Abstract:
The invention is directed to a paper feed cassette device to be removably installed to image recording device. The paper feed cassette device includes a paper feed cassette portion and a paper discharge tray portion that receives the recording media. The paper feed cassette portion has a first paper feed cassette portion and a second paper feed cassette portion that selectively contracts and extends by sliding along a particular direction. The paper discharge tray portion has a first paper discharge tray portion disposed above the first paper feed cassette portion and a second paper discharge tray portion that selectively contracts and expands by sliding along the particular direction. The second paper discharge tray portion selectively engages the second paper feed cassette portion, and the second paper feed cassette portion and the second paper discharge tray portion integrally slide with respect to the first paper discharge tray portion.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to and the benefit of Japanese Patent Application No. 2008-021417, which was filed on Jan. 31, 2008, 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 a paper feed cassette device integrally including a paper discharge tray, and an image recording device wherein the paper feed cassette apparatus is removably installed. 
     2. Description of the Related Art 
     In a known image recording device, e.g., a copy device and a printer device, an arrangement is made to removably install a paper feed cassette device that accommodates recording media before being subjected to recording, in an accumulated state. Image recording devices have been increasingly frequently used not only in for business use, e.g., for companies and the like, but also in homes for small-scale offices or individuals. Many types and sizes of paper, e.g., B5 to A3, L size, postcard size, regal size, and the like, may be required to be used. 
     However, when attempting to prepare paper feed cassette devices for each paper size, many kinds of paper feed cassette devices are needed. Also, when attempting to allow many kinds of paper feed cassette devices to be concurrently mounted on an image recording device using a known image recording device, the device may grow large. Moreover, when attempting to use many kinds of paper feed cassette devices while exchanging with one another, space for storing preliminary paper feed cassette devices may be required. 
     In a known image recording device, e.g., a recording device described in Japanese Unexamined Patent Application Publication No. 2007-181933, two paper feed cassette devices are provided at upper and lower stages, and a slide tray in the upper-stage paper feed cassette device is configured to be extendable/contractible. In the known image recording device, the upper and lower stage paper feed cassette devices are designed to accommodate paper of sizes different from each other, and to be able to accommodate paper of further different sizes by extending and contracting of the upper-stage paper feed cassette device. 
     In another known image recording device, e.g., a recording device described in Japanese Unexamined Patent Application Publication No. 2000-247456, a paper feed cassette device has a cover of an upper-stage paper feed cassette device that also serves as a paper discharge tray portion, and when paper of a large size is discharged, the mounting area of the cover is enlarged by extending an subsidiary tray of the paper discharge tray portion. Nevertheless, although a subsidiary tray is locked to a main body portion of the paper feed cassette device, an extendable/contractible movable casing is not locked thereto. Therefore, the subsidiary tray of the paper discharge tray portion may be extended even though the paper feed cassette device has not been not extended. Since the paper discharge tray portion doubles as the cover of the paper feed cassette device and is formed comparatively thin, it is low in rigidity. 
     Also, there are other known image recording devices in which, when the paper feed cassette device is configured to be able to feed paper of a plurality of kinds of sizes, although the paper discharge tray portion is set to a size in conformance with paper of a small size, a command for making a record onto paper of a larger size is issued without noticing the above-described state. Such a situation is prone to occur in the case wherein, for example, there are provided a plurality of paper feed cassette devices, and paper of a large size is accommodated within the lower-stage paper feed cassette device while paper of a small size is accommodated within the upper-stage paper feed cassette device. 
     If the mounting area of the paper discharge tray portion is smaller than the area of discharged paper, the paper may drop off from the paper discharge tray portion, and the order of discharge may be lost, thereby requiring time and effort to re-sequence the discharged paper. Moreover, in an arrangement incapable of easily performing extension/contraction, it has been necessary to perform an operation for extending the paper discharge tray portion after having once interrupted the recording command. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to a paper feed cassette device and an image recording device for quickly performing extension/contraction of its paper discharge tray portion in accordance with the size of paper to be discharged, and for improving stability of the paper discharge tray portion, by configuring these devices so that paper of different sizes is configured to be fed thereto, and that the paper feed tray portion is extendable/contractible. 
     In an embodiment of the invention, a paper feed cassette device is configured to be removably installed in an image recording device, the paper feed cassette device comprising a paper feed cassette portion configured to accommodate recording media to be fed, the paper feed cassette portion comprising, a first paper feed cassette portion, and a second paper feed cassette portion configured to selectively contract and extend by sliding along a particular direction. The paper feed cassette device also comprising a paper discharge tray portion disposed above the paper feed cassette portion and configured to receive the recording media after the recording media is discharged. The paper discharge tray portion comprises a first paper discharge tray portion disposed above the first paper feed cassette portion, and a second paper discharge tray portion configured to selectively contract and expand by sliding along the particular direction, wherein the second paper discharge tray portion is configured to selectively engage the second paper feed cassette portion, and wherein the second paper feed cassette portion and the second paper discharge tray portion are configured to integrally slide with respect to the first paper discharge tray portion. 
