JP2008056445A - Recording device and medium conveyance method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording device and a medium conveyance method for feeding a preceding medium and a following medium continuously while keeping a necessary interval between them and improving throughput. <P>SOLUTION: When feeding a paper over conveyance distance a, the preceding paper is conveyed up to a position for controlling interval between pages so that conveyance speed of an ASF motor becomes the same speed as conveyance speed of a PF motor, then, driving of the ASF motor is stopped, and driving of the ASF motor is restarted just after the preceding paper is conveyed by distance Lgap for controlling interval between pages. During this period, conveyance speed of the PF motor is changed from V1 to higher speed V2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a recording apparatus and a medium conveying method for feeding and conveying a medium and recording on a medium being conveyed.

  2. Description of the Related Art Conventionally, some printers that are one type of recording apparatus include an automatic sheet feeder (hereinafter referred to as ASF (Auto Sheet Feeder)) (for example, Patent Document 1). The paper set in the ASF is fed by driving the ASF when printing is started, and is automatically cued to the print start position.

  The ASF starts feeding the next succeeding sheet when the preceding sheet is fed and one sheet is discharged. However, in this paper feeding method, after waiting for the preceding paper to be discharged, the feeding of the next succeeding paper is started. A relatively long waiting time occurs. This has been one cause of reducing the printing throughput.

  In order to solve this type of problem, for example, Patent Document 1 discloses a printing apparatus (recording apparatus) that continuously conveys a preceding sheet and a succeeding sheet with a predetermined gap between the preceding sheet and the succeeding sheet. ) Is disclosed. According to this printing apparatus, the paper discharge operation for the preceding paper and the paper feeding operation for the subsequent paper are simultaneously performed, the waiting time until the start of printing on the subsequent paper after the printing of the preceding paper is completed is shortened, and the printing throughput is increased. Can be improved.

  Incidentally, a paper detection sensor for detecting the leading edge of the paper is disposed between the paper feed roller and the paper feed roller of the ASF in order to cue the fed paper. However, if the paper is continuously fed and a gap is not secured between the preceding paper and the succeeding paper, the paper detection sensor cannot detect the leading edge of the paper. In addition, there is a concern about the double feeding in which the trailing edge of the preceding sheet and the leading edge of the succeeding sheet are partially overlapped. For this reason, even when sheets are continuously fed, it is necessary to leave a predetermined interval between the preceding sheet and the succeeding sheet.

For example, in Patent Document 1, in order to prevent double feeding of sheets, the conveyance start timing of the subsequent sheet (recording sheet on the next page) is performed after the trailing edge of the preceding sheet (recording sheet on the current page) passes the conveyance roller. In this configuration, a gap is secured between the preceding sheet and the succeeding sheet. Specifically, the configuration is such that the conveyance of the succeeding sheet is started after waiting for the trailing edge of the preceding sheet to pass the conveying roller. Then, when the preceding sheet is fed, the succeeding sheet is conveyed synchronously by the same conveying amount as the preceding sheet.
JP 2005-96450 A

  However, in the technique of the cited document 1, although the conveyance speed is not mentioned, there is a recording apparatus in which the conveyance speed of the paper is determined according to the conveyance distance. In this case, for example, when paper feeding is performed in which the trailing edge of the preceding paper passes the paper feeding roller, the preceding paper is fed to the feeding roller and the transport direction from here until the trailing edge of the paper passes before the paper feeding roller. Since it is nipped with the paper feed roller located on the downstream side, the feed speed by the paper feed roller and the transport speed by the paper feed roller so that excessive tension and excessive slack are not given to the preceding paper. Must be driven at approximately the same speed. Therefore, if the conveyance speed by the paper feed roller is low, the conveyance speed (first conveyance speed) of the paper feed roller must be reduced accordingly.

  If the trailing edge of the preceding paper passes the paper feed roller, the preceding paper is released from the nip of the paper feed roller, so that the transport speed (second transport speed) of the preceding paper is matched with the transport speed of the paper feed roller. There is no need. However, in the technique of Patent Document 1, the preceding sheet is conveyed to the conveyance end position while maintaining the same conveyance speed as the previous conveyance speed (first conveyance speed). Therefore, when the conveyance speed until the trailing edge of the preceding sheet passes the sheet feeding roller is extremely low, the preceding sheet is conveyed at a low speed to the conveyance end position, which causes a problem that throughput decreases. .

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a recording apparatus capable of continuously feeding a preceding medium and a succeeding medium while opening a necessary gap and improving throughput. And providing a medium conveying method.

  The present invention includes a recording unit including a feeding unit that feeds a medium, a conveying unit that conveys the medium fed by the feeding unit, and a recording unit that records on the medium conveyed by the conveying unit. In the apparatus, the preceding medium fed first is transported by both the feeding unit and the transporting unit, and the preceding medium is transported to a predetermined position where it is not transported by the feeding unit, and then the feeding After the feeding means is stopped or decelerated and waits until the distance between the preceding medium and the succeeding medium reaches a predetermined distance, acceleration of the succeeding medium by the feeding means is started and the preceding medium and the succeeding medium are continuously conveyed. Control means for drivingly controlling the feeding means and the conveying means so that the control means performs the preceding by the feeding means and the conveying means when the preceding medium passes through the predetermined position. It is the conveyance speed of the medium A speed at which one transport speed is different from a second transport speed that is a transport speed of the subsequent medium by the transporting means or a transport speed of the preceding medium by the transporting means after the start of acceleration of the subsequent medium by the transporting means. The condition is that the control is performed to shift the transport speed from the first transport speed to the second transport speed.

  According to this, when the preceding medium transported by both the feeding unit and the transporting unit is transported to a predetermined position where it is not transported by the feeding unit, the driving of the feeding unit is stopped or decelerated and the preceding medium and After waiting for a predetermined distance from the succeeding medium, acceleration of the succeeding medium by the feeding unit is started. The control means waits until the first conveyance speed of the preceding medium conveyed by both the feeding means and the conveying means and the distance between the preceding medium and the succeeding medium reach a predetermined distance, and then the subsequent medium by the feeding means is performed. After the start of acceleration, under the condition that the conveyance speed of the subsequent medium by the feeding means or the second conveyance speed, which is the conveyance speed of the preceding medium by the conveyance means, is different, the conveyance means is changed from the first conveyance speed to the second conveyance speed. Shift to. The feeding unit and the conveying unit are cooperatively controlled so that, for example, the medium is transported at substantially the same speed so that the medium is not excessively pulled or loosened while the medium is being transported. Although it is necessary, after the preceding medium is transported to a position where it is not transported to the feeding means, there is no need for cooperative control. After this cooperative control is no longer necessary, the transport speed of the preceding medium is shifted from the first transport speed to the second transport speed. For example, when the second transport speed is higher than the first transport speed, the transport means is accelerated from the first transport speed to the second transport speed, and the transport of the preceding paper is terminated early, for example, to the preceding medium. The next recording can be started early. Accordingly, the preceding medium and the succeeding medium can be continuously conveyed with a necessary interval, and the conveyance speed can be changed at a high speed, so that the throughput can be improved. Note that, as a method of shifting the speed from the first transport speed to the second transport speed, a configuration in which the transport means is temporarily stopped when the transport means is changed from the first transport speed to the second transport speed is also conceivable. Since the speed of the conveying means is changed without being temporarily stopped, the throughput can be easily improved as compared with the structure of temporarily stopping the conveying means.

  In the recording apparatus according to the aspect of the invention, the first transport speed may be set so that the preceding medium is transported to stop at the predetermined position by both the feeding unit and the transport unit. It is the transport speed of the feeding means and the transport means when transporting without stopping from the stop position immediately before transport to the predetermined position, and the second transport speed includes the subsequent medium and the preceding medium. When the distance from the succeeding medium reaches the predetermined distance, the feeding means starts accelerating and transports without stopping until the next stop position, or the preceding medium is transported without stopping. The acceleration from the first transport speed can be started at least from the acceleration start position after the predetermined position without stopping from the position at the time of zero speed on the acceleration gradient extension of the acceleration to the next stop position. One of the transport speeds of the transport means when sending, and the control means may execute control satisfying a relationship in which the second transport speed is higher than the first transport speed according to a transport distance. preferable.

  According to this, when the preceding medium is transported to stop at a predetermined position by both the feeding unit and the transporting unit, the preceding medium does not stop from the stop position immediately before the transport to the predetermined position, The sheet is conveyed at the first conveyance speed by the feeding unit and the conveyance unit. When the distance between the preceding medium and the succeeding medium reaches a predetermined distance, acceleration is started by the feeding means and the next medium is transported at the second transport speed by the feeding means without stopping until the next stop position. Is done. Alternatively, the preceding medium can be accelerated from the first transport speed at least from the acceleration start position after the predetermined position without stopping from the position at zero speed on the acceleration gradient extension to the next stop position. When transporting, the preceding medium is transported at the second transport speed by the transport means. The control means executes control that satisfies a relationship in which the second transport speed is higher than the first transport speed. That is, when the second transport speed at which the feeding unit transports the subsequent medium satisfies the relationship of being higher than the first transport speed, or the second transport speed at which the transport unit transports the preceding medium is higher than the first transport speed. When satisfying this relationship, the control means shifts the conveyance means from the first conveyance speed to the second conveyance speed from the acceleration start position.

  In the recording apparatus of the present invention, the first speed control data in which the first transport speed is set as the target speed and the speed according to the position value is set, and the second transport speed is set as the target speed and the position is set. Storage means for storing the second speed control data in which the speed according to the value of the second speed control data is set, and the control means refers to when shifting the transport means from the first transport speed to the second transport speed. Preferably, the speed control data to be switched is switched from the middle of the first speed control data to the corresponding middle of the acceleration process of the second speed control data.

  According to this, in the shift control for shifting the speed from the first transport speed to the second transport speed, the reference speed control data is shifted from the middle of the first speed control data to the corresponding middle of the acceleration process of the second speed control data. This is done by switching. Therefore, it is not necessary to prepare speed control data dedicated to shift control. For example, it is desirable to switch from the target speed of the first speed control data to the middle corresponding to the target speed in the acceleration process of the second speed control data.

  In the recording apparatus of the present invention, the control unit searches the second speed control data to obtain a position where the same speed as the target speed of the first speed control data is set, and the preceding medium is the When transporting a predetermined position, first, the transporting means is accelerated to the first transport speed by controlling the speed according to the first speed control data, and maintained at a constant speed at the first transport speed. It is preferable to perform speed control according to second speed control data from a continuation of the value of the position obtained by the search from a predetermined acceleration start position that has passed the area transported by both the means and the transport means.

  According to this, the second speed control data is searched to obtain a position where the same speed as the target speed of the first speed control data is set, and the predetermined acceleration is performed during the constant speed after accelerating to the first transport speed. When the start position is reached, speed control is performed from the first transport speed to the second transport speed by performing speed control according to the second speed control data from the continuation of the position value obtained by the search. Thus, since the speed change control is performed by combining the two speed control data, it is not necessary to prepare speed control data dedicated to the speed change.

  The recording apparatus of the present invention further includes storage means for storing speed control data in which a speed according to a position value in a shifting process from the first transport speed to the second transport speed is set, and the control The means preferably accelerates the preceding medium from the first transport speed to the second transport speed by controlling the transport means to a speed corresponding to a position value in the speed control data in the speed change process.

  According to this, the shift control from the first transport speed to the second transport speed is performed by controlling the transport means so that the speed according to the position value is obtained according to the speed control data in the shift process. Since only the speed control data in the shifting process is followed, there is no need to perform special processing such as combining the two speed control data.

  The recording apparatus of the present invention further includes storage means for storing data of a calculation formula capable of calculating a speed according to a position value in a shifting process from the first transport speed to the second transport speed, Preferably, the control unit performs the shift control by controlling the transport unit so that the speed is calculated according to the position value using a calculation formula in the shift process.

  According to this, the transport unit is controlled to use the calculation formula stored in the storage unit so as to obtain a speed calculated according to the position value, thereby shifting from the first transport speed to the second transport speed. Shift control is performed. Since the speed corresponding to the position value is obtained by calculation, data of a calculation formula having a relatively small data capacity may be stored in the storage means.

  In the recording apparatus according to the aspect of the invention, the control unit may change the transport unit from the first transport speed to the second transport speed under a condition that the second transport speed is lower than the first transport speed. It is preferable not to perform the shift control for shifting.

  According to this, under the condition that the second transport speed is lower than the first transport speed, the shift control for shifting the first transport speed to a lower transport speed is not performed, and the first transport speed is advanced. The medium is conveyed. Therefore, throughput can be improved.

  The recording apparatus of the present invention further includes a first drive source that drives the feeding unit and a second drive source that drives the transport unit, and the control unit includes the first drive source and the second drive source. It is preferable to drive-control the drive source.

According to this, since the feeding means and the conveying means are driven by separate drive sources, it is easy to control the feeding means and the conveying means individually.
In the recording apparatus according to the aspect of the invention, the second transport speed may be a transport distance from the predetermined position of the first drive source to the next stop position, or a position from the position of the second drive source at the time of zero speed. It is preferable to depend on the transport distance to the stop position.

  According to this, the second transport speed is the transport distance from the predetermined position of the first drive source to the next stop position, or the position at the zero speed on the acceleration gradient extension of the second drive source to the next stop position. Therefore, when this transport distance is relatively long, it can be transported at a higher speed than when it is short.

