Patent Publication Number: US-2016236489-A1

Title: Recording apparatus

Description:
BACKGROUND 
     1. Technical Field 
     The present invention relates to a recording apparatus that performs recording on a recording medium. 
     2. Related Art 
     There are cases in which configurations that drive a plurality of paper sheet feeding units with a single driving source (motor) as shown in Japanese Patent No. 4605239, are adopted in a printer. In this case, a driving force transmission switching unit, which is configured by a planetary gear mechanism or the like, is provided between the motor and each paper sheet feeding unit so that a driving force is selectively transmitted to a predetermined paper sheet feeding unit, and the transmission of driving force to the other paper sheet feeding units is interrupted. 
     In addition, in particular, in a case in which the motor drives a transport roller, which is provided on the downstream side of the paper sheet feeding unit, in addition to the paper sheet feeding unit, it is necessary to set the rotation of a feeding roller of the paper sheet feeding unit to be a single rotation in a state in which the transport roller is rotated continuously, and therefore, there are cases in which a clutch, referred to as a so-called one-time clutch (a single rotation clutch) or the like, is provided (JP-A-2004-231326). Furthermore, even if the rotational direction of the motor switches between regular and counter rotation, for example, there are cases in which a clutch, referred to as a so-called one-way clutch (a single direction clutch) or the like, which transmits a driving force in a regular rotation direction and does not transmit a driving force in a counter rotation direction, is provided (JP-A-2009-250385). 
     In this instance, the following problems arise in a configuration that selects a paper sheet feeding unit to be driven with switching of the rotational direction of the motor, or more specifically, with the switching of a state of the planetary gear following the switching of the rotational direction of the motor. That is, in a case of performing a skew elimination action, which corrects oblique motion (skew) of a sheet of paper using a transport roller that is provided on the downstream side of the paper sheet feeding unit, it is necessary to switch the transport roller from regular rotation driving to counter rotation driving. At this time, in a case in which, for example, the sheet of paper is fed using a first paper sheet feeding unit (operated by regular rotation of the motor), a driving force is transmitted to a second paper sheet feeding unit (operated by counter rotation of the motor) due to switching of the transport roller (the motor) from regular rotation driving to counter rotation driving, and therefore, there is a concern that a sheet of paper will be unintentionally fed from the second paper sheet feeding unit. 
     SUMMARY 
     An advantage of some aspects of the invention is to prevent driving of a paper sheet feeding unit, the driving of which is not intended, in a configuration that drives a plurality of paper sheet feeding units and a transport roller using a single driving source. 
     According to a first aspect of the invention, there is provided a recording apparatus including a recording unit that performs recording on a medium, a transport roller that transports the medium, and that rotates in a direction for transporting the medium to a downstream side when a motor is regularly rotated, and rotates in a direction for transporting the medium to an upstream side when the motor is counter rotated, a first feeding unit that is capable of accommodating the medium, and that delivers the medium toward the transport roller when the motor is regularly rotated by obtaining a driving force from the motor, a second feeding unit that is capable of accommodating the medium, and that delivers the medium toward the transport roller when the motor is counter rotated by obtaining a driving force from the motor, a planetary gear mechanism that is configured to include a sun gear which rotates as a result of receiving the driving force of the motor, and a planetary gear which performs planetary motion around the sun gear, and that is configured such that the planetary gear is positioned in a separation position, in which the planetary gear is separated from a transmission gear that transmits a driving force to the second feeding unit, when the motor is regularly rotated, and such that planetary gear is positioned in a mesh position, in which the planetary gear meshes together with the transmission gear, when the motor is counter rotated, and a control unit that controls the rotation time of the motor, in which the control unit is capable of executing a skew correction mode, which causes a leading end of the medium to follow the transport roller by switching from regular rotation of the motor to counter rotation thereof for a predetermined period of time in a feeding mode, which feeds the medium from the first feeding unit, and a movement amount of the planetary gear when the motor is counter rotated for a predetermined period of time is set to be smaller than a movement amount to reach the mesh position from the separation position. 
     According to the aspect, since the movement amount of the planetary gear when the motor is counter rotated for a predetermined period of time during the execution of the skew correction mode, is set to be smaller than a movement amount to reach the mesh position from the separation position, that is, a movement amount required to switch a driving target from the first feeding unit to the second feeding unit, even if the motor is counter rotated for a predetermined period of time during the skew correction mode, the driving target does not switch from the first feeding unit to the second feeding unit. As a result of this, it is possible to perform suitable feeding control without the medium being unintentionally sent from the second feeding unit during the skew correction mode. 
     In the recording apparatus of a second aspect of the invention, the first feeding unit may have a configuration that delivers the medium from a medium accommodation section, which accommodates the medium in a substantially flat manner, and the second feeding unit may have a configuration that delivers the medium from a medium setting section, in which the medium is set with an inclined posture. 
     According to the aspect, it is possible to obtain the functional effect of the abovementioned first aspect in a configuration in which the first feeding unit has a configuration that delivers the medium from a medium accommodation section, which accommodates the medium in a substantially flat manner, and the second feeding unit delivers the medium from a medium setting section, in which the medium is set with an inclined posture. 
     The recording apparatus of a third aspect of the invention may further include a carriage that is provided with the recording unit, and that is capable of moving in a direction that intersects a transport direction of the medium, and a switching unit that switches between a transmission state in which the rotation of the motor is transmitted to the first feeding unit and the second feeding unit by engaging with the carriage, and an interruption state in which the transmission is interrupted, and the control unit may be provided with a normal feeding mode, which performs state switching of the switching unit each time a sheet of the medium is delivered from the first feeding unit by performing state switching of the switching unit via the carriage, and a continuous feeding mode, which continuously delivers a plurality of sheets of the medium from the first feeding unit while retaining the switching unit in the transmission state. 