     In another embodiment of the invention, an image recording device comprises a recording portion disposed inside a casing, and an accommodation portion configured to accommodate a paper feed cassette device. The paper feed device cassette comprises a paper feed cassette portion configured to accommodate recording media to be fed, and the paper feed cassette portion comprises a first paper feed cassette portion and a second paper feed cassette portion configured to selectively contract and extend by sliding along a particular direction. The paper feed cassette device also comprises a paper discharge tray portion disposed above the paper feed cassette portion and configured to receive the recording media at a mounting portion after the recording media is discharged, and the paper discharge tray portion comprises a first paper discharge tray portion disposed above the first paper feed cassette portion, and a second paper discharge tray portion configured to selectively contract and expand by sliding along the particular direction. The image recording device also comprises an opening portion disposed in one side surface of the casing, wherein the second paper discharge tray portion is configured to selectively engage the second paper feed cassette portion, and wherein the second paper feed cassette portion and the second paper discharge tray portion are configured to integrally slide with respect to the first paper discharge tray portion, and wherein the paper feed cassette device is configured to be selectively inserted into and withdrawn from the accommodation portion through the opening portion, and wherein the mounting portion of the paper discharge tray portion is configured to conform to a predetermined size of a recording medium when the second paper discharge tray portion is slid toward the outside of the paper feed device cassette. 
     In yet another embodiment of the invention, an image recording device comprises a recording portion disposed inside a casing, and an accommodation portion configured to accommodate a paper feed cassette device. The paper feed device cassette comprises a paper feed cassette portion configured to accommodate recording media to be fed, and the paper feed cassette portion comprises a first paper feed cassette portion and a second paper feed cassette portion configured to selectively contract and extend by sliding along a particular direction. The paper feed cassette device also comprises a paper discharge tray portion disposed above the paper feed cassette portion and configured to receive the recording media at a mounting portion after the recording media is discharged, and the paper discharge tray portion comprises a first paper discharge tray portion disposed above the first paper feed cassette portion, and a second paper discharge tray portion configured to selectively contract and expand by sliding along the particular direction. The image recording device also comprises an opening portion disposed in one side surface of the casing, wherein the second paper discharge tray portion is configured to selectively engage the second paper feed cassette portion, and wherein the second paper feed cassette portion and the second paper discharge tray portion are configured to integrally slide with respect to the first paper discharge tray portion, and wherein a lower-stage paper feed cassette device is configured to be selectively inserted into and withdrawn from the accommodation portion below the paper feed cassette device in the opening portion, and wherein the lower-stage paper feed cassette device is configured to accommodate a first size of a recording medium, and the paper feed cassette device is configured to accommodate a second size of a recording medium, and the first size is greater than or equal to the second size. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the invention, reference now is made to the following descriptions taken in connection with the accompanying drawings. 
         FIG. 1  is a schematic perspective view of a multifunction device according to an embodiment of the invention; 
         FIG. 2  is a sectional view taken away along the II-II line in  FIG. 1 ; 
         FIG. 3  is a schematic side sectional view of the multifunction device according to an embodiment of the invention; 
         FIG. 4  is an enlarged view of the area around an opening portion of the multifunction device; 
         FIG. 5A  is a perspective view of an upper-stage paper feed cassette device in its contracted state, according to an embodiment of the invention; 
         FIG. 5B  is a perspective view of the upper-stage paper feed cassette device in its extended state, according to an embodiment of the invention; 
         FIG. 6A  is a plan view of the upper-stage paper feed cassette device in its contracted state, according to an embodiment of the invention; 
         FIG. 6B  is a sectional view taken along the line VIa-VIb in  FIG. 6A ; 
         FIG. 7A  is a bottom plan view of a first paper feed cassette portion, according to an embodiment of the invention; 
         FIG. 7B  is a top plan view of a second paper feed cassette portion, according to an embodiment of the invention; and 
         FIG. 8  is a perspective view showing an operation portion of locking portion according to another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Exemplary embodiments of the present invention may be understood by referring to  FIGS. 1-8 , like numerals being used for like corresponding parts in the various drawings. 
       FIGS. 1 to 7  show a printer and paper feed cassette device according to an embodiment of the invention. In an embodiment, an image recording device, a multifunction device (“MFD”)  1  may have a printer function, a scanner function, a copy function, and a facsimile function. The image recording device also may be a discrete device having a single function, e.g., a scanner device, a copy device, a facsimile device, and the like. 
