JP2012223946A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time from the replacement of a paper sheet to a state of being ready to be printed.SOLUTION: An image forming apparatus that performs printing by a printing means having elongated recording paper in a carriage includes: a forming means for the recording paper; a user interface means through which paper sheet information setting can be performed; and a control means for concurrently operating the forming means and a means for prompting an input to the user interface means.

Description

  The present invention relates to an image forming apparatus.

  An ink jet recording apparatus is an image forming apparatus that prints by ejecting ink onto recording paper. Printing is performed by ejecting ink from an ink head provided in a carriage that moves in the width direction of the recording sheet perpendicular to the conveying direction while conveying the recording sheet.

  Some ink jet recording apparatuses use roll paper as recording paper. When the roll paper is exchanged, forming is performed for setting paper information and preparing for conveyance of the recording paper. Specifically, the sensor provided in the carriage scans the printable range of the recording paper, skew detection for detecting that the recording paper is being transported obliquely, or the return conveyance of the paper for correcting the skew. It is conveyance.

  This forming is usually performed by moving the carriage in the width direction of the recording sheet while the recording sheet is fixed to the conveyance path by suction. At this time, it is necessary to prevent the recording paper from floating from the conveyance path and causing the ink head of the carriage and the recording paper to come into contact with each other to physically damage the ink head. For this reason, it is necessary to reliably attract the recording sheet to the conveyance path surface.

  Usually, the recording paper is adsorbed on the conveyance path surface by a suction device. This suction device is provided with a large number of minute holes on the conveyance path surface side, and sucks air through the minute holes by a suction fan or the like. The transported recording paper is sucked to the surface of the transport path surface by the suction device. However, if the recording paper is strongly attracted to the transport path surface, the recording paper may not be transported smoothly and a paper jam may occur. Therefore, the suction device needs to suck with a suction force suitable for the recording paper.

  Conventionally, in an ink jet recording apparatus using roll paper, information such as paper size, paper type or paper thickness necessary for a user to obtain an appropriate suction force is set in advance, and forming is started after the setting. For this reason, the time from the start of the roll paper replacement to the printable state is the total time of the operation time for setting the paper information and the forming operation time that starts thereafter, and it may take a long time in some cases.

  As a method for reducing the operation time for setting paper information, Patent Document 1 discloses a paper type detection unit that detects a paper type including a paper thickness. Patent Document 2 discloses a detection device that detects the width of a sheet.

  Patent Document 1 discloses a paper storage unit that holds sheets in a stack, a separation sheet feeding unit that separates sheets one by one, and a sheet by feeding a predetermined amount of a sheet leading edge at a timing prior to a sheet feeding command. An image forming apparatus that detects a paper type by a seed detection unit is disclosed. Although the paper information setting means can reduce the paper information setting time, it does not target long paper such as roll paper. Further, there is no mention of forming that takes a long time from the start of roll paper replacement until it becomes ready for printing.

  Patent Document 2 controls a suction force of a suction device that sucks and supports a sheet on a platen on which the sheet is placed, feeds the sheet onto the platen, supports the carriage that scans in the sheet width direction. An image forming apparatus that scans and detects the width of a sheet by a detection device is disclosed. However, the forming operation time is not taken into consideration. Further, since an apparatus for detecting the paper type and paper thickness is not disclosed, an appropriate suction force based on the paper size, paper type, and paper thickness cannot be obtained.

  It is an object of the present invention to provide an image forming apparatus capable of shortening the time from paper replacement to printable state.

  In view of the above problems, the present invention provides an image forming unit that conveys a long recording sheet and prints on the recording sheet by a printing unit provided in a carriage that moves in the width direction of the recording sheet. Forming means including means for detecting skew of the recording paper and means for correcting skew until the recording paper is set in a printable state after the recording paper is set for paper replacement, and the recording An image forming apparatus comprising: user interface means capable of setting paper information and the like of paper; and control means for simultaneously performing the operation of the forming means and the operation of a confirmation means for prompting input to the user interface means It is.

According to the present invention, there is an effect that it is possible to shorten the time from the replacement of a long sheet to the printable state.