  In the recording apparatus of the present invention, a minimum distance corresponding to a total of a movement distance necessary for acceleration up to the conveyance speed and a movement distance necessary for deceleration from the conveyance speed is determined. The highest transfer speed among the transfer speeds that satisfies that the transfer distance from the transfer start position of the transfer that passes through the predetermined position to the position at which shifting from the first transfer speed to the second transfer speed starts is not less than the minimum distance. It is preferable to select the first one and determine the first transport speed.

According to this, the fastest transport speed that satisfies that the transport distance is equal to or greater than the minimum distance is selected, so that the preceding medium can be transported at a transport speed as high as possible.
In the recording apparatus of the present invention, the first transport speed is determined by selecting a lower one of the transport speeds separately determined by the feeding unit and the transport unit, and the second transport speed. Is preferably determined by selecting the fastest transport speed satisfying that the remaining transport distance transported at the first transport speed is not less than the minimum distance.

  According to this, even if the first transport speed is suppressed to a low speed from the minimum distance condition and the condition that the transport speed is substantially the same between the feeding unit and the transport unit, the first transport speed is higher than the first transport speed. Since it is possible to shift to the second transport speed, the throughput can be improved.

  The present invention further includes a feeding unit that feeds the medium, a conveying unit that conveys the medium fed by the feeding unit, and a recording unit that records the medium conveyed by the conveying unit. A medium transport method in the recording apparatus, wherein a predetermined position at which the preceding medium to be fed first is not transported by the transport means from a position in an area where both the transport means and the transport means are transported. When transporting the preceding medium so as to pass, the preceding medium is transported by both the feeding unit and the transporting unit, and after the preceding medium is transported to a predetermined position where it is not transported by the transporting unit, The step of stopping or decelerating the driving of the feeding unit, and waiting until the interval between the preceding medium and the succeeding medium reaches a predetermined distance, and then the acceleration of the succeeding medium by the feeding unit is started and the preceding medium and the succeeding medium are started. A control step of driving and controlling the feeding means and the conveying means so as to continuously convey the body, a first conveying speed of a preceding medium conveyed by both the feeding means and the conveying means, After the start of acceleration of the succeeding medium by the feeding means, the first transport speed is different from the transport speed of the succeeding medium by the feeding means or the second transport speed that is the transport speed of the preceding medium by the transport means. And a shift step for performing shift control for shifting from the transport speed to the second transport speed. According to this, the same effect as the invention of the above recording apparatus can be obtained.

Hereinafter, an embodiment in which the present invention is embodied in a printer will be described with reference to FIGS. FIG. 2 is a perspective view of the printer in this embodiment.
The printer 11 as a recording apparatus is, for example, an ink jet printer. The printer 11 is equipped with an automatic sheet feeder (hereinafter referred to as ASF 13) as a feeding means for feeding paper P as a medium on the back side of the main body 12. A paper guide 17 including a paper feed tray 14, a hopper 15, an edge guide 16 and a paper support 14a is attached to the ASF 13. The ASF 13 includes a paper feed drive mechanism that feeds the paper set in the paper guide 17 into the main body 12 one by one.

  A carriage 18 that reciprocates in the main scanning direction (X direction in FIG. 2) is provided in the main body 12, and a recording head 19 is provided below the carriage 18. In the process of moving the carriage 18 in the main scanning direction X, a recording operation for ejecting ink from the recording head 19 to the paper P and a paper feeding operation for transporting the paper P in the sub-scanning direction Y by a predetermined transport amount are alternately repeated. As a result, printing on the paper P is performed. The printed paper P is discharged from a paper discharge port 12 </ b> A that opens at the front lower portion of the main body 12. The carriage 18 and the recording head 19 constitute a recording unit.

  FIG. 1 shows an automatic paper feeder and a transport device. As shown in FIG. 1, a hopper 15 is supported on the upper surface side of the paper feed tray 14 disposed obliquely on the back surface of the main body so as to be tiltable within a predetermined angle range about an upper end shaft 15a. Yes. The hopper 15 is urged in a direction away from the paper feed tray 14 (upper left direction in FIG. 1) by a compression spring 21 interposed between the paper feed tray 14.

  Near the lower end of the hopper 15, a cylindrical sheet feeding roller 22 is disposed so as to be rotatable about a rotation shaft 23. The hopper 15 reciprocates between a retracted position shown in FIG. 1A and a paper feeding position shown in FIG.

  A guide portion 14b is provided on the upper surface of the downstream end portion (left side in FIG. 1) of the paper feed tray 14. A retard roller 24 is disposed at a position facing the paper feed roller 22 in the vicinity of the upper end of the guide portion 14b. The retard roller 24 is provided such that it can be driven and rotated with respect to the paper feed roller 22 in a state where a constant rotational load is applied by a torque limiting mechanism such as a torque limiter. In the present embodiment, the hopper 15 and the retard roller 24 are configured to operate in conjunction with each other.

  At a position downstream of the ASF 13 in the paper conveyance direction, a carriage 18 on which the ink cartridge 26 is mounted is provided so as to be movable along the guide shaft 27 in the main scanning direction X (direction perpendicular to the paper surface in FIG. 1). A platen 28 is arranged below the recording head 19 with a predetermined interval. On both sides of the platen 28 sandwiched in the sub-scanning direction (the left-right direction in the figure), a paper feed roller 29 and a paper discharge roller 30 are respectively disposed.

  The paper feed roller 29 includes a pair of a transport driving roller 29a and a transport driven roller 29b, and the paper discharge roller 30 includes a pair of a paper discharge drive roller 30a and a paper discharge driven roller 30b. In the present embodiment, the conveyance drive roller 29a and the paper discharge drive roller 30a are driven by a PF motor 58 (paper feed motor) (see FIG. 5), which is the same drive source, and cooperate with each other to feed the paper P.・ Discharge paper. The paper feed roller 22 is driven by the ASF motor 56 and cooperates with the paper feed roller 29 to feed and feed the paper P.

  Between the paper feed roller 22 and the paper feed roller 29, there is a lever 31 whose lower end extends to reach the paper transport path, and an optical sensor unit 32 whose detection target is the upper end of the lever 31. A paper detection sensor 33 is provided. In the state where there is no paper P1 that presses the lower end of the lever 31, the paper detection sensor 33 returns to the original position shown in FIG. 1A by the biasing force of the spring and is turned off. When P1 pushes the lower end of the lever 31 and rotates it as shown in FIG. Specifically, the sensor unit 32 includes a light emitter and a light receiver, and the lever 31 that has blocked the light emitted from the light emitter is pushed by the paper P1 to rotate, and the light is received by the light receiver. In this configuration, the paper detection sensor 33 is turned on.

  The retard roller 24 has a retracted position separated from the outer peripheral surface of the paper feed roller 22 as shown in FIG. 1A and a paper feed position abutting on the outer peripheral surface of the paper feed roller 22 as shown in FIG. It can be moved up and down. At the time of standby shown in FIG. 1A where printing is not performed, the retard roller 24 moves downward and is disposed at a retracted position away from the paper feed roller 22. On the other hand, at the time of printing shown in FIG. 1B, the retard roller 24 moves upward and is disposed at a position where the paper can be nipped between the paper feed roller 22 and the hopper 15 urges the compression spring 21 accordingly. The paper P stacked on the hopper 15 is pressed against the paper feed roller 22 by tilting in the direction.

  The uppermost sheet P of the paper P urged by the paper feed roller 22 as the hopper 15 moves upward is sandwiched between the paper feed roller 22 and the retard roller 24 by the rotation of the paper feed roller 22. Paper is fed. In this paper feeding process, the paper P biased to the paper feeding roller 22 by the balance between the rotational resistance of the retard roller 24, the frictional resistance of the peripheral surface of the paper feeding roller 22, and the frictional resistance of the surface of the paper P is Of these, only the topmost sheet P1 is separated from other sheets and fed.

  The retard roller 24 and the hopper 15 return to the retracted position when there is no next page to be fed next when the cueing of the paper is finished. Therefore, as long as there is a next page of paper to be fed, the hopper 15 and the retard roller 24 are arranged at the paper feed position shown in FIG. As a result, the paper is continuously fed with a slight paper gap.

  When the paper feed roller 22 is continuously rotated, the preceding paper P1 fed first and the subsequent paper P2 of the next page are continuously fed without any gap. However, if there is no predetermined gap between the preceding paper P1 and the succeeding paper P2, the lever 31 will be in FIG. 1A even if the trailing edge of the preceding paper P1 passes the lower end of the lever 31 of the paper detection sensor 33. It is not possible to return to the indicated origin position, and the leading edge of the succeeding paper P2 cannot be detected.

  As a method of opening a gap that can be detected by the paper detection sensor 33 between the papers P1 and P2, every time the preceding paper P1 is fed to a position where it is not nipped between the paper feed roller 22 and the retard roller 24, There is a method of moving the hopper 15 and the retard roller 24 to the retracted position. According to this method, during the time when the hopper 15 and the retard roller 24 are retracted, the feeding start timing of the succeeding sheet is delayed, and a gap can be formed between the preceding sheet and the succeeding sheet. However, even if evacuation is performed for a short time of 1 second or less, if the evacuation is performed, for example, when paper ejection or long paper feed is performed, the gap between the preceding paper and the succeeding paper becomes too wide, and the printing throughput is reduced. Cause it. For this reason, in this embodiment, the hopper 15 and the retard roller 24 are held in the paper feed position. In this embodiment, interpage control, which is transport control that secures a gap between the preceding sheet and the succeeding sheet, is employed. The contents of this interpage control will be described later.

  The leading end of the fed paper P1 passes between the paper feed rollers 29 and is cued to the recording start position between the carriage 18 and the platen 28. A large number of nozzles (nozzle groups) for ejecting ink are opened on the lower surface of the recording head 19, and the position of the nozzle (referred to as the most upstream nozzle) in the transport direction in the nozzle group is the head reference position ( The position of the sheet P1 is determined by transporting the sheet P1 to a position where the print start position on the sheet coincides with the head reference position.

  The cueing position is determined according to the layout conditions such as the margin (top margin) and borderless printing that determine the printing start position on the paper. When feeding paper, the transport distance according to the cueing position is specified. Is done. After the feeding of the paper P1 is completed (that is, after cueing), the printing operation of the recording head 19 and the paper feeding operation are alternately performed, and the printing proceeds.

  In this embodiment, the paper conveyance until the fed paper is cued is “paper feeding operation”, the paper conveyance until the cueing paper is printed is “paper feeding operation”, and the printing is finished. Paper conveyance until the trailing edge of the paper is no longer detected by the paper detection sensor 33 is defined as “paper discharge operation”. When the paper has already been transported to a position where the trailing edge of the paper is no longer detected by the paper detection sensor 33 when printing is finished, the paper is not ejected and the subsequent paper is fed. The paper discharge roller 30 rotates in conjunction with the paper supply operation, and the preceding paper is discharged.

  FIG. 3 is a schematic view of the automatic paper feeder (ASF) and the transport device (PF) as viewed from the side. Various positions and distances defined in the interpage control process will be described with reference to FIG. The most upstream nozzle position of the recording head 19 is the head reference position H. The distance between the head reference position H (the most upstream nozzle) and the paper feed roller nip point is “La”, the distance between the paper feed roller nip point and the paper detection sensor 33 is “Lb”, and the paper detection sensor 33 to the paper feed roller nip point (feed) The distance between the paper roller 22 and the retard roller 24) is “Lc”.

  When the preceding paper P1 is conveyed to the position of FIG. 3, the paper P1 is released from the nip of the paper feed roller 22. For this reason, after the sheet is conveyed to the position shown in FIG. 3, it is not necessary to drive the sheet feeding roller 22 and the sheet feeding roller 29 (and the sheet discharging roller 30) at a driving speed capable of conveying the sheet at the same speed. In other words, while the rear end side of the paper P1 is nipped by the paper feed roller 22, the paper P1 is nipped at two locations of the paper feed roller 22 and the paper feed roller 29 during paper feeding. During this period, it is necessary to drive the paper feed roller 22 and the paper feed roller 29 synchronously at the same speed. If the synchronization is not performed at the same speed, the sheet P1 is undesirably conveyed in the sheet conveyance process because the sheet P1 is excessively pulled or loosened at the portion between the sheet feeding roller 22 and the sheet feeding roller 29. Because.

  However, after the end (rear end) on the upstream side in the conveyance direction of the sheet P1 is released from the nip of the sheet feeding roller 22, the preceding sheet P1 and the next page sheet P2 (following sheet) are individually conveyed. It is not necessary to synchronize the conveyance of the paper feed roller 22 and the paper feed roller 29. In the present embodiment, when the trailing edge of the preceding paper P1 reaches a position released from the nip of the paper feed roller 22, the rotation of the paper feed roller 22 is temporarily stopped, and during this stop, the paper P1 is fed by the paper feed roller 29. After the conveyance is advanced and a predetermined gap is secured between the preceding paper P1 and the succeeding paper P2, the rotation of the paper feeding roller 22 is resumed and the feeding of the succeeding paper P2 is resumed. . By performing such inter-page control processing, a necessary gap is secured between the sheets P1 and P2. Since a predetermined gap is secured between the sheets P1 and P2, the leading edge of the succeeding sheet P2 is detected and then turned on after the sheet detection sensor 33 is turned off by the gap. It can be detected by the sensor 33. Therefore, it is possible to cue the succeeding paper P2, which is performed by transporting a predetermined distance from the reference position based on the position detected by the paper detection sensor 33.

