Patent Publication Number: US-2009238623-A1

Title: Image forming apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application is based on and claims priority pursuant to 35 U.S.C. §119 from Japanese Patent Application No. 2008-069664 filed on Mar. 18, 2008 in the Japan Patent Office, the entire contents of which are hereby incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Exemplary aspects of the present invention generally relate to an image forming apparatus, such as a copier, a facsimile machine, a printer, or a digital multifunction system including a combination of at least two of these functions. 
     2. Description of the Background Art 
     In a generally-known electrophotographic image forming apparatus such as a copier, an original document is read by a document reader provided substantially at an upper portion of the image forming apparatus. Based on image information read by the document reader, an image is optically written on a surface of a photoreceptor drum in an image forming unit so as to form an electrostatic latent image on the photoreceptor drum. 
     Subsequently, the electrostatic latent image on the photoreceptor drum is developed with toner into a visible image, also known as a toner image. Thereafter, in a transfer unit, the visible image is transferred onto a recording medium such as a paper sheet or the like. 
     Subsequently, the unfixed toner image on the recording medium is fixed and discharged onto a sheet receiving tray provided at a side surface of the image forming apparatus. 
     A drawback to the foregoing configuration is that, because the sheet receiving tray sticks out from the side surface of the image forming apparatus, the image forming apparatus as a whole occupies a relatively large space, thus limiting flexibility in the choice of locations for the image forming apparatus in an office, for example. 
     In view of the above, an image forming apparatus capable of receiving the discharged recording medium inside a space defined by the main body of the image forming apparatus to reduce its overall footprint is proposed. 
     In such an image forming apparatus, the recording medium after the image is fixed thereon is discharged to a discharged sheet receiver provided in a space between the document reader and the image forming unit. In other words, the recording medium is discharged substantially below the document reader but substantially above the image forming unit. The discharged sheet receiver receives and stores the discharged sheet. 
     Such an image forming apparatus that discharges the recording sheet internally positions the image forming unit substantially at the center of the image forming apparatus. A plurality of sheet feed cassettes is provided substantially below the image forming unit. The document reader is provided substantially above the image forming unit, defining a space therebetween. Generally, three sides of the discharged sheet receiver, except for a front side corresponding to the front side of the image forming apparatus, are enclosed by sides, or walls, of the image forming apparatus. 
     In order to be able to accommodate a connection with a finisher and so forth, an image forming apparatus in which, in addition to the front side of the discharged sheet receiver, a side of the discharged sheet receiver in a sheet discharge direction is not covered by the wall of the image forming apparatus, is also proposed. 
     With reference to  FIG. 1 , a description is provided of the generally-known image forming apparatus that discharges the recording sheet internally.  FIG. 1  is a schematic diagram illustrating a related-art internal sheet discharge portion of the image forming apparatus. 
     As illustrated in  FIG. 1 , an image reader (scanner)  514  is provided substantially above an internal sheet discharge portion  512  (hereinafter simply referred to as a sheet discharge portion). An image forming unit (printing portion)  510  is provided substantially below the sheet discharge portion  512 . In other words, between the image reader  514  and the image forming unit  510 , the sheet discharge portion  512  is provided. 
     The recording medium, on which an image is transferred in the image forming unit  510 , is transported to a fixing device through a sheet transport path. After the image is fixed onto the recording medium, the recording medium is discharged to the sheet discharge portion  512  by a sheet discharge roller  545  serving as a first sheet discharge device. 
     Subsequently, the discharged recording sheet is stacked onto a sheet receiver  500 . 
     A drawback to this configuration illustrated in  FIG. 1  is that the sheet discharge portion  512  is located between the image reader  514  and the image forming unit  510 , and the recording sheet is discharged on a bottom surface of the sheet discharge portion  512  so that the image reader  514  prevents a standing user of the image forming apparatus from seeing the discharged recording sheet well. 
     Furthermore, since the image reader  514  is provided substantially at the upper portion of the image forming apparatus, the user either needs to lean forward to retrieve the discharged recording medium on which the image is formed from the sheet receiver  500  or is obliged to retrieve the recording medium without being able to see well the discharged recording sheet. 
     Consequently, with this configuration, although the purpose of achieving reduction in the size of the image forming apparatus as a whole can be satisfied, there is a drawback in terms of usability for the user. 
     SUMMARY OF THE INVENTION 
     Illustrative embodiments of the present invention provide an image forming apparatus that allows a user to pick up a discharged sheet with ease. 
     In view of the foregoing, in one illustrative embodiment of the present invention, an image forming apparatus for forming an image includes an image reader, an image forming unit, a sheet discharge device, a sheet receiver, and a sheet moving mechanism. The image reader is provided substantially at an upper portion of the image forming apparatus and configured to read an image of a document. The image forming unit is disposed substantially below the image reader through some space and is configured to form an image based on image information read by the image reader and transfer the image onto a recording medium. The sheet discharge device is configured to discharge the recording medium on which an image is formed. The sheet receiver is provided in the space between an upper portion of the image forming unit and a bottom portion of the image reader and configured to receive the recording medium discharged by the sheet discharge device. The sheet moving mechanism is configured to move the recording medium that is discharged onto the sheet receiver by the sheet discharge device in a desired direction. 
