the detection means.

Description

TECHNOLOGICAL FIELD

The present invention relates to an ink jet recording apparatus and a method for controlling an ink jet recording apparatus.

BACKGROUND ART

There have been inkjet recording apparatuses which discharge ink onto a recording medium from ink discharger with nozzles from which ink is discharged to record an image(s) on the recording medium. In the inkjet recording apparatuses, there is a problem that, when ink not yet discharged is exposed to air at an opening of nozzle, the characteristics of ink is altered due to the evaporation of dissolvent of ink around the opening of nozzle, and that an appropriate action of ink discharge is eventually prevented. Conventionally, there has been a technique against the above-mentioned problem, where an ejection action to eject ink from nozzles is performed for adjustment of the action of ink discharge from nozzles by limiting the alteration in the characteristics of ink.
In the inkjet recording apparatuses, conventionally, the action of ink discharge from nozzles is regularly inspected. A method of the inspection is, for example, to detect a malfunction in ink discharge from imaging data obtained by taking a picture of a predetermined test image recorded by ink discharge from nozzles onto a recording medium.
As the adjustment ink discharge from nozzles for adjustment or inspection of the action of ink discharge like those (e.g. ink discharge in the above-described ejection action or test image recording) is performed onto a recording medium, there arises a problem that the wasted consumption of recording media increases though it is possible to perform the adjustment or inspection efficiently and rapidly.
Against that problem, disclosed in the patent document 1 is a technique to make better use of a recording medium, where the above-mentioned adjustment discharge is performed onto a specific area of a normal image, such as an area of the recording medium corresponding to an area to be cut out and discarded after recording about the normal image to be recorded or an area of the recording medium corresponding to an area not to be exposed on the outer side as a product.

PRIOR ART DOCUMENTS

PATENT DOCUMENTS

Patent Document 1 Japanese Patent Application Laid Open Publication No. 2003-200593

SUMMARY OF THE INVENTION

PROBLEM TO BE SOLVED BY THE INVENTION

However, in the above-mentioned conventional techniques, an area necessary for adjustment discharge is not provided in some cases due to the irregularity of the size or form of the above-mentioned specific area depending on the content of the normal image to be recorded.
An object of the present invention is to provide an ink jet recording apparatus and a method for controlling an ink jet recording apparatus, which enables adjustment ink discharge onto a recording medium irrespective of the content of the normal image while lowering the wasted consumption of recording media.

MEANS FOR SOLVING THE PROBLEM

In order to achieve the above object, the invention according to claim 1 is an ink jet recording apparatus including:

an ink discharger with at least one nozzle from which ink is discharged;
a discharge control means to cause the ink discharger to perform an adjustment discharge of ink from the nozzle onto a recording medium according to at least either one of an adjustment and an inspection of an ink discharge action from the nozzle; and
a detection means to detect a different property part which is a limited part of the recording medium and which has a property different from a property of an area other than the part,
wherein the discharge control means causes the ink discharger to perform the adjustment discharge from the nozzle in a range of an adjustment discharge region on the recording medium including at least part of the different property part detected by the detection means.

The invention according to claim 2 is the ink jet recording apparatus according to claim 1, including a conveyance means to convey the recording medium,
wherein, in the ink discharger, the nozzle includes multiple nozzles which are arranged in a predetermined width of recording in a width direction perpendicular to a conveyance direction of the recording medium conveyed by the conveyance means,
wherein the discharge control means causes the conveyance means to convey the recording medium and causes the ink discharger to perform the adjustment discharge from the multiple nozzles in the range of the adjustment discharge region on the recording medium being conveyed.
The invention according to claim 3 is the ink jet recording apparatus according to claim 2, wherein the detection means detects the different property part on the upstream side from a position of ink discharge by the ink discharger in the conveyance direction.
The invention according to claim 4 is the ink jet recording apparatus according to any one of claims 1 to 3:

wherein the recording medium to be a target of the adjustment discharge includes a complex recording medium configured with multiple recording medium pieces which are conjoined;
wherein each of the multiple recording medium pieces of the complex recording medium overlaps partially with at least one of other recording medium pieces and is conjoined with the at least one of other recording medium pieces at a section where the recording medium pieces overlap; and
wherein the detection means detects a joint section of the multiple recording medium pieces as the different property part.

The invention according to claim 5 is the ink jet recording apparatus according to claim 2 or 3:

wherein the recording medium to be a target of the adjustment discharge includes a complex recording medium configured with multiple rectangular recording medium pieces which are conjoined to extend in a direction parallel to a side of the rectangular pieces;
wherein each of the recording medium pieces of the complex recording medium overlaps partially with at least one of other recording medium pieces and is conjoined with the at least one of other recording medium pieces at a section where the recording medium pieces overlap;
wherein the conveyance means conveys the complex recording medium in a state where a longitudinal direction of the conjoined multiple recording medium pieces is parallel to the conveyance direction;
wherein the detection means detects a joint section extending in the width direction of the multiple recording medium pieces as the different property part; and
wherein the discharge control means causes the ink discharger to perform the adjustment discharge from the multiple nozzles in the range of the adjustment discharge region which is a predetermined range from the different property part in the conveyance direction.

The invention according to claim 6 is the ink jet recording apparatus according to any one of claims 1 to 5, wherein the recording medium is pulled out from a recording medium winder on which the recording medium is rolled.
The invention according to claim 7 is the ink jet recording apparatus according to any one of claims 1 to 6, wherein the discharge control means causes the ink discharger to perform an ejection action to eject ink from the nozzle in the range of the adjustment discharge region on the recording medium.
The invention according to claim 8 is the ink jet recording medium according to any one of claims 1 to 7, wherein the discharge control means causes the ink discharger to perform the adjustment discharge from the nozzle to record a predetermined test image used for the inspection of the ink discharge action in the range of the adjustment discharge region on the recording medium.
The invention according to claim 9 is the ink jet recording apparatus according to any one of claims 1 to 8, wherein the discharge control means causes the ink discharger to discharge ink from the nozzle to record a normal image to be recorded outside the adjustment discharge region on the recording medium.
In order to achieve the above object, the invention according to claim 10 is a method for controlling an ink jet recording apparatus which has an ink discharger with a nozzle from which ink is discharged, the method including:

a discharge step to cause the ink discharger to perform an adjustment discharge of ink from the nozzle onto a recording medium according to at least either one of an adjustment and an inspection of an ink discharge action from the nozzle; and
an detection step to detect a different property part which is a limited part of the recording medium and which has a property different from a property of an area other than the part;
wherein, in the discharge step, the ink discharger is caused to perform the adjustment discharge from the nozzle in a range of an adjustment discharge region on the recording medium including at least part of the different property part detected in the detection step.

