JP2007176118A - Inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a change of a conveyance gap of a paper between in the case where a rear part of the paper is pressed in contact by a paper feeding roller and in the case where the rear part of the paper is released from the pressing of the paper feeding roller in an inkjet recorder, and to reduce a change of the conveyance gap of the paper due to the kind of the paper. <P>SOLUTION: Adjustment patterns different between at a contact time to the paper feeding roller and at a non contact time are printed. Each correction amount when a regular paper is conveyed is calculated by judging a degree of suitableness of the adjustment patterns. Each correction amount to a paper other than the regular paper such as a gloss paper is calculated from the calculated correction amount. A conveyance amount by a conveyance roller is set/controlled by the calculated correction amount. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In the ink jet recording apparatus, there is little change in paper conveyance deviation between the case where the rear portion of the paper is pressed by the paper feed roller and the case where the paper is released from the pressure contact of the paper feed roller. The present invention relates to a technique for reducing a change in paper conveyance deviation due to the above.

2. Description of the Related Art Conventionally, ink jet recording apparatuses that perform image recording on a recording medium by discharging ink stored in an ink tank from a nozzle of a recording head are known.
In such a transport mechanism of an ink jet recording apparatus, a paper feeding unit capable of storing a plurality of sheets cut into A4 size and the like, and a paper feeding unit that separates and feeds the paper stored in the paper feeding unit one by one. A paper roller, a transport roller for transporting the paper sent out by the paper feed roller to the bottom of the recording head, a pinch roller disposed opposite to the transport roller, and a paper after image formation. 2. Description of the Related Art There is known a paper discharge roller that discharges to a paper discharge unit and a pinch roller (a spur roller) that is opposed to the paper discharge roller while being pressed against the paper discharge roller.

Here, the main factors that cause the difference between the theoretical transport amount of the paper transport and the actual transport amount will be described below. The theoretical transport amount refers to a calculated transport amount.
For example, when the radius of the conveyance roller is “r”, the calculated conveyance amount of the sheet by one rotation of the conveyance roller is “2 × π (circumferential ratio) × r”. However, the radius of the transport roller is “r ± δ” due to the manufacturing error ± δ. The actual conveyance amount of the sheet by one rotation of the conveyance roller is “2 × π (circumferential ratio) × (r ± δ)”. Therefore, a difference in the conveyance amount of “2 × π (circumferential ratio) × (± δ)” occurs between the theoretical conveyance amount and the actual conveyance amount.

In addition, when slip occurs between the paper and the transport roller or the paper discharge roller, the theoretical transport amount of the paper is different from the actual transport amount.
Further, the theoretical transport amount and the actual transport amount of the paper are also caused by play (backlash) of a transport roller, a discharge roller, and a drive source for driving them such as a DC motor, for example, a gear coupling mechanism. Is different.

For this reason, the conveyance mechanism of the ink jet recording apparatus is provided with correction means for correcting a conveyance deviation between the theoretical conveyance amount and the actual conveyance amount of the sheet (see, for example, Patent Documents 1 and 2). .
JP 2002-254736 A (page 4) JP 2001-88377 A (page 3)

  However, in the transport mechanism of the ink jet recording apparatus as described above, as described below, the case where the rear portion of the paper is pressed by the paper feed roller and the case where the paper feed roller is released from the pressure contact, There has been a problem in that the conveyance deviation of the paper changes and printing unevenness occurs.

The process of separating and sending out the sheets stored in the sheet feeding unit one by one is executed as follows.
First, the paper feed roller is rotated in a state where the paper feed roller is pressed against the uppermost paper among the paper stacked and placed on the paper feed unit, and only the uppermost paper is separated to separate the uppermost paper. The leading edge of the upper sheet is conveyed to the contact point between the conveying roller and the pinch roller.

  When the transport roller rotates in the transport direction, the sheet is drawn between the transport roller and the pinch roller and is sandwiched between the transport roller and the pinch roller. Thereafter, the sheet is conveyed to the sheet discharge roller side which is the conveying direction along with the rotation of the conveying roller. Note that when the transport roller rotates, the paper feed roller is configured to idle without receiving a rotational force.

  When the leading edge of the sheet is conveyed to the contact point between the conveying roller and the pinch roller and is sandwiched between the conveying roller and the pinch roller, the rear part of the sheet is a non-separated sheet stacked on the sheet feeding roller and the sheet feeding unit. It is left in the position where it was pressed between.

  In this state, when the leading edge of the sheet is conveyed by the conveying roller and the pinch roller, the rear part of the sheet is pressed by the sheet feeding roller and thus receives a conveyance resistance due to a coefficient of friction with the sheet that is not separated. . When the rear portion of the sheet receives conveyance resistance, slip occurs between the conveyance roller and the sheet, and the conveyance deviation of the sheet increases.

  When the sheet is conveyed in the conveying direction by the conveying roller and the pinch roller and the rear part of the sheet is removed from the position of the paper feed roller, the rear part of the sheet is released from the conveyance resistance due to the coefficient of friction with the sheet that is not separated. That is, since the rear portion of the sheet is not subjected to conveyance resistance, slip does not occur between the conveyance roller and the sheet, and conveyance deviation of the sheet is reduced.

  Therefore, there is a problem in that the paper conveyance deviation changes between the case where the rear portion of the paper is pressed by the paper feed roller and the case where the rear of the paper is released from the pressure contact of the paper feed roller, and printing unevenness occurs.

  In particular, in high-quality printing such as photographs, printing unevenness due to a change in paper conveyance deviation becomes more obvious than in general printing. In high-quality printing such as photographs, printing on glossy paper is more frequent than printing on ordinary plain paper.

  For example, in a plain paper having a thickness of about 90 μm, the friction coefficient between the paper and the paper is about 0.4, but in a glossy paper having a thickness of about 225 μm, the friction coefficient between the paper and the paper is about 0.6. That is, the friction coefficient between glossy paper sheets with a thickness of about 225 μm is about 1.5 times the friction coefficient between plain paper sheets with a thickness of about 90 μm. Therefore, the conveyance resistance received by the rear part of the paper when the rear part of the paper is pressed by the paper feed roller is larger in the case of glossy paper than in the case of plain paper. Therefore, when printing on glossy paper, compared to plain paper, paper is transported when the rear part of the paper is pressed by the paper feed roller and when it is released from the pressure of the paper feed roller. There has been a problem that the change in misalignment becomes large and printing unevenness becomes more apparent.

  In addition, in order to improve the operability of storing paper in the paper feed unit, an ink jet recording apparatus in which the paper feed unit is provided on the front side has appeared. In such an ink jet recording apparatus, the sheets separated and sent one by one by the sheet feed roller from the sheet feed unit provided on the front side are reversed 180 degrees and discharged from the discharge roller on the front side. That is, the sheet is conveyed so as to draw a 180-degree curvature (hereinafter referred to as curvature conveyance). Then, compared to the case where the sheet is conveyed linearly, the sheet is more easily subjected to conveyance resistance by the conveyance guide when the sheet is conveyed with curvature. In other words, the sheet conveyed with curvature is pressed against the conveyance guide by the rigidity of the sheet, and is subjected to conveyance resistance due to its frictional resistance.

  In such an ink jet recording apparatus, further downsizing of the apparatus is required. In particular, it is required to reduce the size in the height direction in which the apparatus is installed. Therefore, when the sheet is conveyed with curvature, it is required to make the curvature radius smaller. The conveyance resistance received by the sheet increases as the radius of curvature decreases. Therefore, the conveyance resistance received by the sheet is further increased by downsizing the apparatus.

Further, as will be described below, glossy paper frequently used in high-quality printing such as photographs has a higher conveyance resistance than plain paper. For example, in a general plain paper having a thickness of about 90μm to be used in printing, the stiffness of the paper is about 80 cm ^3/100, in the glossy paper having a thickness of about 225 .mu.m, stiffness of the paper is about 450 cm ³ / 100. That is, the rigidity of glossy paper having a thickness of about 225 μm is about 5.6 times that of plain paper having a thickness of about 90 μm. Therefore, the conveyance resistance due to the frictional resistance by which the sheet is pressed against the conveyance guide due to the rigidity of the sheet is larger in the case of glossy paper than in the case of plain paper.