     Additional features and advantages of the present invention will be more fully apparent from the following detailed description of illustrative embodiments, the accompanying drawings and the associated claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description of illustrative embodiments when considered in connection with the accompanying drawings, wherein: 
         FIG. 1  is a schematic diagram illustrating a related art sheet discharge portion of an image forming apparatus; 
         FIG. 2  is a perspective view of an electrophotographic color copier as an example of an image forming apparatus as viewed from a substantially front upper right thereof according to an illustrative embodiment of the present invention; 
         FIG. 3  is a perspective view of the image forming apparatus of  FIG. 2  as viewed from a substantially front upper left thereof according to an illustrative embodiment of the present invention; 
         FIG. 4  is a schematic diagram illustrating inside the image forming apparatus according to an illustrative embodiment of the present invention; 
         FIG. 5  is a schematic diagram illustrating a sheet discharge portion of the image forming apparatus according to a first illustrative embodiment of the present invention; 
         FIG. 6  is a schematic diagram illustrating a sheet discharge portion of the image forming apparatus according to a second illustrative embodiment of the present invention; 
         FIG. 7  is a schematic diagram illustrating a sheet discharge portion of the image forming apparatus according to a third illustrative embodiment of the present invention; 
         FIG. 8  is a schematic diagram illustrating a sheet discharge portion of the image forming apparatus according to a fourth illustrative embodiment of the present invention; 
         FIG. 9  is a schematic diagram illustrating a sheet discharge portion of the image forming apparatus according to a fifth illustrative embodiment of the present invention; 
         FIG. 10  is a schematic diagram illustrating a sheet discharge portion of the image forming apparatus according to a sixth illustrative embodiment of the present invention; and 
         FIG. 11  is a schematic diagram illustrating a sheet discharge portion of the image forming apparatus according to a seventh illustrative embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     In describing illustrative embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner and achieve a similar result. 
     Illustrative embodiments of the present invention are now described below with reference to the accompanying drawings. 
     In a later-described comparative example, illustrative embodiment, and alternative example, for the sake of simplicity of drawings and descriptions, the same reference numerals will be given to constituent elements such as parts and materials having the same functions, and redundant descriptions thereof omitted. 
     Typically, but not necessarily, paper is the medium from which is made a sheet on which an image is to be formed. It should be noted, however, that other printable media are available in sheet form, and accordingly their use here is included. Thus, solely for simplicity, although this Detailed Description section refers to paper, sheets thereof, paper feeder, etc., it should be understood that the sheets, etc., are not limited only to paper, but includes other printable media as well. 
     Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, and initially to  FIG. 1 , one example of an image forming apparatus according to an illustrative embodiment of the present invention is described. 
     Referring now to  FIGS. 2 and 3 , there are provided perspective views of an electrophotographic color copier as an example of an image forming apparatus according to the illustrative embodiment.  FIG. 2  illustrates an image forming apparatus  10  as viewed from a substantially front upper right of the image forming apparatus  10 .  FIG. 3  illustrates the image forming apparatus  10  as viewed from a substantially front upper left thereof. 
     As illustrated in  FIGS. 2 and 3 , the image forming apparatus  10  includes an image forming unit  110 , a sheet feeder  111 , an internal sheet discharge portion  112 , a duplex unit  113 , an image reader  114 , a control panel  115  including a display panel and operation buttons, and so forth. 
     The image forming unit  110  forms and transfers an image onto a recording medium. Substantially below the image forming unit  110 , the sheet feeder  111  that stores a stack of recording media sheets is disposed. The sheet feeder  111  picks up the recording medium one sheet at a time and sends the recording medium to the image forming unit  110 . 
     The internal sheet discharge unit  112  discharges the recording medium on which an image is recorded. When an image is formed on the other side of the recording medium as well, the duplex unit  113  turns over the recording medium and sends the recording medium to the image forming unit  110  again. 
     The image reading unit  114  includes a contact glass on which an original document is placed and reads an image of the document. 
     Referring now to  FIG. 4 , there is provided a schematic diagram illustrating inside the image forming apparatus  10 . The image forming apparatus  10  illustrated in  FIG. 4  is a color copier as an example of the image forming apparatus. 
     The image forming unit  110  of the image forming apparatus  10  includes four image forming stations A, B, C, and D, a primary transfer unit E, a secondary transfer unit F, a sheet transport device G, a fixing device H, a toner feeding device J, and so forth. 
     The four image forming stations A, B, C, and D forms an image of yellow (Y), magenta (M), cyan (C), and black (K), respectively, using respective colors of toner. Each of the image forming stations A, B, C, and D includes a drum-type photoreceptor  12 A,  12 B,  12 C, and  12 D, each of which serves as an image bearing member. The photoreceptor drums  12 A,  12 B,  12 C, and  12 D are rotatably supported and arranged in tandem. 
     Around each of the photoreceptor drums  12 A,  12 B,  12 C, and  12 D, a charging device  13 , a developing device  14 , a transfer member  15  disposed opposite the photoreceptor drum  12 , a cleaning device  16 , and a charge neutralizer  17  are provided. 
     Substantially below the image forming stations A, B, C, and D, an exposure unit  18  is provided so as to expose each of the photoreceptor drums  12 A,  12 B,  12 C, and  12 D. 
