JP2005025211A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which includes an image reading part for reading a document image, an operation part disposed at the front of the image reading part, and an image forming part for forming recorded images onto a recording sheet, ejects a recording sheet after recording into a paper ejection space between the image reading part and the image forming part, and enables the recording sheet to be taken out from an opening defined at the front of the paper ejection space and openings defined on sides of the paper ejection space, the image forming apparatus preventing image distortion due to downward warp of the operation part and the image reading part. <P>SOLUTION: The front edge 7E of a main body casing portion 7D which is located above the paper ejection space 6, is located distant in the direction toward the back of a main body casing 7 from the front external face 7F of a main body casing portion which is located below the paper ejection space 6. This improves visibility of a recording sheet P ejected in the paper ejection space 6. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention includes an operation unit, an image reading unit that reads a document image, and an image forming unit that forms a recording image on a recording sheet, the operation unit is located on the front side of the image reading unit, and The image forming unit is located below the image reading unit, and a paper discharge space in which a recording sheet on which a recording image is formed is discharged between the image reading unit and the image forming unit. The paper discharge space relates to an image forming apparatus in which at least one of the one end side and the other end side in the main body casing width direction and the front portion of the paper discharge space are open.

  For example, an image forming apparatus of the above type configured as a copying machine, a printing machine, a printer, a facsimile machine, or a multifunction machine having at least two of these functions is conventionally known. This type of image forming apparatus is also referred to as an in-body discharge type image forming apparatus. According to such an image forming apparatus, the recording sheet on which the recording image is formed in the image forming unit is discharged into the paper discharge space between the image reading unit and the image forming unit. Compared to an image forming apparatus that discharges a recording sheet onto a protruding sheet discharge tray, it is possible to reduce the size of the structure and the installation space. Since the front part of the paper discharge space is open, the recording sheet discharged to the paper discharge space can be easily taken out from the opening of the front part. Further, in this type of image forming apparatus, since the operation unit is located on the front side of the image reading unit and the operation unit is located near the operator, the operator can easily operate the operation unit. .

  By the way, in the in-body discharge type image forming apparatus described at the beginning, at least one of one end side and the other end side in the body casing width direction of the discharge space and the front portion of the discharge space are opened. Therefore, the portion supporting the image reading unit and the operation unit is reduced, and the image reading unit and the operation unit are easily bent downward by their own weight. In addition, when the operator operates the operation unit located at the front of the image reading unit, the operator places a finger on the operation unit and applies a downward load to the operation unit. The part bends downward. This bending includes bending only when the operation unit and the image reading unit are pressed down and bending due to permanent deformation over time. In either case, the image reading unit is greatly bent downward. As a result, the original image cannot be read correctly, and the image on the recording sheet formed in the image forming section is distorted, and a normal recorded image cannot be reproduced. Such image distortion is particularly noticeable in the case of a full-color image.

  As described above, the image forming apparatus of the format described at the beginning can improve the size, ease of taking out the recording sheet, and operability with respect to the operation unit. There is a problem in that the portion is easily bent downward.

  The present invention has been made on the basis of the above-described recognition, and an object of the present invention is to form an image in the form described at the beginning that can prevent the image reading unit and the operation unit from largely bending downward with a simple configuration. To provide an apparatus.

  In order to achieve the above object, according to the present invention, in the image forming apparatus of the type described at the beginning, a front end portion of a main body housing portion positioned above the paper discharge space is positioned below the paper discharge space. An image forming apparatus is proposed in which the position is shifted from the front outer surface of the main body housing portion to the rear side of the main body housing.

  In this case, it is advantageous that the front end portion is arranged at a position shifted by at least 30 mm from the front outer surface to the rear side of the main body housing.

  3. The image forming apparatus according to claim 1 or 2, wherein the front end portion is arranged so that a vertical line passing through the front end portion can intersect a maximum size recording sheet discharged into the paper discharge space. It is advantageous if the position is shifted to the rear side of the main body housing with respect to the outer surface of the part (claim 3).

  Furthermore, in the image forming apparatus according to any one of claims 1 to 3, the image reading unit and the operation unit are provided only on a main body housing portion on one end side in the main body housing width direction and a main body housing portion on the rear side. The paper discharge space can be configured to be opened in a state where the front portion thereof communicates with the other end in the width direction of the main body casing.