  Accordingly, the sheet transport resistance varies depending on the type of paper to be printed, such as plain paper or glossy paper. In other words, there is a problem that the conveyance deviation of the paper changes depending on the type of the paper and printing unevenness occurs.

  This problem can be solved by correcting the amount of paper transported by the transport roller when the rear part of the paper is pressed by the paper feed roller and when released from the pressure contact of the paper feed roller. There is little change in the paper conveyance deviation between the case where the rear part is pressed by the paper feed roller and the case where it is released from the pressure contact of the paper supply roller, and the change in the paper conveyance deviation due to the type of paper is reduced. It is expected that a configured ink jet recording apparatus will appear.

  However, the ink jet recording apparatus as described above has the following problems. That is, it is expected that the correction amount of the appropriate transport amount is different between the first half and the second half when transporting the paper, and the position of the ink adhering (landing) to the paper and the assumed control position are the first half of the paper. When the transport amount by the transport roller is corrected so as to match, the ink position and the assumed control position are different in the second half of the sheet, while the ink position (landing) on the sheet and the control position When the transport amount by the transport roller is corrected so that the assumed position matches the latter half of the sheet, it is expected that the ink position and the assumed position in the control are different in the first half of the sheet.

  The present invention has been made in view of such problems, and the object of the present invention is based on the case where the rear portion of the paper is pressed by the paper feed roller and the case where the rear of the paper is released from the pressure contact of the paper feed roller. An object of the present invention is to provide an ink jet recording apparatus in which a change in paper conveyance deviation is small and a change in paper conveyance deviation due to the type of paper is small.

  The ink jet recording apparatus according to claim 1, which has been made to solve the above-described problem, “prints different test patterns depending on whether the paper feed roller is in contact with the non-contact state, and determines an appropriate degree of the test pattern. The correction amount when the sheet is conveyed is calculated respectively in step, and the conveyance means is controlled by the calculated correction amount.

  Specifically, the above-described ink jet recording apparatus has a recording head capable of selectively ejecting ink toward a sheet, a carriage mounted with the recording head and reciprocating in a predetermined direction, and a plurality of sheets of paper can be stored. The paper feed roller, the paper feed roller that separates and feeds the paper stored in the paper feed tray one by one, and the paper feed roller sends the paper from the paper feed tray when ink is not ejected. The conveyance roller that intermittently conveys the paper in a direction substantially perpendicular to a predetermined direction and the paper feed roller are controlled to feed the paper stored in the paper feed tray, and the recording head, carriage, and conveyance roller are controlled. In this way, a printing process for recording an image on a sheet is performed by repeatedly performing carriage movement, ink ejection by a recording head, and intermittent conveyance by a conveyance roller. And means, the.

  The above-described inkjet recording apparatus includes a test pattern storage unit that stores a contact test pattern and a non-contact test pattern, a determination unit, a calculation unit, a correction amount storage unit, and a detection unit that detects a paper type. And comprising. Here, the contact test pattern refers to a test pattern for inspecting the image recording condition by the recording head by recording an image on a sheet conveyed by the conveying roller while being in contact with the sheet feeding roller. The contact test pattern refers to a test pattern for inspecting the image recording condition by the recording head by recording an image on a sheet conveyed by the conveying roller without contacting the sheet feeding roller. When the paper is transported by the transport roller while being in contact with the paper feed roller, the control unit reads the contact test pattern from the test pattern storage unit, and controls the recording head, the carriage, and the transport roller. Then, the read test pattern at the time of contact is recorded on the paper. On the other hand, when the sheet is transported by the transport roller without being in contact with the paper feed roller, the control unit reads the above-mentioned non-contact test pattern from the test pattern storage unit, and moves the recording head, carriage, and transport roller. The read-out non-contact test pattern is controlled to be image-recorded on the paper. Further, the determination means determines the appropriate degree of the test pattern at the time of contact recorded on the paper and the appropriate degree of the test pattern at the time of non-contact recorded on the paper.

  Then, the calculation means calculates the contact correction amount and the non-contact correction amount according to the appropriate degree determined by the determination means. The contact correction amount is a correction amount for correcting the transport amount when the paper is transported by the transport roller while being in contact with the paper feed roller. The non-contact correction amount is a paper feed amount. A correction amount for correcting the conveyance amount when the sheet is conveyed by the conveyance roller without contacting the roller. Note that the correction amount storage means stores the correction amount calculated by the calculation means. Then, the control unit reads the correction amount from the correction amount storage unit, and controls the transport unit based on the read correction amount when executing the printing process.

  According to the ink jet recording apparatus of the present invention configured as described above, different test patterns are printed depending on whether or not the paper feed roller is in contact, and the sheet is conveyed by determining the appropriate degree of the test pattern. The correction amount at the time of carrying out is calculated, and the conveying means is controlled by the calculated correction amount. As a result, there is little change in the paper conveyance deviation between when the rear part of the paper is pressed by the paper feed roller and when the paper is released from the pressure contact of the paper feed roller, and the paper conveyance deviation due to the type of paper is small. The change of can be reduced.

  Further, according to the ink jet recording apparatus of the present invention configured as described above, the correction amount for correcting the paper transport amount by the transport unit is calculated for each ink jet recording apparatus. The conveying means can be controlled with high accuracy based on the correction amount.

  By the way, other types of paper such as glossy paper are different in thickness and rigidity from standard types of paper such as plain paper, so when transporting other types of paper such as glossy paper, When the transport means is controlled based on the correction amount set when transporting standard types of paper such as plain paper, the rear part of the paper is pressed by the paper feed roller and released from the pressure of the paper feed roller. There is a possibility that a change in the conveyance deviation of the paper due to the case of being made becomes large.

  Accordingly, it is conceivable to calculate the correction amounts for other types of paper such as glossy paper from the correction amounts for standard types of paper such as plain paper, and to control the conveying means with the calculated correction amounts. Specifically, as described in claim 2, the apparatus includes a detecting unit that detects the type of the sheet, and the calculating unit conveys the sheet of a type other than the standard type by the conveying roller while contacting the sheet feeding roller. In addition to calculating the other type contact correction amount for correcting the conveyance amount in the case based on the above-described contact correction amount, the conveyance roller without contacting a paper of a type other than the standard type with the paper feed roller The other type non-contact correction amount for correcting the transport amount when transported by the above is calculated based on the above-mentioned non-contact correction amount, and the correction amount storage means stores the correction amount calculated by the calculation means. The control unit reads the correction amount corresponding to the paper type detected by the detection unit from the correction amount storage unit, and controls the transport unit based on the read correction amount when executing the printing process. It is done.

  With this configuration, it is only necessary to determine the degree of conformity of the test pattern to a standard type of paper such as plain paper, and standard paper such as plain paper is also used when transporting other types of paper such as glossy paper. As in the case of transporting various types of paper, there is little change in the paper transport deviation between the case where the rear part of the paper is pressed by the paper feed roller and the case where the paper is released from the pressure contact of the paper feed roller, It is possible to reduce the change in paper conveyance deviation due to the type of paper. Therefore, it is possible to reduce the cost required for adjusting the ink jet recording apparatus at the time of manufacturing, and to reduce the manufacturing cost.

  By the way, it is conceivable that the inspector or the like confirms the appropriate degree of the test pattern recorded on the paper, and the determining means determines the appropriate degree based on the confirmation result. Specifically, as in claim 3, the input means for inputting the information indicating the appropriate degree of the test pattern at the time of contact recorded on the paper and the appropriate degree of the test pattern at the time of non-contact recorded on the paper. And the determining means includes a test pattern of the contact test pattern recorded on the sheet in accordance with information indicating the appropriate degree of the test pattern at the time of contact and the appropriate degree of the test pattern at the time of non-contact input by the input means. It is conceivable to determine the appropriate degree and the appropriate degree of the non-contact test pattern recorded on the paper.