     It is to be noted that the image forming stations A, B, C, and D have the same configuration as all the others, differing only in the color of toner employed. Similarly, the photoreceptor drums  12 A,  12 B,  12 C, and  12 D have the same configuration as all the others, differing only in the color of toner employed. 
     For simplicity, a description will be provided of the image forming station A and the photoreceptor drum  12 A as a representative example, unless otherwise specified. 
     The exposure unit  18  illuminates the surface of the photoreceptor drum  12 A with a laser beam emitted from a light source using optical parts, not illustrated. The exposure unit  18  optically scans the surface of the photoreceptor drum  12 A and optically writes forming a latent image thereon. 
     The primary transfer unit E serves as a primary image bearing mechanism and includes a primary image bearing member  20 , three primary transfer rollers  21 ,  22 , and  23 , a primary cleaning unit  24 , and a primary transfer member  25 . 
     The primary image bearing member  20  is a belt member that contacts each of the photoreceptor drums  12 A through  12 D and is sandwiched between each of the photoreceptor drums  12 A through  12 D and the respective transfer members  15 . The primary image bearing member  20  is wound around and stretched by the primary transfer rollers  21 ,  22 , and  23 . 
     The primary cleaning unit  24  and the primary transfer member  25  are disposed in the vicinity of the primary image bearing member  20 . 
     The secondary transfer unit F serves as a secondary image bearing mechanism and includes a secondary image bearing member  30 , three secondary rollers  32 ,  33 , and  34 , a secondary cleaning unit  35 , and a secondary transfer device  36 . 
     The secondary image bearing member  30  is a belt member that contacts the primary image bearing member  20 , thereby forming a transfer nip therebetween. The secondary image bearing member  30  is wound around and stretched by the secondary rollers  32 ,  33 , and  34 , and passes between the primary image bearing member  20  and the primary transfer member  25 . 
     The secondary cleaning unit  35  and the secondary transfer device  36  are disposed in the vicinity of the secondary roller  32 . 
     The sheet transport device G that transports the recording medium P includes a sheet transport path that extends upward from substantially the bottom of the image forming apparatus  10 . The sheet transport path is provided between the primary transfer unit E and the secondary transfer unit F. 
     The sheet transport device G includes sheet cassettes  40 , sheet feed rollers  41 , sheet guide members  42 , a pair of registration rollers  43 , sheet discharge guide members  44 , a pair of sheet discharge rollers  45 , and so forth. According to the illustrative embodiment, two pairs of the sheet discharge rollers  45  are provided. 
     The sheet cassettes  40  consist of a top and a bottom cassettes, each of which stores a plurality of recording media sheets. Each of the sheet cassettes  40  is equipped with the sheet feed roller  41  that picks up and sends the recording medium P from the sheet cassette  40  one sheet at a time. 
     The sheet guide members  42  guide the recording medium P fed by the sheet feed roller  41  to the pair of registration rollers  43 . Subsequently, the pair of registration rollers  43  directs the recording medium P guided from the sheet guide members  42  to the transfer nip such that the tip of the recording medium P contacts the transfer nip and stops. Then, the position of the recording medium is aligned. 
     Subsequently, the recording medium is sent in appropriate timing such that the recording medium P is aligned with the image formed on the secondary image bearing member  30 . 
     The sheet discharge guide members  44  guide the recording medium P to the sheet discharge rollers  45  after the image on the recording medium P is fixed thereon. The sheet discharge rollers  45  serve as a sheet discharge device and discharge the recording medium P guided by the sheet discharge guide members  44  to the internal sheet discharge portion  112  in a direction indicated by arrow a. 
     It is to be noted that the direction indicated by arrow a is substantially the same as a first sheet discharge direction indicated by arrow  133  described later. 
     The fixing device H includes a pair of heating rollers  47  and fixes an image transferred onto the recording medium P from the primary transfer unit E and the secondary transfer unit F. 
     The toner feeding device J includes a toner storage unit  52  that is equipped with toner cartridges  53  of each color. The toner feeding device J supplies respective color of fresh toner to the image forming stations A, B, C, and D using pumps. 
     In the image forming apparatus  10 , when forming a color image on both sides of the recording medium P, the original document is placed on the contact glass of the image reader  114  and a start button of the control panel  115  is pressed by the user. 
     Subsequently, the photoreceptor drums  12 A,  12 B,  12 C, and  12 D, one of the primary rollers  21 ,  22 , and  23 , one of the secondary rollers  32 ,  33 , and  34 , the sheet feed roller  41 , and so forth start to rotate at proper timing. 
     In the image forming station A, as the photoreceptor drum  12 A starts to rotate in a clockwise direction indicated by arrow, the charging device  13  evenly charges the surface of the photoreceptor drum  12 A. The exposure unit  18  illuminates the photoreceptor drum  12 A with a laser beam designated for the respective color of toner, in this case, yellow, thereby forming a latent image on the photoreceptor drum  12 A. 
     Subsequently, the developing device  14 A develops the latent image formed on the photoreceptor drums  12 A by adhering yellow toner thereto, thereby forming a toner image of yellow. Similarly, toner images of different colors magenta, cyan, and black are formed on the photoreceptor drums  12 B,  12 C, and  12 D. 
