JP2005335139A - Printer and printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a decrease of a printing speed by shortening a move distance of a carriage at the time of flushing. <P>SOLUTION: A printer is equipped with the carriage for moving nozzles which discharge a liquid. The printer carries out printing to a medium by moving the carriage back and forth, discharging the liquid from the nozzles which reciprocate together with the carriage, and making the liquid struck onto the medium. The printer carries out the flushing action of forcibly discharging the liquid from the nozzles to prevent the liquid from being struck on the medium. The flushing action is carried out within the range of the back-forth movement of the carriage at the time when printing is carried out to the medium. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a printing apparatus and a printing method.

  2. Related Art Inkjet printers that print on a medium by ejecting a liquid (such as ink) from a nozzle to form dots on the medium (such as paper, cloth, or OHP sheet) are known. Such an ink jet printer is provided with a carriage that reciprocates during printing. Then, the ink jet printer ejects ink from the nozzles of the head that moves with the carriage, and causes the ejected ink droplets to land on the medium to perform a printing process.

In such an ink jet printer, a flushing operation is performed in order to suppress thickening of ink. The flushing operation is an operation for forcibly ejecting ink so as not to land on the medium and ejecting the ink to the ink receiving portion. By this flushing operation, the ink in the nozzles can be discharged, so that thickening of the ink can be suppressed.
JP-A-9-52374

An ink receiving portion that receives ink ejected by flushing is provided outside the range of reciprocal movement during printing of the carriage.
For this reason, the carriage must move out of the reciprocating movement range during printing in order to perform flushing. Therefore, the moving distance of the carriage during flushing is long and the printing speed is reduced.
An object of the present invention is to shorten the moving distance of the carriage and prevent a decrease in printing speed.

  A main invention for achieving the above object includes a carriage for moving a nozzle for discharging liquid, reciprocating the carriage, discharging liquid from the nozzle reciprocating with the carriage, and discharging the liquid onto a medium. The present invention relates to a printing apparatus that performs printing on the medium by landing and performs a flushing operation for forcibly discharging the liquid from the nozzle so as not to land on the medium. In this printing apparatus, the flushing operation is performed within the range of reciprocal movement of the carriage when printing on the medium.

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

=== Summary of disclosure ===
At least the following matters will become clear from the description of the present specification and the accompanying drawings.

A carriage for moving a nozzle for discharging liquid;
Reciprocating the carriage, ejecting liquid from the nozzle reciprocating together with the carriage, landing the liquid on a medium, printing on the medium,
A printing apparatus that performs a flushing operation for forcibly discharging the liquid from the nozzle so as not to land on the medium,
A printing apparatus that performs the flushing operation within a range of reciprocal movement of the carriage when printing on the medium.
According to such a printing apparatus, the moving distance of the carriage can be shortened to prevent the printing speed from being lowered.

In this printing apparatus, it is preferable that the liquid forcedly ejected by the flushing operation is ejected to a liquid receiving portion provided within a range of reciprocal movement of the carriage.
According to such a printing apparatus, it is possible to prevent a decrease in printing speed.

In such a printing apparatus, when printing is performed without a margin on the edge of the medium, it is desirable that the liquid that has leaked from the medium land on the liquid receiving portion.
According to such a printing apparatus, the liquid receiving portion on which the liquid ejected by the flushing operation lands also serves as the liquid receiving portion on which the liquid leaked from the paper in the borderless printing lands.

In this printing apparatus, it is preferable that the flushing operation is performed while the carriage reciprocates once when printing on the medium.
According to such a printing apparatus, the flushing operation can be frequently performed by one reciprocating movement.

In this printing apparatus, it is preferable that the flushing operation is performed after the carriage starts to move until the liquid is ejected from the nozzles onto the medium.
According to such a printing apparatus, clogging of the nozzles can be reliably eliminated immediately before the dot formation process.

In such a printing apparatus, it is preferable that the flushing operation is performed after the carriage finishes ejecting the liquid from the nozzle until it stops.
According to such a printing apparatus, it is possible to eliminate clogging of nozzles that have not ejected ink during the dot formation process immediately before that.

In such a printing apparatus, it is preferable that at least two types of liquid droplets having different sizes are ejected from the nozzle, and the liquid droplet forcibly ejected by the flushing operation is a larger liquid droplet.
According to such a printing apparatus, if the ejected liquid droplet is large, the liquid droplet is surely landed on the liquid receiving portion, and there is no possibility that the liquid droplet is scattered.

In the printing apparatus, it is preferable that the plurality of nozzle rows provided in the moving direction of the carriage eject liquid to the liquid receiving portion at different timings.
According to such a printing apparatus, since each nozzle row discharges the liquid to the liquid receiving portion at a different timing, the width of the liquid receiving portion can be reduced.

The carriage for moving the nozzle that discharges the liquid is reciprocated, the liquid is ejected from the nozzle that reciprocates together with the carriage, the liquid is landed on the medium, and printing is performed on the medium.
A printing method for performing a flushing operation for forcibly discharging the liquid from the nozzle so as not to land on the medium,
A printing method, wherein the flushing operation is performed within a range of reciprocal movement of the carriage when printing on the medium.
According to such a printing method, the moving distance of the carriage can be shortened to prevent the printing speed from being lowered.

