Image forming apparatus

Abstract

To provide an image forming apparatus that can support sheets long in a conveying direction and each formed an image, while suppressing an increase in a space for installing the image forming apparatus.SOLUTION: There is provided an image forming apparatus in which sheets each discharged by a discharge part and formed with an image by image forming means, are stacked on a first stacking part that overlaps the image forming means and an image scanning part and that is arranged below the image scanning part in the horizontal direction. The image forming apparatus comprises a support unit detachably attached to an image forming part and supported by the image forming part without being supported by a floor surface and supporting the sheets together with the first stacking part downstream of the first stacking part in a sheet discharging direction.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus for forming an image on a sheet. [Background technology]

[0002] In an image forming apparatus, a sheet on which an image is formed is discharged to the outside of the apparatus by a discharge roller. In recent years, there has been a demand for compatibility with sheets that are long in the conveying direction (hereinafter, long sheets) as one of the adaptability features for a wide variety of sheets. Therefore, it has been considered to provide a stacking device capable of stacking long sheets (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-111257 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, since a support surface that is long in the horizontal direction is required to support the long sheet discharged after the image is formed thereon, the space required for installing the image forming apparatus becomes large. [Means for solving the problem]

[0005] The image forming apparatus of the present invention is characterized by having an image forming section having an image forming means therein that forms an image on a sheet, an image reading section provided above the image forming section and capable of reading an image of a document, a first discharge section that discharges sheets on which an image has been formed by the image forming means, a first stacking section that overlaps the image forming means and the image reading section in the horizontal direction and is located below the image reading section and on which sheets discharged by the first discharge section are stacked, and a support unit that is detachably attached to the image forming section, is supported by the image forming section without being supported on a floor surface, and supports sheets together with the first stacking section downstream in the sheet discharge direction from the first stacking section. Effect of the Invention

[0006] The present invention can provide an image forming apparatus capable of supporting a discharged long sheet while suppressing an increase in the space required for installing the image forming apparatus. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a cross-sectional view of the image forming apparatus according to the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of the image forming apparatus according to the present invention. [Diagram 3] 11 is a diagram showing a state in which long sheets are stacked and sheets are being discharged to a second stacking section in the embodiment according to the present invention. FIG. [Figure 4] FIG. 13 is a perspective view for explaining a configuration for attaching an expansion tray unit. [Diagram 5] FIG. 13 is a cross-sectional view illustrating a configuration for attaching an expansion tray unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] FIG. 1 is a cross-sectional view of an image forming apparatus 100 including an image reading unit 900 capable of reading an image of an original document, and a printer section 901 that forms the image of the original document read by the image reading unit 900 on a sheet.

[0009] An image reading unit 900 as an image reading section includes a document glass 910 as a placement table on which a document is placed, and a reading sensor 911 that reads an image of the document placed on the document glass 910 .

[0010] The printer unit 901 as an image forming unit includes a housing 441, and is provided with an image forming means 442 that forms an image on a sheet inside the housing 441. As will be described in detail later, the image forming means 442 of the printer unit 901 in this embodiment is of an intermediate transfer tandem type in which image forming units of four colors are arranged side by side on an intermediate transfer belt.

[0011] A sheet feed cassette 403 for storing sheets is disposed below the printer unit 901. In the printer unit 901, the sheets S are stored in the sheet feed cassette 403 in a manner that they are stacked on a sheet feed tray that is lifted up, and are fed by the feed unit 110 in accordance with the image formation timing of the image forming apparatus.

[0012] A manual feed tray 401 is rotatably supported on a housing 441 of a printer unit 901. Sheets stacked on the manual feed tray 401 are fed by a manual feed unit 402.

[0013] The sheet S fed by the feeding unit 110 or the manual feeding unit 402 passes through a transport path and is transported to the skew correction device 120. After skew correction and timing correction are performed in the skew correction device 120, the sheet S is sent to the secondary transfer unit 130 so that an image is formed by an image forming unit.