1 is a diagram illustrating a schematic configuration of an ink jet recording apparatus according to an embodiment of the present invention. It is a figure which shows an example of the layout of the inkjet recording device of one Embodiment of this invention. FIG. 4A is a front view of the image forming apparatus, and FIG. 4B is a plan view of the main part. It is a figure explaining 2 steps | paragraphs of conveyance in operation | movement of the means to detect skew. It is a figure which shows the process sequence at the time of sheet replacement. FIG. 6 is a diagram illustrating an example of a screen that prompts input of paper information. It is a figure which shows an example of the process sequence from skew detection to skew correction. FIG. 10 is a plan view illustrating an example of an operation of detecting a skew when sheet information is not fixed. FIG. 10 is a plan view illustrating an example of an operation of detecting a skew when paper information is confirmed. It is a figure which shows an example of the process sequence until it will be in a printable state.

  The image forming apparatus according to the present invention will be described in detail with reference to FIGS. 1 to 9 as an embodiment in which an ink jet recording apparatus is used as an image forming unit. The present invention uses a carriage other than the ink jet recording apparatus as the image forming means, for example, a means for printing by irradiating a light source such as a laser to fix toner, a means for printing on a thermal paper or the like by a thermal method, etc. The present invention can be applied to any means as long as it performs image formation.

  FIG. 1 is an example of a configuration diagram of an embodiment of the present invention.

  In FIG. 1, the image forming apparatus 1 includes an image forming unit 2, a conveying device 3, a suction device 4, a print information setting unit 5, a forming unit 6, and a control unit 7.

  The image forming unit 2 is a unit that forms an image on a recording medium. The image forming unit 2 includes a carriage 21. The carriage 21 moves on the recording medium, and an image is formed by ejecting ink from the ink head by the image forming means provided in the carriage 21, in this embodiment, the ink jet recording apparatus. The position of the carriage 21 is detected by an encoder (not shown) provided on the path along which the carriage 21 moves. For example, belts having a plurality of slits are arranged in parallel on the path along which the carriage 21 moves, the number of slits is read by a sensor while the carriage 21 is moving, and the position is calculated from the number of slits. The method for detecting the position of the carriage 21 may be configured other than the encoder.

  The conveyance device 3 is a device that conveys a recording medium on which an image is formed. Some are constituted by a roller or a conveyor belt. The conveyance device 3 has a conveyance path for conveying the recording medium. In this embodiment, in the case of a roller to be described later, the recording medium in contact with the roller is conveyed by the rotation of the roller installed in the conveyance path.

  The suction device 4 is a device that sucks and fixes the recording medium when the image forming unit 2 forms an image. In this embodiment, air is sucked from a plurality of minute suction ports, which will be described later, and a recording medium near the suction ports is sucked and fixed.

  The print information setting means 5 is a means for setting or confirming paper information. The print information setting unit 5 includes a user interface unit 51 that can set paper information and the like, a confirmation unit 52 that prompts input to the user interface unit 51, or other unit that inputs, outputs, or confirms information necessary for image formation. ing. As the confirmation means 52, in addition to the screen display means 53, other means such as voice can be recognized that the user needs to input.

  The forming means 6 is a means for making preparations so that image formation can be started after the roll paper or the like is set when a long recording medium such as roll paper is replaced. Forming by the forming means 6 includes skew detection for detecting a state in which the recording medium is not transported correctly (hereinafter referred to as skew), such as a recording medium being transported in an inclined state (an oblique state), and a case where the skew is detected. And skew correction for correcting the conveyance state of the recording medium so that the recording medium is conveyed in a correct state. The forming means 6 includes means 61 for detecting skew and means 62 for correcting skew.

  The control means 7 is a means for instructing each component of the image forming apparatus 1 and controlling its operation and action. For example, there is one constituted by a PC or a microcomputer. The PC or the like includes a CPU, a ROM, and a RAM. Note that some functions of the control means 7 may be connected to a network.