EFFECTS OF THE INVENTION

The present invention has an effect of performing adjustment ink discharge onto a recording medium irrespective of the content of the normal image while lowering the wasted consumption of recording media.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows an outlined configuration of the ink jet recording apparatus.
Fig. 2 is a schematic drawing showing a configuration of a head unit.
Fig. 3 is an explanatory drawing of a method of detecting a joint section by a joint section detector.
Fig. 4 is a block diagram showing a main functional configuration of the ink jet recording apparatus.
Fig. 5 is an exemplary drawing of an ejection band recorded by the ink jet recording apparatus.
Fig. 6 is a block diagram showing a functional configuration concerning control of an ejection action in a head controller.
Fig. 7 is a flowchart showing a control procedure of image recording by a controller and head controller.
Fig. 8A is another exemplary drawing of a detection means.
Fig. 8B is another exemplary drawing of a detection means.
Fig. 9A is another exemplary drawing of a different property part and an adjustment discharge region in a recording medium.
Fig. 9B is another exemplary drawing of ae different property part and an adjustment discharge region in a recording medium.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

Hereinafter described is an embodiment of the ink jet recording apparatus and a method for controlling an ink jet recording apparatus in accordance with the present invention with reference to the drawings.
FIG. 1 shows an outlined configuration of an ink jet recording apparatus 1 according to the embodiment of the present invention.
The ink jet recording apparatus 1 includes a conveyor 10 (conveyance means), a recorder 20, a controller 30, a medium detector 40, etc.
The conveyor 10 includes a driving roller 11, a driven roller 12, a conveyance belt 13, a conveyance motor 14, a rotary encoder 15, a pressing roller 16, a separating roller 17, etc.
The driving roller rotates on a rotation axis, being driven by the conveyance motor 14. The conveyance belt 13 is a loop belt which is supported inside by the driving roller 11 and the driven roller 12 and circles according to the rotating action of the driving roller 11. The driven roller 12 rotates on a rotation axis parallel to the rotation axis of the driving roller 11 in accompany with the circling movement of the conveyance belt 13. A material which flexibly bends on the contacting face the driving roller 11 and the driven roller 12 and reliably supports a recording medium M is used for the conveyance belt 13 (e.g. belt of resin such as rubber, belt of steel, etc.). The recording medium M may be more reliably placed on the conveyance belt 13 with a material and/or configuration which causes the recording medium M to be sucked to the conveyance belt 13.
The conveyance motor 14 causes the driving roller 11 to rotate at the rotation speed according to the control signals from the controller 30. The conveyance motor 14 may also be able to cause the driving roller 11 to rotate reversely in inverse of the regular conveyance direction. The conveyor 10 performs a conveyance action to convey the recording medium M in the direction of movement of the conveyance belt 13 (conveyance direction) with the conveyance belt 13 circling at a speed according to the rotation speed of the driving roller 11 in a state where the recording medium M is placed on the conveyance face of the conveyance belt 13.
The recording medium M may be conveyed intermittently, with a break during the ink discharge in the conveyor 10, for example. The conveyance operation of the conveyor 10 here includes the actions of taking a break from conveyance, as described above.
In this embodiment, fabric is used for the recording medium M. The recording medium M is pulled out (wound) from the roll (recording medium winder) on which the recording medium M is rolled, and is supplied onto the conveyance belt 13. The recording medium M is a complex recording medium with a configuration where multiple rectangular recording medium pieces Mp (FIG. 3) are conjoined to extend in a direction parallel to the sides of the rectangular pieces (longitudinal direction). A recording medium piece Mp is approximately 2 m in width in the width direction perpendicular to the conveyance direction and approximately 80 m in length in the conveyance direction. The recording medium M is approximately 4000 m in length as a whole roll. The recording medium M is conveyed by the conveyor 10 such that the side extended in the longitudinal direction of the conjoined multiple recording medium pieces Mp is parallel to the conveyance direction. In the recording medium M, each of multiple recording medium pieces Mp is overlapped with another recording medium piece Mp at the joint section R1 (FIG. 3) (i.e. edge parts of recording medium pieces Mp are overlapped with one another), and is conjoined by being sewed on another recording medium piece Mp at the overlapping sections with needles not shown in the drawings. In this embodiment, the thickness of the recording medium M is approximately 100 to 200 µm (twice the thickness at the joint sections R1). However, a thicker recording medium M may be used, as long as ink may be discharged from the recorder 20.
As described above, the conveyor 10 in this embodiment is configured to be able to convey a large recording medium M of 2 m in width in the width direction perpendicular to the conveyance direction. The conveyor 10 may convey a recording medium M smaller than 2 m in width in the width direction. The conveyor 10 may be configured to be able to convey a recording medium M larger than 2 m (e.g. approx. 4 m) in width in the width direction. The maximum width of a conveyable recording medium M may be smaller than 2 m in the width direction.
The recording medium is not limited to fabric as mentioned above, and various kinds of media on the surface of which ink may be fixed, such as paper, sheet resin, etc. may be used.
The rotary encoder 15 outputs a pulse signal (detection signal) to the controller 30 and the head controller 211 (FIG. 4) every time the driving roller 11 rotates at a predetermined angle. The rotary encoder 15 may be, for example, configured to have a code wheel which has multiple slits arranged on a predetermined circumference and rotates in accompany with the driving roller 11, a light source which throws light upon the slits of the code wheel, and a light receiver which detects light emitted by the light source and passing through the slits, and to output pulse signals based on the results of light detection by the light receiver to the controller 30 and the head controller 211, though not limited thereto. The pulse signals here may be output at timings of rise and fall of each of two square waves (phase A and phase B) which have a cycle equal to the cycle of light reception of the light passing through the slits and whose phases are different from one another by an angle of 90°. With such a configuration, the rotation direction of the driving roller 11 may be detected by the phases A and B.
The pressing roller 16 presses the recording medium M supplied to the conveyance face of the conveyor belt 13 against the conveyance face to remove gaps of the recording medium M from the conveyance face, such as wrinkles.
The separating roller 17 pulls the recording medium M which is conveyed thereto by a predetermined force while being sucked to the conveyor belt 13 to separate the recording medium M from the conveyance face, and sends the separated recording medium M to finishing units not shown in the drawings. In this embodiment, the following are included as finishing devices: a dryer to dry the recording medium M on which an image is recorded, a device to steam the recording medium M to produce good colors and to fix ink, a washer to wash out stains or ink not yet fixed, a cutter to cut the recording medium M on the fore and back sides of the joint sections of the recording medium pieces Mp in the recording medium M, etc. The parts including the joint sections R1 of the recording medium cut by the cutter are discarded.