  This is a stop position where the rotation of the paper feed roller 22 is stopped at a position where the leading edge of the subsequent paper P2 protrudes from the paper feed roller nip point by the distance “Ld” after the preceding paper P2 is released from the nip by the paper feed roller 22. The interpage control position G is set. This pop-out distance “Ld” corresponds to a margin at which the paper feed roller 22 can be stopped after the preceding paper P1 is reliably released from the nip of the paper feed roller 22. A position on the paper P1 facing the head reference position H when the trailing edge of the preceding paper P1 reaches the interpage control position G is defined as an interpage control position Ng. In this embodiment, since the position of the sheet P1 is managed at a position on the sheet opposite to the head reference position H, the position on the downstream side in the transport direction by the distance (La + Lb + Lc−Ld) from the rear end of the sheet P1 is the head. When the reference position H is reached, it is determined that the sheet has reached the interpage control position Ng where the trailing edge of the sheet is positioned at the interpage control position G.

  In FIG. 3, the distance “Lgap” is a distance (hereinafter referred to as a gap distance Lgap) that should separate the sheets P1 and P2. After the paper P1 is fed by the gap distance “Lgap” from the interpage control position, the rotation of the paper feed roller 22 that has been temporarily stopped is resumed. “Psize” is a paper length (length in the transport direction) designated by the printer driver. The position obtained by subtracting the distance (La + Lb + Lc−Ld) from the sheet length “Psize” is the interpage control position Ng. Therefore, the interpage control position Ng represented by the distance Nx from the leading edge of the paper P1 changes according to the paper length “Psize”. Here, “Nx” indicates the paper feed amount of the paper P1 from the position where the leading edge of the paper P1 reaches the head reference position H. In the present embodiment, the paper transport distance (paper feed amount) from the time when the leading edge of the paper P1 reaches the head reference position H is counted by the paper feed amount counter 65 (see FIG. 5), and the paper P1 is calculated with this count value. Is managing the position. When the paper feed amount Nx, which is the count value of the paper feed amount counter 65, has reached a value Ng which is (Psize− (La + Lb + Lc−Ld)), it is determined that the paper P1 has reached the interpage control position Ng.

Next, the electrical configuration of a printer including an automatic paper feeder will be described with reference to FIG.
As shown in FIG. 5, the printer 11 includes a control unit 40 that performs various controls. The control unit 40 includes an interface 41 that is communicably connected to a host computer 35 (PC). A CPU 43, an ASIC 44 (Application Specific IC), a ROM 45, a RAM 46, a nonvolatile memory 47, and the like are connected to the bus 42 connected to the interface 41. The CPU 43 executes a program stored in the ROM 45 to perform paper feed control, paper feed control, print control, paper discharge control, and the like.

  The host computer 35 includes a printer driver (not shown), and the paper size, paper type, and layout set by the user by operating the input device 35b on the print setting screen displayed on the monitor 35a based on a user input instruction. Get various print parameters. When receiving a print execution instruction from the input device 35b, the printer driver performs predetermined processing to generate print data. Specifically, the printer driver performs resolution conversion processing for converting image data to be printed from display resolution to print resolution, for example, color conversion processing from the RGB color system to the CMYK color system, and gradation values that can be expressed by the printer 11. A halftone process for conversion and a rasterization process (microweave process) for rearranging in the order of data to be transferred to the printer 11 (ejection order) are sequentially performed. Then, the print data is generated by attaching a command to be directed to the obtained print image data to the header. In addition to the command, this header includes printing parameters such as the paper size, and parameters of the target speed and transport distance (paper feed amount, etc.) at the time of paper transport indicating the contents to be specified by the command.

  The CPU 43 inputs print data from the printer driver of the host computer 35 through the interface 41 and the bus 42, and acquires the paper length Psize from the header in the print data first received from the host computer 35. Further, the CPU 43 interprets commands included in the header of the print data and, for example, various commands such as paper feed / paper feed / paper discharge and the specific contents of the instructions are indicated by numerical values, for example, paper feed / paper feed.・ Acquire parameters such as target speed and transport distance to which the paper should be transported during paper discharge.

  The ASIC 44 receives print image data other than the header from the print data from the CPU 43, performs image processing on the print image data, and the predetermined gradation used for generating an ejection signal for ejecting ink droplets from the nozzles of the recording head 19. Convert to value bitmap data. The ASIC 44 sends the converted bitmap data to the head driver 48. The head driver 48 controls the recording head 19 based on the bitmap data to eject ink droplets from the nozzles.

  Further, motor drivers 49, 50, 51, 52 are connected to the CPU 43. The CPU 43 drives and controls the carriage motor 55, the ASF motor 56, the sub motor 57, and the PF motor 58 (paper feed motor) via the motor drivers 49 to 52. Specifically, the CPU 43 instructs control data to the motor driver 50, and the motor driver 50 drives and controls the ASF motor 56 so as to rotate at the rotation direction and rotation speed based on the control data. In addition, the CPU 43 instructs control data to the motor driver 52, and the motor driver 52 drives and controls the PF motor 58 to rotate at the rotation direction and rotation speed based on the control data. Further, the carriage motor 55 and the sub motor 57 are driven and controlled for the other motor drivers 49 and 51 in the same manner.

  Further, the output shaft of the PF motor 58 is connected to the transport drive roller 29a and the paper discharge drive roller 30a via a train wheel (not shown) so as to be able to transmit power. The motor driver 52, the PF motor 58, the paper feed roller 29, the paper discharge roller 30, and the like constitute a conveying means.

  Here, the ASF motor 56 rotates the paper feed roller 22. Further, the sub motor 57 is connected to the retard roller 24 and the hopper 15 so as to be able to transmit power, and the retard roller 24 and the hopper 15 are driven so as to be interlocked between the retracted position and the paper feeding position.

  The ASF motor 56 includes a rotary encoder 61 that detects the rotation of the output shaft, and the PF motor 58 includes a rotary encoder 62 that detects the rotation of the output shaft. Each rotary encoder 61, 62 generates and outputs a pulse signal having a period inversely proportional to the rotational speed of the corresponding motor. The CPU 43 is connected to the paper detection sensor 33 and the rotary encoders 61 and 62 as an input system. The CPU 43 receives the on / off signal of the paper detection sensor 33 and the pulse signals from the rotary encoders 61 and 62, respectively. input.

  The CPU 43 includes a paper feed amount counter 65, an ASF counter 66, and a PF counter 67. The paper feed amount counter 65 is reset by the CPU 43 when the paper detection sensor 33 is turned on, and counts the pulse edges of the pulse signal input from the encoder 62 after the reset. Thereafter, when the paper feed amount counter 65 counts a count value corresponding to the paper feed amount of the paper P1, the driving of the ASF motor 56 is stopped and the paper P1 is fed (cueing). After completion of paper feeding, the paper when the count value of the paper feed amount counter 65 subtracts the value corresponding to the distance (La + Lb) shown in FIG. 3 and the leading edge of the paper P1 reaches the head reference position H (the most upstream nozzle). The count value corresponding to the paper feed amount with the position of P1 as the origin is updated. Therefore, the count value Nx of the paper feed amount counter 65 after the end of paper feeding is counted as a value corresponding to the paper feed amount after the leading edge of the paper P1 reaches the head reference position H. The CPU 43 ascertains the position (conveyance position) of the paper P after cueing from the count value Nx of the paper feed amount counter 65.

  The ASF counter 66 counts the pulse edges of the pulse signal input from the encoder 61 that detects the rotation of the ASF motor 56. The ASF counter 66 is reset prior to the start of the driving of the ASF motor 56, and is a measure corresponding to the paper feed amount (conveyance distance) of paper fed by the paper feed roller 22 driven to rotate by the ASF motor 56. Count the numbers. For this reason, the CPU 43 can grasp from the count value of the ASF counter 66 which position in the section from the paper feed start position to the paper feed end position is being fed. The CPU 43 ascertains the transport distance in which the paper having the paper feed start position as the origin is fed (conveyed) from the count value of the ASF counter 66, and controls the speed of the ASF motor 56 according to the transport distance.

  The PF counter 67 counts the pulse edges of the pulse signal input from the encoder 62 that detects the rotation of the PF motor 58. The PF counter 67 is reset before the driving of the PF motor 58 is started, and a count value corresponding to the transport amount (transport distance) of the paper fed by the paper feed roller 29 that is rotationally driven by the PF motor 58. Count. For this reason, the CPU 43 can grasp from the count value of the PF counter 67 which position in the section from the paper feed start position to the paper feed end position the paper being fed is located. The CPU 43 ascertains the distance that the paper having the paper feed start position as the origin is fed (conveyed) from the count value of the PF counter 67 and controls the speed of the PF motor 58 according to the distance. Specifically, the CPU 43 reads the acceleration / deceleration table (shown in FIG. 6) from the nonvolatile memory 47, and according to the acceleration / deceleration table, the ASF motor has a speed (reciprocal of the cycle) according to the distance from the conveyance start position. 56 and PF motor 58 are respectively speed controlled. In this specification, the driving of the ASF motor 56 may be referred to as “ASF driving”, and the driving of the PF motor 58 may be referred to as “PF driving”.

  In the printer 11 of this embodiment, inter-page control is used to ensure a predetermined amount of gap (interval) between the preceding sheet and the following sheet. The ROM 45 stores a program for the interpage control processing routine shown in the flowchart of FIG. The CPU 43 executes this program to execute inter-page control, thereby ensuring a gap between the preceding sheet and the succeeding sheet.

  FIG. 4 is a schematic diagram of a sheet for explaining the inter-page control process executed when the paper feeding that passes through the inter-page control position Ng is performed. In the figure, the upward direction indicated by the arrow is the paper discharge direction (paper feed direction). Although the paper is moved relative to the recording head 19 at the fixed position in the paper feeding direction, the paper is transported. Are drawn to move relative to each other. In FIG. 4, thick lines drawn in the recording head 19 (19A to 19C) indicate nozzle rows.

  Printing is advanced line by line from the leading end side (upper end in FIG. 4) of the paper P1, and the paper feeding amount is intermittently instructed every time one line is printed, and printing is performed downward from the upper end side. Is advanced. At this time, the recording head 19 relatively moves from the upper side to the lower side in FIG. For example, the position of the recording head 19A shown in FIG. 4 indicates the origin position of the paper feed amount “0” where the leading edge of the paper coincides with the head reference position H (the most upstream nozzle). The paper feed amount from the origin position of the paper P1 is counted by the paper feed amount counter 65, so that the CPU 43 can grasp the position of the paper P1 in the transport direction (sub-scanning direction Y) from the count value of the paper feed amount counter 65. It has become.

  The areas indicated by shading in the paper P1 shown in FIG. 4 indicate the print areas PA1 and PA2 on which the recording head 19 performs printing. As shown in the figure, when there is a blank area BA that is not printed between the two print areas PA1 and PA2, the recording head 19B that has finished printing the print area PA1 is the print start position of the print area PA2. The paper P1 is fed by the transport distance “a” so as to move relative to the position of the recording head 19C. When passing through the inter-page control position Ng in this paper feed process, the paper feed operation of this transport distance “a” is the paper of the transport distance “b1” from the paper position at the time of the recording head 19B to the inter-page control position Ng. The operation is divided into a feeding operation and a paper feeding operation of the transport distance “c1” from the interpage control position Ng to the paper position at the time of the recording head 19C. That is, the PF drive is divided into two paper feeding operations of the transport distance “b1” and the transport distance “c1”.

  At this time, the ASF drive is divided into a paper feed operation of the transport distance “b2” to the interpage control position Ng and a paper feed operation of the transport distance “c2” while the PF drive is performed. The PF drive for the transport distance “b1” and the ASF drive for the transport distance “b2” are performed at the same paper transport speed at the same transport distance “b1” and “b2”. This is because the paper P1 is nipped by both the paper feed roller 22 and the paper feed roller 29 in the paper conveyance before reaching the inter-page control position Ng, so the paper feed roller 22 and the paper feed roller 29 are synchronized. This is because it needs to be driven. If the synchronous driving is not performed, the conveyance between the paper feeding roller 22 and the paper feeding roller 29 of the paper P1 may be unsatisfactory or excessive tension may be applied. Therefore, the ASF drive and the PF drive are performed so that the transport distances “b1” and “b2” are equally synchronized and transported at the same transport speed.

  When the PF driving for the transport distance “b1” is finished, the PF driving for the transport distance “c1” is continuously performed. On the other hand, the ASF drive is delayed when the paper P1 is transported by the distance Lgap by the PF drive that has started the paper feeding operation of the transport distance “c1” after the paper feed operation of the transport distance “b2” is finished. Then, ASF driving is started. That is, by starting ASF driving after PF driving, a gap corresponding to the distance Lgap is secured between the preceding paper P1 fed by the PF driving and the succeeding paper P2 fed by the ASF driving. The Since the ASF drive is delayed and the acceleration starts, the gap between the preceding paper P1 and the succeeding paper P2 may be slightly changed during the transportation, for example, temporarily extending beyond the distance Lgap. As a result, the gap after completion of the conveyance becomes the distance Lgap.

