JP5970840B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an inkjet recording apparatus that records an image on a sheet by ejecting ink droplets toward the sheet.

  In an inkjet recording apparatus, when an image is recorded on a sheet, various positions on the sheet can be used as a reference. For example, in an inkjet recording apparatus, an image can be recorded on a sheet by centering with the center in the left-right direction of the sheet as a reference in addition to the most common left justification with the left end of the sheet as a reference.

  However, when recording an image on a sheet by centering, if the size of the sheet specified by the user is different from the size of the sheet that is actually conveyed in the inkjet recording apparatus and ejects ink droplets, the image Is not recorded in the center of the sheet, that is, the centering is not performed properly.

  Therefore, in the information processing apparatus described in Patent Document 1, the length in the main scanning direction (width direction orthogonal to the conveyance direction) of the sheet conveyed in the conveyance direction along the conveyance path is based on the output of the optical sensor. Is calculated. This will be described in detail below. The optical sensor is mounted on a main scanning feed mechanism that reciprocates the carriage. The sheet is stopped at a position facing the optical sensor, and the carriage is moved in this state. Thereby, the right edge and the left edge of the sheet are detected by the optical sensor. The control circuit of the information processing apparatus calculates the length of the sheet in the main scanning direction based on the detected position information of the right end and the left end of the sheet.

  By the way, in many known inkjet recording apparatuses, a rectangular sheet is conveyed such that its longitudinal direction is along the conveying direction, the short direction is the main scanning direction (horizontal direction), and the longitudinal direction is the sub-scanning direction (vertical direction). An image is recorded so that In such an ink jet recording apparatus (hereinafter also referred to as a “sheet vertical placement type apparatus”), centering is performed with reference to the short direction of the sheet.

  In the vertical sheet type apparatus, when centering is performed, the length of the sheet in the short direction can be calculated by moving the carriage as described above.

JP 2005-18356 A

  In recent years, an inkjet recording apparatus (hereinafter, also referred to as a sheet horizontal type apparatus) in which the vertical and horizontal directions of a conveyed sheet are opposite to those of a sheet vertical type apparatus is becoming common. In the lateral sheet type apparatus, a rectangular sheet is conveyed such that the short direction is along the conveying direction, the longitudinal direction is the main scanning direction (horizontal direction), and the short direction is the sub-scanning direction (vertical direction). Thus, an image is recorded.

  However, in the horizontal seat type apparatus, as in the vertical sheet type apparatus, centering is performed based on the short direction of the sheet. Therefore, in the lateral sheet type apparatus, the length of the sheet in the short direction cannot be calculated even if the carriage is moved. Therefore, in the lateral sheet type apparatus, when centering is performed, the length of the sheet in the short direction is calculated by conveying the sheet with the sheet facing the optical sensor.

  In the vertical sheet type apparatus, when two pages of images are recorded on one sheet, centering is performed based on the longitudinal direction of the sheet. Here, in the sheet vertical type apparatus, the length of the sheet in the longitudinal direction cannot be calculated even if the carriage is moved. Therefore, in such a case, when performing the centering, the sheet vertical type apparatus calculates the length in the longitudinal direction of the sheet by transporting the sheet in a state where the sheet and the optical sensor face each other.

  However, when the sheet is conveyed and the short or long length of the sheet is calculated, when the trailing edge of the sheet conveyance direction is detected by the optical sensor, the leading end portion of the sheet conveyance direction causes the recording head to There is a risk of passing. In other words, when the short or long length of the conveyed sheet becomes clear, there is a possibility that at least a part of the image recording on the sheet has been completed.

  As described above, in the information processing apparatus described in Patent Document 1, when the information processing apparatus is a sheet horizontal apparatus, or when the information processing apparatus is a sheet vertical apparatus, two pages of images are displayed. In the case of recording an image on a single sheet, the above-described problem (problem that centering is not properly executed) cannot be solved.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide means capable of appropriately centering a sheet in an apparatus that performs centering based on the sheet conveyance direction.

  (1) The inkjet recording apparatus of the present invention supports a tray on which a sheet is placed, a conveyance unit that conveys the sheet placed on the tray along a conveyance path, and a sheet that is conveyed on the conveyance path. A platen, a recording unit that is provided opposite to the platen, and that records an image on a sheet supported by the platen by ejecting ink droplets toward the platen, and a sheet conveyed through the conveyance path Based on the detection result by the sheet end detection unit and the sheet end detection unit that detects the downstream end and the upstream end in the conveyance direction, the first length in the conveyance direction of the sheet conveyed on the conveyance path is calculated. A calculating unit; a storage unit storing the first length calculated by the calculating unit; image data recorded on the sheet; and an upper image of the image recorded on the sheet based on the image data. Based on the acquisition means for acquiring the second length in the conveying direction, the image data and the second length acquired by the acquisition means, and the first length of the sheet stored in the storage unit, the second length Centering control means for controlling the recording unit and the conveying unit so as to form an image on the sheet whose center matches the center of the first length.

  In this configuration, sheet centering is executed on the assumption that the length in the conveyance direction of a sheet on which an image is to be recorded is the first length of a sheet on which an image has been recorded in the past. Thus, when the sheet on which an image is to be recorded is centered, it is not necessary to detect the sheet by the sheet edge detection unit. That is, in this configuration, it is possible to prevent the leading end in the sheet conveyance direction from passing through the recording unit before the length in the sheet conveyance direction is calculated.

  (2) The tray is placed so that the long side of the rectangular sheet can be conveyed as the downstream end and the upstream end in the conveying direction.

  In the ink jet recording apparatus having such a configuration, when an image for one page is recorded on one sheet, centering is executed with reference to the side along the sheet conveyance direction, that is, the short side of the sheet. Therefore, this structure is a suitable structure for producing the effect (1).

  (3) The tray is moved between a first position where the sheet can be conveyed to the conveyance path and a second position where the sheet cannot be conveyed. The inkjet recording apparatus of the present invention includes a tray detection unit that detects whether or not the tray is positioned at the first position, and after the image recording on the sheet that has been transported from the tray, the tray detection unit Position change storage control means for storing position change information indicating the position change of the tray in the storage unit on condition that the detection result of the tray has changed from the detection state to the non-detection state. When the position change information is stored in the storage unit, the calculating unit is configured to determine a first length in the transport direction of the sheet transported on the transport path based on a detection result by the sheet end detection unit. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus calculates the above.

  When the tray is moved from the first position to the second position after image recording on the most recent sheet, there is a possibility that a sheet having a size different from that of the sheet is placed on the tray. That is, there is a possibility that the sheet on which an image is recorded from now on and the sheet on which an image has been recorded most recently have different sizes. In such a case, the centering control means cannot properly perform centering. Therefore, in this configuration, the calculation means calculates the first length in the above case. Thereby, in this structure, even if it is a case where the sheet | seat mounted in a tray is replaced | exchanged, it becomes possible to show | play the effect similar to (1) again.

  (4) The inkjet recording apparatus of the present invention includes a sheet presence / absence detection unit that detects the presence / absence of a sheet placed on the tray, and the sheet presence / absence detection unit after image recording is performed on the sheet that is transported most recently from the tray. A state change storage control means for storing sheet state change information indicating a change in the presence or absence of a sheet in the tray in the storage unit on the condition that the detection result of the tray by the state has changed from a sheet absence state to a sheet presence state; Is further provided. When the sheet state change information is stored in the storage unit, the calculation unit is configured to determine a first length in the conveyance direction of the sheet conveyed on the conveyance path based on a detection result by the sheet end detection unit. Is calculated.

  When the detection result by the sheet presence / absence detection unit changes from the no sheet state to the present state after image recording for the most recent sheet, that is, when a sheet is newly placed on the tray after image recording for the most recent sheet, There is a possibility that a sheet having a different size from the sheet is placed. That is, there is a possibility that the sheet on which an image is recorded from now on and the sheet on which the image has been recorded most recently have different sizes. In such a case, the centering control means cannot properly perform centering. Therefore, in this configuration, the calculation means calculates the first length in the above case. Thereby, in this structure, even if it is a case where the sheet | seat mounted in a tray is replaced | exchanged, it becomes possible to show | play the effect similar to (1) again.

  (5) The storage unit stores a third length of the sheet specified by the user in the conveyance direction. The centering control unit is executed on condition that the difference between the first length and the third length stored in the storage unit is equal to or greater than a preset length threshold.