     In the primary transfer unit E, one of the primary rollers  21 ,  22 , and  23  is driven to rotate and the other two rollers follow to rotate. The primary image bearing member  20  is rotated in a counterclockwise direction indicated by arrow in synchronization with rotation of the photoreceptor drums  12 A through  12 D. 
     While the primary image bearing member  20  rotates, bias voltage is applied thereto by the transfer members  15 A through  15 D so as to overlappingly transfer the toner image formed on each of the photoreceptor drums  12 A,  12 B,  12 C, and  12 D onto the primary image bearing member  20 . Accordingly, a composite full-color primary image is formed. 
     After the image is transferred, toner remaining on the photoreceptor drum  12 A of the image forming station A, hereinafter referred to as residual toner, is removed from the photoreceptor drum  12 A by the cleaning device  16 A. Subsequently, charge of the photoreceptor drum  12 A is neutralized by the charge neutralizer  17 A in preparation for the subsequent image forming cycle. 
     Subsequently, the photoreceptor drum  12 A is charged by the charging device  13 A, and exposed and optically written by the exposure unit  18 , forming a latent image on the photoreceptor drum  12 A again. 
     The latent image on the photoreceptor drum  12 A is developed by the developing device  14 A with toner, thereby forming a visible image (toner image) on the photoreceptor drum  12 A. 
     It is to be noted that the same image forming cycle is performed in the image forming stations B, C, and D. 
     In the secondary transfer unit F, one of the secondary rollers  32 ,  33 , and  34  is driven to rotate, and the other two rollers follow to rotate. The secondary image bearing member  30  is rotated in the clockwise direction in synchronization with rotation of the primary image bearing member  20 . 
     The secondary image bearing member  30  is applied with bias voltage by the primary transfer member  25  so that the image on the primary image bearing member  20  is transferred onto the secondary image bearing member  30 . 
     At this time, the secondary cleaning unit  35  turns about a shaft  56  to separate from the secondary image bearing member  30 . This state is referred to as a non-cleaning state. 
     After the image is transferred from the primary image bearing member  20  of the primary transfer unit E to the secondary image bearing member  30 , the residual toner is electrostatically removed from the primary image bearing member  20  by the primary cleaning unit  24 . 
     Subsequently, the images on the photoreceptor drums  12 A through  12 D are sequentially transferred onto the primary image bearing member  20  by the transfer members  15 A through  15 D. Accordingly, a second four-color full image is formed. 
     After the image is transferred, the residual toner remaining on the photoreceptor drum  12 A of the image forming station A is removed from the photoreceptor drum  12 A by the cleaning device  16 A. Subsequently, charge of the photoreceptor drum  12 A is neutralized by the charge neutralizer  17 A in preparation for the subsequent image forming cycle. 
     In the sheet transport device G, one of the sheet feed rollers  41  is selectively rotated so as to pick up and send the recording medium P stored in the sheet cassette  40  to the sheet guide members  42 . The sheet guide members  42  guide the recording medium P such that the tip of the recording medium P arrives between the registration rollers  43  and stops. 
     Subsequently, the registration rollers  43  are rotated so as to send the recording medium P to the transfer nip between the primary image bearing member  20  and the secondary image bearing member  30  in appropriate timing such that the recording medium P is aligned with the first full-color image and the second full-color image described above. 
     Next, in the transfer nip, bias voltage is applied by the primary transfer member  25  from the rear surface of the recording medium P so as to transfer the second full-color image on the primary image bearing member  20  onto the front surface of the recording medium P. Then, the recording medium P is transported upward by a small amount. 
     Subsequently, bias voltage is applied from the front surface of the recording medium P by the secondary transfer device  36  so as to transfer the first full-color image on the secondary image bearing member  30  onto the rear surface of the recording medium P. 
     After the image is transferred on both sides of the recording medium P, the recording medium P is sent to the fixing device H. In the fixing device H, the recording medium P passes between the pair of the heating rollers  47  that applies heat and pressure to the image on the recording medium P, thereby fixing the image onto both sides of the recording medium P. 
     After fixing, the sheet discharge guide members  44  guide the recording medium P to switching claws, not illustrated, that direct the recording medium P to the appropriate pair of sheet discharge rollers  45 . 
     The selected pair of the sheet discharge rollers  45  discharges the recording medium P face-down outside the housing of the image forming apparatus  10 , onto a sheet receiver  50  of the internal sheet discharge portion  112 . 
     After the image is transferred, the residual toner is removed from the primary image bearing member  20  of the primary transfer unit E by the primary cleaning unit  24 . 
     The residual toner is removed from the secondary image bearing member  30  of the secondary transfer unit F such that the secondary cleaning unit  35  is turned about the shaft  56  so as to contact and clean the secondary image bearing member  30  in preparation for the subsequent image forming cycle. 
     When the toner in the developing devices  14 A through  14 D is consumed, the same color of toner is supplied from the toner cartridges  53  of the corresponding color in the toner storage unit  52  of the toner feeding device J using the pumps. 
     When paper jams occur, preventing transport of the recording medium P, the duplex unit  113  can be opened about a shaft  55  in a direction indicated by arrow d, thereby allowing the sheet transport path to become accessible for maintenance. 
