Abstract:
A sheet-receiving device has multiple sheet receiving faces on which to receive different print jobs. The print faces are positioned in tandem with respect to each other. Sheets ejected from an apparatus are ejected onto a first of the multiple faces and remain their until moved. If another print job is to be printed, the operator may move the first print job from the first sheet receiving face to the second sheet receiving face simply by sliding the first print job to the second sheet receiving face. The first print job snaps into place, and curled edges of upper sheets in the first print job are blocked by a barrier between the first and second sheet receiving face so that sheets in the first print job do not interfere with the reception of sheets in the second print job.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to imaging devices and paper handling devices having a receiving device for receiving discharged papers from an outlet. More particularly, the present invention may be used with an image forming apparatus such as a digital copier or a facsimile. 
     2. Discussion of the Background 
     Recently in modern office environments, an image forming apparatus, such as a printer, is commonly connected to one or more host machines, such as personal computers. Computer users can perform a printing operation at the printer from any of the personal computers. The printer responds by printing a sheet and then discharging the printed sheet to a sheet receiving device. 
     In above mentioned printer system, there may be a situation in which printed and discharged sheets are left in a receiving tray, for example if the user leaves the printer to pick up a telephone call. In this situation, when another user uses the same printer, the newly printed sheets (i.e., the second print job) are discharged directly on top of the first print job. Stacking the two print jobs in this way gives rise to the possibility that either the first user or the second user will inadvertently take both print jobs when retrieving their print job from the printer. Once the mistake is discovered, the user must sort-out the different print jobs, identify the print job that is not theirs, and insert the other user&#39;s print job back in the printer receiving tray. 
     A conventional sheet-receiving device described in Laid-Open Japanese Utility Model document 57-135541 attempts to address the issue of separating print jobs. As shown in FIG. 16, a printer  90  has a tray  92  for receiving printed sheets from an outlet  91  and a sorting tray  93  that is rotatably mounted by pins  94  at a side of the tray  92  for holding printed sheets from another user&#39;s print job at a location adjacent to the tray  92 . In this case, the user rotates the sorting tray  93  to a horizontal position, as shown by the dotted line, and moves the printed sheets in preparation for the next sheets to discharge. 
     Another conventional sheet-receiving device is described in Japanese Utility Model document 0351752. As shown in FIG. 17, this device includes a receiving tray  82  having a beveled faces  82   a ,  82   b ,  82   c  and  82   d  for pushing printed sheets discharged by rollers  81 , down for each fixed positions  83 , which are located at lower positions of each of the beveled faces  82   a ,  82   b ,  82   c  and  82   d . Overhangs  84  are located at upper positions of the beveled faces  82   a ,  82   b ,  82   c  and  82   d . When sorting printed sheets, the user moves printed sheets that have already printed on the beveled face  82   a  to the next beveled face  82   b . When two print jobs are held on the beveled faces  82   a  and  82   b , the user moves the print jobs to other beveled face  82   c  or  82   d.    
     However, as presently recognized, a problem with the formerly described conventional approach is that the printer has to be positioned in an area that is sufficient far way from a wall or other obstruction that allows the sorting tray  93  to be lowered. The latter approach has a different problem as discussed below. Because of the overhang  84 , as shown in FIG. 18, located at an upper portion of the fixed portion  83 , the user, when sorting, has to slide a bundle of sheets “S” up to the beveled face  82   b . Moreover, the user has to move a rear edge Sb of the sheets S over the overhang  84   a . If a length “L” of the beveled face  82   b  is comparatively shorter against the sheets S, a front edge of the sheets S is suspended and upper sheets of the bundle of papers become warped. Therefore, the sheets S do not easily move down into the pocket of the fixed position  83  easily and requires the user to move the bundle of papers up to the next beveled face before sliding the paper bundle into the fixed position  83 . This situation causes sheets to collide between the moved sheets and the next discharged sheets. Furthermore, when left in the warped position, the sheets take on a habitual curling tendency. 
     On the other hand, if a length L′ of the beveled face  82   b  is comparatively longer than the sheets S, as shown in FIG. 19, the size of the receiving tray  82  increases. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in view of the above-identified problems, and accordingly, an object of the present invention is to provide a sheet receiving device that overcomes the above-identified problems, as well as other problems. To this end, a feature of the novel sheet-receiving device is to provide a configuration that outputs and sorts sheets easily and precisely. 
     Another object of this invention is to provide a novel sheet-receiving device that has a capacity that can change as required. 
     Still another object of this invention is to provide a compact-sized sheet receiving device. 