     According to the aspect, driving force transmission from the motor to the first feeding unit and the second feeding unit is retained in the continuous feeding mode (however, the driving of the second feeding unit depends on the rotational direction of the motor due to the planetary gear mechanism). Accordingly, the planetary gear moves toward the mesh position from the separation position when the skew correction mode is executed during feeding of the medium from the first feeding unit, but as a result of the abovementioned first aspect, the driving target does not switch from the first feeding unit to the second feeding unit. As a result of this, in the continuous feeding mode, it is possible to perform suitable feeding control without the medium being unintentionally sent from the second feeding unit during the skew correction mode. 
     In the recording apparatus of a fourth aspect of the invention, the second feeding unit may be provided with a feeding roller that delivers the medium, a hopper that supports the medium in an inclined posture, that is capable of switching between a state in which the feeding roller comes into pressure contact with the medium as a result of swinging, and a state in which the medium is separated from the feeding roller, and that configures the medium setting section, a cam that engages with the hopper and rotates by obtaining a driving force from the transmission gear, and that executes state switching of the hopper a single time during a single rotation action, and a gear group that transmits a driving force from the transmission gear to the feeding roller, and that causes the feeding roller to rotate a plurality of times during a single rotation action of the cam. 
     According to the aspect, since the recording apparatus has a configuration that rotates the feeding roller a plurality of times during a single rotation action of the cam, it is possible to reduce the diameter of the feeding roller, and therefore, it is possible to achieve miniaturization of the apparatus. 
     In the recording apparatus of a fifth aspect of the invention, the second feeding unit may be provided with a feeding roller that delivers the medium, a rotational shaft on which the feeding roller is provided, and a clutch that allows idling of the feeding roller with respect to the rotational shaft when the medium that is delivered from the second feeding unit is transported to the downstream side by the transport roller. 
     According to the aspect, since the recording apparatus is provided with the clutch that allows idling of the feeding roller with respect to the rotational shaft when the medium that is delivered from the second feeding unit is transported to the downstream side by the transport roller, it is possible to eliminate or reduce a load that the feeding roller applies to the medium when the medium that is delivered from the second feeding unit is transported to the downstream side by the transport roller, and therefore, it is possible to suitably perform medium transport using the transport roller. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIG. 1  is an external perspective view of a printer according to the invention. 
         FIG. 2  is a lateral cross-sectional view that shows a paper sheet transport pathway of the printer according to the invention. 
         FIG. 3  is a perspective view of a pathway that transmits a driving force from a transport driving roller to a front feeding device and a rear feeding device. 
         FIG. 4  is a perspective view of a pathway that transmits a driving force from the transport driving roller to the front feeding device and the rear feeding device. 
         FIG. 5  is a perspective view of a pathway that transmits a driving force from the transport driving roller to the front feeding device and the rear feeding device. 
         FIG. 6  is a perspective view of a pathway that transmits a driving force from the transport driving roller to the front feeding device and the rear feeding device. 
         FIG. 7  is a perspective view of a switching unit that switches between a state in which the rotation of the transport driving roller is transmitted by engaging with a carriage, and a state in which the transmission is interrupted. 
         FIG. 8  is a perspective view of a switching unit that switches between a state in which the rotation of the transport driving roller is transmitted by engaging with the carriage, and a state in which the transmission is interrupted. 
         FIG. 9  is a front view of a planetary gear mechanism. 
         FIG. 10  is a perspective view of the rear feeding device. 
         FIG. 11  is a perspective view of a driving mechanism section in the rear feeding device. 
         FIG. 12  is a perspective view of a clutch that is provided between a feeding roller and a rotational shaft of the rear feeding device. 
         FIG. 13  is a perspective view of the clutch that is provided between the feeding roller and the rotational shaft of the rear feeding device. 
         FIG. 14  is a lateral cross-sectional view of the rear feeding device. 
         FIG. 15  is a view that shows an embodiment of the clutch. 
         FIG. 16  is a view that shows another embodiment of the clutch. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, an embodiment of the invention will be described on the basis of the drawings, but the invention is not limited to the embodiment described below, various modifications are possible within the range of the invention that is set forth in the claims, and the following embodiment of the invention will be described on the premise that such modifications are also included within the range of the invention. 
       FIG. 1  is an external perspective view of a printer  1  according to the invention,  FIG. 2  is a lateral cross-sectional view that shows a paper sheet transport pathway of the printer  1 , and  FIGS. 3 to 6  are perspective views of a pathway that transmits a driving force from a transport driving roller  21  to a front feeding device  10  and a rear feeding device  7 . 
     In addition,  FIGS. 7 and 8  are perspective views of a switching unit  67  that switches between a state in which the rotation of the transport driving roller  21  is transmitted by engaging with a carriage  24 , and a state in which the transmission is interrupted, and  FIG. 9  is a front view of a planetary gear mechanism. 
     Furthermore,  FIG. 10  is a perspective view of the rear feeding device  7 ,  FIG. 11  is a perspective view of a driving mechanism section in the rear feeding device  7 ,  FIGS. 12 and 13  are perspective views of a clutch that is provided between a feeding roller  29  and a rotational shaft  30  of the rear feeding device  7  (a one-way latch mechanism  28 ). Furthermore,  FIG. 14  is a lateral cross-sectional view of the rear feeding device  7 , and  FIGS. 15 and 16  are views that show an embodiment of a clutch  67 . 