       FIG. 1  shows a schematic perspective view of the multifunction device according to an embodiment. In the multifunction device  1 , an upper part of a body case, e.g., a housing  2  may comprise a synthetic resin. A scanner portion, e.g., an image reading device  3 , for original document reading, e.g., by the copy function or the facsimile function, may be disposed on the upper part of the body case. The image reading device  3  may read an original document and may create image data, e.g., picture data, document data, or both. 
     Using its copy function, the multifunction device  1  may record the data created by the image reading device  3  on a recording medium, e.g., paper, as an image, e.g., a picture, a document, and the like. Multifunction device  1  also may use its facsimile function to transmit the image data created by the image reading device  3  via a network, e.g., a telephone communication network. Furthermore, the multifunction device  1  may transmit the image data created by the image reading device  3  to a personal computer connected thereto via a cable or the like. 
     In an embodiment, the image reading device  3  may be a flatbed scanner. Referring to  FIG. 3 , the multifunction device  1  may comprise an original document reading glass  5  and image sensor  6 , provided below an original document cover  4  serving as a top plate, which may be opened and closed. Referring again to  FIG. 1 , in an embodiment of the invention, image sensor  6  may comprise a contact image sensor (“CIS”) that may extend further in a direction represented by the X-axis direction of  FIG. 1  than in a direction represented by the Y-axis direction of  FIG. 1 . In another embodiment of the invention, image sensor  6  may comprise a charge coupled device (“CCD”). An original document to be subjected to image reading may be placed on the original document reading glass  5 , and the image sensor  6  may perform image reading by reciprocating along the Y-axis direction of  FIG. 1 , below the original document reading glass  5 . 
     The original document cover  4  may comprise an automatic original document conveying mechanism, e.g., auto document feeder (“ADF”)  7 . The ADF  7  may convey original documents placed on an original document tray  8 , which is shown in its closed state in  FIG. 1 . Original documents may be fed, one after another, onto the original document reading glass  5 , and image sensor  6  may remain stationary below the original document reading glass  5 , while reading original documents fed onto the original document reading glass  5 . The original documents that have been read may be discharged to an original document discharge tray  9 . 
     Multifunction device  1  may comprise a control panel  10  disposed in an upper portion in the front multifunction device  1 . Control panel  10  may be equipped with control buttons or a liquid crystal display portion which may be operated to command various operations. A slot portion  11  may be disposed below the control panel  10 , and may be loadable with various compact memory cards serving as recording media. 
       FIGS. 2 and 3  show the internal structure of the multifunction device  1  according to an embodiment of the invention. As shown, a recording portion  12  may be arranged in a central portion of the body case  2 . The recording portion  12  may comprise inkjet-type recording heads  13 . An ink cartridge (not shown), which may be accommodated inside the body case  2 , may supply color inks to recording heads  13 , Flexible ink supply tubes may deliver different color inks independently of each other. 
     As shown in  FIGS. 1 and 4 , a lower portion in the front of the multifunction device  1 , may have an opening portion  14 , and a paper feed cassette device, e.g., upper-stage paper feed cassette device  20 , and a lower-stage paper feed cassette device  30 , each may be arranged in the opening portion  14 . Upper-stage paper feed cassette device  20 , and a lower-stage paper feed cassette device  30  each may be arranged to be removably inserted substantially along a horizontal direction, with respect to an accommodation portion  16 , disposed in the bottom of the body case  2 , through the opening portion  14 . Hereinafter, the side in which the opening portion  14  in the body case  2  is located is referred to as the front, or the front side. The back side, opposite the front side, and the right and left of the device also may be defined using the above-described front as a reference. Also, as described above, the back-to-front direction of the multifunction device  1  is aligned along the X-axis direction, and the right-to-left direction thereof is aligned along the Y-axis direction. 
     As shown in  FIG. 4 , rail-shaped guide portions may be disposed on right and left inner side surfaces of the opening portion  14 , for inserting the upper-stage and lower-stage paper feed cassette devices  20  and  30  into respective positions. The guide portions  15  each may be disposed at a position which may abut against the top surface of a paper discharge tray portion  40 , which will be described in more detail herein. 
     The upper-stage and lower-stage paper feed cassette devices  20  and  30  each may be configured to accumulate and accommodate a large number of recording media, e.g., paper sheets. The upper-stage and lower-stage paper feed cassette devices  20  and  30  each may be removably inserted into and withdrawn from the multifunction device  1 , in the substantially same direction as a feed direction of the accommodated paper sheets. The depth side of the upper-stage and lower-stage paper feed cassette devices  20  and  30  in the insertion and withdrawal direction may constitute a downstream side of the feed direction of the paper sheets. 