     These and other objects are achieved with a sheet-receiving device having multiple sheet receiving faces on which to receive different print jobs. The print faces are positioned in tandem with respect to each other. Sheets ejected from an apparatus are ejected onto a first of the multiple faces and remain their until moved. If another print job is to be printed, the operator may move the first print job from the first sheet receiving face to the second sheet receiving face simply by sliding the first print job to the second sheet receiving face. The first print job snaps into place, and curled edges of upper sheets in the first print job are blocked by a barrier between the first and second sheet receiving face so that sheets in the first print job do not interfere with the reception of sheets in the second print job. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
     FIG. 1 is a side view of a printer of first embodiment having sheet-receiving device of this invention; 
     FIG. 2 is a perspective view of the first embodiment; 
     FIG. 3 is a side view of a sheet receiving mechanism of the first embodiment, where sheets are arranged in a first state; 
     FIG. 4 is the same side view as FIG. 3, but sheets are arranged in another state; 
     FIG. 5 is the same side view as FIGS. 3 and 4, where relative positions of two sets of sheets are shown; 
     FIG. 6 is the same side view as FIGS. 3-5, where one of the two sets of sheets is removed from a first tray; 
     FIG. 7 shows a portrait view of a printer according to a second embodiment of this invention; 
     FIG. 8 is a side view of the sheet receiving mechanism of the second embodiment, where relative positions of two sets of sheets are shown; 
     FIG. 9 is a side view of a third embodiment of a sheet receiving mechanism according to the present invention and includes a warp-inhibiting mechanism; 
     FIG. 10 is a side view of a fourth embodiment of a sheet receiving mechanism according to the present invention; 
     FIG. 11 is a side view of a fifth embodiment of a sheet receiving mechanism according to the present invention; 
     FIG. 12 is a side view of a sixth embodiment of a sheet receiving mechanism according to the present invention; 
     FIG. 13 shows a retractable tray feature of the sixth embodiment of the present invention; 
     FIG. 14 is a side view of a seventh embodiment of a sheet receiving mechanism according to the present invention; 
     FIG. 15 is a side view of the seventh embodiment of the sheet receiving mechanism according to the present invention where two sets of sheets are accommodated; 
     FIG. 16 is a perspective view of a conventional printer and sheet receiving mechanism; 
     FIG. 17 is a side view of another conventional sheet receiving mechanism; 
     FIG. 18 is a side view of the sheet receiving mechanism of FIG. 17, where a set of sheets is positioned on the sheet feeding mechanism; and 
     FIG. 19 is another side view of the conventional sheet feeding mechanism of FIG. 17, where a length between sheet holding trays is longer than that shown in FIG.  18 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, FIG. 1 is a side view of a printer having a sheet-receiving device according to a first embodiment of the present invention. FIG. 2 is a perspective view of this embodiment. 
     The printer  1  has a sheet-receiving device  10  on to which ejected sheets from an image forming device, or other device, are discharged. The printed sheets are discharged from an outlet  3  and stacked on a receiving tray  5 , which has a first tray  11  and a second tray  12 . The first tray  11  is located upstream of the second tray  12  in a sheet feeding direction, and a step  6  is placed between the two trays. The step  6  has, as shown in FIG. 3, a thin board  7  (or projection formed) as a warp-inhibiting mechanism for regulating the rear edge of a bundle of printed sheets S 1  so as avoid warped sheets in the stack from extending higher than a top  11   a  of the first tray  11 , because the thin board  7  itself is located at upper portion of the step  6 . Furthermore, the thin board  7  is parallel with a surface of the first tray  11  in normal condition. However, the thin board  7  is made of an elastic material, such as a resin film, so that, as shown in FIG. 4, when an operator slides the sheets S 1  along the first tray  11  and the rear edge Sb of the sheets S 1  is pulled-out from the first tray  11 , the weight of the sheets S 1  is over the thin board  7  so the thin board is folded (i.e., bent or moved down) and the sheets S 1  fit in the second tray  12  in a snapping action. 
     This sheet-receiving device  10  has, as shown in FIG. 2, lower parts  8 ,  9  which are located lower than the receiving tray, so that the operator can easily grasp and remove the printed sheets from the receiving tray  5 . One or more lower parts may be placed on either side of the trays  11 ,  12 . 
     This sheet-receiving device  10  is especially well suited for printers that support connections to several computers by way of a network, for example. That is because when a user operates the computer or word processor to print out from the printer  1  under conditions of which the printer has discharged sheets on the receiving device  10  by other users and goes to the printer to take out his printed sheets, he can pull out the others and put them on the second tray  12  as shown in FIG.  3 . Often there is sufficient time for the user to arrive at the printer before the user&#39;s print job has started. Accordingly, when the user takes out his printed sheets after all of his sheets were discharged, the user can easily distinguish between a bundle of his sheets, e.g. sheets S 2 , and the other bundle of sheets S 1  as both sets of sheets only partially overlap, as shown in FIG.  5 . 
     As mentioned above, as both trays  11 ,  12  are placed on the top of the printer  1 , a layout of the receiving tray  12  looks simple and small in comparison with a printer equipped with a side mounted sorting tray. Furthermore, the existence of sheets on the tray  12  makes the user conveniently aware that the sheets are available for pick-up. 