=== Configuration of Printing System ===
Next, an embodiment of a printing system (computer system) will be described with reference to the drawings. However, the description of the following embodiments includes embodiments relating to a computer program and a recording medium on which the computer program is recorded.

  FIG. 1 is an explanatory diagram showing an external configuration of a printing system. The printing system 100 includes a printer 1, a computer 110, a display device 120, an input device 130, and a recording / reproducing device 140. The printer 1 is a printing apparatus that prints an image on a medium such as paper, cloth, or film. The computer 110 is electrically connected to the printer 1 and outputs print data corresponding to the image to be printed to the printer 1 in order to cause the printer 1 to print an image. The display device 120 has a display and displays a user interface such as an application program or a printer driver. The input device 130 is, for example, a keyboard 130A or a mouse 130B, and is used for operating an application program, setting a printer driver, or the like along a user interface displayed on the display device 120. As the recording / reproducing device 140, for example, a flexible disk drive device 140A or a CD-ROM drive device 140B is used.

  A printer driver is installed in the computer 110. The printer driver is a program for realizing a function for displaying a user interface on the display device 120 and a function for converting image data output from an application program into print data. This printer driver is recorded on a recording medium (computer-readable recording medium) such as a flexible disk FD or a CD-ROM. Alternatively, the printer driver can be downloaded to the computer 110 via the Internet. In addition, this program is comprised from the code | cord | chord for implement | achieving various functions.

  The “printing apparatus” means the printer 1 in a narrow sense, but means a system of the printer 1 and the computer 110 in a broad sense.

=== Printer driver ===
<About the printer driver>
FIG. 2 is a schematic explanatory diagram of basic processing performed by the printer driver. The components already described are given the same reference numerals, and the description thereof is omitted.

  In the computer 110, computer programs such as a video driver 112, an application program 114, and a printer driver 116 operate under an operating system installed in the computer. The video driver 112 has a function of displaying, for example, a user interface on the display device 120 in accordance with a display command from the application program 114 or the printer driver 116. The application program 114 has a function of performing image editing, for example, and creates data related to an image (image data). The user can give an instruction to print an image edited by the application program 114 via the user interface of the application program 114. Upon receiving a print instruction, the application program 114 outputs image data to the printer driver 116.

  The printer driver 116 receives image data from the application program 114, converts the image data into print data, and outputs the print data to the printer. Here, the print data is data in a format that can be interpreted by the printer 1, and is data having various command data and pixel data. Here, the command data is data for instructing the printer to execute a specific operation. The pixel data is data relating to pixels constituting an image to be printed (printed image). For example, data relating to dots formed at positions on the paper corresponding to a certain pixel (such as dot color and size). Data).

  The printer driver 116 performs resolution conversion processing, color conversion processing, halftone processing, rasterization processing, and the like in order to convert image data output from the application program 114 into print data. Hereinafter, various processes performed by the printer driver 116 will be described.

  The resolution conversion process is a process of converting image data (text data, image data, etc.) output from the application program 114 into a resolution for printing on paper. For example, when the resolution for printing an image on paper is specified as 720 × 720 dpi, the image data received from the application program 114 is converted into image data having a resolution of 720 × 720 dpi. Note that the image data after the resolution conversion process is multi-gradation (for example, 256 gradations) RGB data represented by an RGB color space. Hereinafter, RGB data obtained by performing resolution conversion processing on image data is referred to as RGB image data.

  The color conversion process is a process for converting RGB data into CMYK data represented by a CMYK color space. The CMYK data is data corresponding to the ink color of the printer. This color conversion processing is performed by the printer driver 116 referring to a table (color conversion lookup table LUT) in which gradation values of RGB image data and gradation values of CMYK image data are associated with each other. Through this color conversion process, RGB data for each pixel is converted into CMYK data corresponding to the ink color. The data after the color conversion processing is CMYK data with 256 gradations represented by the CMYK color space. Hereinafter, CMYK data obtained by performing color conversion processing on RGB image data is referred to as CMYK image data.

  The halftone process is a process for converting high gradation number data into gradation number data that can be formed by a printer. For example, data representing 256 gradations is converted into 1-bit data representing 2 gradations or 2-bit data representing 4 gradations by halftone processing. In the halftone process, pixel data is created by using a dither method, γ correction, error diffusion method, or the like so that the printer can form dots dispersedly. When performing halftone processing, the printer driver 116 refers to a dither table when performing a dither method, refers to a gamma table when performing γ correction, and refers to a diffused error when performing an error diffusion method. Refer to the error memory for storage. The data subjected to the halftone process has a resolution (for example, 720 × 720 dpi) equivalent to the RGB data described above. The halftoned data is composed of 1-bit or 2-bit data for each pixel, for example. Hereinafter, of the halftone processed data, 1-bit data is referred to as binary data, and 2-bit data is referred to as multi-value data.