  The recording medium is a long medium that is rolled or folded, and an image is formed on the medium. As the type of medium, it is possible to use plain paper, high-quality paper, OHP sheet, synthetic resin film, metal thin film, etc. In this embodiment, a roll paper-like recording paper 38 is used as a long medium.

  Next, each component of the image forming apparatus will be described with reference to FIG.

  The image forming unit 2 includes a carriage 21, a carriage sensor 22, and an ink head 23.

  The carriage 21 is a device that moves above the recording paper 38 and moves in a direction perpendicular to the transport direction (hereinafter referred to as the paper width direction) while the recording paper 38 and the ink head 23 maintain a constant distance. At the time of image formation, the carriage 21 moves and ink is ejected from the ink head 23 provided on the carriage 21 to a predetermined position on the recording paper 38 to form an image.

  The carriage 21 normally stands by at a carriage standby position 24 outside the width of the recording paper 38 except during image formation. At the carriage standby position 24, during the standby, the ink head 23 is not dried, the ink head 23 is prevented from being soiled or clogged, and processing is performed so that ink is immediately ejected during the next image formation. Is called.

  The carriage sensor 22 is a detection device that detects the presence or absence of the recording paper 38. The carriage sensor 22 is mounted on the carriage 21 and moves as the carriage 21 moves.

  The transport device 3 includes a paper feed tray 30, a paper feed roller 31, a registration roller 32, a paper feed sensor 33, a registration sensor 34, and a transport path 35. The paper feed roller 31 and the registration roller 32 move the recording paper 38 in contact with the rollers by the rotation of the rollers. The paper feed roller 31 is a roller for the user to grip the leading end of the recording paper 38 when the roll paper 39 is replaced.

  The paper feed sensor 33 and the registration sensor 34 are detection devices that detect the presence or absence of the recording paper 38. The paper feed sensor 33 detects the recording paper 38 when the paper feeding roller 31 holds the leading end of the recording paper 38. The registration sensor 34 is a detection device that detects the presence or absence of the recording paper 38 at the registration standby position 36.

  The leading end of the recording paper 38 is disposed at a registration standby position 36 that is a distance p away from the registration sensor 34 immediately before starting image formation. At the start of image formation, the recording paper 38 is conveyed from the registration standby position 36. The amount of movement of the leading edge of the recording paper 38 is calculated from the rotational speeds of the paper feed roller 31 and the registration roller 32 with reference to the position of the registration sensor 34.

  The suction device 4 includes a paper placement unit 41 and a suction port 42. The paper placement unit 41 sucks and fixes the recording paper 38 transported to the transport path 35 to the surface thereof. The suction port 42 is a plurality of minute holes provided in the paper placement unit 41.

  In this embodiment, air is sucked from the suction port 42 of the paper placement unit 41 with a negative pressure generated by the rotation of a suction fan (not shown), and the recording paper 38 on the paper placement unit 41 is sucked and fixed.

  The cutter 93 installed on the downstream side of the conveyance path 35 is an apparatus that cuts the recording paper 38 after printing is completed and produces one page of printed paper. A paper discharge roller 91 installed further downstream of the transport path 35 is a device for discharging printed paper in the paper transport direction. A paper discharge sensor 92 installed downstream of the paper discharge roller 91 detects the trailing edge of the cut printed paper, and the image forming apparatus 1 determines that the paper discharge is complete.

  Next, the operation of the image forming apparatus 1 during image formation will be described.

  The image forming apparatus 1 obtains a suction force suitable for the recording paper 38 from the paper information set by the print information setting unit 5. The suction device 4 is set to a suitable suction force. Thereafter, the leading end portion of the recording paper 38 is conveyed from the registration standby position 36 to the paper arrangement portion 41 of the suction device 4 by the registration rollers 32 of the conveyance device 3. Further, thereafter, the carriage 21 moves on the recording paper 38 in the paper width direction.

  Since the suction device 4 is set to a suction force suitable for the recording paper 38, the recording paper 38 can be transported without the recording paper 38 floating even during the operation of the image forming means 2.