  In this configuration, the third length is a length in the sheet conveyance direction, and is specified by the user and stored in the storage unit. And according to this structure, even if it is a case where the length of the conveyance direction of the sheet | seat actually conveyed in a conveyance path is 1st length contrary to 3rd length memorize | stored in the memory | storage part. By executing the processing of the centering control means, it is possible to appropriately execute the centering of the sheet.

  (6) The centering control means may be arranged on the condition that the second length acquired by the acquisition means is longer than the first length stored in the storage unit, than the upstream end of the sheet in the conveyance direction. The recording unit is controlled so that ink droplets are not ejected based on image data corresponding to an image recorded on the upstream side.

  In this configuration, it is possible to prevent ink droplets from being ejected to an area where no sheet exists, that is, ink droplets from being ejected to the platen. Accordingly, it is possible to prevent the sheet conveyed next on the platen from being soiled by ink droplets attached to the platen. In addition, it is possible to prevent ejection of excess ink droplets.

  (7) The centering control unit may be configured so that the second length acquired by the acquiring unit is longer than the first length stored in the storage unit, and the downstream end of the sheet in the transport direction The recording unit is controlled so as not to eject ink droplets based on image data corresponding to an image recorded on the downstream side.

  In this configuration, the same effect as in (6) can be achieved.

  (8) The ink jet recording apparatus of the present invention is based on the image data acquired by the acquisition unit, the second length, and the detection result by the sheet end detection unit, and the upstream of the conveyance direction of the image recorded on the sheet. Further, upper end alignment control means for discharging ink droplets to the recording unit is further provided so that the difference between the position of the end and the position of the upstream end of the sheet in the conveyance direction is equal to or less than a preset position threshold value. The upper end alignment control unit is executed on condition that the second length acquired by the acquisition unit is longer than the first length stored in the storage unit. The center alignment control means is executed on condition that the second length acquired by the acquisition means is equal to or less than the first length stored in the storage unit.

  In this configuration, when there is a possibility that an ink droplet is ejected to an area where no sheet exists, the upper end alignment control unit is executed, whereby the possibility of the ink droplet adhering to the platen can be reduced. On the other hand, when there is no possibility that ink droplets are ejected to an area where no sheet exists, the centering control unit is executed, whereby the sheet can be properly centered.

  (9) The upper end alignment control unit controls the recording unit so as not to eject ink droplets based on image data corresponding to an image recorded on the downstream side of the downstream end of the sheet in the conveyance direction.

  In this configuration, the same effects as (6) and (7) can be obtained.

  (10) The inkjet recording apparatus of the present invention includes a manual tray on which a sheet is placed, a manual sheet presence / absence detecting unit that detects the presence / absence of a sheet placed on the manual tray, and the manual feeding by the manual sheet presence / absence detecting unit. And a first length storage control unit that does not store the first length calculated by the calculation unit in the storage unit on condition that the detection result of the tray is in the detection state. The said conveyance part conveys the sheet | seat mounted in the said manual feed tray along a conveyance path. The storage unit stores a third length in the transport direction of the sheet designated by the user. The centering control unit is stored in the storage unit and the image data and the second length acquired by the acquisition unit on condition that the detection result of the manual tray by the manual sheet presence / absence detection unit is in a detection state. Based on the third length, the recording unit and the conveyance unit are controlled so that an image in which the center of the second length coincides with the center of the third length is formed on the sheet.

  Usually, in the ink jet recording apparatus, when it is designated that paper is fed from the manual feed tray, the sheet is placed on the manual feed tray. In other words, when a sheet is fed from the manual feed tray, it is unlikely that the sheet on which an image is to be recorded and the sheet on which an image has been recorded most recently have the same size. Therefore, it is less necessary to store the first length in the storage unit. Since the ink jet recording apparatus having this configuration includes the first length storage control unit, it is possible to make the storage in the storage unit having the first length that is less necessary as described above non-executable.

  (11) The centering control means may be configured such that the center of the second length is the second length acquired on the condition that the second length acquired by the acquiring means is shorter than the first length stored in the storage unit. A margin amount on the downstream side in the conveyance direction of the sheet is calculated so as to coincide with the center of the first length, and the upstream side in the conveyance direction by the margin amount from the downstream end in the conveyance direction of the sheet is the head of the image. As described above, an image may be recorded in the recording unit.

  (12) The centering control means may be configured such that the center of the second length is the second length acquired on the condition that the second length acquired by the acquiring means is longer than the first length stored in the storage unit. When the image is recorded on the sheet so as to coincide with the center of the first length, the amount of protrusion of the image from the downstream end in the conveyance direction of the sheet is calculated, and the ink is based on the image data corresponding to the amount of protrusion. The recording unit may be controlled so as not to eject droplets.

  In the present invention, when centering is performed based on the sheet conveyance direction, the sheet can be appropriately centered.

FIG. 1 is a perspective view showing an external configuration of the multifunction machine 1. FIG. 2 is a longitudinal sectional view schematically showing the main configuration of the printer unit 2. FIG. 3 is a block diagram illustrating a configuration of the control unit 130. FIG. 4 is a flowchart for explaining image recording control of bordered printing. FIG. 5 is a flowchart for explaining image recording control for borderless printing. FIG. 6 is a plan view schematically showing a state in which the image 34 is recorded on the recording paper 19 in the conveyance path 23 below the recording unit 24. FIG. 7 is a plan view schematically showing a state in which the image 34 is recorded on the recording paper 19 in the conveyance path 23 below the recording unit 24. FIG. 8 is a flowchart for explaining the image recording control in the first modification. FIG. 9 is a flowchart for explaining the image recording control in the second modification. FIG. 10A is a flowchart for explaining the storage of the position change information, and FIG. 10B is a flowchart for explaining the storage of the sheet state change information.

  Hereinafter, an MFP 1 according to an embodiment of the present invention will be described with reference to the drawings as appropriate. In addition, embodiment is only an example of this invention, and it cannot be overemphasized that embodiment can be changed suitably in the range which does not change the summary of this invention. Further, in the following description, the progress from the starting point of the arrow to the ending point is expressed as “direction”, and the traffic on the line connecting the starting point and the ending point of the arrow is expressed as “direction”. In the following description, the vertical direction 7 is defined with reference to the state in which the multifunction machine 1 is installed (the state shown in FIG. 1), and the side on which the opening 6 is provided is the front side (front side). A front-rear direction 8 is defined, and a left-right direction 9 is defined when the multifunction device 1 is viewed from the front side (front side).

[Appearance of MFP 1]
As shown in FIG. 1, the multifunction machine 1 is formed in a substantially rectangular parallelepiped. The multifunction device 1 includes a printer unit 2 (an example of the ink jet recording apparatus of the present invention) disposed at the lower portion of the multifunction device 1 and a scanner unit 3 disposed at the upper portion. The multifunction device 1 has a print function, a scan function, a copy function, and the like. Functions other than the print function are arbitrary.

  The printer unit 2 records an image on a recording sheet 19 (an example of the sheet of the present invention, see FIG. 2) based on image data (an example of the image data of the present invention) transmitted from an external information device such as a computer. . A paper feed tray 20 (an example of the tray of the present invention) that can be inserted into and removed from the printer unit 2 and a paper discharge tray 21 are provided in two upper and lower stages inside an opening 6 formed in the front of the printer unit 2. . The scanner unit 3 is configured as a so-called flat bed scanner. Detailed description of the scanner unit 3 is omitted.

  An operation panel 4 (an example of the operation unit of the present invention) for operating the printer unit 2 and the scanner unit 3 is provided on the upper surface on the front side of the scanner unit 3. The operation panel 4 includes various operation buttons 10 and a liquid crystal display unit 11.

[Paper Tray 20]
As shown in FIG. 2, the paper feed tray 20 is disposed below the recording unit 24 described later when inserted in the printer unit 2. The paper feed tray 20 is generally formed in a box shape whose upper rear side is open. The upper front side of the paper feed tray 20 is covered with a paper discharge tray 21. That is, the paper discharge tray 21 is a part of the paper feed tray 20. A recording sheet 19 is placed on the sheet feeding tray 20.

  When the paper feed tray 20 is inserted into the printer unit 2, the paper feed tray 20 is located at a first position, which is a position indicated by a solid line in FIG. At this time, a paper feed unit 30 described later can feed the recording paper 19 placed on the paper feed tray 20 to a transport path 23 described later.