     An upper-stage separation tilt plate  21  may be disposed on the depth side of the upper-stage paper feed cassette device  20 , e.g., the right side as shown in  FIGS. 2 and 3 . Also, an upper-stage paper feed roller  23  may be pivotally supported on a front end of an upper-stage paper feed arm  22 , and may be disposed at a position opposite to a position on the depth side of the bottom surface of the upper-stage paper feed cassette device  20 . The upper-stage paper feed arm  22  may be urged resiliently in the downward direction, and the upper-stage paper feed roller  23  may abut against the uppermost top surface of paper sheets that may be accumulated and accommodated within the upper-stage paper feed cassette device  20 . A driving source (not shown) may transmit a driving force to the upper-stage paper feed roller  23  to rotate it, and upper-stage paper feed roller  23  may separate one sheet of the paper P after another at the uppermost layer, by a cooperative operation between the upper-stage paper feed roller  23  and the upper-stage separation tilt plate  21 . After separation, the paper P may be guided in an upward direction. 
     The upper-stage paper conveying path  24  may be formed into a U-turn shape that curves toward the front side of the multifunction device  1 , after having moved in an upward direction away from the upper-stage separation tilt plate  21 . The paper P may be discharged to the paper discharge tray portion  40  after the recording portion  12  records the image on the paper P. The upper-stage paper feed arm  22  may perform an ascending and a descending operation following an inserting and a withdrawing operation, respectively, of the upper-stage paper feed cassette device  20 , which may allow upper-stage paper feed roller  23  to avoid colliding against the upper-stage separation tilt plate  21 . 
     The lower-stage paper feed cassette device  30  also is formed substantially in the same manner as the upper-stage paper feed cassette device  20 . A lower-stage separation tilt plate  31  may be disposed on the depth side, e.g., the right side as shown in  FIGS. 2 and 3  of the lower-stage paper feed cassette device  30 . Also, a lower-stage paper feed roller  33  may be pivotally supported on a front end of a lower-stage paper feed arm  32 , and may be disposed at a position opposite to a position on the depth side of the bottom surface of the lower-stage paper feed cassette device  30 . The lower-stage paper feed arm  32  may be urged resiliently in the downward direction, and the lower-stage paper feed roller  33  may abut against the uppermost top surface of paper sheets that may be accumulated and accommodated within the lower-stage paper feed cassette device  30 . A driving source (not shown) may transmit a driving force to the lower-stage paper feed roller  33  to rotate it, and lower-stage paper feed roller  33  may separate one sheet of the paper P after another at the uppermost layer, by a cooperative operation between the lower-stage paper feed roller  33  and the lower-stage separation tilt plate  31 . After separation, the paper P may be guided in an upward direction. 
     The lower-stage paper conveying path  34  may be disposed further toward an outer wall of casing  2  than the upper-stage paper conveying path  24 , and may be formed into a U-turn shape, e.g., an arcuate shape, which may be larger than the shape formed by the upper-stage paper conveying path  24 . The U-turn shape of lower-stage paper conveying path  34  may curve to the front side of the multifunction device  1  after having moved in an upward direction from the lower-stage separation tilt plate  31 . Recording portion  12  may record an image on the paper that has been conveyed via the lower-stage paper conveying path  34 , the paper with the recorded image then may be discharged to the paper discharge tray portion  40 . The lower-stage paper feed arm  32  may perform an ascending and a descending operation following an inserting and a withdrawing operation, respectively, of the upper-stage paper feed cassette device  20 , which may allow lower-stage paper feed roller  33  to avoid colliding against the lower-stage separation tilt plate  31 . 
     The upper-stage paper feed cassette device  20  may be disposed at a position at which the above-described paper discharge tray portion  40  may overlap a portion of the paper feed cassette portion, e.g., the upper-stage paper feed cassette portion  25 . Paper sheets fed from the upper-stage paper feed cassette device  20  and paper sheets fed from the lower-stage paper feed cassette device  30  may be discharged to the paper discharge tray portion  40 . The paper sheets may be accumulated in paper discharge tray portion  40  in the order of discharging. 
     The upper-stage paper feed cassette portion  25  in the upper-stage paper feed cassette device  20  may have a substantially boxy shape, of which the top surface may be substantially opened. The paper discharge tray portion  40  also may act as a substantially dustproof cover for paper accommodated within the upper-stage paper feed cassette portion  25 , and may have a substantially thin planar shape. Therefore, the paper discharge tray portion  40  may be configured to cover, in a lid shape, at least a portion of an upper opening of the upper-stage paper feed cassette portion  25 , except for a portion which may interfere with the upper end paper feed arm  22 , e.g., at least a portion near the opening portion  14 . 
     As shown in  FIG. 3 , the upper-stage paper feed cassette portion  25  may comprise a first paper feed cassette portion  26  located on its depth side, e.g., the right side as shown in  FIGS. 2 and 3 , in the insertion and withdrawal direction, e.g., in the X-axis direction, and a second paper feed cassette portion  27  that may be installed such that second paper feed cassette portion may be extendable and contractible by sliding along the insertion and withdrawal direction with respect to the first paper feed cassette portion  26 . Specifically, as shown in  FIG. 3 , the second paper feed cassette portion  27  may be installed at a position at which its paper mounting plate  27   a  overlaps below at least a portion of a paper mounting plate  26   a  of the first paper feed cassette portion  26 . A grip portion  25   a  may be disposed on a side surface on the front side, e.g., the front surface of the second paper feed cassette portion  27 . 