  The rasterization process is a process of changing matrix image data in the order of data to be transferred to the printer. The rasterized data is output to the printer as pixel data included in the print data.

<About printer driver settings>
FIG. 3 is an explanatory diagram of the user interface of the printer driver. The user interface of this printer driver is displayed on the display device via the video driver 112. The user can make various settings of the printer driver using the input device 130.

  The user can select a print mode from this screen. For example, the user can select the high-speed print mode or the fine print mode as the print mode. Then, the printer driver converts the image data into print data so as to have a format corresponding to the selected print mode.

  Further, the user can select the printing resolution (dot interval when printing) from this screen. For example, the user can select 720 dpi or 360 dpi as the print resolution from this screen. Then, the printer driver performs resolution conversion processing according to the selected resolution, and converts the image data into print data.

  Further, the user can select a printing paper used for printing from this screen. For example, the user can select plain paper or glossy paper as the printing paper. If the paper type (paper type) is different, the ink bleeding and drying methods are also different, so the ink amount suitable for printing also differs. Therefore, the printer driver converts the image data into print data according to the selected paper type.

  As described above, the printer driver converts the image data into print data in accordance with conditions set via the user interface. The user can make various settings of the printer driver from this screen, and can also know the remaining amount of ink in the cartridge.

=== Configuration of Printer ===
<Inkjet printer configuration>
FIG. 4 is a block diagram of the overall configuration of the printer of this embodiment. FIG. 5 is a schematic diagram of the overall configuration of the printer of this embodiment. FIG. 6 is a cross-sectional view of the overall configuration of the printer of this embodiment. Hereinafter, the basic configuration of the printer of this embodiment will be described.

  The printer of this embodiment includes a transport unit 20, a carriage unit 30, a head unit 40, a detector group 50, and a controller 60. The printer 1 that has received print data from the computer 110, which is an external device, controls each unit (the conveyance unit 20, the carriage unit 30, and the head unit 40) by the controller 60. The controller 60 controls each unit based on the print data received from the computer 110 and forms an image on paper. The situation in the printer 1 is monitored by a detector group 50, and the detector group 50 outputs a detection result to the controller 60. The controller 60 that receives the detection result from the detector group 50 controls each unit based on the detection result.

  The transport unit 20 is for feeding a medium (for example, the paper S) to a printable position and transporting the paper by a predetermined transport amount in a predetermined direction (hereinafter referred to as a transport direction) during printing. That is, the transport unit 20 functions as a transport mechanism (transport means) that transports paper. The transport unit 20 includes a paper feed roller 21, a transport motor 22 (also referred to as a PF motor), a transport roller 23, a platen 24, and a paper discharge roller 25. However, in order for the transport unit 20 to function as a transport mechanism, all of these components are not necessarily required. The paper feed roller 21 is a roller for automatically feeding the paper inserted into the paper insertion slot into the printer. The paper feed roller 21 has a D-shaped cross section, and the length of the circumferential portion is set to be longer than the transport distance to the transport roller 23. 23 can be conveyed. The transport motor 22 is a motor for transporting paper in the transport direction, and is constituted by a DC motor. The transport roller 23 is a roller that transports the paper S fed by the paper feed roller 21 to a printable area, and is driven by the transport motor 22. The platen 24 supports the paper S being printed. The paper discharge roller 25 is a roller for discharging the printed paper S to the outside of the printer. The paper discharge roller 25 rotates in synchronization with the transport roller 23.

  The carriage unit 30 is for moving (also referred to as “scanning”) the head in a predetermined direction (hereinafter referred to as a moving direction). The carriage unit 30 includes a carriage 31 and a carriage motor 32 (also referred to as a CR motor). The carriage 31 can reciprocate in the moving direction. (Thus, the head moves along the moving direction.) In addition, the carriage 31 detachably holds an ink cartridge 90 that stores ink. The carriage motor 32 is a motor for moving the carriage 31 in the movement direction, and is constituted by a DC motor.

  The head unit 40 is for ejecting ink onto paper. The head unit 40 has a head 41. The head 41 has a plurality of nozzles that are ink discharge portions, and discharges ink intermittently from each nozzle. The head 41 is provided on the carriage 31. Therefore, when the carriage 31 moves in the movement direction, the head 41 also moves in the movement direction. Then, by intermittently ejecting ink while the head 41 is moving in the moving direction, dot lines (raster lines) along the moving direction are formed on the paper.

  The detector group 50 includes a linear encoder 51, a rotary encoder 52, a paper detection sensor 53, an optical sensor 54, and the like. The linear encoder 51 is for detecting the position of the carriage 31 in the moving direction. The rotary encoder 52 is for detecting the rotation amount of the transport roller 23. The paper detection sensor 53 is for detecting the position of the leading edge of the paper to be printed. The paper detection sensor 53 is provided at a position where the position of the leading edge of the paper can be detected while the paper feed roller 21 feeds the paper toward the transport roller 23. The paper detection sensor 53 is a mechanical sensor that detects the leading edge of the paper by a mechanical mechanism. More specifically, the paper detection sensor 53 has a lever that can rotate in the transport direction, and this lever is disposed so as to protrude into the paper transport path. For this reason, since the leading edge of the paper comes into contact with the lever and the lever is rotated, the paper detection sensor 53 detects the position of the leading edge of the paper by detecting the movement of the lever. The optical sensor 54 is attached to the carriage 31. The optical sensor 54 detects the presence or absence of paper by the light receiving unit detecting reflected light of light irradiated on the paper from the light emitting unit. The optical sensor 54 detects the position of the edge of the paper while being moved by the carriage 31. Since the optical sensor 54 optically detects the edge of the paper, the detection accuracy is higher than that of the mechanical paper detection sensor 53.