  Thereafter, since the ASF drive and the PF drive carry the paper by the same transport distance, the paper feed of the preceding paper P1 and the paper feed of the subsequent paper P2 are a distance corresponding to a slight gap while the gap of the distance Lgap is secured. It is performed continuously only by separating Lgap. In FIG. 4, the interpage control position Ng is a position facing the head reference position H on the paper when the rear end of the paper (lower end in FIG. 4) is located at the interpage control position G in FIG. Yes, the position is a distance (La + Lb + Lc−Ld) from the rear end of the sheet in the sheet conveyance direction.

  FIG. 6 shows an acceleration / deceleration table that is referred to when the ASF motor and the PF motor are speed-controlled. The ROM 45 stores acceleration / deceleration table data that determines the speed profiles of the ASF motor 56 and the PF motor 58. FIG. 6 shows only the acceleration / deceleration table for the PF motor. The acceleration / deceleration table of this embodiment is prepared for each target speed. FIG. 6 shows an acceleration / deceleration table VT1 for the target speed V1 and an acceleration / deceleration table VT2 for the target speed V2 (where V1 <V2). Since the basic configurations of the tables are the same except that the target speeds are different, the acceleration / deceleration table VT1 will be described as an example here. The acceleration / deceleration table VT1 includes an acceleration table VTa1 for determining an acceleration profile and a deceleration table VTb1 for determining a deceleration profile, and is configured by a table indicating the correspondence between the distance D and the period T, respectively. Here, the period T is a pulse edge period of the encoders 61 and 62. The distance D and the period T are set in association with each other.

  The CPU 43 resets the ASF counter 66 and the PF counter 67 in advance prior to the start of driving of the ASF motor 56 and the PF motor 58 (paper conveyance start). For example, during paper feeding, the CPU 43 calculates the count value of the PF counter 67 that counts the edge of the pulse having a cycle inversely proportional to the motor rotation speed input from the encoder 62 from the motor rotation start position (paper transport start position). Obtained as distance D (motor drive amount). The CPU 43 controls the speed of the PF motor 58 by referring to the selected acceleration / deceleration table VT and instructing the motor driver 52 with a cycle T corresponding to the distance D.

  The CPU 43 also acquires the count value of the ASF counter 66 that counts the edges of the input pulses from the encoder 61 for the ASF motor 56 as the distance D from the motor rotation start position. Then, with reference to the selected acceleration / deceleration table VT, the ASF motor 56 is speed controlled by instructing the motor driver 51 with a cycle T corresponding to the distance D. Note that the edge period of the pulses acquired from the encoders 61 and 62 may be measured, and feedback control may be performed so that the measured detection period coincides with the target period T.

  The target speeds V1 and V2, which are constant speed regions, are determined from the shortest cycles T1 and T2 (target cycles) in the data group in the acceleration table. In FIG. 6, the two acceleration / deceleration tables VT1 and VT2 have the same values corresponding to the distance D and the period T, but actually, an appropriate acceleration / deceleration profile is obtained according to the target speeds V1 and V2. The numerical value is set. Although not shown, the acceleration / deceleration table for the ASF motor has basically the same configuration. The acceleration / deceleration table VT for the ASF motor is created so as to obtain an acceleration / deceleration profile in which priority is given to the ability to reliably feed the paper to the cueing position, whereas the acceleration / deceleration table for the PF motor is The acceleration / deceleration profile is created so that priority is given to the accuracy of the stop position of the paper during the paper feeding operation. Of course, the acceleration / deceleration profile can be appropriately changed according to the design concept.

  Based on the acceleration / deceleration tables VT1 and VT2, the target value (cycle T) corresponding to the distance D in the acceleration region / deceleration region is determined. Are output to the motor drivers 50 and 52. The motor drivers 50 and 52 respectively control the speeds of the corresponding ASF motor 56 and PF motor 58 according to the input target values. The motor drivers 50 and 52 control the voltages applied to the corresponding ASF motor 56 and PF motor 58, respectively, according to the input voltage command value. The value of the current flowing through the ASF motor 56 and the PF motor 58 is determined by this voltage, and a rotational torque corresponding to the current value is obtained. The voltage command value is determined for each distance D using a separate table or for each speed range obtained by dividing the acceleration / deceleration range into a plurality. A method for obtaining the deceleration start position, which is the starting point of the distance D in the deceleration table, will be described later.

  FIG. 7 shows a speed waveform of a speed profile obtained by speed control based on the acceleration / deceleration table. In this velocity waveform graph, the horizontal axis is the distance D and the vertical axis is the velocity V. In FIG. 7, the left graph corresponds to the acceleration / deceleration table VT1 in FIG. 6, and the right graph corresponds to the acceleration / deceleration table VT2 in FIG. Here, the speed V is a value corresponding to the reciprocal of the period T. Further, the paper transport distance (b1, c1 in the graph of FIG. 7) indicates specific numerical data of the transport distance given together with the paper feed command, paper feed command, and paper discharge command in the header of the print data. It is acquired from the transport distance parameter (for example, “Dy”). The two graphs shown in FIG. 7 are examples in which the transport distance Dy is Dy = b1 and Dy = c1.

  As shown in FIG. 7, the speed waveform based on the acceleration / deceleration table VT draws a substantially trapezoidal shape, and the height of the trapezoidal waveform is proportional to the target speed. Then, as the height of the trapezoidal waveform increases, the travel distance Da required for acceleration (Da1, Da2 in each graph of FIG. 7) and the travel distance Db required for deceleration (Db1, each graph of FIG. 7). Db2) tends to be long. Therefore, in order to reach the target speed Vc (V1, V2 in the graph of FIG. 7) (or target period Tc), the target speed Vc (or target period Tc) is reached from the acceleration start point (distance D = 0). The sum (Da + Db) of the moving distance Da in the acceleration process until the stop and the moving distance Db in the deceleration process from the target speed Vc (or the target period Tc) to the stop is required as the minimum distance. Therefore, when the transport distance Dy (= b1, c1) is determined, the condition of the acceleration / deceleration table VT that can be employed is that the transport distance Dy is equal to or greater than the minimum distance (Da + Db).

  The CPU 43 executes a paper feed sequence when receiving a paper feed command from the header of the print data, executes a paper feed sequence when receiving a paper feed command, and executes a paper discharge sequence when receiving a paper discharge command. When acquiring a paper feed / paper feed / discharge command from the header, the CPU 43 acquires a target speed and a transport distance Dy as parameters for instructing specific execution contents when executing the command together with the command. The target speed indicated by the command parameter (hereinafter referred to as the first target speed) is a value set in accordance with, for example, each paper feed / paper feed / discharge and the print mode. Examples of the print mode include a high-speed print mode that prioritizes the print speed over the print image quality, and an image quality priority mode that prioritizes the print image quality over the print speed.

  Selection of the acceleration / deceleration table VT is performed as follows. First, the acceleration / deceleration table VT having the first target speed given as the command parameter as the target speed is checked, the minimum distance (Da + Db) is compared with the current transport distance Dy, and “Dy” is the minimum distance (Da + Db). If it is above, the acceleration / deceleration table VT for the first target speed is adopted as it is. On the other hand, when “Dy” is less than the minimum distance (Da + Db), the acceleration / deceleration table for the first target speed cannot be adopted because of the minimum distance, and the transport distance Dy is equal to or greater than the minimum distance (Da + Db). Of the other acceleration / deceleration tables that satisfy the condition, the one with the fastest target speed (second target speed) is selected.

  When the transport distance Dy and the acceleration / deceleration table VT are determined, the CPU 43 starts motor speed control. For example, the speed control of the PF motor 58 will be described as an example with reference to the acceleration / deceleration table VT1 of the target speed V1 shown on the left side in FIG. 6 and the graph shown on the left side in FIG. The CPU 43 first resets the PF counter 67 and then refers to the acceleration table VTa1 in the selected acceleration / deceleration table VT1, and sequentially instructs the motor driver 52 to specify a cycle T corresponding to the distance D, which is a count value of the PF counter 67. Then, the PF motor 58 is accelerated. When the distance T reaches Da1 and the commanded cycle T reaches the target cycle T1, the acceleration is terminated, and in the subsequent constant speed range, the target cycle T1 is continuously commanded as it is. When the deceleration start position (distance “Dy−Db1”) is reached, the PF motor 58 is decelerated by sequentially instructing the period T corresponding to the distance D from the deceleration start position with reference to the deceleration table VTb1.

  By the way, the conveyance speed of the paper feed roller 22 is determined by the rotational speed of the ASF motor 56, the reduction ratio of the train wheel between the ASF motor 56 and the paper feed roller 22, the outer diameter of the paper feed roller 22, and the like. Further, the transport speed of the paper feed roller 29 is determined by the rotational speed of the PF motor 58, the reduction ratio of the train wheel between the PF motor 58 and the transport drive roller 29a, the outer diameter of the transport drive roller 29a, and the like. In the present embodiment, if the rotational speed of the ASF motor 56 and the rotational speed of the PF motor 58 are the same speed, the both wheels are set so that the transport speed of the paper feed roller 22 and the transport speed of the paper feed roller 29 are the same speed. It is assumed that values such as the reduction ratio of each row and each roller diameter are set. For this reason, the speed V in the graph of FIG. 7 and further in the graphs of FIG. 8 and FIG. 9 indicates the sheet conveyance speed at the time of ASF drive and PF drive, but the ASF motor has the same conversion ratio to the conveyance speed. 56 and the rotational speeds of the PF motor 58 are also shown.

Next, the sheet conveyance processing routine shown in the flowchart of FIG. 10 executed by the CPU 43 will be described with reference to the graphs of FIGS.
In step S10, a paper feeding operation is performed. That is, the paper P is fed by driving the ASF motor 56 and the PF motor 58 in a state where the hopper 15 and the retard roller 24 are arranged at the paper feeding position shown in FIG. The paper P1 is cued by this paper feeding operation. At this time, the paper feed amount counter 65 uses the position when the leading edge of the paper P1 coincides with the head reference position H (see FIG. 3) as the origin, and the count value corresponding to the paper feed amount conveyed from this origin is counted. Has been.

  In the next step S20, a printing operation is performed. That is, printing for one pass is performed by driving the carriage motor 55 to move the carriage 18 in the main scanning direction X and ejecting ink from the nozzles of the recording head 19 at the printing position during the movement.

  In step S30, if the current paper feed is performed, it is determined whether or not the inter-page control position Ng is exceeded. Specifically, it is determined whether or not the value obtained by adding the transport distance Dy to the current count value Nx of the paper feed amount counter 65 exceeds the interpage control position Ng. If the inter-page control position Ng is exceeded, the process proceeds to step S50. If the inter-page control position Ng is not exceeded, the process proceeds to step S40. When the current position Nx of the preceding paper P1 coincides with the inter-page control position Ng, a value (Nx + Dy) obtained by adding the transport distance Dy to the count value Nx is larger than the inter-page control position Ng, and the inter-page Since the paper feed exceeds the control position Ng for the first time, it is determined that the inter-page control position Ng is also exceeded in this case.

In step S40, a paper feeding operation is performed. That is, the ASF motor 56 and the PF motor 58 are driven according to the instruction of the paper feed command to feed the paper by the transport distance Dy.
On the other hand, if it is determined in step S30 that the current paper feed exceeds the inter-page control position Ng, the following steps S50 and S60 are executed to open a specified gap Lgap between the preceding paper and the succeeding paper. Processing will be performed.

  In step S50, the paper feeding operation is performed up to the interpage control position. That is, if it is determined in step S30 that the current paper feed exceeds the interpage control position Ng, the current paper feed operation is performed to transport the paper from the paper feed start position (current position Nx) to the interpage control position Ng. The first paper feeding operation and the second paper feeding operation for transporting paper from the interpage control position Ng to the paper feeding end position (Nx + Dy) are divided into two times. Of these steps, the first paper feeding operation is performed in this step. In the first paper feeding operation, the ASF motor 56 and the PF motor 58 are driven at the same speed and the same distance. That is, the paper is transported by the same distance at the same transport speed by the paper feed roller 22 and the paper feed roller 29.

  At this time, the conveyance distance of the first paper feeding operation is determined as “Ng−Nx”. When the transport distance (Ng−Nx) is equal to or greater than the minimum distance (Da + Db) of the acceleration / deceleration table VT for the first target speed, the acceleration / deceleration table VT for the first target speed is adopted. When the minimum distance condition is not satisfied, the one having the highest target speed among the other acceleration / deceleration tables VT in which the transport distance (Ng−Nx) is equal to or greater than the minimum distance (Da + Db) is selected. This acceleration / deceleration table VT selection process is performed for each of the ASF motor 56 and the PF motor 58, and the acceleration / deceleration table VT employed by each is selected. If the target speeds of the selected acceleration / deceleration tables VT are different, the acceleration / deceleration table VT for the target speed on the high speed side is changed to the acceleration / deceleration table VT for the target speed on the low speed side in accordance with the target speed on the low speed side. . Thus, the acceleration / deceleration table VT having the same target speed for the ASF motor 56 and the PF motor 58 is determined.

