Abstract:
A waiting tray is provided at some midpoint of a conveying path, and a sheet is caused to be in a waiting state when a post-process is required. Before performing the post-process, a processing tray receives the sheet conveyed from the waiting tray and the sheet conveyed from a conveying path without passing through the waiting tray. At this point, waiting tray parts are moved toward a direction in which the waiting tray parts are separated from each other, and a bundle of paper starts fall-down. When the bundle of paper falls down, the waiting tray parts are moved toward the direction in which the waiting tray parts are brought close to each other, and an alignment member performs alignment in a transverse direction of the bundle of paper.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2004-281771, filed Sep. 28, 2004, the entire contents of which are incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a sheet post-process apparatus, such as a finisher, which is designed for installation at the outlet side of a multi-function peripheral (MFP).  
         [0004]     2. Description of the Related Art  
         [0005]     An apparatus called “finisher” is known, which receives printed sheets supplied from an MFP and staples them together. In the finisher, the sheets supplied from the MFP are sequentially conveyed to a tray and stapled by a stapler, forming a bundle of sheets. The bundle of sheets is ejected from the apparatus onto a storage tray.  
         [0006]     Because the process of binding the sheets with stapler exists in a post-process in the finisher, a second tray previously temporarily accommodates a bundle of sheets, and then the bundle of sheets is caused to fall down on a first tray to staple the bundle of sheets with a stapler. The finisher, in which an alignment plate is provided in the first tray to perform transverse alignment of the second tray, is well known (Jpn. Pat. Appln. KOKAI Publication No. 2001-89009).  
         [0007]     However, in the finisher described in Jpn. Pat. Appln. KOKAI Publication No. 2001-89009, because mechanical parts are large in number, the apparatus can not sufficiently be miniaturized.  
       BRIEF SUMMARY OF THE INVENTION  
       [0008]     An object of the invention is to provide a sheet post-process apparatus which performs the alignment in a transverse direction of the sheet without difficulty.  
         [0009]     According to an aspect of the invention, there is provided a sheet post-process apparatus comprising: a plurality of rollers configured to receive and convey a sheet conveyed from an MFP main body; a waiting tray which is provided at some midpoint of a conveying path, and is configured to cause the sheet conveyed from the roller to be in a waiting state when a post-process is required, the waiting tray being freely opened and closed in a transverse direction orthogonal to a sheet conveying direction, an alignment member being vertically provided on a lower side surface of a loading surface on which the sheet is loaded; an open and close mechanism configured to open and close the waiting tray in a transverse direction; a processing tray configured to receive the sheet conveyed from the waiting tray and the sheet conveyed from a conveying path without passing through the waiting tray before performing the post-process; an alignment mechanism configured to align the sheets on the processing tray to form a bundle of sheets; a post-process mechanism configured to perform the post-process of the bundle of sheets aligned on the processing tray; a sheet conveying unit configured to convey the bundle of sheets to which the post-process has been performed from the processing tray; and a storage tray configured to load the conveyed bundle of sheets thereon.  
         [0010]     Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0011]     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.  
