Abstract:
The invention describes an image recording device having a sheet supplying device that supplies sheets. The sheet supplying device has a first tray and a second tray that hold sheets, and a first and second shaft positioned over the first and second trays. A first rotating member contacts a sheet in the first tray, and a second rotating member contacts a sheet in the second tray. A first arm extends from the first shaft to the first rotating member, and a second arm extends from the second shaft to the second rotating member. A transmission device is coupled to the first arm member and the second arm member, and transmits selectively a rotational drive force from the first shaft to either the first or second rotating members. A recording unit records an image on the sheet supplied by the sheet supplying device.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims priority from Japanese Patent Application No. 2007-049614, filed on Feb. 28, 2007, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to sheet supplying devices configured to feed sheet members held in each of a plurality of sheet trays in a predetermined direction and image recording apparatuses including the sheet supplying devices. 
     2. Description of Related Art 
     Image recording apparatuses, such as printers, mount sheet supplying devices thereon. A sheet supplying device includes a sheet tray configured to hold a stack of recording sheets. A sheet supplying device further includes a feed roller configured to feed recording sheets stacked in a sheet tray while separating the recording sheets. The feed roller rotates while contacting an upper surface of a stack of recording sheets in the sheet tray, to feed a recording sheet from the sheet tray. 
     Known paper feeding devices may have two sheet trays that are arranged vertically in a stepped manner. Feed rollers are provided for each of two sheet trays. In known image recording apparatuses, upper and lower sheet trays are positioned below the drive shaft. A transmission mechanism is configured to transmit rotation of the drive shaft in one direction to the upper tray feed rollers. The transmission mechanism also is configured to transmit rotation of the drive shaft in an opposite direction to the lower tray feed rollers positioned near each end of the drive shaft. In the transmission mechanism, the rotating shaft is positioned above the drive shaft, and transmission gears are mounted to the rotating shaft, which increase the size of the transmission mechanism in the vertical direction. In other known transmission mechanism and sheet tray arrangements, a path must be maintained to feed a recording sheet below and above the drive shaft, which path increases the size of the paper feeding device. 
     SUMMARY OF THE INVENTION 
     In an embodiment of the invention, a sheet supplying device configured to supply a sheet member, the sheet supplying device comprising a first tray and a second tray, each configured to hold at least one sheet member, a first shaft and a second shaft, each positioned over both of the first tray and the second tray, a first rotating member contacting the at least one sheet member held in the first tray, a second rotating member contacting the at least one sheet member held in the second tray, a first arm member extending from the first shaft to the first rotating member, a second arm member extending from the second shaft to the second rotating member, and a transmission device coupled to each of the first arm member and the second arm member and configured to transmit selectively a rotational drive force from the first shaft to one of the first rotating member and the second rotating member. 
     In an embodiment of the invention, an image recording apparatus comprises a sheet supplying device configured to supply a sheet member, the sheet supplying device comprising a first tray and a second tray, each configured to hold at least one sheet member, a first shaft and a second shaft, each positioned over both of the first tray and the second tray, a first rotating member contacting the at least one sheet member held in the first tray, a second rotating member contacting the at least one sheet member held in the second tray, a first arm member extending from the first shaft to the first rotating member, a second arm member extending from the second shaft to the second rotating member, and a transmission device coupled to each of the first arm member and the second arm member and configured to transmit selectively a rotational drive force from the first shaft to one of the first rotating member and the second rotating member, and a recording unit configured to record an image on the sheet member supplied by the sheet supplying device. 
     Other objects, features, and advantages will be apparent to persons of ordinary skill in the art from the following detailed description of the invention and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention, needs satisfied thereby, and the objects, features, and advantages thereof, reference now is made to the following description taken in connection with the accompanying drawings. 
         FIG. 1  is a perspective view of a multi-function device (MFD), according to an embodiment of the invention. 
         FIG. 2  is a cross-sectional view of a printer section of the MFD showing an inner structure of the printer section, according to an embodiment of the invention. 
         FIG. 3A  is a plan view of an upper sheet tray, according to an embodiment of the invention. 
         FIG. 3B  is a cross-sectional view of the upper sheet tray taken along the line IIIb-IIIb of  FIG. 3A . 