The recorder 20 includes four head units 21 (ink discharger). Each of the head units 21has multiple recording elements which separately perform the action of ink discharge to discharge ink on the basis of image data, and perform the image recording operation to record an image(s) on the recording medium M conveyed by the conveyor 10 with the multiple recording elements performing the action of ink discharge. In the ink jet recording apparatus 1 in this embodiment, four head units 21 corresponding to respective four inks colored yellow (Y), magenta (M), cyan (C), and black (K) are arranged at predetermined intervals in an order of Y, M, C, K from the upstream side in the conveyance direction of the recording medium M. With such a configuration, the head units 21 form an image(s) corresponding to the ink colors respectively discharged from the recording elements and the ink jet recording apparatus 1 records a colored image(s) to be recorded by superimposing images respectively colored Y, M, C, and K in an identical area of the recording medium M. The number of the head units 21 is not limited to four and may be equal to or smaller than three or equal to or larger than five, according to the number of ink colors of used for the image recording.
FIG. 2 is a schematic drawing showing the configuration of the head unit 21. FIG.2 shows a plane figure of the head unit 21 as a whole viewed from the side facing the conveyance face of the conveyor belt 13.
The head unit 21 includes 54 recording heads 212 which each have multiple recording elements to discharge ink. The recording elements are arranged continuously in the width range of approximately 72 mm in the width direction in each of the recording heads 212. Each of the recording elements of the recording head 212 has a pressure chamber to store ink therein, a piezoelectric element attached on the wall surface of the pressure chamber, and the nozzle(s) 213. In the recording elements, when a driving signal to deform the piezoelectric elements is input, the deformation of the piezoelectric elements deforms the pressure chamber and charges the pressure in the pressure chamber, and ink is discharged from the nozzles 213 communicating with the pressure chamber. The positions of the ink discharge openings of the nozzles 213 in the recording elements are shown in FIG. 2. The arrangement direction of the recording elements in each of the recording head 212 is not limited to the width direction perpendicular to the conveyance direction and may be a direction intersecting with the conveyance direction other than at right-angle.
In the head unit 21, a head module 212 M is configured with two recording heads 212 which are arranged next to one another in the conveyance direction such that the nozzles 213 of the recording elements are arranged alternately in the width direction. In the head unit 21, a line head is configured with 27 head modules 212M which are arranged in a staggered pattern such that the positional range in the width direction partially overlap one another, in the positional relationship where the ink dischargeable range from the nozzles is successive and continuous in a width of recording image(s) (approx. 2 m) in the width direction. The head units 21 are used at the fixed positions during the image recording. As the head units 21 discharge ink consecutively at predetermined intervals at positions different in the conveyance direction in accompany with the conveyance of the recording medium M and the image(s) is recorded in a single pass mode. The number of the head modules 212M (corresponding to the number of the recording heads 212) may be suitably varied according to the length of the recording medium M in the width direction.
In the head unit 21, the distance between the ink discharge face on which the nozzles 213 are arranged and the conveyance face of the conveyance belt 13 is approximately 2 to 4 mm.
The medium detector 40 includes a joint section detector 41 (detection means) and a malfunction detector 42.
FIG. 3 is an explanatory drawing of the method of detecting the joint section R1 by the joint section detector 41.
The joint section detector 41 is arranged on the upstream side in the conveyance direction from the ink discharge position of the head units 21 and detects the joint section R1 (different property part) which joins multiple recording medium pieces Mp of the recording medium M pulled out from the roll. The joint section detector 41 includes a light source 411 and a light receiver 412 and detects, with the light receiver 412, the intensity of transmitted light on the recording medium M of the inspection light L which is thrown onto the recording medium M from the light source 411. The light source 411 is arranged on one face of recording medium M to be conveyed (lower side in FIG. 3), and the light receiver 412 is arranged at the position facing the light source 411 with the recording medium M in between on the other face of the recording medium M (upper side in FIG. 3). The intensity of the inspection light L transmitted through the joint section R1 is lower than the intensity of the inspection light L transmitted through the area other than the joint section R1, because two pieces of recording medium Mp overlap at the joint section R1 of the recording medium M. Thus, the joint section detector 41 may detect the fore edge of the joint section R1 in the conveyance direction from the decrease in the intensity of light reception of the light receiver 412. The back edge of the joint section R1 may be detected from the following increase in the intensity of light reception. The joint section detector 41 outputs the detection results of the fore edge and, if necessary, the back edge of the joint section R1 to the controller 30 and the head controller 211.
The malfunction detector 42 is arranged on the downstream side of the joint section detector 41 and on the upstream side of the head units 21 in the conveyance direction, and detects placement abnormalities such as gaps on the recording medium M and errors such as adhesion of trash on the recording medium M and frays of needles at the joint section R1 of the recording medium M with a sensor. The sensor is configured with an emitter to emit laser light in the width direction at a predetermined height above the conveyance face and a detector to detect interception of the laser light due to a gap or trash on the opposite side of the conveyance face in the width detection in this embodiment, though not limited thereto. Alternatively, there may be used a line sensor to detect, by imaging of the upper face of the recording medium M, color irregularities on the surface of the recording medium M due to a trash or shadow at a gap. The malfunction detector 42 is preferably arranged on the upstream side from the head units 21 at a distance which allows the recording medium M to stop moving, in a case where the conveyance of the recording medium M is to be stopped due to a detected malfunction of the recording medium M, before the section of the detected malfunction reaches the position facing the head units 21.
FIG. 4 is a block diagram showing the main functional configuration of the ink jet recording apparatus 1.
The ink jet recording apparatus 1 includes a conveyance driver 101 and the rotary encoder 15 arranged in the conveyor 10, the head controller 211 and the head driver 212a arranged in the head units 21, the controller 30, the joint section detector 41 and the malfunction detector 42 arranged in the medium detector 40, an operation/display unit 51, an input/output interface 52, a bus 53, etc. A discharge control means is configured with the controller 30 and the head controller 211 in this embodiment.
The conveyance driver 101 sends driving signals to the conveyance motor 14 on the basis of control signals sent by the controller 30 to cause the driving roller 11 to rotate at a predetermined speed, further causing the conveyance belt 13 to move at a predetermined motion speed.
The head controller 211 outputs various control signals and image data to the head driver 212a at appropriate timing based on the control signals from the controller 30 and the count of pulse signals input from the rotary encoder 15.
The head driver 212a sends driving signals to the recording elements of the recording heads 212 to deform the piezoelectric elements according to the control signals or the image data input from the head controller 211, causing ink to be discharged from the openings of nozzles 213.
The controller 30 includes a CPU (Central Processing Unit) 31, a RAM 32 (Random Access Memory), a ROM 33 (Read Only Memory), and a storage 34.
The CPU 31 reads out programs for various controls and setting data stored in the ROM 33, stores them in the RAM 32, and executes the programs to perform various kinds of calculation processing. The CPU 31 integrally controls the overall operation of the ink jet recording apparatus 1.
The RAM 32 provides the CPU 31 with working memory space to temporally store data therein. The RAM 32 may include a non-volatile memory.