  The image forming apparatus according to any one of claims 1 to 3, wherein the image reading unit and the operation unit are supported with respect to the image forming unit only by a main body housing portion on a rear side. (Claim 5).

  The image forming apparatus according to claim 4, wherein the recording sheet is configured to be discharged from a main body casing portion on one end side in a main body casing width direction to a discharge space, and from the front outer surface to the main body. The front end is located at the front and rear positions within a range between a position 55 mm away from the rear side of the casing and a center in the width direction orthogonal to the conveyance direction of the recording sheet discharged into the discharge space. It is advantageous if the position is shifted to the rear side (Claim 6).

  The image forming apparatus according to claim 4 or 6, wherein the recording sheet is configured to be discharged from a main body casing portion on one end side in the main body casing width direction to a discharge space. A relay unit for transporting the recording sheet discharged into the discharge space to a finisher disposed adjacent to the image forming apparatus main body is detachably attached to the bottom of the relay unit. It is advantageous if the mounting surface of the recording sheet discharged into the paper discharge space above the upper wall surface is configured.

  Furthermore, in the image forming apparatus according to claim 4, 6 or 7, a front outer wall surface of the main body casing portion on one end side in the main body casing width direction is positioned on the front side of the main body casing with respect to the front end portion. It is advantageous if they are arranged so as to be offset (claim 8).

  Further, in the image forming apparatus according to any one of claims 1 to 8, the center of gravity of the total weight of both the image reading unit and the operation unit is such that the image reading unit and the operation unit in the front-rear direction of the main body housing. It is advantageous if it is located on the rear side with respect to the center position of the both (claim 9).

  Furthermore, in the image forming apparatus according to any one of claims 1 to 9, an automatic document feeder is mounted on the image reading unit, and the center of gravity of the automatic document feeder is automatically set in the front-rear direction of the main body casing. It is advantageous if it is located on the rear side of the center position of the document feeder.

  Further, in the image forming apparatus according to any one of claims 1 to 10, it is advantageous that the image forming unit is configured to form a full-color image on a recording sheet (claim 11).

  According to the present invention, it is possible to effectively suppress a problem that the image reading unit and the operation unit are bent downward, and to improve the visibility of the recording sheet discharged into the paper discharge space.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a perspective view of an image forming apparatus according to the present embodiment as viewed obliquely from the front. The image forming apparatus shown here includes an image forming apparatus main body 1, a finisher 2 connected adjacent to the side, And an automatic document feeder 3 mounted on the upper part of the image forming apparatus main body 1. FIG. 2 is a cross-sectional view of the image forming apparatus main body 1. The finisher 2 and the automatic document feeder 3 are devices that are mounted as options according to user requests.

  FIG. 3 is a schematic explanatory diagram when the image forming apparatus main body 1 is viewed from the left side of FIG. 2 with the automatic document feeder 3 and the finisher 2 removed. As shown in FIG. 3, when the operator OP operating the image forming apparatus faces the image forming apparatus main body 1 in a normal posture, the side facing the operator OP is the image forming apparatus main body 1 or the main body casing 7. The front F is the rear side opposite to the image forming apparatus main body 1 or the rear portion R of the main body casing 7. The direction orthogonal to the front-rear direction, that is, the left and right direction of the operator facing the image forming apparatus main body 1 is the width direction W (FIGS. 1 and 2) of the image forming apparatus main body 1 or the main body casing 7 thereof.

  The image forming apparatus of this example is configured as a multifunction machine having functions of a copying machine, a printer, and a facsimile. The image forming apparatus body 1 includes an operation unit 16 and an image reading unit 4 that reads a document image as will be described later. And an image forming unit 5 for forming a recorded image on the recording sheet. The operation unit 16 is located on the front side, that is, the front side of the image reading unit 4, and the operation unit 16 and the main body housing portion of the image reading unit 4 are integrally connected. The image forming unit 5 is located below the image reading unit 4 and the operation unit 16. As is known per se, the operation unit 16 is provided with various keys such as a print start key, a mode switching key, a numeric keypad, and the operator can operate the image forming apparatus by pressing a predetermined key. Further, a paper discharge space 6 in which a recording sheet on which a recording image is formed is discharged by the image forming unit 5 is defined between the operation unit 16 and the image reading unit 4 and the image forming unit 5. Has been. A paper feed unit 8 that sends out the recording sheet P to the image forming unit 5 is disposed below the image forming apparatus main body 1.

