JP2007001263A - Printer and cuing method of printing media - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable it to perform cuing of printing media as correctly as possible. <P>SOLUTION: A printer 100 controls the conveyance volume of the printing media after the conveyed printing media is detected by a printing media sensor 213, prints a plurality of marks in positions where the transfer directions of the printing media P differ, and specifies the mark corresponding to the cued position from the plurality of the marks by printing the plurality of the marks in the positions where the transfer directions of the printing media P on the printing media P is conveyed according to the controlled conveyance volume. The printer 100 performs the cuing of the printing media by conveying the printing media by the conveyance volume compensated based on the correction value corresponding to the specified mark. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique for accurately cuing a print medium.

  In printing, the print media (for example, paper, OHP film, CD (Compact Disk), DVD (Digital Versatile Disk), etc.) is accurately cued, for example, the leading edge of the print media is at the specified transport start position. It is required to accurately convey print media so that they overlap. As a technique for accurately cuing a print medium, for example, a technique disclosed in Patent Document 1 is known. In Patent Document 1, the image scanner 9 is mounted on the carriage 4, the leading edge of the recording medium P is detected by the image scanner 9, and the downstream edge of the platen 2 in the recording medium conveyance direction and the leading edge of the recording medium P are the same. The width between the side portion and the width between the downstream side edge of the platen 2 in the recording medium conveyance direction and the other side portion of the leading edge side of the recording medium P are obtained, and the average value is compared with the logical conveyance value. Depending on the difference, control is performed to adjust the transport amount of the recording start line of the recording medium P to the recording unit and transport it.

JP-A-11-170640 (for example, abstract)

  Ensuring that the print medium can be conveyed to a predetermined cueing position as accurately as possible is an important factor for ensuring that printing is performed at an accurate position on the print medium.

  Accordingly, an object of the present invention is to enable the cueing of a print medium as accurately as possible.

  Other objects of the present invention will become clear from the following description.

  The printer according to the first aspect of the present invention includes a transport unit that transports a print medium, a print media sensor that detects the transported print medium, and a front end of the print medium that is detected by the print media sensor. A plurality of conveyance control means for controlling the conveyance means to convey the print medium to a predetermined position; and a position on the print medium that is different in the conveyance direction of the print medium including the predetermined position. Mark printing means for printing the mark, mark specifying means for specifying a mark corresponding to the cueing position from the tip, and storage means for storing a correction value corresponding to the specified mark. The printer corrects the transport amount from the front end with the stored correction value, and transports the print medium with the transport amount after the correction, thereby transporting the print medium to the heading position.

  Here, the correction of the conveyance amount may be a direct correction (for example, the conveyance amount for cueing itself is corrected with the stored correction value) or an indirect correction (for example, The transport amount may be corrected by correcting the target position at the front end of the print medium with the correction value).

  Further, the “specified position” may be a stop position when the print medium is conveyed by a specified conveyance amount after the leading edge of the print medium is detected, for example. Therefore, when the print media is transported accurately, the specified position matches the cue position described later. For example, the print media is tilted or there is an error in the mounting position of the print media sensor. If it occurs, the specified position does not match the cue position described later.

  The “cue position” can be a stop position when the transport amount is corrected so as to stop at the desired stop position from the front end of the print medium.

  In one embodiment, the printer may further include a print head having a plurality of dot forming elements along the transport direction. The mark printing unit prints the plurality of marks on the print medium while moving the print head in a main scanning direction orthogonal to the transport direction and changing a dot forming element used in each of the plurality of marks. be able to. In this case, the plurality of marks can be printed at different positions in the main scanning direction, and the print medium can be prevented from being conveyed during the printing. Each of the plurality of marks may overlap at least a part with other marks in the main scanning direction.

  In one embodiment, the correction value stored in the storage unit may be obtained based on the calculated degree of inclination and the position of the specified mark.

  In one embodiment, the correction value stored in the storage unit is obtained based on the calculated inclination degree, the transport direction position of the identified mark, and the main scanning direction position. Also good.