  On the other hand, when the paper feed tray 20 is located at the second position which is the front side of the first position, for example, when the paper feed tray 20 is removed from the printer unit 11, the paper feed unit 15 The recording paper 19 placed on the tray 20 cannot be fed to the transport path 23. As described above, the paper feed tray 20 is moved between the first position and the second position along the front-rear direction 8.

  In the present embodiment, the recording paper 19 accommodated in the paper feed tray 20 is rectangular. In the paper feed tray 20, the recording paper 19 is accommodated in a horizontally placed state with the short sides as the front and rear ends in the front-rear direction 12, that is, when viewed from the front of the multifunction machine 1. In other words, the recording paper 19 is held in the paper feed tray 20 so that the long side can be transported as a downstream end and an upstream end in a transport direction 15 (see FIG. 2) described later.

[First sensor 110]
As shown in FIG. 2, a first sensor 110 is provided on the rear side of the paper discharge tray 21. The first sensor 110 includes a shaft 111, a detector 112 rotatable about the shaft 111, a light emitting element (for example, a light emitting diode), and a light receiving element (for example, a phototransistor) that receives light emitted from the light emitting element. ) And an optical sensor 113 such as a photo interrupter.

  When the paper feed tray 20 is removed from the printer unit 2, the detector 112 maintains the position indicated by the wavy line in FIG. At this time, the detector 112 deviates from the optical path from the light emitting element to the light receiving element of the optical sensor 113, and light passes through the optical path. This state is a non-detection state of the paper feed tray 20. On the other hand, when the paper feed tray 20 is attached to the printer unit 2, the first detector 112 is rotated upward by being pushed by the protrusion 114 protruding from the rear end of the paper discharge tray 21. At this time, the detector 112 enters the optical path and blocks light passing through the optical path. This state is a detection state of the paper feed tray 20. The optical sensor 113 outputs a signal according to whether light is blocked or not to the control unit 130 described later. That is, the control unit 130 detects whether or not the paper feed tray 20 is located at the first position based on the signal from the optical sensor 113. As mentioned above, the tray detection part of this invention is comprised from the 1st sensor 110 and the control part 130. FIG.

[Paper Feeder 30]
As shown in FIG. 2, a paper feed unit 30 is provided above the paper feed tray 20. The paper feed unit 30 includes a paper feed roller 25 (an example of a transport unit of the present invention), a paper feed arm 26, a drive transmission mechanism 27, and a shaft 28. The paper feed roller 25 is pivotally supported on the paper feed tray 20 at the front end of the paper feed arm 26 that rotates in the direction of the arrow 22 about the shaft 28. The paper feed roller 25 is rotated by the driving force of the paper feed motor 76 (see FIG. 3) being transmitted through a drive transmission mechanism 27 having a plurality of gears. The paper feed roller 25 transports the recording paper 19 placed on the paper feed tray 20 in the transport direction 15. Here, the conveyance direction 15 is the direction indicated by the wavy arrow in FIG.

[Conveyance path 23]
As shown in FIG. 2, a conveyance path 23 extends from the rear end portion of the paper feed tray 20. The conveyance path 23 includes a curved portion and a straight portion. The recording paper 19 accommodated in the paper feed tray 20 is conveyed by the paper feed roller 25 and a conveyance roller pair 89 described later along the conveyance path 23 so as to make a U-turn from the lower side to the upper side. Are conveyed to the recording unit 24, where image recording is performed by the recording unit 24, and then the sheet is discharged onto the paper discharge tray 21.

[Conveying roller pair 89 and paper discharge roller pair 92]
As shown in FIG. 2, a conveyance roller pair 89 (an example of the conveyance unit of the present invention) including a conveyance roller 87 and a pinch roller 88 is provided in the conveyance path 23 on the rear side of the recording unit 24. A paper discharge roller pair 92 (an example of the conveyance unit of the present invention) including a paper discharge roller 90 and a spur 91 is provided in the conveyance path 23 in front of the recording unit 24. The recording paper 19 is transported onto a platen 42 (to be described later) by a transport roller pair 89 along a transport direction 15 along a broken line arrow in FIG. The recording paper 19 transported onto the platen 42 is transported to the paper discharge tray 21 by the paper discharge roller pair 92. The transport roller 87 and the paper discharge roller 90 are rotated by the driving force of the transport motor 59 (see FIG. 3) being transmitted through a drive transmission mechanism (not shown).

[Second sensor 120]
A second sensor 120 is provided on the upstream side of the transport direction 15 with respect to the transport roller pair 89 in the transport path 23. The second sensor 120 includes a shaft 121, a detector 122 that can rotate around the shaft 121, and an optical sensor 123 that includes a light emitting element and a light receiving element that receives light emitted from the light emitting element. ing.

  The detector 122 protrudes into the transport path 23. When an external force is not applied to one end of the detector 122, the other end of the detector 122 enters an optical path from the light emitting element to the light receiving element of the optical sensor 123, and blocks light passing through the optical path. At this time, a low level signal is output from the optical sensor 123 to the control unit 130. When one end of the detector 122 is pushed and rotated by the tip of the recording paper 19, the other end of the detector 122 is removed from the optical path, and light passes through the optical path. At this time, a high level signal is output from the optical sensor 123 to the control unit 130.

  When the signal from the optical sensor 123 changes from the low level to the high level, the control unit 130 determines that the downstream end in the conveyance direction 15 of the recording paper 19 has reached the second sensor 120. On the other hand, when the signal from the optical sensor 123 changes from the high level to the low level, the control unit 130 determines that the upstream end in the conveyance direction 15 of the recording paper 19 has reached the second sensor 120. That is, the control unit 130 detects the downstream end and the upstream end in the transport direction 15 of the recording paper 19 transported through the transport path 23 based on the signal from the optical sensor 123. As described above, the sheet edge detection unit according to the present invention includes the second sensor 120 and the control unit 130.

[Bypass tray 31]
As shown in FIG. 2, a manual feed tray 31 is provided on the back surface of the printer unit 2. The manual feed tray 31 can place recording papers 19 of various sizes. The recording paper 19 is placed on the manual feed tray 31 so that the leading end of the recording paper 19 comes into contact with the nipping portion of the recording paper 19 in the conveying roller pair 89 as indicated by a one-dot chain line in FIG. As a result, the recording paper 19 placed on the manual feed tray 31 can be supplied to the transport path 23.

  When the recording paper 19 is placed on the manual feed tray 31, the leading edge of the recording paper 19 presses one end of the detector 122 of the second sensor 120. That is, when the recording paper 19 is placed on the manual feed tray 31, a high level signal is output from the optical sensor 123 to the control unit 130 with the paper feed roller 25 not rotating. This state is a detection state of the detection result of the manual feed tray 31. Receiving the high level signal, the control unit 130 determines that the recording paper 19 is placed on the manual feed tray 31. That is, the control unit 130 detects the presence or absence of the recording paper 19 placed on the manual feed tray 31. As described above, the manual sheet presence / absence detection unit of the present invention includes the second sensor 120 and the control unit 130.

[Recording unit 24]
As shown in FIG. 2, the recording unit 24 is disposed at a position facing the platen 42 in the conveyance path 23. The platen 42 is a plate-like member, and supports the recording paper 19 that is transported along the transport direction in the transport path 23. The recording unit 24 includes an inkjet recording head 39 and a carriage 38 on which the recording head 39 is mounted. The carriage 38 is supported by the frame of the printer unit 2 so as to be reciprocable in the left-right direction 9.

  The recording head 39 is disposed on the lower surface of the carriage 38. Further, the recording head 39 includes a plurality of nozzles 40 that eject ink droplets. Each nozzle 40 corresponds to one of cyan, magenta, yellow, and black. Each color ink is supplied to the corresponding nozzle 40 from an ink cartridge (not shown).

  While the carriage 38 is reciprocated, ink droplets of each color are ejected from the plurality of nozzles 40 toward the platen 42. As a result, an image is recorded on the recording paper 19 supported by the platen 42. The ink droplet ejection described above is controlled by the control unit 130 described later.

[Rotary encoder 68]
As shown in FIG. 2, a rotary encoder 68 that detects the rotation amount of the transport roller 87 is provided. The rotary encoder 68 includes an encoder disk 51 and an optical sensor 60 which are provided coaxially with the transport roller 87 and rotate together with the transport roller 87. The encoder disk 51 is formed with a pattern in which transmissive portions through which light is transmitted and non-transmissive portions through which light is not transmitted are alternately arranged at equal pitches in the circumferential direction. When the encoder disk 51 rotates together with the transport roller 87, a pulse signal is generated each time the optical sensor 60 detects the transmission part and the non-transmission part of the rotary encoder 68. The pulse signal generated by the optical sensor 60 is output to the control unit 130 described later.