  The finisher 2 and the automatic document feeder 3 are mounted according to the user's request as described above. Therefore, the image forming apparatus may be configured by the image forming apparatus main body 1 alone. Further, at least a part of the paper feeding unit 8 can be configured as a paper feeding unit separate from the image forming apparatus main body.

  As can be seen from FIGS. 1 and 3, the paper discharge space 6 is opened in a state where the front portion and the left side portion thereof communicate with each other, and an operator inserts a hand into the paper discharge space 6 through the opening. be able to. The “communication state” means that there is no column or the like at the boundary between the front part and the left part in the open part of the paper discharge space 6 in the example of FIG. 1, and the open part is continuous. It means that it is an open part. Further, as will be described later with reference to FIGS. 5 and 6, the right portion of the paper discharge space 6 can be opened. In this way, the paper discharge space is opened in a state where at least one of the one end side and the other end side in the main body casing width direction and the front portion of the paper discharge space communicate with each other.

  As shown in FIG. 2, the image reading unit 4 of this example includes a light source 9, first to third mirrors 10, 11, and 12, an imaging lens 13, and a CCD 14 that is an example of a photoelectric conversion element. These elements are arranged inside the main body housing portion of the image reading unit 4, and the contact glass 15 is fixed to the upper part thereof. When the print start key of the operation unit 16 is pressed, the document set on the document table 17 of the automatic document feeder 3 is automatically fed onto the contact glass 15 and placed thereon. A document placed on the contact glass 15 is indicated by a symbol D in FIG.

  On the other hand, the light source 9 and the first mirror 10, and the second and third mirrors 11 and 12 move to the right in FIG. 2, and the original D is illuminated by the light from the light source 9, and the reflected light is reflected from the first to the first. Reflected by the three mirrors 10, 11, and 12, passes through the imaging lens 13 and reaches the CCD 14. In this way, the original image is formed on the CCD 14 and subjected to photoelectric conversion. As described above, the image reading unit 4 of the image forming apparatus of the present example includes the optical system that forms an image of a document and the photoelectric conversion element that forms the image of the document. The image is read. The document D for which the image has been read is automatically conveyed to the paper discharge unit 18 of the automatic document feeder 3. When the automatic document feeder 3 is not provided, a pressure plate for pressing the document placed on the contact glass 15 is provided.

  On the other hand, the image forming unit 5 shown as an example in the figure includes a belt-shaped photoconductor 19 which is an example of an image carrier and various elements described below. These elements are included in the image forming unit 5. It is arranged inside the main body casing. The schematic configuration of the image forming unit 5 is as follows.

  The photoreceptor 19 is wound around a plurality of rollers and rotated in the direction of arrow A, and the endless belt-shaped intermediate transfer body 20 that is also wound around the plurality of rollers is contacted with the photoreceptor 19 in the direction of arrow B. Driven by rotation. When the photoconductor 19 rotates, the surface of the photoconductor is charged to a predetermined polarity by a charger 21 disposed on the photoconductor 19. On the other hand, as described above, the laser light L that is light-modulated in accordance with the image information read by the image reading unit 4 is emitted from the laser writing unit 22, and the surface of the photosensitive member charged with the laser light L is exposed. Thereby, an electrostatic latent image is formed on the photosensitive member.

  Further, a yellow developing unit 23Y, a magenta developing unit 23M, a cyan developing unit 23C, and a black developing unit 2BK are provided facing the photoconductor 19, and these developing units include yellow toner, magenta toner, cyan toner, and black toner. Each is housed. Each of the developing units 23Y to 23BK is supported by a driving device (not shown) so as to occupy a developing position approaching the outer peripheral surface of the photoconductor 19 and a retracted position separated from the outer peripheral surface. The aforementioned electrostatic latent image is visualized as a yellow toner image by the first developing unit that occupies the developing position, in this example, the yellow developing unit 23Y. At this time, the other developing units 23M to 23BK occupy the retracted position. The yellow toner image formed on the photosensitive member 19 is primarily transferred onto the intermediate transfer member 20 by the action of the primary transfer roller 23 disposed on the back side of the intermediate transfer member 20, and after the toner image is transferred, the yellow toner image on the photosensitive member 19 is transferred. Transfer residual toner adhering to the outer peripheral surface is removed by the cleaning device 24.