  In one embodiment, the printer may include a media conveyance amount calculation unit that calculates a conveyance amount of the print media. The printer uses the media conveyance amount calculation means to calculate respective distances from a predetermined reference line, which are set downstream in the conveyance direction and in the main scanning direction, to two points along the tip detected by the print media sensor. Can be sought. In this case, the inclination degree can be calculated based on the distance.

  Note that at least the “conveyance amount” of the print medium here is a substantial media conveyance amount (for example, the number of encoder steps linked to the conveyance motor, or correction based on the number of steps (for example, correction for each paper type)). Etc.), and not the target transport amount for motor control. That is, the “conveyance amount” here can be a result value, not a target value.

  In one embodiment, the mark specified by the mark specifying means is a state in which a transparent sheet on which a reference mark is printed at the specified position is overlaid on a print medium on which the plurality of marks are printed. It can be an input mark. Specifically, for example, the mark specified by the mark specifying means is information input via a user interface such as an operation button or a touch panel, and is used to specify a mark that overlaps or is closest to the reference mark. Information (for example, ID of the mark) can be used. In addition, the mark specified by the mark specifying means is input from a data source device (for example, an image scanner or an external memory) as a read image obtained by scanning an image obtained by superimposing the transparent sheet on the print medium. It may be a mark specified by analyzing the input image.

  In one embodiment, the mark specified by the mark specifying means may be a mark specified by detecting positions of the plurality of marks with the print media sensor. Specifically, for example, the print media sensor is an image sensor such as a CCD (Charge Coupled Devices), and corresponds to at least the prescribed position of the plurality of marks from the front end of the print media by the image sensor. By detecting an image in a range including the mark to be detected and analyzing the detected image, the mark corresponding to the specified position can be specified.

  According to the present invention, a plurality of marks are printed at different positions in the transport direction on the print medium, and a mark corresponding to the specified position is specified from the plurality of marks. Then, when the print media is cued, the print media is cued by carrying with the carry amount corrected with the correction value corresponding to the specified mark. Therefore, the print medium can be accurately conveyed to a predetermined cueing position.

  Hereinafter, some embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram for explaining a portion related to conveyance of a print medium in the printer according to the first embodiment of the present invention.

  The printer 100 is, for example, a serial printer. Specifically, the printer 100 is, for example, an inkjet printer that prints an image on a print medium P (recording material) by an inkjet method. The printer 100 is fed with a supply roller 14 for taking the print medium P into the printer 100 and a carry roller 19 for carrying the print medium taken inside along the carrying direction (sub-scanning direction). A discharge roller 20 for discharging the incoming print medium P is provided. The printer 100 also includes a carriage 10 that reciprocates in the main scanning direction (a direction orthogonal to the conveyance direction), a carriage motor 209 that moves the carriage 10, and various rollers 14 and 19. Is also provided with a print media conveyance control mechanism 207 for driving the printer. The printer 100 further includes a PW (Paper Width) sensor 213, a memory (for example, a nonvolatile memory such as an EEPROM) 231, a user interface (UI) 101, and a print controller 211.

  The PW sensor 213 is a print media sensor provided on the surface of the print head 13 that faces the print media P (specifically, for example, used to detect the width of the print media P). The PW sensor 213 is, for example, an optical sensor having a light emitting element and a light receiving element, and whether or not a print medium exists below the sensor is determined by the incident light (for example, reflected light) from the light emitting element to the light receiving element. The print controller 211 determines based on whether the intensity has changed.

  The UI 101 is a device for a human to make a desired input to the printer 100, and is, for example, an operation button or a touch panel.

  The print controller 211 is a computer program (or hardware or a combination thereof) for controlling various operations for printing, and functions by being read into a CPU from a predetermined storage medium (for example, ROM). . The print controller 211 controls the driving of the carriage motor 209, thereby controlling the travel of the carriage 10, and controlling the print media conveyance control mechanism (for example, various motors) 207, thereby supplying the supply roller 14 and the conveyance roller 14. The rotation of the roller 19 and the discharge roller 20 is controlled. The print controller 211 also performs processing for writing information based on the detection result of the PW sensor 213 into the memory 231 (details will be described later).

  FIG. 2A shows the surface of the print head 13 that faces the print medium P.