  Further, it is conceivable to determine the appropriate degree of the test pattern recorded on the paper based on the image read by the reading unit. Specifically, as described in claim 4, a determination for storing a determination criterion for determining an appropriate degree of the test pattern for contact recorded on the sheet and the test pattern for non-contact recorded on the sheet. A reference storage unit; and a reading unit that reads a contact test pattern recorded on the sheet and a non-contact test pattern recorded on the sheet. The determination unit stores the determination stored in the determination reference storage unit. With reference to the reference, it is conceivable to determine the appropriate degree of the test pattern at the time of contact and the appropriate degree of the test pattern at the time of non-contact read from the paper by the reading unit.

  With this configuration, it is possible to automatically determine the appropriate degree of the test pattern recorded on the paper. For example, the inspector confirms the appropriate degree of the test pattern recorded on the paper. Compared to the case of inputting, it is possible to reduce the burden on the inspector at the time of manufacturing and reduce the number of manufacturing steps.

  If the resolution at the time of image reading by the reading means described above is low, there is a possibility that the test pattern recorded on the paper cannot be read well. Therefore, the above-described reading means records the test pattern on contact and the image recorded on the paper at a resolution more than twice the test pattern recorded on the paper by the recording head. It is conceivable that the non-contact test pattern can be read.

If comprised in this way, the test pattern recorded on the paper can be read well.
By the way, it is conceivable that the reference correction value for correcting the carry amount differs between the contact pattern and the non-contact pattern recorded on the paper. In this way, in the multiple patterns in the test pattern, the appropriate pattern is placed in the center for both the contact pattern and the non-contact pattern, so the adjustment area can be expanded or the number of patterns can be reduced even with the same number of patterns. can do.

  Further, the contact pattern and the non-contact pattern recorded on the paper are considered to be substantially the same pattern (claim 7). In this way, the pattern of the main scanning operation in which the recording head ejects ink can be shared, and the amount of memory used can be reduced.

  In addition, for the test pattern image recording on the paper described above, paying attention to the fact that the transport amount of the paper when the paper feed roller is not in contact with the paper is stable, the test pattern when not in contact with the paper feed roller Is printed, and the appropriate amount of the test pattern is determined to calculate the correction amount when the standard paper is conveyed, and the correction amount at the time of contact with the paper feed roller is calculated from the calculated correction amount. It is possible.

  Specifically, as in claim 8, when the test pattern storage means stores the above-mentioned non-contact test pattern and the sheet is conveyed by the conveyance roller without contacting the paper feed roller. The control means reads the non-contact test pattern from the test pattern storage means, controls the recording head, the carriage and the transport roller to record the read non-contact test pattern on the paper. The determining means determines the appropriate degree of the non-contact test pattern recorded on the paper. Then, the calculation unit corrects the conveyance amount when the standard type of paper is conveyed by the conveyance roller without being in contact with the paper feed roller according to the appropriate degree determined by the determination unit. At the time of contact to calculate the correction amount at the time of contact, and to correct the transport amount when the standard type of paper is transported by the transport roller while being in contact with the paper feed roller based on the calculated correction amount at the time of non-contact A correction amount is calculated. Note that the correction amount storage means stores the correction amount calculated by the calculation means. Then, the control unit reads the correction amount from the correction amount storage unit, and controls the transport unit based on the read correction amount when executing the printing process.

  With this configuration, it is only necessary to record one test pattern on a sheet of paper, so that the number of determination steps for determining the appropriate degree of a test pattern is reduced as compared with the case of recording a plurality of test patterns on a sheet of paper. can do. Therefore, it is possible to reduce the cost required for adjusting the ink jet recording apparatus at the time of manufacturing, and to reduce the manufacturing cost.

  In addition, since the test pattern storage means only needs to store one test pattern, the storage capacity can be reduced correspondingly, compared with the case where the test pattern storage means stores a plurality of test patterns, and the manufacturing cost can be reduced. Can be reduced.

  By the way, other types of paper such as glossy paper are different in thickness and rigidity from standard types of paper such as plain paper, so when transporting other types of paper such as glossy paper, When the transport means is controlled based on the correction amount set when transporting standard types of paper such as plain paper, the rear part of the paper is pressed by the paper feed roller and released from the pressure of the paper feed roller. There is a possibility that a change in the conveyance deviation of the paper due to the case of being made becomes large.

  Accordingly, it is conceivable to calculate the correction amounts for other types of paper such as glossy paper from the correction amounts for standard types of paper such as plain paper, and to control the conveying means with the calculated correction amounts. Specifically, as in claim 9, there is provided detection means for detecting the paper type, and the calculation means conveys the paper of a type other than the standard type by the transport roller while contacting the paper feed roller. In addition to calculating the other type contact correction amount for correcting the conveyance amount in the case based on the above-described contact correction amount, the conveyance roller without contacting a paper of a type other than the standard type with the paper feed roller The other type non-contact correction amount for correcting the transport amount when transported by the above is calculated based on the above-mentioned non-contact correction amount, and the correction amount storage means stores the correction amount calculated by the calculation means. The control unit reads the correction amount corresponding to the paper type detected by the detection unit from the correction amount storage unit, and controls the transport unit based on the read correction amount when executing the printing process. It is done.

  With this configuration, it is only necessary to determine the degree of conformity of the test pattern to a standard type of paper such as plain paper, and standard paper such as plain paper is also used when transporting other types of paper such as glossy paper. As in the case of transporting various types of paper, there is little change in the paper transport deviation between the case where the rear part of the paper is pressed by the paper feed roller and the case where the paper is released from the pressure contact of the paper feed roller, It is possible to reduce the change in paper conveyance deviation due to the type of paper. Therefore, it is possible to reduce the cost required for adjusting the ink jet recording apparatus at the time of manufacturing, and to reduce the manufacturing cost.

  By the way, it is conceivable that the inspector or the like confirms the appropriate degree of the test pattern recorded on the paper, and the determining means determines the appropriate degree based on the confirmation result. Specifically, as in claim 10, the information processing apparatus includes an input unit that inputs information indicating an appropriate degree of the non-contact test pattern recorded on the sheet, and the determination unit is input by the input unit. It is conceivable to determine the appropriateness of the non-contact test pattern recorded on the paper according to information indicating the appropriateness of the non-contact test pattern.

  Further, it is conceivable to determine the appropriate degree of the test pattern recorded on the paper based on the image read by the reading unit. Specifically, as described in claim 11, a criterion storage means for storing a criterion for determining an appropriate degree of the non-contact test pattern recorded on the sheet, and an image recorded on the sheet Reading means for reading a test pattern at the time of non-contact, and the determination means refers to the determination criteria stored in the determination reference storage means, and determines the appropriate degree of the non-contact test pattern read from the paper by the reading means, respectively. It is possible to judge.

  With this configuration, it is possible to automatically determine the appropriate degree of the test pattern recorded on the paper. For example, the inspector confirms the appropriate degree of the test pattern recorded on the paper. Compared to the case of inputting, it is possible to reduce the burden on the inspector at the time of manufacturing and reduce the number of manufacturing steps.

  If the resolution at the time of image reading by the reading means described above is low, there is a possibility that the test pattern recorded on the paper cannot be read well. Therefore, the above-mentioned reading means can read the non-contact test pattern recorded on the paper at a resolution more than twice the test pattern recorded on the paper by the recording head. It is conceivable (claim 12). If comprised in this way, the test pattern recorded on the paper can be read well.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
FIG. 1 shows a multi-function device (MFD) to which an image forming system of the present invention is applied.
Device)) is a perspective view, and FIG. 2 is a side sectional view thereof.

[Description of Configuration of Multifunctional Device 1]
The multi-function device 1 of the present embodiment has a printer function, a copy function, a scanner function, and a facsimile function, and can be fed into the bottom of a synthetic resin housing 2 through an opening 2a on the front side. A paper cassette 3 is provided.