     In a case in which a color image is formed only on one side of the recording medium P, images formed on the photoreceptor drums  12 A through  12 D in the image forming stations A through D are transferred onto the primary image bearing member  20  of the primary transfer unit E. 
     Subsequently, without transferring the image onto the secondary image bearing member  30  of the secondary transfer unit F, the image on the primary image bearing member  20  is directly transferred onto one side of the recording medium P being transported by the sheet transport device G. 
     Then, the image is fixed onto the recording medium P by the fixing device H. The recording medium P, onto which the image is fixed, is discharged face-down and sequentially collated onto the sheet receiver  50 . 
     By contrast, when the image forming apparatus  10  forms a two-color image or a monochrome image on the recording medium P, the corresponding color of image forming station(s) among the image forming stations A through D is employed to form the image, and the image is transferred onto the recording medium P through the primary image bearing member  20  of the primary transfer unit E and the secondary image bearing member  30  of the secondary transfer unit F. 
     A description is now provided of the internal sheet discharge portion  112  according to the illustrative embodiment of the present invention with reference to accompanying drawings. 
     It is to be noted that the following description pertains to the pair of sheet discharge rollers  45 . However, the number of the sheet discharge rollers  45  is not limited to a single pair. Alternatively, two pairs of the sheet discharge rollers  45  can be provided, and the same effect as that of the other embodiments can be achieved. 
     Embodiment 1 
     Referring now to  FIG. 5 , there is provided a schematic diagram illustrating the internal sheet discharge portion  112  of the image forming apparatus  10  according to one illustrative embodiment of the present invention. 
     As illustrated in  FIG. 5 , the image reader (scanner)  114  is provided substantially above the internal sheet discharge portion  112  in the image forming apparatus  10 . Substantially below the internal sheet discharge portion  112 , the image forming unit  110  (printing portion) is provided. In other words, the internal sheet discharge portion  112  is provided between the image reader  114  and the image forming unit  110 . 
     After an image is formed on a recording medium  130  in the image forming unit  110 , although not illustrated in  FIG. 5 , the recording medium  130  is transported along a lateral sheet transport path from the image forming unit  110  to the fixing device H. 
     After the image is fixed onto the recording medium  130 , the recording medium  130  is discharged to the internal sheet discharge portion  112  through the pair of the sheet discharge rollers  45 . 
     The recording medium  130  discharged to the internal sheet discharge portion  112  is stacked on the sheet receiver  50  of the internal sheet discharge portion  112  due to gravity. 
     On the upper surface of the sheet receiver  50 , an endless sheet transport belt  131  serving as a sheet moving device is provided. The sheet transport belt  131  rotates in a direction indicated by arrow  134 , that is, a direction toward a front or proximal side  135  closest to the user. 
     The sheet transport belt  131  is stretched between two pulleys, not illustrated. The pulleys are disposed parallel to one another in the direction of sheet discharge. 
     As the sheet transport belt  131  rotates in the direction of arrow  134 , the recording medium  130  is transported in the direction of arrow  134 , that is, a second sheet discharge direction. The sheet transport belt  131  is driven by a motor, not illustrated. The motor is driven in accordance with an instruction from a control circuit, not illustrated. 
     The direction indicated by arrow  134  is substantially perpendicular to the direction indicated by arrow  133 , that is, a first sheet discharge direction. Accordingly, the recording medium  130  discharged in the direction indicated by arrow  133 , the first sheet discharge direction, is then directed in the direction of arrow  134 , that is, the second sheet discharge direction, thereby enabling the recording medium  130  to move forward and project from the front side  135 . 
     An amount of the projection of the recording medium  130  is preferably, for example, an amount that allows a user to pick up the recording medium  130  by his or her fingers from the front side of the image forming apparatus  10 . 
     Alternatively, in order to accommodate traveling of the recording medium  130 , the sheet receiver  50  can be extended in a projecting manner from the front portion or the proximal end of the image forming apparatus  10  by a predetermined amount. The projecting portion of the sheet receiver  50  is indicated by a reference number  136 . 
     When the projection  136  is provided, a ground-projected area increases by an amount of the projection  136 . However, the projection  136  is at the front side or the proximal end of the image forming apparatus  10 . Therefore, the image forming apparatus  10  can still be installed next to or in the vicinity of a wall or other equipment, and operability by the user can also be assured. 
     The recording medium  130  is moved to the front side of the image forming apparatus  10  when a job requested by the user is completed. In a case in which image forming operation is performed on a plurality of the recording media in a single job, the plurality of recording media is not moved to the front side until the image forming operation on all the plurality of recording media in the job is completed. 
     When the recording medium  130  discharged to the internal sheet discharge portion  112  is then transported substantially to the front side or the proximal end closest to the user, the recording medium  130  can be easily seen by the user, thereby facilitating the user taking out the recording medium  130  from the internal sheet discharge portion  112 . 
     According to the illustrative embodiment, the description is provided of a copier as one example of an image forming apparatus. However, the image forming apparatus is not limited to the copier. The same effect as that of the foregoing description can be achieved when the present invention is applied to a printer and a facsimile machine. 
     Embodiment 2 
     Referring now to  FIG. 6 , there is provided a schematic diagram illustrating the internal sheet discharge portion  112  of the image forming apparatus  10  according to a variation of the foregoing embodiment. 
