JP4877301B2 - Image recording apparatus and recording paper conveyance control method - Google Patents

Description

  The present invention includes an image recording apparatus that includes a recording head that records an image by ejecting ink onto a recording sheet, and that can record an image on both the first surface and the second surface of the recording sheet, and the recording sheet. The present invention relates to a conveyance control method.

  2. Related Art Inkjet image recording apparatuses capable of recording images on both sides of a recording sheet are known. In this type of image recording apparatus, since the end of the recording paper on which the image is recorded on the first surface (front surface) has been curled conventionally, the recording head is used when recording the image on the second surface (back surface). There is a problem that the end of the recording paper comes into contact with the nozzle and the carriage, and proper image recording is not performed.

  Patent Document 1 discloses a recording apparatus configured such that a recording sheet does not curl upward when image recording is performed on a second surface. In this recording apparatus, the recording paper is stopped for a predetermined time in a state where the leading edge of the recording paper on which the image is recorded on the first surface is in the loop-shaped reverse conveyance path. As a result, a downward curl having the same shape as the reverse conveyance path is positively attached to the recording paper, and the recording paper does not curl upward during image recording on the second surface.

JP-A-2005-74745

  However, in an inkjet image recording apparatus, when an image is recorded on the first surface, so-called cockling may occur in which the recording paper is deformed so as to wave in the width direction. This cockling cannot be completely corrected by simply waiting the recording paper for a predetermined time in the direction opposite to the curling direction as in the above-described recording apparatus of Patent Document 1. As a result, when an image is recorded on the second surface after the image is recorded on the first surface, there arises a problem that the recording paper contacts the recording head. Note that the degree of deformation of the cockling of the recording paper varies depending on the type of recording paper such as postcard, plain paper, thin paper, and the like.

  Therefore, the present invention has been made in view of the above problems, and an image recording apparatus capable of correcting a recording sheet deformed by recording an image on the first surface substantially uniformly regardless of its rigidity, It is another object of the present invention to provide a recording paper conveyance control method.

(1) In order to achieve the above object, the present invention comprises a recording head for recording an image by ejecting ink onto a recording sheet, and images are recorded on both the first surface and the second surface of the recording sheet by the recording head. It is configured as a recordable image recording apparatus. The image recording apparatus includes a retracting unit, a moving member, a conveyance control unit, and a drive control unit. The evacuation unit is provided in the conveyance path on the downstream side in the conveyance direction with respect to the recording head. The retracting unit is configured to retract a part of the recording paper to the outside of the transport guide surface of the transport path. The moving member is configured to be movable between a first position where the recording sheet can pass through the conveyance path and a second position where the recording sheet is immersed in the retracting portion. The conveyance control means is in a first posture in which the recording sheet is supported by the retracting portion after the image is recorded on the first surface of the recording sheet and before the image is recorded on the second surface by the recording head. Sometimes the recording paper is stopped. The drive control means continuously moves the moving member from the first position to the first position again through the second position with the recording paper stopped in the first posture by the conveyance control means. .

  The recording paper on which the image is recorded on the first surface by the recording head may generate so-called cockling that is deformed so as to wave in the width direction. This phenomenon appears remarkably on a recording sheet having low rigidity (weak stiffness), and the deformation tends to be smaller as the rigidity of the recording sheet increases.

  The recording sheet on which the image is recorded on the first surface is temporarily stopped by the conveyance control means in the first posture before the image is recorded on the second surface. During the temporary stop, the drive control means supplies a driving force to the moving member, and continuously moves the moving member from the first position to the first position again through the second position. At this time, the temporarily stopped recording paper is shifted from a state in which no load is applied by the moving member to a state in which the recording member is pressed by the moving member toward the retracting portion, and the load is applied again. Transition continuously to no state. By such continuous movement of the moving member, the recording sheet is deformed into a bent shape or a curved shape. As a result, since the recording sheet is pinched in the width direction, deformation such as cockling that has occurred in the width direction is reduced. In addition, the recording paper is not kept in a state where a load is applied for a certain period of time, but continuously changes from a no-load state due to the moving member to a no-load state again after being loaded. Brazing is applied according to the rigidity of the.

  In the present specification, unless otherwise specified, the “direction” is represented by a straight line having opposite directions such as + and −, for example. For example, it is represented by an arrow having one arrow head such as + or-.

(2) The image recording apparatus of the present invention further includes a feed roller, a first transport path, a support member, a second transport path, and a pair of feed rollers. The feeding roller contacts the recording paper stacked on the tray and feeds the recording paper. The first conveyance path is formed in a curved shape between the feeding roller and the recording head, and the recording paper is placed so that the surface opposite to the surface on which the feeding roller contacts is opposed to the recording head. Transport. The support member is provided on the downstream side in the transport direction from the recording head, and supports the recording paper that has passed through the recording head. The second transport path is branched from the downstream side in the transport direction with respect to the support member, and is connected to the upstream side in the transport direction of the first transport path. The pair of feed rollers are provided on the downstream side of the support member in the transport direction, and are configured to be able to rotate forward and reverse, and sandwich the recording sheet that has passed through the recording head to rotate the recording sheet to the outside. The recording paper is switched back by being conveyed toward the reverse or reversely conveyed to the second conveying path. In this case, the retracting portion includes the support member and the pair of feed rollers, and is formed between the support member and the pair of feed rollers, and has a branch port that guides the recording sheet to the second transport path. It is what you have. In addition, the conveyance control unit is configured to record the recording paper in the first posture in which the downstream end in the conveyance direction of the recording paper is sandwiched between the pair of feed rollers, and the upstream end in the conveyance direction is supported by the support member. Is to stop. In the second position, the moving member presses a portion of the recording sheet stopped by the conveyance control unit between the support member and the pair of feed rollers toward the branch port. Has been placed.

(3) The moving member can guide the upstream end of the recording sheet, which is sandwiched between the pair of feed rollers, from the first position to the second conveying path through the second position. The third position is supported so as to be movable.

  Thereby, the moving member can be used for both the use for correcting cockling and the use for guiding the sheet to the second conveyance path.

(4) The transport control unit assumes a second posture in which the upstream end in the transport direction of the recording paper reaches the branch port after the moving member is returned to the first position by the drive control unit. The recording paper is conveyed until the recording paper is stopped in the second posture. The drive control means moves the moving member from the first position to the third position in a state where the recording paper is stopped in the second posture by the conveyance control means.

  When the recording sheet is conveyed in a state where the moving member is in contact with the recording surface of the recording sheet or in a state where the recording surface is in contact with the conveyance guide surface of the conveyance path due to the movement member pressing the recording sheet, May be rubbed against the moving member or the conveying guide surface, and the ink on the recording surface may adhere to the moving member or the conveying guide surface and become dirty. However, according to the image recording apparatus of the present invention, the conveyance control means does not convey the recording paper in a state where the moving member is in contact with the recording paper, but removes the recording paper after the moving member is returned to the first position. It is to be transported. Therefore, the ink stain as described above does not occur.

(5) The drive control means continues the moving member from the first position to the first position again through the second position in a state where the recording paper is stopped in the first posture by the conveyance control means. And then moving the moving member from the first position to the third position.

  As a result, the time required from the time when the moving sheet is rubbed to the recording paper to the switching of the path of the recording paper is shortened, and as a result, the transport time required for image recording is shortened, thereby improving the throughput of the image recording processing.

(6) It is preferable that the second position is a position where the moving member presses the first surface of the recording sheet to bend and deform the recording sheet by a predetermined amount.