[0014] The image forming means 442 contained in the housing 441 of the printer section 901 includes an image forming unit 140, an intermediate transfer belt 145, a secondary transfer section 130, and a fixing device 150. The image forming unit 140 includes a photoconductor 141, an exposure device 142, a developing device 143, and a primary transfer device 144. The secondary transfer section 130 is a toner image transfer nip portion for the sheet S formed by a secondary transfer inner roller 131 and a secondary transfer outer roller 132 that are substantially opposed to each other, and transfers a toner image onto the sheet S by applying a predetermined pressure force and an electrostatic load bias.

[0015] The process of forming an image sent to the secondary transfer portion 130 at the same timing as the process of conveying the sheet S to the secondary transfer portion 130 described above will be described.

[0016] In the image forming unit 140, the exposure device 142 emits light based on the signal of the image information sent to the photoconductor 141, the surface of which has been uniformly charged by the charging means, and a latent image is formed through a diffraction means or the like as appropriate. The electrostatic latent image thus formed on the photoconductor 141 is developed by the developer 143 to form a toner image on the photoconductor 141. Thereafter, a predetermined pressure force and an electrostatic load bias are applied by the primary transfer device 144, and the toner image is transferred onto the intermediate transfer belt 145. In the case of FIG. 1, four sets of the image forming units 140 described above, yellow Y, magenta M, cyan C, and black Bk, are provided side by side in the left-right direction 801 of the image forming apparatus 100.

[0017] Next, the intermediate transfer belt 145 will be described. The intermediate transfer belt 145 is driven to be transported in the direction of the arrow A in FIG. 1. Therefore, the above-mentioned Y, M, C, and Bk image forming devices process the images in parallel. The image forming process for each color is performed at a timing when the image is superimposed on the upstream toner image that has been primarily transferred onto the intermediate transfer belt 145. As a result, a full-color toner image is finally formed on the intermediate transfer belt 145 and transported to the secondary transfer unit 130.

[0018] Through the above-described conveying process of the sheet S and the image forming process, a full-color toner image is secondarily transferred onto the sheet S in the secondary transfer section 130.

[0019] After the image is transferred, the sheet S is transported to a fixing device 150. The fixing device 150 applies a predetermined pressure by rollers or belts that are substantially opposed to each other, and generally applies a heating effect by a heat source such as a heater, thereby melting and fixing the toner on the sheet S.

[0020] The sheet S on which the image has been fixed by the fixing device 150 is discharged onto a first stacking section 170 by a first discharge roller 160 serving as a first discharge section, or is branched off by a first switching flapper 151 and conveyed toward a second discharge roller 161 located above the first stacking section 170. The sheet S conveyed to the second discharge roller 161 serving as a second discharge section is discharged onto the second stacking section 171.

[0021] In the case of double-sided printing, after the rear end of the sheet S passes the second switching flapper 152, the sheet is conveyed to the double-sided conveying path 180 by the reversing operation of the second discharge roller 161. After passing through the double-sided conveying path 180, the sheet S is again subjected to skew correction and timing correction by the skew correction device 120, and is then sent to the secondary transfer unit 130 where the image on the second side is transferred and fixed by the fixing device 150. The sheet is then discharged onto the first stacking unit 170 or the second stacking unit 171.

[0022] The first stacking section 170 includes a first stacking surface 170a on which sheets are stacked, and a second stacking surface 170b on which sheets are stacked, which is disposed downstream of the first stacking surface 170a in the discharge direction. The first stacking surface 170a is inclined with respect to the horizontal direction so as to be upward as it approaches the downstream in the discharge direction. The inclination of the second stacking surface 170b with respect to the horizontal direction is smaller than the inclination of the first stacking surface 170a with respect to the horizontal direction.

[0023] The second stacking section 171 includes a third stacking surface 171a on which sheets are stacked, and a fourth stacking surface 171b on which sheets are stacked, which is disposed downstream of the third stacking surface 171a in the discharge direction. The third stacking surface 171a is inclined with respect to the horizontal direction so as to be upward as it approaches the downstream in the discharge direction. The inclination of the fourth stacking surface 171b with respect to the horizontal direction is smaller than the inclination of the third stacking surface 171a with respect to the horizontal direction.