     Additionally, an x-y-z coordinate system in each drawing shows directions, and a z direction shows a vertical direction (an apparatus height direction), a y direction shows a paper sheet transport and ejection direction (an apparatus front-back direction), and an x direction shows a paper sheet width direction (an apparatus left-right direction). 
     1. Overall Configuration of Printer 
     Hereinafter, an overall configuration of the printer  1 , which is an embodiment of a recording apparatus of the invention, will be outlined with reference to  FIGS. 1 and 2 . The printer  1  is provided with a scanner unit  3  above an apparatus main body (a recording section)  2  that performs ink jet recording on recording paper sheets, as an example of a medium, that is, is configured as a multifunction machine that is provided with a scanning function in addition to an ink jet recording function. 
     The scanner unit  3  is provided to be capable of revolving with respect to the apparatus main body  2 , and can have a closed state ( FIG. 1 ) or an open state (not illustrated in the drawings) as a result of being revolved. 
     A cover  4 , which is above the scanner unit  3 , is a cover that is capable of opening and closing, and a manuscript stand (not illustrated in the drawings) of the scanner unit  3  is displayed by opening the cover  4 . 
     The reference numeral  5  on the front surface of the apparatus is an operational panel that is provided with a power button, operation buttons, which perform various printing settings and the execution of recording, a display section, which performs preview display of printing settings content and printing images, and the like. 
     In addition, the reference numeral  44  on the front surface of the apparatus is a cover, in which a lower stage side tray  40  is provided, and which is capable of opening and closing, and, as shown in  FIG. 1 , is configured so that the lower stage side tray  40 , an upper stage side tray  45  and a paper ejection reception tray  8 , as a medium accommodation tray, are exposed as a result of opening the cover  44 . The lower stage side tray  40  and the upper stage side tray  45  configure a front feeding device  10  ( FIG. 2 ), as “a first feeding unit”, and are an accommodation section that accommodates sheets of paper. 
     The paper ejection reception tray  8  is provided to be able to take on a state (not illustrated in the drawings) of being accommodated in the apparatus main body  2 , and a state ( FIG. 1 ) of protruding on a front side of the apparatus main body  2  as a result a motor, which is not illustrated in the drawings, and as a result of attaining the state of protruding on the front side of the apparatus main body  2 , can receive recording paper sheets that are ejected due to recording being performed. 
     The lower stage side tray  40  and the upper stage side tray  45 , which are capable of accommodating a plurality of recording paper sheets, are a medium accommodation section that accommodates a medium, that is, the medium accommodation section of the printer  1  is configured by a plurality of medium accommodation sections. The lower stage side tray  40  and the upper stage side tray  45 , which is provided above the lower stage side tray  40 , are respectively independently detachable from the apparatus main body  2 . In addition, even if one of the lower stage side tray  40  and the upper stage side tray  45  is in an unmounted state, as long as the other is mounted, it is possible to deliver recording paper sheets from the corresponding tray that is mounted. 
     Additionally, in a state in which the upper stage side tray  45  is mounted in the apparatus main body  2 , the upper stage side tray  45  is provided between a standby position (not illustrated in the drawings), and an abutting position (a position in which feeding is possible:  FIG. 1 ) in a manner in which the upper stage side tray  45  performs sliding displacement due to a tray driving unit, which is not illustrated in the drawings. For example, when a printing job, which supplies from the upper stage side tray  45 , is executed, a control section (not illustrated in  FIGS. 1 and 2 ) of the printer  1  positions the upper stage side tray  45  in the abutting position that is shown in  FIG. 2 . In addition, when a printing job, which supplies from the lower stage side tray  40 , is executed, a control section  48  of the printer  1  positions the upper stage side tray  45  in a retreat position (not illustrated in the drawings). 
     The printer  1  is provided with a tray position detection sensor (not illustrated in the drawings) that detects a sliding position of the upper stage side tray  45 , and the control section of the printer  1  can ascertain whether or not the upper stage side tray  45  is in the position in which feeding is possible or in the retreat position on the basis of signal information that is sent from the corresponding tray position detection sensor. However, in the present embodiment, since the upper stage side tray  45  is driven by a motor, it is possible to ascertain whether or not the abutting position of the upper stage side tray  45  is either side (a side of the position in which feeding is possible or a side of the retreat position) by increasing a current value of the motor on the basis of a motor driving direction. 
     Subsequently, the reference numeral  6  in a rear upper section of the apparatus main body  2  is a cover that is capable of opening and closing, and the feeding of recording paper sheets, which uses the rear feeding device  7 , as “a second feeding unit”, is performed by opening the cover  6 . 
     Next, a paper sheet transport pathway of the printer  1  will be described with reference to  FIG. 2 . As described above, the printer  1  according to the present embodiment is provided with a plurality of paper sheet feeding devices, that is, the front feeding device  10 , as the “first feeding unit”, and the rear feeding device  7 , as the “second feeding unit”. The front feeding device  10  has a configuration that delivers sheets of paper from the lower stage side tray  40  and the upper stage side tray  45 , which are medium accommodation sections that accommodate sheets of paper in a substantially flat manner, and the rear feeding device  7  has a configuration that delivers sheets of paper from a hopper  34 , as a medium setting section, in which sheets of paper are set with an inclined posture. 
     Firstly, in the front feeding device  10 , a feeding roller  9 , which is rotationally driven by a motor  49  ( FIG. 3 ), as a driving source, is provided on the roller support member  11  as a swinging member, which swings with a rotational shaft  12  as the center thereof, and when the upper stage side tray  45  is in the retreat position, delivers a topmost sheet of paper, which is accommodated in the lower stage side tray  40 , from the lower stage side tray  40  by rotating in contact with the corresponding topmost sheet of paper. 