(7) It is preferable that the moving member is rotatably supported around one end side as a rotation center, and the other end side can be displaced from the first position to the second position in accordance with the rotation operation.

  In this configuration, when the moving member is rotated and the other end side is displaced from the first position to the second position, the other end side of the moving member contacts the sheet and is sandwiched between the pair of feed rollers. The sheet being pressed is pressed toward the second conveying path.

(8) The pair of feed rollers includes a driving roller that rotates by receiving a driving force and a driven roller that rotates by following the driving roller. The moving member is pivotally supported on one end side so that the driven roller is pivotally supported, and is extended upstream in the conveying direction, and is supported so as to be pivotable about the rotation shaft of the driving roller.

(9) An auxiliary roller capable of contacting the recording paper is rotatably supported on the other end side of the moving member.

  As a result, the roller surface of the auxiliary roller is brought into contact with the sheet, so that there is no fold line on the sheet, and the sheet is not irreversibly deformed.

(10) The present invention is provided in a recording head for recording an image by ejecting ink onto a recording sheet, and a conveying path downstream in the conveying direction from the recording head, and a part of the recording sheet is conveyed in the conveying path. A retracting portion that retracts to the outside of the guide surface, and a moving member that is movable between a first position where the recording sheet can pass through the conveyance path and a second position where the recording sheet is inserted into the retracting portion, It can also be understood as a recording paper conveyance control method applied to an image recording apparatus capable of recording images on both the first and second surfaces of the recording paper by the recording head. This transport control method includes a first step and a second step. In the first step, after the image is recorded on the first surface of the recording paper, the recording paper is in the first posture supported by the retracting portion before the image is recorded on the second surface by the recording head. Sometimes the recording paper is stopped. In the second step, the moving member is continuously moved from the first position to the first position again through the second position in a state where the recording sheet is stopped in the first posture by the first step. .

  According to the present invention, it is possible to correct a recording sheet deformed by recording an image on the first surface substantially uniformly regardless of its rigidity.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings as appropriate. The embodiment described below is merely an example of the present invention, and it is needless to say that the embodiment of the present invention can be changed as appropriate without departing from the gist of the present invention.

  FIG. 1 is an external perspective view of a multifunction machine 10 according to an embodiment of the present invention. The multifunction machine 10 is equipped with an inkjet printer unit 11 capable of recording an image on both the front surface (first surface) and the back surface (second surface) of the recording paper, so that the recording paper can be printed without increasing the size of the apparatus. The generated cockling and other deformations can be corrected with a simple configuration to improve the reliability of backside recording.

  The multifunction machine 10 has various functions such as a facsimile function, a printer function, a scanner function, and a copy function. The printer function has a double-sided image recording function for recording images on both sides of the recording paper. Functions other than the printer function are arbitrary. For example, the image recording apparatus of the present invention may be implemented as a printer having only a printer function that does not have a scan function, a copy function, or a facsimile function.

  The multifunction machine 10 is mainly provided with a printer unit 11 provided at the lower part, a scanner part 12 provided at the upper part, and an operation panel 40 provided at the upper part of the front face.

  The printer unit 11 has an opening 13 formed in the front, and a paper feed tray 20 (an example of a tray according to the present invention) and a paper discharge tray 21 are provided in two upper and lower stages inside the opening 13. The paper feed tray 20 is for loading recording paper. The recording sheets stacked on the sheet feeding tray 20 are fed (feeded) into the printer unit 11 and are discharged to the sheet discharge tray 21 after a desired image is recorded. The paper feed tray 20 and the paper discharge tray 21 are configured to be inserted into and removed from the printer unit 11 through the opening 13.

  The scanner unit 12 is configured as a so-called flat bed scanner. A document cover 30 is provided on the upper portion of the scanner unit 12. The document cover 30 is provided as a top plate of the multifunction machine 10, and a platen glass (not shown) is disposed under the document cover 30. The document is placed on the platen glass and read by the scanner unit 12 while being covered with the document cover 30.

  The operation panel 40 is for operating the printer unit 11 and the scanner unit 12 and is provided with various operation buttons and a liquid crystal display unit. The user can set various functions and perform operations by operating the operation panel 40. For example, setting of the type of recording paper (plain paper or postcard) as a recording paper, setting of a single-sided recording mode for recording an image only on the surface of the recording paper, setting of a double-sided recording mode for recording an image on both front and back sides, Setting of the resolution (draft mode or photo mode) can be instructed via the operation panel 40.

  Next, an outline of the configuration of the printer unit 11 will be described with reference to FIG. FIG. 2 is a longitudinal sectional view showing the structure of the printer unit 11. The printer unit 11 is fed mainly by a paper feed tray 20 on which recording paper is stacked, a paper feeding unit 15 that feeds (feeds) recording paper from the paper feed tray 20, and a paper feeding unit 15. A transport path 23 through which the recording paper passes, a recording section 24 that records an image on the recording paper by ejecting ink droplets onto the recording paper transported through the transport path 23, and a paper discharge tray 21 from which the recording paper is discharged. And a path switching unit 41 (an example of a moving member of the present invention) that is disposed between the recording unit 24 and the paper discharge tray 21 and switches a recording paper conveyance path in order to record an image on the back surface. A reversing guide path 16 (this book) guides the recording sheet whose transport path has been switched by 41 to the upstream side (hereinafter simply referred to as “upstream side”) in the transport direction of the recording sheet from the feeding unit 15 and the transport path 23. An example of a second transport path of the invention) There. In the present embodiment, the path switching unit 41 not only switches the recording paper conveyance path, but also plays a role of pressing and crimping the trailing edge of the recording paper.

  A paper feed tray 20 is provided below the feeding unit 15. The paper feed tray 20 is disposed on the bottom side of the printer unit 11 and is configured in a rectangular box shape with an open top surface. The paper feed tray 20 has a bottom plate 113 that constitutes a paper placement surface. A plurality of recording sheets are stacked on the bottom plate 113. The recording paper loaded on the paper feed tray 20 is fed to the transport path 23 by a paper feed roller 25 (an example of the feed roller of the present invention) provided in the paper feed unit 15.

  The paper discharge tray 21 is disposed above the paper feed tray 20. A flap 17 is attached to the front end (left end in FIG. 2) of the paper discharge tray 21. The flap 17 forms a reverse guide passage 16 together with a guide member 34 (an example of a support member of the present invention) and a guide member 35 described later. Note that the guide member 34, the first roller 45 and the second roller 46 of the path switching unit 41, which will be described later, and a branch port 36A of the downstream part 36, which will be described later, realize the retreating part of the present invention.

  When the printer unit 11 records an image only on one side (front surface) of the recording paper, the recording paper fed by the paper feeding roller 25 is guided to make a U-turn from below to above along the conveyance path 23. Then, the recording unit 24 is reached, and an image is recorded on the surface by the recording unit 24, and then is discharged to the paper discharge tray 21.

  On the other hand, when images are recorded on both sides (front and back) of the recording paper, the recording paper on which the image is recorded on the front surface is reversely guided by the path switching unit 41 so that the front surface is in contact with the paper feed roller 25. The paper is guided to the passage 16 and fed again to the transport path 23 by the paper feed roller 25. Then, after an image is recorded on the back surface of the recording paper by the recording unit 24, the image is discharged to the paper discharge tray 21.