  The paper feed cassette 3 is configured to be capable of storing a plurality of sheets P cut into, for example, A4 size or legal size, and the short side of each sheet P is in the sheet transport direction (sub-scanning direction and X axis). In parallel with the direction substantially coincident with the main scanning direction and the Y-axis direction.

  At the front end of the paper feed cassette 3, an auxiliary support member 3a for supporting a long paper P portion such as a legal size is mounted so as to be movable in the X-axis direction. FIG. 2 shows an example in which the auxiliary support member 3a protrudes from the housing 2 to the outside. The member 3a can be accommodated so as not to interfere with paper feeding.

  Further, a bank portion 5 for separating paper is disposed on the rear side of the paper feed cassette 3. The multi-function device 1 is configured such that a base end portion of a paper feed arm 9a that constitutes a paper feed unit 9 is attached to a bottom plate of a box-type main frame 7 made of a metal plate so as to be rotatable in the vertical direction. The paper P stacked on the paper feed cassette 3 is separated and conveyed one by one by the paper feed roller 9b provided at the lower end of the paper feed arm 9a and the bank 5. The separated paper P is transported to the image forming unit 13 provided above (higher position) than the paper feed cassette 3 via the U-turn path 11 constituting the U-shaped transport path.

[Description of Configuration of Image Forming Unit 13]
The image forming unit 13 includes a carriage 17 and the like that can reciprocate in the main scanning direction on which an ink jet recording head 15 is mounted. The carriage 17 is controlled by a CPU 60 to be described later, and the recording head 15 is moved in the main scanning direction. Scan. The recording head 15 ejects ink at the time of scanning, and forms an image on the paper P stopped and disposed under the recording head 15. At this time, the paper P is supported from below by the platen 19 constituting the transport path. That is, the recording head 15 is positioned immediately above the platen 19, and image formation on the paper P by the recording head 15 is performed on the platen 19.

  The paper discharge unit 21 from which the paper P on which the image is formed by the image forming unit 13 is discharged is formed on the upper side of the paper feed cassette 3, and a paper discharge port 21 a communicating with the paper discharge unit 21 is provided on the front surface of the housing 2. The opening 2a is opened in common.

[Description of Configuration of Image Reading Device 23]
Further, an image reading device 23 used for reading a document is disposed on the upper portion of the housing 2. The image reading device 23 is arranged so that its bottom wall 23a is superimposed from above the upper cover body 25 with almost no gap, and is vertically opened and closed with respect to one side end of the housing 2 via a pivot portion (not shown). Has been made possible. Further, the rear end of the document cover body 27 covering the upper surface of the image reading device 23 is attached to the rear end of the image reading device 23 so as to be rotatable up and down around the pivot 23b.

  In addition, the image reading device 23 can read the adjustment pattern recorded on the paper at a resolution more than twice the adjustment pattern recorded on the paper by the recording head 15 described later.

[Description of configuration of operation panel unit 29 and the like]
In addition, an operation panel unit 29 including various operation buttons, a liquid crystal display unit, and the like is provided in front of the image reading device 23. On the upper surface of the image reading device 23, there is provided a placement glass plate 31 on which the document cover body 27 can be opened upward and a document can be placed. A contact image sensor) 33 is provided to be reciprocally movable along a guide shaft 35 extending in the main scanning direction (Y-axis direction).

  In addition, an ink storage unit (not shown) that opens upward is provided at the front of the housing 2 that is covered by the image reading device 23. The ink storage unit is detachably mounted with ink cartridges each containing four colors (black, cyan, magenta, yellow) for full color recording. In the multi-function device 1 of the present embodiment, the ink stored in the ink cartridge is supplied to the recording head 15 via a plurality of ink supply pipes 37 connecting the ink cartridges and the recording head 15.

[Description of configuration of paper transport system]
Next, a paper transport system provided in the multi-function device 1 will be described. FIG. 3 is an explanatory diagram showing a schematic configuration of the transport unit 40 and the transport control unit 50 constituting the paper transport system of the multi-function device 1, and each part in the multi-function device 1 described in FIGS. This is schematically shown from the viewpoint of conveyance. Therefore, the same components as those described in FIGS.

  As shown in FIG. 3, the transport unit 40 of the multi-function device 1 includes a paper feed cassette 3, a paper feed unit 9 that separates and sends the paper P stored in the paper feed cassette 3 one by one, A transport roller 41 for transporting the paper P sent out by the paper feed roller 9 b of the paper feed unit 9 to the lower side of the recording head 15 and a pinch roller 42 disposed so as to face the transport roller 41 while being pressed against each other. And a paper discharge roller 43 that discharges the paper P after image formation to the paper discharge unit 21 while assisting paper conveyance during the image forming process, and a pinch that is opposed to the paper discharge roller 43 while being in pressure contact therewith. A roller (spur roller) 44, a bank portion 5 and a U-turn path 11 and a platen 19 that constitute a conveyance path of the paper P, an LF (Line Feed) motor 45 that is a drive source of the conveyance roller 41 and the paper discharge roller 43, Force generated by motor 45 Belts BL <b> 1 and BL <b> 2 for transmitting the motor 45 and a motor driving unit 82 that drives the motor 45 based on various commands (control signals) input from the ASIC 70.

  The upstream portion of the conveyance path composed of the bank portion 5 and the U-turn path 11 regulates the movement of the paper P sent out by the paper feed roller 9b, so that the paper P is brought into contact with the conveyance roller 41 and the pinch roller 42. For guiding, on the downstream side in the transport direction of the paper P in the U-turn path 11, the downward movement of the paper P is restricted below, and the paper P is transported to the transport roller 41 and the pinch roller 42. An auxiliary portion 11a for guiding to the contact is provided.

  Therefore, the paper P delivered from the paper feed cassette 3 is guided to the contact point between the transport roller 41 and the pinch roller 42 by the bank portion 5, the U-turn path 11, and the auxiliary portion 11a. In this state, when the transport roller 41 rotates forward in the transport direction (counterclockwise rotation in FIG. 3), the paper P is drawn between the transport roller 41 and the pinch roller 42 and is moved to the transport roller 41 and the pinch roller 42. It is pinched. Thereafter, the paper P is transported to the paper discharge roller 43 side, which is the transport direction, at a distance corresponding to the rotation amount of the transport roller 41 along with the rotation of the transport roller 41.

  On the other hand, the platen 19 constitutes a downstream portion of the conveyance path connecting the conveyance roller 41 and the discharge roller 43, and is provided between the conveyance roller 41 and the discharge roller 43 along a line connecting them. ing. The platen 19 guides the paper P sent from the conveying roller 41 to a region where an image is formed by the recording head 15, and the paper P on which the image is formed by the recording head 15 with the paper discharge roller 43. The contact is made with the pinch roller 44. Hereinafter, an end point on the downstream side of the image forming region RG where image formation is performed with ink of each color is expressed as an image forming point GP, and an upstream neighboring point of the upstream end point of the image forming region RG is a transport start point GS. It expresses.

The paper P is conveyed along the platen 19 toward the paper discharge roller 43, and when the front end (downstream edge) of the paper P reaches the contact point between the paper discharge roller 43 and the pinch roller 44, the paper discharge roller 43. Is rotated between the paper discharge roller 43 and the pinch roller 44 and is sandwiched between the paper discharge roller 43 and the pinch roller 44. Thereafter, along with the rotation of the paper discharge roller 43, the paper is transported to the paper discharge unit 21 side which is a distance corresponding to the rotation amount of the paper discharge roller 43 (matching the rotation amount of the transport roller 41). The transport roller 41, the paper discharge roller 43, and the pinch rollers 42 and 44 are rotating bodies having a rotation axis in a direction (main scanning direction) intersecting (orthogonal to) the transport direction. The sheet P receives a driving force from the contact point with the transport roller 41 and the contact point with the paper discharge roller 43 and is transported along the transport path in the transport direction (that is, from upstream to downstream of the transport path) as described above. .