  The controller 60 is a control unit (control means) for controlling the printer. The controller 60 includes an interface unit 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface unit 61 is for transmitting and receiving data between the computer 110 which is an external device and the printer 1. The CPU 62 is an arithmetic processing unit for controlling the entire printer. The memory 63 is for securing an area for storing the program of the CPU 62, a work area, and the like, and has storage means such as a RAM and an EEPROM. The CPU 62 controls each unit via the unit control circuit 64 in accordance with a program stored in the memory 63.

<About printing operation>
FIG. 7 is a flowchart of processing during printing. Each process described below is executed by the controller 60 controlling each unit in accordance with a program stored in the memory 63. This program has a code for executing each process.

  Print command reception (S001): First, the controller 60 receives a print command from the computer 110 via the interface unit 61. This print command is included in the header of print data transmitted from the computer 110. Then, the controller 60 analyzes the contents of various commands included in the received print data, and performs the following paper feed processing, transport processing, ink ejection processing, and the like using each unit.

  Paper Feed Process (S002): The paper feed process is a process for supplying paper to be printed into the printer and positioning the paper at a print start position (also referred to as a cue position). The controller 60 rotates the paper feed roller 21 and sends the paper to be printed to the transport roller 23. The controller 60 rotates the transport roller 23 to position the paper fed from the paper feed roller 21 at the print start position. When the paper is positioned at the print start position, at least some of the nozzles of the head 41 are opposed to the paper.

  Dot Forming Process (S003): The dot forming process is a process for forming dots on paper by intermittently ejecting ink from a head that moves in the moving direction. The controller 60 drives the carriage motor 32 to move the carriage 31 in the movement direction. Then, the controller 60 ejects ink from the head based on the print data while the carriage 31 is moving. When ink droplets ejected from the head land on the paper, dots are formed on the paper. Since ink is intermittently ejected from the moving head, a dot row composed of a plurality of dots along the moving direction is formed on the paper.

  Conveyance process (S004): The conveyance process is a process of moving the paper relative to the head in the conveyance direction. The controller 60 drives the carry motor and rotates the carry roller to carry the paper in the carrying direction. By this carrying process, the head 41 can form dots at positions different from the positions of the dots formed by the previous dot formation process.

  Paper discharge determination (S005): The controller 60 determines whether or not to discharge the paper being printed. If data to be printed remains on the paper being printed, no paper is discharged. Then, the controller 60 alternately repeats the dot formation process and the conveyance process until there is no more data to be printed, and gradually prints an image composed of dots on paper.

  Paper Discharge Process (S006): When there is no more data to be printed on the paper being printed, the controller 60 discharges the paper by rotating the paper discharge roller. The determination of whether or not to discharge paper may be based on a paper discharge command included in the print data.

  Print end determination (S007): Next, the controller 60 determines whether or not to continue printing. If printing is to be performed on the next paper, printing is continued and the paper feeding process for the next paper is started. If printing is not performed on the next paper, the printing operation is terminated.

<About nozzle>
FIG. 8 is an explanatory diagram showing the arrangement of nozzles on the lower surface of the head 41. On the lower surface of the head 41, a black ink nozzle group K, a cyan ink nozzle group C, a magenta ink nozzle group M, and a yellow ink nozzle group Y are formed. Each nozzle group includes a plurality of nozzles (180 in this embodiment) that are ejection openings for ejecting ink of each color.

  The plurality of nozzles of each nozzle group are aligned at a constant interval (nozzle pitch: k · D) along the transport direction. Here, D is the minimum dot pitch in the carrying direction (that is, the interval at the highest resolution of dots formed on the paper S). K is an integer of 1 or more. For example, when the nozzle pitch is 180 dpi (1/180 inch) and the dot pitch in the transport direction is 720 dpi (1/720), k = 4.

  The nozzles in each nozzle group are assigned a lower number in the downstream nozzle (# 1 to # 180). That is, the nozzle # 1 is located downstream of the nozzle # 180 in the transport direction. Each nozzle is provided with a piezo element (not shown) as a drive element for driving each nozzle to eject ink droplets. Further, the optical sensor 54 is substantially at the same position as the nozzle # 180 on the most upstream side with respect to the position in the paper transport direction.