The ROM 33 stores various programs and setting data to be executed by the CPU 31 therein. A rewritable non-volatile memory such as an EEPROM (Electrically Erasable Programmable Read Only Memory), flash memory, etc. may be used instead of the ROM 33.
The storage 34 stores print jobs (image recording command) input from an external device 2 via the input/output interface 52 and image data concerning the print jobs therein. As the storage 34, an HDD (Hard Disk Drive) is used, for example, and a DRAM (Dynamic Random Access Memory) may be used in combination therewith.
The operation/display unit 51 includes a display such as a liquid crystal display or an organic electroluminescent display, an input device such as operation keys or touch panel superimposed on the screen of the display. The operation/display unit 51 displays various kinds of information on the display, and outputs, to the controller 30, the operation signals generated by conversion of the input operation of a user to the input devices.
The input/output interface 52 intermediates transmission of data between the external device 2 and the controller 30. The input/output interface 52 is configured with, for example, a kind of serial interface, parallel interface, or a combination thereof.
The bus 53 is a path for transmission of signals between the controller 30 and each of other devices.
The external device 2 is a personal computer, for example, and sends the print jobs, image data, etc. to the controller 30 via the input/output interface 52.
Next described is the adjustment of the action of ink discharge in the ink jet recording apparatus 1 according to this embodiment.
In the ink jet recording apparatus 1, the viscosity of ink around the openings of the nozzles 213 increases due to the evaporation of ink dissolvent around the openings, which results in malfunctions in the action of ink discharge (discharge error) where the amount, throwing direction, or throwing speed of ink discharged from the nozzles 213 is deviated from the original setting. In this embodiment, especially, the operation of image recording continues for one hour after the start of the operation of image recording in a case where the conveyance speed is 60 m/min, for example, as a normal image to be recorded is recorded continuously onto the recording medium M which is as long as 4000 m. In the operation of image recording, there may be a nozzle 213 which discharges ink at an extremely low frequency or does not discharge ink at all according to the content of the normal image, and a nozzle 213 like that is subject to malfunctions in the action of ink discharge due to the increased ink viscosity described above in the period of the continuous operation of image recording.
Thus, in the ink jet recording apparatus 1 in this embodiment, in view of preventing occurrence of such malfunctions, the ejection action to eject ink from the nozzles 213 onto the recording medium M being conveyed is performed. Hereinafter the image to be recorded onto the recording medium M by the ejection action is referred to as an ejection band. The ink discharge in the ejection action is an aspect of the adjustment ink discharge of the nozzle 213 for the adjustment of the action of ink discharge.
FIG. 5 is an exemplary drawing of the ejection band recorded by the ink jet recording apparatus 1.
As shown in FIG. 5, the ejection band 62 is recorded by the ejection action in an ink ejection region R2 (adjustment discharge area) extended on the recording medium M in the width direction in the shape of belt in this embodiment. The ejection region R2 includes at least a part of different property part which is a limited part of the recording medium M and which has the property (characteristics and condition) different from that of the other part. The limited part of the recording medium M is smaller than the half of the whole recording medium M here. The different property part is also a part which has the property different from that of the main part of the recording medium M. The main part of the recording medium M here is a part of the recording medium M used for the recording of the normal image where the normal image may be recorded with an appropriate image quality. In the recording medium M in this embodiment, the part which has the same property as that of each recording medium piece Mp before being conjoined is the main part of the recording medium M. Accordingly, in the recording medium M of this embodiment, as the property at the joint section R1 of the recording medium piece Mp is different (in thickness here) from that of the recording medium piece Mp before being conjoined, the joint section R1 is the different property part. The ejection region R2 is set in a predetermined range from the joint section R1 in the conveyance direction, and the ejection band 62 is recorded in the range of the ejection region R2.
On the upstream and downstream sides of the ejection band 62 in the conveyance direction, the normal image 61 is recorded. The normal image 61 is a long image making up of multiple unit images connected to each other in the conveyance direction at the fore and back edges in the conveyance direction, and is recorded uninterruptedly and continuously in the area other than the ejection region R2.
The ejection band 62 is made up of color-by- color ejection bands 62Y, 62M, 62C, and 62K recorded by the respective head units 21 respectively corresponding to Y, M, C, and K. The color-by- color ejection bands 62Y, 62M, 62C, and 62K are recorded, without overlapping with each other, in ranges in the shape of band next to one another in the conveyance direction and extended in the recording range of the nozzles of the head units 21 in the width direction. The recording range of the ejection band 62 in the width direction is equal to the recording range of the normal image 61 in the width direction.
In the ejection action, the ink discharge timings are adjusted so that ink is discharged in the range of the recording medium M in the shape of band (long rectangular) in the conveyance direction according to the position in the conveyance direction of the nozzles 213 arranged in each of the recording heads 212.
Hereinafter described are the method of setting the ejection region R2 on the recording medium M and the control operation to cause the ejection action in the ejection region R2 in the ink jet recording apparatus 1.
As described above, the fore edges of the joint section R1 of the recording medium piece Mp on the recording medium M being conveyed are detected by the joint section detector 41. When the fore edge of the joint section R1 on the downstream side in the conveyance direction is detected, the ejection region R2 is set in the range which includes the whole joint section R1 and whose fore edge is at the position on the downstream side in the conveyance direction from the fore edge of the joint section R1 apart by a predetermined distance d1, as shown in FIG. 3. Here, the length of the ejection region R2 in the conveyance direction is set as small as possible within a range where the whole ejection band 62 may be recorded in view of keeping the recording area of the normal image 61 as large as possible. The distance d1 is set such that the distance d2 between the back edge of the joint section R1 and the back edge of the ejection region R2 in the conveyance direction is generally equal to the distance d1. Because of this, the deviation ranges of the ejection band 62 from the joint section R1 to the upstream and downstream sides may be equal, in a case where the ejection band 62 does not wholly fit inside of the joint section R1.
In a case where the ejection band 62 may be wholly recorded in the joint section R1, the distance d1 may be set to 0. In a case where the length of the ejection band 62 is smaller than the length of the joint section R1 in the conveyance direction, the fore edge of the ejection region R2 may be set on the upstream side from the fore edge of the joint section R1 in the conveyance direction.
When the fore edge of the joint section R1 is detected and the ejection region R2 is set, the ejection action by each of the head units 21 starts at a timing when a predetermined position (edge of the recording range of each of the color-by-color ejection bands) to be the target of the ejection action in the ejection region R2 moves, with the conveyance of the recording medium M by the conveyor 10, to the position of ink discharge by each of the head units 21 (hereinafter the predetermined position is also referred to as the start position of ejection action). As the pulse signals are output from the rotary encoder 15 after the detection of the joint section R1 by the joint section detector 41 in the number predetermined for each head unit 21, it is determined that the start position of ejection action in the ejection region R2 moves to the ink discharge position. The number of the pulse signals corresponds to the distance between the start position of ejection action in the ejection region R2 at the detection of the joint section R1 by the joint section detector 41 and the position of ink discharge by the head unit 21.