  The motor 45 is constituted by a DC motor, and is driven by a motor driving unit 82. The rotation force of the motor 45 is conveyed via a belt BL1 spanned between the motor 45 and the conveyance roller 41. 41. Thereby, the conveyance roller 41 rotates. Further, the rotational force transmitted to the transport roller 41 is transmitted to the paper discharge roller 43 via the belt BL2 spanned between the transport roller 41 and the paper discharge roller 43, whereby the paper discharge roller 43 is It rotates in the same direction as the transport roller 41. In addition, the rotational force generated from the motor 45 is transmitted to the paper feed roller 9b via a transmission mechanism (not shown), whereby the paper feed roller 9b rotates.

  However, the paper feed roller 9b rotates in the transport direction of the paper P only during paper feed processing and sends the paper P to the transport roller 41 side, and idles without receiving the rotational force from the motor 45 during image formation processing. . That is, the transmission mechanism that connects the paper feed roller 9b and the motor 45 transmits the rotational force to the paper feed roller 9b only during paper feed, and separates the built-in gear during the image forming process, so that the rotational force is applied to the paper feed roller 9b. It is configured not to transmit.

  When the paper feed roller 9b rotates in the transport direction, the transport roller 41 and the paper discharge roller 43 rotate in the direction opposite to the transport direction. That is, the transmission mechanism connecting the paper feed roller 9b and the motor 45 does not transmit the rotational force to the paper feed roller 9b when the motor 45 rotates forward, and incorporates the rotational force when the motor 45 rotates reversely. The gear is converted into a rotational force in the positive direction by a gear and transmitted to the paper feed roller 9b.

  Here, the paper feed processing means that the paper feed roller 9b is rotated in a state where the paper feed roller 9b is pressed against the uppermost paper P among the papers P stacked on the paper feed cassette 3. The process of conveying the leading edge of the paper P to a registration position that is a contact point between the conveyance roller 41 and the pinch roller 42 is shown. The image forming process corresponds to the initial conveying process for conveying the leading end of the drawing area on the paper P placed at the registration position to the image forming point GP, and then the width of the image forming region RG in the conveying direction. At each interval, the reference point of the paper P located at the transport start point GS is sequentially transported to the image forming point GP, and ink is ejected from the recording head 15 in conjunction with the transport of the paper P, and an image is printed on the paper P. The process which consists of this process to form is shown. However, the reference point of the paper P here indicates a point of the paper P located at the transport start point GS at the start of transport. The reference point of the paper P changes as the paper P is fed.

  The transport unit 40 is provided with a rotary encoder 49 that outputs a pulse signal each time the transport roller 41 rotates by a predetermined amount. The output signal of the rotary encoder 49 is input to the ASIC 70 of the transport control unit 50. In the present embodiment, the transport roller 41 and the paper discharge roller 43 are rotated by a motor 45, and the rotation of the motor 45 is also transmitted to the paper feed roller 9b. For this reason, in the multi-function device 1, by detecting and counting the pulse signal from the encoder 49, the rotation amount of the motor 45, the transport roller 41, the paper discharge roller 43, and the paper feed roller 9b, the rollers 41, It is possible to detect the movement distance (conveyance distance) of the paper P conveyed by 43, 9b.

[Description of Transport Control Unit 50]
Next, the conveyance control unit 50 provided in the multi-function device 1 will be described. FIG. 4 is a block diagram illustrating the configuration of the transport control unit 50.

  The conveyance control unit 50 connected to the motor drive unit 82 of the conveyance unit 40 inputs a command for the motor 45 to the motor drive unit 82 to control the rotation of the motor 45 constituting the conveyance unit 40, indirectly. Control of paper conveyance by the paper feed roller 9b, the conveyance roller 41, and the paper discharge roller 43 is realized.

  As shown in FIG. 4, the conveyance control unit 50 includes an ASIC (Application Specific Integrated Circuit) that controls the rotation speed, rotation direction, and the like of the CPU 60, CPU 60, ROM 62, RAM 64, EEPROM 66, and motor 45 that collectively control the multifunction device 1. 70). The CPU 60, ROM 62, RAM 64, EEPROM 66 and ASIC 70 are connected by a bus 68. Note that the CPU 60 also has a function of performing overall control of the multi-function device 1.

  The conveyance control unit 50 includes a head driving unit 80 for driving the recording head 15 (ink ejection) and a motor driving unit 82 for driving the carriage motor 16 and the motor 45. The head driving unit 80 and the motor driving unit 82 are connected to the ASIC 70 and control driving of the recording head 15 (ink ejection), driving of the carriage motor 16 and the motor 45. The carriage 17 is driven in the main scanning direction by the rotation of the carriage motor 16.

  Further, the transport control unit 50 includes a panel interface unit 84 that processes a signal from the operation panel unit 29 and a USB interface unit 86 that is communicably connected to an external computer or the like.

  The ASIC 70 included in the conveyance control unit 50 detects the carriage encoder 18 that detects the main scanning amount (position) of the carriage 17, the paper conveyance encoder 49 that detects the conveyance amount (position) of the paper P, and the glossiness of the paper. The glossiness sensor 12 is electrically connected. Signals from the carriage encoder 18 and the paper transport encoder 49 are input to the ASIC 70.

  The RAM 64 stores an adjustment pattern (test pattern) illustrated in FIG. This adjustment pattern includes a first pattern (shown by a thick line in FIGS. 8A and 8B) printed using a downstream portion (see FIG. 8D) in the nozzle row of the recording head 15, and a recording. It consists of a second pattern (illustrated by thin lines in FIGS. 8 (a) and 8 (b)) printed using the upstream portion (see FIG. 8 (d)) of the nozzle row of the head 15, and each other is the first pattern. And the second pattern are composed of five symbol patterns that are slightly shifted (see FIGS. 8A and 8B). The adjustment pattern includes an adjustment pattern corresponding to the first half of the paper (contact pattern, see FIG. 8A), and an adjustment pattern corresponding to the second half of the paper (non-contact pattern, FIG. 8B). ))). Here, the contact test pattern is a test pattern for inspecting the condition of image recording by the recording head 15 by recording an image on a sheet conveyed by the conveying roller 41 while being in contact with the paper feed roller 9b. That is, it is printed on the first half of the paper being conveyed (see FIG. 6). This contact test pattern is corrected in advance so that the first pattern matches the second pattern in the third (center) symbol pattern from the left of the five symbol patterns when printed on the first half of the paper. (See FIG. 8A). The non-contact test pattern is a test for inspecting the condition of image recording by the recording head 15 by recording an image on a sheet conveyed by the conveying roller 41 without contacting the sheet feeding roller 9b. A pattern is printed on the latter half of the paper being conveyed (see FIG. 6). This non-contact test pattern is preliminarily set so that the first pattern matches the second pattern in the third (center) symbol pattern from the left among the five symbol patterns when printed on the second half of the paper. This is a corrected pattern (see FIG. 8B). Note that the reference correction values for correcting the carry amounts of the contact test pattern and the non-contact test pattern are different from each other.

  It should be noted that an adjustment pattern matching the first pattern and the second pattern is composed of the same pattern as the adjustment pattern (contact test pattern) corresponding to the first half of the sheet adjusted to the center position (FIG. 8 ( When a) is used as a non-contact test pattern, the amount transported by the transport roller 41 while being in contact with the paper feed roller 9b and transported by the transport roller 41 without being in contact with the paper feed roller 9b Since the amount is different, for example, the first pattern (illustrated by a thick line in FIG. 8C) and the second pattern (illustrated by a thin line in FIG. 8C) are the leftmost of the five symbol patterns. ) Match, and the center position of the adjustment pattern where the first pattern matches the second pattern is shifted (see FIG. 8C). Therefore, in this embodiment, the non-contact test pattern illustrated in FIG. 8B is used as an adjustment pattern corresponding to the second half of the paper.

  By preparing different adjustment patterns for the first half and the second half of the paper in this way, the adjustment pattern can be centered and the adjustment range can be expanded even if the same number of patterns are used. effective.