         FIG. 4A  is a plan view of a lower sheet tray, according to an embodiment of the invention. 
         FIG. 4B  is a cross-sectional view of the lower sheet tray taken along the line IVb-IVb of  FIG. 4A . 
         FIG. 5  is a plan view of a sheet feeder, according to an embodiment of the invention. 
         FIG. 6  is a cross-sectional view of the sheet feeder taken along the line VI-VI of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     An embodiment of the invention and its features and technical advantages may be understood by referring to  FIGS. 1-6 , like numerals being used for like corresponding portions in the various drawings. 
     Referring to  FIG. 1 , a multi-function device (“MFD”)  1  may comprise a printer section  2  and a scanner section  3 . MFD  1  may have a printing function, a scanner function, a copying function and a facsimile function. MFD  1  may have a hexahedron shape, the width and depth of which may be greater than its height. An upper portion of MFD  1  may include a scanner section  3 , which may be configured as a flat bed scanner. As shown in  FIG. 1 , MFD  1  may include a document cover  5  as a top panel. Document cover  5  may pivot about a hinge (not shown) positioned at a rear side of scanner section  3 . A platen glass and an image sensor (not shown) may be positioned under document cover  5 . An image on a document placed on the platen glass may be read by the image sensor. 
     MFD  1  may include a printer section  2  at its lower portion. Printer section  2  may record an image or text, or both, on a recording sheet, as an example of a sheet member, based on print data, e.g., image data or text data input from an external device, and image data read by scanner section  3 . Printer section  2  may have an opening  10  at a front face of MFD  1 . As shown in  FIGS. 1 and 2 , an upper sheet tray  12 , a lower sheet tray  13 , and an output tray  14  may be positioned vertically in opening  10 . Trays  12 ,  13 ,  14  may be assembled into a sheet cassette  35 . 
     Each of upper and lower sheet trays  12 ,  13  may hold a stack of recording sheets. Upper sheet tray  12  and lower sheet tray  13  may be configured to hold different sizes or weights of sheets. Specifically, upper sheet tray  12  may hold recording sheets with the size of, e.g., postcards, standard photos, and business cards. Lower sheet tray  13  may hold recording sheets with a size of B5 or larger, e.g., A4 and letter sizes. Lower sheet tray  13  may be configured to be unable to hold recording sheets, such as postcards, smaller than B5 sizes. The sheet size held by lower sheet tray  13  also may be determined based on whether a first sheet feeding mechanism  33 A is configured to feed recording sheets from lower sheet tray  13 . More specifically, if first sheet feeding mechanism  33 A is not configured to feed recording sheets from lower sheet tray  13 , the size of such recording sheets may not be held even though the recording sheets could be held in lower sheet tray  13 . 
     When an image, or text, or both, is recorded in printer section  2  on a recording sheet fed from upper or lower sheet tray  12 ,  13 , the sheet may be ejected onto output tray  14 . Printer section  2  and scanner section  3  may execute instructions input from a control panel  4  positioned on an upper front portion of MFD  1  or instructions transmitted from a computer via a printer driver or a scanner driver. 
     Referring to  FIGS. 2 to 4B , printer section  2  may comprise a sheet feeder  6 , including sheet cassette  35  and a sheet feeding mechanism  33 . Sheet cassette  35  may hold a plurality of types of recording sheets. Sheet cassette  35  may comprise upper sheet tray  12 , lower sheet tray  13 , and output tray  14 . Sheet feeding mechanism  33  may be configured to selectively feed recording sheets held in upper sheet tray  12  or lower sheet tray  13 . As shown in  FIG. 2 , upper sheet tray  12  may be positioned above lower sheet tray  13 . In other words, upper sheet tray  12  and lower sheet tray  13  may be stacked in the vertical direction. A first feed roller  26  may be positioned at an upper side of lower sheet tray  13 . A second feed roller  25  may be positioned at an upper side of upper sheet tray  12 . Upper sheet tray  12  may be formed of synthetic resin. As shown in  FIGS. 3A and 3B , a pair of sheet guides  37  and a rear guide  38  may be positioned on an upper surface of upper sheet tray  12 . 
