JP5621614B2 - Image recording device - Google Patents

Description

  The present invention relates to an image recording apparatus capable of conveying a sheet along a conveyance path and recording an image on the sheet.

  Conventionally, an image recording apparatus that records an image on a sheet based on an input signal is known. As an image recording method of such an image recording apparatus, for example, there are an ink jet recording method and an electrophotographic method.

  The sheet is conveyed by being sandwiched between a pair of rollers provided inside the image recording apparatus. In this case, at the moment when the trailing edge of the sheet comes out of the roller pair, a force is applied to the sheet in the conveying direction. This may cause an error in the sheet conveyance distance. In order to prevent such a problem, in the recording apparatus disclosed in Patent Document 1, the two rollers constituting the roller pair are separated from each other immediately before the trailing edge of the sheet comes out of the roller pair.

  In view of recent demands for downsizing and cost reduction of image recording apparatuses, it is preferable that the number of motors mounted on the image recording apparatus is small. For example, in the image recording apparatus disclosed in Patent Document 2, a switching gear that is slidable in the thrust direction of the driving gear while meshing with a driving gear that is driven and transmitted from the motor is disposed, and is arranged at each sliding position of the switching gear. Correspondingly, a plurality of transmission gears for driving transmission to each mechanism are arranged. The switching gear is slid by being pushed by a slidable carriage that forms a part of the recording unit.

Japanese Patent Laid-Open No. 10-26851 JP 2007-90800 A

  When the structure adopted in the image recording apparatus disclosed in Patent Document 2 is applied to the recording apparatus disclosed in Patent Document 1, a mechanism for separating two rollers constituting a roller pair includes a plurality of transmission gears. Drive transmitted by one of them. In this case, the following problems occur.

  In order to drive the mechanism that separates the two rollers constituting the roller pair, the switching gear needs to be pushed by the carriage and slid to a predetermined position. Further, when the switching gear slid by the carriage is meshed with the transmission gear that has not been meshed so far, the switching gear needs to repeatedly execute forward and reverse rotation of a small amount of rotation. This is because the switching gear is disconnected from the transmission gear meshed before switching and the switching gear meshes with the newly meshed transmission gear smoothly.

  From the above, in order to drive the mechanism, it is necessary to execute forward / reverse rotation of the switching gear in addition to the carriage slide, which takes time. As a result, the total time from the start of feeding a sheet from a tray or the like in which the sheet is stored until the image is recorded on the sheet and the sheet is discharged is determined by the forward / reverse rotation of the switching gear. It will take longer to run.

  The present invention has been made in view of the above problems, and its object is to be sandwiched between a pair of rollers without significantly increasing the time from the start of sheet feeding until it is discharged after image recording. It is an object of the present invention to provide an image recording apparatus capable of preparing a posture for separating two rollers constituting a roller pair before the trailing edge of the sheet comes out of the roller pair.

(1) The image recording apparatus according to the present invention includes a placement unit on which a sheet can be placed, a first conveyance path through which the sheet is guided, and a sheet placed on the placement unit to the first conveyance path. A feeding roller that feeds out, a driving roller and a driven roller; a conveying unit that holds the sheet fed to the first conveying path by the feeding roller and conveys the sheet in a first direction; and A contact / separation mechanism for changing the posture to a first posture in which the driven roller and the driving roller are in contact with each other and a second posture in which the driven roller and the driving roller are separated from each other; A first detection unit that detects a front end and a rear end of the sheet conveyed in the first direction and outputs a detection signal; and on the downstream side in the first direction from the conveyance unit, Perpendicular to the first direction and along the image recording surface of the sheet A carriage that can reciprocate in the second direction, and a recording head that is mounted on the carriage and that records an image on an image recording surface by ejecting ink droplets toward a sheet conveyed through the first conveyance path. A first motor that applies a driving force to the carriage, a second motor that applies a driving force to the driving roller, a third motor that applies a driving force to the feeding roller and the contact / separation mechanism, and the carriage A drive transmission switching mechanism that selectively switches transmission of the driving force of the third motor to the feed roller or the contact / separation mechanism based on the movement of the first motor, the first motor, the second motor, and the third motor. And a control unit for controlling the driving of each. The drive transmission switching mechanism is meshed with the first gear which is driven and transmitted from the third motor and rotated with the second direction as an axial direction, and the first gear with the second direction as an axial direction, When the carriage is in contact with the second gear that can move to at least the first position and the second position along the second direction while maintaining meshing with the first gear, the carriage can move in the second direction. And at least a third position where the second gear can be held in the first position and a fourth position where the second gear can be held in the second position by contacting the second gear. a switching lever which can be moved, the biasing member urges the second gear from said second position to said first position, and a third gear that the second gear meshes with the first position Mesh with the second gear in the second position 4 gears, a first transmission unit for transmitting the driving force of the third motor from the third gear to the feeding roller, and a driving force of the third motor from the fourth gear to the contact / separation mechanism. A second transmission unit. The control unit drives the third motor to drive the feeding roller, and then determines the front end position and the rear end position of the sheet based on the detection signal of the first detection unit. The first motor is driven to move the switching lever from the third position to the fourth position during a period when the sheet passes through the conveying unit and the trailing edge of the sheet does not pass through the conveying unit. The forward drive and the reverse drive of the third motor are alternately executed at least once.

  As the switching lever is moved from the third position to the fourth position, the second gear is moved from the first position to the second position. Thereafter, the third motor alternately performs forward rotation and reverse rotation at least once, so that the separation of the second gear from the third gear and the engagement of the second gear with the fourth gear are completed. As described above, the switching lever is moved from the third position to the fourth position, and the third motor is driven forward / reversely, so that the drive transmission from the third motor to the contact / separation mechanism is possible.

  According to this configuration, the movement of the switching lever and the forward / reverse driving of the third motor are executed in a period in which the leading edge of the sheet passes through the conveyance unit and the trailing edge of the sheet does not pass through the conveyance unit. . During the period, the sheet is conveyed by the conveyance unit. That is, even when the movement of the switching lever and the forward / reverse rotation driving of the third motor are performed during the period, the time from the start of feeding the sheet from the placement unit to the ejection through the image recording is as follows: It doesn't get much longer.

  (2) The control unit extends the movement of the carriage in the second direction for image recording on the sheet by the recording head, thereby moving the switching lever from the third position to the fourth position. The forward rotation drive and the reverse rotation drive of the third motor are alternately executed at least once.

  According to this configuration, the movement of the carriage for moving the second gear to the second position can be executed only by extending the movement distance of the carriage for recording an image on the sheet.

  (3) The control unit drives the third motor on the condition that the rear end of the sheet has passed the first detection unit, and moves the conveyance unit from the first posture to the second posture. Change.

  According to this configuration, the third motor is driven on the condition that the rear end of the sheet has passed through the first detection unit provided on the upstream side in the first direction from the conveyance unit, and the conveyance unit is the first. The posture is changed from the posture to the second posture. Therefore, the driven roller and the driving roller can be separated before the trailing edge of the sheet passes through the conveyance unit.

  (4) The control unit is after the switching lever has been moved to the fourth position, after the trailing edge of the sheet has passed the conveyance unit, and image recording on the sheet by the recording head. Driving the third motor from the second posture to the first posture by driving the third motor for a predetermined period before stopping, and then driving the first motor. Then, the switching lever is moved from the fourth position to the third position, and the forward driving and the reverse driving of the third motor are alternately executed at least once.

  When the switching lever is moved from the fourth position to the third position, the second gear is moved from the second position to the first position. As a result, drive transmission from the third motor to the feed roller is possible. Thus, the feeding roller can send the sheet to the first conveyance path only by the operation of driving the third motor. That is, according to this configuration, the operation of feeding the next sheet on which an image is recorded from the placement unit can be quickly executed.

  (5) The image recording apparatus of the present invention is branched from the first transport path at a branch position downstream of the recording head in the first direction, and upstream of the first direction of the first detection unit. And a second conveyance path that is guided in a third direction from the branching position toward the merging position, and is provided in the second conveyance path. A conveying roller that conveys the sheet in the third direction along the second conveying path, and a third transmission unit that transmits the driving force of the third motor from the third gear to the conveying roller. In addition.

  When the switching lever is moved from the fourth position to the third position, the second gear is moved from the second position to the first position. As a result, the drive transmission from the third motor to the transport roller is possible. Accordingly, the conveyance roller can convey the sheet along the second conveyance path only by the operation of driving the third motor. That is, according to this configuration, the operation of transporting the image-recorded sheet to the second transport path can be quickly executed.

  (6) The control unit drives the first motor to switch the switching lever during a period in which the leading edge of the sheet has passed the conveyance unit and has not reached the start position of image recording by the recording head. Is moved from the third position to the fourth position, and the forward rotation drive and the reverse rotation drive of the third motor are alternately executed at least once.

  Normally, if the sheet is jammed in the apparatus during image recording on the sheet, the carriage is stopped. As a result, the carriage cannot move the switching lever. However, according to this configuration, the switching lever is moved to the fourth position by the carriage before the image recording on the sheet is started. Thereby, the second gear is moved to the second position. Accordingly, when the sheet is jammed in the apparatus during image recording on the sheet, the driven roller and the driving roller can be separated by driving the third motor. As a result, even when the sheet is jammed while being sandwiched between the driving roller and the driven roller, the sheet can be easily taken out from the apparatus.