[Control unit 130]
Hereinafter, the schematic configuration of the control unit 130 will be described with reference to FIG. 3. The control unit 130 includes a CPU 131, a ROM 132, a RAM 133 (an example of a storage unit of the present invention), an EEPROM 134, an ASIC 135, and an internal bus 137 that interconnects these components.

  The ROM 132 stores a program for the CPU 131 to control various operations including image recording control described later. The EEPROM 134 stores settings, flags, and the like that should be retained even after the power is turned off. The RAM 133 is used as a storage area for temporarily recording data, signals, and the like used when the CPU 131 executes the program. The RAM 133 stores a first length 1L described later.

  The ASIC 135 incorporates a drive circuit for controlling each motor mounted on the multifunction machine 1 such as a paper feed motor 76 and a transport motor 59. When a driving signal for rotating each motor is input from the CPU 131 to a driving circuit corresponding to a predetermined motor, a driving current corresponding to the driving signal is output from the driving circuit to the corresponding motor. Thereby, the corresponding motor rotates forward or reverse at a predetermined rotational speed.

  The ASIC 135 is connected to the rotary encoder 68, the first sensor 110, and the optical sensors 60, 113, and 123 of the second sensor 120. The CPU 131 calculates the rotation amount of the transport roller 87 based on the pulse signal from the optical sensor 60. Further, the CPU 131 detects whether or not the paper feed tray 20 is located at the first position based on the signal from the optical sensor 113, and is transported through the transport path 23 based on the signal from the optical sensor 123. The downstream end and the upstream end of the recording paper 19 in the conveyance direction 15 are detected.

  The operation panel 4 is connected to the ASIC 135. The CPU 131 controls the various operations described above based on input signals from the operation panel 4.

[Image recording control]
As will be described below, the control unit 130 performs image recording control according to the flowcharts shown in FIGS. 4, 5, and 10 (A). Thereby, the present invention is realized.

  First, the process in the flowchart of FIG. In the present embodiment, the control unit 130 executes the process shown in FIG. 10A in parallel with the image recording control described below. Here, in FIG. 10A, whether or not the paper feed tray 20 has been removed from the multifunction device 1 after the previous image recording on the recording paper 19 (specifically, the paper feed tray 20 has been removed). Then, it is determined whether it has been attached again, that is, whether or not it has been attached / detached).

  This will be described in detail below. The control unit 130 determines whether the paper feed tray 20 is based on a signal input from the optical sensor 113 of the first sensor 110 at all times or every fixed time (for example, 10 μs) from when the multifunction device 1 is turned on. It is detected whether or not it is located at the first position (S610). Here, when the detection result of the paper feed tray 20 by the first sensor 110 changes from the detection state to the non-detection state, the control unit 130 determines that the paper feed tray 20 has been removed.

  If the control unit 130 determines that the paper feed tray 20 is not positioned at the first position, that is, if the control unit 130 determines that the paper feed tray 20 has been removed (S610: Yes), the first sensor 110 continues. Based on the signal input from the optical sensor 113, it is detected whether or not the paper feed tray 20 is positioned at the first position (S620). Here, when the detection result changes from the non-detection state to the detection state, the control unit 130 determines that the paper feed tray 20 is attached.

  If the control unit 130 determines that the paper feed tray 20 is located at the first position, that is, if the control unit 130 determines that the removed paper feed tray 20 is mounted on the multifunction machine 1 again (S620: Yes), the position change is performed. Information is stored in the RAM 133 (S630). Here, the position change information is information indicating that the paper feed tray 20 has been removed and attached (removed) after the previous image recording on the recording paper 19, for example, the paper feed tray 20 has been removed. In this case, “1” is a so-called flag stored in the RAM 133 as the position change information. The processing in steps S610 to S630 is an example of the position change storage control unit of the present invention. In the present embodiment, the position change information is reset after step S100 described later and before step S110. However, in the case of manual sheet feeding (step S20 described later: Yes), the position change information is not reset.

  Hereinafter, processing in the flowcharts of FIGS. 4 and 5 will be described. The control unit 130 receives, that is, acquires and stores the image data, the second length 2L, and the third length 3L, which are recorded on the recording paper 19 transmitted from the external information device to the multifunction machine 1 and stored in the RAM 133. (S10). Here, as shown in FIG. 6, the second length 2 </ b> L corresponds to the image 34 recorded on the recording sheet 19 by the recording unit 24 ejecting ink droplets onto the recording sheet 19 based on the image data. It is the length of the conveyance direction 15. The third length 3L is a part of information indicating the size of the recording paper 19 on which the image data is recorded. Specifically, the size is configured by the length of the short side and the length of the long side of the recording paper 19, and the third length 3L is the length of the short side, that is, the length in the transport direction 15. is there. The process of step S10 is an example of an acquisition unit of the present invention.

  Note that the control unit 130 may acquire the image data, the second length 2L, and the third length 3L from other than the external information device. For example, the multifunction device 1 is provided with a slot for a small memory card, and the control unit 130 is connected to the small memory card inserted into the slot, and stores the image data stored in the small memory card, the second length. 2L and the third length 3L may be acquired. Further, the third length 3L may be acquired based on designation by the user operating the operation panel 4.

  Next, the control unit 130 determines whether or not the recording paper 19 is placed on the manual feed tray 31 based on the input signal from the optical sensor 123 (S20). When the recording paper 19 is placed on the manual feed tray 31, that is, when the detection result of the manual feed tray 31 by the second sensor 120 is in the detection state (S20: Yes), the control unit 130 is acquired in step S10. The third length 3L is set to the length of the recording direction 19 of the recording paper 19 placed on the manual feed tray 31 (S30).

  On the other hand, when the recording paper 19 is not placed on the manual feed tray 31 (S20: No), the control unit 130 determines whether or not position change information is stored in the RAM 133 (S40).

  When the position change information is not stored in the RAM 133 (S40: No), the control unit 130 uses the first length 1L stored in the RAM 133 as the conveyance direction 15 of the recording paper 19 placed on the paper feed tray 20. (S50). Here, the first length 1L is calculated in step S100 based on the input signal from the optical sensor 123 and stored in the RAM 133, as will be described later. In step S50, the first length 1L stored in the RAM 133 in step S100 in the process of image recording on the past (most recent in the present embodiment) recording paper 19 is recorded on the paper feed tray 20. The length of the sheet 19 in the conveyance direction 15 is set.

  On the other hand, when the position change information is stored in the RAM 133 (S40: Yes), the control unit 130 uses the third length 3L acquired in step S10 for the recording paper 19 placed on the paper feed tray 20. The length is set to the conveyance direction 15 (S60).

  When the recording paper 19 is placed on the manual feed tray 31 (S20: Yes), the first length 1L is not stored in the RAM 133 because step S100 described later is not executed. That is, in steps S90 and S100 described later, when the detection result of the manual feed tray 31 by the second sensor 120 is in the detection state, the control unit 130 does not store the first length 1L in the RAM 133. From the above, the processing of steps S20, S80, S90, and S100 is an example of the first length storage control unit of the present invention.

  As described above, when the length of the recording sheet 19 in the conveyance direction 15 is set, the control unit 130 rotates the paper feed roller 25 and the conveyance roller 87. As a result, the recording paper 19 placed on the paper feed tray 20 or the recording paper 19 placed on the manual feed tray 31 is transported in the transport direction 15 (S70). Next, the control unit 130 determines whether or not the recording paper 19 is placed on the manual feed tray 31 based on the input signal from the optical sensor 123 (S80). When the recording paper 19 is not placed on the manual feed tray 31 (S80: No), the control unit 130 executes steps S90 and S100 described below, and then executes step S110. When 19 is mounted (S80: Yes), the control unit 130 executes Step S110 without executing Steps S90 and S100.

  When the position change information is stored in the RAM 133 (S90: Yes), the control unit 130 calculates the first length 1L and stores it in the RAM 133 (S100). Here, the controller 130 is based on the rotation amount of the transport roller 87 from when the second sensor 120 detects the leading edge of the recording paper 19 until the trailing edge is detected, that is, based on the detection result by the second sensor 120. Based on this, the first length 1L is calculated. The rotation amount is calculated based on a pulse signal generated by the optical sensor 60 and output to the control unit 130. The process of step S100 is an example of a calculation unit of the present invention.