  The recording unit 24 is disposed in the middle of the conveyance path 23 and includes a carriage 38 and a recording head 39 (an example of the recording head of the present invention). The recording head 39 is mounted on the carriage 38 with the nozzle surface exposed to the transport path 23. The carriage 38 is configured to reciprocate along the guide rails 55 and 56 together with the recording head 39 in the main scanning direction (the direction perpendicular to the paper surface of FIG. 2). In the reciprocating process of the carriage 38, the recording head 39 ejects ink supplied from an ink cartridge (not shown) as a minute ink droplet onto a recording sheet conveyed on the platen 42 (see FIG. 3). Thereby, an image is recorded on the recording paper. The recording sheet on which the image is recorded by the recording unit 24 may have a so-called cockling in which the width direction is undulated. However, as will be described later, the trailing edge of the recording sheet is attached by the path switching unit 41. As a result, the cockling is reduced.

  Next, the configuration of the printer unit 11 will be described in detail with reference to FIG. FIG. 3 is a partially enlarged sectional view of the printer unit 11. In FIG. 3, the recording unit 24 is omitted for convenience of explanation.

  The feeding unit 15 includes a paper feed roller 25, a paper feed arm 26, and a drive transmission mechanism 27. The paper feed roller 25 is disposed on the upper side of the paper feed tray 20. The paper feed roller 25 feeds the recording paper loaded on the paper feed tray 20 to the transport path 23, and is rotatably supported at the tip of the paper feed arm 26. The sheet feed roller 25 is rotationally driven through a drive transmission mechanism 27 using an SF motor (Sheet Feed Motor) 74 (see FIG. 10) as a drive source. The drive transmission mechanism 27 is composed of a plurality of gears arranged substantially linearly, and is configured by meshing them.

  The paper feed roller 25 is provided with a rotary encoder 86 (see FIG. 10). The rotary encoder 86 detects the pattern of an encoder disk (not shown) that rotates together with the paper feed roller 25 with an optical sensor. Based on the signal detected by the optical sensor, the rotation of the paper feed roller 25 is controlled by the control unit 84 described later.

  The paper feed arm 26 has a base end portion supported by a base shaft 28 and is configured to be rotatable about the base shaft 28 as a rotation center axis. For this reason, the paper feed arm 26 can move up and down so as to be able to contact and separate from the paper feed tray 20. The paper feed arm 26 is urged to rotate downward by its own weight or an urging force such as a spring. For this reason, the paper feed roller 25 at the tip of the paper feed arm 26 is normally in contact with the upper surface of the recording paper in the paper feed tray 20. The paper feed arm 26 is configured to retract upward when the paper feed tray 20 is inserted into and removed from the printer unit 11.

  When feeding recording paper from the paper feed tray 20, the paper feed arm 26 is biased downward and the paper feed roller 25 is pressed against the recording paper on the paper feed tray 20. The paper roller 25 is rotated. As a result, a frictional force is generated between the roller surface of the paper feed roller 25 and the recording paper, and the recording paper at the uppermost position is sent out to the conveyance path 23 side (left side in FIG. 3) by this frictional force.

  When the leading edge of the recording sheet comes into contact with the separation inclined plate 22 provided in the sheet feeding tray 20, the recording sheet is guided upward and sent to the conveyance path 23 along the arrow 14. When the uppermost recording paper is sent out by the paper feed roller 25, the recording paper immediately below it may be sent out together due to friction or static electricity, but this recording paper is restrained by contact with the separation inclined plate 22. Is done.

  The conveyance path 23 includes a curved curved path 23A (an example of a first conveyance path of the present invention) formed between the paper feed roller 25 and the recording unit 24, and a discharge path extending from the recording unit 24 to the paper discharge tray 21. And a paper path 23B. The curved path 23A reaches the separation inclined plate 22 from the paper feed roller 25, and thereafter turns upward and then bends in a U-shape to the front side (right side in FIG. 3) to reach the recording unit 24. Accordingly, the recording paper fed from the paper feed tray 20 by the paper feed roller 25 is recorded such that the surface opposite to the surface on which the paper feed roller 25 is in contact is opposed to the recording head 39 of the recording unit 24. Guided to the part 24 side. The paper discharge path 23 </ b> B extends from the recording unit 24 to the front side from the back side (left side in FIG. 3) of the multifunction machine 10 and communicates with the paper discharge tray 21.

  The conveyance path 23 is defined by an outer guide surface and an inner guide surface except for a portion where the recording unit 24 or the like is disposed. For example, the curved path 23 </ b> A on the back side of the multifunction machine 10 is formed by fixing the outer guide member 18 and the inner guide member 19 to the main body frame 53. In this case, the outer guide member 18 forms an outer guide surface, and the inner guide member 19 forms an inner guide surface. Moreover, the outer side guide member 18 and the inner side guide member 19 are opposingly arranged at predetermined intervals.

  A transport roller 60 and a pinch roller 61 are provided on the upstream side of the transport path 23 from the recording unit 24. These are paired. The pinch roller 61 is disposed so as to be in pressure contact with the lower side of the conveying roller 60. The conveyance roller 60 and the pinch roller 61 pinch the recording sheet conveyed through the curved path 23 </ b> A and convey it onto the platen 42.

  Further, a discharge roller 62 and a spur 63 (see FIGS. 5 and 6) are provided downstream of the recording unit 24 in the conveyance direction of the recording paper in the conveyance path 23 (hereinafter simply referred to as “downstream side”). Is provided. The paper discharge roller 62 and the spur 63 pinch the recorded recording paper and convey it further downstream (to the paper discharge tray 21 side). The conveyance roller 60 and the paper discharge roller 62 are rotated by the rotational driving force transmitted from the LF motor 71 (see FIG. 10).

  The transport roller 60 and the paper discharge roller 62 are driven using the LF motor 71 as a drive source. The driving of the transport roller 60 and the paper discharge roller 62 is synchronized and is intermittently driven during image recording. As a result, the recording sheet is image-recorded while being sent with a predetermined line feed width.

  The transport roller 60 is provided with a rotary encoder 87 (see FIG. 10). The rotary encoder 87 detects a pattern of an encoder disk (not shown) that rotates together with the transport roller 60 with an optical sensor, and the rotation of the transport roller 60 and the paper discharge roller 62 is based on a signal detected by the optical sensor. Be controlled. Further, before and after the image recording, the transport roller 60 and the paper discharge roller 62 are continuously driven, so that quick paper transport is realized.

  A registration sensor 102 (see FIG. 10) is provided upstream of the conveyance roller 60 in the curved path 23A. The registration sensor 102 includes a rotor 103 and an optical sensor (for example, a photo interrupter). The rotor 103 protrudes from the outer guide 18 to the curved path 23A and is disposed so as to cross the curved path 23A. The rotor 103 extends from a slit (not shown) formed in the outer guide 18 toward the curved path 23A, and can appear and disappear in the curved path 23A. In the present embodiment, the rotor 103 is elastically biased so as to always protrude into the curved path 23A. When the recording sheet conveyed through the curved path 23 </ b> A contacts the rotor 103, the rotor 103 is immersed in the outer guide 18. The optical sensor is turned ON or OFF by the appearance of the rotor 103. The control unit 84 determines the position of the leading edge or the trailing edge of the recording paper in the conveyance path 23 based on the signal output from the optical sensor.