Further, the RAM 64 has a reference table (see FIG. 7A) and a calculation formula (see FIG. 7A) for calculating the correction amount of paper other than plain paper such as glossy paper from the correction amount of plain paper illustrated in FIG. FIG. 7B is stored. This reference table includes a numerical value “a” that is a correction amount for the first half portion of the paper, a numerical value “b” that is a correction amount for the second half portion of the paper, and a difference in the transport amount between plain paper and glossy paper in the first half portion of the paper. A certain numerical value “c” is associated with a numerical value “d” that is a difference in transport amount between plain paper and glossy paper in the second half of the paper (see FIG. 7A). The numerical values “a” and “b” described above are stored in the adjustment pattern automatic determination process described later, and the numerical values “c” and “d” are obtained by sampling inspection or the like. The measured numerical value is stored in advance.
When the paper being transported is glossy paper, the transport amount correction for glossy paper is corrected based on the following calculation formulas (1) and (2) stored in the RAM 64 with reference to the reference table described above. The amount is calculated (see FIG. 7B).

Correction amount of transport amount for the first half of glossy paper = numerical value “a” + numerical value “c” (1)
Correction amount of conveyance amount for the latter half of glossy paper = numerical value “b” + numerical value “d” (2)

In the present embodiment, the RAM 64 corresponds to a test pattern storage unit and a correction amount storage unit, and the CPU 60 corresponds to a control unit, a determination unit, a calculation unit, and a detection unit.

[Description of automatic adjustment pattern judgment processing]
Below, the adjustment pattern automatic determination process performed by CPU60 is demonstrated based on the flowchart of FIG. This automatic adjustment pattern determination process is executed when an instruction to print an adjustment pattern is issued via the operation panel unit 29 when the multi-function device 1 is activated.

  First, when an instruction to print the adjustment pattern is given, page printing is executed (S110). Specifically, the CPU 60 controls the paper feed roller 9 b to send out the paper P stored in the paper feed cassette 3, and controls the recording head 15, the carriage 17, and the transport roller 41 to move the carriage 17. In addition, a page printing process for recording an image on a sheet is performed by repeatedly performing ink ejection by the recording head 15 and intermittent conveyance by the conveyance roller 41. During this page printing, the adjustment pattern is printed on the paper being conveyed (S120). Specifically, when the paper is transported by the transport roller 41 while being in contact with the paper feed roller 9b, the CPU 60 reads the contact test pattern from the RAM 64 and images the read contact test pattern on the paper. Let me record. On the other hand, when the paper is transported by the transport roller 41 without contacting the paper feed roller 9b, the CPU 60 reads the non-contact test pattern from the RAM 64 and places the read non-contact test pattern on the paper. Record an image. When an adjustment pattern is printed on A4 size paper, at least the size of the recording head 15 is separated in the front-rear direction from the center line of the paper (the position where the rear portion of the paper in FIG. 6 is separated from the paper feed roller 41). Print.

  Subsequently, the adjustment pattern printed on the paper is read by the image reading device 23, the reference pattern is referred to, and the ID that minimizes the error between the read image and the reference pattern is extracted (S130). Then, the ID is extracted by specifying the adjustment pattern that minimizes the calculated error. That is, the appropriate degree of the test pattern at the time of contact recorded on the paper and the appropriate degree of the test pattern at the time of non-contact recorded on the paper are determined.

  Subsequently, the correction amount is calculated according to the previously extracted ID (S140). Specifically, the contact correction amount and the non-contact correction amount are calculated according to the appropriate degree determined by the determination unit. The contact correction amount is a correction amount for correcting the transport amount by the transport roller 41 when a standard type of paper (plain paper) is transported by the transport roller 41 while being in contact with the paper feed roller 9b. In other words, the non-contact correction amount corrects the transport amount by the transport roller 41 when a standard type of paper (plain paper) is transported by the transport roller 41 without contacting the paper feed roller 9b. This is the correction amount.

  Further, a correction amount corresponding to the paper type is calculated for each type (S150). Specifically, referring to the reference table illustrated in FIG. 7A, paper other than plain paper such as glossy paper is in contact with the paper feed roller 9b in accordance with the previously calculated contact correction amount. A correction amount at the time of contact (correction amount at the time of contact of other types) for correcting the transport amount by the transport roller 41 when transported by the transport roller 41 is calculated by the calculation formula illustrated in FIG. In order to correct the transport amount by the transport roller 41 when paper other than plain paper such as glossy paper is transported by the transport roller 41 without being in contact with the paper feed roller 9b, according to the calculated non-contact correction amount. The non-contact correction amount (other-type non-contact correction amount) is calculated by the calculation formula (1) and the calculation formula (2) illustrated in FIG. 7B.

  Subsequently, the previously calculated contact correction amount and non-contact correction amount are stored and set in the register (RAM 64) as conveyance correction values (S160). When the page printing process described above is subsequently executed, the CPU 60 detects the type of paper being conveyed based on the output signal from the glossiness sensor 12, and performs correction corresponding to the detected type of paper. When the amount is read from the register and the above-described page printing process is executed, the carry amount by the carry roller 41 is controlled based on the read correction amount. Then, this process ends.

[effect]
(1) As described above, according to the multi-function device 1 of the present embodiment, different adjustment patterns are printed depending on whether or not the paper feed roller 9b is in contact, and the appropriate degree of the adjustment pattern is determined. A correction amount for transporting plain paper is calculated, a correction amount for non-plain paper such as glossy paper is calculated from the calculated correction amount, and the transport amount by the transport roller 41 is controlled by the calculated correction amount. To do. As a result, the change in the paper conveyance deviation between the case where the rear portion of the paper is pressed by the paper supply roller 9b and the case where the paper is released from the pressure contact of the paper supply roller 9b is reduced. Changes in conveyance deviation can be reduced.

  Further, according to the multi-function device 1 of the present embodiment, when conveying other types of paper such as glossy paper, only by determining the degree of conformity of the test pattern to standard types of paper such as plain paper. In the same manner as in the case of transporting a standard type of paper such as plain paper, the rear part of the paper is pressed by the paper feed roller 9b and the paper is released from the pressure contact of the paper feed roller 9b. A change in conveyance deviation is small, and a change in conveyance deviation of the sheet depending on the type of sheet can be reduced. Therefore, the cost required for adjusting the multi-function device 1 at the time of manufacture can be reduced, and the manufacturing cost can be reduced.

  (2) Further, according to the multi-function device 1 of the present embodiment, the reference correction value for correcting the carry amount is different for the contact pattern and the non-contact pattern. As a result, in a plurality of patterns in the test pattern, appropriate patterns are arranged in the center for both the contact pattern and the non-contact pattern, so that the adjustment area can be expanded or the number of patterns can be reduced even with the same number of patterns. Can do.

  (3) Also, according to the multi-function device 1 of the present embodiment, the correction amount for correcting the transport amount by the transport roller 41 is calculated for each multi-function device 1. The conveyance roller 41 can be controlled with high accuracy based on the correction amount.

  (4) According to the multi-function device 1 of the present embodiment, in step S130 of the automatic adjustment pattern determination process, the adjustment pattern printed on the paper is read by the image reading device 23, and the reference pattern is referred to. An ID that minimizes the error between the read image and the reference pattern is extracted. As a result, it is possible to automatically determine the appropriateness of the adjustment pattern recorded on the paper. For example, an inspector or the like checks and inputs the appropriateness of the adjustment pattern recorded on the paper. Compared with the case where it receives, while reducing the burden of the inspector at the time of manufacture, a manufacturing man-hour can be reduced.

  (5) Also, according to the multi-function device 1 of the present embodiment, the image reading device 23 is placed on the paper at a resolution more than twice the adjustment pattern recorded on the paper by the recording head 15. The adjustment pattern recorded in the image can be read. Thus, the adjustment pattern recorded on the paper can be read well.

  (6) Further, according to the multi-function device 1 of the present embodiment, for the contact pattern and the non-contact pattern, the reference correction value for correcting the carry amount is made different, and the contact pattern and the non-contact pattern Are configured in substantially the same pattern. As a result, the pattern of the main scanning operation in which the recording head ejects ink can be shared, and the amount of memory used can be reduced.