  Note that step S80, step S100, and image recording (such as step S240) on the recording paper 19 described later are not necessarily performed according to the order of the flowcharts, and these steps may be performed in parallel. For example, when the rear end of the conveyance direction 15 of the recording paper 19 is detected by the second sensor 120 (S100), an image is recorded by the recording unit 24 near the front end of the conveyance direction 15 of the recording paper 19. (S240).

  When the current image recording on the recording paper 19 is printing with margins, that is, when printing is not borderless (S110: No), image recording is executed according to steps S200 to S250 of the flowchart of FIG. On the other hand, if the current image recording on the recording paper 19 is printing without margins, that is, borderless printing (S110: Yes), image recording is executed according to the flowchart of FIG. Information about whether or not the image recording is borderless printing is included in the information transmitted from the external information device in step S10, for example. Alternatively, whether the image recording is borderless printing is designated by the operation of the operation panel 4 by the user.

  Hereinafter, the bordered printing process will be described based on the flowchart of FIG. First, the control unit 130 determines whether the second length 2L acquired in step S10 is equal to or longer than the length set in steps S30, S50, and S60 (hereinafter, the length is also referred to as a set length SL). It is determined whether or not (S200). When the second length 2L is equal to or longer than the set length SL (S200: Yes), the control unit 130 stops the image recording process on the assumption that the size of the recording paper 19 on which the image is recorded is abnormal (S210). Specifically, the abnormality is displayed on the liquid crystal display unit 11 and the recording paper 19 is forcibly discharged to the paper discharge tray 21.

  On the other hand, when the second length 2L is shorter than the set length SL (S200: No), the control unit 130 determines whether centering is instructed (S220). Here, the centering is to record an image on the recording sheet 19 so that the center of the recording sheet 19 in the conveyance direction 15 coincides with the center of the conveyance direction 15 of the image recorded on the recording sheet 19. It is. In addition, the instructions of centering and front end alignment and rear end alignment described later are included in the information transmitted from the external information device in step S10, for example. Alternatively, the centering instruction is performed by the operation of the operation panel 4 by the user.

  When centering is instructed (S220: Yes), the control unit 130 calculates the margin M by (set length SL−second length 2L) / 2 (S230). Then, the control unit 130 records the image 34 on the recording sheet 19 with the margin M from the downstream end of the recording sheet 19 in the conveying direction 15 with the upstream side in the conveying direction 15 as the head (S240).

  This will be described in detail below. The control unit 130 conveys the recording paper 19 to the image recording start position. Here, the image recording start position is a position where the upstream side in the conveyance direction 15 by the margin M from the downstream end in the conveyance direction 15 of the recording paper 19 faces the nozzle 40 of the recording head 39 of the recording unit 24. Next, the control unit 130 ejects ink droplets onto the recording paper 19 at the image recording start position. Thereafter, conveyance of the recording paper 19 for a predetermined line feed and ink droplet ejection are alternately repeated. As a result, the image 34 is recorded on the recording paper 19 as shown in FIG.

  On the other hand, when the centering is not instructed (S220: No), in the present embodiment, the control unit 130 determines that the leading end is instructed. Here, the leading end refers to a position upstream by a margin M (see FIG. 6B) set in advance from the downstream end in the conveyance direction 15 of the recording paper 19 and the image recorded on the recording paper 19. An image is recorded on the recording paper 19 so that the head is equal to or less than a preset position threshold value. When the above determination is made, the control unit 130 records the image 34 on the recording paper 19 with the margin M as the upstream position from the downstream end in the conveyance direction 15 of the recording paper 19 (S250). This will be described in detail below. The control unit 130 conveys the recording paper 19 to the image recording start position. Next, the control unit 130 ejects ink droplets onto the recording paper 19 at the image recording start position. Thereafter, conveyance of the recording paper 19 for a predetermined line feed and ink droplet ejection are alternately repeated. As a result, an image 34 is recorded on the recording paper 19 as shown in FIG.

  Next, the borderless printing process will be described based on the flowchart of FIG. In the description based on FIG. 5, the detailed description of portions overlapping with the description based on steps S <b> 200 to S <b> 250 in FIG. 4 is omitted. First, the control unit 130 executes processing similar to that in step S200 (S400).

  When the second length 2L is equal to or shorter than the set length SL (S400: No), the control unit 130 determines whether centering, front end alignment, or rear end alignment is instructed (S410, S430). Here, the rear end alignment means that the image on the recording sheet 19 is such that the downstream end in the conveyance direction 15 of the recording sheet 19 and the end of the image recorded on the recording sheet 19 are equal to or less than the position threshold value. Is to record.

  When centering is instructed (S410: Yes), the control unit 130 starts from the downstream end of the recording sheet 19 in the conveyance direction 15 and the margin M calculated by (set length SL−second length 2L) / 2. Thus, the image 34 is recorded on the recording paper 19 with the upstream side as the head (S420). This will be described in detail below. The control unit 130 conveys the recording paper 19 to the image recording start position. Next, the control unit 130 ejects ink droplets onto the recording paper 19 at the image recording start position. Thereafter, conveyance of the recording paper 19 for a predetermined line feed and ink droplet ejection are alternately repeated. Thereby, as shown in FIG. 6C, the image 34 is recorded on the recording paper 19 by centering. Here, steps S400 to S420 are borderless printing processing. However, in FIG. 6C, the second length 2L is shorter than the set length SL, and thus no borderless printing is performed. Note that the result of image recording in step S420 is borderless when the second length 2L is equal to the set length SL.

  When the leading edge is instructed (S410: No, S430: No), the control unit 130 records the image 34 on the recording paper 19 with the downstream end in the transport direction 15 of the recording paper 19 as the head (S450). This will be described in detail below. The control unit 130 conveys the recording paper 19 to the image recording start position. Here, in the leading edge alignment in the case of borderless printing, there is no margin M at the downstream end in the transport direction. Therefore, in step S450, the image recording start position is a position where the downstream end in the conveyance direction 15 of the recording paper 19 faces the nozzle 40 of the recording head 39 of the recording unit 24. Next, the control unit 130 ejects ink droplets onto the recording paper 19 at the image recording start position. Thereafter, conveyance of the recording paper 19 for a predetermined line feed and ink droplet ejection are alternately repeated. As a result, an image 34 is recorded on the recording paper 19 as shown in FIG. In FIG. 6D, a margin M of (set length SL−second length 2L) is formed on the upstream side in the conveyance direction 15 of the recording sheet 19 on which the image is recorded.

  When rear end alignment is instructed (S410: No, S430: Yes), the control unit 130 is calculated from the downstream end in the conveyance direction 15 of the recording paper 19 (set length SL−second length 2L). The image 34 is recorded on the recording paper 19 starting from the position upstream by the margin M (S440). This will be described in detail below. The control unit 130 conveys the recording paper 19 to the image recording start position when the margin M is present. Next, the control unit 130 ejects ink droplets onto the recording paper 19 at the image recording start position. Thereafter, conveyance of the recording paper 19 for a predetermined line feed and ink droplet ejection are alternately repeated. As a result, an image 34 is recorded on the recording paper 19 as shown in FIG. In FIG. 7A, the upstream end in the transport direction 15 of the image 34 recorded on the recording paper 19 coincides with the upstream end in the transport direction 15 of the recording paper 19.

  On the other hand, also when the second length 2L is longer than the set length SL (S400: Yes), the control unit 130 determines whether centering, leading edge alignment, or trailing edge alignment is instructed (S460, S490). ).

  When centering is instructed (S460: Yes), the control unit 130 controls the recording unit 24 so that predetermined image data is not recorded on the recording paper 19. In other words, the control unit 130 records image data other than the predetermined image data on the recording paper 19 (S470, S480). Here, the predetermined image data corresponds to an image 34A (see FIG. 7B) recorded upstream from the top by the transport direction 15 (second length 2L−set length SL) / 2. The image data corresponds to the image data and the image 34B (see FIG. 7B) recorded on the downstream side in the transport direction 15 (second length 2L−set length SL) / 2 from the end. Here, the length of the images 34 </ b> A and 34 </ b> B in the conveyance direction 15 is an example of the protrusion amount of the present invention. As described above, when recording an image on the recording paper 19, the control unit 130 skips the image data corresponding to the image 34A, and based on the image data (image data corresponding to the image 34) following the skipped image data. Ink droplets are ejected onto the recording paper 19. The control unit 130 also skips image data corresponding to the image 34B following the image data corresponding to the image 34. As a result, an image 34 is recorded on the recording paper 19 as shown in FIG.