     Sheet guides  37  may be configured to align edges of recording sheets, which are loaded on upper sheet tray  12 , in a width, e.g., lateral, direction of the recording sheets. Sheet guides  37  may be positioned on an upper surface of upper sheet tray  12  at a downstream side in the sheet feeding direction, e.g., the direction of arrow  43 , at a side closer to an inclined plate  20 . Sheet guides  37  may slidably move on an upper surface of upper sheet tray  12  along a width, e.g., lateral, direction of upper sheet tray  12 . Recording sheets may be positioned between sheet guides  37 . Positions of recording sheets, which are loaded onto upper sheet tray  12 , may be regulated by a pair of sheet guides  37 , with respect to their width, e.g., lateral, direction. More specifically, sheet guides  37  may regulate the positions of recording sheets loaded onto upper sheet tray  12  so as to substantially align a center of the recording sheets with respect to their width, e.g., lateral, direction, with a predetermined reference position. The center of upper sheet tray  12  in its width, e.g., lateral, direction may be set as the reference position. 
     A pair of sheet guides  37  may be coupled to each other by a known coupling mechanism, such as a rack and pinion mechanism. As one of sheet guides  37  may be slidably moved in one direction, the other sheet guide  37  may be slidably moved in an opposite direction. 
     Rear guide  38  may be configured to align rear or trailing ends of recording sheets loaded onto upper sheet tray  12 . Rear guide  38  may be supported at an upper surface of upper sheet tray  12  so as to slide in the sheet feeding direction, e.g., the direction of arrow  43 . Rear guide  38  may be configured to stop at positions corresponding to predetermined sheet sizes, e.g., the sizes of postcards, photographs, and business cards. 
     A friction pad  41  may be positioned between sheet guides  37  at generally a middle portion of upper sheet tray  12  in its width, e.g., lateral, direction. Friction pad  41  may be positioned on an upper surface of upper sheet tray  12  at a position to contact second feed roller  25 . Friction pad  41  may be formed of material having a high friction coefficient, such as cork and felt. Second feed roller  25  may contact directly friction pad  41  or indirectly contact friction pad  41  via recording sheets. With friction pad  41 , when second feed roller  25  rotates, for example, with a reduced amount of remaining recording sheets in upper sheet tray  12 , frictional force in the sheet feeding direction, e.g., the direction of arrow  43 , may be applied from second feed roller  25  to an upper part of a stack of recording sheets and frictional force in the opposite direction may be applied from friction pad  41  to a lower part of a stack of recording sheets. Thus, a situation where a plurality of recording sheets is fed simultaneously may be reduced. 
     Upper sheet tray  12  may have two openings  39 . Each opening  39  may be positioned on an upper surface of upper sheet tray  12  at a downstream side in the sheet feeding direction. More specifically, openings  39  may be positioned near ends of upper sheet tray  12  in its width, e.g., lateral, direction and outside sheet guides  37 . With such arrangements of openings  39 , a slidable range of sheet guides  37  is limited to an area defined between openings  39 . As shown in  FIG. 3A , each opening  39  may be of a rectangular shape elongated in a longitudinal direction of upper sheet tray  12 , e.g., a right and left direction as shown in  FIG. 3A . Each opening  39  may pass through from an upper surface of upper sheet tray  12  to its lower surface. A swing arm  28  may insert into each opening  39  from an upper side to a lower side of upper sheet tray  12 . 
     As shown in  FIGS. 4A and 4B , a pair of sheet guides  45  may be positioned on an upper surface of lower sheet tray  13 . Sheet guides  45  may be supported at an upper surface of lower sheet tray  13  so as to slidably move in a width, e.g., lateral, direction of lower sheet tray  13 . Recording sheets may be placed between sheet guides  45 . Each sheet guide  45  may be positioned near an end of an upper surface of lower sheet tray  13  in its width, e.g., lateral, direction, so as to slidably move inwardly by a predetermined distance to a predetermined position. A coupling mechanism of sheet guides  45  is similar to that of sheet guide  37 , and further description with respect to sheet guides  45  is omitted here. 
     Friction pads  46  configured similar to friction pad  41  may be positioned on an upper surface of lower sheet tray  13 . Friction pads  46  may be positioned below openings  39  of upper sheet tray  12 . Broken lines in  FIGS. 4A and 4B  show openings  39 . Friction pads  46  may be positioned on an upper surface of lower sheet tray  13  at positions to contact first feed rollers  26 . Because friction pads  46  are similar to friction pad  41 , further description with respect to friction pads  46  is omitted here. 