  (7) The controller drives the third motor on the condition that the sheet is jammed in the first conveyance path after moving the switching lever to the fourth position, and the conveyance unit And changing the position of the unit from the first posture to the second posture.

  When it is determined that the sheet is jammed, the control unit drives the third motor. As a result, the driven roller and the drive roller are separated from each other. That is, according to this configuration, the separation between the driven roller and the driving roller can be automatically executed in a necessary situation.

  (8) The image recording apparatus of the present invention is provided with a guide surface that partitions the outside of the first transport path, and a third posture that exposes at least a part of the first transport path to the outside of the apparatus, and A guide member that shields at least a part of the first conveyance path from the outside of the apparatus and can change the posture to a fourth posture in which the sheet can be guided by the guide surface, and a second detection unit that detects the posture of the guide member And further. The controller controls the third motor on the condition that the second detection unit detects that the guide member is in the third posture after moving the switching lever to the fourth position. Driven to change the posture of the transport unit from the first posture to the second posture.

  When the sheet is jammed in the apparatus, the user can change the posture of the guide member to the third position and take out the sheet from the apparatus. According to this configuration, the control unit drives the third motor on condition that the guide member is in the third posture. As a result, the driven roller and the driving roller are separated from each other. That is, according to this configuration, the separation between the driven roller and the driving roller can be automatically executed in a necessary situation.

  According to the present invention, the movement of the switching lever and the forward / reverse driving of the third motor are executed in a period in which the leading edge of the sheet passes through the conveyance unit and the trailing edge of the sheet does not pass through the conveyance unit. Even in this case, the time from the start of sheet feeding from the loading unit to the ejection after image recording is not significantly increased. In other words, according to the present invention, before the trailing edge of the sheet held by the conveyance unit comes out of the conveyance unit without significantly increasing the time from the start of sheet feeding until it is discharged after image recording. It is possible to prepare a posture for separating the two rollers constituting the transport unit.

FIG. 1 is a perspective view of the multifunction machine 10. FIG. 2 is a longitudinal sectional view schematically showing the internal structure of the printer unit 11. FIG. 3 is a rear view schematically showing the drive transmission switching mechanism 50, the conveyance unit 59, and the contact / separation mechanism 90. 4A and 4B are diagrams for explaining the operation of the drive transmission switching mechanism 50 and the contact / separation mechanism 90. FIG. 4A is a plan view of the switching lever 55, and FIG. A left side view schematically showing the planet gear 157 of the second transmission unit 57 in the case of the first posture is shown, and (C) of the contact / separation mechanism 90 in the case where the transport unit 59 is in the first posture. A left side view schematically showing the eccentric cam 160 is shown, and (D) is a left side view schematically showing the planet gear 157 of the second transmission portion 57 when the transport portion 59 is in the second posture. FIG. 9E shows a left side view schematically showing the eccentric cam 160 of the contact / separation mechanism 90 when the transport section 59 is in the second posture. FIG. 5 is a right side view schematically showing the first transmission unit 27 and the third transmission unit 74. FIG. 6 is a block diagram illustrating a configuration of the control unit 130. FIG. 7 is a flowchart for explaining processing by the control unit 130. FIG. 8 is a flowchart for explaining processing by the control unit 130. FIG. 9 is a flowchart for explaining processing by the control unit 130 in the first modification. FIG. 10 is a flowchart for explaining processing by the control unit 130 in the second modification.

  Hereinafter, 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. Further, in the following description, the progression from the start point to the end point in consideration of the arrow in the vector is expressed as “direction”, and the traffic on the line connecting the start point and the end point without considering the arrow in the vector is referred to as “direction”. Expressed. In the following description, the vertical direction 7 is defined with reference to the state in which the multifunction machine 10 is installed (the state in FIG. 1), and the side on which the opening 13 is provided is the front side (front side). A front-rear direction 8 is defined, and a left-right direction 9 is defined when the multifunction machine 10 is viewed from the front side (front side).

[Multifunction machine 10]
As shown in FIG. 1, a multifunction machine 10 as an example of an image recording apparatus of the present invention is formed in a generally thin rectangular parallelepiped, and is provided with a printer unit 11 of an ink jet recording system in the lower part. The multifunction machine 10 has various functions such as a facsimile function and a print function. The print function has a double-sided image recording function for recording images on both sides of the recording paper. In this embodiment, the multifunction device 10 has a double-sided image recording function, but the multifunction device 10 may have only a single-sided image recording function.

  The printer unit 11 has a housing 14 having an opening 13 formed in the front. Further, a paper feed tray 20 and a paper discharge tray 21 (see FIG. 2, an example of the placement unit of the present invention) on which recording papers of various sizes (an example of the sheet of the present invention) can be placed are provided in the front-rear direction from the opening 13. 8 can be inserted and removed.

  An operation panel 17 is provided at the upper front of the multifunction machine 10. The operation panel 17 is a device for operating the multifunction machine 10. The multifunction machine 10 operates based on an operation input from the operation panel 17.

  As shown in FIG. 2, the printer unit 11 is provided above the paper feed tray 20 and a paper feed unit 15 that picks up and feeds recording paper from the paper feed tray 20. An ink jet recording type recording unit 24 that discharges ink droplets onto a fed recording sheet and records an image on the recording sheet, a path switching unit 41, and the like are provided.

[Paper Feeder 15]
As shown in FIG. 2, the paper feed unit 15 is provided above the paper feed tray 20 and below the recording unit 24. The paper feed unit 15 includes a feed roller 25 (an example of the feed roller of the present invention), a paper feed arm 26, and a drive transmission mechanism 27. The feed roller 25 is pivotally supported at the tip of the paper feed arm 26. The paper feed arm 26 rotates in the direction of an arrow 29 about a shaft 28 provided at the base end. As a result, the feed roller 25 can be brought into contact with and separated from the paper feed tray 20. That is, the feeding roller 25 can abut on the recording paper placed on the paper feed tray 20.

  The feed roller 25 is fed by a first transmission section 27 (an example of the first transmission section of the present invention, see FIG. 3), which will be described later, and a feed motor 70 (an example of the third motor of the present invention, see FIG. 6). The drive force is transmitted and rotates. That is, the paper feeding motor 70 applies a driving force to the feeding roller 25. The paper feed motor 70 also applies a driving force to the contact / separation mechanism 90 (see FIG. 3) described later. The feeding roller 25 is in contact with the uppermost recording paper among the recording papers stacked on the paper feed tray 20 and separates the recording paper from the other recording papers as will be described below. It sends out to the curved path 65A.

[First transport path 65]
As shown in FIG. 2, a first conveyance path 65 (in the present invention) extends from the front end (rear end) of the paper feed tray 20 to the paper discharge tray 21 through the recording unit 24. An example of a first conveyance path) is formed. The first transport path 65 includes a curved path 65A formed between the leading end of the paper feed tray 20 and the first transport roller 60, and a paper discharge formed between the first transport roller 60 and the paper discharge tray 21. It is divided into a road 65B.

  The curved path 65 </ b> A is a curved path extending from the vicinity of the upper end of the separation inclined plate 22 provided in the paper feed tray 20 to the recording unit 24. The curved path 65 </ b> A is generally formed in an arc shape centering on the inside of the printer unit 11. The recording paper fed from the paper feed tray 20 by the feeding roller 25 is attached to the first conveyance direction (the dashed line in FIG. 2) along the curved path 65A along the conveyance direction (the direction indicated by the dashed line in FIG. 2). The recording paper is curved in the direction of the arrow indicated, which corresponds to the first direction of the present invention, and is formed by the first conveying roller 60 (an example of the driving roller of the present invention) and the pinch roller 61 (an example of the driven roller of the present invention). To the clamping position. The curved path 65A is partitioned by an outer guide member 18 (an example of the guide member of the present invention) and an inner guide member 19 that face each other with a predetermined interval therebetween. Note that each of the outer guide member 18 and the inner guide member 19 and guide members 31, 32, 82, and 83, which will be described later, extend in the direction perpendicular to the plane of FIG. 2 (the left-right direction 9 in FIG. 1). .

  The paper discharge path 65 </ b> B is a linear path that extends from the position where the recording paper is held by the first transport roller 60 and the pinch roller 61 to the paper discharge tray 21. The recording paper is guided through the paper discharge path 65B in the first transport direction. The paper discharge path 65B is defined by a platen 42 that can support the recording unit 24 and the recording paper that are opposed to each other at a predetermined interval at a location where the recording unit 24 is provided. In addition, the paper discharge path 65B is partitioned by an upper guide member 82 and a lower guide member 83 that face each other at a predetermined interval at a location where the recording unit 24 is not provided.

  A branch position 36 (an example of a branch position according to the present invention) exists downstream of the recording unit 24 in the first transport direction and downstream of the second transport roller 62 described later in the first transport direction. The recording paper conveyed through the paper discharge path 65B is switched back downstream of the branch position 36 during double-sided image recording, and is directed to a second conveyance path 67 (an example of the second conveyance path of the present invention) described later. Be transported.

[Recording unit 24]
As shown in FIG. 2, the recording unit 24 is provided on the downstream side of the first transport roller 60 in the first transport direction in the paper discharge path 65B. The recording unit 24 is provided on the upper side of the paper discharge path 65B. As shown in FIG. 2, the recording unit 24 is mounted with a recording head 38 (an example of the recording head of the present invention), and is an image of a recording sheet that crosses the first transport direction and is transported through the paper discharge path 65B. A carriage 40 (an example of the carriage of the present invention) is provided that can reciprocate in the left-right direction 9 (corresponding to the second direction of the present invention) along the recording surface.