  On the surface of the print head 13 facing the print medium P, a plurality of nozzle rows 24, 24,... Are arranged along the main operation direction. Each nozzle row 24 corresponds to, for example, a predetermined ink color, and is a long row along the transport direction. Each nozzle row 24 is constituted by a plurality of nozzles 25 arranged at a predetermined interval (for example, 1/180 inch). From each nozzle 25 of each nozzle row 24, ink droplets of a color corresponding to the nozzle row 24 are ejected. The reference nozzle 25B is included in at least one nozzle row 24 (the nozzle used as the reference nozzle 25B may be the nozzle 25 existing at any nozzle position). The position of the reference nozzle 25B in the transport direction is a position serving as a reference for a plurality of nozzle positions in the transport direction.

  A PW sensor 213 is mounted on the surface of the print head 13 that faces the print medium P. The PW sensor 213 is mounted at a position away from the most upstream nozzle position in the transport direction (hereinafter, the rearmost nozzle position) by a predetermined distance G of the transport direction component.

  In the first embodiment, the print medium P is cued, for example, the print medium is transported so that the front end of the print medium P overlaps with the cue position (in other words, the transport start position). The extraction is performed based on the detection result of the PW sensor 213. Specifically, for example, the print controller 211 controls the transport amount of the print medium P after the print medium P is detected by the PW sensor 213 (for example, the drive amount of each motor in the print media transport control mechanism 207). Thus, the cueing of the print medium can be controlled.

  However, the PW sensor 213 is not necessarily mounted at an accurate position, and an error may occur in the mounting position. Specifically, for example, as shown in FIG. 2A, the PW sensor 213 may be mounted at a position slightly longer than the predetermined distance G. In this case, the print media P cannot be accurately cued based on the detection result of the PW sensor 213.

  Therefore, in the first embodiment, the transport amount at the time of cueing of the print medium P is corrected based on the error of the mounting position of the PW sensor 213 by the device described in detail below. Hereinafter, the device will be described.

  FIG. 2B shows an example of a correction pattern printed on the print medium P.

  The print controller 211 can print the correction pattern as illustrated in FIG. 2B on the print medium P by giving print data for printing the correction pattern to the print head 13 and controlling the carriage motor 209. . The correction pattern is a pattern that is printed to specify how much the carry amount should be increased or decreased based on the error in the mounting position of the PW sensor 213. For example, the correction pattern is obtained from a plurality of marks 51A to 51G. Pattern. The plurality of marks 51 </ b> A to 51 </ b> G are printed at a plurality of positions different in the transport direction and the main operation direction (positions in the main operation direction may be the same). Each of the marks 51A to 51G is, for example, a line that is long in the main scanning direction. By printing at different positions in the main operation direction, it is easy to specify each mark, and information for specifying the mark in the vicinity of each mark (for example, at least one of upper, lower, left, and right) (for example, described later) IDs such as “+1”) can be printed.

  Of the plurality of marks 51A to 51G, the mark 51D is a mark formed by an ink droplet ejected from the reference nozzle 25B.

  A mark 51C existing next to the downstream side in the transport direction of the mark 51D is a mark formed by a nozzle (hereinafter referred to as a first downstream nozzle) 25 adjacent to the downstream side in the transport direction of the reference nozzle 25B. Therefore, the distance of the conveyance direction component between the mark 51D and the mark 51C is the same as the distance between the reference nozzle 25B and the first downstream nozzle 25 adjacent to the reference nozzle 25B. Hereinafter, similarly, the mark 51B is a mark formed by a nozzle (hereinafter referred to as a second downstream nozzle) 25 that is adjacent to the downstream side in the transport direction of the first downstream nozzle 25, and the mark 51A is This mark is formed by a nozzle (hereinafter referred to as a third downstream nozzle) 25 that exists adjacent to the downstream side of the second downstream nozzle 25 in the transport direction.