  Next, in the same manner as described above, a second electrostatic latent image is formed on the outer peripheral surface of the photoconductor 19, and this is visualized as a magenta toner image by the magenta developing device 23M that has occupied the development position. The toner image is transferred onto the surface of the intermediate transfer body 20 from above the yellow toner image. The surface of the photoreceptor after the toner image transfer is cleaned by a cleaning device 24. In exactly the same manner, a cyan toner image and a black toner image are sequentially formed on the outer peripheral surface of the photosensitive member 19 by the cyan developing unit 23C and the black developing unit 23BK, and these toner images are formed on the surface of the intermediate transfer member 20 in advance. The toner image transferred onto the toner image is transferred onto the toner image.

  On the other hand, the sheet feeding cassettes 124, 124A, 124B, 124C of the sheet feeding unit 8 respectively store recording sheets P made of, for example, transfer paper or resin sheets, and the uppermost recording sheet in any one of the sheet feeding cassettes. When the recording sheet is fed in the direction of arrow C and passes between the intermediate transfer member 20 and the secondary transfer roller 25, the superimposed toner image on the intermediate transfer member 20 is transferred to the recording sheet P in a lump. The The transfer residual toner adhering to the surface of the intermediate transfer member after the toner image is transferred is removed by the cleaning device 26.

  As described above, the image forming unit 5 is used to form a recording image composed of a toner image on the recording sheet P, and includes at least an image carrier on which the toner image is formed. The The recording sheet P on which the recording image is formed is further conveyed upward and passes through the fixing device 27. At this time, the toner image on the recording sheet is fixed to the recording sheet by the action of heat and pressure. The recording sheet P on which the recording image is formed in this manner is discharged into the paper discharge space 6.

  Although the outline of the configuration of the image forming apparatus has been described together with the operation when the image forming apparatus functions as a copying machine, the image forming apparatus can be used as a facsimile or a printer. Since it is clear from a technique known per se, the description thereof is omitted.

  Here, the configuration for processing the recording sheet P discharged into the discharge space 6 can be selected as appropriate, but the image forming apparatus of this example is configured as follows.

  As shown in FIGS. 1 and 2, a relay unit 28 is detachably attached to the bottom of the paper discharge space 6, and a paper discharge tray 29 is fixedly disposed in a paper discharge space portion above the relay unit 28. A main body housing portion 7A is located on the side of the paper discharge space 6, and a first switching claw 30 for switching the path of the recording sheet P that has exited the fixing device 27 is swingable inside the main body housing portion 7A. It is supported by. When the first switching claw 30 occupies the position shown in FIG. 2, the recording sheet is guided upward by the first switching claw 30 and conveyed upward as indicated by an arrow G. The paper is discharged onto the paper discharge tray 29 as shown by the arrow G1 by the first paper discharge roller pair 31 disposed in 7A and stacked there.

  When the first switching claw 30 is switched, the recording sheet P that has exited the fixing device 27 is guided by the first switching claw 30 and conveyed to the left as indicated by an arrow H in FIG. And is fed into the cover 32 of the relay unit 28. A second switching claw 33 is swingably supported in the cover 32, and when the second switching claw 33 occupies the position shown in FIG. 2, the recording sheet P is guided to the second switching claw 33. Then, the sheet is conveyed in the direction of the arrow H1 and is discharged onto the upper wall surface 35 of the cover 32 and placed thereon as indicated by the arrow H2 by the second sheet discharge roller pair 34 disposed in the cover 32. The upper wall surface 35 constitutes the placement surface of the recording sheet discharged into the paper discharge space above it.

  As described above, in the image forming apparatus of this example, the recording sheet P can be selectively discharged to one of the two paper discharge units in the paper discharge space 6. For example, when the image forming apparatus functions as a facsimile, the recording sheet P is discharged onto the discharge tray 29, and when the image forming apparatus functions as a copying machine, the recording sheet is transferred onto the relay unit 28. When the image is discharged onto the wall surface 35, the operability of the image forming apparatus is improved. The recording sheet P discharged into the paper discharge space 6 in this way can be taken out from the front opening or the side opening.