     As described in more detail herein, the second paper feed cassette portion  27  may be configured to be installed such that the second paper feed cassette portion may be configured to be held at a plurality of, e.g., three, stages, e.g., three states, e.g., three locking states. The three stages, e.g., states may correspond to: 1) a position where second paper feed cassette portion  27  may be contracted with respect to the first paper feed cassette portion  26 ; 2) a position where second paper feed cassette portion  27  may be extended with respect to the first paper feed cassette portion  26 ; and 3) an intermediate position between the first and the second positions. When the second paper feed cassette portion  27  is slid to a position at which second paper feed cassette portion  27  is fully extended in the X-axis direction, the paper of A3 size may be accommodated, e.g., configured such that that the longitudinal direction of the paper of A3 size may be accommodated along the X-axis direction. When the second paper feed cassette portion  27  is slid to a position at which second paper feed cassette portion  27  is fully contracted, the paper of A4 size may be accommodated, e.g., configured such that the longitudinal direction of the paper of A4 size may be accommodated along the Y-axis direction. 
     The upper-stage paper feed cassette portion  25  may comprise a pair of side guides  28 , which may be configured to guide side edges along the X-axis direction of the paper, and upper-stage paper feed cassette portion discretionarily may perform a width adjustment of the distance between the side guides  28  in the Y-axis direction by the known operative association mechanism. By adjusting the distance between the side guides  28 , the paper to be accommodated may be subjected to a centering operation with respect to the upper-stage paper feed cassette portion  25 . The adjustment by the side guides  28  and the adjustment by the extension or contraction of the second paper feed cassette portion  27  may allow paper from the L size up to the A3 size to be accommodated within the upper-stage paper feed cassette portion  25 . 
     Regarding lower-stage paper feed cassette device  30 , the lower-stage paper feed cassette portion  35  also may be configured to serve as a paper accommodation portion, and may comprise a lower-stage first paper feed cassette portion  36  disposed on its depth side, e.g., the right side as shown in  FIGS. 2 and 3 , in the insertion and withdrawal direction, e.g., in the X-axis direction, and a lower-stage second paper feed cassette portion  37  that may be installed such that second paper feed cassette portion may be extendable and contractible by sliding along the insertion and withdrawal direction with respect to the lower-stage first paper feed cassette portion  36 . 
     The lower-stage second paper feed cassette portion  37  may be installed such that lower-stage second paper feed cassette portion  37  may move between two stages. The first stage may correspond to a position at which lower-stage second paper feed cassette portion  37  may be contracted with respect to the lower-stage first paper feed cassette portion  36 , and the second stage may correspond to a position at which lower-stage second paper feed cassette portion  37  position may be extended with respect to the lower-stage first paper feed cassette portion  36 . 
     In an embodiment, lower-stage paper feed cassette portion  35  may comprise side guides  38 , shown in more detail in  FIG. 2 . As in the case of the upper-stage paper feed cassette portion  25 , the lower-stage paper feed cassette portion  35  also discretionarily may perform a width adjustment of the distance between the side guides  38  in the Y-axis direction, which may cause the paper to be accommodated to be the subject of a centering operation with respect to the lower-stage paper feed cassette portion  35 . A grip portion  35   a  may be disposed on a side surface on the front side, e.g., the front surface, of the second paper feed cassette portion  27 . 
     The paper discharge tray portion  40  may comprise a first paper discharge tray portion  41  which may overlap a portion of the first paper feed cassette portion  26  in the upper-stage paper feed cassette device  20 , and a second paper discharge tray portion  42  which may be installed such that the second paper discharge tray portion  42  may be extendable and contractible by being slid along the insertion and withdrawal direction, respectively, with respect to the first paper feed cassette portion  41 . As shown in  FIGS. 5A and 5B , the paper discharge tray portion  40  may be installed such that the first paper discharge tray portion  41  may overlap below at least a portion of the second paper discharge tray portion  42 . A grip portion  45  may be disposed at a position on the front side of the second paper discharge tray portion  42 . A pair of ribs  46  may be disposed on the top surface of the second paper discharge tray portion  42 . Ribs  46  may be arranged on the right and left sides of the top surface of the second paper discharge tray portion  42 , and ribs  46  may protrude and extend along the X-axis direction. Ribs  46  may prevent, resist, or inhibit the paper from dropping off by inclining upward the end on the front side of the paper to be mounted. 