         [0012]      FIG. 1  is a perspective view of a post-process apparatus according to this invention;  
         [0013]      FIG. 2  is a top view of the post-process apparatus according to the invention;  
         [0014]      FIG. 3  is a perspective view illustrating how the waiting tray of the post-process apparatus performs its function;  
         [0015]      FIG. 4  is a perspective view depicting the sheet-bundle conveying mechanism provided in the post-process apparatus, and explaining how sheets are aligned at longitudinal edges in the post-process apparatus;  
         [0016]      FIG. 5  is a perspective view showing the mechanism for aligning sheets at their transverse edges;  
         [0017]      FIG. 6  is a perspective view illustrating how the stapler provided in the post-process apparatus performs its function;  
         [0018]      FIG. 7  is a sectional view of the post-process apparatus, showing how the first sheet moves from the input rollers to the sheet-feeding roller;  
         [0019]      FIG. 8  is a sectional view of the apparatus, explaining how the first sheet moves from the sheet-feeding rollers to the waiting tray;  
         [0020]      FIG. 9  is a sectional view of the apparatus, explaining how the second sheet moves from the sheet-feeding rollers to the waiting tray;  
         [0021]      FIG. 10  is a sectional view of the post-process apparatus, showing how the waiting-tray rollers operate;  
         [0022]      FIG. 11  is another sectional view of the apparatus, illustrating how the waiting-tray rollers operate;  
         [0023]      FIG. 12  is a sectional view of the apparatus, explaining how an active drop is carried out;  
         [0024]      FIG. 13  is a sectional view of the apparatus, explaining how the third sheet is conveyed;  
         [0025]      FIG. 14  is a sectional view of the apparatus, illustrating how the stapler operates;  
         [0026]      FIG. 15  is a sectional view of the apparatus, explaining how a bundle of sheets moves between the processing tray and the storage tray;  
         [0027]      FIG. 16  is a sectional view of the apparatus, illustrating how sheets move from the waiting tray to the storage tray;  
         [0028]      FIG. 17  is a sectional view of the apparatus, explaining how the position of the storage tray is changed;  
         [0029]      FIG. 18  is a view showing a cross section of the waiting tray and a drive mechanism in the post-process apparatus; and  
         [0030]      FIGS. 19A  to  19 D are a view which explain aligning sheets at their transverse edges by the waiting tray in the post-process apparatus respectively. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0031]     An embodiment of this invention will be described, with reference to the accompanying drawings.  
         [0032]      FIG. 1  is a perspective view of a sheet post-process apparatus according to this invention.  FIG. 2  is a top view of the post-process apparatus. As  FIG. 1  shows, the post-process apparatus comprises a waiting tray  10 , a processing tray  12 , a stapler  14 , a first storage tray  16 , and a second storage tray  18 .  
         [0033]     The sheet post-process apparatus further comprises a pair of input rollers  22 , a pair of sheet-feeding rollers  24 , and an input-roller motor  26 . The input rollers  22  receive a sheet  20  supplied from an MFP  1  (see  FIG. 7 ) and convey the sheet  20  to the sheet-feeding rollers  24 . The sheet-feeding rollers  24  convey the sheet  20  to the waiting tray  10 . The input-roller motor  26  drives the input rollers  22 .  
         [0034]     One of the input rollers  22  is an upper input roller  22 a, and the other input roller  22  is a lower input roller  22 b. Likewise, one of the sheet-feeding rollers  24  is an upper sheet-feeding roller, and the other sheet-feeding roller  24  is a lower sheet-feeding roller.  
         [0035]     The waiting tray  10  comprises two tray parts  10   a  and  10   b . The tray parts  10   a  and  10   b  can move from left to right, and vice verse. While an interval between the tray parts  10   a  and  10   b  is narrowed, the waiting tray  10  can receive sheets. Waiting-tray rollers  28 , a waiting-roller drive  30  and a waiting-roller motor  32  are provided. The waiting-tray rollers  28  align sheets on the tray parts  10   a  and  10   b  while both tray parts remain in the narrowed position. The waiting-tray rollers  28  can move up and down when they are driven and controlled by the waiting-roller drive  30 . The waiting-roller motor  32  rotates the waiting-tray rollers  28 .  
         [0036]     When the number of sheets  20  stacked on the waiting tray  10  reaches a prescribed value, a waiting-tray motor  34  drives the waiting-tray parts  10   a  and  10   b  to an opened position as is illustrated in  FIG. 3 . The sheets  20  fall onto the processing tray  12 , due to gravity. This event is known as “active drop”.  
         [0037]     Widths in the paper  20  conveying directions of the waiting tray  10  and the processing tray  12  are smaller than the width in the conveying direction of the paper  20 . When the paper falls down on the processing tray  12 , the paper  20  is loaded across the processing tray  12  and the first storage tray  16  (shown in  FIG. 2 ).  