     In addition, when the upper stage side tray  45  is in the abutting position (the position in which feeding is possible:  FIG. 2 ), the feeding roller  9  delivers a topmost sheet of paper, which is accommodated in the upper stage side tray  45 , from the upper stage side tray  45  by rotating in contact with the corresponding topmost sheet of paper. 
     Additionally, in the present embodiment, the rotational shaft  12  configures a swinging axis of a roller support member  11 , and transmits a driving force from a transmission gear  13 , which, as shown in  FIG. 3 , is provided on the rotational shaft  12 , to a target transmission gear (not illustrated in the drawing), which is provided integrally with the feeding roller  9 , via a gear train row  14  by receiving a driving force of the motor  49  ( FIG. 3 ) and rotating. The rotational shaft  12  also simultaneously transmits a driving force for causing the roller support member  11  to swing when transmitting the driving force for causing the feeding roller  9  to rotate. In a case on which the feeding roller  9  rotates in a direction that delivers sheets of paper, a swinging force is applied to the roller support member  11  in the anticlockwise direction (a direction on which the feeding roller  9  comes into contact with a sheet of paper) in  FIG. 2 . Additionally, in the present embodiment, the feeding roller  9  is provided on both sides of the gear train row  14  with the gear train row  14  interposed therebetween. 
     A separation inclined surface  17  is provided in a position that faces a leading end of the lower stage side tray  40  and the upper stage side tray  45 , and separation of the topmost sheet of paper P, which should be fed, and a subsequent sheet of paper P is performed as a result of leading ends of sheets of paper P that are delivered from the lower stage side tray  40  or the upper stage side tray  45  proceeding to a downstream side while in contact with the separation inclined surface  17 . 
     An intermediate roller  18 , which is rotationally driven by a motor, which is not illustrated in the drawings, is provided at a front end of the separation inclined surface  17 , and the sheets of paper are curved and inverted by the intermediate roller  18 , and move toward an apparatus front side. Additionally, the reference numerals  19 A,  19 B and  19 C are driven rollers, which are capable of being driven to rotate, and at least the sheets of paper are sent to the downstream side as a result of being nipped by the driven roller  19 A and the intermediate roller  18 , and nipped by the driven roller  19 B and the intermediate roller  18 . 
     Subsequently, in the rear feeding device  7 , the reference numeral  34  is a hopper, the reference numeral  29  is a feeding roller, and the reference numeral  33  is a separation roller. In this case, when the rear feeding device  7  is described with reference to  FIG. 14 , the hopper  34  is capable of swinging with a swinging pivot point  34   a  of an upper section as a center thereof, and causes the feeding roller  29  to come into pressure contact with sheets of paper that are supported in an inclined posture or separates the feeding roller  29  from the sheets of paper that are supported in an inclined posture as a result of swinging. The feeding roller  29  is provided on the rotational shaft  30 , and the rotational shaft  30  is rotationally driven by the motor  49  ( FIG. 3 ). Additionally, a paper support for extending a paper sheet support surface of the hopper  34  upward is provided on a back surface side of the hopper  34 , but description thereof will be omitted. 
     The separation roller  33  is provided in a holder  38 , which swings with a swinging axis  38   a  as the center thereof, and is capable of rotating in a state in which rotational resistance is being applied thereto. The holder  38  is engaged with the hopper  34 , as shown by the solid lines in  FIG. 14 , is pushed down toward a lower section when the hopper  34  is in a descended posture (a posture in which the sheets of paper are separated from the feeding roller  29 ), and the separation roller  33  is separated from the feeding roller  29 . In contrast to this, when the hopper  34  is in a raised posture (a posture in which the sheets of paper are in pressure contact with the feeding roller  29 ), the holder  38  is pushed up toward an upper section (the virtual lines and reference numeral  38 ′ in  FIG. 14 ) by a biasing force of a biasing unit, which is not illustrated in the drawing, and as a result of this, the separation roller  33  comes into contact with the feeding roller  29  (the virtual lines and reference numeral  33 ′ in  FIG. 14 ). 
     In a state in which the separation roller  33  is in contact with the feeding roller  29  a topmost sheet of paper that should be fed receives a transport force from the feeding roller  29 , is delivered from between the two rollers, and multifeed is prevented as a result of a subsequent sheet of paper, for which there is a concern of multifeeding, remaining in a nipped position between the separation roller  33  and the feeding roller  29 . Additionally, the sheet of paper P that remains in the nipped position between the separation roller  33  and the feeding roller  29  is returned to the top of the hopper  34  as a result of a paper sheet return lever  35  ( FIGS. 10 and 11 ). 
     The sheet of paper P that is delivered by the feeding roller  29  receives the transport force from the intermediate roller  18  in the same manner as the sheets of paper P that are delivered from the front feeding device  10 , and is transported toward the transport driving roller  21 . 
     The abovementioned hopper  34  and the paper sheet return lever  35  are driven by the driving force of the motor  49  ( FIG. 3 ), but this feature will be described later. 
     Returning to  FIG. 2 , the transport driving roller  21 , which is driven by a motor, which is not illustrated in the drawings, and a transport driven roller  22 , which is driven to rotate by being in contrast to the transport driving roller  21 , are provided at a front end of the intermediate roller  18 , and sheets of paper are sent below a recording head  25 , which configures the recording unit, by these rollers. 
     Subsequently, the recording head  25 , which discharges an ink, is provided in a bottom section of the carriage  24 , and the carriage  24  is driven to reciprocate in a main scanning direction (a paper surface front and back direction in  FIG. 2 ) by a motor, which is not illustrated in the drawings. 