=== Borderless printing ===
<Print data for borderless printing>
FIG. 9 is an explanatory diagram of print data at the time of borderless printing. In “borderless printing”, printing is performed on the entire surface of the paper. By this “marginless printing”, ink can be ejected and printed without margins on the four edges of the paper, so that an output result of the same image as a photograph can be obtained. For this reason, inkjet printers capable of “borderless printing” have recently gained popularity.
In the figure, the inner solid square represents the size of the paper. In the figure, the outer dotted dotted rectangle indicates the size of the print data. In borderless printing, ink is ejected to a larger area than paper and printing is performed on the entire surface of the paper. Therefore, the size of the print data is larger than the size of the paper. Therefore, the printer ejects ink outside the paper range.

<About protrusions and grooves>
FIG. 10A is an explanatory diagram of ink ejection during borderless printing. FIG. 10B is an explanatory diagram of ink landing during borderless printing. Since the components already described are given the same reference numerals, the description thereof is omitted.

  Ink droplets Ip are ejected from the nozzles of the head 41, the ejected ink droplets Ip land on the paper S, and dots D constituting an image to be printed on the paper S are formed. In the case of borderless printing, as described above, the print data corresponds to a range larger than the paper size. Therefore, if ink is ejected from the nozzles based on this print data, a portion of the ejected ink does not land on the paper S but land on the platen 24. However, if the ink landed on the platen 24 adheres to the back side of the paper, the paper becomes dirty, which is not desirable. Therefore, in order to prevent stains on the back side of the paper, the printer platen 24 that performs borderless printing includes a protrusion 242 (also referred to as a convex portion or a rib), a groove portion 244 (also referred to as a concave portion), and an absorbing member 246. Yes.

  The protrusions 242 are members that come into contact with the paper when the platen 24 supports the paper S. The protrusion 242 is configured so that the paper does not contact the groove 244. The protrusions 242 are provided at positions where ink droplets do not land during borderless printing. This is because if the protrusion 242 is stained with ink, the back surface of the paper is stained. Therefore, for example, the protrusion 242 is not provided at a position that protrudes from the right end of the paper in the drawing. If the central portion of the protrusion 242 supports the right edge of the paper, or if the protrusion 242 is provided in the ink leakage region, the protrusion 242 may be stained with ink during borderless printing. By the way, since the right edge of the paper is guided by a fixed guide, the position in the scanning direction of the right edge of the paper at the time of printing (the position of the right edge of the paper S in the figure) is what width of the paper. But it is decided in the same way. For this reason, the position of the protrusion 242 is determined based on the position of the fixed guide 82. Further, the width of the paper to be printed (the length of the paper in the scanning direction) is determined to a prescribed size. For example, if the paper is A4 size, the width of the paper is 210 mm, and if it is a postcard, the width of the paper is 100 mm. Therefore, the protrusions 242 are provided so as not to be located in the ink leakage region during borderless printing, regardless of the paper of any specified size.

  The paper S shown in the drawing is a postcard which is the paper having the smallest width among the papers transported by the transport unit (papers that can be printed by the printer 1). The transport unit also transports paper having a width larger than the postcard (the printer transports paper having a width larger than the postcard). Therefore, a protrusion 242 for supporting a paper larger than the paper S is also present on the left side of the protrusion 242 for supporting the paper S in the drawing.

  The groove portion 244 is a recess provided in the platen 24. Since the groove portion 244 is recessed with respect to the protrusion 242, even if the groove portion 244 is soiled with ink, the back surface of the paper is not soiled. For this reason, the groove portion 244 is configured such that ink at the time of borderless printing that has not landed on the paper land on the groove portion 244. In other words, the area where ink is leaked during borderless printing (leakage area) is positioned in the groove 244.

  The absorbing member 246 is a member for absorbing ink, and is composed of, for example, a water-absorbing sponge. The absorbing member 246 is provided in the groove 244. The absorbing member 246 absorbs ink that has landed on the groove 244 during borderless printing. Absorption of ink by the absorbing member 246 prevents the leaked ink from being dispersed. As described above, since the printer can print on a plurality of papers having different widths, an absorbing member 246 is provided in a leakage area corresponding to the paper of a specified size that can be printed (left side in the figure). Also, it is shown that an absorbing member for paper other than postcards (for example, A4 size paper or the like) is provided).

=== Flushing operation ===
The “flushing” operation is an operation for forcibly ejecting ink so as not to land on a medium (paper, cloth, OHP sheet, etc.) and ejecting the ink to an ink receiving portion. By performing the flushing operation, it is possible to discharge the ink in the nozzles that are not in use, and thus it is possible to suppress the increase in the viscosity of the ink. This flushing operation is performed at a predetermined timing (for example, once every several tens of seconds or once every several dot forming processes).

<About the flushing operation of the reference example>
11A to 11D are explanatory diagrams of the flushing operation of the reference example. FIG. 11A is an explanatory diagram showing the stop position of the carriage 31 before the dot formation process. FIG. 11B is an explanatory diagram of ink landing during printing. FIG. 11C is an explanatory diagram showing the stop position of the carriage 31 after the dot formation processing. FIG. 11D is an explanatory diagram of the flushing operation of the carriage 31. Since the components already described are given the same reference numerals, the description thereof is omitted.