     The paper discharge tray portion  40  may be configured to pivotally support the upper-stage paper feed cassette portion  25  by a hinge portion  43  disposed on the depth side of the paper discharge tray portion  40 . The front side, e.g., the side near the opening portion  14 , the paper discharge tray portion  40 , may turn upward about the depth side, e.g., the far side of the opening portion  14 . This configuration may allow a user to perform an operation for setting the paper within the upper-stage paper feed cassette portion  25  by grasping the grip portion  45  of the paper discharge tray portion  40  and lifting up the paper discharge tray portion  40 . As described in more detail herein, the turning of the paper discharge tray portion  40  may be operated in a state wherein the upper-stage paper feed cassette device  20  has been removed from the multifunction device  1 . 
     As shown in  FIGS. 6A and 6B , engagement recesses  44  may be formed at both the right and left ends on the front side of the second paper discharge tray portion  42  in the paper discharge tray portion  40 . Engagement recesses  44  may open downward. Moreover, boss portions  29  may be formed at both the right and left ends on the front side of the second paper feed cassette portion  27  in the upper-stage paper feed cassette portion  25 . Boss portions  29  may as protrude upward in order to provide concave-convex fitting with the engagement recesses  44 . When the boss portions  29  and the engagement recesses  44  are concavo-convex interlocked, the second paper discharge tray portion  42  and the second paper feed cassette portion  27  may be integrally extended and contracted. That is, the sliding of the second paper discharge tray portion  42  and that of the second paper feed cassette portion  27  may be integrally performed in operative association with each other. 
     Referring to  FIG. 4 , the guide portions  15  provided in the opening portion  14  of the multifunction device  1  may abut against both ends on the right and left on the top surface of the second paper discharge tray portion  42  in the paper discharge tray portion  40 . Therefore, when the second paper discharge tray portion  42  and the second paper feed cassette portion  27  are in a first state wherein they have slid and extended in an integral manner, wobbling thereof in a vertical direction may be inhibited, resisted, or constrained by the guide portions  15 . Also, in a state of having been inserted into the opening portion  14 , the upper-stage paper feed cassette device  20  may not open the second paper discharge tray portion  42  about the hinge portion  43 , and hence, when setting the paper; setting operation may be performed with the opening portion  14  withdrawn from the opening portion  14 . 
     The upper-stage paper feed cassette portion  25  may comprise locking portion  50  which may be configured to hold an extension and contraction position of the second paper feed cassette portion  27 , with respect to the first paper feed cassette portion  26 , or for allowing sliding of the second paper feed cassette portion  27 . As shown in  FIGS. 7A and 7B , locking portion  50  may be disposed to hold the position of the second paper feed cassette portion  27 , which may prevent the second paper feed cassette portion  27  from being inadvertently extended/contracted. 
     Locking portion  50  may comprise a locking bar  51  extending in the X-direction. Locking bar  51  may be disposed at a position near one side surface  27   b , e.g., the right side as shown in  FIG. 1 , of the second paper feed cassette portion  27 , on the top surface of the paper mounting plate  27   a  in the second paper feed cassette portion  27 . The locking bar  51  is pivotally supported on the paper mounting plate  27   a , and is disposed to protrude at a position near the front surface  27   c  of the second paper feed cassette portion  27 , e.g., a position on the front side thereof in the insertion and withdrawal direction, such that the locking bar  51  may swing in the horizontal direction about a rotational shaft  56 . 
     In an embodiment of the invention, an operation portion  52  of the locking bar  51  may be formed, and may be bent into an L-shape, and may extend from the position of the rotational shaft  56  in the Y-axis direction, along the front surface  27   c . The front end on the depth side of the locking bar  51  may be bent into an L-shape with respect to a center line of the paper mounting plate  27   a , and may comprise a protruding portion  53  which may be configured to engage the first paper feed cassette portion  26 . 
     A guide rail  60  extending in the X-axis direction may be installed integrally with locking bar  51 , on the bottom surface side of the paper mounting plate  26   a  of the first paper feed cassette portion  26 . Engagement receiving portions, which are configured to selectively engage with the protruding portion  53 , may be formed at three places in the guide rail  60 , shown in  FIG. 7A  as engagement receiving portions  61   a  to  61   c , along the X-axis direction. The engagement receiving portions  61   a  to  61   c  each may be formed into a concave shape that may open in a sideward direction, such that the protruding portion  53  may be locked to one of the engagement receiving portions thereto. 
     In an embodiment of the invention, in a first state, the protruding portion  53  of the locking bar  51  may be locked to the engagement receiving portion  61   a . In this state, second paper feed cassette portion  27  may be in a fully contracted state with respect to the first paper feed cassette portion  26 . In this state, the upper-stage paper feed cassette portion  25  may be configured for use in mounting the paper of A4 size thereon, with its longitudinal direction along the Y-axis direction, or for use in mounting the paper of a size smaller than the A4 size thereon. 