  The image forming unit 2 ejects ink to a predetermined position on the recording paper 38 by the ink head 32 provided on the carriage 21 while the carriage 21 moves on the recording paper 38. After the completion of ejection, the registration roller 32 and the like convey the next image forming position of the recording paper 38 to the paper placement unit 41. Thereafter, the image forming unit 2 repeats ink ejection to form an image for one page.

  After the image for one page is formed, the registration roller 32 and the like convey the printed recording paper 38 in the paper conveyance direction. A cutter 93 installed downstream of the conveyance path 35 cuts the printed recording paper 38 for one page and creates a printed paper for one page. After cutting, the paper discharge roller 91 discharges the printed paper in the paper transport direction.

  The control means 7 determines that the paper discharge has been completed when the paper discharge sensor 92 detects the trailing edge of the cut printed paper.

  Thereafter, the registration rollers 32 and the like are driven in the reverse direction, and the leading end portion of the cut recording paper 38 is returned to the registration standby position 36 and conveyed. When the leading edge of the recording paper 38 is returned to the registration standby position 36, the image for the next page can be formed.

  Next, the forming means 6 for preparing to be ready for image formation after replacing the roll paper 39 will be described. Forming by the forming means 6 includes skew detection and skew correction.

  The skew detection is performed by the carriage 21 having the carriage sensor 22 moving on the recording paper 38 (hereinafter, the operation in which the carriage 21 moves in the width direction of the recording paper 38 when the skew is detected is referred to as “scanning operation”). . During this scanning operation, no ink is ejected from the ink head 23 provided in the carriage 21.

  The forming means 6 includes means 61 for detecting skew and means 62 for correcting skew.

  The skew detecting means 61 first transports the recording paper 38 by the transport amount n, and then transports the recording paper 38 by the transport amount m in two stages, and the end position of the recording paper 38 at the first stage transport. And the end position of the recording paper 38 at the time of the second stage conveyance, and it is determined whether or not the skew is generated based on whether or not the difference is within a predetermined error range.

  Hereinafter, the skew detection by the means 61 for detecting the skew will be specifically described with reference to FIG.

  After the sheet replacement, the leading end of the recording sheet 38 is disposed at the resist standby position 36.

  First, as a first step, the registration rollers 32 and the like convey the leading end portion of the recording paper 38 to a position away from the registration sensor 34 by a distance n (hereinafter, the conveyance amount at this time is referred to as a first conveyance amount n). FIG. 3A shows the position of the recording paper 38 at the position of the first transport amount n. The carriage sensor 22 mounted on the carriage 21 performs a scanning operation at the position of the first transport amount n to detect the end position a1 of the recording paper 38, and the carriage 21 from the carriage standby position 24 to the detection position is detected. The moving distance is measured by an encoder provided on the path along which the carriage 21 moves, and is set as the position of the recording paper 38 (FIG. 3 (2)).

  Next, as the second stage of conveyance, the leading edge of the recording paper 38 is conveyed to a position further away from the position of the first conveyance amount n by the registration roller 32 or the like (hereinafter referred to as a second conveyance amount m). ). FIG. 3 (3) shows the position of the recording paper 38 at the position of the second transport amount m. At the position of the second transport amount m, the position a2 of the recording paper 38, which is the distance from the carriage standby position 24, is measured in the same manner as described above (FIG. 3 (4)).

  The difference between the end position a1 of the recording paper 38 at the position of the first transport amount n and the end position a2 of the recording paper 38 at the position of the second transport amount m is obtained, and the difference is within a predetermined error range. In this case, it is determined that there is no skew, and when it is out of the predetermined error range, it is determined that skew is occurring.

  Next, the means 62 for correcting the skew will be described. The skew correcting unit 62 corrects the skew by returning and transporting the recording paper 38 so that the recording paper 38 is transported in a correct state when the skew is detected. .

  Specifically, when it is determined that the skew has occurred, the registration roller 32 or the like again transports the leading end portion of the recording paper 38 back to the position of the first transport amount n. Thereafter, the skew detection shown in FIGS. 3 (1) to 3 (4) is repeated by means 61 for detecting the skew described above. As a result of the skew detection, when it is determined that the skew is generated, the sheet is further returned and conveyed, the skew detection is repeated, and the skew detection is repeated a predetermined number of times until it is determined that the skew is not generated.