  During the dot formation process (FIG. 7, S003), the carriage 31 operates as follows. First, before performing the dot formation process, the carriage 31 stops at a position outside the right end of the paper (a position where the lower surface of the head 41 does not face the paper S) as shown in FIG. 11A. The carriage 31 accelerates toward the left in the figure and moves at a constant speed at a predetermined speed. Then, when the carriage 31 is moving at a constant speed, ink ejection is started from the nozzles of the head 41 so as to land on the paper S as shown in FIG. 11B. When the ink ejection is finished and the dot formation process is finished, the carriage 31 decelerates. Then, as shown in FIG. 11C, the carriage 31 stops at a position outside the left end of the paper (a position where the lower surface of the head 41 does not face the paper S).

  When the dot formation process is repeatedly performed, the carriage 31 returns from the stop position in FIG. 11C and moves toward the right in the figure to perform the dot formation process. When the dot formation process is finished, the ink ejection is finished, the carriage 31 decelerates, and stops at the stop position in FIG. 11A. Thus, when the dot forming process is repeatedly performed, the carriage 31 reciprocates between the stop position of FIG. 11A and the stop position of FIG. 11C.

In the reference example, the ink receiving portion 301 is provided outside the range of reciprocal movement of the carriage during the dot formation process (see FIGS. 11A to 11D). The ink receiving portion 301 is provided with an absorbing member 247 for absorbing ink ejected by the flushing operation.
In the reference example, when the flushing operation is performed, the carriage 31 must move to the ink receiving portion 301 provided outside the carriage reciprocation range during the dot formation process. For this reason, if a flushing operation is performed during printing, the printing speed is reduced.

<About the flushing operation within the reciprocating range of the carriage of this embodiment>
12A to 12E are explanatory diagrams of the flushing operation of the carriage 31 of this embodiment. FIG. 12A is an explanatory diagram showing the stop position of the carriage 31 before the dot formation process. FIG. 12B is an explanatory diagram of a flushing operation performed between the start of movement of the carriage 31 and the ejection of ink from the head onto the paper. FIG. 12C is an explanatory diagram of ink landing during printing. FIG. 12D is an explanatory diagram of the flushing operation performed between the end of ejecting ink from the head and the stop of the carriage 31. FIG. 12E is an explanatory diagram showing the stop position of the carriage 31 after the dot formation processing. Since the components already described are given the same reference numerals, the description thereof is omitted.

  In this embodiment, as shown in FIGS. 12A to 12E, the ink receiving portion 301 as in the reference example is not provided. On the other hand, in the present embodiment, as in the reference example, a groove portion 244 is provided in the range of reciprocal movement of the carriage 31 during the dot formation process. In this embodiment, the ink ejected by the flushing operation is landed on the groove portion where the ink leaked from the paper is landed in the borderless printing. That is, in this embodiment, instead of the ink receiving portion 301 of the reference example, the groove portion 244 on which ink leaked by borderless printing lands also serves as an ink receiving portion on which ink ejected by the flushing operation lands. .

  The absorbing member 246 of this embodiment has a higher water absorption than the absorbing member 246 of the reference example that absorbs ink that has leaked from paper in borderless printing. This is because the absorbing member 246 of the present embodiment not only absorbs ink that has leaked from paper in borderless printing, but also absorbs ink that is ejected by a flushing operation.

  In the present embodiment, during the dot formation process (FIG. 7, S003), the carriage 31 operates as follows. Before performing the dot formation process, the carriage 31 stops at a position outside the right side of the paper (a position where the lower surface of the head 41 does not face the paper S) as shown in FIG. 12A. The carriage 31 accelerates toward the left in the drawing. After the carriage 31 starts to move, before the ink is ejected so as to land on the paper from the nozzles of the head 41 (while the carriage is accelerating), as shown in FIG. 12B, the ink is landed on the groove 244. The flushing operation is performed by forcibly discharging. When the flushing operation is completed, the carriage 31 moves at a constant speed, and as shown in FIG. 12C, ink is ejected from the head during the constant speed movement to perform dot formation processing. When the dot formation process is completed, the carriage 31 decelerates. Then, from the end of the ejection of ink for landing on the paper until the carriage 31 stops (while the carriage is decelerating), as shown in FIG. Flushing operation is performed to land. When the flushing operation is finished, as shown in FIG. 12E, the carriage 31 stops at a position outside the left end of the paper (a position where the lower surface of the head 41 does not face the paper S).

  The carriage 31 can return from the stop position in FIG. 12E and repeatedly perform the dot formation process as described above. When the dot formation process is repeatedly performed, the carriage 31 reciprocates between the stop position in FIG. 12A and the stop position in FIG. 12E. In this embodiment, the flushing operation can be performed during one reciprocating movement. As described above, in the present embodiment, the printing speed is not reduced by the flushing operation, so that the flushing operation can be frequently performed even during printing.

  As described above, if the flushing operation is performed after the carriage starts moving until ink for landing on the paper is ejected, nozzle clogging can be eliminated immediately before the dot formation process. The image quality of the printed image is improved. For this reason, it is desirable that the flushing operation at this time forcibly ejects ink from all the nozzles.