  On the other hand, the mark 51E that exists next to the upstream side in the transport direction of the mark 51D is a mark formed by the nozzle (hereinafter referred to as the first upstream nozzle) 25 that is adjacent to the upstream side in the transport direction of the reference nozzle 25B. . Accordingly, the distance in the conveyance direction component between the mark 51D and the mark 51E is the same as the distance between the reference nozzle 25B and the first upstream nozzle 25 adjacent to the reference nozzle 25B. Hereinafter, similarly, the mark 51F is a mark formed by a nozzle (hereinafter referred to as a second upstream nozzle) 25 that exists next to the upstream side in the transport direction of the first upstream nozzle 25, and the mark 51G is This mark is formed by a nozzle (hereinafter referred to as a third upstream nozzle) 25 that exists adjacent to the second upstream nozzle 25 on the upstream side in the transport direction.

  FIG. 2B shows “0”, “−1”, “+1” in order to make it easy to see how far the marks 51A to 51G are formed by the nozzles that are apart from the reference nozzle 25B. A combination of symbols and numbers such as. In the combination, the symbol “−” means that the nozzle is formed downstream of the reference nozzle 25B in the transport direction, and the symbol “+” exists upstream of the reference nozzle 25B in the transport direction. This means that the nozzle is formed by the nozzle, and the number means how far the nozzle is formed from the reference nozzle 25B (for example, “3” is formed by the third nozzle from the reference nozzle 25B). Means that). However, this combination is given to help the understanding of the description of the first embodiment, and actually it may not be printed (of course, it may be printed).

  In the first embodiment, a mark corresponding to a predetermined position from among a plurality of marks printed on the print medium P, specifically, for example, a predetermined distance (for example, from the front end of the print medium P along the transport direction). It is necessary to specify a mark (hereinafter referred to as a reference-corresponding mark) at or near the cueing position that is 3 mm away. This may be specified, for example, by human eyes, using a ruler or the like, or the print controller 211 may be a data source device (for example, an external memory or an image scanner). ) May be performed by analyzing the input image (read image of the print medium P on which the correction pattern is printed). However, the reference correspondence mark can be easily specified by using, for example, the mount-attached transparent sheet 30 illustrated in FIG. 3A as an auxiliary device for performing the specification.

  FIG. 3A shows an example of the transparent sheet 30 with mount.

  The transparent sheet 30 with mount is composed of a mount 32 and a transparent sheet 31, and the transparent sheet 31 opens and closes with the upper edge of the sheet 30 as an axis. As shown in FIG. 3A, a print medium P on which a correction pattern is printed can be sandwiched between the transparent sheet 31 and the mount 32.

  On the transparent sheet 31, a reference line 34 that is parallel to the main operation direction is written at the same position as the above-described cueing position (a position that is a predetermined distance away from the upper end of the transparent sheet 31 in the transport direction). . That is, the position where the reference line 34 is written is such that a predetermined position (for example, the upper end) of the transparent sheet 31 and a predetermined position (for example, the upper end) of the print medium P on which the correction pattern is printed overlap. When the print medium P is overlaid, the mark 51D (that is, the reference nozzle 25B) when the correction pattern is printed with no error in the mounting position of the PW sensor 213 and the print medium P is not inclined at all. The mark matches the mark printed in That is, when the correction pattern is printed in a state where there is no error in the mounting position of the PW sensor 213 and the print medium P is not tilted at all, as shown in FIG. When the print media P printed with is overlaid, the mark 51D overlaps the reference line.

  However, if there is an error in the mounting position of the PW sensor 213, for example, as shown in FIG. 3C, the mark 51D is located away from the reference line 34 and overlaps or is in close proximity to the reference line 34. The mark (that is, the reference correspondence mark) is different from the mark 51D (for example, the mark 51C).

  In the first embodiment, for example, correction value information including IDs (for example, numbers) of the respective marks 51A to 51G and correction values corresponding thereto are stored in the memory 231 (a computer for determining correction values). May be built into the program). The correction value corresponding to each of the marks 51A to 51G can be, for example, a carry amount corresponding to the distance between the reference nozzle 25B and each nozzle forming each of the marks 51A to 51G. Specifically, for example, the correction value corresponding to the mark 51C is a carry amount corresponding to the distance (for example, 1/180 inch) between the first downstream nozzle forming the mark 51C and the reference nozzle 25B. be able to.

  The print controller 211 specifies the correction value corresponding to the ID of the reference correspondence mark by referring to the correction value information in the memory 231, corrects the carry amount for cueing based on the correction value, and thereafter The cueing of the print medium can be executed with the corrected amount after the correction. Hereinafter, an example of the flow of processing performed in the printer 100 will be described.