  One end of the reversing guide path 16 is connected to the paper discharge path 23B of the transport path 23, and the other end is connected to the curved path 23A. The reverse guide passage 16 branches from a downstream portion 36 of the paper discharge path 23 </ b> B on the downstream side of the guide member 34 described later, and extends obliquely downward toward the paper feed tray 20. The downstream portion 36 has a branch port 36 </ b> A for guiding the recording paper from the paper discharge path 23 </ b> B to the reverse guide path 16. The branch port 36A is formed between the guide member 34 and a first roller 45 described later. The reversing guide passage 16 branched from the downstream side portion 33 still extends through the sheet feed tray 20 and the upstream side portion 37 in the vicinity of the separation inclined plate 22 that is the entrance of the curved path 23A. It is connected to the curved path 23A. The reversing guide path 16 formed in this way constitutes a reversing path that guides the recording paper having an image recorded on the surface thereof from the paper discharging path 23A to the paper feeding tray 20 again.

  The reverse guide passage 16 is partitioned by a first guide surface 32 and a second guide surface 33. The first guide surface 32 is formed by the surface of the guide member 34 disposed inside the main body frame 53 of the multifunction machine 10. The guide member 34 is provided on the downstream side of the recording unit 24. The guide member 34 forms not only the first guide surface 32 of the reverse guide passage 16 but also the lower guide surface 43 of the paper discharge path 23B. The recording sheet that has passed through the recording unit 24 is discharged downstream by a pair of discharge rollers 62 and a spur 63 while being supported by the lower guide surface 43 of the guide member 34.

  The first guide surface 33 is formed by the surface of the guide member 35 disposed inside the main body frame 53 and the surface of the flap 17 that is pivotally supported by the paper discharge tray 21. The guide member 34, the guide member 35, and the flap 17 are disposed to face each other at a predetermined interval. The first guide surface 32 and the second guide surface 33 extend obliquely downward from the downstream portion 36 of the transport path 23 toward the paper feed roller 25.

  In the present embodiment, the reversing guide path 16 is configured to return the recording paper onto the paper feed tray 20, but is not limited thereto. In short, it is sufficient for the reverse guide path 16 to be able to connect the downstream side portion 36 and the upstream side portion 37 of the transport path 23, and therefore, the recording sheet passes through the route other than the reverse guide passage 16 and is downstream. What is necessary is just to return to the upstream site | part 37 from the site | part 36. FIG.

  The flap 17 has a support shaft 115. The support shaft 115 is pivotally supported at the tip of the paper discharge tray 21 so as to be rotatable. Therefore, the flap 17 can be rotated around the support shaft 115. The flap 17 has a protruding portion 117 that protrudes obliquely downward from the center in the width direction of the paper feed tray 20 (perpendicular to the paper surface in FIG. 3) toward the bottom plate 113 of the paper feed tray 20. The protruding portion 117 extends to the bottom plate 113 in a state where no recording paper is present in the paper feed tray 20.

  The flap 17 rotates by its own weight or by a torsion coil spring (not shown) provided on the support shaft 115 in the direction indicated by the arrow 119 in FIG. Comes into contact with the uppermost recording sheet of the sheet feeding tray 20. Note that when the height of the uppermost recording sheet changes depending on the loading amount of the recording sheet in the sheet feeding tray 20, in this embodiment, the front end of the flap 17 is always in contact with the upper surface of the recording sheet regardless of the loading amount. It is configured as follows. Therefore, the recording paper loaded on the paper feed tray 20 always receives a downward pressing force from the flap 17. Since this pressing force acts on the recording paper, even if the leading end of the recording paper that has passed through the reverse guide passage 16 and is returned to the paper feed tray 20 is curled (curled back), the curl is flap 17. It is pressed down by.

  Next, the route switching unit 41 will be described with reference to FIG. FIG. 4 is an enlarged cross-sectional view showing the detailed configuration of the periphery of the route switching unit 41, (A) shows the route switching unit 41 moved to the discharge posture, and (B) shows The path switching unit 41 moved to the reverse posture is shown.

  The path switching unit 41 is disposed on the downstream side of the recording unit 24. Specifically, the path switching unit 41 is disposed downstream of the recording unit 24, that is, in the vicinity of the connection part between the paper discharge path 23 </ b> B and the reverse guide path 16. The path switching unit 41 includes a first roller 45 (an example of a driving roller of the present invention) and a second roller 46 (an example of a driven roller of the present invention), and a second roller 46, which are examples of a pair of feed rollers of the present invention. And an auxiliary roller 47 (an example of the auxiliary roller of the present invention) provided side by side.

  The first roller 45 and the second roller 46 sandwich the recording paper sent from the paper discharge roller 62 and the spur 63 and convey it in a predetermined direction. When the first roller 45 is rotated either forwardly or reversely, the recording paper that has passed through the recording unit 24 is conveyed further downstream (discharge tray 21 side) along the discharge path 23B. Alternatively, it is switched back in the transport process and transported toward the reverse guide path 16.

  The second roller 46 and the auxiliary roller 47 are attached to the frame 48. The frame 48 extends in the left-right direction (perpendicular to the plane of FIG. 4) of the multifunction machine 10. The cross-sectional shape of the frame 48 is generally L-shaped, thereby ensuring the required bending rigidity of the frame 48. The frame 48 extends in a direction along the paper discharge path 23B in a cross-sectional view, that is, in the conveyance direction of the recording paper conveyed through the paper discharge path 23B. In the present embodiment, the frame 48 is configured to be rotatable about the central shaft 52 of the first roller 45 by the drive mechanism 44, and the discharging posture shown in FIG. (Corresponding to the position) and a reverse posture shown in FIG. 4B. 4A, the auxiliary roller 47 is separated from the recording paper passing through the paper discharge path 23B, and the recording paper conveyed by the paper discharge roller 62 and the spur 63 passes through the paper discharge path 23B. The posture is such that the first roller 45 and the second roller 46 can pass through. 4B is an attitude capable of guiding the trailing edge of the recording sheet that has passed through the recording unit 24 to the inversion guide passage 16. The drive mechanism 44 of the frame 48 will be described later.

  The frame 48 includes eight integrated subframes 49 (see FIG. 7). Each sub-frame 49 is symmetrically arranged in the left-right direction with respect to the center of the multifunction machine 10. Each subframe 49 extends in the conveyance direction of the recording paper. Each subframe 49 pivotally supports one second roller 46 and auxiliary roller 47. Accordingly, the frame 48 includes eight second rollers 46 and auxiliary rollers 47, respectively. In the frame 48, the second rollers 46 and the auxiliary rollers 47 are arranged side by side in a direction perpendicular to the recording sheet conveyance direction, that is, in the width direction of the recording sheet.

  The second roller 46 and the auxiliary roller 47 are pivotally supported by support shafts 50 and 51 provided in each subframe 49 and are configured to be rotatable around the support shafts 50 and 51. In the subframe 49, the support shaft 50 is provided at the downstream end, and the support shaft 51 is provided at the upstream end. Therefore, the auxiliary roller 47 is disposed upstream of the second roller 46 by a predetermined distance. In the present embodiment, the second roller 46 and the auxiliary roller 47 are formed in a spur shape. The second roller 46 is biased downward by a spring (not shown) and is always elastically pressed against the first roller 45.

  The first roller 45 is connected to the LF motor 71 (see FIG. 10) via a required drive transmission mechanism, and is rotationally driven using the LF motor 71 as a drive source. That is, the first roller 45 is driven to rotate by receiving the driving force of the LF motor 71. The first roller 45 includes a center shaft 52, and the center shaft 52 is supported on the main body frame 53 side of the multifunction machine 10.