[0024] In this way, the first stacking section 170 and the second stacking section 171 have a slope that rises from the upstream to the downstream in the discharge direction of the sheets S. Therefore, the discharged sheets S can be aligned on the upstream side in the discharge direction by the weight of the sheets S themselves.

[0025] The first stacking section 170 and the second stacking section 171 on which the sheets on which images are formed are stacked are disposed in an internal space 192 below the image reading unit 900. The internal space 192 is a space below the image reading unit 900 between one side and the other side of the housing 441 of the printer section 901 in the left-right direction 801. The internal space 192 includes a first stacking area 190 for the sheets stacked on the first stacking section 170 and a second stacking area 191 for the sheets stacked on the first stacking section 170. The first stacking section 170 and the second stacking section 171 of the internal space 192 overlap with the image reading unit 900, at least a part of the image forming means (for example, the intermediate transfer belt 145), and the paper feed cassette 403 in the left-right direction 801. The first stacking section 170 and the second stacking section 171 are provided between the image reading unit 900 and at least a part of the image forming means (for example, the intermediate transfer belt 145) in the vertical direction 802.

[0026] 2 is a cross-sectional view of the image forming apparatus 100 when an expansion tray unit 200 that expands the tray surface of the first stacking unit 170 is attached to a position facing the side surface of the printer unit 901. The expansion tray unit 200 is detachably attached to the image forming apparatus 100.

[0027] The expansion tray unit 200 as a support unit that supports a sheet has a main body mounting portion 202 and an expansion tray 201 as a support tray that supports a sheet. The expansion tray 201 is rotatable with respect to the main body mounting portion 202. An upper surface 202a of the main body mounting portion 202 and a loading surface 201a of the expansion tray 201 serve as support surfaces that support the sheet discharged by the first discharge roller 160. The height of an upstream end 422 of the support surface of the expansion tray unit 200 in the discharge direction is set to be lower than the height of a downstream end 421 of the first stacking portion 170.

[0028] The main body mounting section 202 is disposed at a position facing one side surface 501 in the left-right direction 801 of the printer section 901. As will be described in detail later, the expansion tray unit 200 including the main body mounting section 202 is supported by a portion of the housing 441 of the printer section 901 that the main body mounting section 202 faces.

[0029] The main body mounting section 202 includes a protruding portion 461. When the expansion tray unit 200 is mounted on the image forming apparatus 100, the protruding portion 461 is located between a side surface 501 of the printer section 901 and the first stacking section 170 in the left-right direction 801. When the expansion tray unit 200 is mounted on the image forming apparatus 100, the protruding portion 461 overlaps with the first stacking section 170 in the up-down direction 802.

[0030] A storage unit 600 having an upper open storage space for storing paper documents and the like is disposed on the side of the main body mounting unit 202 opposite to the surface facing the side surface 501 of the printer unit 901. In the storage unit 600, for example, a manual for the image forming apparatus 100 is inserted from above into the storage space and stored therein.

[0031] As described above, the extension tray unit 200 is detachable from the image forming apparatus 100 so that the main body mounting section 202 faces the side surface 501 of the printer section 901. The extension tray unit 200 extends the loading surface of the first stacking section 170. The loading surface 201a of the extension tray 201 is inclined so that it becomes higher toward the downstream side in the discharge direction from the horizontal. Since the extension tray 201 and the first stacking section 170 are inclined, the long sheet 210 returns to the discharge direction by its own weight. Therefore, the discharged long sheet 210 can be aligned upstream in the discharge direction by the weight of the long sheet 210 itself.