  FIG. 4 shows an example of the flow of processing performed to determine the correction value.

  The print controller 211 controls the print media transport control mechanism 207 to transport the print media P (step S1). When the print medium P is detected by the PW sensor 213 by continuing to convey the print medium P (YES in S2), the print controller 211 determines the conveyance amount (for example, steps of various motors) after the detection is performed. By controlling (number), the print medium P is conveyed by a predetermined distance from the position detected by the PW sensor 213 and stopped (S3).

  Thereafter, the print controller 211 gives print data for printing the correction pattern to the print head 13 and controls the carriage motor 209 to print the correction pattern on the stopped print medium P. Thereby, the process of S4-S6 is performed. That is, for example, while the print head 13 travels once from one end side to the other end side, nozzles that exist downstream in the transport direction from the reference nozzle 25B (the third pattern in the example of the correction pattern in FIG. 2B). First, the mark 51A is printed using the downstream nozzles (S4), and then the nozzles to be used are switched one by one from the downstream side in the transport direction to the upstream side (NO in S5 and S6), and the rest The marks 51B to 51G can be printed. At the time of printing the correction pattern, at least the reference nozzle 25B is used.

  After the correction pattern is printed, that is, after all the marks 51A to 51G have been printed (YES in S5), the reference that overlaps or is closest to the predetermined cue position, that is, the reference that overlaps or is closest to the reference line 34 The correspondence mark is specified (S6). Specifically, for example, information indicating the reference correspondence mark (for example, from the upper end of the print medium P, from the person who specified the reference correspondence mark by sandwiching the print medium P printed with the correction pattern between the transparent sheets 30 with mount) The number indicating whether the mark is the second existing mark) is input via the UI 101, and the input information is stored in the memory 231. Alternatively, for example, the print controller 211 receives an input of a read image obtained by reading the transparent sheet 30 with the mount on which the print medium P on which the correction pattern is printed is sandwiched by the image scanner (for example, the image scanner). Alternatively, a reference correspondence mark that overlaps or is in the immediate vicinity of the reference line 34 can be identified by analyzing the read image received from an external memory). In S6, in the example of FIG. 3C, the mark 51C adjacent to the downstream side in the transport direction of the mark 51D is specified as the reference correspondence mark.

  The print controller 211 refers to the correction value information in the memory 231 to identify a correction value (for example, an offset value of the carry amount) corresponding to the identified reference correspondence mark ID, and uses the identified correction value. The data is written in the memory 231 (S8).

  FIG. 5 shows an example of a processing flow performed at the time of cueing.

  The print controller 211 controls the print media transport control mechanism 207 to transport the print media P (S11). When the print medium P is detected by the PW sensor 213 by continuing to convey the print medium P (YES in S12), the print controller 211 determines the conveyance amount (for example, various motor steps) after the detection is performed. (Number) is corrected with the correction value stored in the memory 231 (S13), and the print medium P is conveyed from the position detected by the PW sensor 213 and stopped by the corrected conveyance amount (S14).

  The above is the description of the first embodiment.

  In the first embodiment, for example, after the correction value is specified in S8 of FIG. 4, the print controller 211 uses the correction value to detect the transport amount for cueing (the print medium is detected by the PW sensor 213). The transport amount after the correction may be corrected and the corrected transport amount may be stored in the memory 231. In this case, the print controller 211 may cue the print medium with the corrected transport amount stored in the memory 231 when cueing the print medium.

  Further, for example, an auxiliary device for helping to specify the cueing correspondence mark is not limited to the transparent sheet 30 with mount. For example, the transparent sheet 31 itself may be an auxiliary device. In this case, for example, by positioning a predetermined position (for example, the upper left corner) of the transparent sheet 31 and a predetermined position (for example, the upper left corner) of the print medium P on which a plurality of marks are printed, Overlapping or nearest marks can be identified.