  If rear end alignment is instructed (S460: No, S490: Yes), the control unit 130 controls the recording unit 24 so that predetermined image data is not recorded on the recording paper 19. In other words, the control unit 130 records image data other than the predetermined image data on the recording paper 19 (S500). Here, the predetermined image data corresponds to the image 34C (see FIG. 7C) recorded on the upstream side in the transport direction 15 (second length 2L−set length SL) from the top. It is. Here, the length of the image 34C in the conveyance direction 15 is an example of the amount of protrusion of the present invention. As described above, when recording an image on the recording paper 19, the control unit 130 skips the image data corresponding to the image 34C, and based on the image data (image data corresponding to the image 34) following the skipped image data. Ink droplets are ejected onto the recording paper 19. As a result, an image 34 is recorded on the recording paper 19 as shown in FIG.

  When the leading edge is instructed (S460: No, S490: No), the control unit 130 controls the recording unit 24 so that predetermined image data is not recorded on the recording paper 19. In other words, the control unit 130 records image data other than the predetermined image data on the recording sheet 19 (S510, S520). Here, the predetermined image data is image data corresponding to an image 34D (see FIG. 7D) recorded downstream from the end by the transport direction 15 (second length 2L−set length SL). It is. Here, the length of the image 34D in the conveyance direction 15 is an example of the amount of protrusion of the present invention. As described above, when the image is recorded on the recording paper 19, the control unit 130 ejects ink droplets onto the recording paper 19 based on the image data from the beginning to immediately before the image data corresponding to the image 34 </ b> D. . In addition, the control unit 130 skips image data corresponding to the image 34D. As a result, an image 34 is recorded on the recording paper 19 as shown in FIG.

  7B, 7C, 7D, the upstream end and the downstream end in the transport direction 15 of the image 34 recorded on the recording paper 19 in steps S470, S480, S500, S510, and S520 are The recording sheet 19 coincides with the upstream end and the downstream end of the conveyance direction 15 respectively.

  As described above, the processes of steps S230, S240, S420, S470, and S480, which are processes performed by the control unit 130 when centering is instructed, are an example of the centering control unit of the present invention. Specifically, when the first length 1L is set to the set length SL (S50), the control unit 130, in each of the above steps, the image data acquired in step S10, the second length 2L, and the RAM 133. Based on the first length 1L stored in the recording medium 19, an image in which the center of the transport direction 15 of the second length 2L coincides with the center of the transport direction 15 of the first length 1L is formed on the recording paper 19. In addition, the recording unit 24, the paper feed roller 25, the transport roller pair 89, and the paper discharge roller pair 92 are controlled. When the detection result of the manual feed tray 31 is in the detection state (S20: Yes), the control unit 130 sets the image data acquired in step S10, the second length 2L, and step S30 in each of the above steps. Based on the third length 3L set as the length SL, an image is formed on the recording paper 19 in which the center of the transport direction 15 of the second length 2L coincides with the center of the transport direction 15 of the third length 3L. Thus, the recording unit 24, the paper feed roller 25, the transport roller pair 89, and the paper discharge roller pair 92 are controlled.

  Further, the processes of steps S440 and S500, which are processes performed by the control unit 130 when the rear end alignment is instructed, are an example of the upper end alignment control unit of the present invention. Specifically, in each of the above steps, the recording paper 19 is recorded on the basis of the image data acquired in step S10, the second length 2L, and the detection result (output signal from the optical sensor 123) by the second sensor 120. Ink droplets are ejected to the recording unit 24 so that the difference between the upstream end position in the transport direction 15 of the recorded image 34 and the upstream end position in the transport direction 15 of the recording paper 19 is equal to or less than the position threshold value.

[Number of nozzles 40 used in borderless printing]
In the present embodiment, image recording onto the recording paper 19 is performed by alternately discharging ink droplets from the nozzle 40 onto the recording paper 19 and conveying the recording paper 19 for a predetermined line feed. In borderless printing, when images are recorded on the edge portion of the recording paper 19, that is, on the downstream end portion and the upstream end portion in the conveyance direction 15 of the recording paper 19, a plurality of prints are provided on the recording head 39 of the recording unit 24. The number of nozzles 40 used is limited.

  Specifically, when an image is recorded on the downstream end portion of the recording paper 19 in the conveyance direction 15, the number of nozzles 40 used is increased step by step every time the recording paper 19 is conveyed by a predetermined line feed. . On the other hand, when an image is recorded on the upstream end portion of the recording paper 19 in the conveyance direction 15, the number of nozzles 40 used is decreased step by step every time the recording paper 19 is conveyed by a predetermined line feed. The nozzle 40 to be used is transmitted from the external information device to the multi-function device 1 in a state linked to the image data acquired in step S10, and is acquired by the control unit 130 together with the image data. For example, the image data corresponding to the image in the first row and information indicating which nozzle 40 of the plurality of nozzles 40 is used when the image is recorded are linked to each other.

  As described above, the number of nozzles used is increased or decreased stepwise, so that the accuracy of matching between the edge of the recording paper 19 and the edge of the image 34 can be improved. In the present embodiment, the downstream end (front end) portion in the transport direction 15 in FIG. 6D, the upstream end (rear end) portion in the transport direction 15 in FIG. 7A, and the transport direction 15 in FIG. 7C. The accuracy of matching the edge of the recording paper 19 and the edge of the image 34 can be improved at the upstream end (rear end) and the downstream end (front end) in the transport direction 15 in FIG.

  On the other hand, the number of used nozzles may not be increased or decreased in stages. In this embodiment, the upstream end (rear end) and the downstream end (front end) of the transport direction 15 in FIG. 7B, the downstream end (front end) of the transport direction 15 in FIG. 7C, and FIG. The upstream end (rear end) portion in the transport direction 15 in (D) corresponds to this case. In this case, the image recorded on the edge of the recording paper 19 is an image recorded at a position that is not originally an edge. Therefore, the number of nozzles linked to the image data corresponding to the image recorded on the edge is not limited because the image is recorded on the edge. For this reason, when ink droplets are ejected from the nozzles 40 of the number of linked nozzles, ink droplets are ejected to the outside of the recording paper 19, and as a result, the platen 42 becomes dirty. Therefore, in the above case, when the image is recorded on the edge of the recording paper 19, the control unit 130 increases the number of nozzles used from zero at a stroke or from a plurality to zero at the edge. In this case, the matching accuracy between the edge of the recording paper 19 and the edge of the image 34 is not as good as when the number of used nozzles is increased or decreased stepwise.

  In the case of borderless printing, there are two types of patterns as described above for increasing or decreasing the number of nozzles used in the recording head 39. Accordingly, in borderless printing, ink droplets are allowed to be ejected to the outside of the recording paper 19 at the downstream end of the conveyance direction 15 of the recording paper 19 and allowed upstream of the conveyance direction 15 of the recording paper 19. If not, the upstream edge may be recorded with high accuracy. Specifically, the control unit 130 may perform image recording not with the leading edge as shown in FIG. 7D but with the trailing edge as shown in FIG.

[Effect of the embodiment]
In the present embodiment, centering of the recording paper 19 is performed assuming that the length of the recording paper 19 on which an image is to be recorded in the transport direction 15 is the first length 1L of the recording paper 19 on which an image has been recorded in the past. The Accordingly, when the recording sheet 19 on which an image is to be recorded is centered, it is not necessary to detect the recording sheet 19 by the second sensor 120. That is, in the present embodiment, it is possible to prevent the leading end of the recording paper 19 in the conveyance direction 15 from passing through the recording unit 24 before the length of the recording paper 19 in the conveyance direction 15 is calculated. Therefore, in the present embodiment, when the centering is executed based on the conveyance direction 15 of the recording paper 19, the recording paper 19 can be appropriately centered.

  Further, in the printer unit 2 of this embodiment, when an image for one page is recorded on one recording sheet 19, the side along the conveyance direction 15 of the recording sheet 19, that is, the short side of the recording sheet 19 is used as a reference. The centering is executed as follows. Therefore, this embodiment is a suitable structure for producing the effects described above.

  Further, when the paper feed tray 20 is moved from the first position to the second position after image recording on the latest recording paper 19, a recording paper 19 having a size different from that of the recording paper 19 is placed on the paper feed tray 20. It may have been done. That is, there is a possibility that the recording sheet 19 on which an image is to be recorded and the recording sheet 19 on which an image has been recorded most recently have different sizes. In such a case, the control unit 130 cannot appropriately perform centering. Therefore, in the present embodiment, in the above case, the first length 1L is calculated in step S100. As a result, in this configuration, even when the recording paper 19 placed on the paper feed tray 20 is replaced, the same effect as described above can be obtained again.