FIG. 6 is a block diagram showing the functional configuration concerning the control of the ejection action in the head controller 211.
As shown in FIG. 6, the head controller 211 includes the control circuit 211a, a switching unit 211b and an image data storage 211c. The head controller 211 may be configured with a circuit base board and an FPGA (Field Programmable Gate Array) implemented on the circuit base board, for example, and in this embodiment, the FPGA includes the control circuit 211a, the switching unit 211b, and the image data storage 211c therein. The image data storage 211c may be arranged in the exterior of the FPGA. Other semiconductor integrated circuits such as ASIC (Application Specific Integrated Circuits) may be used instead of the FPGA.
The recording image data D1 of the normal image 61 and the ejection image data D2 used in the ejection action are stored in the image data storage 211c. The ejection image data D2 is image data of color-by-color ejection bands of the colors corresponding to the respective head units 21, which is solid image data in which all the pixel data has the maximum gradation value.
The recording image data D1 and the ejection image data D2 are output to the switching unit 211b under the control by the control circuit 211a. Either one of the recording image data D1 and the ejection image data D2 is output from the switching unit 211b to the head driver 212a of the recording head 212 according to the switching control signals output from the control circuit 211a to the switching unit 211b.
The control circuit 211a outputs, to the head driver 212a, the control signals to cause the action of ink discharge to be performed at appropriate timings. The control circuit 211a outputs the switching control signals to the switching unit 211b to cause the switching unit 211b to output either one of the recording image data D1 and the ejection image data D2 to the head driver 212a line by line. In other words, the control circuit 211a causes the switching unit 211b to output the recording image data D1 to the head driver 212a at the time of recording of the normal image 61. The control circuit 211a starts to send the ejection image data D2 to the head driver 212a by switching the switching unit 211b at the start of ejection action, that is, at the timing when the start position of ejection action in the ejection region R2 of the recording medium M moves to the position of ink ejection by the head unit 21 and continues to send the ejection image data D2 till the timing of the end of the ejection action.
As the ejection image data D2 is solid image data made up of homogeneous pixel data, the predetermined pixel data may be sent repeatedly to the switching unit 211b under the control by the control circuit 211a, instead of the ejection image data D2 read out from the image data storage 211c being sent to the switching unit 211b.
While the normal image 61 is recorded in the area other than the ejection region R2 by the control like that, the ejection action is performed in the discharge region R2 including the joint section R1 of the recording medium piece Mp. In other words, the image generated from the normal image 61 by replacement of the part corresponding to the ejection region R2 with the ejection band 62 is recorded on the recording medium M.
Next described is the image recording process performed in the ink jet recording apparatus 1.
FIG. 7 is a flowchart showing the control procedure of the image recording process by the controller 30 and the head controller 211 in the ink jet recording apparatus 1 in this embodiment.
This image recording process is performed when a print job and the recording image data D1 of the normal image 61 are input from the external device 2 via the input/output interface 52 to the controller 30. Before the start of the image recording process, the controller 30 stores the recording image data D1 in the image data storage 211c in the head controller 211 of each of the head units 21. If the image data of the normal image 61 input from the external device 2 is PDL (Page Description Language) data, the controller 30 stores, in the image data storage 211c, the recording image data D1 generated by conversion of the image data in the raster format.
Following the start of the image recording process, the controller 30 starts the operation of the conveyance motor 14 by outputting the control signals to the conveyance driver 101 to start the conveyance operation by the conveyor 10 and to start the operation of the medium detector 40 (Step S101).
The controller 30 outputs the control signals to the head controller 211 to start the operation of image recording of the normal image 61 by the head units 21 (Step S102). When the start of the operation of image recording is commanded with the control signals from the controller 30, the normal image 61 is recorded as the head controller 211 causes the action of ink discharge of discharging ink onto the recording medium M from the nozzles 213 of the recording heads 212 according to the recording image data D1, by sending the recording image data D1 stored in the image data storage 211c from the switching unit 211b to the head driver 212a at appropriate timings corresponding to the position of recording medium M conveyed by the conveyor 10 which is indicated by the pulse signals from the rotary encoder 15.
The head controller 211 determines whether the joint section detector 41 detects the joint section R1 of the recording medium M (Step S103: detection step), and if it is determined that there is no detection (Step S103: "NO"), the head controller 211 determines whether all the image recording set by the print job is finished (Step S104). If it is determined that the image recording is not finished (Step S104: "NO"), the head controller 211 proceeds to Step S103.
If it is determined that the joint section R1 is detected (Step S103: "YES"), the head controller 211 determines whether the start position of ejection action in the ejection region R2 set according to the detection results of the joint section R1 has moved to the position of ink ejection by the head units 21 (Step S106). The head controller 211 determines here that the start position of ejection action has moved to the position of ink discharge if, after the detection of the joint section R1, the predetermined number of pulse signals from the rotary encoder 15 corresponding to the conveyance distance between the position of ink discharge by the head unit 21 and the start position of ejection action in the ejection region R2 at the timing of detection of the joint section R1 are output. If it is determined that the start position of ejection action has not moved to the position of ink discharge (Step S106: "NO"), the head controller 211 executes again the process of Step S106 while continuing the recording of the normal image 61.
If it is determined that the start position of ejection action has moved to the position of ink discharge (Step S106: "YES"), the head controller 211 causes each of the recording heads 212 to perform the ejection action (Step S107: discharge step). At this step, the head controller 211 switches the switching unit 211b to start sending the ejection image data D2 to the head driver 212a, causing the action of ink ejection from the nozzles 213 of the recording heads 212 according to the ejection image data D2. The head controller 211 continues to send the ejection image data D2 till the timing of the end of the ejection action.
When the ejection action is finished, the head controller 211 restarts the operation of image recording of the normal image 61 (Step S108). In other words, the head controller 211 switches the switching unit 211b to restart sending the recording image data D1 to the head driver 212a, causing the action of ink discharge of discharging ink onto the recording medium M from the nozzles 213 of the recording heads 212 according to the recording image data D1. When the process at Step S108 is finished, the head controller 211 proceeds to Step S104.