     As shown in  FIGS. 3A to 4B , inclined plates  20 ,  22  may be positioned in upper sheet tray  12  and lower sheet tray  13 , respectively. Each inclined plate  20 ,  22  may be positioned at an angle such that its downstream end in the sheet feeding direction, e.g., the direction of arrow  43 , inclines toward a rear side of MFD  1 . An inner surface of each inclined plate  20 ,  22  may function as a guide surface to guide recording sheets to a sheet feeding path  23 , as shown in  FIG. 2 . Each inclined plate  20 ,  22  may have a plurality of separation teeth  19 ,  21 , respectively that extend from a middle portion of an inner surface of inclined plate  20 ,  22 . Separation teeth  19 ,  21  may be disposed along the sheet feeding direction. When leading ends of a plurality of recording sheets, which are fed at one time from sheet tray  12 ,  13 , contact inclined plates  20 ,  22 , separation teeth  19 ,  21  may separate the recording sheets to guide a topmost recording sheet to sheet feeding path  23 . 
     As shown in  FIG. 2 , sheet feeding path  23  may be positioned so as to extend upward from a rear side of sheet cassette  35 , e.g., a downstream side of cassette  35  in the sheet feeding direction. As shown in  FIG. 1 , sheet feeding path  23  may extend upward from inclined plates  20 ,  22  and make a curve toward a side in which opening  10  is positioned. Thus, sheet feeding path  23  may extend from a rear side of MFD  1  to its front side, reaching output tray  14  via a recording unit  24 . When a recording sheet fed from sheet tray  12  or  13  is conveyed to sheet feeding path  23 , the sheet may be guided, so as to make a U-turn from a lower side to an upper side, to a platen  48 . Recording unit  24  may perform an image recording onto the recording sheet. Then, the sheet may eject onto output tray  14 . 
     Platen  48  may be positioned directly above sheet feeding mechanism  33 . Platen  48  may have a supporting surface enough wide to support recording sheets in their width, e.g., lateral, direction. Recording unit  24  may be positioned above platen  48 , and may comprise a carriage  50  and recording heads  51 , which may be mounted on carriage  50 . Recording heads  51  may be positioned according to the color of ink contained therein. A belt driving mechanism (not shown) may reciprocate carriage  50  at a predetermined interval, in a width, e.g., lateral, direction of platen  48 , while being guided by a guide rail and a guide shaft (not shown). 
     Roller pairs  54 ,  55  may be positioned upstream and downstream of platen  48  in the sheet feeding direction. Each roller pair  54 ,  55  may comprise a roller that is driven by a motor and a pinch roller that is pressed against and driven by the roller. Roller pair  54  may nip, e.g., sandwich, a recording sheet fed along sheet feeding path  23 , to convey the recording sheet onto platen  48 . Roller pair  55  may hold the recording sheet having an image recorded thereon to convey the recording sheet to output tray  14 . Roller pairs  54 ,  55  may be driven intermittently according to a predetermined amount of rotation. Thus, the recording sheet placed on platen  48  may be fed by predetermined amounts, while being stopped intermittently. While rotation of roller pairs  54 ,  55  is stopped, recording unit  24  may be reciprocated in a lateral direction of the recording sheet, and recording heads  51  may selectively eject color ink from their nozzles. A color image may be recorded onto the recording sheet, starting from its leading end and moving toward its trailing end. The recorded sheet may eject onto output tray  14 . 
     For simplicity in illustration, output tray  14  is omitted in  FIGS. 5 and 6 . Sheet feeding mechanism  33  may comprise a second sheet feeding mechanism  33 B configured to feed recording sheets held in upper sheet tray  12  and a first sheet feeding mechanism  33 A configured to feed recording sheets held in lower sheet tray  13 . First sheet feeding mechanism  33 A may comprise first feed roller  26 , a first swing arm  28 , a drive force transmission mechanism  31 , and a drive shaft  29 . Second sheet feeding mechanism  33 B may comprise second feed roller  25 , a second swing arm  27 , a drive force transmission mechanism  30 , and a supporting shaft  32 . 