  Further, in the present embodiment, as described with reference to FIGS. 6 and 7, it is possible to prevent ink droplets from being ejected to an area where the recording paper 19 does not exist, that is, ink droplets from being ejected to the platen 42. it can. As a result, it is possible to prevent the recording paper 19 conveyed next on the platen 42 from being soiled by ink droplets attached to the platen 42. In addition, it is possible to prevent ejection of excess ink droplets.

  Normally, in the multi-function device 1 as in the present embodiment, when it is designated that paper is fed from the manual feed tray 31, the recording paper 19 is placed on the manual feed tray 31. That is, when the recording paper 19 is fed from the manual feed tray 31, it is unlikely that the recording paper 19 on which an image is to be recorded and the recording paper 19 on which an image has been recorded most recently have the same size. Therefore, it is less necessary to store the first length 1L in the RAM 133. In the multi-function device 1 of the present embodiment, step S100 is not executed in the case of manual paper feed (S20: Yes). Therefore, the storage in the RAM 133 of the first length 1L, which is less necessary as described above, is not executed. Can do.

[Modification 1]
The printer unit 2 may further include an optical sensor (not shown) that detects the presence or absence of the recording paper 19 placed on the paper feed tray 20. For example, the optical sensor includes a light receiving element disposed on the bottom plate of the paper feed tray 20 and a light emitting element disposed above the light receiving element and facing the light receiving element. When the recording paper 19 is placed on the paper feed tray 20, the optical path from the light emitting element to the light receiving element is blocked by the recording paper 19. On the other hand, when the recording paper 19 is not placed on the paper feed tray 20, light passes through the optical path. The optical sensor outputs a signal according to whether light is blocked or not to the control unit 130. The control unit 130 detects whether or not the recording paper 19 is placed on the paper feed tray 20 based on a signal from the optical sensor. As described above, the sheet presence / absence detection unit according to the present invention includes the optical sensor and the control unit 130.

  In the case of the first modification, the image recording control is executed in a process different from that in FIGS. 4 and 10A. Specifically, as shown in FIG. 8, steps S610 to S630 indicated by wavy lines are processes different from those in FIG. 4. Further, processing according to the flowchart of FIG. 10B is executed instead of FIG.

  First, the process in the flowchart of FIG. 10B will be described. In the present embodiment, the control unit 130 executes the process shown in FIG. 10B in parallel with the image recording control described below (process according to the flowchart of FIG. 8). Here, in FIG. 10B, the recording sheet 19 placed on the paper feed tray 20 in the previous image recording on the recording paper 19 becomes zero, and then the recording paper 19 is loaded again on the paper feed tray 20. It is determined whether it has been placed.

  This will be described in detail below. The control unit 130 loads the recording paper 19 on the paper feed tray 20 based on a signal input from the optical sensor at all times or every fixed time (for example, 10 μs) from when the multifunction device 1 is turned on. It is detected whether it is placed (S810).

  When the recording paper 19 is placed on the paper feed tray 20 from the state where it is not placed, the control unit 130 determines that the recording paper 19 placed on the paper feed tray 20 has become zero. (S810: Yes). The controller 130 continues to detect whether the recording paper 19 is placed on the paper feed tray 20 based on the signal input from the optical sensor (S820).

  When the recording paper 19 is not placed on the paper feed tray 20, the control unit 130 determines that the recording paper 19 is placed again on the paper feed tray 20 (S <b> 820). : Yes).

  When the control unit 130 determines that the recording sheet 19 is placed again on the paper feed tray 20 (S820: Yes), the sheet state change information is stored in the RAM 133 (S830). Here, in the sheet state change information, the recording paper 19 placed on the paper feed tray 20 after the previous image recording on the recording paper 19 becomes zero, and then the recording paper 19 is placed again on the paper feed tray 20. For example, when the recording paper 19 is placed again on the paper feed tray 20, “1” is a so-called flag stored in the RAM 133 as the sheet state change information. The processing in steps S810 to S830 is an example of the state change storage control unit of the present invention. In the first modification, the sheet state change information is reset after step S630 and before step S110, which will be described later. However, in the case of manual sheet feeding (step S20: Yes), the sheet state change information is not reset.

  Hereinafter, processing different from that in FIG. 4 will be described with respect to the processing in the flowchart of FIG. In step S610, the control unit 130 determines whether or not the above-described step S830 is executed and the sheet state change information is stored in the RAM 133. When the sheet state change information is stored in the RAM 133 (S610: Yes), the control unit 130 executes Step S60. When the sheet state change information is not stored in the RAM 133 (S610: No), the control unit 130 performs Step S50. Execute.

  In the first modification, steps S620 and S630 are executed instead of steps S90 and S100 in the above-described embodiment. That is, in the first modification, when the sheet state change information is stored in the RAM 133 (S620: Yes), the control unit 130 calculates the first length 1L and stores it in the RAM 133 (S630). The process of step S630 is an example of the calculation unit of the present invention.

  In the first modification, the control unit 130 detects whether or not the recording paper 19 is placed on the paper feed tray 20 based on a signal from the optical sensor. However, the detection is performed by other methods. It may be done. For example, if the second sensor 120 does not detect the recording sheet 19 even after a preset time has elapsed after the sheet feeding roller 25 has been rotated, the control unit 130 stores the recording sheet 19 in the sheet feeding tray 20. It may be determined that is not placed. In this case, the sheet presence / absence detection unit of the present invention includes the optical sensor 123 of the second sensor 120 and the control unit 130.

  In the first modification, after the image is recorded on the latest recording paper 19, the detection result by the optical sensor, which is an example of the sheet presence / absence detection unit of the present invention, changes from the absence of the recording paper 19 to the existing state, that is, the latest recording paper. When the recording paper 19 is newly placed on the paper feed tray 20 after the image is recorded on the paper 19, there is a possibility that the recording paper 19 having a size different from that of the recording paper 19 is placed on the paper feed tray 20. That is, there is a possibility that the recording sheet 19 on which an image is to be recorded and the recording sheet 19 on which an image has been recorded most recently have different sizes. In such a case, the control unit 130 cannot appropriately perform centering. Therefore, in the first modification, in the above case, the first length 1L is calculated in step S630. As a result, in the present embodiment, even when the recording paper 19 placed on the paper feed tray 20 is replaced, the same effect as described above can be obtained again.

[Modification 2]
As shown in FIG. 9, between step S20 and step S40, the control unit 130 presets the difference between the third length 3L acquired in step S10 and the first length 1L stored in the RAM 133. It may be determined whether or not the length is equal to or greater than the set length threshold (S700). If the difference is smaller than the length threshold value (S700: No), the control unit 130 sets the third length 3L to the length of the recording sheet 19 placed on the paper feed tray 20 in the conveyance direction 15. It may be set (S30). That is, in steps S230, S240, S420, S470, and S480, the control unit 130 does not based on the image data and the second length 2L and the first length 1L, but on the image data and the second length 2L and the first length. Based on the three lengths 3L, image recording on the recording paper 19 is performed by centering. That is, when the difference is smaller than the length threshold (S700: No), the process of the centering control unit of the present invention is not executed. In other words, the processing of the centering control means of the present invention can be executed on condition that the difference is equal to or greater than the length threshold.

  In the second modification, the third length 3L is the length in the conveyance direction 15 of the recording paper 19, and is specified by the user and stored in the RAM 133. For example, the third length 3L may be set by a user's operation on the operation panel 4, or may be transmitted from an external information device to the multifunction device 1 together with image data. According to the second modification, contrary to the third length 3L stored in the RAM 133, the length in the transport direction 15 of the recording paper 19 actually transported through the transport path 23 is the first length 1L. Even in some cases, the centering of the recording paper 19 can be appropriately executed by executing the processing of the centering control means of the present invention.

[Modification 3]
In the above-described embodiment, information on whether an image is recorded on the recording paper 19 by centering, leading edge alignment, or trailing edge alignment is included in the information transmitted from the external information device. Alternatively, the information is sent to the control unit 130 by the operation of the operation panel 4 by the user. However, whether the image is recorded on the recording paper 19 by centering, leading edge alignment, or trailing edge alignment may be determined by other factors.