     Still further, even if the top sheets of the sheets S 1  are warped, as the thin board  7  pushes the back edge Sb of the sheets S 1 , as shown in FIG. 5, a sheet collision between the sheets S 1  and the sheets S 2  does not occur. However, if the thin board  7  is absent or removed, the back edge Sb, if warped, may extend over the top of the first tray  11   a , as shown in FIG.  6 . 
     In this embodiment, a user can conveniently maintain the separation between discrete print jobs by moving a previously printed print job to the next tray simply by sliding the sheets backward and dropping the sheets in the next tray. Moreover, the user need not push the sheets down in the next tray and does not have to move the sheets over the overhang like the sheet-receiving device shown in FIG.  17 . Furthermore, this sheet receiving device is compact in structure as compared to the sheet receiving device having unnecessary length L′ of tray surface shown in FIG.  19 . Adopting this receiving device, the printer, even a small sized printer having a little space in a discharging direction, can mount this sheet receiving device on the top thereof without protrusion of the front-end of the second tray. 
     FIG. 7 shows a perspective view of a medium sized printer according to the second embodiment of this invention. As this printer is larger in comparison with the printer of the first embodiment, a receiving device is larger. Accordingly, the first tray  31  can receive normally sized printed sheets discharged from an outlet  33  without overlap between sheets S 2  in the first tray  31  and sheets S 1  in a second tray  32 , as shown in FIG.  8 . 
     This printer  21  has a lower part  38 , which is lower than a surface  31   a  of the first tray  31  and a surface  32   a  of the second tray  32 , and which is provided on one side of the first tray  31  in a discharging direction shown as an arrow B in FIG. 7. A user, therefore, can grasp and take off the sheets from the first tray  31  or the second tray  32  easily by putting his hand into the lower part  38 . 
     FIG. 9 illustrates a third embodiment of the present invention and includes another type of warp-inhibiting mechanism. This warp-inhibiting mechanism has a protrusion  41  at the top of a step  6 . The protrusion  41  sticks out over the second tray  12  in sheet feeding direction. This protrusion  41  can rotate about a shaft  43  in directions indicated by the arrow G and that is biased in counterclockwise direction by a spring  44 . In normal condition, the protrusion  44  is regulated in degree of turn by a pin  45 . When adding a weight of sheets on the protrusion  44 , the protrusion is turned in a clockwise direction opposing an elasticity of the spring  44 . Consequently, the sheets are moved and fit in the second tray  12  in a snap action. 
     FIG. 10 illustrates a fourth embodiment of this invention and includes a step  6 ′ that has a shape that is different from that of above-mentioned sheet receiving devices. The step  6 ′ has a longitudinal wall  6   a , and that wall  6   a  and a tray surface  12   a  of the second tray  12  form a corner with an acute angle θ (θ&lt;90 degree). As the corner is acute, the wall  6   a  helps the thin board  7  to hold down curled edges of sheets in the second tray  12 . 
     FIG. 11 illustrates a fifth embodiment of this invention, a feature of which is providing a removable tray as a first tray  51  from a receiving tray  5 ′. In this embodiment, when the first tray  51  is pulled from the receiving tray  5 ′, a carrying capacity of the receiving tray  5 ′ increases by an amount of a height H, without an occurrence of sheet deviating or warping. 
     FIG. 12 shows a sixth embodiment of this invention. This receiving device includes a first tray  61  that can rotate about a shaft  61   b  in directions indicated by an arrow C. When the first tray  61  is retracted, for example by the action of a lever (not shown), a surface  61   a  of the first tray  61  becomes nearly equal to a surface  12   a  of the second tray  12  in height, as shown in FIG. 13, and a carrying capacity of the receiving tray  5 ″ increases, as a result. 
     FIG. 14 shows a seventh embodiment of this invention. This receiving device has a first tray  61 ′, which can rotate about a shaft  61   b  and which is lifted up by a spring  72 . When sheets S are gradually stacked on the first tray  61 ′, the first tray  61 ′ is urged down by the weight of the sheets S and a carrying capacity of the first tray  6 ′ increases in response to the amount of the sheets S. Furthermore, even if a user has sorted and put prior sheets on a second tray  12  before this receiving, a protrusion  41  makes a distinction between the sheets S 2  and the sheets S 1  with reliability, as shown in the circled region in FIG.  15 . As a consequence, the protrusion delineates the two sets of sheets. 
     The above mentioned embodiments are explained in detail for the case of a printer. However, this invention can be applied to other image forming apparatuses, and other devices that involve processing sheets of paper or the like. 
     The present document is based on Japanese Patent Application Nos. 09-308312, filed in Japan on Nov. 11, 1997, and 10-240507, filed in Japan on Aug. 26, 1998, the entire contents of both of which being incorporated herein by reference. 
     Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.