  The carriage 40 is supported by, for example, two guide rails (not shown) extending in the left-right direction 9 inside the printer unit 11. The two guide rails are arranged at a predetermined interval in the front-rear direction 8. The carriage 40 is disposed so as to straddle the two guide rails. As a result, the carriage 40 can slide in the left-right direction 9 on the two guide rails. A belt drive mechanism (not shown) is disposed on the upper surface of the guide rail. The belt constituting the belt driving mechanism is connected to the carriage 40. When the driving force is transmitted from the carriage driving motor 103 (see FIG. 6, an example of the first motor of the present invention) to the belt driving mechanism, the carriage 40 is slid in the left-right direction 9. That is, the carriage drive motor 103 applies a driving force to the carriage 40.

  As shown in FIG. 2, the recording head 38 is exposed on the lower surface side of the carriage 40. The recording head 38 is supplied with inks of cyan (C), magenta (M), yellow (Y), and black (Bk) from an ink cartridge (not shown) through an ink tube (not shown). A plurality of nozzles (not shown) are formed on the nozzle surface on the lower surface side of the recording head 38. Each nozzle is provided for each color ink of CMYBk. Each color ink is ejected from each nozzle as a fine ink droplet.

  When the recording paper reaches a predetermined position 33 (corresponding to the start position of the present invention) below the recording head 38, the carriage 40 starts to reciprocate in the left-right direction 9. As a result, the recording head 38 is scanned in the left-right direction 9 with respect to the recording paper conveyed on the platen 42 provided below the recording unit 24. The recording head 38 ejects ink droplets onto the recording paper. Thereby, an image is recorded on the upper surface (image recording surface) of the recording paper. That is, the predetermined position 33 is the position of the leading edge of the recording paper at the start of image recording. The predetermined position 33 is, for example, the position of the upstream end in the first transport direction in the region on the paper discharge path 65B facing the region where the nozzles are arranged in the recording unit 24.

[Conveying rollers 45, 60, 62]
As shown in FIG. 2, the conveyance unit 59 (an example of the conveyance unit of the present invention) composed of the first conveyance roller 60 and the pinch roller 61 includes an outer guide member 18 and an inner guide member in the first conveyance path 65. 19 and the recording unit 24. The pinch roller 61 is disposed below the first transport roller 60 and is pressed against the roller surface of the first transport roller 60 by an elastic member such as a spring (not shown). The first conveying roller 60 and the pinch roller 61 pinch the recording paper that has been conveyed along the curved path 65A by the feeding roller 25 and convey it in the first conveying direction along the paper discharge path 65B. As a result, the recording sheet is sent onto the platen 42.

  The second conveyance roller 62 and the spur 63 are provided between the recording unit 24 and the upper guide member 82 and the lower guide member 83 in the paper discharge path 65B. The spur 63 is disposed above the second conveyance roller 62 and is pressed against the roller surface of the second conveyance roller 62 by an elastic member such as a spring (not shown). The second conveying roller 62 and the spur 63 pinch the recording sheet on which the image is recorded by the recording unit 24 and convey it to the downstream side in the first conveying direction.

  Each of the transport rollers 60 and 62 is rotated by a rotational driving force transmitted from a transport motor 71 (an example of a second motor of the present invention, see FIG. 6) via a drive transmission mechanism (not shown). That is, the transport motor 71 applies a driving force to the transport rollers 60 and 62. The drive transmission mechanism is composed of a planetary gear or the like. Accordingly, the drive transmission mechanism rotates the transport rollers 60 and 62 in one rotation direction regardless of whether the transport motor 71 is rotated in the normal rotation direction or the reverse rotation direction. Thereby, the recording sheet is conveyed in the first conveying direction.

  The third transport roller 45 and the spur 46 are provided downstream of the branch position 36 in the first transport direction in the paper discharge path 65B. The spur 46 is disposed above the third transport roller 45 and is pressed against the roller surface of the third transport roller 45 by an elastic member such as a spring (not shown).

  The third transport roller 45 is forwardly or reversely rotated by transmitting a driving force in the forward / reverse direction from the transport motor 71 via a drive transmission mechanism (not shown). For example, when single-sided recording is performed, the third transport roller 45 is rotated forward. As a result, the recording sheet is sandwiched between the third conveyance roller 45 and the spur 46 and conveyed downstream, and is discharged to the discharge tray 21. On the other hand, when double-sided recording is performed, the rotation direction of the third conveyance roller 45 is switched from normal rotation to reverse rotation with the third conveyance roller 45 and the spur 46 sandwiching the trailing edge of the recording paper. Thereby, the recording sheet is conveyed in the direction opposite to the first conveyance direction, and is conveyed toward the second conveyance path 67 described later by the path switching unit 41 described below.

[Route switching unit 41]
As shown in FIG. 2, the path switching unit 41 is disposed on the downstream side in the first transport direction with respect to the second transport roller 62 and on the upstream side in the first transport direction with respect to the branch position 36 in the paper discharge path 65B. Has been. The path switching unit 41 includes auxiliary rollers 47 and 48, a flap 49, and a shaft 87.

  A shaft 87 extending in the direction perpendicular to the plane of FIG. 2 (left and right direction 9 in FIG. 1) is provided on the frame of the printer unit 11 and the like. The flap 49 extends from the shaft 87 to the downstream side in the first conveying direction and is pivotally supported by the shaft 87 so as to be rotatable. An auxiliary roller 47 and an auxiliary roller 48 are pivotally supported by the flap 49. The roller surfaces of the auxiliary rollers 47 and 48 are formed in a spur shape in the same manner as the spur 63 and the spur 46.

  The flap 49 is configured such that its posture can be changed, and a discharge posture (posture indicated by a broken line in FIG. 2) positioned above the lower guide member 83 and an extended end portion 49 </ b> A below the branch position 36. It rotates between a reverse posture (posture indicated by a solid line in FIG. 2) entering the position. The flap 49 is in a reverse posture due to its own weight in a normal state, but is rotated to change its posture to the discharge posture by being lifted by the recording paper conveyed through the paper discharge path 65B. Further, when the trailing edge of the recording paper passes through the auxiliary roller 47, the flap 49 rotates by its own weight and changes its posture from the discharge posture to the reverse posture. In this state, when the third conveyance roller 45 continues to rotate normally, the recording sheet is discharged to the sheet discharge tray 21. When the rotation direction of the third conveyance roller 45 is switched from normal rotation to reverse rotation, the recording sheet is It is conveyed toward the second conveyance path 67. The flap 49 may be configured to be rotated by a motor or the like.

[Second transport path 67]
As shown in FIG. 2, the second transport path 67 is branched from the paper discharge path 65 </ b> B at the branch position 36, passes through the lower side of the recording unit 24 and the upper side of the paper feed unit 15, and passes through the first transport path 65. This is a path extending so as to merge with the curved path 65A at the merge position 37 (an example of the merge position of the present invention) on the upstream side of the recording unit 24 in the first conveyance direction. The recording sheet is guided along the second conveyance path 67 in the second conveyance direction (corresponding to the third direction of the present invention). Here, the second transport direction is a direction from the branch position 36 toward the merging direction 37 in the second transport path 67, and indicates a direction indicated by a two-dot chain line with an arrow in FIG. The second transport path 67 is partitioned by the second guide member 32 on the upper side and partitioned by the first guide member 31 on the lower side.

[Fourth transport roller 68]
As shown in FIG. 2, a fourth transport roller 68 (an example of the transport roller of the present invention) and a driven roller 69 are provided in the second transport path 67. The fourth conveyance roller 68 is disposed in the second conveyance path 67 at a position below and opposite to the driven roller 69. The fourth transport roller 68 is rotated by the driving force of the paper feeding motor 70 (see FIG. 6) transmitted by a third transmission unit 74 (an example of the third transmission unit of the present invention) described later. Thus, when the recording sheet conveyed to the second conveying path 67 by the third conveying roller 45 is sandwiched between the fourth conveying roller 68 and the driven roller 69, the fourth conveying roller 68 holds the recording sheet. It is conveyed along the second conveyance path 67 in the second conveyance direction. As a result, the recording sheet is sent to the curved path 65 </ b> A via the merge position 37.

[Drive transmission switching mechanism 50]
As shown in FIG. 3, the printer unit 11 is provided with a drive transmission switching mechanism 50 (an example of the drive transmission switching mechanism of the present invention). The drive transmission switching mechanism 50 transmits the driving force of the paper feeding motor 70 based on the movement of the carriage 40, as will be described in detail below. Selective switching to an example of a separation mechanism.

  The drive transmission switching mechanism 50 includes a first gear 51 (an example of the first gear of the present invention), a second gear 52 (an example of the second gear of the present invention), and a third gear 53 (an example of the third gear of the present invention). ), A fourth gear 54 (an example of the fourth gear of the present invention), a switching lever 55 (an example of the switching lever of the present invention), a coil spring 56 (an example of the urging member of the present invention), the first transmission portion 27, The second transmission unit 57 (an example of the second transmission unit of the present invention) and the third transmission unit 74 (see FIG. 5) are provided.