     A support member  23  is provided in a position that faces the recording head  25 , and an interval between sheets of paper and the recording head  25  is defined by the support member  23 . Further, an ejection driving roller  26 , which is driven by a motor, which is not illustrated in the drawings, and an ejection driven roller  27 , which is driven to rotate as a result of being in contact with the ejection driving roller  26 , are provided on a downstream side of the support member  23 . The sheets of paper on which recording has been performed by the recording head  25  are ejected toward the paper ejection reception tray  8  that was mentioned above, by these rollers. 
     In the present embodiment, the feeding roller  9  (the front feeding device  10 ), the feeding roller  29  (the rear feeding device  7 ), the intermediate roller  18 , the transport driving roller  21 , and the ejection driving roller  26  a driven by a single motor (the motor  49 :  FIG. 3 ), and furthermore, the motor  49  is controlled by a control section  48  ( FIG. 3 ). In addition, the motor (not illustrated in the drawings) that drives the carriage  24 , and the recording head  25  are also controlled by the control section  48 . 
     2. Driving Force Transmission Pathway 
     Next, a driving force transmission pathway that transmits a driving force from the motor  49  to the front feeding device  10  and the rear feeding device  7  will be described with reference to the drawings form  FIG. 3  onward. 
     In  FIG. 3 , the motor  49  drives the transport driving roller  21 , and the front feeding device  10  and the rear feeding device  7  obtain the driving force of the motor  49  via the transport driving roller  21 . 
     In  FIGS. 3 to 9 , the reference numerals  51  to  63  all show gears, and a driving force is transmitted from the gear  51 , which is provided at an axial end of the transport driving roller  21  to ward each feeding device. As is also shown in  FIG. 6 , a gear  52  meshes together with the gear  51 . The gear  52  includes a shaft section  52   a , and the gear  53  fits together with the shaft section  52   a  in a manner in which the gear  53  is capable of sliding in a rotational axis line direction (the x direction). Additionally, although the gear  53  is capable of sliding in the rotational axis line direction (the x direction) with respect to the gear  52 , the gear  53  fits together with the shaft section  52   a  in a manner in which the gear  53  rotates integrally with the gear  52 . 
     In this instance, the gear  53  can be switched between a state ( FIG. 7 ) of meshing together with the gear  54 , and a state ( FIG. 8 ) of not meshing together with (being separated from) the gear  54  by the switching unit  67  (FIGS.  7  and  8 ). In  FIGS. 7 and 8 , the switching unit  67  is provided with a holder member  68  and a face cam accommodation section  69 . The holder member  68  is a member that causes sliding displacement of the gear  53 , and includes an engagement section  68   a  that is capable of engaging with the carriage  24 . 
     A face cam (not illustrated in the drawings) is accommodated in the face cam accommodation section  69 , and a position of the holder member  68 , that is, a position of the gear  53 , is held by the face cam. Additionally, the face cam is a publicly-known face cam. 
     As shown in  FIGS. 7 and 8 , when the carriage  24  moves to a home position, the carriage  24  engages with the engagement section  68   a  of the holder member  68 , and the holder member  68 , that is, the gear  53 , is displaced. Even if the carriage  24  is separated from the home position thereafter, the holder member  68 , that is, the gear  53 , can be held in a displaced position by the abovementioned face cam, which is not illustrated in the drawings. In the abovementioned manner, by engaging with the carriage  24 , the switching unit  67  switches the rotation of the motor  49  between a transmission state ( FIGS. 6 and 7 ) in which transmission to the front feeding device  10  and the rear feeding device  7  is possible, and an interruption state ( FIG. 8 ) in which the transmission is interrupted. 
     Returning to  FIG. 6 , a one-way clutch mechanism  64  ( FIGS. 4 and 5 ) is provided on an inner side of the gear  54 , and a driving force is transmitted from the gear  54  to the gear  55  via the one-way clutch mechanism  64 . Additionally,  FIGS. 4 and 5  are cross-sectional perspective views of the gear  54 , but hatching is omitted in order to simplify the drawings. 
     The gear  55  meshes together with the gear  57 , which is provided at an axial end of the rotational shaft  12  (the shaft that transmits a driving force to the feeding roller  9 ), that is, the rotational shaft  12  obtains a driving force of the gear  51  (the motor  49 ) via the one-way clutch mechanism  64 . The one-way clutch mechanism  64  is a clutch that only transmits the driving force of the gear  51  (the motor  49 ) to the gear  55  during rotation in one direction, and in the present embodiment, transmits torque to the gear  55  during regular rotation of the motor  49 , that is, during rotation in which the gear  51  transports sheets of paper to the downstream side (during regular rotation of the transport driving roller  21 ). As a result of this, during regular rotation of the motor  49 , the rotational shaft  12 , that is, the feeding roller  9  (the front feeding device  10 ) rotates regularly, and delivers sheets of paper to the downstream side. Further, during counter rotation of the motor  49  (during counter rotation of the transport driving roller  21 ), a driving force of the motor  49  is not transmitted to the rotational shaft  12 , that is, the feeding roller  9  (the front feeding device  10 ). Since the one-way clutch mechanism  64 , which exhibits the abovementioned function, is a publicly-known, general one-way clutch mechanism, detailed description thereof will be omitted. 