If it is determined that all the image recording set by the print job is finished (Step S104: "YES"), the controller 30 and the head controller 211 perform processes to end the image recording (Step S105). Here, the controller 30 stops the conveyance motor 14 and perform an action of notification of the end of image recording. The controller 30 and the head controller 211 delete the settings concerning the print job and the recording image data D1 stored in the storage 34 and the image data storage 211c. Then the controller 30 and the head controller 211 end the image recording process.
The processes at Steps S102 to S108 described above are performed independently by each of the head controllers 211 of the four head units 21.
If the malfunction detector 42 detects a malfunction while the image recording process is being performed, the controller 30 and the head controller 211 interrupt the image recording process. After the image recording process has been interrupted, the user clears the malfunction, or the malfunction handling process is performed, where the head units 21 are put aside from the conveyance face of the conveyance belt 13 and the recording medium M is conveyed till the position of malfunction of the recording medium M is on the downstream side from the head units 21 in the conveyance direction. After that, the image recording process restarts.
The recording medium M on which the normal image 61 and the ejection band 62 are recorded in the image recording process is cut at the positions of boundary of the ejection region R2 in a finishing device, and the parts including the ejection region R2 of the recording medium M after being cut are discarded.
As described hereinbefore, the ink jet recording apparatus 1 in this embodiment includes the head units 21 with the nozzles 213 from which ink is discharged, the controller 30 and the head controller 211 as a discharge control means causing the head units 21 to perform the ejection action onto the recording medium M as the adjustment discharge according to the adjustment of the action of ink discharge from the nozzles 213, and the joint section detector 41 detecting the joint section R1 as the different property part which is a limited part of the recording medium M and which has a property different from that of the other part. The controller 30 and the head controller 211 cause the head units 21 to perform the ejection action in the range of the ejection region R2 on the recording medium M including at least part of the joint part R1 detected by the joint section detector 41. (Discharge control means)
With such a configuration, the ejection action is performed in the ejection region R2 including the joint section R1 where the normal image 61 is not appropriately recorded according to the original property of the recording medium M. Thus, the wasted consumption of the recording medium M is lowered and the decrease in the efficacy of recording the normal image 61 may be restrained, compared with a case where the ejection action is performed in the region where the normal image is appropriately recorded. The ejection region R2 is determined on the basis of the detection results of the different property part of the recording medium M and does not depend on the content of the normal image. Thus, the ejection action may be performed on the recording medium M regardless of the content of the normal image, while the efficacy of recording the normal image 61 is maintained.
The ink jet recording apparatus 1 includes the conveyor 10 conveying the recording medium M. The multiple nozzles 213 are, in the head unit 21, arranged in the predetermined width of recording in the width direction perpendicular to the conveyance direction of the recording medium M by the conveyor 10. The controller 30 and the head controller 211 cause the conveyor 10 to convey the recording medium M and cause the head units 21 to perform the ejection action from the multiple nozzles 213 in the range of the ejection region R2 on the recording medium being conveyed. (Discharge control means) With such a configuration, the ejection action may be performed in a shorter period of time without the head units 21 moving comparatively with the conveyor 10.
The joint section detector 41 detects the joint section R1 on the upstream side in the conveyance direction from the position of ink discharge by the head units 21. Because of this, the ejection region R2 moves to the position of ink discharge of the head units 21 with the conveyance of the recording medium M after the detection of the joint section R1. Thus, the detection of the joint section R1 and the ejection action in the ejection region R2 may be efficiently performed while the conveyance of the recording medium M is being continued.
The recording medium M to be the target of the adjustment discharge includes a complex recording medium configured with multiple recording medium pieces Mp which are conjoined. In the complex recording medium, each of the multiple recording medium pieces Mp overlaps partially with at least one of the other recording medium pieces Mp and is conjoined with that at least one of the other recording medium pieces Mp at the section where they overlap. The joint section detector 41 detects the joint section R1 of the multiple recording medium pieces Mp as the different property part. In this embodiment, especially, the recording medium M is a complex recording medium configured with multiple rectangular recording medium pieces Mp which are conjoined to extend in a direction parallel to the side of the rectangular pieces. The conveyor 10 conveys the recording medium M in a state where the longitudinal direction of the conjoined multiple recording medium pieces Mp is parallel to the conveyance direction. The joint section detector 41 detects the joint section R1 which is extended in the width direction of the multiple recording medium pieces Mp as the different property part. The controller 30 and the head controller 211 cause the head units 21 to perform the ejection action in the range of the ejection region R2 which is a predetermined range from the joint section R1 in the conveyance direction. (Discharge control means)
This enables the ejection action in the ejection region R2 including the joint section R1 which is normally to be cut off and discarded. Thus, the wasted consumption of the recording medium M may be lowered. The ejection action in the joint section R1 where the recording medium pieces Mp overlap may restrain the occurrence of malfunction that the ejected ink permeates through the recording medium M to the bottom surface and stains the conveyance face of the conveyance belt 13.
The recording medium M is pulled out from the roll on which the recording medium M is rolled. The recording of the normal image 61 is successively performed for a long period of time onto such a long recording medium M, and the errors may occur due to the increased viscosity of ink in some of nozzles 213 which discharge ink at a low frequency or do not discharge ink at all according to the content of the normal image 61. However, the occurrence of errors like this may be restrained by the ejection action in the ejection region R2 including the joint section R1 in this embodiment.
The controller 30 and the head controller 211 cause the head units 21 to perform the ejection action to eject ink from the nozzles 213 in the range of the ejection region R2 on the recording medium M. (Discharge control means) This may restrain the occurrence of errors due to the increased ink viscosity around the openings of the nozzles 213.
The controller 30 and the head controller 211 cause the head units 21 to discharge ink from the nozzles 213 outside the ejection region R2 on the recording medium M to record the normal image 61 to be recorded. (Discharge control means) With such a configuration, the normal image 61 may be recorded in a range wider than the range where the normal image 61 may be appropriately recorded. Thus, the efficacy in recording the normal image 61 may be improved.
The control method of the ink jet recording apparatus 1 in this embodiment includes a discharge step to cause the head units 21 to perform the ejection action as the adjustment discharge according to the adjustment of the action of ink discharge from the nozzles 213 onto the recording medium M, and a detection step to detect the joint section R1 as the different property part which is a limited part of the recording medium M and which has a property different from that of the other part. In the discharge step, the head units 21 perform the ejection action in the range of the ejection region R2 on the recording medium M including the joint section R1 detected in the detection step. Such a method may help lower the wasted consumption of the recording medium M, and the ejection action may be performed regardless of the content of the normal image, while the efficacy of recording the normal image 61 is maintained.