  The first gear 51 is pivotally supported on the shaft 104 of the paper feed motor 70 protruding in the left-right direction 9 from the paper feed motor 70. As a result, the first gear 51 is driven and transmitted from the paper feed motor 70 and rotated about the left-right direction 9 as an axial direction.

  The second gear 52 is meshed with the first gear 51 with the left-right direction 9 as the axial direction. The second gear 52 is at least a first position (the position of the second gear 52 shown in FIG. 3A, the first position of the present invention) along the left-right direction 9 in a state in which the engagement with the first gear 51 is maintained. And the second position (the position of the second gear 52 shown in FIGS. 3B and 3C, which corresponds to the second position of the present invention). A coil spring 56 is attached to one surface of the second gear 52 in the thrust direction (the right surface in the present embodiment). The coil spring 56 is disposed along the axial direction of the second gear 52, one end is attached to the right side surface of the second gear 52, and the other end is fixed to a fixed surface such as the frame 105 of the printer unit 11. It is attached. Thus, the second gear 52 is urged to the left side by the coil spring 56, that is, from the second position toward the first position. A switching lever 55 described later is in contact with the other surface (the left surface in the present embodiment) of the second gear 52 in the thrust direction. The second gear 52 is movable to the right against the urging force of the coil spring 56 by being pushed by the contact portion 108 of the switching lever 55.

  The third gear 53 is a gear that is rotated about the left-right direction 9 as an axial direction, and meshes with the second gear 52 in the first position. The fourth gear 54 is a gear that is rotated about the left-right direction 9 as an axial direction, and meshes with the second gear 52 in the second position. In other words, the second gear 52 is configured to be able to switch the meshed gear to either the third gear 53 or the fourth gear 54 by moving between the first position and the second position.

  In the drive transmission switching mechanism 50 configured as described above, when the second gear 52 is separated from the third gear 53 and meshed with the fourth gear 54, or away from the fourth gear 54, the third gear 53. Since the positions of the teeth of the gears do not coincide with each other, the second gear 52, the third gear 53, and the fourth gear 54 may not mesh well. That is, there is a possibility that the gear of the second gear 52 is not properly switched.

  Therefore, in the present embodiment, when the gear of the second gear 52 is switched (specifically, immediately after the second gear 52 has moved between the first position and the second position), the control unit 130 (the book 130 described later) According to an example of the control unit of the invention, the forward drive and the reverse drive of the paper feeding motor 70 are alternately executed at least once. In other words, the sheet feeding motor 70 performs at least one operation of being driven to rotate in the reverse direction after being driven in the normal direction or being driven to be rotated in the normal direction after being driven in the reverse direction. For example, the paper feeding motor 70 is executed five times by repeating the forward rotation driving operation after the normal rotation driving operation. Further, the respective drive amounts of the forward rotation drive and the reverse rotation drive of the paper feeding motor 70 are at least a rotation amount equal to or greater than the gap between the teeth of each gear.

  As described above, the forward rotation driving and the reverse rotation driving of the paper feeding motor 70 are alternately performed at least once, whereby the second gear 52 is alternately rotated in the normal rotation and reverse rotation directions. As a result, the teeth of each gear are matched so that they can mesh with each other, and the switching of each gear is performed smoothly and reliably. In the description of “control by the control unit 130”, which will be described later, the above driving of the paper feed motor 70 is described as “forward / reverse rotation of the paper feed motor 70”.

[Switching lever 55]
As shown in FIGS. 3 and 4A, the switching lever 55 includes a protrusion 106, a holding portion 107, and a contact portion 108. The abutting portion 108 is a member that can move along the left-right direction 9 and can rotate about the left-right direction 9 as an axial direction. The right surface in the thrust direction of the contact portion 108 is formed in a spiral shape. When the right surface pushes the contact portion 108, the contact portion 108 rotates. The protrusion 106 protrudes generally upward from the left end portion of the contact portion 108. The holding portion 107 is a plate-like member that is disposed on the upper side of the contact portion 108 and has an opening 110 having an inclined surface 109 and a concave portion 114 as shown in FIG. A protrusion 106 is inserted into the opening 110.

  A portion above the opening 110 of the protrusion 106 is located on the movement path of the carriage 40. The carriage 40 moves in the left-right direction 9 above the paper discharge path 65B when recording an image on recording paper. On the other hand, the carriage 40 is configured to be movable to the upper side outside the paper discharge path 65B in the left-right direction 9. The protrusion 106 can move rightward by being pushed by the carriage 40 that has been moved to the upper outside of the paper discharge path 65B in the left-right direction 9. That is, the protrusion 106 and the contact portion 108 of the switching lever 55 can be moved rightward by being pushed by the carriage 40.

  As shown in FIG. 3A, when the carriage 40 is separated from the protrusion 106, the second gear 52 moves to the left by being urged by the coil spring 56. As a result, as shown in FIG. 4A, the contact portion 108 moves to the left until the protrusion 106 contacts the left end 113 of the opening 110. When the protrusion 106 comes into contact with the left end 113 of the opening 110, the contact portion 108 and the protrusion 106 are positioned as shown in FIG. Hereinafter, the positions of the contact portion 108 and the protrusion 106 of the switching lever 55 are referred to as a third position (corresponding to the third position of the present invention). In the state of FIG. 3A, the second gear 52 is meshed with the third gear 53 and is in the first position. That is, the contact portion 108 of the switching lever 55 in the third position can hold the second gear 52 in the first position by contacting the second gear 52.

  As shown in FIG. 3B, when the protrusion 40 is pushed by the carriage 40 by moving the carriage 40 to the right, the second gear 52 is pushed rightward by being pushed by the contact portion 108. Move to. Further, when the spiral right surface of the contact portion 108 contacts the second gear 52, the protrusion 106 rotates. Thereby, the protrusion 106 fits into the concave portion 114 of the opening 110 as shown by a broken line in FIG. At this time, the contact portion 108 and the protrusion 106 are at the positions shown in FIG. Hereinafter, the positions of the contact portion 108 and the protrusion 106 of the switching lever 55 are referred to as a fourth position (corresponding to the fourth position of the present invention). In the state of FIG. 3B, the second gear 52 is engaged with the fourth gear 54 and is in the second position. That is, the contact portion 108 of the switching lever 55 in the fourth position can hold the second gear in the second position by contacting the second gear 52.

  When the carriage 40 is further moved rightward in the state where the contact portion 108 and the protrusion 106 are in the fourth position, the protrusion 106 moves rightward along the inclined surface 109 as shown in FIG. . Accordingly, the protrusion 106 is located at a position indicated by a one-dot chain line in FIG. In this state, when the carriage 40 is moved leftward, the carriage 40 is separated from the protrusion 106. Then, the contact portion 108 is moved leftward by being pushed by the second gear 52 biased by the coil spring 56. As a result, the contact portion 108 is positioned at the third position as shown in FIG. The protrusion 106 is also positioned at the third position as shown by the solid line in FIG.

  As described above, the contact portion 108 and the protrusion 106 of the switching lever 55 are selectively movable to the third position and the fourth position by contacting the second gear 52.

[First transmission unit 27 and third transmission unit 74]
As shown in FIGS. 3 and 5, the feeding roller 25 has a driving force from the paper feeding motor 70 via the first gear 51, the second gear 52, the third gear 53, and the first transmission unit 27. Transmitted and rotated. That is, the first transmission unit 27 transmits the driving force of the paper feeding motor 70 from the third gear 53 to the feeding roller 25. As shown in FIGS. 2 and 5, the first transmission unit 27 includes a plurality of gears 115 that are meshed with each other.

  As shown in FIG. 5, the fourth transport roller 68 starts from the paper feeding motor 70 (see FIG. 3) to the first gear 51 (see FIG. 3), the second gear 52 (see FIG. 3), and the third gear 53. And, the driving force is transmitted through the third transmission unit 74 and rotated. That is, the third transmission unit 74 transmits the driving force of the paper feeding motor 70 from the third gear 53 to the fourth transport roller 68. As shown in FIG. 5, the third transmission unit 74 includes a plurality of gears 116 that are meshed with each other.

  The drive transmission switching mechanism 50 includes a sun gear 153 that meshes with the third gear 53, and a planet gear 154 that rotates while revolving around the sun gear 153. The planet gear 154 revolves around the sun gear 153 when the third gear 53 rotates in the direction of the arrow 117 due to the reverse rotation of the paper feed motor 70, and thereby the gear 116 constituting the third transmission unit 74. (See the dashed line 154). On the other hand, the planet gear 154 constitutes the first transmission unit 27 by revolving around the sun gear 153 when the third gear 53 rotates in the direction of the arrow 118 due to the forward rotation of the paper feeding motor 70. Meshes with one of the gears 115 (see the solid line 154). With the above configuration, the drive transmission switching mechanism 50 transmits the driving force of the paper feeding motor 70 that rotates in the forward direction to the feeding roller 25 and transmits the driving force of the paper feeding motor 70 that rotates in the reverse direction to the fourth transport roller 68. . That is, the drive transmission switching mechanism 50 selectively switches the transmission of the driving force from the paper feeding motor 70 to the feed roller 25 or the fourth transport roller 68.

[Second transmission unit 57]
As shown in FIG. 3C, the contact / separation mechanism 90 to be described later is provided from the paper feeding motor 70 via the first gear 51, the second gear 52, the fourth gear 54, and the second transmission portion 57. The driving force is transmitted and rotated.