     Meanwhile, the gear  54  itself always rotates when the motor  49  (the transport driving roller  21 ) rotates, and a driving force is transmitted from the gear  54  to a sun gear  61  via the gear  58 , the gear  59  and the gear  60 . A planetary gear  62  meshes together with the sun gear  61 , as shown in  FIGS. 3 to 5 , the planetary gear  62  is supported by a holder  65 , and performs planetary motion around the sun gear  61  depending on switching of the transmission direction of the sun gear  61 . The planetary gear  62  is displaced between a mesh position ( FIG. 5 ) of meshing together with a transmission gear  63 , which transmits a driving force to the rear feeding device  7 , and a separation position ( FIG. 4 ) of being separated from the gear  63 , as a result of planetary motion. 
     When the planetary gear  62  is in the separation position, a driving force of the motor  49  (the transport driving roller  21 ) is not transmitted to the driving force transmission pathway after the transmission gear  63 , that is, the rear feeding device  7 . In this instance, during regular rotation of the motor  49  (the transport driving roller  21 ), the sun gear  61  rotates in the clockwise direction in  FIGS. 4 and 5 , and the planetary gear  62  is positioned in the separation position ( FIG. 4 ). Additionally, positional restriction of the separation position of the planetary gear  62  is performed as a result of the holder  65  abutting against a restriction section, which is not illustrated in the drawings. 
     Further, when the motor  49  (the transport driving roller  21 ) is switched to counter rotation from this state, the sun gear  61  rotates in the anticlockwise direction in  FIGS. 4 and 5 , the planetary gear  62  is displaced to the mesh position ( FIG. 5 ) as a result, and therefore, a driving force is transmitted to the rear feeding device  7 . Additionally, in a case of driving the rear feeding device  7 , the rotation speed of the motor  49  is set to be slower than a case of driving the front feeding device  10 . As a result of this, in particular, it is possible to reliably retain the meshing together of the planetary gear  62  and the transmission gear  63 . 
     If the abovementioned configuration is summarized, in a mesh state of the gear  53  and the gear  54 , during regular rotation of the motor  49  (the transport driving roller  21 ), a driving force is transmitted to the front feeding device  10 , and sheets of paper are delivered from the front feeding device  10 . At this time, a driving force is not transmitted to the rear feeding device  7 . 
     In contrast to this, during counter rotation of the motor  49  (the transport driving roller  21 ), a driving force is transmitted to the rear feeding device  7 , and sheets of paper are delivered from the rear feeding device  7 . At this time, a driving force is not transmitted to the front feeding device  10 . 
     Subsequently, the setting of a displacement amount of the planetary gear  62  from the separation position to the mesh position will be described. Firstly, a control mode, which the control section  48  executes, will be described. 
     The control section  48  is provided with a normal feeding mode, which performs state switching of the switching unit  67  ( FIGS. 7 and 8 ) by driving the carriage  24  for each sheet of paper that is delivered when sheets of paper are delivered from the front feeding device  10 , and a continuous feeding mode, which continuously delivers a plurality of sheets of paper from the front feeding device  10  without causing the carriage  24  to engage with the switching unit  67  while retaining the switching unit  67  in the transmission state ( FIG. 7 ). 
     In addition, in the abovementioned normal feeding mode and the continuous feeding mode, the control section  48  is capable of executing a skew correction mode, which causes a leading end of a sheet of paper to follow a nipped position between the transport driving roller  21  and the transport driven roller  22  by switching the rotation of the motor  49  from regular rotation to counter rotation thereof for a predetermined period of time. That is, the skew correction mode is a mode that corrects skew by switching the transport driving roller  21  from regular rotation to counter rotation before a leading end of a sheet of paper passes the intermediate roller  18  and reaches the transport driving roller  21  and the transport driven roller  22 , and causing the leading end of the sheet of paper to abut between the transport driving roller  21  and the transport driven roller  22 . 
     In this instance, when the transport driving roller  21  (the motor  49 ) is switched from regular rotation to counter rotation, the planetary gear  62  moves toward the mesh position ( FIG. 5 ) from the separation position ( FIG. 4 ). At this time, if the planetary gear  62  moves to the mesh position ( FIG. 5 ), a driving force is transmitted to the rear feeding device  7 , and a sheet of paper is unintentionally fed from the rear feeding device  7  as a result. 
     In such an instance, in the present embodiment, a movement amount of the planetary gear  62  when the motor  49  is counter rotated for a predetermined period of time is set to be smaller than a movement amount to reach the mesh position ( FIG. 5 ) from the separation position ( FIG. 4 ). 
     In  FIG. 9 , the reference numeral a shows a swing angle of the holder  65  (the planetary gear  62 ) of the planetary gear  62  moving from the separation position (the reference numeral  62  and the solid line) to the mesh position (the reference numeral  62 ′ and the virtual line). In the skew correction mode, a swing angle of the holder  65  (the planetary gear  62 ) when the motor  49  is counter rotated for a predetermined period of time is set to be smaller than the angle α. 
     As a result of the above, even if the motor  49  is counter rotated for a predetermined period of time during execution of the skew correction mode, the driving target does not switch from the front feeding device  10  to the rear feeding device  7 . As a result of this, it is possible to perform suitable feeding control without a sheet of paper from the rear feeding device  7  being unintentionally sent during the skew correction mode. 
     Additionally, the abovementioned counter rotation of the motor  49  for a predetermined period of time can be managed by a pulse number (a step number) that is delivered from an encoder, which determines the rotation of the motor  49 , and which is not illustrated in the drawings. 