  A second roller 46 is disposed above the first roller 45. The second roller 46 is in contact with the first roller 45 and rotates following the first roller 45. The first roller 45 may be formed in a single elongated cylindrical shape, and a plurality of rollers may be disposed to face the second rollers 46, respectively. The first roller 45 is rotated forward or reverse by the LF motor 71. The recording paper conveyed from the recording unit 24 along the paper discharge path 23B is sandwiched between the first roller 45 and the second roller 46. In the present embodiment, the outer diameter of the first roller 45 is set slightly larger than the outer diameter of the paper discharge roller 62. That is, when both are driven at the same rotational speed, the peripheral speed of the first roller 45 is larger than the peripheral speed of the paper discharge roller 62. Therefore, when the recording paper is conveyed by both the paper discharge roller 62 and the first roller 45, the recording paper is always pulled in the conveyance direction.

  Here, with reference to FIG. 7 thru | or FIG. 9, the drive mechanism 44 of the path | route switching part 41 comprised as mentioned above is demonstrated. FIG. 7 is a perspective view of the path switching unit 41 and the drive mechanism 44. FIG. 8 is a view in the direction of arrow VIII shown in FIG. FIG. 9 is a view in the direction of arrow IX shown in FIG. The drive mechanism 44 rotates the path switching unit 41 between a discharge posture shown in FIG. 4A and a reverse posture shown in FIG. 4B.

  As shown in FIG. 7, the drive mechanism 44 is provided with a driven gear 54 provided on the central shaft 52, a drive gear 55 that meshes with the driven gear 54, and a cam 57 that is connected to the drive gear 55.

  The cam 57 is connected to one end of a rotary drive shaft 58 disposed in parallel with the extending direction of the frame 48. The rotary drive shaft 58 is driven using the LF motor 71 as a drive source. As shown in FIG. 9, the cam 57 is provided with a guide groove 59. The guide groove 59 is formed in an annular shape around the rotation drive shaft 58. Specifically, the guide groove 59 includes a small arc portion 69 and a large arc portion 70 centered on the rotation drive shaft 58, and a connection groove 72 that connects one end of the small arc portion 69 and one end of the large arc portion 70. A connecting groove 73 that connects the other end of the small arc portion 69 and the other end of the large arc portion 70 is provided.

  As will be described later, it is necessary to rotate the path switching unit 41 by rotating the cam 57 by the LF motor 71 while the recording sheet is stopped at the first stop position. Therefore, when the path switching unit 41 is rotated, the driving force of the LF motor 71 is configured not to be transmitted to the paper discharge roller 62 or the first roller 45 using a planetary gear or the like. Conversely, when the path switching unit 41 needs to hold the discharge posture (see FIG. 4A) or the reverse posture (see FIG. 4B), the planetary gear or the like is used to The driving force of the LF motor 71 is not transmitted to the cam 57 during the conveyance.

  As shown in FIGS. 7 and 8, the driven gear 54 includes a tooth portion 64 and a flange portion 65. The tooth portion 64 is configured as an involute gear centered on the central shaft 52. The tooth portion 64 is fitted into the central shaft 52 and can rotate around the central shaft 52. The flange portion 65 is formed integrally with the tooth portion 64 and is connected to the frame 48. Therefore, when the tooth portion 64 is rotated, the frame 48, the sub frame 49, the second roller 46, and the auxiliary roller 47 are integrally rotated about the central shaft 52.

  The drive gear 55 is rotatably supported on the support shaft 66. The support shaft 66 is provided on the main body frame 53. The drive gear 55 includes a tooth portion 67 and an arm 68. The tooth part 67 is configured as an involute gear centered on the support shaft 66 and meshes with the tooth part 64. A pin 56 shown in FIG. 9 protrudes from the arm 68. The pin 56 is fitted in the guide groove 59 and is slidable along the guide groove 59. As the tooth portion 67 rotates, the tooth portion 64 rotates. As a result, the frame 48, the sub-frame 49, the second roller 46, and the auxiliary roller 47 rotate integrally around the central shaft 52. In the present embodiment, when the pin 56 is located in the large arc portion 70, the path switching portion 41 is in the discharging posture (see FIG. 4A), and when the pin 56 is located in the small arc portion 69, the path switching portion 41 is placed. Is an inverted posture (see FIG. 4B).

  As shown in FIG. 9, when the cam 57 rotates, the pin 56 moves relatively along the guide groove 59, and in particular, when sliding along the connecting grooves 72, 73, the pin 56 moves to the cam 57. Will move in the radial direction. For this reason, when the cam 57 is rotated clockwise (in the direction of the arrow 82) in FIG. 9, the pin 56 sequentially moves to the large arc portion 70, the connecting groove 72, and the small arc portion 69.

  Therefore, the drive gear 55 rotates clockwise in FIG. As a result, the driven gear 54 rotates counterclockwise around the central axis 52 in FIG. As described above, since the driven gear 54 is connected to the frame 48, the rotation of the driven gear 54 causes the frame 48, the sub frame 49, the first roller 46, and the auxiliary roller 47 to be integrated around the central shaft 52. Rotate. If the cam 57 rotates in the reverse direction, naturally, the frame 48, the sub frame 49, the first roller 46, and the auxiliary roller 47 rotate integrally in the reverse direction around the central shaft 52.

  5 and 6 are schematic diagrams for explaining the operation of the route switching unit 41. FIG. 5 and 6, the guide member 34 is omitted. The posture change of the path switching unit 41 described below is achieved by switching the rotation direction of the LF motor 71 (see FIG. 10) and switching the first roller 45 to either forward rotation or reverse rotation. .

  In the present embodiment, when the first roller 45 is rotated in the forward direction (clockwise rotation in FIGS. 5 and 6) by the LF motor 71, the path switching unit 41 maintains its posture in the above-described discharge posture. Thus, the recording paper that has passed through the recording unit 24 is sent to the paper discharge tray 21 side (the right side in FIG. 5). When performing single-sided recording, the first roller 45 continues to rotate forward, so that the recording paper is sandwiched between the first roller 45 and the second roller 46 and conveyed downstream as shown in FIG. Then, the paper is discharged to the paper discharge tray 21.

  On the other hand, when performing double-sided recording, the recording paper is transported in a state where the recording paper is sandwiched between the first roller 45 and the second roller 46 and the rear end thereof is supported by the guide end 43A on the downstream side of the lower guide surface 43. Is paused. Thereafter, in a state where the recording paper is stopped, the path switching unit 41 goes through the pressing posture described later (corresponding to the second position of the present invention, see FIG. 12B) from the discharging posture (see FIG. 5). Then, it reciprocates so as to return to the discharge posture again. In the reciprocating process, the auxiliary roller 47 is immersed in the branch port 36 </ b> A and is disposed below the lower guide surface 43. As a result, the auxiliary roller 47 presses the recording paper in the paper discharge path 23 </ b> B downward, and retracts the rear end side of the recording paper below the lower guide surface 43.

  Thereafter, the recording paper is conveyed until the rear end passes through the guide end 43 </ b> A of the guide member 34. When the trailing edge of the recording paper passes through the guide end 43A, the recording paper is again paused. Then, the path switching unit 41 rotates in the direction of the arrow 29 to change the posture from the discharge posture (see FIG. 5) to the reverse posture (see FIG. 6). When the posture of the path switching unit 41 is changed from the discharge posture to the reverse posture, the rear end of the recording paper is bent downward, and the rear end of the recording paper is directed to the reverse guide path 16 side. Thereafter, the recording sheet is conveyed in the reverse direction, whereby the recording sheet is switched back, and is conveyed toward the feed roller 25 through the reverse guide path 16.