  On the other hand, when the second switching claw 33 is switched and the recording sheet is conveyed in the direction indicated by the arrow H3, the recording sheet is disposed in the lower space of the upper wall of the relay unit 28 and supported by the cover 32. The paper is transported by a plurality of transport roller pairs 36, discharged from the paper discharge space 6 through the opening on the side of the paper discharge space 6, and sent to the finisher 2 described above. The finisher 2 is configured, for example, as a stapler that binds a bundle of recording sheets, a punching machine that punches holes in the recording sheets, or a collating machine that collates recording sheets. Receive post-processing.

  As described above, in the image forming apparatus of this example, the recording sheet is discharged from the main body casing portion 7A on one end side in the width direction of the main body casing 7 (right end side in the example of FIG. 2) to the discharge space 6. Further, the paper discharge space 6 is also opened at the other end in the width direction of the main body housing 7 (the left end side in the example of FIG. 2). A relay unit 28 for transporting the recording sheet P discharged into the space 6 to the finisher 2 disposed adjacent to the image forming apparatus main body 1 is detachably attached. The upper wall surface 35 of the relay unit 28 constitutes a placement surface for the recording sheet P discharged into the paper discharge space 6 above the upper wall surface 35.

  As described above, when the relay unit 28 is provided at the bottom of the paper discharge space 6, the recording sheet P that has exited the fixing device 27 can be transported to the finisher 2 at the shortest distance until the recording sheet is transported to the finisher 2. Can be shortened. As shown by a chain line arrow I in FIG. 2, the recording sheet exiting the fixing device is conveyed through the upper part of the image reading unit and sent to the finisher, or as shown by a chain line arrow J in FIG. After the recording sheet exiting the fixing device is discharged out of the main body of the image forming apparatus, the recording sheet is turned upside down by a reversing device (not shown), and then conveyed to a finisher (not shown). Although devices are also known, these devices inevitably suffer from the disadvantage that the transport path from the fixing device to the finisher becomes long and the time required for the transport becomes long. If the illustrated relay unit 28 is used, such a drawback can be avoided.

  The relay unit 28 including the conveyance roller pair 36, the second switching claw 33, the cover 32 that supports these, and the like is used only in the image forming apparatus to which the finisher 2 is connected, and the image without the finisher 2 is used. The relay unit 28 is not attached to the forming apparatus. In this case, the recording sheet conveyed in the direction of arrow H is discharged onto the bottom surface 38 of the paper discharge space 6 by the paper discharge roller pair 37.

  As described above, since the relay unit 28 is attached only when the finisher 2 is connected, the relay unit 28 is configured to be detachably attached to the bottom of the paper discharge space 6.

  At that time, in the image forming apparatus of this example, the image reading unit 4 and the operation unit 16 are formed by only the main body housing portion 7A on one end side in the width direction of the main body housing 7 and the main body housing portion 7B on the rear side. The relay unit is supported by the image unit 5 and is opened in a state where the front portion thereof communicates with the other end side in the body casing width direction (left end side in the example of FIG. 2). When 28 is attached to the bottom of the paper discharge space 6, the attachment work can be performed very easily and can be easily removed.

  As shown in FIG. 4, the relay unit 28 can be integrated with the main body casing 7 so that the unit 28 cannot be attached and detached. However, in this case, the image forming apparatus of the user that does not require a finisher can be used. Since the relay unit 28 remains attached, there is an inevitable disadvantage that the paper discharge space 6 is narrowed accordingly. Such disadvantages can also be avoided in the image forming apparatus shown in FIGS.

  In each of the image forming apparatuses described above, the recording sheet can be discharged into the paper discharge space 6 between the image reading unit 4 and the image forming unit 5 and the recording sheet can be taken out from the opening of the paper discharge space 6. The installation space for the image forming apparatus main body can be reduced.

  By the way, as described above, in this type of conventional image forming apparatus, the front portion and the side portion of the paper discharge space 6 are opened in communication with each other, and the operation portion is provided at the front portion of the image reading portion 4. 16 is provided, and its overall weight is large, so that the operation unit 16 and the image reading unit 4 are easily bent downward. In addition, since the operation unit 16 can be loaded downward by the operator, the deflection of the image reading unit 4 and the operation unit 16 becomes more remarkable. In order to prevent such bending, the image reading unit 4 and the operation unit 16 may be configured to be robust, and the support structure may be made particularly strong. However, this increases the cost of the image forming apparatus. I can't escape my shortcomings.