  As shown in FIGS. 3 and 4B and 4D, the second transmission portion 57 includes a sun gear 155 that meshes with the fourth gear 54, and a planet gear 156 that rotates while revolving around the sun gear 155. It is equipped with. The shaft 157 of the planet gear 156 is inserted through a long hole 159 formed in a fixed plate 158 disposed on the right side of the sun gear 155. Thereby, the shaft 157 of the planet gear 156 can slide along the long hole 159. The long hole 159 has a shape that allows the planet gear 156 to maintain meshing with the sun gear 153 despite the sliding of the shaft 157.

  The sun gear 155 is rotated by the rotation of the fourth gear 54 due to the rotation of the sheet feeding motor 70. The planet gear 156 rotates as the sun gear 155 rotates. The contact / separation mechanism 90 is driven by the rotation of the planet gear 156. As described above, the second transmission unit 57 transmits the driving force of the paper feeding motor 70 from the fourth gear 54 to the contact / separation mechanism 90.

[Contact / separation mechanism 90]
As shown in FIG. 3, the contact / separation mechanism 90 is configured so that the conveyance unit 59 has a first posture (corresponding to the first posture of the present invention) in which the pinch roller 61 and the first conveyance roller 60 abut, and the pinch roller 61. And the first conveying roller 60 are changed to a second posture (corresponding to the first posture of the present invention). Here, the conveyance unit 59 in the first posture is shown in FIGS. 3A and 3B, and the conveyance unit 59 in the second posture is shown in FIG. 3C. In the following description, a configuration in which the contact / separation mechanism 90 changes its posture by moving the pinch roller 61 is described. However, the contact / separation mechanism 90 changes its posture by moving the first transport roller 60. May be.

  As shown in FIGS. 3, 4 (C), and 4 (E), the contact / separation mechanism 90 is in contact with the eccentric cam 160 provided on the shaft 157 of the planet gear 156 and the eccentric cam 160 on the upper side of the eccentric cam 160. A fixed plate 161 in contact with the pinch roller 61 and a convex portion 162 projecting from the shaft 35 of the pinch roller 61 toward the shaft 157 of the planet gear 156 are provided. As shown in FIGS. 4C and 4E, the eccentric cam 160 is a disk whose diameter changes periodically from the shaft 157. As shown in FIG. 3, a plurality of pinch rollers 61 are provided along the shaft 35 at a predetermined interval. The convex portion 162 is formed at a position where the pinch roller 61 is not provided on the shaft 35. Further, a hole 163 along the left-right direction 9 is formed in the convex portion 162. The shaft 157 of the planet gear 156 is inserted through the hole 163.

  In the state shown in FIG. 3B (the conveyance portion 59 is in the first posture and the eccentric cam 160 is in the state shown in FIG. 4C), the planet is transmitted by drive transmission from the paper feed motor 70. When the gear 156 is rotated, the eccentric cam 160 is rotated. Thereby, the peripheral surface of the eccentric cam 160 is slid with respect to the fixed plate 161. Since the diameter from the shaft 157 periodically changes on the circumferential surface of the eccentric cam 160, the eccentric cam 160 changes from the state shown in FIG. 4C to the state shown in FIG. That is, the shaft 157 moves downward. In the process of rotation of the eccentric cam 160, the shaft 157 moved downward contacts the lower end of the hole 163. When the shaft 157 moves further downward, as shown in FIG. 3C, the convex portion 162 moves downward by being pushed by the shaft 157. That is, the pinch roller 61 moves downward. Thereby, the conveyance unit 59 changes its posture from the first posture to the second posture. The planet gear 156 moves downward along the long hole 159 by the downward movement of the shaft 157. That is, the planet gear 156 changes from the state shown in FIG. 4B to the state shown in FIG.

  When the planet gear 156 is rotated in the state shown in FIG. 3C (the conveyance unit 59 is in the second posture and the eccentric cam 160 is in the state shown in FIG. 4E), the eccentricity occurs. The cam 160 is rotated, and the posture of the transport unit 59 is changed from the second posture to the first posture, contrary to the above.

[Sheet Detection Unit 120]
As shown in FIG. 2, the printer unit 11 includes a sheet detecting unit 120 that detects the leading and trailing ends of a recording sheet that is fed from the sheet feeding tray 20 and conveyed along the curved path 65A in the first conveying direction. An example of the first detection unit). The sheet detecting unit 120 is provided on the downstream side of the joining position 37 and on the upstream side of the conveying unit 59 in the curved path 65A.

  The sheet detection unit 120 includes, for example, a photo interrupter including a rotating body 112 having detectors 112A and 112B, a light emitting element (for example, a light emitting diode), and a light receiving element (for example, a phototransistor) that receives light emitted from the light emitting element. And the like optical sensor 111. The rotating body 112 is provided to be rotatable about a shaft 123. The detector 112A protrudes from the shaft 123 into the curved path 65A. In a state where no external force is applied to the rotator 112, the detector 112B enters the optical path from the light emitting element to the light receiving element of the optical sensor 111 and blocks light passing through the optical path. When the rotator 112 is rotated by being pushed by the leading edge of the recording paper, the detector 112B is removed from the optical path, and light passes through the optical path.

  The optical sensor 111 outputs an analog electric signal (voltage signal or current signal, an example of the detection signal of the present invention) corresponding to the intensity of light received by the light receiving element to the control unit 130 (see FIG. 6) described later.

[Rotary encoder 73]
As shown in FIG. 6, the multifunction machine 10 includes a rotary encoder 73. The rotary encoder 73 is attached to a shaft (not shown) of the conveyance motor 71, and includes an encoder disk (not shown) that rotates integrally with the shaft and an optical sensor (not shown). The encoder disk has a pattern (not shown) in which a plurality of transmitting portions that transmit light at regular intervals and non-transmitting portions that do not transmit light are alternately arranged at equal pitches in a circumferential direction concentric with the rotation center. Is formed. The optical sensor is provided on the encoder disk at a position facing the position where the pattern is formed. When the encoder disk rotates with the shaft of the conveyance motor 71, the pattern arranged on the encoder disk is detected by the optical sensor. Each time the detection is performed, a pulse signal is generated by the optical sensor. The generated pulse signal is output from the optical sensor to the control unit 130 described later.

[Control unit 130]
As shown in FIG. 6, the control unit 130 controls the overall operation of the multifunction machine 10. The present invention is realized by the control unit 130 performing control according to flowcharts (see FIGS. 7 to 10) described later. The control unit 130 is configured as a microcomputer mainly including a CPU 131, a ROM 132, a RAM 133, an EEPROM 134, and an ASIC 135. These are connected by an internal bus 137.

  The ROM 132 stores a program for the CPU 131 to control various operations. The RAM 133 is used as a storage area for temporarily recording data and signals used when the CPU 131 executes the program, or as a work area for data processing. The EEPROM 134 stores settings, flags, and the like that should be retained even after the power is turned off.

  Connected to the ASIC 135 are a paper feed motor 70, a transport motor 71, and a carriage drive motor 103. When a drive signal for rotating each motor is input from the CPU 131 to a drive circuit corresponding to a predetermined motor, a drive current corresponding to the drive signal is output from the drive circuit to the corresponding motor, thereby corresponding The motor rotates forward or reverse at a predetermined rotational speed. That is, the control unit 130 controls driving of the paper feed motor 70, the transport motor 71, and the carriage drive motor 103, respectively.

  The ASIC 135 receives a pulse signal output from the optical sensor of the rotary encoder 73. The control unit 130 calculates the rotation amount of the transport motor 71 based on the pulse signal from the optical sensor.

  Further, the optical sensor 111 of the sheet detection unit 120 is connected to the ASIC 135. The electrical signal output from the optical sensor 111 is input to the control unit 130. The controller 130 determines whether or not the electrical level (voltage value or current value) of the input signal is equal to or greater than a predetermined value. The input signal is determined as a HIGH level signal when it is equal to or greater than a predetermined value, and is determined as a LOW level signal when it is less than the predetermined value. When the input signal is at a HIGH level, that is, when the sheet detection unit 120 is ON, the control unit 130 is after the leading edge of the recording sheet has passed the rotating body 112 and the trailing edge of the recording sheet is the rotating body 112. It is determined that it is before passing. On the other hand, when the input signal is LOW level, that is, when the sheet detecting unit 120 is OFF, the control unit 130 is in a state before the leading edge of the recording paper reaches the rotating body 112 or the trailing edge of the recording paper rotates. It is determined that the state is after passing through the body 112.

[Control by control unit 130]
Thereafter, the movement of the abutting portion 108 of the switching lever 55, the alternate execution of the forward rotation and reverse rotation driving of the paper feed motor 70, and the posture change of the transport portion 59 are executed by the control portion 130 at a predetermined timing. The processing procedure will be described based on the flowcharts of FIGS. In the following description, it is assumed that the initial state of the contact portion 108 of the switching lever 55 is the third position. The initial posture of the contact / separation mechanism 90 is assumed to be the first posture.

  When an instruction to record an image on a recording sheet is input from the operation panel 17 to the multifunction machine 10, a paper feeding operation is started (S10). Specifically, the control unit 130 drives the paper feeding motor 70 and the conveyance motor 71. The feeding roller 25 and the fourth conveying roller 68 are rotated by driving the sheet feeding motor 70. The recording paper is conveyed along the curved path 65 </ b> A by the rotation of the feeding roller 25. The first conveyance roller 60, the second conveyance roller 62, and the third conveyance roller 45 are rotated by driving the conveyance motor 71.