     Referring to  FIG. 2 , shafts  29 ,  32  may be positioned above sheet cassette  35  and below platen  48 . Drive shaft  29  may extend across MFD  1  in its width, e.g., lateral, direction, and may be supported rotatably by a body frame of MFD  1 . As shown in  FIG. 5 , first sheet feeding mechanisms  33 A may be connected to drive shaft  29  at a portion near each end of drive shaft  29 . Supporting shaft  32  may be positioned parallel to drive shaft  29 . Supporting shaft  32  may be supported rotatably by the body frame at a middle portion of MFD  1  in its width, e.g., lateral, direction. Second sheet feeding mechanism  33 B may be connected to a generally a central portion of supporting shaft  32  in its axial direction. Second sheet feeding mechanism  33 B may be positioned between first feeding mechanisms  33 A. 
     A transmission gear  70  may be mounted on an end of drive shaft  29 . Transmission gear  70  may engage a transmission gear  72 , which may be connected directly to an output shaft of a motor  71 . When motor  71  is driven, a drive force, e.g., rotational torque, from motor  71  may be transmitted to drive shaft  29  via transmission gears  72 ,  70  to rotate drive shaft  29  in a predetermined direction. Motor  71  may be configured to rotate clockwise or counterclockwise and may be controlled by a motor driver. 
     As shown in  FIG. 5 , with respect to second sheet feeding mechanism  33 B, second swing arm  27  may comprise two plate members  75  formed of a resin material. More specifically, second swing arm  27  may be configured such that plate members  75  face each other with a predetermined distance therebetween. An end of second swing arm  27  may be supported pivotably by supporting shaft  32 . More specifically, supporting shaft  32  may support second swing arm  27  to position arm  27  at a substantially middle portion of upper sheet tray  12  in its lateral direction. With such a structure, second swing arm  27  may pivot about supporting shaft  32  at a substantially middle portion of upper sheet tray  12  in its width, e.g., lateral, direction. 
     As shown in  FIG. 6 , second swing arm  27  may extend from supporting shaft  32  toward a substantially middle portion of the upper surface of upper sheet tray  12  in its lateral direction. Second feed roller  25  may be supported rotatably at an end of second swing arm  27 . More specifically, second feed roller  25  may be mounted, via a one-way clutch  80 , to a shaft  78  that is supported rotatably at an end of second swing arm  27 . Thus, second feed roller  25  may be positioned at a middle portion of the upper surface of upper sheet tray  12  in its width, e.g., lateral, direction. Second feed roller  25  may be positioned between plate members  75 . A roller surface of second feed roller  25  may be covered with a rubber member to cause high friction when second feed roller  25  contacts a recording sheet. 
     Drive force transmission mechanism  30  may comprise transmission gears  77 ,  73 ,  79  and two intermediate gears  74 . Transmission gear  77  may be fixed to drive shaft  29 . When drive shaft  29  rotates, transmission gear  77  may rotate in the same direction as drive shaft  29 . Transmission gear  73  may be fixed to supporting shaft  32  inside plate member  75 . When transmission gear  73  rotates, supporting shaft  32  may rotate in the same direction as transmission gear  73 . Transmission gear  73  may engage with transmission gear  77 . As drive shaft  29  rotates, drive force in the direction opposite to the rotation of drive shaft  29  may be transmitted to transmission gear  73 . Transmission gear  79  may be fixed to shaft  78  inside plate member  75 . When transmission gear  79  rotates, shaft  78  may rotate in the same direction as transmission gear  79 . Two intermediate gears  74  may be positioned between transmission gears  79 ,  73 . As shown in  FIG. 6 , each intermediate gear  74  may be supported rotatably by a shaft  76  that may be positioned on plate member  75 . A gear train from transmission gear  77  to transmission gear  79 , including transmission gear  73  and intermediate gears  74 , may be positioned along second swing arm  27 . Drive force input to drive shaft  29  may be transmitted to shaft  78  of second feed roller  25  via transmission gears  77 ,  73 , intermediate gears  74  and transmission gear  79 . 
     Drive force transmission mechanism  30  may be configured to transmit drive force from drive shaft  29  to shaft  78  of second feed roller  25  via a plurality of, e.g., five, gears. Drive force in the same direction as the rotating direction of drive shaft  29 , e.g., drive force in the direction opposite to the rotating direction of supporting shaft  32 , may be transmitted to shaft  78  of second feed roller  25 . Shaft  78  may be rotated in the same direction as the rotating direction of drive shaft  29  and in the opposite direction to the rotating direction of supporting shaft  32 . 