  Of course, the gear train between the ASF motor 56 and the paper feed roller 22 and the gear train between the PF motor 58 and the paper feed roller 29 have different reduction ratios, and the rotational speed of the ASF motor 56 and the conveyance of the paper feed roller 22 are different. When the ratio of the speed and the ratio of the rotation speed of the PF motor 58 and the transport speed of the paper feed roller 29 are different, the ASF is set so that the transport speeds of the paper feed roller 22 and the paper feed roller 29 are the same. Each acceleration / deceleration table VT for the motor 56 and the PF motor 58 is determined. If the current position Nx of the preceding paper P1 coincides with the inter-page control position Ng, the first paper feed operation in step S50 is not performed because the transport speed of the first paper feed operation is “0”. Only the second paper feeding operation in step S60 is performed.

  In step S60, the paper feeding operation is performed up to the printing position. That is, the second paper feeding operation is performed. In this paper feeding operation, the driving of the PF motor 58 is started first, and after the PF motor 58 is driven by the interpage control distance Lgap, the driving of the ASF motor 56 is started. The drive start timing of the ASF motor 56 is determined when the count value of the PF counter 67 reset at the start of the drive of the PF motor 58 has reached the value of the interpage control distance Lgap. As described above, in the present embodiment, the PF counter that is a position parameter for measuring the drive position of the PF motor 58 that has been driven first out of the two motors of the ASF motor 56 and the PF motor 58 that are the drive sources for paper conveyance. When the count value 67 reaches a predetermined value (standby end position), control is performed to permit driving of the other ASF motor 56 that has been on standby. By this motor control, a specified gap Lgap is secured between the preceding sheet and the succeeding sheet.

In the next step S70, a printing operation is performed. This printing operation is the same processing as step S20.
In step S80, it is determined whether printing is complete. If a paper discharge command is received in the print data, it is determined that printing is complete. If printing is completed, the process proceeds to step S90, and if printing is not completed, the process returns to step S30. That is, the processes in S30 to S80 are repeated until it is determined in step S80 that printing is completed. When the paper feed operation (S40) and the print operation (S70) are alternately performed and it is determined that the count value Nx of the paper feed amount counter 65 exceeds the interpage control position Ng when the paper feed is performed, the interpage control ( S50 and S60) are performed. If it is determined in S80 that printing is complete, the process proceeds to step S90.

  In step S90, it is determined whether the print completion position exceeds the interpage control position. Here, the print completion position indicates the count value Nx of the current paper feed amount counter 65 that has received the paper discharge command. If the print completion position exceeds the interpage control position Ng, the process proceeds to step S100. If the print completion position does not exceed the interpage control position Ng, the process proceeds to step S110.

  In step S100, the paper feeding operation is performed until the leading edge of the paper is detected. That is, in this paper feeding operation, the PF motor 58 and the ASF motor 56 are simultaneously driven at the same distance until the leading edge of the succeeding paper is detected by the paper detection sensor 33.

  On the other hand, if it is determined in step S90 that the print completion position does not exceed the interpage control position Ng, the following steps S110 and S120 are executed to open a specified gap Lgap between the preceding sheet and the succeeding sheet. Processing will be performed.

  In step S110, the paper discharge operation is performed up to the interpage control position. That is, if it is determined in step S90 that the inter-page control position Ng has not been exceeded, it is necessary to perform inter-page control that opens a specified gap with the succeeding paper while the paper is being discharged. Therefore, first, the paper P1 is discharged to the interpage control position shown in FIG. 3 where the count value of the paper feed amount counter 65 is Ng.

  In the next step S120, the paper feeding operation is performed until the leading edge of the paper is detected. That is, after the preceding sheet is discharged to the inter-page control position Ng, a sheet feeding operation for feeding the succeeding sheet to a position where the leading edge of the succeeding sheet is detected by the sheet detection sensor 33 is performed. In this paper feeding operation, the PF motor 58 has a paper leading edge detection distance (Lc−Ld) that is a distance necessary for transporting the subsequent paper from the position shown in FIG. 3 to the position detected by the paper detection sensor 33. Driving is performed by a distance (Lc−Ld + Lgap) including the interpage control distance Lgap. On the other hand, after the PF motor 58 is driven by the interpage control distance Lgap, the ASF motor 56 is driven by the leading edge detection distance (Lc−Ld). .

  When the paper transport control processing program is completed in this way, the succeeding sheet is fed to a position where the leading edge of the succeeding sheet is detected by the sheet detecting sensor 33, and a predetermined gap Lgap is opened from the leading end of the succeeding sheet. The preceding paper is discharged so that the end is located. Thereafter, the program is executed again to start the cueing of the subsequent sheet.

  In the processes of steps S50 and 110, the process of transporting the preceding paper P1 to the interpage control position Ng by both the ASF drive and the PF drive corresponds to the transport step, and the process of stopping the ASF drive is the feeding stop step. It corresponds to. In steps S60 and S120, the process of resuming the ASF drive after waiting for the interval between the sheets P1 and P2 to reach the inter-page control distance Lgap corresponds to the feed resuming step. Further, in steps S50 and S110, the process of temporarily stopping the PF drive when the preceding sheet P1 reaches the interpage control position Ng corresponds to the conveyance stop step.

Next, the operation of the printer 11 that performs the paper conveyance process with interpage control will be described.
There are three cases in which the inter-page control position Ng passes when printing is performed on a sheet. One is to set the inter-page control position Ng at the time of paper feeding in the middle of printing in which the paper feeding operation at the minimum feeding pitch and the one-pass printing operation are alternately performed, for example, when printing is performed on substantially the entire surface of the paper. It is a case of passing. In this case, the paper feed amount is divided into two, the preceding paper is transported by two paper feed operations, and the subsequent paper is only fed the first time. Thereafter, the preceding paper is fed by the minimum feed pitch alternately with the printing operation, but the driving of the ASF motor 56 is not permitted until the count value of the paper feed amount counter 65 reaches the value (Ng + Lgap). When a predetermined distance Lgap is opened between the preceding sheet and the succeeding sheet, the driving of the ASF motor 56 is permitted, and both the ASF motor 56 and the PF motor 58 are driven by the same distance when the sheet is fed.

  Second, as shown in FIG. 4, a blank area BA exists between the two print areas PA1 and PA2, and the transport distance “from the position where printing of the print area PA1 is completed to the print start position of the print area PA2” This is a case in which the inter-page control position Ng is passed during the paper feeding of “a”. In this case, it is determined that when the paper is transported by the transport distance “a”, it passes through the interpage control position Ng (YES in S30). That is, it is determined that the paper feed amount count value (Nx + a) obtained by adding the transport distance a to the current count value Nx of the paper feed amount counter 65 exceeds the interpage control position Ng (Nx + a> Ng). The paper feed of the conveyance distance a is divided into two PF drivings of the conveyance distance b1 and the conveyance distance c1, and is divided into two ASF drivings of the conveyance distance b2 and the conveyance distance c2. First, PF driving of the transport distance b1 and ASF driving of the transport distance b2 (= b1) are performed substantially simultaneously, and the paper is transported to the interpage control position Ng. Next, after the PF driving of the transport distance c1 is performed, when the preceding sheet is driven by the distance Lgap, the ASF driving is permitted and the ASF driving of the transport distance c2 is started. As a result, a gap corresponding to the distance Lgap is secured between the preceding sheet and the succeeding sheet.

  The third is the case where printing is performed only in the area near the leading edge of the paper P1 and passes through the inter-page control position Ng during the paper discharge after the printing is completed. When the printing is completed, the preceding paper P1 is nipped by the paper feed roller 22. In this case, the paper discharge operation by ASF driving and PF driving of the transport distance (Psize−La−Lb−Lc−Nx) required until the preceding paper reaches the inter-page control position Ng is performed, and further, the preceding paper is printed on the page. ASF driving of the transport distance (Lc−Ld) necessary for transporting the subsequent sheet from the position reaching the intermediate control position Ng to the position detected by the paper detection sensor 33, and the PF of the transport distance (Lc−Ld + Lgap) The paper feeding operation by driving is performed. In the latter paper feeding operation, the ASF driving is permitted after the PF driving is driven by a predetermined gap Lgap.

  In the present embodiment, in any of the above three cases, when transporting paper that passes through the interpage control position Ng, paper transport to the interpage control position Ng and the PF drive interpage control distance Lgap performed thereafter. A gap corresponding to the distance Lgap is secured by allowing ASF driving after a minute drive. Of these three cases, in the case of paper feeding over the second blank area BA and in the case of the third paper discharge operation, the initial transport distance before the division into two times becomes relatively long. In this case, the transport distance b1 of the previous round and the transport distance c1 of the back round are usually different depending on the position where one transport drive is divided. When one transport drive is divided into two transport drives, the transport distance of the divided two transports is shortened. Therefore, the transport speed of the transport operation with a short transport distance is reduced in relation to the minimum distance. Cases that differ from the transport speed of long transport operations occur.

  However, since the ASF drive waits for the start of paper feeding in order to open the gap distance Lgap, it is necessary to temporarily stop the ASF drive. However, the PF drive is performed once without stopping temporarily during the PF drive. If the configuration is such that the paper feed operation and the paper discharge operation are performed by driving, it is efficient in terms of throughput. However, if the PF drive is not stopped, if the transport speed of the previous round is different from that of the subsequent round, it is necessary to shift the speed halfway, and a dedicated acceleration / deceleration table that can handle the shift must be prepared separately. I must. For this reason, in the present embodiment, a configuration is adopted in which the PF drive is temporarily stopped halfway.

  8 and 9 show graphs for explaining interpage control. FIG. 8 shows a case where the transport distances are different in the two transport drives divided at the interpage control position Ng, and is an example in which the transport distance of the subsequent round is longer than the transport distance of the previous round. FIG. 9 shows a case where the transport distances are the same in two transport drives divided at the interpage control position Ng. Both graphs are shown by examples of paper feeding across the blank area BA shown in FIG. In each figure, the upper graph shows ASF driving, and the lower graph shows PF driving. In each graph, the horizontal axis is the distance D, and the vertical axis is the speed V (reciprocal of the period T).

  First, referring to the graph of FIG. 8, when the transport distance a is divided into two at the inter-page control position Ng, the inter-page control when the rear transport distance c1 is longer than the previous transport distance b1 will be described. To do. Although the PF drive can transport the transport distance a at a time, the transport to the inter-page control position Ng where the preceding paper is nipped by both the paper feed roller 22 and the paper feed roller 29 is the ASF drive. It is necessary to make the PF drive the same speed. This is to prevent excessive tension or slack from being applied to the portion between the preceding paper nipped by the paper feed roller 22 and the paper feed roller 29. On the other hand, as the acceleration / deceleration table VT driven by ASF, the acceleration / deceleration table VT having the shortest distance less than the conveyance distance b2 is selected with the fastest target speed. The acceleration / deceleration table VT1 in which the speed V1 is set is selected. For this reason, if the transport distance a is to be transported by a single PF drive, it is necessary to PF drive the entire transport distance a at the low target speed V1 in accordance with the ASF drive of the transport distance b2. In this case, since the long transport distance a is PF-driven at a low speed, the throughput is reduced. This decrease in throughput becomes more noticeable as the transport distance a is longer. On the other hand, a configuration in which the speed is changed from the speed V1 to the speed V2 after the interpage control position Ng is considered is also conceivable, but in this case, an acceleration / deceleration table for shifting is required.

  Therefore, in the present embodiment, the PF drive is temporarily stopped when the ASF drive is temporarily stopped at the interpage control position Ng. That is, as shown in the graph of FIG. 8, until the inter-page control position Ng is reached, the transport distance b2 is ASF driven at the speed V1, and the transport distance b1 (= b2) is PF driven at the speed V1. That is, the ASF motor 56 and the PF motor 58 are driven at the same speed V1 by the same distance b2 (= b1). Then, after the drive of the PF motor 58 is temporarily stopped, the drive is immediately resumed to drive the transport distance c1. At this time, since the transport distance c1 is sufficiently longer than the transport distance b1, the acceleration / deceleration table VT2 set with a higher target speed V2 (> V1) is selected and transported at the speed V2. In this case, as the transport distance c1 is longer than the transport distance b1, it is easier to suppress a decrease in throughput.

  Next, as shown in the graph of FIG. 9, when the transport distance b1 is equal to the transport distance b2, the speeds of the PF motors 58 when transporting the transport distances b1 and c2 are both equal to the speed V3. In this embodiment, even when driving at the same speed V3 before and after the interpage control position Ng is sandwiched, the driving of the PF motor 58 is temporarily stopped when the driving of the ASF motor 56 is stopped. This is a configuration in which the PF motor 58 is temporarily stopped when the driving of the ASF motor 56 is stopped at the inter-page control position Ng so that it is not necessary to add a determination process for determining whether to stop or not. It is said.

As described above in detail, according to the first embodiment, the following effects can be obtained.
(1) In the case of paper conveyance passing through the inter-page control position Ng, the ASF motor 56 and the PF motor 58 are driven at the same speed up to the inter-page control position Ng, and the remaining conveyance distance from the inter-page control position Ng is set. When transporting, a configuration is adopted in which the driving start of the ASF motor 56 is permitted after the PF motor 58 is driven by a distance Lgap corresponding to the gap. Even if the preceding sheet and the succeeding sheet are continuously fed, a specified gap can be secured between the preceding sheet and the succeeding sheet. Therefore, the leading edge of the succeeding paper can be reliably detected by the paper detection sensor 33.