[0032] At least a part of the extension tray 201 is at a different position from the second stacking section 171 in the left-right direction 801 and overlaps with the second stacking section 171 in the height direction. The upper end of the extension tray 201 is located above the highest point of the second stacking section 171. With this arrangement, the position of the upper end of the extension tray 201 can be made higher, that is, the inclination of the extension tray 201 with respect to the horizontal can be made larger while keeping the height of the internal space 192 small. In this embodiment, the inclination of the loading surface 201a of the extension tray 201 with respect to the horizontal is larger than the inclination of the first loading surface 170a of the first loading section 170 with respect to the horizontal. If the inclination angle of the loading surface 201a of the extension tray 201 with respect to the horizontal direction is large, the alignment on the upstream side of the discharge direction due to the weight of the sheets loaded on the extension tray 201 is improved. In this embodiment, the upper end of the extension tray 201 is located above the lower surface of the image reading unit 900.

[0033] 3 is a diagram showing a state in which the long sheets 210 are stacked and further sheets are stacked in the second stacking section 171. As shown in FIG. 3, the stacking surface 201a of the expansion tray 201 and the upper surface 202a of the main body mounting section 202 support the downstream portion of the long sheets 210, the upstream portion of which is supported by the first stacking section 170.

[0034] In this embodiment, the same sheets are supported by the first stacking section 170 and the expansion tray 201 in the internal space 192. Here, an image forming apparatus in which a stacking device that stacks sheets without using the internal space 192 is installed on the side of the image forming apparatus 100 is taken as a comparative apparatus. Compared to the width in the left-right direction 801 of this comparative apparatus, in this embodiment, it is possible to reduce the space for installing the image forming apparatus 100 by the length in the left-right direction 801 of the internal space 192.

[0035] In this embodiment, long sheets 210 can be loaded while allowing the sheets to be discharged into the internal space 192. Therefore, in a state in which sheets are loaded on the second stacking section 171 as shown in Fig. 3, long sheets 210 can be further loaded into the first stacking area 190. This makes it possible to load (support) long sheets while maintaining the inherent advantages of the image forming apparatus 100 in terms of loading capacity in the internal space 192 and installation space.

[0036] In an image forming apparatus for an office where space saving is required, it is difficult to install a dedicated device for stacking sheets (long sheets) that are long in the conveying direction side by side on the side of the image forming apparatus main body. When stacking long sheets, it is possible to install a post-processing device supported on the floor surface on the side of the image forming apparatus main body, discharge the sheets from the upper discharge outlet of the two discharge parts of the apparatus main body, and stack them using the upper surface of the post-processing device. In this case, a problem is that it becomes impossible to stack other sheets in the internal space. In other words, since it is necessary to separately install an intermediate conveying unit in the internal space to convey the sheets to the post-processing device, it becomes impossible to stack sheets other than the long sheets in the internal space. Therefore, it is necessary to discharge the sheets from the discharge outlet of the post-processing device. Since a stacking tray is also installed at the discharge outlet of the post-processing device, the installation space also becomes large. In contrast, in this embodiment, it is possible to load another long sheet 210 while still being able to discharge the sheets into the internal space 192.

[0037] Next, a configuration for mounting the expansion tray unit 200 to the image forming apparatus 100 will be described with reference to Figures 4 and 5. Figure 4 is a perspective view of the expansion tray unit 200 as seen from inside the image forming apparatus 100. Figure 5 is a cross-sectional view showing a configuration for engaging the expansion tray unit 200 with the image forming apparatus 100.

[0038] In Fig. 4, reference numeral 502 denotes a side surface portion that is a part of the housing 441 and extends in the up-down direction 802 and that includes a side surface 501 (see Figs. 2 and 3) of the printer unit 901. In Fig. 4, illustration of members of the image forming apparatus 100 other than the side surface portion 502 is omitted. Two engagement holes 301 are provided in the side surface portion 502, arranged side by side in the front-rear direction 803. The front-rear direction 803 is a direction perpendicular to the left-right direction 801 and perpendicular to the up-down direction 802.

[0039] Two engagement claws 302 are provided on the main body mounting portion 202 of the expansion tray 201. The engagement claws 302, which are hooking claws, extend downward as shown in FIG.

[0040] FIG. 5 is a partial cross-sectional view for illustrating a state in which an engagement claw 302 serving as a claw portion is engaged with an engagement hole 301. As shown in FIG.