     Drive force transmission mechanism  30  may comprise a one-way clutch  80 . One-way clutch  80  may be fitted into an inner hole of second feed roller  25 . One-way clutch  80  may be configured to transmit drive force to second feed roller  25  when the drive force to feed a recording sheet in the sheet feeding direction, e.g., the direction indicated by arrow  43 , is transmitted to shaft  78 . One-way clutch  80  also may be configured to slip, e.g., not transmit drive force, to second feed roller  25  when the drive force to feed a recording sheet in a direction opposite to the sheet feeding direction is transmitted to shaft  78 . As shown in  FIG. 6 , when drive shaft  29  is rotated in the clockwise direction, drive force transmitted from drive shaft  29  to shaft  78  may be transmitted to second feed roller  25  via one-way clutch  80 . At this time, transmission gear  73  may rotate in a counterclockwise direction, such that second swing arm  27  supported pivotably by supporting shaft  32  may be urged in a direction approaching a bottom plate of upper sheet tray  12 . When drive shaft  29  is rotated in the counterclockwise direction, drive force in the counterclockwise direction transmitted to shaft  78  via gears from drive shaft  29  may be interrupted by one-way clutch  80 . Therefore, the drive force may not be transmitted to second feed roller  25 . At this time, transmission gear  73  may rotate clockwise, so that second swing arm  27  supported pivotably by supporting shaft  32  may be urged in a direction away from the bottom plate of upper sheet tray  12 . In this case, recording sheets in upper sheet tray  12  may not be fed but held in tray  12 . 
     Second swing arm  27  may be urged in a direction approaching the bottom plate of upper sheet tray  12  by a force of its own weight, a force of the weights of second feed roller  25  and drive force transmission mechanism  30 , and a force of a spring (not shown). When the roller surface of second feed roller  25  contacts a recording sheet in upper sheet tray  12 , second swing arm  27  may stop. As drive force in the direction of feeding a recording sheet, e.g., the direction of arrow  43  is transmitted to second feed roller  25  with second swing arm  27  stopped, friction force may be generated between the roller surface of second feed roller  25  and a recording sheet, and the recording sheet may be fed in the sheet feeding direction. In other words, friction force may be applied to a recording sheet as a feeding force to feed the recording sheet in the sheet feeding direction. 
     As shown in  FIG. 5 , with respect to first sheet feeding mechanism  33 A, each first swing arm  28  may comprise two plate members  85  formed of a resin material. More specifically, first swing arm  28  may be configured such that plate members  85  face each other with a predetermined distance therebetween. An end of each first swing arm  28  may be supported pivotably by drive shaft  29 . More specifically, drive shaft  29  may support each first swing arm  28  to position each arm  28  near an end of lower sheet tray  13  in its width, e.g., lateral, direction. 
     As shown in  FIG. 6 , each first swing arm  28  may extend from drive shaft  29  toward the upper surface of lower sheet tray  13  through relevant opening  39  of upper sheet tray  12 . Each first swing arm  28  may pivot about drive shaft  29  at a position near an end of lower sheet tray  13  in its width, e.g., lateral, direction. First feed roller  26  may be supported rotatably at an end of each first swing arm  28 . More specifically, each first feed roller  26  may be mounted, via a one-way clutch  90 , to a shaft  88  that is supported rotatably at an end of first swing arm  28 . Thus, each first feed roller  26  may be positioned on the upper surface of lower sheet tray  13  near an end in its width, e.g., lateral, direction. Each first feed roller  26  may be positioned between plate members  85 . A roller surface of first feed roller  26  may be covered with a rubber member to cause high friction when first feed roller  26  contacts a recording sheet. 