  If it is determined that a skew has occurred even after repeating a predetermined number of times, the user again sets the roll paper 39 in the paper feed tray 30 as a paper error (hereinafter referred to as a roll forming error). Encourage you to.

  When the forming means 6 determines that no skew has occurred, or when it is determined that no skew has occurred due to skew detection within a predetermined number of times, the leading end of the recording paper 38 is placed at the resist standby position 36. Carry back. At this time, the image forming unit 2 is ready to form an image.

  As described above, the forming process after the roll paper 39 is replaced is completed.

  In the image forming apparatus 1 described above, a procedure (processing flow) from the replacement of the recording paper 38 to a state where image formation is possible (printable state) will be described.

  FIG. 4 shows the processing procedure of the control means 7 from the start of the operation of the forming means 6 until the skew is detected after the user sets the roll paper 39 by paper exchange or the like (from step 401). 417).

The control means 7 stops the suction of the suction device 4 when the paper is replaced (step 401).
After setting the roll paper 39 on the predetermined paper feed tray 30, the user pulls out the leading end of the roll paper 39 and sets it so that the leading end is held by the paper feeding roller 31 (step 402). At this time, the paper feed sensor 33 disposed in front of the paper feed roller 31 detects the roll paper 39, and the control means 7 determines that the recording paper 38 is set (in the case of “Yes” in step 403).

  In order to start the operation of the forming means 6, the control means 7 conveys the leading end of the recording paper 38 to the registration standby position 36 by the registration roller 32 or the like (step 404) and at the same time, confirms the input to the user interface means 51. The means 52 is activated (process A in the figure). The operation of the confirmation means 52 that prompts input (processing A in the figure) will be described later.

  When the registration sensor 34 detects the recording paper 38 (“Yes” in step 405), the control means 7 turns the suction device 4 “ON” with “Duty minimum” (actuates the suction force with the minimum). (Step 406). Thereafter, the registration rollers 32 and the like convey the leading end portion of the recording paper 38 to the position of the first conveyance amount n. Since the suction device 4 has the minimum suction force, the recording paper 38 can be transported on the transport path 35 by the rotation of the registration roller 32 and the like while maintaining the state in contact with the transport path 35 (step 407).

  The control means 7 calculates the amount of conveyance from the registration sensor 34 at the leading end of the recording paper 38 from the number of rotations of the registration rollers 32 and the like, and sets it as the movement amount of the recording paper 38 (step 407). Further, it is determined whether or not the moving amount of the recording paper 38 has reached the first transport amount n (step 408).

  When the movement amount is less than the first conveyance amount n, the rotation of the registration roller 32 is continued. When the amount of movement becomes equal to or greater than the first transport amount n (“Yes” in step 408), the rotation of the registration roller 32 and the like is stopped, and the transport of the recording paper 38 is stopped. At the same time, the suction device 4 is switched to “Duty maximum” (the suction force is operated at the maximum) (step 409).

  Since the suction force of the suction device 4 is maximum, the recording paper 38 is securely fixed to the transport path 35 without being lifted. Therefore, the carriage 21 can be scanned on the recording paper 38 even if paper information is not set.

  Thereafter, the control means 7 clears the variable count for storing the number of skew corrections to 0 (step 410).

  Next, processing A in FIG. 4 will be described.

The control means 7 performs the operation of the confirmation means 52 that prompts input of paper information simultaneously with the operation of the forming means 6 (step 404) (step 411). FIG. 5A shows an example of a screen display means 53 for a screen that prompts input of paper information as the confirmation means 52 of the print information setting means 5.
The control means 7 displays a screen prompting input by the screen display means 53 (step 411 in FIG. 4), and then sets the variable Info as “unconfirmed” as an initial value of a flag indicating that the setting of the paper information is not confirmed Save (step 412 in FIG. 4).

  When the user presses the “setting” key 54 in FIG. 5A and completes the paper size setting, paper type setting, and paper thickness setting, the control means 7 confirms the variable Info and the paper information setting. Is saved as a flag “confirmed” (steps 413 to 416 in FIG. 4). In the subsequent processing, the control means 7 can confirm the variable Info and determine whether or not the setting of the paper information is confirmed.