[Other Embodiments]
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, It is possible to implement in the following various aspects.

  (1) In the above embodiment, the RAM 64 stores the adjustment pattern composed of the contact test pattern and the contact test pattern. In step S120 of the automatic adjustment pattern determination process, the sheet comes into contact with the paper feed roller 9b. However, when the sheet is conveyed by the conveying roller 41, the CPU 60 reads the contact test pattern from the RAM 64 and records the read contact test pattern on the sheet, while the sheet contacts the sheet feeding roller 9b. However, the CPU 60 reads the non-contact test pattern from the RAM 64 and records the read non-contact test pattern on the paper. However, the present invention is not limited to this. The amount of paper transport when the paper feed roller 9b does not contact the paper is stable. Paying attention to this, when a non-contact test pattern is printed at the time of non-contact with the paper feed roller 9b, a correction amount for transporting standard paper is calculated by determining an appropriate degree of the test pattern, and the calculation is performed. The correction amount at the time of contact with the paper feed roller 9b may be calculated from the corrected amount by using a reference table illustrated in FIG. 7C and a calculation formula illustrated in FIG.

This reference table includes a numerical value “a” that is a correction amount for the second half of the paper, a numerical value “b” that is a difference between the transport amount in the first half of the plain paper and the transport amount in the second half, and the plain paper in the second half of the paper. A numerical value “c” that is the difference in the conveyance amount with the glossy paper and a numerical value “d” that is the difference between the conveyance amount in the first half of the glossy paper and the conveyance amount in the second half of the glossy paper are associated (see FIG. 7C). ). Note that the numerical value calculated in the adjustment pattern automatic determination process is stored for the numerical value “a” described above, and the numerical values “b”, “c”, and “d” are measured by sampling inspection or the like. Stored in advance. When the paper being transported is plain paper, the correction amount of the transport amount for the second half of the plain paper is referred to the above reference table and based on the following calculation formula (3) stored in the RAM 64. Is calculated (see FIG. 7D).

Correction amount of transport amount for the first half of plain paper = numerical value “a” + numerical value “b” (3)

When the paper being transported is glossy paper, the transport amount correction for glossy paper is corrected based on the following calculation formulas (4) and (5) stored in the RAM 64 with reference to the reference table. The amount is calculated (see FIG. 7D).

Correction amount of transport amount for the first half of glossy paper = numerical value “a” + numerical value “c” + numerical value “d”
... Formula (4)
Correction amount of conveyance amount for the latter half of glossy paper = numerical value “a” + numerical value “c” (5)

In this way, an adjustment pattern consisting of a single test pattern may be recorded on a sheet of paper, so that an appropriate degree of the test pattern can be compared with the case where an adjustment pattern consisting of a plurality of test patterns is recorded on a sheet of paper. Can be reduced. Therefore, the cost required for adjusting the multi-function device 1 at the time of manufacture can be reduced, and the manufacturing cost can be reduced.

  (2) In the above embodiment, in step S130 of the automatic adjustment pattern determination process, the adjustment pattern printed on the paper is read by the image reading device 23, the reference pattern is referred to, and the error between the read image and the reference pattern By extracting the ID that minimizes the image quality, the appropriate degree of the adjustment pattern recorded on the paper is automatically determined. However, the present invention is not limited to this. May confirm the appropriate degree, and the CPU 60 may determine the appropriate degree based on the confirmation result.

[Description of Adjustment Pattern Visual Judgment Processing]
Below, the adjustment pattern visual determination process performed by CPU60 is demonstrated based on the flowchart of FIG. This adjustment pattern visual determination process is executed when an instruction to print the adjustment pattern is issued via the operation panel unit 29 when the multi-function device 1 is activated.

  First, when an instruction to print the adjustment pattern is issued, page printing is executed (S210). Specifically, the CPU 60 controls the paper feed roller 9 b to send out the paper P stored in the paper feed cassette 3, and controls the recording head 15, the carriage 17, and the transport roller 41 to move the carriage 17. In addition, a printing process for recording an image on a sheet is performed by repeatedly performing ink ejection by the recording head 15 and intermittent conveyance by the conveyance roller 41. During this page printing, the adjustment pattern is printed on the paper being conveyed (S220). Specifically, the CPU 60 reads the contact test pattern from the RAM 64 in the portion where the sheet is conveyed by the conveyance roller 41 while being in contact with the paper feed roller 9b, and the read contact test pattern is imaged on the sheet. Let me record. On the other hand, the CPU 60 reads the non-contact test pattern from the RAM 64 in a portion where the paper is transported by the transport roller 41 without contacting the paper feed roller 9b, and the read non-contact test pattern is placed on the paper. Record an image.

Subsequently, an ID input from the operation panel unit 29 by an inspector who has confirmed the adjustment pattern printed on the sheet is received (S230).
Subsequently, according to the received ID, a contact correction amount and a non-contact correction amount are calculated (S240).

  Further, a correction amount corresponding to the paper type is calculated for each type (S250). Specifically, according to the previously calculated contact correction amount, when paper other than plain paper such as glossy paper is transported by the transport roller 41 while in contact with the paper feed roller 9b, A contact correction amount for correcting the carry amount is calculated, and paper other than plain paper such as glossy paper is conveyed without contacting the paper feed roller 9b according to the previously calculated non-contact correction amount. When the sheet is conveyed by the roller 41, a non-contact correction amount for correcting the sheet conveyance amount by the conveyance roller 41 is calculated.

  Subsequently, the previously calculated contact correction amount and non-contact correction amount are stored and set in the register (RAM 64) as conveyance correction values (S260). When the page printing process described above is subsequently executed, the CPU 60 detects the type of paper being conveyed based on the output signal from the glossiness sensor 12, and performs correction corresponding to the detected type of paper. When the amount is read from the register and the above-described page printing process is executed, the conveyance amount of the sheet by the conveyance roller 41 is controlled based on the read correction amount. Then, this process ends.

  The operation panel unit 29 and the CPU 60 correspond to input means.

1 is a perspective view of a multi-function device 1 to which an image forming system of the present invention is applied. 2 is a side sectional view of the multi-function device 1. FIG. It is explanatory drawing of the conveyance part 40 and the conveyance control part 50 which comprise a conveyance system. 3 is a block diagram illustrating a configuration of a conveyance control unit 50. FIG. It is a flowchart which shows the adjustment pattern automatic determination process performed by CPU60. It is explanatory drawing which shows an adjustment pattern. It is explanatory drawing (1) explaining an adjustment pattern automatic determination process. It is explanatory drawing (2) explaining an adjustment pattern automatic determination process. It is a flowchart which shows the adjustment pattern visual determination process performed by CPU60.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Multifunctional device, 2 ... Housing, 2a ... Opening part, 3 ... Paper feed cassette,
3a ... auxiliary support member, 3b ... storage part, 5 ... bank part, 7 ... box-type main frame,
9 ... Paper feed section, 9a ... Paper feed arm, 9b ... Paper feed roller, 11 ... U-turn path,
11a ... auxiliary unit, 12 ... glossiness sensor, 13 ... image forming unit, 15 ... recording head,
16 ... Carriage motor, 17 ... Carriage, 18 ... Carriage encoder,
DESCRIPTION OF SYMBOLS 19 ... Platen, 21 ... Paper discharge part, 21a ... Paper discharge port, 23 ... Image reader,
23a ... bottom wall, 23b ... pivot, 25 ... upper cover body, 27 ... document cover body,
29 ... Operation panel, 31 ... Mounting glass plate, 35 ... Guide shaft,
37 ... Ink supply pipe, 40 ... Conveying section, 41 ... Conveying roller, 42 ... Pinch roller,
43 ... discharge roller, 44 ... pinch roller, 45 ... motor, 49 ... paper transport encoder,
50 ... Transport control unit, 68 ... Bus, 80 ... Head drive unit, 82 ... Motor drive unit,
84 ... Panel interface unit 86 ... USB interface unit

Claims (12)