  In the present embodiment, when the first roller 45 is rotating forward, the driving force of the SF motor 74 (see FIG. 10) is transmitted to the paper feeding roller 25, and when the first roller 45 is rotating backward, the driving force is transmitted. The SF motor 74 is driven and controlled so as not to be transmitted to the paper feed roller 25. That is, the sheet feeding roller 25 does not rotate while the recording sheet is conveyed through the reverse guide path 16 by the first roller 45 or the like. Such a configuration can be realized by independently controlling the SF motor 74 that supplies driving force to the paper feed roller 25. Of course, when a drive transmission system in which the rollers such as the paper feed roller 25 and the conveyance roller 62 are driven by a common motor is used, the above operation can be realized by using a transmission switching mechanism such as a clutch or a planetary gear. it can.

  Next, the configuration of the control unit 84 of the multifunction machine 10 will be described with reference to FIG. FIG. 10 is a block diagram illustrating a configuration of the control unit 84 of the multifunction machine 10. The control unit 84 controls the overall operation of the multifunction machine 10, but a detailed description of the control of the scanner unit 12 and the recording unit 24 is omitted. In the present embodiment, the control unit 84 embodies the transport control means and the drive control means of the present invention.

  The control unit 84 is configured as a microcomputer mainly including a CPU 88, ROM 89, RAM 90, and EEPROM 91, and is connected to each unit via a bus 92.

  The ROM 89 stores a program for controlling various operations of the multifunction machine 10. For example, a control program for executing processing of each procedure (step) according to the flowchart shown in FIG. 11 is stored.

  The RAM 90 is used as a storage area or work area for temporarily recording various data used when the CPU 88 executes the program.

  The EEPROM 91 stores data, settings, flags, etc. that should be retained even after the power is turned off.

  The drive circuit 94 drives the LF motor 71 connected to the transport roller 60, the paper discharge roller 62, the first roller 45, and the SF motor 74 connected to the paper feed roller 25. The drive circuit 94 is provided with drivers for driving the LF motor 71 and the SF motor 74, and the LF motor 71 and the SF motor 74 are independently controlled. The drive circuit 94 receives the phase excitation signal output from the CPU 88 and generates an electrical signal for rotating the LF motor 71 and the SF motor 74. In response to the electrical signal, the LF motor 71 and the SF motor 74 rotate, and the rotational force of the LF motor 71 and the SF motor 74 is transferred via a known drive mechanism including a gear, a drive shaft, and the like. It is transmitted to the paper feed roller 25.

  In the multifunction machine 10 according to the present embodiment, the LF motor 71 is a drive source for transporting the recording paper positioned on the platen 42 and discharging the recorded recording paper to the paper discharge tray 21. Also, it serves as a drive source for driving the paper discharge roller 62 via a predetermined power transmission mechanism. Further, the LF motor 71 moves the path switching unit 41 from the discharging posture (see FIG. 4A) to the pressing posture (see FIG. 12B) via the rotation drive shaft 58 of the driving mechanism 44, a transmission gear (not shown), and the like. ) And a drive source for rotating until the reverse posture (see FIG. 4B).

  The bus 92 includes a rotary encoder that detects the amount of rotation of the registration sensor 102 for detecting the leading end position of the recording paper fed from the paper feed roller 25 to the curved path 23A, the conveyance roller 60 driven by the LF motor 71, and the like. 87, a rotary encoder 86 for detecting the rotation amount of the paper feed roller 25 driven by the SF motor 74 is connected. Based on the output signal of the registration sensor 102 and the encoder amount detected by the rotary encoders 86 and 87, the control unit 84 grasps the position of the leading or trailing edge of the recording paper in the transport path 23 and the transport amount of the recording paper.

  Next, with reference to FIGS. 12 to 14, an example of a procedure of control processing executed by the control unit 84 when double-sided image recording is performed in the printer unit 11 of the multifunction machine 10 using the flowchart of FIG. 11. explain. FIG. 11 is a flowchart illustrating a procedure of control processing executed by the control unit 84 of the multifunction machine 10. In the control processing of FIG. 11, description will be made assuming that an instruction for double-sided image recording is input. 12 to 14 are cross-sectional views showing the state of the recording paper during double-sided recording in chronological order.

  When an instruction to execute double-sided image recording is input, the CPU 88 of the control unit 84 drives and controls the SF motor 74 to drive the paper feed roller 25, whereby the recording paper is fed from the paper feed tray 20 in the direction of the arrow 14. (S1). The recording sheet is conveyed toward the downstream side in the curved path 23 </ b> A of the conveyance path 23. In the process of transporting the curved path 23 </ b> A, the recording paper is reversed so that the surface (back surface) opposite to the surface with which the paper feed roller 25 contacts is opposed to the nozzle forming surface of the recording head 39.

  When the recording paper reaches the conveyance roller 60 and the pinch roller 61, the recording paper is sandwiched by the conveyance roller 60 and the pinch roller 61, and the recording paper is conveyed onto the platen 42 by the conveyance roller 60 and the pinch roller 61. Then, image recording on the surface facing the recording head 39 is started (S2).

  The image recording on the surface is performed by intermittently transporting the recording paper by the transport roller 60 and the pinch roller 61, and when the recording paper is temporarily stopped in the intermittent transport process, the carriage 38 is slid from the recording head 39. This is done by ejecting ink droplets. Thereby, an image is recorded on the surface of the recording paper.

  When the recording paper reaches the paper discharge roller 62 and the spur 63, the recording paper is further conveyed to the downstream side by receiving the conveying force from the paper discharge roller 62 and the spur 63. The recording sheet conveyed by the sheet discharge roller 62 and the spur 63 is conveyed downstream in the sheet discharge path 23 </ b> B while being supported by the lower guide surface 43 of the guide member 34. When the leading edge of the recording paper reaches the first roller 45 and the second roller 46, the recording paper is sandwiched by the first roller 45 and the second roller 46 and further conveyed downstream. During this time, image recording on the surface of the recording paper is completed.

  When the image recording on the front surface is completed, the recording paper is stopped at the first stop position before the image recording is performed on the back surface. Specifically, as shown in FIG. 12A, the recording sheet is sandwiched between the first roller 45 and the second roller 46, and the rear end (upstream end) of the recording sheet is on the lower side. The recording paper is conveyed by the first roller 45 and the second roller 46 to the first stop position where the posture is supported by the guide end 43A on the downstream side of the guide surface 43 (corresponding to the first posture of the present invention). The driving of the first roller 45 and the second roller 46 is stopped at the first stop position (S3). Whether or not the recording sheet has reached the first stop position is acquired from the size information of the recording sheet input from the operation panel 40 or an externally connected personal computer, or from the registration sensor 102 or the rotary encoders 86 and 87. This can be determined based on the information, the path length from the paper feed tray 20 to the first stop position, and the like.

  Subsequently, in a state where the recording sheet is stopped at the first stop position, the path switching unit 41 goes through the pressing posture (see FIG. 12B) from the discharging posture (see FIG. 4A) again. It is continuously reciprocated so as to return to the discharging posture (S4). Here, the pressing posture is a posture arbitrarily set between the discharging posture and the reverse posture (see FIG. 4B), and as shown in FIG. 12B, the roller of the auxiliary roller 47 A part of the surface is immersed downward from the branch port 36 and is disposed below the lower guide surface 43. In the present embodiment, the pressing posture is set to an intermediate position between the discharging posture and the reverse posture. In this pressing posture, the auxiliary roller 47 presses the recording sheet below the lower guide surface 43 to bend the recording sheet in the width direction (direction perpendicular to the sheet surface of FIG. 12). The reciprocating movement of the path switching unit 41 is performed, for example, by rotating the LF motor 71 in one direction to move the pin 56 of the drive mechanism 44 from the large arc portion 70 to the middle of the connecting groove 72 (or connecting groove 73). And then, the LF motor 71 is driven to rotate in the reverse direction without providing a substantial stop time, and the pin 56 is returned to the large arc portion 70 again.