[0041] The main body mounting section 202 can be mounted on the image forming apparatus 100 by engaging the engaging claws 302 with the engaging holes 301. The engaging claws 302 as engaging parts inserted into the engaging holes 301 as engaged parts are hooked on the side surface 502, so that the expansion tray unit 200 is supported by the side surface 502 without being supported on the floor surface. That is, two engaging claws 302 are inserted into each of the two engaging holes 301. The engaging claws 302 inserted into the inside of the printer section 901 through the engaging holes 301 contact an inner surface 504 of the side surface 502 opposite to the side surface (exterior surface) 501, as shown in FIG. 5. Then, the moment centered on the engaging claws 302 due to the weight of the expansion tray unit 200 is received by the abutting portion 303, which is a convex portion arranged below the engaging claws 302, contacting the side surface 501 of the side surface 502. The engaging claw 302 may also be made to abut against the lower edge of the engaging hole 301 so that the edge of the engaging hole 301 also supports the engaging claw 302 .

[0042] When the expansion tray unit 200 is attached to the printer section 901, the engagement claws 302 and the engagement holes 301 are arranged so as to be covered by the expansion tray unit 200 and cannot be seen.

[0043] The housing of the main body mounting section 202 of the expansion tray unit 200 includes a first side section 323 facing the printer section 901 and a second side section 322 opposite to the first side section 323. A removable cover member 321 is disposed on the second side section 322. When the cover member 321 is removed, the first side section 323 can be accessed through the inside of the expansion tray unit 200. The first side section 323 is fastened (fixed) to the side section 502 by a screw as a fastening member through an opening created by removing the cover member 321. At this time, the screw is inserted into the screw hole 451 (see FIG. 4). In other words, the expansion tray unit 200 is configured so that the fastening point of the screw can be accessed through the opening created by removing the cover member 321. As shown in FIG. 4, the fastening point of the screw is between two engagement claws in the front-rear direction 803, and is approximately the center of the expansion tray unit 200 in the front-rear direction 803. Therefore, the expansion tray unit 200 can be stably fixed.

[0044] The present invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the present invention.

[0045] In the above embodiment, the extension tray unit 200 is provided with the engagement claw 302, which is hooked into the engagement hole 301 in the side surface portion 502 to support the extension tray unit 200 on the side surface portion 502. However, the embodiment for supporting the extension tray unit 200 by a member on the side surface of the printer section 901 is not limited to this. For example, the side surface portion 502 may be provided with a protrusion such as a claw, and the extension tray unit 200 may be hooked and supported by the protrusion. In this case, for example, the extension tray unit 200 may be configured so that the protrusion engages with a hole or groove in the extension tray unit 200.

[0046] The functions and effects of this embodiment will be described below. (1) The extension tray unit 200 can be detachably attached, so that it is possible to support long sheets on which images are formed. Here, the extension tray unit 200 supports the sheets together with the first stacking section 170 provided in the internal space 192, so that it is possible to support long sheets while preventing the occupied area of ​​the image forming apparatus from becoming large. (2) The expansion tray unit 200 is supported by the housing 441 of the printer section 901, without being supported on the floor surface. Therefore, the compact expansion tray unit 200 can be configured to be supported inexpensively without requiring any dedicated equipment for supporting the expansion tray unit 200. (3) The expansion tray unit 200 is attached to the printer unit 901 by inserting and hooking the engagement hooks 302 of the expansion tray unit 200 into the engagement holes 301 in the side surface portion 502 of the housing 441 of the printer unit 901. Therefore, the installation work is easy. (4) The engagement claws 302 and the engagement holes 301 are arranged so as not to be visible by being covered by the expansion tray unit 200. In this embodiment, there is less risk of the expansion tray unit 200 being accidentally removed, compared to a case in which the engagement portion for connecting the expansion tray unit 200 and the printer section 901 is visible. (5) The extension tray 201 of the extension tray unit 200 is located above the second stacking portion 171 in the internal space 192. Therefore, it is possible to realize stable stacking of long sheets while suppressing the height of the internal space 192. In particular, with this arrangement, in this embodiment, the inclination angle of the stacking surface 201a of the extension tray 201 with respect to the horizontal direction can be made large. Therefore, the movement of the sheets stacked on the extension tray 201 toward the upstream side in the discharge direction due to their own weight is easily promoted, so that stable stacking of long sheets is possible. (6) The height of the upstream end 422 of the support surface of the expansion tray unit 200 in the discharge direction is lower than the height of the downstream end 421 of the first stacking section 170. Therefore, the leading edge of the sheet discharged by the first discharge roller 160 does not get caught on the expansion tray unit 200, and the sheet is discharged smoothly. (7) The first side portion 323 is fastened to the side portion 502 with a screw through an opening in the housing of the expansion tray unit 200 created by removing the cover member 321. This stably attaches the expansion tray unit 200. Furthermore, the screws used for fastening can be made invisible by attaching the cover member 321. The fastening location of the screw is between the two engagement claws in the front-rear direction 803 so that the expansion tray unit 200 can be stably fixed with the screw, and is approximately the center of the expansion tray unit 200 in the front-rear direction 803. The opening in the housing that allows access to such a fastening location for stable fixation can be blocked using the cover member 321. [Explanation of symbols]