  According to the first embodiment described above, the correction value corresponding to the error in the mounting position of the PW sensor 213 is specified, and based on the correction value, the carry amount for cueing (in other words, by the PW sensor 213). The transport distance of the print medium from the position where the print medium is detected is corrected, and the print medium is cued with the corrected transport amount. Thereby, even if there is an error in the mounting position of the PW sensor 213, the print medium can be accurately cued.

  The second embodiment of the present invention will be described below. At that time, the difference from the first embodiment will be mainly described, and the description of the common points with the first embodiment will be omitted or simplified.

  For example, when the print medium is transported to a predetermined position in order to print the correction pattern, the print medium P may be inclined. In this case, the conveyance is stopped in a state where the print medium P is inclined, and therefore, the marks 51A to 51G in the correction pattern are printed while the print medium P is inclined with respect to the conveyance direction. For this reason, the printed marks 51 </ b> A to 51 </ b> G are inclined with respect to the print medium P. In this case, for example, in the example of FIG. 2C, when the correction pattern is printed without the print medium P being inclined, the reference corresponding mark that overlaps or is in the immediate vicinity of the reference line 34 becomes the mark 51C. However, when the correction pattern is printed in a state where the print medium P is tilted, a mark to be a reference corresponding mark is displaced, and a mark (for example, the mark 51D) different from the mark 51C corresponds to the reference corresponding mark. It will be a mark.

  Therefore, in the second embodiment, the degree of inclination of the print medium P is calculated by the device described in detail below, and the correction value corresponding to the specified reference correspondence mark is corrected based on the calculated degree of inclination. The carry amount for cueing can be corrected based on the corrected correction value.

  6 and 7 show an example of the flow of processing performed to correct the conveyance amount correction value. 8A and 8B are diagrams for helping understanding the processing flow. Specifically, FIG. 8A is a diagram for explaining a method of calculating the degree of inclination of the print medium P. FIG. 8B is a diagram for explaining a method for correcting the correction value based on the calculated degree of inclination. Hereinafter, with reference to these drawings, processing performed to correct the correction value of the carry amount will be described. In the following description, the word “media feed start position Y0” appears, which means the transport start position of the print medium 21. Specifically, for example, the print medium is stopped by a stopper (not shown). Or a position where the print medium is detected by another sensor (not shown) located upstream of the PW sensor 213 in the transport direction.

  The print controller 211 moves the print head 13 so that the position of the PW sensor 213 in the main scanning direction is a first position X1 (see FIG. 8A, in this description, the coordinate in the main scanning direction is X1) ( S21 in FIG. 6).

  Then, the print controller 211 performs the first transport required from the media feed start position Y0 (see FIG. 8A, in this description, the coordinate in the transport direction is zero) until the print medium P is detected by the PW sensor 213. Determine the quantity a. Specifically, for example, the print controller 211 counts the transport amount from the media feed start position Y0 (S22), and if the print medium P is detected by the PW sensor 213 (YES in S23), the detection is performed. The print medium P is transported by a predetermined transport amount y such that the print medium P is transported by a predetermined distance from the determined position and stopped (S24). The print controller 211 calculates the first transport amount a by subtracting the predetermined transport amount y from the total transport amount k1 from the count in S22 until the print medium P stops, and the calculated first transport amount a. Is stored in the memory 231 (S25). The transport distance based on the first transport amount a is defined as a first transport distance A illustrated in FIG. 8A.

  Next, the print controller 211 carries the carry amount −k1 for returning the print medium P by the carry distance corresponding to the entire carry amount k1, in other words, the carry amount for returning the print medium P to the media feed start position Y0. By giving -k1 to the print media conveyance control mechanism 207, the rollers 14, 19 and 20 are rotated in reverse to return the print media P (S26).

  Next, the print controller 211 moves the print head 13 so that the position of the PW sensor 213 in the main scanning direction is the second position X2 (see FIG. 8A, in this description, the coordinate in the main scanning direction is X2). Then, the process from S22 to S24 described above is executed (S27). Then, the print controller 211 calculates the second transport amount b by subtracting the predetermined transport amount y from the entire transport amount k2, and stores the calculated second transport amount b in the memory 231 (S28). A transport distance by the second transport amount b is a second transport distance B illustrated in FIG. 8A.