  Therefore, in the image forming apparatus of this example, as shown in FIGS. 1, 3, and 4, the front end portion 7 </ b> E of the main body housing portion 7 </ b> D positioned above the paper discharge space 6 is more Also, the position is shifted by δ on the rear side of the main body casing from the front outer surface 7F of the main body casing portion positioned below. In the illustrated example, the front end portion 7E of the main body casing portion of the operation unit 16 is disposed with a position shifted rearward from the front outer surface 7F of the front door 40 constituting the main body casing portion.

  According to the above configuration, the distance that the operation unit 16 and the image reading unit 4 protrude forward from the main body housing part 7B on the rear side is reduced, so that the operation unit 16 and the image reading unit 4 act on the main body housing portion. The bending moment to be reduced can be reduced, and it is possible to prevent the operation unit 16 and the image reading unit 4 from being greatly bent downward without particularly strongly supporting the operation unit and the image reading unit. Thereby, it is possible to prevent the image on the recording sheet formed by the image forming unit 5 from being distorted and to improve the image quality.

  Further, this type of conventional image forming apparatus has a drawback that it is difficult to visually check the recording sheet discharged into the discharge space when the operator is standing, and it is difficult to take out the recording sheet. That is, since the paper discharge space is located below the image reading unit and the operation unit, the recording sheet discharged to the paper discharge space is blocked by the image reading unit and the operation unit, and in an attitude where the operator is standing, The recording sheet in the paper discharge space is difficult to see and has a drawback that it is difficult to take out the recording sheet. Such a problem can be solved to some extent in the conventional image forming apparatus by increasing the overall height of the image forming apparatus main body and making the position of the paper discharge space closer to the eyes of the operator. If the overall height is increased, the operability of the image forming apparatus is deteriorated, so there is a limit to increasing the height of the image forming apparatus main body. In particular, in the case of a color image forming apparatus that forms a full-color image in the image forming unit, the number of component parts of the image forming unit increases, so that the height of the image forming unit increases. Since the overall height of the sheet cannot be increased so much from the viewpoint of operability, the width in the height direction of the sheet discharge space must be narrowed, thereby increasing the visibility of the recording sheet in the sheet discharge space and taking it out. The operability was degraded.

  On the other hand, in the image forming apparatus shown in FIGS. 1 to 4, the front end portion 7 </ b> E of the main body housing portion 7 </ b> D located above the paper discharge space 6 is positioned below the paper discharge space 6. Since the position is shifted by δ from the front outer surface 7F of the casing portion to the rear side of the main body casing, as can be seen from FIG. 3, when the operator OP faces the image forming apparatus main body 1, the operator OP Even when standing, the recording sheet P discharged into the paper discharge space 6 can be visually confirmed and can be easily taken out. In order to further enhance the visibility of the recording sheet P placed on the upper wall surface 35 of the relay unit 28 or the bottom surface 38 when the unit 28 is not provided, a notch 41 (FIG. 1) is formed on the front side of the paper discharge tray 29. It is also advantageous to form

  The amount δ of shifting the front end portion 7E toward the rear side can be set as appropriate. However, as a result of many experiments, the front end portion 7E is disposed at a position shifted by at least 30 mm toward the rear side of the main body housing from the front outer surface 7F. It has been confirmed that the above effects can be ensured.

  Further, as shown in FIG. 3, the front end portion 7E is more than the outer surface 7F so that the vertical line V passing through the front end portion 7E can intersect the maximum size recording sheet P discharged into the paper discharge space 6. When the recording sheet P is arranged at a position shifted to the rear side of the main body housing, the maximum size recording sheet P usable in the image forming apparatus can be viewed from directly above, and the visibility can be further enhanced. Even when a recording sheet of the minimum size that can be used in the image forming apparatus is discharged into the discharge space 6, the shift amount δ may be set so that the vertical line V intersects the recording sheet of the minimum size. it can. In this way, all size recording sheets discharged into the discharge space 6 can be viewed from directly above, and the visibility can be particularly improved. Setting it large is not easy. Setting the shift amount δ so that the vertical line V intersects the maximum size recording sheet discharged into the paper discharge space 6, for example, an A3 size recording sheet, can be realized without any particular difficulty.