     The following is a summary of the configuration of the invention that is described above. The printer  1  is provided with the recording head  25 , as a recording unit that performs recording on sheets of paper, and a transport driving roller  21  which transports sheets of paper, and which rotates in a direction that transports the sheets of paper to a downstream side when the motor  49  is regularly rotated, and rotates in direction that transports the sheets of paper to an upstream side when the motor  49  is counter rotated. In addition, the printer  1  is provided with the front feeding device  10 , which is capable of accommodating the sheets of paper, and which delivers the sheets of paper toward the transport driving roller  21  when the motor  49  is regularly rotated by obtaining a driving force from the motor  49  (the transport driving roller  21 ), and the rear feeding device  7 , which is capable of accommodating the sheets of paper, and which delivers the sheets of paper toward the transport driving roller  21  when the motor  49  (the transport driving roller  21 ) is counter rotated by obtaining a driving force from the motor  49  (the transport driving roller  21 ). 
     In addition, the printer  1  is provided with the sun gear  61 , which rotates as a result of receiving the driving force of the motor  49  (the transport driving roller  21 ), and the planetary gear  62  that performs planetary motion around the sun gear  61 . Further, the printer  1  is provided with a planetary gear mechanism that is provided with a configuration that is positioned in a separation position, in which the planetary gear  62  is separated from the transmission gear  63  that transmits a driving force to the rear feeding device  7 , when the motor  49  (the transport driving roller  21 ) is regularly rotated, and that is positioned in a mesh position, in which the planetary gear  62  meshes together with the transmission gear  63 , when the motor  49  (the transport driving roller  21 ) is counter rotated. 
     Further, the control section  48 , which controls the rotation of the motor  49  (the transport driving roller  21 ) is capable of executing a skew correction mode, which causes a leading end of a sheets of paper to follow the transport driving roller  21  by switching the rotation of the motor  49  from regular rotation to counter rotation thereof for a predetermined period of time in a feeding mode, which feeds the sheets of paper from the front feeding device  10 , and a movement amount of the planetary gear  62  when the motor  49  (the transport driving roller  21 ) is counter rotated for a predetermined period of time is set to be smaller than a movement amount to reach the mesh position from the separation position. 
     Additionally, in the abovementioned embodiment, an example in which the invention adopts the front feeding device  10  as the “first feeding unit” and the rear feeding device  7  as the “second feeding unit” is described, but, for example, the invention can adopt a configuration in which a plurality of front feeding devices  10  are provided in an up-down direction (a multi-tray configuration), and for example, a two-stage tray configuration. 
     3. Rear Feeding Device 
     Subsequently, the configuration of the rear feeding device  7  will be described in detail with reference to the drawings from  FIG. 10  onwards. 
     Firstly, the rear feeding device  7  will be outlined with reference to  FIGS. 10 and 11 . In  FIGS. 10 and 11 , reference numeral  73  is a gear that obtains a driving force via a one-time clutch mechanism  69 , the gear  73  is fixed to a shaft  37 , rotates once only as a result of the function of the one-time clutch mechanism  69  during a feeding action, and transmits a driving force to various constituent elements of the rear feeding device  7 . Additionally, the one-time clutch mechanism  69  will be further described later. In  FIG. 11 , the illustration of the face cam accommodation section  69  is omitted. 
     A gear  74  is fixed to the shaft  37 , and a driving force is transmitted from the gear  74  to the gear  75 . A cam section  75   a  is formed on the gear  75 , the cam section  75   a  engages with an engagement section  36   a , which is formed on a shaft  36 , and causes the shaft  36  to rotate. That is, the cam section  75   a  causes the paper sheet return lever  35  to rotate. 
     In addition, a gear  76  meshes together with the gear  74 , and a gear  79  meshes together with the gear  76 . The gear  79  is provided in an unfixed manner so as to capable of mutually rotating with respect to the rotational shaft  30 . A cam section  79   a  is formed on the gear  79 , the cam section  79   a  engages with the hopper  34 , and causes the hopper  34  to swing. 
     The driving force transmission from the gear  74  to the gear  75 , and from the gear  74  to the gear  79  is set to a reduction ratio of 1:1, that is, when the gear  73  (the shaft  37 ) rotates a single time, the abovementioned gears rotate a single time according to the rotation of the gear  73  (the shaft  37 ) as a result of the function of the one-time clutch mechanism  69 . 
     Meanwhile, a gear  77  meshes together with the gear  73 , and a gear  78  meshes together with the gear  77 . The gear  78  is fixed to an axial end of the rotational shaft  30 , and is a gear that causes the rotational shaft  30 , that is, the feeding roller  29 , to rotate. In this instance, the driving force transmission to the gear  73 , the gear  77  and the gear  78  is set to a reduction ratio of 1:α (α&gt;1), that is, when the gear  73  (the shaft  37 ) rotates a single time, the rotational shaft  30 , that is, the feeding roller  29 , rotates more than a single time as a result of the function of the one-time clutch mechanism  69 . 
     If the abovementioned configuration is summarized, the rear feeding device  7  is provided with the feeding roller  29  that delivers the sheets of paper, the hopper  34 , which supports the sheets of paper in an inclined posture, which is capable of switching between a state that causes the feeding roller  29  to come into pressure contact with the sheets of paper as a result of swinging, and a state that causes the sheets of paper to be separated from the feeding roller  29 , the cam  79   a , which is a cam that engages with the hopper  34  and rotates by obtaining a driving force from the transmission gear  73 , and which executes state switching of the hopper  34  a single time during a single rotation action, and a gear group (the gears  73 ,  77  and  78 ), which is a unit that transmits a driving force from the transmission gear  73  to the feeding roller  29 , and which causes the feeding roller  29  to rotate a plurality of times during a single rotation action of the cam  79   a . As a result of this, it is possible to reduce the diameter of the feeding roller  29 , and therefore, it is possible to achieve miniaturization of the apparatus. 