     Drive force transmission mechanism  31  may comprise transmission gears  87 ,  89  and four intermediate gears  84 . Transmission gear  87  may be fixed to drive shaft  29  inside plate member  85 . When drive shaft  29  rotates, transmission gear  87  may rotate in the same direction as drive shaft  29 . Transmission gear  89  may be fixed to shaft  88  inside plate member  85 . When shaft  88  rotates, transmission gear  89  may rotate in the same direction as shaft  88 . Four intermediate gears  84  may be positioned between transmission gears  87 ,  89 . As shown in  FIG. 6 , each intermediate gear  84  may be supported rotatably by a shaft  86  that may be positioned on plate member  85 . A gear train from transmission gear  87  to transmission gear  89  via intermediate gears  84  may be positioned along first swing arm  28 . Drive force input to drive shaft  29  may be transmitted to shaft  88  of first feed roller  26 , via transmission gear  87 , intermediate gears  84  and transmission gear  89 . 
     Drive force transmission mechanism  31  may be configured to transmit drive force to shaft  88  of first feed roller  26  from drive shaft  29  via six gears. Drive force in the direction opposite to the rotating direction of drive shaft  29  may be transmitted to shaft  88  of first feed roller  26 . In other words, shaft  88  may be rotated in the direction opposite to the rotating direction of drive shaft  29 . 
     Drive force transmission mechanism  31  may comprise one-way clutch  90 . One-way clutch  90  may be fitted into an inner hole of first feed roller  26 . One-way clutch  90  may be configured to transmit drive force to first feed roller  26  when the drive force to feed a recording sheet in the sheet feeding direction, e.g., in the direction of arrow  43 , is transmitted to shaft  88 . One-way clutch  90  also may be configured to slip, e.g., to not transmit drive force to first feed roller  26 , when the drive force to feed a recording sheet in a direction opposite to the sheet feeding direction is transmitted to shaft  88 . When drive shaft  29  is rotated in the clockwise direction in  FIG. 6 , drive force in the counterclockwise direction transmitted to each shaft  88  from drive shaft  29  via gears may be interrupted with one-way clutches  90 . Therefore, the drive force may not be transmitted to first feed rollers  26 . At this time, as drive shaft  29  is rotated in the clockwise direction, first swing arms  28  supported pivotably by drive shaft  29  may be urged in a direction away from the bottom plate of lower sheet tray  13 . Recording sheets in lower sheet tray  13  may be held in tray  13 . When drive shaft  29  is rotated in the counterclockwise direction in  FIG. 6 , drive force in the clockwise direction transmitted to each shaft  88  from drive shaft  29  via gears may be transmitted to first feed rollers  26  with one-way clutches  90 . At this time, as drive shaft  29  is rotated in the counterclockwise direction, first swing arms  28  supported rotatably by drive shaft  29  may be urged in a direction the bottom plate of lower sheet tray  13 . 
     Each first swing arm  28  may be urged in a direction approaching the bottom plate of lower sheet tray  13  by its own weight, weights of corresponding first feed roller  26  and drive force transmission mechanism  31  and force of a spring (not shown). When the roller surfaces of first feed rollers  26  are brought into contact with a recording sheet in lower sheet tray  13 , first swing arms  28  may stop. As drive force in the direction of feeding a recording sheet, e.g., the direction of arrow  43 , is transmitted to first feed rollers  26  with first swing arms  28  stopped, friction force may be generated between the roller surface of each first feed roller  26  and a recording sheet, and the recording sheet may be fed in the sheet feeding direction. In an embodiment, first feed roller  26  may be positioned at each end of lower sheet tray  13  in its width, e.g., lateral, direction, such that sufficient feeding force may be applied to a recording sheet in lower sheet tray  13 . 
     With sheet feeding mechanism  33  configured as described above, recording sheets held in upper sheet tray  12  or lower sheet tray  13  may be fed selectively with a drive control to switch a rotating direction of motor  71  in the clockwise or counterclockwise direction. In this embodiment, gears may be arranged in a direct path from drive shaft  29  to sheet trays  12 ,  13 , such that drive force transmission mechanisms  30 ,  31  may be reduced in size. Because gears are not positioned above drive shaft  29 , a recording device such as platen  48  and recording unit  24  may be positioned directly above drive shaft  29 . Thus, MFD  1  may be reduced in thickness. 
     While the invention has been described in connection with various exemplary structures and illustrative embodiments, it will be understood by those skilled in the art that other variations and modifications of the structures and embodiments described above may be made without departing from the scope of the invention. Other structures and embodiments will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and the described examples are illustrative with the true scope of the invention being defined by the following claims.