         [0038]     Thus, the width along the conveying direction of the paper in the post-process apparatus can be decreased.  
         [0039]     Referring to  FIG. 18 , a cross section and an open and close mechanism of the waiting tray parts  10   a  and  10   b  will be described. As shown in  FIG. 18 , a pair of alignment members  71   a  and  71   b  is vertically provided on the lower side surfaces of sheet loading surfaces  10   c  in the waiting tray  10 . A pair of wall members  72   a  and  72   b  is vertically provided on both sides of surfaces of the sheet loading surfaces  10   c  in the waiting tray parts  10   a  and  10   b.    
         [0040]     The alignment members  71   a  and  71   b  are connected to both ends of a rack and pinion mechanism  73 . A stepping motor  75  controls the rotation of a pinion gear  74 , and controller  76  controls the rotation of the stepping motor  75 .  
         [0041]     The sheet post-process apparatus has a paper guide  36 , which guides sheets from the MFP  1  to the waiting tray  10  and thence to the processing tray  12 . The paper guide  36  has a paper-pass ceiling.  
         [0042]     In the processing tray  12 , the sheets are aligned at the longitudinal edges. The sheets are aligned at their longitudinal edges by a longitudinal-alignment mechanism  38  as is illustrated in  FIG. 4 . More precisely, an upper longitudinal-alignment motor  40  drives the upper longitudinal-alignment rollers  38   a  of the mechanism  38 , and a lower longitudinal-alignment motor  42  drives the lower longitudinal-alignment rollers  38   b  of the mechanism  38 . Driven by the motors  40  and  42 , the rollers  38   a  and  38   b  move the sheets until one longitudinal edge of every sheet abuts on a stopper  45 . Paddles  44  are provided to facilitate the longitudinal alignment. A paddle motor  46  drives the paddles  44 .  
         [0043]     When the number of sheets thus aligned in the processing tray  12  reaches the prescribed value, the stapler  14  starts operating. The stapler  14  is positioned as depicted in  FIG. 6  and controlled by a stapler-driving unit  49 .  
         [0044]     Controlled by the unit  49 , the stapler  14  staples the sheets together, forming a bundle of sheets. As shown in  FIG. 4 , a transport mechanism  50  transports the bundle of sheets to the first storage tray  16 . Either the first storage tray  16  or the second storage tray  18  is selected when a storage-tray driving unit  52  moves the tray  16  or  18  to a predetermined upper position.  
         [0045]     How the post-process apparatus according to this invention operates will be explained with reference to FIGS.  7  to  18 .  
         [0046]     As  FIG. 7  shows, a sheet  20  conveyed from the MFP  1  is moved from the input rollers  22  to the sheet-feeding rollers  24 , in the direction of the arrow.  
         [0047]     As is illustrated in  FIG. 8 , the sheet  20 , or the first sheet, is placed on the waiting tray  10 . Then, the waiting-tray rollers  28  move down, in the direction of the arrow, aligning the trailing edge of the first sheet  20  at the rear (i.e., upstream) end  60  of the waiting tray  10 .  
         [0048]     As  FIG. 9  depicts, the waiting-tray rollers  28  moves up to receive the second sheet  20 a.  
         [0049]     As  FIG. 10  shows, the second sheet  20  is conveyed to the waiting tray  10 . The waiting-tray rollers  28  move down, aligning the trailing edge of the second sheet  20   a  at the rear end  60  of the waiting tray  10 . Thus, a bundle  20   b  of two sheets  20  and  20   a  is formed in the waiting tray  10 .  
         [0050]     As  FIG. 11  show, the waiting-tray rollers  28  move upwards. Then, the waiting-tray parts  10   a  and  10   b  move to the opened position as is illustrated in  FIG. 3 . The active drop is therefore performed as shown in  FIG. 12 . The bundle  20   b  is conveyed to the processing tray  12 .  