  (2) In the configuration in which the conveyance speed depends on the conveyance distance, the driving of the PF motor 58 is also temporarily stopped when the ASF motor 56 stops at the interpage control position Ng. Therefore, when the remaining transport distance from the interpage control position Ng is longer than the transport distance to the interpage control position Ng, the second driving speed of the PF motor 58 is higher than the first driving speed V1 of the PF motor 58. V2 can be set at high speed, and a decrease in throughput can be suppressed.

  (3) Due to the minimum distance of the acceleration / deceleration table VT, when the transport distance is short, the driving speed of the ASF motor 56 must be kept low, and the driving speed of the PF motor 58 is set to the driving speed of the ASF motor 56. Even when the speed must be adjusted to a low speed, after passing the inter-page control position Ng, the transport speed for transporting the remaining transport distance c1 is switched to a higher speed than the transport speed for transporting the transport distance b1. It is possible.

  (4) When the ASF motor 56 stops at the interpage control position Ng, the driving of the PF motor 58 is temporarily stopped. Therefore, it is possible to switch to a higher transport speed after passing the interpage control position Ng using the acceleration / deceleration table VT originally provided without adding an acceleration / deceleration table for shifting.

  (5) When the ASF motor 56 stops at the interpage control position Ng, the driving of the PF motor 58 is temporarily stopped uniformly. Therefore, it is not necessary to add a determination process for determining whether or not to stop the driving of the PF motor 58, so that the control content can be simplified.

(Second Embodiment)
Next, the paper interval forming process in the second embodiment will be described with reference to FIGS. In the second embodiment, the ASF drive speed is changed at a higher speed from the position after the interpage control position Ng without temporarily stopping the PF drive when the ASF drive is stopped. Since the configuration and electrical configuration of the printer 11 are the same as those in the first embodiment, the description of the configuration common to the first embodiment will be omitted, and particularly different inter-page control will be described in detail.

  The CPU 43 performs the paper conveyance control process shown in FIG. 10 described in the first embodiment. In this paper conveyance control process, when performing the inter-page control in the case of YES in the determination process in step S30 and in the case of NO in the determination process in step S90, steps S50, S60 and steps in the first embodiment are performed. Instead of the processes of S110 and S120, the inter-page control process shown in FIG. 14 is executed. In the flowchart shown in FIG. 14, the driving of the PF motor 58 when the paper is transported by the transport distances b1 and c1 is expressed as “PF drive b1” and “PF drive c1”, respectively, and only the transport distances b2 and c2 are used. The driving of the ASF motor 56 when transporting the paper is expressed as “ASF driving b2” and “ASF driving c2”, respectively. Further, the driving amount of the ASF motor 56 necessary for transporting the paper by the transport distances b2 and c2 is expressed as ASF driving amounts b2 and c2, and the PF motor necessary for transporting the paper by the transport distances b1 and c1. The driving amount 58 is expressed as PF driving amounts b1 and c1.

  FIG. 11 is a graph showing a speed waveform when performing interpage control. In the drawing, the upper stage shows ASF driving, and the lower stage shows PF driving. In the first embodiment, when the ASF drive is stopped at the interpage control position Ng, the PF drive is also temporarily stopped (see the graph of FIG. 8). In the second embodiment, the lower graph in FIG. As shown, for the PF drive, when the ASF drive is stopped at the interpage control position Ng, it is not temporarily stopped, but at a predetermined timing after the interpage control position Ng, from the constant speed V1 to the speed V2. Accelerating. However, the acceleration / deceleration table VT dedicated to shifting is not added, and the acceleration / deceleration table VT shown in FIG. 6 is used as in the first embodiment.

  First, the CPU 43 obtains the current paper transport distance (paper feed amount or paper discharge amount, paper feed amount) from the header of the print data. A value (Nx + a) obtained by adding the current transport distance a (PF drive amount) to the count value Nx (<Ng) of the current paper feed amount counter 65 exceeds the inter-page control position Ng ((Nx + a)> Ng). In this case, the CPU 43 determines that interpage control should be performed. The CPU 43 that has made this determination divides the PF drive amount a into two parts, a PF drive amount b1 and a PF drive amount c1 (where a = b1 + c1). Here, the PF drive amount b1 is a distance from the current position Nx before the current paper feed to the interpage control position Ng. The PF drive amount c1 is a distance from the interpage control position Ng to the conveyance end position (Nx + a).

  Further, the CPU 43 has an ASF drive amount b2 that can feed from the current position to the interpage control position, and an ASF drive amount c2 that can be transported to the transport end position when the PF motor 58 is driven after being driven by Lgap. And calculate. Thus, the PF drive amounts b1 and c1 and the ASF drive amounts b2 and c2 are determined.

  First, in step S210, a driveable speed (target speed) is selected from the PF drive amount b1 and the ASF drive amount b2. The CPU 43 first individually obtains target speeds respectively corresponding to the PF drive amount b1 and the ASF drive amount b2. When the CPU 43 accepts the conveyance instruction, the target speed is instructed together. The acceleration / deceleration table is prepared separately for PF drive and ASF drive. This is because, in PF driving, priority is given to the stop position accuracy after paper feeding, whereas in ASF driving, priority is given to being able to move reliably to the target position, and appropriate speed profiles are different for both.

  First, an acceleration / deceleration table corresponding to the instructed target speed is acquired. If the PF drive amount b1 is equal to or greater than the minimum distance of this acceleration / deceleration table, this acceleration / deceleration table is adopted. On the other hand, if the PF drive amount b1 is less than the minimum distance of the acceleration / deceleration table, another acceleration / deceleration table candidate in which the PF drive amount b1 is equal to or greater than the minimum distance is searched for, and the acceleration / deceleration that can obtain the fastest target speed is obtained. Select a table. In the same manner, an appropriate one of the ASF driving amount b2 is selected from the acceleration / deceleration table for ASF driving.

  Thus, the acceleration / deceleration table for PF driving and the acceleration / deceleration table for ASF driving are determined from the respective drive amounts b1 and b2. By the way, when the paper P1 is nipped between the paper feed roller 22 and the retard roller 24, the paper feed roller 22 and the paper feed roller 29 need to transport the paper P1 at the same speed. Therefore, if the target speed differs between the acceleration / deceleration table for PF driving and the acceleration / deceleration table for ASF driving determined from the respective driving amounts b1, b2 (conveyance distance), the target speed should be adjusted to the lower target speed. The acceleration / deceleration table is changed. Thus, the target speed is determined by determining the acceleration / deceleration table for PF driving and the acceleration / deceleration table for ASF driving. That is, the target speed, that is, the acceleration / deceleration table is determined so that the first transport speed that is the paper transport speed is the same between the ASF drive and the PF drive. For example, the acceleration / deceleration table VT1 with the target speed V1 shown in FIG. 6 is selected.

  In step S220, a driveable speed (target speed) is selected from the PF drive amount c1 and the ASF drive amount b2. By the way, after the preceding paper P1 has passed the inter-page control position, the preceding paper P1 is released from the nip by the paper feed roller 22, so that the PF motor 58 and the ASF motor 56 are driven at different transport speeds. Can do. Therefore, in the paper conveyance process after passing the inter-page control position, an acceleration / deceleration table that satisfies the minimum distance condition is determined from the driving amounts c1 and c2, and the target speed is determined by determining each acceleration / deceleration table. For example, the acceleration / deceleration table VT2 with the target speed V2 shown in FIG. 6 is selected.

In step S230, a PF drive amount a (= b1 + c1) is set.
In step S240, the start timing of the ASF drive c2 is set. That is, after the PF drive b1 (or ASF drive b2), the end point of the PF drive for the distance Lgap is the start timing of the ASF drive c2, so “b1 + Lgap” is set as the count value converted value of the PF counter 67.

  In step S250, a search / setting process for the acceleration start timing of the PF drive c1 is performed. That is, first, the constant speed cycle (the value of the target speed cycle T) “T1” in the acceleration / deceleration table VT1 (or acceleration table VTa1) of the target speed V1 referred to during the PF drive b1 (see FIGS. 6 and 3). To get. Next, with reference to the acceleration / deceleration table VT2 (or acceleration table VTa2) of the PF drive amount c1, data of the distance D necessary until the same cycle T1 as the previous constant speed cycle “T1” is acquired. In the example of FIG. 13, since the distance D at the cycle “T1” in the acceleration table VTa2 is “D1”, data “D1” of the distance required from the stop state to the speed of the cycle “T1” is obtained. The position where the sheet P1 has finished moving the distance of the PF drive amount b1 is the interpage control position Ng. Therefore, when the paper P1 reaches the interpage control position Ng, the preceding paper P1 is released from the nip of the paper feed roller 22, so there is no problem even if the PF motor 58 is shifted. Therefore, the shift may be started at the timing when the position where the movement of the PF drive amount b1 is finished is reached. However, in this example, the acceleration table VTa2 is only referred to (the cycle is not commanded) on the assumption that acceleration is started from zero speed according to the acceleration / deceleration table VT2 at the timing at which the movement of the PF drive amount b1 is completed. The acceleration / deceleration table VT1 is switched to the acceleration / deceleration table VT2 at the timing when the cycle T (speed) determined by reference reaches the constant speed cycle T1 (target speed V1) of the acceleration / deceleration table VT1. Then, by switching between the acceleration / deceleration tables VT1 and VT2, two speed profile waveforms based on the two acceleration / deceleration tables VT1 and VT2 are combined, and shift control for shifting from the target speed V1 to the target speed V2 is performed. Realized.

  In step S260, the reference start position of the PF drive amount c1 is set. That is, since it corresponds to the start point (acceleration table reference start position E) for starting the counting of the distance data D1 acquired in the previous step S250, in this example, the PF drive amount b1 until the interpage control position is reached. As the acceleration table reference start position E, “b1” is set as the count value converted value of the PF counter 67. The preparation of necessary data setting is completed by the processing of steps S210 to S260 described above.

In the next step S270, driving of the ASF motor 56 is started, and driving of the ASF driving amount b2 is started.
In step S280, the driving of the PF motor 58 is started and the driving of the PF driving amount a is started.

  In step S290, it is determined whether or not the driving distance Npf of the PF counter 67 has reached the acceleration table reference start position E (Npf ≧ b1). In this example, since the acceleration table reference start position E is set to the position when the sheet reaches the interpage control position, the acceleration is accelerated when the driving distance Npf counted by the PF counter 67 reaches the PF driving amount b1. It is determined that the table reference start position E has been reached. If the acceleration table reference start position E has been reached, the process proceeds to the next step S300, and if the acceleration table reference start position E has not been reached, the process waits until it reaches.

  In step S300, parameters of the acceleration / deceleration table VT2 for the PF drive amount c1 are set. That is, the distance and cycle data in the acceleration table VTa2 are set as parameters so that the acceleration table VTa2 to be used next can be referred to instead of the acceleration table VTa1 referred to so far.

  In step S310, it is determined whether or not the driving distance Npf has reached the acceleration start timing position F. When the driving distance Npf counted by the PF counter 67 reaches the value (b1 + D1) corresponding to the acceleration start timing position F, the process proceeds to step S320, and when the driving distance Npf does not reach the value corresponding to the acceleration start timing position F, the process waits. To do. During this standby, the CPU 43 refers to the acceleration table VTa2 from the acceleration table reference start position E, but counts with reference to the distance P until the distance P from the acceleration table reference start position E reaches “D1”. Only the period T corresponding to the distance P is not commanded.

  In step S320, the acceleration table VTa2 with the PF drive amount c1 is applied. At this time, the distance “D1” corresponding to the same period “T1” as the constant speed period “T1” is applied as the reference start position. Then, the CPU 43 switches the acceleration table to be referenced from the acceleration table VTa1 to the acceleration table VTa2, and starts speed control according to the acceleration table VTa2 from the reference start position D1.

  In the next step S330, it is determined whether or not the driving distance Npf of the PF counter 67 has reached the start timing for starting the feeding of the ASF driving amount c2. That is, it is determined whether or not the distance of Lgap has been moved after the PF drive amount reaches “b1”. Specifically, it is determined whether or not the driving distance Npf counted by the PF counter 67 has reached “b1 + Lgap”. Of course, after “b2” is counted by the ASF counter 66, it may be determined whether or not the PF counter 67 has further counted the value of “Lgap”. When the PF drive amount reaches “b1”, the distance of Lgap is moved to satisfy Npf ≧ b1 + Lgap. When the distance of Lgap is not moved, the process proceeds to step S340.

In step S340, ASF drive c2 is started. Thus, after the ASF drive is stopped, the ASF drive is resumed after waiting for the PF drive for the distance Lgap.
In the above example, the magnitude relationship between the PF drive amount b1 obtained by dividing the PF drive amount a into two and the PF drive amount c1 is b1 <c1, but conversely, as shown in FIG. , B1> c1, the ASF drive stops after the ASF drive amount b2 is driven, and then the APF drive amount c2 starts to be accelerated after the PF drive amount is driven by the inter-page control distance Lgap. In this case, the PF drive speed is not decelerated halfway so as to have two constant speed regions, but the acceleration / deceleration table determined from the PF drive amount a (however, the acceleration / deceleration table determined from the ASF drive amount b2 and the target speed are It is driven according to an acceleration / deceleration table determined to match. For this reason, it is possible to prevent a delay when the paper P1 reaches the next recording position.