A recording head capable of selectively ejecting ink toward the paper;
A carriage mounted with the recording head and reciprocating in a predetermined direction;
A paper feed tray capable of storing a plurality of the sheets;
A paper feed roller for separating and sending out the paper stored in the paper feed tray one by one;
A transport roller that intermittently transports the paper fed from the paper feed tray by the paper feed roller in a direction substantially perpendicular to the predetermined direction when the recording head is not discharging ink;
The paper feed roller is controlled to feed the paper stored in the paper feed tray, and the recording head, the carriage, and the transport roller are controlled to move the carriage and ink by the recording head. Control means for executing a printing process for recording an image on the paper by repeatedly performing discharge and intermittent conveyance by the conveyance roller;
An inkjet recording apparatus comprising:
What is a contact test pattern for inspecting the condition of image recording by the recording head by recording an image on the sheet conveyed by the conveying roller while being in contact with the sheet feeding roller, and the sheet feeding roller? A test pattern storage means for storing a non-contact test pattern for inspecting the condition of image recording by the recording head by recording an image on the paper transported by the transport roller without contact;
The control unit reads the contact test pattern from the test pattern storage unit when the sheet is conveyed by the conveyance roller while being in contact with the sheet feeding roller, and the recording head, the carriage, and the conveyance roller The contact test pattern read out is recorded on the sheet, and when the sheet is conveyed by the conveyance roller without contacting the sheet feeding roller, the non-contact test pattern is recorded. Read from the test pattern storage means, control the recording head, the carriage and the transport roller to record the read non-contact test pattern on the paper,
Determination means for respectively determining an appropriate degree of the test pattern at the time of contact recorded on the paper and an appropriate degree of the test pattern at the time of non-contact recorded on the paper;
In accordance with the appropriate degree determined by the determination means, the correction amount at the time of correcting when the sheet is conveyed by the conveying roller while being in contact with the sheet feeding roller, and the sheet is the sheet feeding A calculation means for calculating a non-contact correction amount for correcting a conveyance amount when the conveyance roller conveys without contacting the roller;
Correction amount storage means for storing the correction amount calculated by the calculation means,
The inkjet recording apparatus, wherein the control unit reads the correction amount from the correction amount storage unit, and controls the transport unit based on the read correction amount when executing the printing process. The inkjet recording apparatus according to claim 1, wherein
Detecting means for detecting the type of the paper;
The calculating means calculates a correction amount at the time of the contact of another type for correcting a transport amount when a paper of a type other than the standard type is transported by the transport roller while being in contact with the paper feed roller. Other types of non-contact for correcting the conveyance amount when a paper of a type other than the standard type is conveyed by the conveyance roller without being in contact with the paper feed roller, while being calculated based on the correction amount A time correction amount is calculated based on the non-contact correction amount,
The correction amount storage means stores the correction amount calculated by the calculation means,
The control unit reads out the correction amount corresponding to the paper type detected by the detection unit from the correction amount storage unit, and executes the printing process when the printing unit executes the printing process. An ink jet recording apparatus characterized by controlling. The inkjet recording apparatus according to claim 1 or 2,
Input means for inputting information indicating an appropriate degree of the test pattern at the time of contact recorded on the paper and an appropriate degree of the test pattern at the time of non-contact recorded on the paper;
The determination unit is configured to record the contact test pattern recorded on the sheet according to information indicating the appropriate degree of the contact test pattern and the non-contact test pattern input by the input unit. And an appropriate degree of the non-contact test pattern recorded on the sheet, respectively. The inkjet recording apparatus according to claim 1 or 2,
A criterion storage means for storing criterion for determining an appropriate degree of the test pattern at the time of contact recorded on the paper and the test pattern at the time of non-contact recorded on the paper;
Reading means for reading the contact test pattern recorded on the paper and the non-contact test pattern recorded on the paper;
With
The determination unit refers to the determination criterion stored in the determination criterion storage unit and determines the appropriate degree of the contact test pattern and the non-contact test pattern read from the paper by the reading unit. An ink jet recording apparatus characterized by determining each. The inkjet recording apparatus according to claim 4, wherein
The reading means records the test pattern on contact recorded on the paper and the image on the paper at a resolution more than twice the test pattern recorded on the paper by the recording head. An inkjet recording apparatus capable of reading the non-contact test pattern. In the ink jet recording apparatus according to any one of claims 1 to 5,
The ink jet recording apparatus, wherein the contact correction pattern and the non-contact pattern recorded on the paper have different reference correction values for correcting the conveyance amount. In the ink jet recording apparatus according to any one of claims 1 to 6,
The inkjet recording apparatus, wherein the contact pattern and the non-contact pattern recorded on the paper are substantially the same pattern. A recording head capable of selectively ejecting ink toward the paper;
A carriage mounted with the recording head and reciprocating in a predetermined direction;
A paper feed tray capable of storing a plurality of the sheets;
A paper feed roller for separating and sending out the paper stored in the paper feed tray one by one;
A transport roller that intermittently transports the paper fed from the paper feed tray by the paper feed roller in a direction substantially perpendicular to the predetermined direction when the recording head is not discharging ink;
The paper feed roller is controlled to feed the paper stored in the paper feed tray, and the recording head, the carriage, and the transport roller are controlled to move the carriage and ink by the recording head. Control means for executing a printing process for recording an image on the paper by repeatedly performing discharge and intermittent conveyance by the conveyance roller;
An inkjet recording apparatus comprising:
A test pattern for storing a non-contact test pattern for inspecting the condition of image recording by the recording head by recording an image on the sheet conveyed by the conveying roller without contacting the sheet feeding roller A storage means,
The control means reads the non-contact test pattern from the test pattern storage means when the paper is transported by the transport roller without being in contact with the paper feed roller, the recording head, the carriage, The non-contact test pattern read out by controlling the transport roller is recorded on the paper,
Determining means for respectively determining the appropriate degree of the non-contact test pattern recorded on the paper;
In accordance with the appropriate degree determined by the determination unit, a non-contact correction amount for correcting the transport amount when the sheet is transported by the transport roller without being in contact with the paper feed roller, Calculating means for calculating a contact correction amount for correcting a transport amount when the paper is transported by the transport roller while being in contact with the paper feed roller based on the calculated non-contact correction amount;
Correction amount storage means for storing the correction amount calculated by the calculation means,
The inkjet recording apparatus, wherein the control unit reads the correction amount from the correction amount storage unit, and controls the transport unit based on the read correction amount when executing the printing process. In the ink jet recording apparatus according to claim 8,
Detecting means for detecting the type of the paper;
The calculation means corrects a correction amount at the time of contact of another type for correcting a transport amount when a paper of a type other than a standard type is transported by the transport roller while being in contact with the paper feed roller. A non-contact correction for correcting the transport amount when a paper of a type other than the standard type is transported by the transport roller without being in contact with the paper feed roller. Calculating the amount based on the non-contact correction amount,
The correction amount storage means stores the correction amount calculated by the calculation means,
The control unit reads out the correction amount corresponding to the paper type detected by the detection unit from the correction amount storage unit, and executes the printing process when the printing unit executes the printing process. An ink jet recording apparatus characterized by controlling. In the ink jet recording apparatus according to claim 8 or 9,
Input means for inputting information indicating the appropriate degree of the non-contact test pattern recorded on the paper;
The determination unit determines an appropriate degree of the non-contact test pattern recorded on the paper according to information indicating an appropriate degree of the non-contact test pattern, respectively. . In the ink jet recording apparatus according to claim 8 or 9,
A criterion storage unit for storing a criterion for determining an appropriate degree of the non-contact test pattern recorded on the paper;
Reading means for reading the non-contact test pattern image recorded on the paper,
The determination unit refers to the determination criterion stored in the determination criterion storage unit, and determines an appropriate degree of the non-contact test pattern read from the sheet by the reading unit. apparatus. The inkjet recording apparatus according to claim 11, wherein
The reading means is capable of reading the non-contact test pattern recorded on the paper at a resolution more than twice the test pattern recorded on the paper by the recording head. An ink jet recording apparatus.