  The paper feed motor 70 stops after rotating a predetermined amount. Here, the predetermined amount is set in advance to an amount sufficient for the recording paper to reach the nipping position between the first conveying roller 60 and the pinch roller 61.

  Based on the pulse signal from the optical sensor of the rotary encoder 73, the controller 130 determines whether or not the recording sheet has been transported a distance corresponding to the section A (see FIG. 2) (S20). Here, the section A is a section from the leading end position of the recording sheet when the recording sheet starts to be conveyed to the sheet detecting unit 120 in the curved path 65A.

  When it is determined that the recording sheet has been transported a distance corresponding to the section A, the control unit 130 determines whether the leading edge of the recording sheet has reached the sheet detection unit 120 based on the input from the optical sensor 111. (S30). If the sheet detection unit 120 is ON (S30: Yes), step S50 is executed. On the other hand, when the sheet detection unit 120 is OFF (S30: No), the control unit 130 determines that the recording paper is jammed in the curved path 65A of the section A, and executes error processing (S40). For example, the control unit 130 displays a message indicating that the recording paper is jammed on the operation panel 17.

  The control unit 130 determines whether or not the recording sheet has been transported a distance corresponding to the section B and the section C since the sheet detection unit 120 has detected the recording sheet (S50). Here, the section B is a section from the sheet detection unit 120 in the curved path 65A to the recording paper clamping position by the conveyance unit 59 in the curved path 65A. The section C is a section from the recording paper clamping position by the conveyance unit 59 to the predetermined position 33 in the curved path 65A. That is, the control unit 130 determines whether or not the recording sheet has reached the predetermined position 33 (S50).

  When it is determined that the recording sheet has reached the predetermined position 33 (S50: Yes), image recording is started. Specifically, the control unit 130 stops the recording sheet by temporarily stopping the conveyance motor 71. Thereafter, the control unit 130 drives the carriage drive motor 103. Accordingly, the carriage 40 (denoted as CR in FIGS. 7 to 10) is reciprocated in the left-right direction 9 (S60). Further, the control unit 130 ejects ink droplets from the recording head 38 onto the recording paper while moving the carriage 40 (S60). Thereafter, the controller 130 drives the transport motor 71 to transport the recording paper in the first transport direction by a predetermined line feed width (S60). The operation described in step S60 is referred to as “image recording with a predetermined line feed width” in the following description.

  The control unit 130 determines whether or not the recording sheet has been conveyed a predetermined distance after the leading edge of the recording sheet has reached the predetermined position 33 (S70). Here, the predetermined distance is a distance that is set as appropriate within a range in which the trailing edge of the recording sheet does not pass the holding position by the conveyance unit 59. In the present embodiment, the predetermined distance is set in a range where the trailing edge of the recording paper does not pass through the sheet detection unit 120. If it is determined that the recording sheet has not been conveyed a predetermined distance (S70: No), image recording with a predetermined line feed width is executed again (S60).

  On the other hand, also when it is determined that the recording sheet is transported a predetermined distance (S70: Yes), image recording with a predetermined line feed width is executed (S80, S85, S90). However, in steps S80, S85, and S90, processing different from step S60 is executed in the following points. That is, in step S80, the control unit 130 moves the carriage 40 to the right more than when recording an image. Thereby, the carriage 40 pushes the protrusion 106 of the switching lever 55 to the right (see FIG. 3). Thereby, the contact part 108 of the switching lever 55 moves from the third position to the fourth position. Thereby, the second gear 52 moves from the first position to the second position. Thereafter, the control unit 130 performs forward / reverse rotation of the paper feeding motor 70 (S85). As a result, the gear switching is reliably completed.

  That is, the control unit 130 drives the paper feeding motor 70 to drive the feeding roller 25 (S10), and then determines the leading edge position and trailing edge position of the recording paper based on the detection signal of the sheet detection unit 120. During the period when the leading edge of the recording paper passes through the transport section 59 (S30) and the trailing edge of the recording paper does not pass through the transport section 59 (S70), the carriage drive motor 103 is driven to switch the switching lever. The contact portion 108 of 55 is moved from the third position to the fourth position (S80), and the forward drive and the reverse drive of the paper feeding motor 70 are alternately executed at least once (S85). Further, the control unit 130 extends the movement of the carriage 40 in the left-right direction 9 for recording an image on a recording sheet by the recording head 38, thereby moving the contact portion 108 of the switching lever 55 from the third position to the fourth position. The sheet is moved to the position (S80), and the forward rotation drive and the reverse rotation drive of the sheet feeding motor 70 are alternately executed at least once (S85).

  Next, the control unit 130 conveys the recording sheet in the first conveyance direction by a predetermined line feed width (S90).

  After the contact portion 108 of the switching lever 55 is moved to the fourth position, until the trailing edge of the recording sheet passes the sheet detection unit 120, that is, until the sheet detection unit 120 changes from ON to OFF (S100: No). Then, image recording with a predetermined line feed width is repeatedly executed by the control unit 130 (S110).

  When the sheet detection unit 120 is switched from ON to OFF (S100: Yes), the control unit 130 drives the paper feeding motor 70 that has been stopped. As a result, the driving force of the paper feeding motor 70 is transmitted to the contact / separation mechanism 90. As a result, the eccentric cam 160 rotates and the pinch roller 61 is separated from the first transport roller 60. In other words, the conveyance unit 59 changes its posture from the first posture to the second posture (S120).

  That is, the control unit 130 drives the paper feed motor 70 on the condition that the trailing edge of the recording sheet has passed the sheet detection unit 120 (S100), and moves the conveyance unit 59 from the first posture to the second posture. The posture is changed (S120).

  Next, the control unit 130 determines whether or not the conveyance distance of the recording paper after the trailing edge of the recording paper passes the sheet detection unit 120 exceeds the distance corresponding to the section B (S130). In other words, the control unit 130 determines whether the trailing edge of the recording paper has passed the recording paper nipping position by the transport unit 59 (S130). Until the trailing edge of the recording sheet passes the recording sheet clamping position by the conveyance unit 59 (S130: No), image recording with a predetermined line feed width is repeatedly executed (S140).

  When it is determined that the trailing edge of the recording sheet has passed the recording sheet holding position by the conveyance unit 59 (S130: Yes), the control unit 130 is instructed to record an image on a plurality of recording sheets on the operation panel 17. And whether or not image recording on both sides of the recording paper is instructed (S150). Furthermore, when image recording on a plurality of recording papers is instructed, the control unit 130 designates whether or not all of the image recording on the designated number of recording papers has been completed and image recording on both sides. In step S150, it is determined whether image recording on the front and back surfaces has been completed.

  When the instruction for image recording on the recording sheet is not for a plurality of recording sheets or for both sides of the recording sheet (S150: No), until the image recording on the recording sheet on which image recording is currently being performed is completed. (S170: No), image recording with a predetermined line feed width is repeatedly executed (S170). When the image recording on the recording sheet on which the image recording is currently being performed is completed (S160: Yes), the series of control ends.

  Alternatively, even when the instruction for image recording on the recording paper is for a plurality of recording papers, when the image recording on the designated number of recording papers is completed, and the instruction for image recording on the recording paper However, even when the image recording is performed on both sides of the recording sheet or when the image recording on both sides of the recording sheet is completed (S150: No), the image recording on the recording sheet on which the image recording is currently performed is completed. Up to (S170: No), image recording with a predetermined line feed width is repeatedly executed (S170). When the image recording on the recording sheet on which the image recording is currently being performed is completed (S160: Yes), the series of control ends.

  On the other hand, when the image recording instruction on the recording sheet is for a plurality of recording sheets and the image recording of the designated number of recording sheets is not completed, or the image recording instruction on the recording sheet is recorded. If it is for both sides of the paper and the image recording on the back side of the recording paper has not been completed (S150: Yes), the controller 130 drives the paper feed motor 70. As a result, the driving force of the paper feeding motor 70 is transmitted to the contact / separation mechanism 90. As a result, the eccentric cam 160 rotates and the pinch roller 61 comes into contact with the first conveying roller 60. In other words, the conveyance unit 59 changes its posture from the second posture to the first posture (S180).

  Thereafter, the control unit 130 moves the carriage 40 to the right more than when recording an image. As a result, the carriage 40 pushes the protrusion 106 of the switching lever 55 to the right. Thereby, the contact part 108 of the switching lever 55 moves from the fourth position to the third position (S190). Thereby, the second gear 52 moves from the second position to the first position. Thereafter, the control unit 130 performs forward / reverse rotation of the paper feeding motor 70 (S195). As a result, the gear switching is reliably completed. Note that the movement of the carriage 40 in step S190 may be performed when image recording is performed, as in step S80. That is, the carriage 40 may move rightward for image recording, and then push the protrusion 106 of the switching lever 55 to the right by extending the distance of the movement.

  As described above, the control unit 130 has moved the contact portion 108 of the switching lever 55 to the fourth position (S80), and after the trailing edge of the recording paper has passed the transport unit 59 (S130). In addition, in a period before the end of image recording on the recording paper by the recording head 38 (S160), the feeding unit 59 is driven from the second posture to the first position by driving the feeding motor 70 for a predetermined period and then stopping. After the posture is changed (S180), the carriage drive motor 103 is driven to move the contact portion 108 of the switching lever 55 from the fourth position to the third position (S190). Driving and reverse driving are alternately executed at least once (S195).