  In the second embodiment, in steps S50 and S110 in FIG. 10, the process of transporting the preceding paper P1 to the interpage control position Ng by both the ASF drive and the PF drive and stopping the ASF drive is performed by feeding. This corresponds to the step of stopping or decelerating the unit (however, in the present embodiment, the example of stopping). In steps S60 and S120, the ASF driving is performed after waiting for the interval between the sheets P1 and P2 to reach the interpage control distance Lgap. The process of starting the acceleration corresponds to the control step. And in FIG. 14, each process of step S240-S320 mainly corresponds to the speed change step.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(6) In addition, while the paper is sandwiched between the paper feed roller 22 and the retard roller 24, the ASF motor 56 and the PF motor are driven so that the paper feed roller 22 and the paper feed roller 29 are rotated at the same speed. 58 needs to be driven. In the case of transport across the inter-page control position, the acceleration / deceleration table set to the minimum distance not more than the transport distance to the inter-page control position is selected for each ASF and PF. Set to the lower of the target speeds. Therefore, when the inter-page control position that divides the range from the transport start position to the transport end position (paper feed position or paper feed position) is much longer than the first transport distance, Even when a high target speed can be set at the paper feed speed after the control position, if the paper feed is continued to the transport end position (paper feed position or paper feed position) without being stopped halfway, the second transport distance c1 is Despite being long, paper must be fed at a low speed that matches the paper feed speed determined from the first transport distance b1. However, in this embodiment, when the sheet reaches the interpage control position and the ASF motor 56 is temporarily stopped, the PF motor 58 is accelerated by a speed change, so compared with the first embodiment in which the PF motor 58 is temporarily stopped. Paper can be fed at higher speed. When the second transport distance c1 is longer than the first transport distance b1, the preceding paper P1 can be transported at the second transport speed V2 that is higher than the first transport speed V1, and therefore the preceding paper P1 and the subsequent paper P2 In addition, a gap Lgap that is greater than the specified value can be ensured between and the printing throughput can be improved.

  (7) In the case of a transport operation straddling the interpage control position Ng, the subsequent paper P2 that has been fed and stopped to the interpage control position Ng waits until a gap Lgap that is greater than or equal to a predetermined amount is secured between the preceding paper P1. In some cases, the driving of the PF motor 58 is accelerated without stopping. Therefore, an acceleration / deceleration table having only one constant speed (target speed) can be used, and an acceleration capable of speed change with a plurality of target speeds (constant speeds) of the first transport speed and the second transport speed. It is not necessary to adopt a configuration in which a deceleration table is added separately. When such an acceleration / deceleration table capable of shifting is adopted, a very large number of combinations of acceleration / deceleration tables must be added for each of a plurality of target speeds, but this is not necessary. Therefore, there is no need to increase the storage capacity of the memory or increase the memory.

  (8) When the first transport distance b1> the second transport distance c1, the first transport speed V1, which is each target speed of the acceleration / deceleration table determined from the transport distance, is lower than the second transport speed V2. The conveyance was performed at the first conveyance speed V1 without decelerating the conveyance speed in the middle (that is, without decelerating to the second conveyance speed). Therefore, paper feeding can be performed at a higher speed than the configuration in which the speed is reduced in the middle.

It should be noted that the present invention is not limited to the above embodiments, and the following forms can also be adopted.
(Modification 1) In the second embodiment, the position where the driving of the PF drive amount b1 is completed, that is, the interpage control position Ng is set as the acceleration table reference start position, but the present invention is not limited to this. In short, it is sufficient that the acceleration table reference start position E is a position where the paper is released from the nip by the paper feed roller 22 when the acceleration start timing position F is reached. For example, the position before reaching the interpage control position Ng is set as the acceleration table reference start position, and acceleration is started from the acceleration start timing position obtained by counting the distance D1 from the acceleration table reference start position. The timing when the sheet is conveyed and released from the nip by the sheet feeding roller 22 is sufficient. For example, as shown in FIG. 15, the distance D1 at the constant speed period T1 from the acceleration table VTa2 is moved from the reference start position by a distance D1 with “b1-D1” subtracted from b1 as the reference start position. The position b1 is set as the acceleration start timing. With this configuration, acceleration can be started immediately after being released from the nip between the paper feed roller 22 and the retard roller 24. Even if acceleration of the PF drive speed is started, simultaneous feeding can be performed while maintaining a predetermined gap Lgap between the subsequent sheets in the subsequent conveyance process.

  In addition, while the PF drive speed is maintained in the first constant speed range, the ASF drive speed eventually shifts to deceleration. During this deceleration process, the ASF drive speed gradually becomes slower than the PF drive speed. If the specified gap Lgap is opened in the process, the ASF drive speed can be shifted to acceleration immediately after the stop to make the stop waiting time substantially zero. Furthermore, the acceleration of the ASF drive c2 can be started in the middle of deceleration before stopping. At this time, the speed synthesis method may be performed in the same manner as the PF drive amount.

  In addition, even when acceleration of the next ASF drive c2 is started while the ASF drive b2 is stopped or decelerated, during the period during which acceleration is slower than the PF drive speed, The interval of gradually widens. Therefore, the prescribed gap Lgap does not have to be secured at the timing when acceleration is started while stopping or decelerating the ASF drive speed. In short, it is sufficient that a predetermined gap Lgap is ensured between the preceding sheet and the preceding sheet until the succeeding sheet is conveyed to a position where the leading edge of the succeeding sheet is detected by the sheet detection sensor 33.

  (Modification 2) In the first embodiment, the PF motor 58 is temporarily stopped when the ASF motor 56 is stopped under the condition that the first transport speed and the second transport speed can be the same. It is not limited to this. For example, as shown in FIG. 16, the first transport speed V3 determined from the drive distance b2 based on the minimum distance condition of the acceleration / deceleration table VT, and the second transport speed V3 determined from the drive distance c1 based on the minimum distance condition of the acceleration / deceleration table VT. Under conditions where the same speed can be achieved, the PF motor 58 may not be stopped once after the interpage control position Ng, but may be driven by the driving distance a at the first transport speed V3. The CPU 43 obtains the fastest target speed (first transport speed) among the target speeds set in the acceleration / deceleration table VT that satisfies the condition that the ASF drive distance b2 is not less than the minimum distance, and the PF drive distance c1 is the minimum distance. The fastest target speed (second transport speed) among the target speeds set in the acceleration / deceleration table VT that satisfies the above conditions is obtained. Then, it is determined whether or not the first transport speed and the second transport speed are the same. If the first transport speed and the second transport speed are the same, the CPU 43 drives the PF motor 58 at the PF drive distance a (= b1 + c1). On the other hand, if the first transport speed and the second transport speed are not the same, the PF motor 58 is driven twice with the PF drive distance b1 and the PF drive distance c1.

  Here, it is sufficient if the first transport speed and the second transport speed are the same within a predetermined allowable range. For example, when the second driving in which the PF driving distance a is driven at one time can complete the paper transport in a shorter time than the first driving in which the PF motor 58 is temporarily stopped halfway, the first transport speed and the second transport speed An allowable range is given to the determination so that the conveyance speed is slightly different even if it is slightly different. Further, the required transport time when the PF motor 58 is temporarily stopped and switched to high speed, and the required transport time when the PF driving distance a is driven at one time at the first transport speed without being stopped midway, When the calculation is performed using the data of the acceleration / deceleration table VT and it is determined that the latter required transfer time is shorter than the former required transfer time, the second method is used to drive the PF drive distance a at a time by the latter method. A configuration for selecting driving can also be employed. According to these configurations, since the sheet can be transported to the next printing position quickly, it is possible to improve the printing throughput. Since the preceding paper does not stop once in the middle, after the ASF motor 56 is stopped, the time required for the preceding paper P1 to be conveyed by the interpage control distance Lgap is shortened, and the ASF motor 56 is equivalent to the interpage control distance Lgap. The waiting time for waiting for the PF drive can be shortened. For example, when the paper passes through the inter-page control position Ng in the middle of paper discharge, the feeding of the next succeeding paper (cueing) can be completed quickly, and the printing start time can be advanced, thereby contributing to the suppression of a decrease in printing throughput.

  (Modification 3) In the first embodiment, when it is determined in step S30 in FIG. 10 that the interpage control position Ng is exceeded, from the conveyance start position (immediate stop position) to the interpage control position Ng (predetermined position). First, the conveyance drive is performed at the first conveyance speed according to the distance, and the conveyance drive is performed at the second conveyance speed according to the distance from the interpage control position Ng to the conveyance end position (next stop position). As a result, when the condition that the second transport speed is greater than the first transport speed is satisfied, the PF motor 58 is temporarily stopped at the interpage control position Ng (predetermined position), and from the first transport speed before and after the stop. The configuration is changed to the second transport speed. At this time, the PF motor 58 is temporarily stopped when the relationship between the transport speeds before and after the ASF motor 56 stops at a predetermined position satisfies the second transport speed> the first transport speed. The PF motor 58 is temporarily stopped when the relationship between the transport speeds before and after the stop at the position satisfies the second transport speed> the first transport speed. On the other hand, the following configuration can also be adopted. That is, when it is determined that the inter-page control position Ng is exceeded (S30), the transport distance from the transport start position to the predetermined position (first transport distance) and the transport distance from the predetermined position to the paper feed end position (second transport) The first transport speed and the second transport speed are acquired from the distance) with reference to the acceleration / deceleration table (speed control data). Then, it is determined whether or not a condition that the second transport speed is higher than the first transport speed is satisfied. In this case, the transport speed of the PF motor 58 may be used as the first transport speed and the second transport speed, but the transport speed of the ASF motor 56 can also be used. When the transport speed of the PF motor 58 is used, the first transport speed determined from the transport distance b1 is compared with the second transport speed determined from the transport distance c1. On the other hand, when the transport speed of the ASF motor 56 is used, the first transport speed determined from the transport distance b2 is compared with the second transport speed determined from the transport distance c2 (or Lgap + c2). In either case, when the second transport speed> the first transport speed is satisfied, the driving of the PF motor 58 is temporarily stopped at a predetermined position. As for the ratio of the first transport speed and the second transport speed, there is a positive correlation between the ASF drive and the PF drive. Therefore, when ASF drive satisfies the first transport speed> the first transport speed, the PF Even in driving, the second transport speed> the first transport speed is satisfied at a very high rate. The above configuration can also be applied to the second embodiment. However, in the second embodiment, the second transport speed is obtained from the transport distance from the acceleration table reference start position E to the next stop position.

  (Modification 4) In the above embodiment, the interpage control position is set to a position G slightly downstream of the nip point between the paper feed roller 22 and the retard roller 24 in the paper feed direction. It is not limited to. A position that is downstream of the nip point in the paper feeding direction and upstream of the detection position of the paper detection sensor 33 is sufficient. In this way, if the inter-page control position is set to a position within the range between the nip point and the detection position, before the subsequent sheet is conveyed to the position where the leading edge of the subsequent sheet is to be detected in advance, It is possible to secure the gap Lgap by performing interpage control.

  (Modification 5) In the above-described embodiment, the configuration has an acceleration / deceleration table. However, a configuration without an acceleration / deceleration table may be used. The acceleration and deceleration are set to a linear gradient, and the period (speed) with respect to the distance in the acceleration region and the deceleration region is obtained by calculation using a linear equation. For example, when the acceleration gradient A and the distance are Dx, the period Ta is calculated by Ta = A · Dx. Similarly, in the deceleration area, if the deceleration gradient −B, the period Ta is calculated by Ta = −B · Dx. One or more points where the gradient of acceleration or deceleration changes may be set in at least one of the acceleration region and the deceleration region. Also in this case, the period with respect to the distance can be obtained by simple calculation.

  (Modification 6) The stop of the conveying means when changing from the first conveying speed to the second conveying speed is not limited to waiting for the feeding start of the subsequent medium by the feeding means. If it is after the area conveyed by both the feeding means (paper feed roller 22) and the conveying means (paper feed roller 29), the conveying means may be temporarily stopped during the conveyance by the feeding means. . For example, it may be before the feeding means is temporarily stopped or after the feeding of the succeeding medium is started.

  (Modification 7) In the above embodiment, the ASF motor 56 and the PF motor 58 are provided separately, and the paper feed roller 22 and the paper feed roller 29 are driven by different drive sources. The paper feed roller 29 may share one motor (drive source). In this case, the electromagnetic clutch is disconnected from the motor and the paper feed roller 22 is temporarily stopped at a predetermined position.

  (Modification 8) When the sheet passing through the inter-page control position Ng is performed, if the transport speed (target speed) of the PF motor 58 determined from the transport distance before and after the inter-page control position Ng is different, the first In the embodiment, the PF drive is temporarily stopped, or in the second embodiment, the control is performed to synthesize the speed profile determined from the acceleration / deceleration table. However, two speed profiles having different target speeds are synthesized to have different values of 2 An acceleration / deceleration table (speed control data) having a speed profile dedicated to synthesis having two target speeds (constant speed ranges) may be provided.