  As a result of the reciprocal movement, as shown in FIG. 13C, the rear end side of the recording paper is curled in a curved shape.

  When the recording sheet is pressed downward by the auxiliary roller 47 and the recording sheet is bent downward, an upward repulsive force is generated on the recording sheet to return to the original shape. This repulsive force is proportional to the rigidity (strength of the paper) of the recording paper, and the greater the rigidity, the smaller the smaller. As described above, in the present embodiment, the path switching unit 41 does not substantially stop in the pressing posture. Therefore, the degree of wrinkling of the recording paper is strongly influenced by the rigidity of the recording paper.

  For example, when a relatively thin and low-rigidity recording sheet such as tracing paper is pressed by the auxiliary roller 47 in the reciprocating movement process, the repulsive force is small, and therefore, it is indicated by a broken line in FIG. As described above, the recording paper is greatly glazed. A thin recording sheet tends to generate large cockling when an image is recorded. Therefore, such a recording sheet can be rubbed large so that the cockling generated on the recording sheet can be suitably eliminated. it can.

  On the other hand, even if a relatively thick and stiff recording paper such as a postcard or glossy paper is pressed by the auxiliary roller 47 in the reciprocating movement process, the repulsive force is large, and therefore, it is indicated by a solid line in FIG. As you can see, only a small amount of paper is available. Thick recording paper produces only minute cockling even when an image is recorded. For this reason, a small brazing is performed on a thick and stiff recording sheet, so that excessive brazing is prevented and cockling generated on the recording sheet can be preferably eliminated.

  In other words, in the printer unit 11 of the present embodiment, the recording paper in which cockling has occurred due to the recording of an image on the surface of various recording papers having different rigidity is corrected substantially uniformly regardless of the rigidity. can do.

  When the path switching unit 41 is returned to the original posture, that is, the discharge posture, the route switching unit 41 is set in advance in a state in which the path switching unit 41 maintains the discharge posture and the posture in which the recording sheet is in the first stop position. The CPU 88 determines whether or not the held time has elapsed (S5). Such determination processing is performed in order to stop the recording sheet for the holding time. The holding time is provided as a time for drying the ink image recorded on the surface. This holding time is a time determined according to, for example, the amount of ink discharged onto the surface. The ink ejection amount can be predicted from the number of ejections by the recording head. The holding time corresponding to the ink ejection amount is stored in the EEPROM 91 or the like.

  If it is determined that the holding time has passed (Yes in S5), then the CPU 88 causes the LF motor 71 to be rotationally driven again, whereby the recording paper is conveyed (re-conveyed) again (S6). Then, the recording sheet is conveyed to the second stop position where the trailing end of the recording sheet passes through the guide end 43A of the guide member 34 and reaches the branch port 36A (corresponding to the second attitude of the present invention). Then, the recording paper is temporarily stopped again at the second stop position (S7).

  Subsequently, the path switching unit 41 is driven so as to change the path switching unit 41 in the discharge attitude to the reverse attitude (S8). When the path switching unit 41 is changed from the discharging posture to the reverse posture, the path switching unit 41 is rotated about the central axis 52 of the first roller 45 until the auxiliary roller 47 contacts the guide surface 33 of the guide member 35. To do. As a result, the trailing edge of the recording sheet is pressed against the reverse guide path 16 by the auxiliary roller 47. Then, the rear end of the recording sheet enters the reverse guide path 16 as shown in FIG.

  Then, the first roller 45 and the second roller 46 are driven in reverse (S9). As a result, the recording paper is switched back and conveyed through the reverse guide path 16 toward the paper feed roller 25. Thereafter, when the recording paper reaches the paper feed roller 25, the paper feed roller 25 is driven to convey the recording paper again toward the recording unit 24 (S10). Thereby, in the conveyance path 23, the recording paper is reversed so that the surface (back surface) opposite to the surface (front surface) with which the paper feed roller 25 contacts is opposed to the nozzle formation of the recording head 39. Thereafter, image recording is started on the back surface by the recording head 39 (S11).

  Then, before the leading edge (the leading edge of the back surface) of the storage sheet 103 enters the path switching unit 41, the path switching unit 41 is driven so that the path switching unit 41 is changed from the inverted posture to the discharging posture again (S12). ). Thereafter, image recording on the back surface of the recording paper is completed, and the recording paper on which images are recorded on both sides is conveyed downstream by the first roller 45 and the second roller 46. At this time, the first roller 45 and the second roller 46 rotate forward, and the recording paper is discharged to the paper discharge tray 21 (S13).

  As described above, in the present embodiment, in step S4 described above, the path switching unit 41 does not substantially temporarily stop, and the pressing posture (see FIG. 12B) is changed from the discharging posture (see FIG. 4A). ), The paper is continuously reciprocated so as to return to the discharge posture again. Therefore, even when a thin and low-rigidity recording paper is conveyed, a thick and high-rigidity recording paper is conveyed. Even in such a case, it is possible to apply a brazing to the recording paper according to the degree of cockling that occurs on each recording paper.

  In the above-described embodiment, in steps S6 to S8, the recording sheet is transported to the second stop position, the recording sheet is stopped at the second stop position, and in this state, the path switching unit is driven to the determination posture. However, instead of transporting the recording paper to the second stop position, the path switching unit 41 may be driven from the ejection posture to the reverse posture with the recording paper in the first position. In other words, after the holding time has elapsed (Yes in S5), the path switching unit 41 is ejected while the recording paper is in the first stop position (see FIG. 13C) without being conveyed again. You may drive to a reverse attitude | position through a press attitude | position (refer FIG. 12 (B)) from FIG. 4 (A)). In this case, the rear end of the recording sheet is bent in the process of changing the path switching unit 41 from the pressing posture to the reverse posture, so that it is not supported by the guide end 43A, as shown in FIG. , Directed to the reversal guide passage 16. By driving the path switching unit 41 in this way, the process of transporting the recording paper to the second stop position can be omitted, and as a result, the transport time of the recording paper can be shortened.

  In the above-described embodiment, the intermediate posture between the discharge posture and the reverse posture is exemplified as the pressing posture of the path switching unit 41, but the pressing posture is not limited to such a posture. The position of the pressing posture may be appropriately set at a position where the recording sheet can be curved and deformed by a desired amount when the auxiliary roller 47 presses the recording sheet downward. Therefore, any posture can be used as long as the auxiliary roller 47 can bend and deform the recording paper. For example, the pressing posture can be the same as the reverse posture.