  In the image forming apparatus shown in FIGS. 5 and 6, the image reading unit 4 and the operation unit 16 are supported with respect to the image forming unit 5 only by the main body housing portion 7B on the rear side, and the example of FIG. In FIG. 6, the recording sheet is discharged from the main body housing portion 7B on the rear side to the paper discharge space 6 as indicated by an arrow K. In the example of FIG. The body part is configured to be discharged into the paper discharge space 6 as indicated by an arrow K1. Such an image forming apparatus can also employ the above-described configurations.

  The image forming apparatus of the type shown in FIGS. 5 and 6 can check the recording sheet discharged into the discharge space 6 from three sides and take it out. However, the main body housing that supports the image reading unit 4 The number of parts is further smaller than that of the image forming apparatus shown in FIGS. 1 and 2, and the image reading unit 4 is easily bent downward. For this reason, the structure which shifts the front-end part 7E to back side rather than the front part outer surface 7F can be employ | adopted especially advantageously.

  In the image forming apparatus shown in FIGS. 1 to 4, as described above, the recording sheet P is discharged from the main body casing portion 7 </ b> A on one end side in the width direction of the main body casing 7 to the discharge space 6. In this case, the position CL is 55 mm from the front outer surface 7F to the rear side of the main body housing, and the center CL (in the width direction orthogonal to the conveyance direction of the recording sheet P discharged into the paper discharge space 6). When the front end portion 7E is arranged at a position before and after the range between FIG. 3) and the rear side of the main body housing, the visibility of the recording sheet P is particularly improved, and the removal thereof is more effective. Experiments have also confirmed that the bending moment generated in the image reading unit 4 can be effectively reduced.

  Further, in the image forming apparatus shown in FIGS. 1 to 4, the main body casing in which the front outer wall surface 7 </ b> G of the main body casing portion 7 </ b> A on one end side in the main body casing width direction is located above the paper discharge space 6. The position is shifted from the front end portion 7E of the portion to the front side of the main body casing. If the main body housing portion 7A is configured such that the front outer wall surface 7G of the main body housing portion 7A projects forward as described above, the portion 7A can be enlarged, and the rigidity of the main body housing portion 7A can be increased. Can be increased. Since the image reading unit 4 and the operation unit 16 are supported on the main body casing portion 7A having increased rigidity as described above, these can be firmly supported and the support stability thereof can be increased. Thereby, the malfunction which the image reading part 4 and an operation part bend below can be suppressed much more effectively.

  FIG. 7 is a schematic side view of the image forming apparatus shown in FIGS. 5 and 6. As shown in this figure, the center of gravity of the total weight of both the image reading unit 4 and the operation unit 16 is If it is configured to be positioned rearward of the center position CL1 of both the image reading unit 4 and the operation unit 16 in the front-rear direction of the main body housing 7, the operation unit 16 and the image reading unit 4 are particularly strongly supported. Even if not, the bending of the operation unit 16 and the image reading unit 4 when a downward load is applied to the operation unit 16 can be reduced or substantially eliminated. Such a configuration can also be applied to the image forming apparatus shown in FIGS.

  Similarly, as illustrated in FIG. 7, when the automatic document feeder 3 is mounted on the image reading unit 4, the automatic document feeder 3 has a center of gravity in the front-rear direction of the main body housing 7. Even if it is configured so as to be located rearward of the center position CL2 of 3, the same effect as described above can be obtained. For example, a heavy element such as a motor or a substrate (not shown) of the automatic document feeder 3 is arranged in a portion 3A on the back side of the device 3, and the center of gravity of the automatic document feeder 3 is located on the rear side. What is necessary is just to comprise so that it may be located. Such a configuration can also be applied to the image forming apparatus shown in FIGS.

  In the conventional image forming apparatus in which the automatic document feeder 3 is mounted on the image reading unit 4, the total weight of these and the operation unit is particularly large. For example, even when the automatic document feeder 3 is opened and closed, Although there is a possibility that the operation unit and the image reading unit are largely bent downward, such a drawback can be avoided by adopting the above-described configurations.

  Further, in the case of a color image forming apparatus in which the image forming unit 5 is configured to form a full color image on the recording sheet P, the width in the height direction of the paper discharge space 6 becomes narrow, and the full color image can be distorted. Since this is particularly conspicuous, the present invention can be applied particularly advantageously to a color image forming apparatus. However, it is obvious that the present invention can be widely applied to an image forming apparatus that forms a monochrome image.