  Thereafter, the print controller 211 performs the same processing as S4 to S6 in FIG. 4 in a state where the print medium P is transported by the predetermined transport amount y and stopped at the second position X2 (S29 to S29 in FIG. 7). S31), the correction pattern is printed on the print medium P. After that (YES in S30), as in S7 of FIG. 4, the reference correspondence mark that overlaps or is in close proximity to the reference line 34 is specified (S32). For example, in the example of FIG. 3C, even if there is an error in the mounting position of the PW sensor 213, when the correction pattern is printed without the print medium P being inclined, the reference corresponding mark is the mark 31C. When the correction pattern is printed in a state where the medium P is tilted, the reference corresponding mark is not the mark 31C, but is a mark 51D as in the example of FIG. 8A, for example.

Therefore, the print controller 211 specifies a correction value corresponding to the reference corresponding mark (the mark 51D in the example of FIG. 8A) by referring to the correction value information in the memory 231, and calculates the inclination degree of the print medium P. Then, the specified correction value can be corrected based on the calculated inclination degree. Specifically, for example, the print controller 211 is based on the first transport amount a and the second transport amount b stored in the memory 231 and the first position X1 and the second position X2. The correction value corresponding to the reference corresponding mark can be corrected (S33), and the corrected correction value can be stored in the memory 231. Hereinafter, the right triangle shown in FIG. 8B will be described in more detail with reference to FIGS. 8A and 8B. The right triangle shown in FIG. 8A has three coordinates (X1, 0), (X1, AB) and (X2, It is a right triangle whose vertex is 0). X1 corresponds to the position in the main scanning direction of the rightmost mark 51G in the correction pattern, and X2 corresponds to the position in the main scanning direction of the leftmost mark 51A in the correction pattern. The positions X3 to X7 in the main scanning direction of the line segments L1 to L5 parallel to the base L6 of the right triangle correspond to the positions in the main scanning direction of the marks 51B to 51F. X2, X3 to X7, and X1 are equally spaced. Therefore, if L6 = A−B (the difference between the first transport distance A and the second transport distance B, in other words, the degree of inclination of the print medium P), L1 = (A−B) / 6, L2 = 2 (A−B) / 6, L3 = 3 (A−B) / 6, L4 = 4 (A−B) / 6, and L5 = 5 (A−B) / 6.

  Therefore, for example, as in the example of FIG. 8A, when the mark 51D is specified as the reference corresponding mark, the print controller 211 determines that the length 3 (A−B) / of the line segment L3 corresponding to the position of the mark 51D. 6, the correction value corresponding to the mark 51D can be corrected (for example, 3 (A−B) / 6 is added to the correction value). The print controller 211 can store the corrected correction value in the memory 231.

  Thereafter, in the cueing of the print medium, as described with reference to FIG. 5, the carry amount for cueing is corrected according to the corrected correction value stored in the memory 231. The print media is cued by the transport amount.

  In this second embodiment, a plurality of marks are printed at a plurality of positions different in the main scanning direction, and two transport amounts at two different positions in the main scanning direction (specifically, the printing medium P is printed from a predetermined position). The degree of inclination of the print medium is calculated from the difference in the amount of conveyance until the image is detected. Then, based on the degree of inclination and the position of the specified reference correspondence mark, the correction value corresponding to the specified reference correspondence mark is corrected. As a result, the correct correction value can be set even using the print medium P on which the inclined correction pattern is printed.

  The preferred embodiments of the present invention have been described above, but these are examples for explaining the present invention, and the scope of the present invention is not limited to these embodiments. The present invention can be implemented in various other forms.

  For example, the printer 100 optically detects a range including a plurality of marks (for example, marks corresponding to at least the specified position) from the front end of the print medium, and corresponds to the specified position based on the detection result. The mark to be specified can be specified. Specifically, for example, an image sensor such as a CCD (Charge Coupled Devices) may be provided in the carriage 10 or the print head 13 (the PW sensor 213 may be an image sensor). For example, the image sensor can detect an image in a range including a plurality of marks (for example, marks corresponding to at least the specified position) from the front end of the print medium. By analyzing the detected image, the print controller 211 can identify a mark that overlaps or is closest to the cueing position that is a predetermined distance away from the front end of the print medium along the transport direction.