     According to the present embodiment, a sheet discharge roller  137  is provided in place of the sheet transport belt  131 . The sheet discharge roller  137  is driven by a motor, not illustrated, and enabled to move the recording medium  130  substantially to the front side or the proximal end closest to the user. With this configuration, the same effect as that of the foregoing embodiment can be achieved. 
     It is to be noted that, except for the sheet discharge roller  137 , each component according to the present embodiment is the same and has the same function as that of the foregoing embodiment, unless otherwise specified. 
     Embodiment 3 
     Referring now to  FIG. 7 , there is provided a schematic diagram illustrating the internal sheet discharge portion  112  of the image forming apparatus  10  according to a variation of the foregoing embodiments. 
     According to the present embodiment, a push member  138  is provided in place of the sheet transport belt  131  of Embodiment 1. 
     The push member  138  is configured to move the recording medium  130  from substantially the back of the internal sheet discharge portion  112  to the front side or the proximal end closest to the user. 
     Configuration for moving the push member  138  to the front side includes, but is not limited to, a screw driven by a motor, using a linear motor, using magnetic force, and so forth. Any other suitable driving devices can be employed. 
     It is to be noted that, except for the push member  138 , each component according to the present embodiment is the same and has the same function as that of the foregoing embodiment, unless otherwise specified. 
     Embodiment 4 
     Referring now to  FIG. 8 , there is provided a schematic diagram illustrating the internal sheet discharge portion  112  of the image forming apparatus  10  according to a variation of the foregoing embodiments. 
     According to the present embodiment, the sheet receiver  50  includes a sloped surface  139 . 
     The sloped surface  139  is provided such that a substantially front side of the sheet receiver  50  is tilted downward. With this configuration, when the recording medium  130  is discharged onto the sloped surface  139  of the sheet receiver  50  in the first sheet discharge direction  133 , the recording medium  130 , then, naturally travels in the second sheet discharge direction  134  due to gravity. Accordingly, the recording sheet  130  approaches the front side of the sheet receiver  50  of the image forming apparatus  10 , that is, toward the user. 
     According to the present embodiment, as illustrated in  FIG. 8 , the sloped surface  139  of the sheet receiver  50  has a substantially curved surface instead of a flat surface. By contrast, the front side  135  has a substantially horizontal surface. 
     When the sloped surface  139  is curved and the front side  135  has a horizontal surface, the front end of the recording medium  130 , that is, the leading end of the recording medium  130  in the direction of travel, is prevented from traveling further due to frictional force, thereby preventing the recording medium  130  from falling off from the sheet receiver  50 . 
     Accordingly, the recording medium  130  is moved to, but stopped at a position where the user can easily grasp the recording medium  130 . 
     With this configuration, the devices such as the motor, the sheet transport belt  131 , the sheet discharge roller  137 , the push member  138 , dedicated for moving the recording medium  130 , are not necessitated, thereby reducing initial and running cost and thus achieving the most economical device. 
     It is to be noted that, except for the sloped surface  139 , each component according to the present embodiment is the same and has the same function as that of the foregoing embodiment, unless otherwise specified. 
     Embodiment 5 
     Referring now to  FIG. 9 , there is provided a schematic diagram illustrating the internal sheet discharge portion  112  of the image forming apparatus  10  according to a variation of the foregoing embodiments. 
     According to the present embodiment, a movable sheet discharge tray  140  is provided in place of the sheet transport belt  131  of Embodiment 1. The discharge tray  140  is movable and the size thereof is small enough to fit in the sheet discharge portion  112  when the discharge tray  140  is in a retracted position in the sheet discharge portion  112 . 
     When the sheet discharge tray  140  is in the retracted position in the sheet discharge portion  112 , the sheet discharge tray  140  is within the projected area as viewed from substantially the top of the image forming apparatus  10 . 
     Since the discharge tray  140  is movable, there is no need to provide a projecting portion such as the projection  136  that facilitates the user to grasp the recording medium  130 . 
     According to the present embodiment, the sheet discharge tray  140  is mounted on two rollers such as the sheet discharge roller  137  of Embodiment 2. Such rollers are provided parallel to one another, one substantially at the front side of the sheet receiver  50  of the internal sheet discharge portion  112  and the other substantially at the back thereof. 
     When mounted on the rollers, the sheet discharge tray  140  is able to reciprocally move in the direction of sheet discharge that is perpendicular to the first sheet discharge direction  133 . 
     Furthermore, similar to the push member  138 , configuration for driving the sheet discharge tray  140  includes, but is not limited to, a screw driven by a motor, using a linear motor, using magnetic force, and so forth. Any other suitable driving mechanism can be employed. 
     The sheet discharge tray  140  is moved to the front for each job (each operation) instructed by the user. Before the subsequent job is initiated, that is, before the same user starts printing operation of another document, or before a different user starts printing operation, the sheet discharge tray  140  moves to the front so as to transport the recording medium  130  to the front and the subsequent printing operation is initiated. 
     The sheet discharge tray  140  is retracted back to the internal sheet discharge portion  112  before the next first sheet is discharged. 
     Alternatively, the sheet discharge tray  140  is moved to the front when one user completes his or her printing operation, and the sheet discharge tray  140  is retracted back after the user picks up the recording medium  130  from the sheet discharge tray  140 . 