  For example, when the second length 2L acquired in step S10 is longer than the first length 1L stored in the RAM 133, an image is recorded on the recording paper 19 by rear end alignment, that is, the upper end alignment control of the present invention. When the means is executed and the second length 2L is equal to or less than the first length 1L, an image is recorded on the recording paper 19 by centering, that is, the centering control means of the present invention may be executed.

  In the example described in the third modification, when there is a possibility that ink droplets may be ejected in an area where the recording paper 19 does not exist, the ink at the upstream end in the conveyance direction 15 of the recording paper 19 is executed by performing rear end alignment. The accuracy of preventing the droplets from adhering to the platen 42 can be increased. On the other hand, when there is no possibility that ink droplets are ejected to an area where the recording paper 19 does not exist, the centering of the recording paper 19 can be appropriately executed by performing the centering.

[Modification 4]
In the multifunction device 1 according to the above-described embodiment, the recording paper 19 accommodated in the paper feed tray 20 is rectangular, and the recording paper 19 is accommodated in the paper feeding tray 20 in a horizontally placed state when viewed from the front of the multifunction device 1. It was. However, the multifunction device 1 may be configured to store the recording paper 19 in the paper feed tray 20 in a vertically placed state when viewed from the front of the multifunction device 1.

  Even when the multi-function device 1 is configured as described above, for example, when two pages of images are recorded on one recording sheet 91, the present invention can be applied. That is, when two pages of images are recorded on one sheet of recording paper 91, the present invention is applicable because centering, leading edge alignment, and trailing edge alignment are executed based on the conveyance direction 15.

DESCRIPTION OF SYMBOLS 1 ... Multifunctional device 2 ... Printer part 15 ... Conveyance direction 19 ... Recording paper 20 ... Paper feed tray 24 ... Recording part 42 ... Platen 120 ... Second sensor 130 ... Control unit 133 ... RAM

Claims (11)

A tray on which the sheet is placed and moved between a first position where the sheet can be conveyed to the conveyance path and a second position where the sheet cannot be conveyed ;
The placed sheets the tray and conveying portion for conveying along the conveying path,
A platen for supporting a sheet conveyed through the conveyance path;
A recording unit that is provided facing the platen, and that records an image on a sheet supported by the platen by discharging ink droplets toward the platen;
A sheet end detection unit that detects a downstream end and an upstream end in a conveyance direction of the sheet conveyed on the conveyance path;
Calculating means for calculating a first length in the conveying direction of the sheet conveyed along the conveying path based on a detection result by the sheet edge detecting unit;
A storage unit for storing the first length calculated by the calculating means;
Acquisition means for acquiring image data recorded on the sheet, and a second length in the conveying direction of the image recorded on the sheet based on the image data;
Based on the image data and the second length acquired by the acquisition means and the first length of the sheet stored in the storage unit, the center of the second length coincides with the center of the first length. Centering control means for controlling the recording unit and the conveying unit so as to form an image on a sheet;
A tray detector for detecting whether or not the tray is located at the first position;
Position change information indicating a change in the position of the tray on condition that the detection result of the tray by the tray detection unit has changed from the detection state to the non-detection state after image recording on the sheet conveyed most recently from the tray. Position change storage control means for storing the above in the storage unit ,
When the position change information is stored in the storage unit, the calculating unit is configured to determine a first length in the transport direction of the sheet transported on the transport path based on a detection result by the sheet end detection unit. calculate the ink jet recording apparatus. A tray for placing sheets;
A transport unit that transports the sheet placed on the tray along the transport path;
A platen for supporting a sheet conveyed through the conveyance path;
A recording unit that is provided facing the platen, and that records an image on a sheet supported by the platen by discharging ink droplets toward the platen;
A sheet end detection unit that detects a downstream end and an upstream end in a conveyance direction of the sheet conveyed on the conveyance path;
Calculating means for calculating a first length in the conveying direction of the sheet conveyed along the conveying path based on a detection result by the sheet edge detecting unit;
A storage unit for storing the first length calculated by the calculating means;
Acquisition means for acquiring image data recorded on the sheet, and a second length in the conveying direction of the image recorded on the sheet based on the image data;
Based on the image data and the second length acquired by the acquisition means and the first length of the sheet stored in the storage unit, the center of the second length coincides with the center of the first length. Centering control means for controlling the recording unit and the conveying unit so as to form an image on a sheet;
A sheet presence / absence detection unit for detecting the presence / absence of a sheet placed on the tray;
After the image is recorded on the sheet conveyed most recently from the tray, a change in the presence / absence of a sheet in the tray is performed on the condition that the detection result of the tray by the sheet presence / absence detection unit has changed from a sheet non-existing state to a sheet present state. State change storage control means for storing sheet state change information indicating the above in the storage unit ,
When the sheet state change information is stored in the storage unit, the calculation unit is configured to determine a first length in the conveyance direction of the sheet conveyed on the conveyance path based on a detection result by the sheet end detection unit. an ink jet recording apparatus you calculated is. The tray is an ink jet recording apparatus according to claim 1 or 2 long sides of a rectangular sheet is to convey capable mounted as a downstream end and the upstream end of the conveying direction. The storage unit stores a third length in the conveyance direction of the sheet designated by the user,
Said central register control means, any of claims 1 to 3, which is executed on condition that the difference between the first length and the third length stored in the storage unit is preset length threshold or 2. An ink jet recording apparatus according to 1. The centering control means is provided on the upstream side of the upstream end of the sheet in the transport direction on condition that the second length acquired by the acquisition means is longer than the first length stored in the storage unit. an ink jet recording apparatus according to claim 1 for controlling the recording unit so as not to eject ink droplets based on the image data corresponding to an image to be recorded 4. The centering control means is provided on the downstream side of the downstream end in the conveyance direction of the sheet on the condition that the second length acquired by the acquisition means is longer than the first length stored in the storage unit. The inkjet recording apparatus according to claim 5 , wherein the recording unit is controlled so as not to eject ink droplets based on image data corresponding to an image to be recorded. Based on the image data and the second length acquired by the acquisition means and the detection result by the sheet edge detection unit, the position of the upstream end of the image recorded on the sheet in the conveyance direction and the conveyance direction of the sheet An upper end alignment control unit that causes the recording unit to eject ink droplets so that the difference from the position of the upstream end is equal to or less than a preset position threshold;
The upper end alignment control means is executed on condition that the second length acquired by the acquisition means is longer than the first length stored in the storage unit,
Said central register control means, according to claim 5 or 6 which is executed on condition that the second length obtained by said obtaining means is equal to or less than the first length stored in the storage unit Inkjet recording apparatus. The upper alignment control means, according to claim 7 for controlling the recording unit so as not to eject ink droplets on the basis of image data than the downstream end of the conveying direction of the sheet corresponding to an image to be recorded on the downstream side Inkjet recording apparatus. A manual feed tray for placing sheets;
A manual sheet presence / absence detecting unit for detecting the presence / absence of a sheet placed on the manual feed tray;
A first length storage control unit that does not store the first length calculated by the calculation unit in the storage unit on condition that the detection result of the manual tray by the manual sheet presence detection unit is in a detection state; Further comprising
The transport unit is for transporting a sheet placed on the manual feed tray along a transport path,
The storage unit stores a third length in the conveyance direction of the sheet designated by the user,
The centering control unit is stored in the storage unit and the image data and the second length acquired by the acquisition unit on condition that the detection result of the manual tray by the manual sheet presence / absence detection unit is in a detection state. The recording unit and the conveying unit are controlled based on the third length so that an image in which the center of the second length coincides with the center of the third length is formed on the sheet. Item 9. The ink jet recording apparatus according to any one of Items 1 to 8 . The centering control unit is configured such that the center of the second length is the first length on the condition that the second length acquired by the acquiring unit is shorter than the first length stored in the storage unit. The amount of margin on the downstream side in the conveyance direction of the sheet is calculated so as to coincide with the center of the sheet, and the upstream side in the conveyance direction is the leading edge of the image by the margin amount from the downstream end in the conveyance direction of the sheet. the ink jet recording apparatus according to any one of claims 1 to record an image on the recording unit 9. The centering control unit is configured such that the center of the second length is the first length on condition that the second length acquired by the acquiring unit is longer than the first length stored in the storage unit. When the image is recorded on the sheet so as to coincide with the center of the sheet, the amount of protrusion of the image from the downstream end in the conveying direction of the sheet is calculated, and ink droplets are ejected based on the image data corresponding to the amount of protrusion. the ink-jet recording apparatus according to any one of claims 1 to 10 for controlling the recording unit so as not to.

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