  After the paper information flag becomes “confirmed”, the screen prompting input of paper information in FIG. 5A is deleted (step 417 and FIG. 5B).

  On the other hand, the control means 7 continues to display a screen for prompting input until the setting of the paper information is confirmed. Therefore, the user can make settings necessary for the copy operation and printing start. As will be described later, the image forming apparatus 1 does not enter a state in which an image can be formed until the setting of the paper information is confirmed.

  As described above, after the roll paper 39 is replaced, the processing procedure from when the operation of the forming means 6 is started until skew detection is completed (“B” and “END” in FIG. 4).

  Next, a specific operation procedure of skew detection and skew correction of the operation of the forming means 6 will be described with reference to FIG. 7 and 8 are plan views of the operation of the carriage 21 and the transport operation of the recording paper 38 during the scanning operation as viewed from above. The positions of the carriage 21 and the recording paper 38 at the respective steps in FIG. It is shown.

  In FIG. 6, the control means 7 transports the leading end of the recording paper 38 to the position of the first transport amount n by the registration roller 32 or the like in order to detect skew. Thereafter, the carriage 21 at the carriage standby position 24 is stopped on the left side of the recording paper 38 (position where the carriage sensor 22 detects “paper present”) (step 501, FIG. 7 (1) and FIG. 8 (1)).

  The control means 7 measures the distance traveled from the carriage standby position 24 to the stop position where the carriage 21 is stopped by an encoder provided on the path along which the carriage 21 moves, and stores it as a variable a1 (step 501, FIG. 7 ( 1) and FIG. 8 (1)).

  At this time, the control means 7 determines whether or not the paper information has been determined by the paper information flag (variable Info) (step 519).

  If the paper information flag is “indeterminate” (“Yes” in step 519), the suction force of the suction device 4 is switched to the maximum. Thereafter, the carriage 21 is stopped at the right end surface of the recording paper 38 (position where the carriage sensor 22 detects “no paper”) (step 502, FIG. 7 (2)). At this time, the control means 7 measures the distance from the carriage standby position 24 to the stop position where the carriage 21 is stopped by an encoder provided on the path along which the carriage 21 moves, and stores it as a variable b1 (step 502, FIG. 7). (2)).

  The control means 7 can detect the paper width of the recording paper 38 from the variables a1 and b1.

  Next, after returning the carriage 21 to the carriage standby position 24, the control means 7 switches the suction force of the suction device 4 to the minimum (step 503, FIG. 7 (3)). Thereafter, as the second stage of conveyance, the leading end of the recording paper 38 is conveyed to the position of the second conveyance amount m (step 504).

  The control means 7 calculates the amount of movement of the leading edge of the recording paper 38 (step 505) and determines whether the leading edge of the recording paper 38 has reached the position of the second transport amount m (step 506). At this time, if the movement amount is less than the second conveyance amount m, the conveyance is continued, and when the movement amount exceeds the second conveyance amount m (“Yes” in step 506), the rotation of the registration roller 32 and the like is stopped. Then, the conveyance of the recording paper 38 is stopped (step 507, FIG. 7 (4)).

  At the same time, the control means 7 switches the suction force of the suction device 4 to the maximum (step 507). By switching the suction force to the maximum, the recording paper 38 is securely fixed to the paper placement unit 41 without being lifted.

  In this state, the carriage 21 at the carriage standby position 24 is moved to the left end surface position of the recording paper 38 and stopped. At this time, the control means 7 measures the distance from the carriage standby position 24 to the stop position where the carriage is stopped by an encoder provided on the path along which the carriage 21 moves, and stores it as a variable a2 (step 508, FIG. 7 ( 5)).