     The timing of the reciprocal movement of the sheet discharge tray  140  can be determined by the user through the control panel. In other words, the timing with which the sheet discharge tray  140  moves to the front in the second sheet discharge direction and retracts back can be set from the control panel of the image forming apparatus  10  by the user. 
     It is to be noted that, without limitation to the present embodiment; the timing with which the recording medium  130  discharged onto the sheet receiver  50  is moved in the second sheet discharge direction  134  can be set from the control panel by the user. 
     It is to be noted that, except for the sheet discharge tray  140 , each component according to the present embodiment is the same and has the same function as that of the foregoing embodiment, unless otherwise specified. 
     Embodiment 6 
     Referring now to  FIG. 10 , there is provided a schematic diagram illustrating the internal sheet discharge portion  112  of the image forming apparatus  10  according to a variation of the foregoing embodiments. 
     According to the present embodiment, a sheet discharge tray  141  includes a notch  142  at a front corner of the sheet discharge tray  141 . The size of the notch  142  is large enough for a finger or a hand of the user to fit, while being small enough to prevent the recording sheet  130  from falling off from the sheet discharge tray  141  or from being deformed. 
     It is to be noted that the except for the sheet discharge tray  140 , each component according to the present embodiment is the same and has the same function as that of the foregoing embodiments 1 and 5, unless otherwise specified. 
     Embodiment 7 
     Referring now to  FIG. 11 , there is provided a schematic diagram illustrating the internal sheet discharge portion  112  of the image forming apparatus  10  according to a variation of the foregoing embodiments. 
     According to the present embodiment, the recording medium  130  is discharged in a third sheet discharge direction indicated by arrow  144  in addition to the first sheet discharge direction  133  and the second sheet discharge direction  134 . 
     In order to satisfy the purpose of reducing the footprint of the image forming apparatus  10  in which the recording medium is discharged internally, the foregoing embodiments assume that the recording medium  130  is taken out by the user only from the front side of the image forming apparatus  10 , that is, the side from which the user operates. 
     In general, in this type of the image forming apparatus in which the recording medium is discharged internally as illustrated in  FIGS. 2 and 3 , the front and the left sides of the internal sheet discharge portion  112  as viewed from the front are open so that the recording medium  130  can be retrieved therefrom. The front side  135  in  FIG. 11  is the equivalent of the front side at which the user operates in  FIGS. 2 and 3 . A left side  145  in  FIG. 11  is the equivalent of the left side as viewed from the front side in  FIGS. 2 and 3 . 
     In other words, when the left side  145  of the image forming apparatus  10  is not next to or in the vicinity of an object such as a wall, other devices, and so forth, the recording medium  130  can be retrieved from the left side  145 . 
     In such a case also, the recording medium  130  is discharged onto the sheet receiver  50  in the internal sheet discharge portion  112 . In particular, when the size of the recording medium  130  is relatively small, the leading end of the recording medium  130  is discharged to a place away from the opening at the left side  145 , thereby making it difficult for the user to reach the recording medium  130 . 
     In view of the above, according to the present embodiment, a plurality of sheet discharge rollers  143  is provided to the sheet receiver  50  in addition to the sheet discharge roller  137  so as to move the recording medium  130  once discharged onto the sheet receiver  50  further in the third sheet discharge direction  144 . 
     The sheet discharge roller  137  is hereinafter referred to as a first sheet discharge roller  137 . The plurality of the sheet discharge rollers  143  is hereinafter referred to as second sheet discharge rollers  143 . 
     It is to be noted that the third sheet discharge direction  144  is substantially the same direction as the first sheet discharge direction  133 . However, the third sheet discharge direction  144  refers to the discharge direction of the recording medium  130  after the recording medium  130  is discharged onto the sheet receiver  50 . 
     The plurality of the second sheet discharge rollers  143  rotate parallel to the first sheet discharge direction  133 . 
     The first sheet discharge roller  137  and the plurality of the second sheet discharge rollers  143  are disposed such that the first sheet discharge roller  137  and the plurality of the second sheet discharge rollers  143  project by substantially the same amount from the upper surface of the sheet receiver  50  so as to contact the bottom surface of the recording medium  130 . 
     Rotation axes of the plurality of the second sheet discharge rollers  143  are disposed in a direction perpendicular to the first sheet discharge direction  133 . In other words, the rotation axes of the plurality of the second sheet discharge rollers  143  are perpendicular to a rotation axis of the first sheet discharge roller  137 . 
     When the plurality of the second sheet discharge rollers  143  is rotated by a predetermined amount, the recording medium  130  can be transported in the third sheet direction  144  by the predetermined or a desired amount so that the recording medium  130  can be taken out from the left side  145 . 
     The amount by which the recording medium  130  is moved in the third sheet discharge direction  144  varies depending on the size of the recording medium  130 . In other words, the amount by which the recording medium  130  is moved varies depending on the distance between the leading end of the recording medium  130  and the opening at the left side  145 . 
     Therefore, depending on the distance, the amount by which the leading end of the recording medium  130  projects from the opening at the left side  145  is automatically set by a control circuit, not illustrated, and the recording medium  130  is moved accordingly. 
     With this configuration, the recording medium  130  can be taken out from the left side  145  of the image forming apparatus  10  with ease. 