FIG. 1 is a diagram for explaining a portion related to conveyance of a print medium in the printer according to the first embodiment of the present invention. FIG. 2A shows the surface of the print head 13 that faces the print medium P. FIG. 2B shows an example of a correction pattern printed on the print medium P. FIG. 3A shows an example of the transparent sheet 30 with mount. FIG. 3B shows that when the correction pattern is printed in a state where there is no error in the mounting position of the PW sensor 213 and the print medium P is not inclined at all, the print medium P on which the correction pattern is printed is below the transparent sheet 31. The state when superimposed on is shown. FIG. 3C shows an example of a state in which the print medium P on which the correction pattern is printed is overlaid under the transparent sheet 31 when the correction pattern is printed with an error in the mounting position of the PW sensor 213. Show. FIG. 4 shows an example of the flow of processing performed to determine the correction value. FIG. 5 shows an example of a processing flow performed at the time of cueing. FIG. 6 shows a part of an example of the flow of processing performed to determine a correction value in the second embodiment of the present invention. FIG. 7 shows the remaining part of an example of the flow of processing performed to determine the correction value in the second embodiment of the present invention. FIG. 8A is a diagram for explaining a method of calculating the degree of inclination of the print medium P in the second embodiment of the present invention. FIG. 8B is a diagram for explaining a method for correcting the correction value based on the calculated inclination degree.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Carriage 13 ... Print head 14 ... Supply roller 19 ... Conveyance roller 20 ... Discharge roller 100 ... Printer 101 ... UI (user interface) 207 ... Print media conveyance control mechanism 209 ... Carriage motor 211 ... Print controller 213 ... PW Sensor 231 ... Memory

Claims (8)

Conveying means for conveying the print media;
A print media sensor for detecting the conveyed print media;
Transport control means for controlling the transport means so as to transport the print media from a front end of the print media detected by the print media sensor to a predetermined position;
Mark printing means for printing a plurality of marks at positions on the print medium that are different in the transport direction of the print medium including the prescribed position;
Mark identifying means for identifying a mark corresponding to the cue position from the tip;
Storage means for storing a correction value corresponding to the specified mark,
By correcting the transport amount from the front end with the stored correction value, and transporting the print medium with the transport amount after the correction, the print medium is transported to the heading position.
Printer. Further comprising a print head having a plurality of dot forming elements along the transport direction;
The mark printing unit prints the plurality of marks on the print medium while moving the print head in a main scanning direction orthogonal to the transport direction and changing a dot forming element used in each of the plurality of marks. ,
The plurality of marks are respectively printed at different positions in the main scanning direction, and the print medium is not conveyed at the time of printing.
The printer according to claim 1. The correction value stored in the storage means is obtained based on the calculated degree of inclination and the position of the specified mark.
The printer according to claim 1 or 2. The correction value stored in the storage means is obtained based on the calculated degree of inclination and the position in the transport direction and the position in the main scanning direction of the specified mark.
The printer according to claim 2. A media transport amount calculating means for calculating the transport amount of the print media;
The media transport amount calculation means obtains respective distances from the predetermined reference line set to the downstream side in the transport direction and in the main scanning direction to two points along the tip detected by the print media sensor, The degree of inclination is calculated based on the distance.
The printer according to claim 2 or 4. The mark specified by the mark specifying means is a mark input in a state where a transparent sheet on which a reference mark is printed at the specified position is overlaid on a print medium on which the plurality of marks are printed. ,
The printer as described in any one of Claims 1-5. The mark specified by the mark specifying means is a mark specified by detecting positions of the plurality of marks with the print media sensor.
The printer as described in any one of Claims 1-5. Transporting the print media by a transport means;
Detecting the conveyed print media;
Controlling the transport means to transport the print media from the detected leading edge of the print media to a specified position;
Printing a plurality of marks at positions on the print medium that are different in the transport direction of the print medium including the prescribed position;
Identifying a mark corresponding to the cue position from the tip;
Storing a correction value corresponding to the specified mark in a storage means;
A step of correcting the transport amount from the leading edge with the stored correction value and transporting the print medium to the heading position by transporting the print medium with the transport amount after the correction. How to cue media.

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