     In an embodiment of the invention, in a second state, the protruding portion  53  of the locking bar  51  may be locked to the engagement receiving portion  61   c . In this state, second paper feed cassette portion  27  may be in a fully extended state with respect to the first paper feed cassette portion  26 . In this state, the upper-stage paper feed cassette portion  25  may be configured for use in mounting the paper of A3 size thereon, with its longitudinal direction being along the X-axis direction. 
     In an embodiment of the invention, in a third state, the protruding portion  53  of the locking bar  51  may be locked to the engagement receiving portion  61   b . In this state, the second paper feed cassette portion  27  may be extended to a substantially midway position. In this state, the upper-stage paper feed cassette portion  25  is suitable for use in mounting thereon the paper of A4 size, with its longitudinal direction being along the X-axis direction. 
     Moreover, in an embodiment of the invention, in an unlocked state, the protruding portion  53  of the locking bar  51  may be locked to none of the engagement receiving portions  61   a  to  61   c . In this state, the second paper feed cassette portion  27  may slide. Inclined surfaces that incline in right and left directions in a plan view may be disposed between the engagement receiving portions in the guide rail  60 . These inclined surfaces may be configured to provide smoothly performing engagements and disengagements between locking bar  51  and engagement receiving portions  61   a  to  61   c.    
     In an embodiment, the extension and contraction position of the second paper feed cassette portion  27  with respect to the first paper feed cassette portion  26  may be configured to be changeable among three stages. Nevertheless, the extension and contraction positions are not limited to three stages. For example, in another embodiment, the extension and contraction position may be changed between two stages, . . . , a first stage in which the second paper feed cassette portion  27  may be fully extended, and second stage in which the second paper feed cassette portion  27  may be fully contracted. Alternatively, the extension and contraction positions may be changed in more than three stages. 
     As shown in  FIG. 6A , in the second paper discharge tray portion  42 , a penetrating portion  55  may have an opening area large enough to allow the insertion of a finger of the user formed therethrough. The opening area may be disposed on the right side on the front side of the plate surface, and may expose the operation portion  52  of the locking bar  51  to the outside. Here, the penetrating portion  55  and the operation portion  52  may be disposed toward the right side of the multifunction device  1 . This configuration may be more convenient for a right-handed user. 
     In an embodiment, when the user inserts his/her finger into the penetrating portion  55 , the user may touch the operation portion  52  of the locking bar  51  disposed below the penetrating portion  55 . When the user pulls the operation portion  52  toward the user&#39;s side by the finger that has been inserted into the operation portion  52 , the locking bar  51  may swing in the horizontal direction, about the rotational shaft  56 , e.g., in a clockwise direction when viewed in a plan view, thereby allowing the protruding portion  53  to disengage from one of the engagement receiving portions, . . . , engagement receiving portions  61   a ,  61   b , or  61   c.    
     In the first state, e.g., the state in which the protruding portion  53  of the locking bar  51  may be locked to the engagement receiving portion  61   a , the user may insert an index finger into the penetrating portion  55  and may pull the operation portion  52  toward the user&#39;s side, with the thumb placed on the front surface side of the second paper feed cassette portion  27 , or the second paper discharge tray portion  42 . The user then may pull the second paper discharge tray portion  42  toward the user&#39;s side, e.g., outside of the opening portion  14 . Thereupon, due to the concave-convex fitting between the engagement recesses  44  and the boss portions  29 , the second paper feed cassette portion  27  and the second paper discharge tray portion  42  integrally may operate, may be pulled out toward the front side in the withdrawal direction. Then, the user freely may move the second paper feed cassette portion  27  in a back-and-forth direction in an unlocked state, and may lock it in the second state, e.g., engagement receiving portion  61   c , or in the third state, e.g., engagement receiving portion  61   b.    
     Similarly, to execute sliding operations of the second paper feed cassette portion  27  and the second paper discharge tray portion  42 , the user may grasp their respective grip portions  25   a  and  45  to operate the respective portions. The penetrating portion  55  may be disposed on the front side of the second paper discharge tray portion  42 , which may allow the user to ascertain a remaining amount of the paper accommodated within the upper-stage paper feed cassette device  20 , via the penetrating portion  55 . 
     In an embodiment, paper of A3 size may be accommodated within the lower-stage paper feed cassette device  30 , and paper of A4 size may be accommodated with its longitudinal direction being along the X-axis direction. That is, the upper-stage paper feed cassette device  20  may be in the first state wherein the protruding portion  53  of the locking bar  51  may be engaged with the engagement receiving portion  61   a  of the guide rail  60 . In the upper-stage paper feed cassette device  20 , the second paper feed cassette portion  27  may be fully contracted with respect to the first paper feed cassette portion  26 , and the second paper discharge tray portion  42  also may be fully contracted with respect to the first paper discharge tray portion  41 . When the paper having A4 size is fed, to perform recording upon specifying the upper-stage paper feed cassette device  20 , even if the paper is discharged upon the paper discharge tray portion  40 , the paper may be mounted within the paper discharge tray portion  40  without the paper dropping off therefrom. 