  In the present embodiment, the flushing operation is also performed after the ejection of ink for landing on the paper is finished and before the carriage 31 is stopped. In the flushing operation at this time, in order to suppress ink consumption, ink may be ejected from nozzles that have not ejected ink during the dot forming process immediately before that. (However, ink may be ejected from all nozzles.)

  In the present embodiment, ink is ejected into the groove 244 provided in the reciprocating movement range of the carriage 31 during the dot formation process, and the flushing operation is performed. Therefore, even when the flushing operation is performed during printing, the groove portion 244 is provided within the reciprocating movement range of the carriage 31, so that a decrease in printing speed can be prevented.

<About the timing when the nozzles eject ink>
In the reference example, the carriage 31 is stopped when ink is ejected to the ink receiving portion 301 and the flushing operation is performed. For this reason, the width of the ink receiving portion 301 must be the same as or wider than the width of the head 41.
In the present embodiment, as shown in FIGS. 12B and 12D, when the carriage 31 is moving, the plurality of nozzle rows provided in the movement direction of the carriage 31 are moved at different timings in the nozzle rows. In order from the front, the flushing operation is performed by discharging ink into the groove. For example, when the carriage 31 moves in the left direction in the figure, the flushing operation is performed in order from the left nozzle row. As a result, the width of the groove 244 can be made narrower than the width of the head 41, so that the width of the groove 244 can be reduced.

<Amount of ejected ink droplets>
The ink droplets forcibly ejected by the flushing operation land on the groove. However, when the ink droplet is small, the flying distance of the ink from the head to the groove portion is long, so that the ink droplet may be scattered due to air resistance before the ink reaches the groove portion. For this reason, if at least two types of ink droplets having different sizes can be ejected from the nozzle, it is preferable to eject the larger one of the ink droplets that are forcibly ejected by the flushing operation.

=== Other Embodiments ===
Moreover, although the printer etc. as one embodiment were demonstrated, said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

  In the above-described embodiment, the ink that has leaked from the paper during borderless printing and the ink that is ejected during the flushing operation land on the same groove (ink receiving portion). However, it is not limited to this. For example, the ink receiving portion on which the ink ejected by the flushing operation lands may be provided separately instead of using the ink receiving portion on which the ink leaked by the borderless printing lands. Even in this case, if the flushing operation is performed within the reciprocating range of the carriage during printing, it is possible to prevent a decrease in printing speed. Further, as in the reference example, there may be an ink receiver outside the reciprocal movement range of the carriage. However, as in the above-described embodiment, the configuration of the apparatus can be simplified if the ink receiving portion on which the ink ejected by the flushing operation lands also serves as the ink receiving portion on which the ink leaked by borderless printing lands. .

  In the above-described embodiment, the flushing operation is performed while the carriage is reciprocated once when printing on paper. However, it is not limited to this. For example, the flushing operation may be performed while the carriage reciprocates one or more times. Even in this case, if the flushing operation is performed within the reciprocating range of the carriage during printing, it is possible to prevent a decrease in printing speed. However, as in the above-described embodiment, if the flushing operation is performed while the carriage is reciprocated once, the flushing operation is frequently performed, and thus it is possible to suppress ink thickening.

  In the above-described embodiment, at least two types of ink droplets having different sizes can be ejected from the nozzle, and the ink droplet forcibly ejected by the flushing operation is the larger ink droplet. However, it is not limited to this. Even if the ink droplet forcibly ejected by the flushing operation is the smaller one, the increase in the viscosity of the ink can be suppressed. However, if the ink droplet is large, there is no possibility of the ink droplet scattering.

  In the above-described embodiment, the plurality of nozzle rows provided in the carriage movement direction ejects ink to the ink receiving portion at different timings. However, it is not limited to this. For example, all the nozzle rows may eject ink simultaneously during the flushing operation. However, in this case, it is necessary to provide an ink receiving portion having a width larger than the width of the head as in the reference example. On the other hand, if each nozzle row ejects ink to the ink receiving portion at different timings as in the above-described embodiment, the width of the ink receiving portion can be made smaller than the width of the head, and the ink receiving portion can be made smaller. be able to.

  In the above-described embodiment, the flushing operation is performed while the carriage is moving. However, it is not limited to this. The flushing operation may be performed when the carriage is stopped at the return position of the reciprocating movement. However, in this case, it is necessary to provide an ink receiving portion having a width larger than the width of the head as in the reference example.