Thereafter, the carriage 21 is returned to the carriage standby position 24, and the suction force of the suction device 4 is switched to the minimum. (Step 509, FIG. 7 (6))
On the other hand, when the paper information flag (variable Info) is “confirmed” (“No” in step 519), the optimum value of the suction force suitable for the recording paper 38 is obtained from the paper information. Thereafter, the control means 7 switches the duty of the suction device 4 to the optimum value (the suction force is a value suitable for the recording paper) and can simultaneously operate the transport of the recording paper 38 and the movement of the carriage 21 ( Step 520, FIG. 8 (1)).

  Next, the control means 7 moves the carriage 21 and stops the carriage 24 at the right end surface position of the recording paper 38. At this time, the distance from the carriage standby position 24 to the stop position where the carriage 21 is stopped is measured by an encoder provided on the path along which the carriage 21 moves, and stored as a variable b1. (Step 520, FIG. 8 (2)) The control means 7 can detect the sheet width of the recording sheet 38 from the variables a1 and b1.

  Note that the control means 7 can obtain a suction force suitable for the recording paper 38 based on the set paper information even during the operation of the forming means 6. Further, the suction force suitable for the recording paper 38 can be switched even during the operation of the forming means 6.

  Thereafter, the control means 7 transports the leading end of the recording paper 38 to the position of the second transport amount m as the second stage transport (step 521, FIG. 8 (3)). At this time, since the suction device 4 is switched to a suction force suitable for the recording paper 38, the recording paper 38 can be transported without returning the carriage 21 to the carriage standby position 24.

  The control means 7 calculates the amount of movement of the recording paper 38 (step 522), and determines whether the leading end of the recording paper 38 has reached the position of the second transport amount m (step 523). If the movement amount is less than the second conveyance amount m, the conveyance is continued, and if the movement amount is the second conveyance amount m or more, the conveyance of the recording paper 38 is stopped (step 524, FIG. 8 (3)).

  Simultaneously with the conveyance of the recording paper 38 to the position of the second conveyance amount m, the carriage 21 on the recording paper 38 is moved to the left end surface of the recording paper 38 (position where the carriage sensor 22 detects “no paper”). Let The control means 7 measures the distance from the carriage standby position 24 to the stop position where the carriage 21 is stopped by an encoder provided on the path along which the carriage 21 moves, and stores it as a variable a2 (step 525, FIG. 8 (3)). ). Since the conveyance of the recording paper 38 and the skew detection can be performed at the same time without returning the carriage 21 to the carriage standby position 24, the time required for skew detection can be reduced and the time required for forming can be reduced.

  Thereafter, after the carriage 21 is returned to the carriage standby position 24, the suction force of the suction device 4 is switched to the minimum (step 509, FIG. 8 (4)).

  Next, the control means 7 compares the saved variables a1 and a2 (step 510). If it is determined as a result of the comparison that no skew has occurred, the leading end of the recording paper 38 is returned and conveyed to the registration standby position 24 (if “Yes” in step 510, FIGS. 7 (7) and 8 (8)). 5)). The subsequent processing procedure will be described later with reference to FIG. 9 (processing C in the figure).

  On the other hand, if it is determined as a result of the comparison that skew has occurred (in the case of “No” in step 510), the leading end of the recording paper 38 is transported back to the position of the first transport amount n and again skewed. Detection and skew correction are repeated (steps 501 to 510).

  The control means 7 predefines the maximum number of repetitions as a constant ReTryMax. The variable count and the constant ReTryMax are compared (step 511). If the variable count is less than the constant ReTryMax, 1 is added to the variable count (step 512), and the leading edge of the recording paper 38 is brought to the position of the first transport amount n. Return (steps 513 to 516, FIG. 7 (1) and FIG. 8 (1)).

  Thereafter, skew detection and skew correction are repeated (steps 501 to 516). At this time, the variable count and ReTryMax are compared (step 511), and if the value of the variable count is greater than or equal to ReTryMax, the suction device 4 is turned off (stopping suction) (step 517), and a roll forming error is detected. (Step 518).

The image forming apparatus 1 performs processing for prompting the user to set the roll paper 39 again on the paper feed tray 30 when a roll forming error occurs. (Step 518)
As described above, the skew detection and skew correction processing during the operation of the forming means 6 is completed (processing C in the drawing and “END” in step 518).