     Nevertheless, the paper of A3 size may be fed to perform recording upon specifying the upper-stage paper feed cassette device  20 , e.g., if a user has forgotten that the paper discharge tray portion  40  has not been extended to a size corresponding to the A3 size. In such a case, as described above, in an embodiment, the insertion of a finger of the user into the penetrating portion  55  may allow the user to touch the operation portion  52  of the locking portion  50 . Therefore, the user may pull out the second paper discharge tray portion  42  integrally with the second paper feed cassette portion  27  while pulling the operation portion  52  toward the user&#39;s side. This operation may enlarge the mounting area of the second paper discharge tray portion  42 , which thereby may allow prevention of the discharged paper from dropping off. 
     The second paper discharge tray portion  42  may extend integrally with the second paper feed cassette portion  27 , and may be prohibited from singly extending. This may provide rigidity of the second paper discharge tray portion  42 , and may enable the discharged paper to be stably mounted thereon. 
     The paper discharge tray portion  40  also may be configured to serve as a lid for protecting the paper accommodated within the upper-stage paper feed cassette portion  25  against dust. As a consequence, if the operation portion  52  is covered in a scaled manner, with the paper discharge tray portion  40  not equipped with the penetrating portion, the user may be prevented from touching the operation portion  52 , even if the operation portion  52  of the locking portion  50  is disposed within the upper-stage paper feed cassette portion  25 . In order for a user to touch operation portion  52 , the user may extract the entire upper-stage paper feed cassette device  20  from the multifunction device  1  to open the paper discharge tray portion  40 . However, as in the above-described embodiment, disposing the penetrating portion  55  for exposing the operation portion  52  in the second paper discharge tray portion  42  may enable operation of the locking portion  50  even with the upper-stage paper feed cassette device  20  inserted in the multifunction device  1 . As a result, as described above, the paper discharge tray portion  40  quickly may be extended or contracted after a recording operation has been started. 
       FIG. 8  shows another embodiment of an operation portion. In this embodiment, an arrangement may be configured such that the user may touch an operation portion  152  of the locking portion  50  while bypassing the intermediary of the penetrating portion. In this embodiment, operation portion  152  may penetrate a side plate on the front side of the second paper feed cassette portion  27 , and operation portion  152  may be installed on the outer surface, e.g., the front surface. In this embodiment, the user should be careful not to inadvertently contact the locking portion  50 , thereby unlocking it. Nevertheless, in the arrangement disclosed in this embodiment, the user may more easily operate the operation portion  152  of the locking portion  50 . In this embodiment, at a position near the operation portion  152  of the second paper discharge tray portion  42 , a penetrating portion  155  may be disposed for the purposes of a user placing finger thereon and thereby ascertaining the remaining amount of the paper. The penetrating portion  155  may have a size sufficient for a user to insert a finger into the penetrating portion. The penetrating portion  155  may be formed by perforating a wall of the second paper feed cassette portion  27 . 
     For example, when the user puts an index finger on a penetrating portion  155  while pushing the operation portion  152  with a thumb, it may be possible to integrally slide the second paper discharge tray portion  42  and the second paper feed cassette portion  27  while releasing the locking portion  50 . Instead of the penetrating portion  155 , a concave-shaped grip portion, which may be configured to receive a user&#39;s finger thereon, may be installed. In this case, the dust resistance of the upper-stage paper feed cassette portion  25  may be enhanced. 
     In an embodiment of the invention, the upper-stage and lower-stage paper feed cassette devices  20  and  30  may be removably inserted into and withdrawn from the opening portion  14  of the multifunction device  1 . Nevertheless, another embodiment of the invention may be arranged such that a paper feed cassette device having a similar configuration to the upper-stage paper feed cassette device  20  may be removably inserted into and withdrawn from the opening portion  14 , and a paper feed cassette device having a similar configuration to the lower-stage paper feed cassette device  30  may not be removably inserted into and withdrawn from the opening portion  14 . In this embodiment, the mounting area when the paper discharge tray portion  40  has been extended may be configured to conform to a maximum size of paper which may be accommodated within the paper feed cassette device. As described above, when the second paper feed cassette portion  27  of the paper feed cassette device, e.g., the upper-stage paper feed cassette device  20 , is extended for accommodation of the paper of a large size, the second paper discharge tray portion  42  also may extend integrally therewith, which may prevent the user from forgetting to enlarge the mounting area of the paper discharge tray portion  40 . 
     While the invention has been described in connection with preferred embodiments, it will be understood by those of ordinary skill in the art that other variations and modifications of the preferred embodiments described above may be made without departing from the scope of the invention. Other 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 only are considered as exemplary of the invention, with the true scope of the invention being defined by the following claims.