It is explanatory drawing of the whole structure of a printing system. FIG. 6 is an explanatory diagram of basic processing performed by a printer driver. 3 is an explanatory diagram of a user interface of a printer driver. FIG. 1 is a block diagram of an overall configuration of a printer. 1 is a schematic diagram of an overall configuration of a printer. 1 is a cross-sectional view of the overall configuration of a printer. It is a flowchart of the process at the time of printing. It is explanatory drawing which shows the arrangement | sequence of a nozzle. It is explanatory drawing of the printing data at the time of borderless printing. FIG. 10A is an explanatory diagram of ink ejection during borderless printing. FIG. 10B is an explanatory diagram of ink landing during borderless printing. FIG. 11A is an explanatory diagram showing the stop position of the carriage 31 before the dot formation process. FIG. 11B is an explanatory diagram of ink landing during printing. FIG. 11C is an explanatory diagram showing the stop position of the carriage 31 after the dot formation processing. FIG. 11D is an explanatory diagram of the flushing operation of the carriage 31. FIG. 12A is an explanatory diagram showing the stop position of the carriage 31 before the dot formation process. FIG. 12B is an explanatory diagram of a flushing operation performed between the start of movement of the carriage 31 and the ejection of ink from the head onto the paper. FIG. 12C is an explanatory diagram of ink landing during printing. FIG. 12D is an explanatory diagram of the flushing operation performed between the end of ejecting ink from the head and the stop of the carriage 31. FIG. 12E is an explanatory diagram showing the stop position of the carriage 31 after the dot formation processing.

Explanation of symbols

1 printer,
20 transport unit, 21 paper feed roller, 22 transport motor,
23 transport roller, 24 platen, 25 discharge roller,
30 Carriage unit, 31 Carriage, 32 Carriage motor,
40 head units, 41 heads,
50 detector groups, 51 linear encoder, 52 rotary encoder,
53 Paper detection sensor, 54 Optical sensor,
60 controller, 61 interface unit, 62 CPU,
63 memory, 64 unit control circuit, 90 ink cartridge,
100 systems, 110 computers, 112 video drivers,
114 application programs, 116 printer drivers,
120 display device,
130 input device, 130A keyboard, 130B mouse,
140 recording / reproducing apparatus, 140A flexible disk drive apparatus,
140B CD-ROM drive device,
242 protrusion, 244 groove,
246 Absorbing member, 247 Absorbing member 301 Ink receiving portion

Claims (10)

A carriage for moving a nozzle for discharging liquid;
Reciprocating the carriage, ejecting liquid from the nozzle reciprocating together with the carriage, landing the liquid on a medium, printing on the medium,
A printing apparatus that performs a flushing operation for forcibly discharging the liquid from the nozzle so as not to land on the medium,
A printing apparatus that performs the flushing operation within a range of reciprocal movement of the carriage when printing on the medium. The printing apparatus according to claim 1,
The printing apparatus, wherein the liquid forcibly discharged by the flushing operation is discharged to a liquid receiving portion provided within a range of reciprocation of the carriage. The printing apparatus according to claim 2,
When printing without margins on the edge of the medium, the liquid leaked from the medium lands on the liquid receiving portion. The printing apparatus according to any one of claims 1 to 3,
The printing apparatus according to claim 1, wherein the flushing operation is performed while the carriage reciprocates once when printing on the medium. The printing apparatus according to any one of claims 1 to 3,
The printing apparatus, wherein the flushing operation is performed after the carriage starts moving until the liquid is ejected from the nozzle to the medium. The printing apparatus according to any one of claims 1 to 3,
The printing apparatus, wherein the flushing operation is performed after the carriage finishes ejecting the liquid from the nozzle until it stops. The printing apparatus according to any one of claims 1 to 6,
A printing apparatus, wherein at least two types of liquid droplets having different sizes are ejected from the nozzle, and the liquid droplet forcibly ejected by the flushing operation is a larger liquid droplet. The printing apparatus according to any one of claims 1 to 7,
The printing apparatus according to claim 1, wherein the plurality of nozzle rows provided in the moving direction of the carriage eject liquid at different timings. A carriage for moving a nozzle for discharging liquid;
Reciprocating the carriage, ejecting liquid from the nozzle reciprocating together with the carriage, landing the liquid on a medium, printing on the medium,
A printing apparatus that performs a flushing operation for forcibly discharging the liquid from the nozzle so as not to land on the medium,
Performing the flushing operation within the range of reciprocal movement of the carriage when printing on the medium;
The liquid forcibly discharged by the flushing operation is discharged to a liquid receiving portion provided within a range of reciprocation of the carriage,
When printing without margins on the edge of the medium, the liquid that has leaked from the medium has landed on the liquid receiving portion,
The flushing operation is performed while the carriage reciprocates once when printing on the medium.
The flushing operation is performed after the carriage starts moving until the liquid is discharged from the nozzle to the medium.
The flushing operation is performed after the carriage finishes discharging the liquid from the nozzle until it stops.
At least two types of liquid droplets having different sizes are ejected from the nozzle, and the liquid droplet forcibly ejected by the flushing operation is a larger liquid droplet,
The printing apparatus according to claim 1, wherein the plurality of nozzle rows provided in the movement direction of the carriage eject liquid to the liquid receiving portion at different timings. The carriage for moving the nozzle that discharges the liquid is reciprocated, the liquid is ejected from the nozzle that reciprocates together with the carriage, the liquid is landed on the medium, and printing is performed on the medium.
A printing method for performing a flushing operation for forcibly discharging the liquid from the nozzle so as not to land on the medium,
A printing method, wherein the flushing operation is performed within a range of reciprocal movement of the carriage when printing on the medium.

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