  Next, a specific processing procedure until an image can be formed after skew detection and skew correction will be described with reference to FIG. FIG. 9 shows steps 601 to 608 of the processing procedure after skew detection (processing C in FIG. 6).

  When it is determined that no skew has occurred (step 510 in FIG. 6, processing C), the control unit 7 determines whether the carriage 21 is positioned at the carriage standby position 24 (step 601). If the carriage 21 is not located at the carriage standby position 24 (“No” in step 601), the carriage 21 is returned to the carriage standby position 24 (step 602).

  Thereafter, in order to return the leading end of the recording paper 38 to the registration standby position 24, the registration rollers 32 and the like are reversely rotated and the recording paper 38 is returned and conveyed (step 603). The control means 7 calculates the amount of movement of the recording paper 38 (step 604) and determines whether the leading edge of the recording paper 38 is located at the registration standby position 24 (step 605).

  When the leading end of the recording paper 38 is positioned at the registration standby position 36, the conveyance is stopped and at the same time the suction of the suction device 4 is stopped (step 606).

  Further, the control means 7 determines whether or not the paper information is confirmed by using a flag (variable Info) of the paper information (step 607). If the flag is “unconfirmed”, it waits until it becomes “confirmed”. (Yes in step 607).

The image forming apparatus 1 is in a state in which an image can be formed when the flag is “confirmed” (in the case of “No” in step 607). Thereafter, the image forming apparatus 1 performs internal processing so that a request to start printing can be accepted. (Step 608)
It should be noted that the present invention is not limited to the configuration shown here, such as a combination with other elements in the configuration described in the above embodiment. These points can be changed without departing from the gist of the present invention, and can be appropriately determined according to the application form.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Image forming means 21 Carriage 24 Carriage standby position 3 Conveying apparatus 38 Recording paper 39 Long recording medium (roll paper)
4 suction device 51 user interface means 52 confirmation means 53 screen display means 6 forming means 61 means for detecting skew 62 means for correcting skew 7 control means

JP 2004-277057 A JP 2010-058376 A

Claims (8)

An image forming unit that conveys a long recording sheet and prints on the recording sheet by a printing unit provided in a carriage that moves in the width direction of the recording sheet;
Forming means including means for detecting skew of the recording paper and means for correcting skew until the recording paper is set in a printable state after the recording paper is set for replacement of the recording paper, etc.
User interface means capable of setting paper information and the like of the recording paper;
An image forming apparatus comprising: a control unit that simultaneously performs an operation of the forming unit and an operation of a confirmation unit that prompts input to the user interface unit. The confirmation means includes screen display means,
The image forming apparatus according to claim 1, wherein the screen display unit displays a screen that prompts input.   The image forming apparatus according to claim 2, wherein the control unit changes an operation of the forming unit according to a setting of the sheet information and the like.   4. The image forming apparatus according to claim 2, wherein the control unit determines whether the setting of the sheet information or the like is confirmed during the operation of the forming unit. 5.   The image forming apparatus according to claim 4, wherein the control unit continuously displays a screen that prompts the input of the screen display unit when the setting of the sheet information or the like is not finalized. The image forming unit has a suction device that sucks and fixes the recording paper,
The control means sets the suction force of the suction device suitable for the recording paper based on the paper information or the like when the setting of the paper information or the like is confirmed during the operation of the forming means. The image forming apparatus according to claim 4, wherein: The forming means operates the means for detecting the skew before operating the means for correcting the skew;
The control means, when operating the means for detecting the skew, performs skew detection by the carriage moving from a carriage standby position outside the recording paper width,
When the setting of the recording paper is confirmed, the control means performs the skew detection not from the carriage standby position but from within the range in the width direction of the recording paper. The image forming apparatus according to claim 6. The forming means operates the means for detecting the skew before operating the means for correcting the skew;
The control means, when operating the means for detecting the skew, performs skew detection by the carriage moving from a carriage standby position outside the recording paper width,
The image forming apparatus according to claim 6, wherein when the setting of the recording sheet is not confirmed, the control unit performs the skew detection from the carriage standby position in the subsequent skew detection.

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