  (Modification 9) In the above-described embodiment, when a sheet is transported across the interpage control position Ng, the sheet is stopped at the interpage control position Ng, and then the preceding sheet is advanced by the interpage control distance Lgap by PF driving. After waiting for the sheet to be conveyed, the ASF drive is started to feed the subsequent sheet. On the other hand, the ASF driving is started immediately without waiting for the distance corresponding to the inter-page control distance Lgap, and the ASF driving is performed when the paper feed distance shorter than the PF-driven transport distance by the inter-page control distance Lgap is reached. It is good also as a structure to stop. Even with this configuration, at least at the stage where the conveyance of the paper is finished and both the ASF driving and the PF driving are stopped, a predetermined gap can be secured between the trailing edge of the preceding sheet and the leading edge of the succeeding sheet.

  (Modification 10) The drive source is not limited to a DC motor, and other electric motors can be used. For example, a stepping motor can be used. As the stepping motor, for example, a two-phase excitation method, a one-phase excitation method, a one-two-phase excitation method, or a microstep drive (vernier drive) method can be adopted. Further, the rotor may be any of a permanent magnet type (PM type), a gear-shaped iron core type (VR type), and a hybrid type (HB type).

  (Modification 11) In the above embodiment, the drive control of the ASF motor and the PF motor is realized by software by the CPU 43 executing a program, but the method is not limited to the method by software. For example, paper feed / paper feed processing may be realized by hardware using a control circuit (custom IC or the like), and paper feed / paper feed processing may also be realized by a combination (cooperation) of hardware and software. .

  (Modification 12) The present invention is not limited to the ink jet printer. You may apply to other serial printers, such as a dot impact type printer. The present invention can also be applied to a recording apparatus that includes a line head type recording head having nozzles capable of recording over the entire area of the maximum sheet width and performs recording on a medium without moving the recording head in the main scanning direction. . In this case, the medium to be recorded by the line head is transported at a constant speed in the transport direction, and recording by the line head is performed on the medium moving in the transport direction.

  (Modification 13) In the above embodiment, the recording apparatus is embodied as an ink jet printer. However, the present invention can also be applied to other liquid ejecting recording apparatuses that eject liquid other than ink as liquid. Here, “recording” is not limited to recording by printing, but includes, for example, recording in which a liquid material containing a material used for a circuit wiring pattern is ejected to draw a wiring pattern on a substrate as a medium. For example, a liquid ejecting apparatus (recording apparatus) that ejects a liquid material in which materials such as electrode materials and color materials used for manufacturing liquid crystal displays, EL (electroluminescence) displays, and surface-emitting displays are dispersed or dissolved. Also good. In this case, a predetermined pattern such as a pixel pattern or a wiring pattern is drawn on the substrate by ejecting droplets. For example, when sheet-like substrates are sequentially fed one by one by a feeding unit, and a predetermined pattern such as a wiring pattern is drawn by a liquid ejecting method on a fed substrate by a recording unit, the interval between the substrates as a medium is set. Since the speed can be changed without opening and complicated speed control, the throughput can be improved and the productivity can be improved.

Hereinafter, the technical idea grasped | ascertained from the said embodiment and each modification is described.
(1) The control means transports the preceding medium at the first transport speed without performing shift control under the condition that the first transport speed and the second transport speed can be made substantially the same. Item 11. The recording apparatus according to any one of Items 1 to 10.

  (2) In the case where the preceding medium is transported through the predetermined position, the control unit is configured to supply the feeding unit more than a first transporting speed that is a transporting speed of the preceding medium by the feeding unit and the transporting unit. Acceleration control for accelerating from the first transport speed to the second transport speed under the condition that the second transport speed, which is the transport speed of the preceding medium by the transport means after the start of transport of the subsequent medium by The recording apparatus according to claim 1, wherein the recording apparatus is a technical idea (1).

  (3) The composition is performed by instructing a speed corresponding to a position from a position value corresponding to a speed value in a constant speed region of the first speed control data in the second speed control data. The recording apparatus according to claim 3.

  (4) The first speed control data and the second speed control data are speed control data including a data group indicating a correspondence relationship between a position value and a speed value, one each in an acceleration process and a deceleration process. The recording apparatus according to any one of claims 3 to 11, and the technical idea (3).

  (5) The second transport speed is determined by selecting the fastest transport speed satisfying that the remaining transport distance transported at the first transport speed is not less than the minimum distance. The recording apparatus according to claim 10.

  (6) The apparatus further includes detection means for detecting the leading edge of the succeeding medium between the engagement positions where the feeding means and the conveying means are engaged with the medium to apply a conveying force to the medium. The recording apparatus according to claim 1, wherein the preceding medium is set at a position upstream of a position where the preceding medium can be detected by the detecting unit.

  (7) First speed control data in which the first transport speed is set as a target speed and a speed corresponding to a position value is set; and the second transport speed is set as a target speed and a speed corresponding to the position value Storage means for storing the second speed control data in which the speed control data is set, and in the shifting step, the speed control data to be referred to for speed control of the transport means is transferred from the middle of the first speed control data to the second speed control data. 13. The medium conveying method according to claim 12, wherein a shift control for switching from the first conveying speed to the second conveying speed is performed by switching to a corresponding halfway in the acceleration process of the two-speed control data.

(A), (b) The model side view explaining operation | movement of the automatic paper feeder in one Embodiment. FIG. FIG. 3 is a schematic side view showing a transport mechanism that transports paper from an automatic paper feeder. FIG. 5 is a schematic plan view for explaining paper feeding that passes through a page-to-page control position. FIG. 2 is a block diagram illustrating an electrical configuration of the printer. The table figure which shows an acceleration / deceleration table. The graph which shows the speed waveform of an acceleration / deceleration table. The graph which shows a velocity waveform. The graph which shows a velocity waveform. 6 is a flowchart illustrating a paper conveyance control process. The graph which shows a velocity waveform. The graph which shows a velocity waveform. The figure which shows the graph and acceleration table of a speed waveform. The flowchart which shows a control process between pages. The graph which shows the velocity waveform of a modification. The graph which shows the velocity waveform of the modification different from FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Printer as recording apparatus, 13 ... Automatic paper feeder (ASF) as feeding means, 15 ... Hopper as movable part, 18 ... Carriage constituting recording means, 19 ... Recording head constituting recording means, DESCRIPTION OF SYMBOLS 21 ... Compression spring, 22 ... Paper feed roller, 24 ... Retard roller, 29 ... Paper feed roller which comprises conveyance means, 30 ... Paper discharge roller, 33 ... Paper detection sensor, 35 ... Host computer, 40 ... Control part, 43 ... Constructing control means and CPU as judgment means, 45... ROM as storage means, 50... Motor driver constituting control means, 52... Motor driver constituting control means, 56... ASF as first drive source Motor 58 ... PF motor as second drive source, 65 ... Paper feed amount counter as position detecting means, VT1 ... First speed control data Acceleration / deceleration table, VT2 ... Acceleration / deceleration table as second speed control data, V1 ... Target speed as first transport speed, V2 ... Target speed as second transport speed, Nx ... Count value indicating transport position, P1 ... Previous sheet as preceding medium, P2 ... Subsequent sheet as subsequent medium, P ... Paper as medium, E ... Refer to acceleration table as position of zero speed on acceleration gradient extension when accelerating from first transport speed Start position, F ... acceleration start timing position, a, b1, b2, c1, c2 ... transport distance, Da1, Da2 ... movement distance, Db1, Db2 ... movement distance.

Claims (12)

A recording apparatus comprising: a feeding unit that feeds a medium; a conveying unit that conveys the medium fed by the feeding unit; and a recording unit that records on the medium conveyed by the conveying unit. ,
The preceding medium to be fed first is transported by both the feeding means and the transporting means, and after the preceding medium is transported to a predetermined position where it is not transported by the feeding means, the feeding means is stopped or After decelerating and waiting until the distance between the preceding medium and the succeeding medium reaches a predetermined distance, the feeding means starts to accelerate the succeeding medium so that the preceding medium and the succeeding medium are continuously conveyed. Control means for drivingly controlling the feeding means and the conveying means;
In the case where the preceding medium is transported through the predetermined position, the control means includes a first transport speed, which is a transport speed of the preceding medium by the feeding means and the transport means, and a succeeding medium by the feeding means. After the start of acceleration, the transport means is moved to the first transport under the condition that the transport speed of the subsequent medium by the feeding means or the second transport speed that is the transport speed of the preceding medium by the transport means is different. A recording apparatus that performs shift control for shifting from a speed to a second transport speed. The first transport speed is such that when the preceding medium is transported to stop at both the feeding unit and the transport unit and at the predetermined position, the preceding medium is moved from the stop position immediately before the transport to the predetermined position. The transport speed of the feeding means and the transport means when transporting without stopping to the position,
The second transport speed is such that the succeeding medium is transported without stopping to the next stop position after the feeding means starts accelerating after the distance between the preceding medium and the succeeding medium reaches the predetermined distance. The speed of the feeding means when the speed is zero on the acceleration gradient extension of the acceleration at which the acceleration from the first transport speed can be started at least from the acceleration start position after the predetermined position. To the next stop position is one of the transport speeds of the transport means when transporting without stopping, and the control means determines that the second transport speed is the first transport speed according to the transport distance. The recording apparatus according to claim 1, wherein control that satisfies a higher speed relationship is executed. First speed control data in which the first transport speed is set as a target speed and a speed corresponding to a position value is set, and the second transport speed is set as a target speed and a speed corresponding to the position value is set. Storage means for storing the second speed control data,
When the control means shifts the transport means from the first transport speed to the second transport speed, the reference speed control data is accelerated from the middle of the first speed control data. The recording apparatus according to claim 1, wherein the recording apparatus is switched to a corresponding halfway in the process.   The control means retrieves the second speed control data, obtains a position where the same speed as the target speed of the first speed control data is set, and performs the transport in which the preceding medium passes through the predetermined position First, the speed of the transport means is controlled according to the first speed control data to accelerate to the first transport speed and is maintained at a constant speed at the first transport speed, and transported by both the feeding means and the transport means When reaching a predetermined acceleration start position that has passed the region, the reference speed control data is switched from the first speed control data to the second speed control data, and from the continuation of the position value obtained by the search, 4. The recording apparatus according to claim 3, wherein speed control is performed according to the two speed control data. Storage means for storing speed control data in which a speed according to a position value in a shifting process from the first transport speed to the second transport speed is set;
The control means accelerates the preceding medium from the first transport speed to the second transport speed by controlling the transport means to a speed corresponding to a position value in the speed control data in the speed change process. The recording apparatus according to claim 1 or 2. A storage means for storing data of a calculation formula capable of calculating a speed according to a position value in a shifting process from the first transport speed to the second transport speed;
2. The control device according to claim 1, wherein the control unit performs the shift control by controlling the transport unit so that the speed is calculated according to a position value using a calculation formula in the shift process. 2. The recording apparatus according to 2.   The control means does not perform the shift control for shifting the conveying means from the first conveying speed to the second conveying speed under the condition that the second conveying speed is lower than the first conveying speed. The recording apparatus according to claim 1, wherein: A first drive source for driving the feeding means;
A second drive source for driving the transport means;
The recording apparatus according to claim 1, wherein the control unit drives and controls the first drive source and the second drive source.   The second transport speed depends on the transport distance from the predetermined position of the first drive source to the next stop position, or the transport distance from the position at the zero speed of the second drive source to the next stop position. The recording apparatus according to claim 8.   A minimum distance corresponding to the sum of a moving distance necessary for acceleration up to the conveying speed and a moving distance necessary for decelerating from the conveying speed is determined, and the control means conveys the conveyance passing the predetermined position. The fastest transport speed that satisfies that the transport distance from the start position to the position at which shifting from the first transport speed to the second transport speed starts is equal to or greater than the minimum distance is selected and the first The recording apparatus according to claim 1, wherein one transport speed is determined.   The first transport speed is determined by selecting a lower one of the transport speeds separately determined by the feeding means and the transport means, and the second transport speed is transported at the first transport speed. The recording apparatus according to claim 10, wherein the recording apparatus is determined by selecting the highest conveyance speed among the conveyance speeds satisfying that the remaining conveyance distance is not less than the minimum distance. Medium transport in a recording apparatus comprising: a feeding unit that feeds a medium; a transport unit that transports the medium fed by the feeding unit; and a recording unit that records on the medium transported by the transport unit A method,
When the preceding medium that is fed first passes from a position in a region where the preceding medium is transported by both the feeding unit and the transporting unit to pass through a predetermined position that is not transported by the transporting unit. Is
Conveying the preceding medium by both the feeding means and the conveying means, and stopping or decelerating the driving of the feeding means after the preceding medium is conveyed to a predetermined position where it is not conveyed by the conveying means; ,
The feeding means waits until the distance between the preceding medium and the succeeding medium reaches a predetermined distance, and then starts the acceleration of the succeeding medium by the feeding means to continuously convey the preceding medium and the succeeding medium. And a control step for driving and controlling the transport means;
The first conveying speed of the preceding medium conveyed by both the feeding means and the conveying means, and the conveying speed of the subsequent medium by the feeding means after the start of acceleration of the subsequent medium by the feeding means or the conveying means And a shift step for performing shift control for shifting the speed from the first transport speed to the second transport speed under the condition that the second transport speed that is the transport speed of the preceding medium is different from the first transport speed. Media transport method in

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