  Thereafter, the control unit 130 repeatedly executes image recording with a predetermined line feed width (S210) until image recording on the recording sheet on which image recording is currently being performed is completed (S200: No). When the image recording on the recording sheet on which image recording is currently being performed is completed (S200: Yes), the processing from step S10 is executed again. That is, a series of processes (S10 to S150, S180 to S210) for executing image recording on the next recording sheet or image recording on the back side of the recording sheet is executed.

  When a series of processes for executing image recording on the back side of the recording sheet is executed, the following points are different from the above description. That is, section D is used instead of section A. Here, the section D is a section from the fourth conveying roller 68 and the driven roller 69 to the position where the recording paper is held and the sheet detecting unit 120 in the curved path 65A.

  In the above-described series of processing, in step S150, the control unit 130 completes image recording on the designated number of recording sheets, and image recording on the front and back surfaces when image recording on both sides is designated. Is repeatedly executed until it is determined that the process has been completed (S150: No).

[Effect of the embodiment]
When the contact portion 108 of the switching lever 55 is moved from the third position to the fourth position, the second gear 52 is moved from the first position to the second position. Thereafter, the feed motor 70 alternately performs forward rotation and reverse rotation at least once so that the second gear 52 is disconnected from the third gear 53 and the second gear 52 is separated from the fourth gear 54. The meshing is complete. As described above, the contact portion 108 of the switching lever 55 is moved from the third position to the fourth position, and the paper feed motor 70 is driven forward / reversely, whereby the drive from the paper feed motor 70 to the contact / separation mechanism 90 is performed. Transmission is possible.

  According to this embodiment, the movement of the contact portion 108 of the switching lever 55 and the forward / reverse driving of the paper feeding motor 70 are such that the leading edge of the recording paper passes through the conveying portion 59 and the recording paper It is executed during a period when the end does not pass through the transport unit 59. During the period, the recording paper is conveyed by the conveyance unit 59. That is, even when the movement of the contact portion 108 of the switching lever 55 and the forward / reverse driving of the paper feeding motor 70 are executed during the period, image recording is started from the start of feeding of the recording paper from the paper feeding tray 20. The time until the sheet is discharged through the recording medium, that is, the time for a series of processes for image recording does not increase significantly. In other words, according to the present embodiment, before the trailing edge of the recording sheet sandwiched by the conveyance unit 59 comes out of the conveyance unit 59 without significantly increasing the time for a series of processes for image recording. In addition, it is possible to prepare a posture for separating the first conveyance roller 60 and the pinch roller 61 constituting the conveyance unit 59.

  Further, according to the present embodiment, the movement of the carriage 40 for moving the second gear 52 to the second position can be executed only by extending the movement distance of the carriage 40 for recording an image on a recording sheet.

  Further, according to the present embodiment, the paper feed motor 70 is provided on the condition that the trailing edge of the recording sheet has passed through the sheet detection unit 120 provided on the upstream side in the first conveyance direction from the conveyance unit 59. Driven, the conveyance unit 59 changes its posture from the first posture to the second posture. Therefore, the pinch roller 61 and the first conveyance roller 60 can be separated before the trailing edge of the recording sheet passes through the conveyance unit 59.

  Further, according to the present embodiment, the contact portion 108 of the switching lever 55 is moved from the fourth position to the third position before the image recording on the recording paper is completed. As a result, the drive transmission from the sheet feeding motor 70 to the feeding roller 25 is enabled. As a result, it is possible to quickly perform the operation of feeding the recording sheet from which the image is recorded next, or the recording sheet on which only the front side is image-recorded and the back side is not recorded from the paper feed tray 20.

[Modification 1 of Embodiment]
In the above-described embodiment, the control unit 130 contacts the switching lever 55 during a period in which the leading edge of the recording paper passes through the conveyance unit 59 and the trailing edge of the recording paper does not pass through the conveyance unit 59. The part 108 was moved from the third position to the fourth position. Therefore, the control unit 130 drives the carriage drive motor 103 to move the switching lever 55 from the third position to the third position during a period in which the leading edge of the recording paper passes through the conveyance unit 59 and does not reach the predetermined position 33. It is also possible to move to the four positions and alternately perform forward rotation driving and reverse rotation driving of the paper feeding motor 70 at least once.

  Hereinafter, the procedure of the process by the control unit 130 in Modification 1 will be described based on the flowchart of FIG. 9. In the following description, the initial state of the contact portion 108 of the switching lever 55 and the contact / separation mechanism 90 is assumed to be the same as in the above-described embodiment. Detailed description of the same processing as that of the above-described embodiment is omitted.

  The processes of steps S310 to S340 are the same as steps S10 to S40 in the above-described embodiment.

  When the sheet detection unit 120 is ON (S330: Yes), the control unit 130 determines whether the recording sheet has been conveyed a predetermined distance after being detected by the sheet detection unit 120 (S350). Here, the predetermined distance is a distance that is appropriately set within a range in which the leading edge of the recording paper does not reach the predetermined position 33. In other words, the predetermined distance is a distance that is appropriately set in a range smaller than the sum of the sections B and C.

  If it is determined that the recording sheet has been conveyed a predetermined distance (S350: Yes), the control unit 130 executes the process of step S360. In other words, the control unit 130 drives the carriage drive motor 103 to move the carriage 40 to the right more than when recording an image. As a result, the carriage 40 pushes the protrusion 106 of the switching lever 55 to the right. Thereby, the contact part 108 of the switching lever 55 moves from the third position to the fourth position. Thereby, the second gear 52 moves from the first position to the second position. Thereafter, the control unit 130 executes forward / reverse rotation of the paper feeding motor 70 (S365). As a result, the gear switching is reliably completed.

  Next, the control unit 130 determines whether or not the recording sheet has reached the predetermined position 33 in the same manner as in step S50 in the above-described embodiment (S370). When it is determined that the recording sheet has reached the predetermined position 33 (S370: Yes), image recording is started (S380). That is, until the image recording is completed for the entire image recording area of the recording paper (S390), the “image recording with a predetermined line feed width” described in the above embodiment is repeated.

  The controller 130 determines whether or not the recording paper is jammed in the first conveyance path 65 during image recording on the recording paper (S400).

  The determination is performed by the control unit 130 based on a detection signal from a linear encoder (not shown) for calculating the rotation amount of the carriage drive motor 103, for example. This will be described in detail below. The linear encoder includes an encoder strip (not shown) disposed on the belt constituting the belt driving mechanism described above and a photo interrupter (not shown) that detects the encoder strip. The photo interrupter detects the encoder strip. The control unit 130 controls the movement of the carriage 40 based on the detection signal of the linear encoder. Then, when the control unit 130 finds an abnormality in the input detection signal (for example, when the detection signal determines that the carriage 40 that should have moved is stopped), the recording sheet and the carriage It is determined that the carriage 40 is stopped due to the collision of the 40 or the like. That is, the control unit 130 determines that the recording paper is jammed in the first conveyance path 65.

  Further, the determination may be performed in the same manner as Steps S30 and S40 in the above-described embodiment based on the electrical signal from the sheet detection unit 120.

  When it is determined that the recording paper is jammed in the first conveyance path 65 (S400: Yes), the control unit 130 moves the conveyance unit 59 from the first posture to the second posture in the same manner as in step S120 in the above-described embodiment. The posture is changed (S410).

  As described above, in the first modification, the control unit 130 moves the switching lever 55 to the fourth position (S360), and then the recording paper is jammed in the first conveyance path 65 based on the electrical signal from the sheet detection unit 120. On condition that it is determined that it has been (S400), the paper feed motor 70 is driven to change the posture of the transport unit 59 from the first posture to the second posture (S410).

  Normally, when the recording paper is jammed inside the multi function device 10 during image recording on the recording paper, the carriage 40 is stopped. As a result, the carriage 40 cannot move the switching lever 55. However, according to the first modification, the switching lever 55 is moved to the fourth position by the carriage 40 before the image recording on the recording paper is started. As a result, the second gear 52 is moved to the second position. Thus, when the recording paper is jammed inside the multifunction machine 10 during image recording on the recording paper, the pinch roller 61 and the first conveying roller 60 are separated by driving the paper feeding motor 70. Can do. As a result, even when the recording paper is jammed while being sandwiched between the first conveying roller 60 and the pinch roller 61, the recording paper can be easily taken out from the multifunction machine 10.

  In this embodiment, when the control unit 130 determines that the recording paper is jammed, the control unit 130 drives the paper feeding motor 70 to separate the pinch roller 61 and the first transport roller 60 from each other. That is, according to the present embodiment, the separation between the pinch roller 61 and the first transport roller 60 can be automatically executed by the control unit 130 in a necessary situation.

[Modification 2 of the embodiment]
In the first modification, the control unit 130 determines whether the recording paper is jammed in the first conveyance path 65 based on the electrical signal from the sheet detection unit 120. However, as will be described later, the outer guide member 18 is configured to be capable of changing the posture, and the guide member detection unit 121 (an example of the second detection unit of the present invention) that detects the posture of the outer guide member 18 is the multifunction device 10. When the guide member detection unit 121 detects that the outer guide member 18 is in a posture to expose the first transport path 65 after the switching lever 55 is moved to the fourth position. On the condition that it is detected, the feeding motor 70 may be driven to change the posture of the transport unit 59 from the first posture to the second posture.