(Modification Example)

Next, a modification example of the above embodiment is described. This modification example is different from the above embodiment in that a predetermined test image used for the inspection of the action of ink discharge from the nozzles 213 is recorded onto the recording medium M instead of the ejection action. The features different from those of the above embodiment are described below.
In this modification example, the test image is recorded by the ink discharge from the nozzles 213 of the head units 21 in a test image recording region (adjustment discharge region) set by the same method as used to set the ejection region R2. The test image recording region is set to a range which includes the joint section R1 of the recording medium M and in which the test image to be recoded may be recorded in the conveyance direction. The test image recorded on the recording medium M is imaged by an image reader with a line scan sensor, for example, and the detection of malfunctions in the ink discharge and the adjustment of the action of ink discharge are performed on the basis of the obtained imaging data. The ink discharge from the nozzles 213 to record the test image is an aspect of the adjustment ink discharge from the nozzles 213 for the adjustment or inspection of the action of ink discharge.
The test image to be recorded on the recording medium M is, for example, a lacking point detection chart making up of lines extended in the conveyance direction which are recorded by each of the multiple recording elements of the head units 21, a gray chart of gradation images to detect the variation in the amount of ink discharge among the multiple recording heads 212 of the head unit 21, etc.
In a case where there exist a lacking line or a line not recorded at an appropriate position corresponding to the recording element in the imaging data obtained by the image reader reading the lacking point detection chart as the test image, the recording element corresponding to the line may be determined as a malfunctioned recording element. In a case where a malfunction recording element is detected, a complementing process is set to complement the ink to be discharged from the malfunctioned recording element by increasing the amount of ink discharged from the recording element(s) around the malfunctioned recording element, for example, as well as stopping discharging the ink to be discharged from the malfunctioned recording element.
In a case where a density gap is detected on the gradation image recorded by the multiple recording heads 212 in the imaging data obtained by the image reader reading a gray chart as the test image, the density variation in the recording image is lowered by the adjustment of voltage amplitude of the driving signals sent to the recording elements of each of the recording heads 212 according to the density gap.
In a case where the test image is not appropriately recorded or read because the distance between the ink discharge face of the head units 21 and the recording medium M gets smaller than in the original setting when the test image is recorded on the joint section R1, the test image is preferably to be recorded on the area other than the different property part in the ejection region R2.
Both the ejection action and the recording of the test image may be performed in the area including the joint section R1.
As described hereinbefore, in the ink jet recording apparatus 1 in this modification example, the controller 30 and the head controller 211 cause the head units 21 to perform the adjustment discharge from the nozzles 213 in the range of the ejection region R2 on the recording medium M to record the predetermined test image to be used for the inspection of the action of ink discharge (discharge control means).
As described above, the wasted consumption of the recording medium M may be lowered and the decrease in the efficacy of recording the normal image 61 may be restrained by the recording of the test image in the area which includes the joint section R1 of the recording medium piece Mp and which is to be discarded after being cut out. The recording of the test image on the joint section R1 where the recording medium pieces Mp are overlapped may restrain the occurrence of malfunction that the ejected ink permeates through the recording medium M to the bottom face and stains the conveyance face of the conveyance belt 13 at the time of recording.
The present invention is not limited to the embodiment and modification example described above and various modifications may be made thereto.
For example, in the above embodiment and modification example, the joint section detector 41 detects the joint section R1 on the basis of the intensity of the light transmitted through the recording medium M, exemplarily. However, the configuration of the joint section detector 41 as the detection means is not limited thereto.
Specifically, as shown in FIG. 8A, a joint section detector 41 including an antenna 413 and an earth rod 414 may be used as the detection means, where the antenna 413 bends in accord with the height of the surface of the recording medium M and the earth rod 414 touches the antenna 413 when the antenna 413 bends by touching the joint section R1. Then the joint section detector 41 detects the joint section R1 by the touch of the antenna 413 with the earth rod 414.
As shown in FIG. 8B, alternatively, a joint section detector 41 which includes a roller rotating while moving up and down in accord with the height of the surface of the recording medium M and detects that the roller touches the joint section R1 by the up and down movement may be used as the detection means.
Alternatively, the malfunction detector 42 in the above embodiment may detect the joint section R1. In that case, for example, the emitter of the malfunction detector 42 emits the laser light at the height blocked by the joint section R1 and not blocked by the recording medium M excluding the joint section R1, and the detector detects the laser light.
Moreover, in the above embodiment and modification example, a complex recording medium with multiple rectangular recording medium pieces Mp which are conjoined in the conveyance direction and the joint section R1 of the recording medium pieces Mp being extended in the width direction is used as the recording medium M, exemplarily, though not limited thereto. For example, the multiple recording medium pieces Mp which are conjoined in the width direction instead of or in addition to the conveyance direction with the joint sections being extended in the conveyance direction may be used as the recording medium M. The joint section R1 may be extended in the direction inclined to the width direction and conveyance direction, or may be in a curved form.
In the above embodiment and modification example, the joint section R1 is shown as an example of the different property part of the recording medium M, exemplarily, though the different property part is not limited thereto. A limited part which has a property different from that of the other part of the recording medium M may be the different property part, such as a flaw, stain, hole, or perforation of the recording medium M, for example. The different property part like those may be detected from the imaging data by the image reader with a line sensor, for example.
As shown in FIG. 9A, in a case where the different property part is a hole R1a of the recording medium M, the range within a predetermined distance from the hole R1a in the conveyance direction may be set as the ejection region R2 (adjustment discharge region). The same may be applicable to a case where the different property part is a flaw or stain of the recording medium M.
On the other hand, as shown in FIG. 9B, in a case where the different property part is perforations R1b of the recording medium M of a continuous form sheet, the range within a predetermined distance from the perforations R1b in the conveyance direction may be set as the ejection region R2 (adjustment discharge region).
In a case where the test image is recorded on the recording medium M with a different property part like this, the test image is preferably recorded in the area other than the different property part in the adjustment discharge region so that the test image is appropriately recorded and read.
In the above embodiment and modification example, the recording may be performed onto the recording medium M which is a long complex recording medium pulled out from a roll, exemplarily, though not limited thereto. For example, the recording medium may be a single recording medium piece without a joint section. The recording medium is not limited to one pulled out from a roll and may be in a folded state like switchbacks, for example. The recording medium may be short, like a sheet paper.
In the above embodiment and modification example, the operation of the head driver 212a is controlled by the head controller 211, exemplarily. However, the functions of the head controller 211 like this may be realized by the controller 30.
In the above embodiment and modification example, the ejection action and the recording of the test image are performed in the adjustment discharge region including the different property part on the recording medium M, exemplarily. However, in addition to that, the ejection action and the recording of the test image may be performed in the area outside the adjustment discharge region in a state practically not narrowing the recording region of the normal image 61. For example, the ejection action and the recording of the test image may be performed in margins of the first recording medium piece Mp pulled out from a roll before the start of recording of the normal image 61.
In the above embodiment and modification example, the normal image 61 is uninterrupted and continuous on the recording medium piece Mp, exemplarily, though not limited thereto. The normal image 61 may be images separated for each page.
In the above embodiment and modification example, the driving roller 11 and the driven roller 12 cause the conveyance belt 13 to circle, exemplarily. However, the number of rollers is not limited to two. Alternatively, the conveyance path of the recording medium M is bent with three or more rollers.
In the above embodiment and modification example, the rotary encoder 15 measuring the rotation amount of the driving roller 11 is included, exemplarily, though not limited thereto. An encoder measuring the rotation amount of the driven roller 12, an encoder measuring directly the movement amount of the conveyance belt 13, or an encoder detecting the rotation amount of the conveyance motor 14 may be used, for example.
In the above embodiment and modification example, the conveyor 10 with the conveyance belt 13 conveys the recording medium M, exemplarily, though not limited thereto. The conveyor 10 may convey the recording medium M by holding it on the peripheral surface of a rotating conveyance drum, for example.
In the above embodiment and modification example, the ink jet recording apparatus 1 using a single-pass mode is described as an example. However, the present invention may be applied to an ink jet recording apparatus which records images with the recording heads scanning thereabove.
Although some embodiments of the invention are described, the scope of the invention is not limited to the above embodiments, but includes the scope of the invention described in the scope of claims and the scope of equivalents thereof.