         [0051]     Referring to  FIG. 19 , a procedure in which the bundle of paper  20   b  loaded on the waiting tray  10  falls down on the processing tray  12  will be described in detail. At first, as shown in  FIG. 19A , the bundle of paper  20   b  is loaded on the waiting tray parts  10   a  and  10   b . As shown in  FIG. 19B , the controller  76  controls the stepping motor  75  to move the waiting tray parts  10   a  and  10   b  toward the direction in which the waiting tray parts  10   a  and  10   b  are separated from each other, and the bundle of paper  20   b  starts the fall-down.  
         [0052]     When the bundle of paper  20   b  falls down, as shown in  FIG. 19C , the controller  76  controls the stepping motor  75  to move the waiting tray parts  10   a  and  10   b  toward the direction in which the waiting tray parts  10   a  and  10   b  are brought close to each other.  
         [0053]     In the procedure in which the bundle of paper  20  falls down, since the waiting tray parts  10   a  and  10   b  are controlled toward the direction in which the waiting tray parts  10   a  and  10   b  are brought close to each other, even if the alignment in the transverse direction of the bundle of paper  20   b  is confused as shown in  FIG. 19C , the alignment in the transverse direction of the bundle of paper  20   b  can be secured by the alignment members  71   a  and  71   b  as shown in  FIG. 19D .  
         [0054]     In controlling the waiting tray parts  10   a  and  10   b  toward the direction in which the waiting tray parts  10   a  and  10   b  are brought close to each other, it is possible that the waiting tray parts  10   a  and  10   b  are brought close to each other while the alignment members  71   a  and  71   b  are slightly moved by repeating the normal rotation and the reverse rotation of the stepping motor  75 . Therefore, a contact surface of the bundle of paper is decreased in a coefficient of kinetic friction, and the transverse alignment can easily be performed.  
         [0055]     Thereafter, as shown in  FIG. 13 , the third sheet  20   c  and some following sheets are conveyed from the sheet-feeding rollers  24  to the processing tray  12 , not through the waiting tray  10 . These sheets are laid, one after another, upon the bundle  20   b  of two sheets. A bundle  21 , which consists of the prescribed number of sheets, is formed on the processing tray  12 . As the sheets including the third sheet  20  are sequentially laid on the bundle  20   b , the longitudinal-alignment rollers  38  and the transverse-alignment mechanism  47  align the sheets at their longitudinal edges and transverse edges.  
         [0056]     It is desired that the waiting tray  10  and the processing tray  12  be inclined, having their upstream ends at a lower position than their downstream ends. In other words, they should be so positioned that their rear ends  60  and  62  lie at the lowest position. If the trays  10  and  12  are so inclined, the sheets  20  are aligned, due to gravity, at the rear end  60  of the waiting tray  10 , and the bundle  20   b  can be aligned, due to gravity, at the rear end and  62  of the processing tray  12 .  
         [0057]     As  FIG. 14  shows, the stapler  14  staples the bundle  21  of sheets. Then, the transport mechanism  50  transports the bundle  21  to the storage tray  16  as illustrated in  FIG. 15 . Thus, the post-process ends.  
         [0058]     If the sheets need not undergo the post-process, they are not conveyed to the processing tray  12 . They are ejected from the waiting tray  10  onto the first storage tray  16  as show in  FIGS. 16 and 17 . As  FIG. 16  shows, the sheets supplied form the MFP  1  are sequentially conveyed to the first storage tray  16  via the input rollers  22 , sheet-feeding rollers  24  and waiting tray  10 . The waiting-tray rollers  28  move down, serving to convey sheets  20 . As depicted in  FIG. 17 , the storage-tray driving unit  52  lifts the first storage tray  16  a little and receives the sheets coming from the waiting tray  10 .  
         [0059]     As shown in  FIG. 5 , it is also possible that a transverse alignment mechanism  47  is provided in the processing tray  12 .  
         [0060]     In the embodiment, the paper is received while the waiting tray parts  10   a  and  10   b  are narrowed. However, it is possible that the paper is received while the waiting tray parts  10   a  and  10   b  are closed.  
         [0061]     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.