     According to the present embodiment, the recording medium  130  is moved in the second sheet discharge direction  134  by the first sheet discharge roller  137 . Furthermore, the recording medium  130  is moved in the third-sheet discharge direction  144  by the plurality of the second sheet discharge rollers  143 . Therefore, with the combination of the first sheet discharge roller  137  and the second sheet discharge rollers  144 , the recording medium  130  or a stack of recording media sheets can be rotated on the sheet receiver  50 . 
     In other words, when the first sheet discharge roller  137  is rotated in the frontal direction and the second sheet discharge rollers  143  are turned to the left, the recording medium  130  turns in a clockwise direction, thereby causing the right front corner portion of the recording medium  130  to project farthest from the sheet discharge portion  112 . 
     The rotation of the first sheet discharge roller  137  and the second sheet discharge rollers  143  are set to stop when the recording medium  130  projects from the sheet discharge portion  112  so that the user can easily pick up the right front corner portion of the recording medium  130  from the sheet discharge portion  112 . 
     By contrast, when the first sheet discharge roller  137  is rotated in the frontal direction and the second sheet discharge rollers  143  are rotated to the right, the recording medium  130  rotates in a counterclockwise direction, thereby causing the left front corner portion of the recording medium  130  to project farthest from the sheet discharge portion  112 . 
     The rotation of the first sheet discharge roller  137  and the second sheet discharge rollers  143  are set to stop when the recording medium  130  projects from the sheet discharge portion  112 , so that the user can easily pick up the left front corner portion of the recording medium  130  from the sheet discharge portion  112 . 
     There may be a case in which, upon rotation of the recording medium  130 , the corner portion of the recording medium  130  may interfere with a wall of the sheet discharge portion  112 . In such a case, the recording medium  130  can be moved in the second sheet discharge direction  134  as well as the third sheet discharge direction  144  in advance so as not to interfere with the wall of the sheet discharge portion  112 , and then the recording medium  130  can be rotated from that position. 
     Furthermore, alternatively, when the sheet discharge tray  140  is mounted on the first sheet discharge roller  137  and the second sheet discharge rollers  143 , the recording medium  130  is placed on a planar surface. Accordingly, the recording medium  130  can be smoothly transported in the second sheet discharge direction  134 , the third sheet discharge direction  144 , or a rotation direction  146  that is a composite of the second and the third discharge directions. 
     Alternatively, the notch  142  illustrated in  FIG. 9  can be provided to the sheet discharge tray  141  at a position allowing the user to easily pick up the recording medium  130  when the recording medium  130  is turned in the rotation direction  146 . 
     According to the present embodiment, the first sheet discharge roller  137  and the plurality of the second sheet discharge rollers  143  move directly the recording medium  130  or the sheet discharge tray  141 . Alternatively, however, a belt member can be employed instead of the roller, or a combination of both can be employed. 
     It is to be noted that, unless otherwise stated, each component according to the present embodiment is the same and has the same function as that of the foregoing embodiments 1, 5, and 6. 
     A detailed description of a driving mechanism for moving the recording medium is omitted herein. However, known mechanical devices can be employed for the driving mechanism moving in a single direction or different directions achieved by combining the directions. Therefore, those skilled in the art will readily recognize the driving mechanism for moving the recording medium. 
     According to the illustrative embodiments, the present invention is applied to the copier as an example of an image forming apparatus in which the recording medium is internally discharged. However, as long as an image forming apparatus is equipped with a sheet discharge portion in which the recording medium is moved, the present invention is also applicable. 
     The recording medium  130  can be transported substantially to the front side of the image forming apparatus  10  so that the user is able to see and easily pick up the recording medium  130 . 
     The endless sheet transport belt  131 , the sheet discharge roller  137  (the first sheet discharge roller), and the push member  138  are employed as the devices for moving the recording medium  130 . With this configuration, the recording medium  130  can be moved with a relatively simple configuration 
     The sloped surface  139  allows the recording medium  130  to move to the front side due to gravity, thereby not necessitating any power, thus achieving cost reduction. 
     The sheet discharge tray  140  is movably mounted on the sheet receiver  50  and moves itself to the front side so that a plurality of the recording media sheets stacked thereon are not disorganized as the recording media sheets are discharged. 
     The sheet discharge tray  141  includes the notch  142 , thereby facilitating the user to pick up the recording medium  130  from the internal sheet discharge portion  112 . 
     With the combination of the sheet discharge devices that move in different moving directions, the recording medium  130  can be moved in a direction most desirable for the user. 
     Furthermore, it is to be understood that elements and/or features of different illustrative embodiments may be combined with each other and/or substituted for each other within the scope of this disclosure and appended claims. In addition, the number of constituent elements, locations, shapes and so forth of the constituent elements are not limited to any of the structure for performing the methodology illustrated in the drawings. 
     Still further, any one of the above-described and other exemplary features of the present invention may be embodied in the form of an apparatus, method, or system. 
     For example, any of the aforementioned methods may be embodied in the form of a system or device, including, but not limited to, any of the structure for performing the methodology illustrated in the drawings. 
     Example embodiments being thus described, it will be obvious that the same may be varied in many ways. Such exemplary variations are not to be regarded as a departure from the scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.