  In the above-described embodiment, the moving member of the present invention is realized by the path switching unit 41, and the retracting unit of the present invention is the guide member 34, the first roller 45 and the second roller 46, and the branch port 36A in the downstream portion 36. However, the present invention is of course not limited to such a configuration. For example, as a modification of the present invention, a mechanism shown in the schematic diagram of FIG. 15 can be considered. FIG. 15 is a schematic diagram schematically showing a modification of the present invention. In this modification, a rotating member 130 (an example of a moving member of the present invention) is provided in the upper guide 131 of the paper discharge path 23B, and a recess 137 (in the present invention of the present invention) is provided in the lower guide 132 of the paper discharge path 23B. An example of a retreat unit is provided. The rotating member 130 is supported so as to be rotatable about a support shaft 134 and extends from the support shaft 134 toward the paper discharge path 23B. The extending end of the rotating member 130 is a contact portion 135 that contacts the recording paper. The support shaft 134 is connected to a drive source such as a motor, and the rotation is controlled by the control unit 84. Until the rear end of the recording sheet 136 reaches the vicinity of the upstream end portion 137A of the recessed portion 137, the rotating member 130 maintains the discharging posture shown in FIG. When the rear end of the recording paper 136 reaches the vicinity of the upstream end 137A of the recessed portion 137 (see FIG. 15A), the recording paper 136 is stopped. Thereafter, when the rotation member 130 is rotated in the direction of the arrow 138 and the contact portion 135 is in contact with the recording paper 136 to bend the recording paper 136 (see FIG. 15B), the posture is reached. Without being stopped, it is immediately returned to the original discharge posture. Even with the rotating member 130 and the recessed portion 137 provided in this way, the recording paper can be brazed according to the degree of cockling that occurs on the recording paper, regardless of the rigidity of the recording paper.

  In the modified example, a configuration in which the recessed portion 137 is provided in the upper guide 131 and the rotating member 130 is provided in the lower guide 132 may be employed. Furthermore, in place of the rotating member 130, it is supported so as to be linearly movable in a direction crossing the paper discharge path 23B, and is configured to continuously reciprocate between the discharge posture and the pressing posture. It is also possible to apply different moving members.

FIG. 1 is an external perspective view of a multifunction machine 10 according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing the structure of the printer unit 11. FIG. 3 is a partially enlarged sectional view of the printer unit 11. FIG. 4 is an enlarged cross-sectional view showing a detailed configuration around the route switching unit 41. FIG. 5 is a schematic diagram for explaining the operation of the route switching unit 41. FIG. 6 is a schematic diagram for explaining the operation of the path switching unit 41. FIG. 7 is a perspective view of the path switching unit 41 and the drive mechanism 44. FIG. 8 is a view in the direction of arrow VIII shown in FIG. FIG. 9 is a view in the direction of arrow IX shown in FIG. FIG. 10 is a block diagram illustrating a configuration of the control unit 84 of the multifunction machine 10. FIG. 11 is a flowchart illustrating a procedure of control processing executed by the control unit 84 of the multifunction machine 10. FIG. 12 is a cross-sectional view showing the state of the recording paper during double-sided recording in chronological order. FIG. 13 is a cross-sectional view showing the state of the recording paper during double-sided recording in chronological order. FIG. 14 is a cross-sectional view showing the state of the recording paper during double-sided recording in chronological order. FIG. 15 is a schematic diagram schematically showing a modification of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Multifunction machine 11 ... Printer part 16 ... Reverse guide path 20 ... Paper feed tray 21 ... Paper discharge tray 24 ... Conveyance path 24A ... Curved path 24B ... Discharge Paper path 25... Paper feed roller 36... Downstream portion 36 A... Branch opening 39... Recording head 41. ..Second roller 47 ... auxiliary roller 84 ... control unit

Claims (10)

An image recording apparatus comprising a recording head for recording an image by ejecting ink onto a recording sheet, and capable of recording an image on both the first surface and the second surface of the recording sheet by the recording head,
A retracting portion provided in a transport path downstream in the transport direction from the recording head, and retracting a part of the recording paper to the outside of the transport guide surface of the transport path;
A movable member movable between a first position where the recording paper can pass through the conveyance path and a second position where the recording paper is immersed in the retracting portion;
After the image is recorded on the first surface of the recording paper, before the image is recorded on the second surface by the recording head, the recording paper is in the first posture supported by the retracting portion. Conveyance control means for stopping
Drive control means for continuously moving the moving member from the first position to the first position again through the second position in a state where the recording paper is stopped in the first posture by the conveyance control means; An image recording apparatus comprising: A feeding roller that contacts the recording paper loaded on the tray and feeds the recording paper;
A first conveyance path that is formed in a curved shape between the feeding roller and the recording head and guides the recording paper so that a surface opposite to the surface on which the feeding roller abuts faces the recording head When,
A support member that is provided downstream of the recording head in the transport direction and supports the recording paper that has passed through the recording head;
A second conveyance path branched from the downstream side in the conveyance direction than the support member and connected to the upstream side in the conveyance direction of the first conveyance path;
It is provided downstream of the support member in the transport direction, and is configured to be capable of normal rotation and reverse rotation. The recording paper that has passed through the recording head is sandwiched and rotated forward to convey the recording paper to the outside or A pair of feed rollers that switch back the recording paper by reverse rotation and convey it to the second conveying path;
The retracting portion is configured by the support member and the pair of feed rollers, and has a branch port that is formed between the support member and the pair of feed rollers and guides the recording sheet to the second transport path,
The conveyance control unit stops the recording sheet in the first posture in which the end on the downstream side in the conveyance direction of the recording sheet is sandwiched by the pair of feed rollers and the end on the upstream side in the conveyance direction is supported by the support member. Let
The said moving member presses the part located between the said supporting member and said pair of feed roller in the recording paper stopped by the said conveyance control means in the said 2nd position to the said branch port side. The image recording apparatus described.   The moving member has a third position that can guide the upstream end of the recording sheet, which is sandwiched between the pair of feed rollers, from the first position to the second conveying path through the second position. The image recording apparatus according to claim 2, which is supported so as to be movable. The conveyance control unit performs the recording until the end on the upstream side in the conveyance direction of the recording paper reaches the second posture after the moving member is returned to the first position by the drive control unit. Transport the paper and stop the recording paper in the second posture,
The image recording apparatus according to claim 3, wherein the drive control unit moves the moving member from the first position to the third position in a state where the recording paper is stopped in the second posture by the conveyance control unit. .   The drive control means continuously moves the moving member from the first position to the first position again through the second position with the recording paper stopped in the first posture by the conveyance control means. The image recording apparatus according to claim 3, wherein the moving member is moved from the first position to the third position after being moved.   The image recording apparatus according to claim 1, wherein the second position is a position where the moving member presses the first surface of the recording sheet to bend and deform the recording sheet by a predetermined amount. The moving member is
7. The image recording apparatus according to claim 1, wherein the image recording apparatus is supported so as to be rotatable about one end side as a rotation center, and the other end side can be displaced from the first position to the second position in accordance with the rotation operation. . The pair of feed rollers includes a driving roller that rotates by receiving a driving force and a driven roller that rotates by following the driving roller,
3. The moving member is supported by the one end side so that the driven roller is pivotally supported so as to be pivoted upstream in the conveying direction and pivotable about a rotation shaft of the driving roller. 8. The image recording apparatus according to any one of items 7.   The image recording apparatus according to claim 7 or 8, wherein an auxiliary roller capable of contacting a recording sheet is rotatably supported on the other end side of the moving member. A recording head for recording an image by ejecting ink onto the recording paper and a transport path downstream of the recording head in the transport direction, and a part of the recording paper is retracted outside the transport guide surface of the transport path. And a moving member movable between a first position where the recording paper can pass through the conveyance path and a second position where the recording paper is inserted into the retracting section. A recording paper conveyance control method applied to an image recording apparatus capable of recording an image on both sides of a first side and a second side,
After the image is recorded on the first surface of the recording paper, before the image is recorded on the second surface by the recording head, the recording paper is in the first posture supported by the retracting portion. A first step of stopping
A second step of continuously moving the moving member from the first position to the first position again through the second position with the recording paper stopped in the first posture by the first step; A recording paper conveyance control method comprising:

Images