     Next, the one-way latch mechanism  28  that the rear feeding device  7  is provided with will be described. As shown in  FIGS. 12 and 13 , the one-way latch mechanism  28  is configured to be provided with a fixed member  31 , which is fixed to the rotational shaft  30 , and a movable member  32 , which fits together with the rotational shaft  30  in a manner in which the movable member  32  is capable of mutually rotating with respect to the rotational shaft  30 . 
       FIG. 12  shows a state in which the rotational shaft  30  is driven. The arrow shows a rotational direction, and in this state, a hook  31   a , which is formed on the fixed member  31 , meshes together with a hook  32   a , which is formed on the movable member  32 , a stopper  32   b , which is formed on the movable member  32 , engages with a protrusion  29   a  of the feeding roller  29 , and as a result of this, a rotational driving force is transmitted to the feeding roller  29 . 
       FIG. 13  shows a state (a rotation cessation state) in which the rotational shaft  30  is not being driven, and a state on which the feeding roller  29  driven around by sheets of paper that are transported by the transport driving roller  21  (the arrow). In this state, the protrusion  29   a  of the feeding roller  29  is engaged with a stopper  32   c  of the movable member  32 , and the movable member  32  is rotated, but the hook  32   a , which is formed on the movable member  32  is separated from the hook  31   a , which is formed on the fixed member  31 , and the feeding roller  29  and the movable member  32  can rotate independently from the rotational shaft  30  and the fixed member  31 . 
     If the abovementioned configuration is summarized, the rear feeding device  7  is provided with the feeding roller  29  that delivers the sheets of paper, the rotational shaft  30  on which the feeding roller  29  is provided, and the one-way latch mechanism  28  that allows idling of the feeding roller  29  with respect to the rotational shaft  30  when the sheets of paper that is delivered from the rear feeding device  7  are transported to the downstream side by the transport driving roller  21 . As a result of this, it is possible to eliminate or reduce a load that the feeding roller  29  applies to the sheets of paper when the sheets of paper that are delivered from the rear feeding device  7  are transported to the downstream side by the transport driving roller  21 , and therefore, it is possible to suitably perform medium transport using the transport driving roller  21 . 
     Next, the one-time clutch mechanism  69  will be described. The one-time clutch mechanism  69  is provided with a gear  70 , which, as shown in  FIGS. 3 and 10 , meshes together with the gear  63 , a rotating body  72 , which, as shown in  FIG. 10 , is fixed to an axial end of the rotating shaft  37 , and a swinging ring  71 , which is provided so as to be capable of swinging with respect to the rotating body  72 . 
     The one-time clutch mechanism  69  generally switches between a state in which driving is transmitted from the gear  70  to the rotating body  72  (the rotating shaft  37 ) as a result of the swinging ring  71  swinging with respect to the rotating body  72 , and a contrasting state in which the transmission is interrupted. 
       FIG. 15  is a view that shows a relationship between the swinging ring  71  and the gear  70 , and hereinafter, description will be given with reference to  FIGS. 10 and 15 . 
     Firstly, in a driving transmission state, the gear  70 , the swinging ring  71 , the rotating body  72 , and the rotating shaft  37  are a rotating body that rotates integrally with the same axial center. Among these components, the swinging ring  71  is provided on the rotating body  72  in a manner in which the swinging ring  71  is capable of swinging with a swinging center  71   a  as the center thereof, and as a result of this swinging, a clutch  71   b , which is provided on the inner periphery thereof, switches between a state of meshing together with a transmission gear  70   a  ( FIG. 15 ), and a state of being separated (not illustrated in the drawings). 
     An engagement protrusion  71   c  is formed on the outer periphery of the swinging ring  71 , and the engagement protrusion  71   c  is capable of engaging with a lever, which is not illustrated in the drawings. When the engagement protrusion  71   c  is in a non-engaged state with respect to the lever, which is not illustrated in the drawings, as shown in  FIG. 14 , a driving transmission state is attained as a result of the clutch  71   b  engaging with the transmission gear  70   a . Additionally, the swinging ring  71  is biased in a swinging manner in a direction in which the clutch  71   b  meshes together with the transmission gear  70   a  by a biasing unit, which is not illustrated in the drawings. When the engagement protrusion  71   c  engages with the lever, which is not illustrated in the drawings, a driving interruption state is attained as a result of the swinging ring  71  swinging in a direction in which the clutch  71   b  becomes separated from the transmission gear  70   a . The basic configuration of the abovementioned clutch is the same as that of technology of the related art. 
     The characterizing feature of the present embodiment is that a plurality (two in the present embodiment) of the clutches  71   b  is provided. That is, as was described with reference to  FIG. 11 , a reduction ratio of the driving force transmission from the gear  73  to the gear  77  and the gear  78  is set to 1:α (α&gt;1) so that the rotational shaft  30 , that is, the feeding roller  29 , rotates more than a single time when the gear  73  (the shaft  37 ) rotates a single time. Accordingly, a reaction force (torque) that the one-time clutch mechanism  69  is subjected to from the feeding roller  29  side is large, and there is a high risk that the clutch  71   b  will be damaged. 
     However, since a plurality of the clutches  71   b  are provided in the manner described above, it is possible to effectively suppress damage of the clutches  71   b . Additionally, in the example that is shown in  FIG. 15 , two clutches  71   b  are provided, but more may be provided. 
     In addition, for the same reason, in addition to providing a plurality of clutches  71   b , it is suitable to increase the tooth thickness of the clutch  71   b.    
     In addition, as shown in  FIG. 16 , the strength of the clutch  71   b  may be improved by providing a flange  71   d  integrally with the clutch  71   b.    
     The entire disclosure of Japanese Patent Application No. 2015-028642, filed Feb. 17, 2015 is expressly incorporated by reference herein.