Industrial Applicability

The present invention is applicable to an ink jet recording apparatus and a method for controlling an ink jet recording apparatus.

Description of Reference Numerals

1: Ink Jet Recording Apparatus
2: External Device
10: Conveyor
101: Conveyance Driver
11: Driving Roller
12: Driven Roller
13: Conveyance Belt
14: Conveyance Motor
15: Rotary Encoder
16: Pressing Roller
17: Separating Roller
20: Storage
21: Head Unit
211: Head Controller
211a: Control Circuit
211b: Switching Unit
211c: Image Data Storage
212: Recording Head
212a: Head Driver
212M: Head Module
213: Nozzle
30: Controller
31: CPU
32: RAM
33: ROM
34: Storage
40: Medium Detector
41: Joint Section Detector
411: Light Source
412: Light Receiver
42: Malfunction Detector
51: Operation/Display Unit
52: Input/Output Interface
53: Bus
61: Normal Image
62: Ejection Band
52Y, 62M, 62C, 62K: Color-by-color Ejection Band
D1: Recording Image Data
D2: Ejection Image Data
L: Inspection Light
M: Recording Medium
Mp: Recording Medium Piece
R1: Joint Section
R2: Ejection Region

Claims

An ink jet recording apparatus comprising:
an ink discharger with at least one nozzle from which ink is discharged;

a discharge control means to cause the ink discharger to perform an adjustment discharge of ink from the nozzle onto a recording medium according to at least either one of an adjustment and an inspection of an ink discharge action from the nozzle; and

a detection means to detect a different property part which is a limited part of the recording medium and which has a property different from a property of an area other than the part,

wherein the discharge control means causes the ink discharger to perform the adjustment discharge from the nozzle in a range of an adjustment discharge region on the recording medium including at least part of the different property part detected by the detection means.
The ink jet recording apparatus according to claim 1, comprising a conveyance means to convey the recording medium,
wherein, in the ink discharger, the nozzle includes multiple nozzles which are arranged in a predetermined width of recording in a width direction perpendicular to a conveyance direction of the recording medium conveyed by the conveyance means, and
wherein the discharge control means causes the conveyance means to convey the recording medium and causes the ink discharger to perform the adjustment discharge from the multiple nozzles in the range of the adjustment discharge region on the recording medium being conveyed.
The ink jet recording apparatus according to claim 2, wherein the detection means detects the different property part on the upstream side from a position of ink discharge by the ink discharger in the conveyance direction.
The ink jet recording apparatus according to any one of claims 1 to 3:
wherein the recording medium to be a target of the adjustment discharge includes a complex recording medium configured with multiple recording medium pieces which are conjoined;

wherein each of the multiple recording medium pieces of the complex recording medium overlaps partially with at least one of other recording medium pieces and is conjoined with the at least one of other recording medium pieces at a section where the recording medium pieces overlap; and

wherein the detection means detects a joint section of the multiple recording medium pieces as the different property part.
The ink jet recording apparatus according to claim 2 or 3:
wherein the recording medium to be a target of the adjustment discharge includes a complex recording medium configured with multiple rectangular recording medium pieces which are conjoined to extend in a direction parallel to a side of the rectangular pieces;

wherein each of the recording medium pieces of the complex recording medium overlaps partially with at least one of other recording medium pieces and is conjoined with the at least one of other recording medium pieces at a section where the recording medium pieces overlap;

wherein the conveyance means conveys the complex recording medium in a state where a longitudinal direction of the conjoined multiple recording medium pieces is parallel to the conveyance direction;

wherein the detection means detects a joint section extending in the width direction of the multiple recording medium pieces as the different property part; and

wherein the discharge control means causes the ink discharger to perform the adjustment discharge from the multiple nozzles in the range of the adjustment discharge region which is a predetermined range from the different property part in the conveyance direction.
The ink jet recording apparatus according to any one of claims 1 to 5, wherein the recording medium is pulled out from a recording medium winder on which the recording medium is rolled.
The ink jet recording apparatus according to any one of claims 1 to 6, wherein the discharge control means causes the ink discharger to perform an ejection action to eject ink from the nozzle in the range of the adjustment discharge region on the recording medium.
The ink jet recording medium according to any one of claims 1 to 7, wherein the discharge control means causes the ink discharger to perform the adjustment discharge from the nozzle to record a predetermined test image used for the inspection of the ink discharge action in the range of the adjustment discharge region on the recording medium.
The ink jet recording apparatus according to any one of claims 1 to 8, wherein the discharge control means causes the ink discharger to discharge ink from the nozzle to record a normal image to be recorded outside the adjustment discharge region on the recording medium.
A method for controlling an ink jet recording apparatus which has an ink discharger with a nozzle from which ink is discharged, the method comprising:
a discharge step to cause the ink discharger to perform an adjustment discharge of ink from the nozzle onto a recording medium according to at least either one of an adjustment and an inspection of an ink discharge action from the nozzle; and

an detection step to detect a different property part which is a limited part of the recording medium and which has a property different from a property of an area other than the part;

wherein, in the discharge step, the ink discharger is caused to perform the adjustment discharge from the nozzle in a range of an adjustment discharge region on the recording medium including at least part of the different property part detected in the detection step.