  As shown in FIG. 2, the outer guide member 18 in Modification 2 is a shaft 86 (see FIG. 2) that extends in the left-right direction 9 (perpendicular to the plane of FIG. 2) near the lower end in the up-down direction 7. Is configured to be rotatable in the direction of an arrow 79. The outer guide member 18 is closed so that at least a part of the first conveyance path 65, that is, the curved path 65A is shielded from the outside of the multifunction machine 10 by the rotation (the state shown by the solid line in FIG. 4), and an exposed posture (indicated by a broken line in FIG. 2) that exposes the curved path 65A (specifically, the inner guide member 19 that defines the inner side of the curved path 65A), the present invention. To the third posture).

  The outer guide surface 18A (corresponding to the guide surface of the present invention) constituting the front surface of the outer guide member 18 divides the outer side of the curved path 65A when the outer guide member 18 is in the closed posture, and records the recording paper. To guide. On the other hand, the outer guide surface 18A tilts rearward when the outer guide member 18 is in the exposed posture, and therefore does not partition the curved path 65A and does not guide the recording paper.

  In the second modification, the configuration in which the posture is changed by the rotation of the outer guide member 18 has been described. However, the method of changing the posture of the outer guide member 18 is not limited to the rotation. For example, the outer guide member 18 may change its posture between an exposed posture and a closed posture by being attached to and detached from the multifunction device 10.

  The guide member detection unit 121 includes, for example, a light emitting unit and a light emitting unit provided so as to sandwich the protrusion 16 provided in the vicinity of the rotation tip of the outer guide member 18 in the closed posture, as indicated by a broken line in FIG. It consists of a light receiving part. When the outer guide member 18 is in the closed posture, the light emitted from the light emitting unit is not received by the light receiving unit. On the other hand, when the outer guide member 18 is in the exposed posture, the projection 16 does not exist between the light emitting unit and the light receiving unit, and thus the light emitted from the light emitting unit is received by the light receiving unit. Thereby, the posture of the outer guide member 18 is detected by the guide member detection unit 121.

  Hereinafter, the procedure of the process by the control unit 130 in Modification 2 will be described based on the flowchart of FIG. In the following description, the initial state of the contact portion 108 of the switching lever 55 and the contact / separation mechanism 90 is assumed to be the same as in the above-described embodiment. In the following, only step 500, which is a process different from that of the first modification, will be described in detail.

  In the second modification, when it is determined that the recording paper is jammed in the conveyance paths 65 and 67 (S400: Yes), the control unit 130 determines the outer guide member based on the signal from the light receiving unit of the guide member detection unit 121. 18 postures are detected (S500). When the outer guide member 18 is in the exposed posture (S500: Yes), the posture of the transport unit 59 is changed from the first posture to the second posture in the same manner as in Step S410 in the first modification.

  That is, in the second modification, after the control unit 130 moves the switching lever 55 to the fourth position (S360), the guide member detection unit 121 detects that the outer guide member 18 is in the exposed posture. As a condition (S500), the paper feed motor 70 is driven to change the posture of the transport unit 59 from the first posture to the second posture (S410).

  According to the present embodiment, when the recording paper is jammed inside the multifunction device 10, the user can change the posture of the outer guide member 18 to the exposed posture and take out the recording paper from the multifunction device 10. According to the present embodiment, the control unit 130 drives the paper feeding motor 70 on the condition that the outer guide member 18 is in the exposed posture. As a result, the pinch roller 61 and the first transport roller 60 are separated from each other. That is, according to the present embodiment, the separation between the pinch roller 61 and the first transport roller 60 can be automatically executed by the control unit 130 in a necessary situation.

DESCRIPTION OF SYMBOLS 10 ... Multifunction machine 18 ... Outer guide member 20 ... Paper feed tray 25 ... Feed roller 27 ... First transmission part 38 ... Recording head 40 ... Carriage 50 ... Drive transmission switching mechanism 51 ... first gear 52 ... second gear 53 ... third gear 54 ... fourth gear 55 ... switching lever 56 ... coil spring 57 ... second Transmission unit 59 ... transport unit 65 ... first transport path 67 ... second transport path 68 ... fourth transport roller 70 ... paper feed motor 71 ... transport motor 74 ... Third transmission unit 90 ... contact / separation mechanism 103 ... carriage drive motor 120 ... sheet detection unit 121 ... guide member detection unit 130 ... control unit

Claims (8)

A placement section on which a sheet can be placed;
A first conveyance path through which a sheet is guided;
A feeding roller that feeds the sheet placed on the placement unit to the first conveyance path;
A conveying unit that includes a driving roller and a driven roller, and conveys the sheet sent to the first conveying path by the feeding roller in a first direction;
A contact / separation mechanism that changes the posture of the transport unit to a first posture in which the driven roller and the driving roller are in contact with each other and a second posture in which the driven roller and the driving roller are separated from each other;
A first detection unit that is provided upstream of the conveyance unit in the first direction, detects a front end and a rear end of the sheet conveyed in the first direction, and outputs a detection signal;
A carriage that is reciprocally movable in a second direction perpendicular to the first direction and along the image recording surface of the sheet on the downstream side in the first direction from the conveying unit;
A recording head that is mounted on the carriage and that records an image on an image recording surface by discharging ink droplets toward a sheet conveyed through the first conveyance path;
A first motor for applying a driving force to the carriage;
A second motor for applying a driving force to the driving roller;
A third motor for applying a driving force to the feeding roller and the contact / separation mechanism;
A drive transmission switching mechanism for selectively switching transmission of the driving force of the third motor to the feeding roller or the contact / separation mechanism based on the movement of the carriage;
A control unit for controlling the driving of the first motor, the second motor, and the third motor, respectively,
The drive transmission switching mechanism is
A first gear that is driven and transmitted from the third motor and rotated about the second direction as an axial direction;
The second direction is engaged with the first gear with the second direction as an axial direction, and is movable to at least a first position and a second position along the second direction while maintaining the engagement with the first gear. Two gears,
A third position that can move in the second direction when the carriage abuts, and that can hold at least the second gear at the first position by abutting the second gear, and the second gear. A switching lever that can be selectively moved to a fourth position that can be held in the second position;
A biasing member that biases the second gear from the second position toward the first position;
A third gear meshing with the second gear in the first position;
A fourth gear meshing with the second gear in the second position;
A first transmission portion for transmitting the driving force of the third motor from the third gear to the feeding roller;
A second transmission portion for transmitting the driving force of the third motor from the fourth gear to the contact / separation mechanism,
The control unit
After driving the third motor to drive the feeding roller, the front end position and the rear end position of the sheet are determined based on the detection signal of the first detection unit, and the front end of the sheet passes through the conveyance unit. And the first motor is driven to move the switching lever from the third position to the fourth position during a period when the trailing edge of the sheet does not pass through the conveyance unit, and the third motor An image recording apparatus that executes forward rotation and reverse rotation alternately at least once. The control unit
By extending the movement of the carriage for recording an image on the sheet by the recording head in the second direction, the switching lever is moved from the third position to the fourth position, and the third motor The image recording apparatus according to claim 1, wherein the forward drive and the reverse drive are alternately executed at least once. The control unit
The condition according to claim 1 or 2, wherein the third motor is driven to change the posture of the conveying unit from the first posture to the second posture on the condition that the rear end of the sheet has passed the first detection unit. The image recording apparatus described. The control unit
After moving the switching lever to the fourth position, after the trailing edge of the sheet has passed through the conveying section, and before the end of image recording on the sheet by the recording head The third motor is driven for a predetermined period and then stopped to change the conveying section from the second posture to the first posture, and then the first motor is driven to move the switching lever to the first posture. The image recording apparatus according to claim 3, wherein the image recording apparatus is moved from four positions to the third position, and the forward rotation drive and the reverse rotation drive of the third motor are alternately executed at least once. Branched from the first transport path at a downstream branch position in the first direction with respect to the recording head, and joined with the first transport path at a merge position in the upstream in the first direction with respect to the first detection unit. A second conveyance path that is guided in a third direction from the branching position to the merging position;
A conveyance roller that is provided in the second conveyance path and conveys the sheet in the third direction along the second conveyance path;
The image recording apparatus according to claim 4, further comprising: a third transmission unit configured to transmit a driving force of the third motor from the third gear to the transport roller. The control unit
The first motor is driven to move the switching lever from the third position to the first position during a period in which the leading edge of the sheet has passed through the conveyance unit and has not reached the image recording start position by the recording head. 2. The image recording apparatus according to claim 1, wherein the image recording apparatus is moved to four positions to alternately perform forward rotation and reverse rotation of the third motor at least once. The control unit
After moving the switching lever to the fourth position, the third motor is driven on the condition that it is determined that the sheet is jammed in the first conveyance path, and the conveyance unit is moved from the first posture to the first position. The image recording apparatus according to claim 6, wherein the posture is changed to the second posture. A guide surface that divides the outside of the first transport path is provided, a third posture that exposes at least a part of the first transport path to the outside of the apparatus, and at least a part of the first transport path A guide member that is shielded from the outside of the apparatus and capable of changing its posture to a fourth posture capable of guiding the sheet by the guide surface;
A second detection unit that detects the posture of the guide member;
The control unit
After moving the switching lever to the fourth position, the third motor is driven on the condition that the second detection unit detects that the guide member is in the third posture, and The image recording apparatus according to claim 6, wherein the posture of the transport unit is changed from the first posture to the second posture.

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