  Further, an example of an image forming apparatus provided with an image forming unit having at least an image carrier has been described. For example, a master is wound around a plate cylinder, ink is supplied to the master, and a recording sheet is brought into contact with the master for recording. The present invention can be widely applied to an image forming apparatus having a printing type image forming unit that forms a recorded image on a sheet, an ink jet type image forming unit, and the like.

1 is an external perspective view of an image forming apparatus. 2 is a vertical sectional view of the image forming apparatus main body. FIG. FIG. 3 is a schematic side view of the image forming apparatus main body viewed from the left side of FIG. 2 with the finisher and the automatic document feeder removed. It is a perspective view which shows the other example of an image forming apparatus. FIG. 10 is a perspective view illustrating still another example of the image forming apparatus. It is a perspective view which shows another example of an image forming apparatus. FIG. 4 is a diagram for explaining the gravity center positions of an image reading unit and an automatic document feeder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Finisher 3 Automatic document feeder 4 Image reading part 5 Image forming part 6 Paper discharge space 7 Main body housing 7A Main body housing part 7B Main body housing part 7D Main body housing part 7E Front end 7F Front outer surface 7G Front outer wall surface 16 Operation unit 28 Relay unit 35 Upper wall surface CL center CL1 center position CL2 center position P Recording sheet V Vertical line W Width direction

Claims (11)

An operation unit; an image reading unit that reads a document image; and an image forming unit that forms a recorded image on a recording sheet; the operation unit is located in front of the image reading unit; and A paper discharge space that is positioned below the image reading unit and from which the recording sheet on which the recording image is formed is discharged is defined between the image reading unit and the image forming unit. In the image forming apparatus in which the paper discharge space is opened in a state where at least one of the one end side and the other end side in the body housing width direction and the front part of the paper discharge space communicate with each other.
The front end portion of the main body housing portion located above the paper discharge space is shifted from the front outer surface of the main body housing portion located below the paper discharge space on the rear side of the main body housing. An image forming apparatus. The image forming apparatus according to claim 1, wherein the front end portion is disposed at a position shifted by at least 30 mm toward the rear side of the main body housing from the front outer surface. The front end is arranged at a position rearward of the main body housing from the front outer surface so that a vertical line passing through the front end can intersect the maximum size recording sheet discharged into the paper discharge space. The image forming apparatus according to claim 1 or 2. The image reading unit and the operation unit are supported with respect to the image forming unit only by a main body housing portion on one end side in the main body housing width direction and a main body housing portion on the rear side. 4. The image forming apparatus according to claim 1, wherein the image forming apparatus is opened in a state where the other end in the width direction of the main body casing communicates. The image forming apparatus according to claim 1, wherein the image reading unit and the operation unit are supported with respect to the image forming unit only by a main body housing portion on a rear side. The recording sheet is configured to be discharged into a paper discharge space from a main body casing portion on one end side in the width direction of the main body casing, and is disposed at a position 55 mm away from the front outer surface to the rear side of the main body casing. 5. The front end of the recording sheet discharged into the space is shifted to the rear side of the main body housing at a front and rear position within a range between the center in the width direction orthogonal to the conveyance direction of the recording sheet. The image forming apparatus described in 1. The recording sheet is configured to be discharged from a main body casing portion at one end in the width direction of the main body casing to a discharge space, and a recording sheet discharged into the discharge space is placed at the bottom of the discharge space. A relay unit that transports to a finisher disposed adjacent to the image forming apparatus main body is detachably attached, and the upper wall surface of the relay unit is loaded with a recording sheet discharged into a paper discharge space above the upper wall surface. The image forming apparatus according to claim 4 or 6, constituting a mounting surface. 8. The image according to claim 4, 6 or 7, wherein a front outer wall surface of a main body casing portion at one end side in the main body casing width direction is arranged with a position shifted to the front side of the main body casing from the front end portion. Forming equipment. The center of gravity of the total weight of both the image reading unit and the operation unit is located on the rear side of the center position of both the image reading unit and the operation unit in the front-rear direction of the main body housing. The image forming apparatus according to any one of the above. An automatic document feeder is mounted on the image reading unit, and the center of gravity of the automatic document feeder is located behind the center position of the automatic document feeder in the front-rear direction of the main body housing. The image forming apparatus according to claim 9. The image forming apparatus according to claim 1, wherein the image forming unit is configured to form a full-color image on a recording sheet.

Images