[0047] 100 Image forming device 900 Image reading unit 901 Printer section 160 first discharge roller, 161 Second discharge roller 170 First loading section, 171 Second Loading Section 192 Interior space 200 Expansion Tray Unit

Claims

1. an image forming unit including an image forming means for forming an image on a sheet; an image reading unit provided above the image forming unit and capable of reading an image of a document; a first discharge section that discharges a sheet on which an image is formed by the image forming means; a first stacking section that overlaps the image forming means and the image reading section in a horizontal direction and is disposed below the image reading section, and on which the sheets discharged by the first discharge section are stacked; An image forming apparatus characterized by having a support unit that is removably attached to the image forming section, the support unit being supported by the image forming section without being supported on a floor surface, and supporting sheets together with the first stacking section downstream in the sheet discharge direction from the first stacking section.

2. the support unit is attached to a position facing a housing of the image forming unit, 2. The image forming apparatus according to claim 1, wherein the support unit is supported by a portion of a housing of the image forming section that faces the support unit.

3. the support unit is attached to a position facing a side surface of a housing of the image forming unit, 2. The image forming apparatus according to claim 1, wherein the support unit includes an engaging portion that engages with an engaged portion provided on a member having the side surface of a housing of the image forming portion.

4. 4. The image forming apparatus according to claim 3, wherein the supporting unit is supported by the housing by the engaging portion being hooked onto the engaged portion.

5. 5. The image forming apparatus according to claim 4, wherein the engaging portion is disposed at a position where the engaging portion is covered by the supporting unit and cannot be seen when the supporting unit is attached to the image forming portion.

6. the support unit is attached to a position facing a side surface of a housing of the image forming unit, a hole provided in one of the support unit and a member having the side surface of a housing of the image forming unit; a claw portion provided on the other of the support unit and a member having the side surface of a housing of the image forming unit, 2. The image forming apparatus according to claim 1, wherein the support unit is supported by the image forming section via the claw portion inserted into the hole.

7. The support unit has a claw portion, the image forming unit has a hole into which the claw portion is inserted on a side surface facing the support unit, 2. The image forming apparatus according to claim 1, wherein the support unit is attached to the image forming section by engaging the claw portion with the hole.

8. 5. The image forming apparatus according to claim 4, wherein the support unit is fastened to a housing of the image forming section by a fastening member.

9. a detachable cover member is disposed on a side of a housing of the support unit opposite to a side facing the image forming unit, 9. The image forming apparatus according to claim 8, wherein the fastening points of the fastening members can be accessed through an opening in the housing that is created by removing the cover member.

10. a second discharge section located above the first discharge section and configured to discharge a sheet on which an image is formed by the image forming unit; 2. The image forming apparatus according to claim 1, further comprising: a second stacking section that overlaps the image forming means and the image reading section in the horizontal direction, and is positioned below the image reading section and above the first stacking section, and on which sheets discharged by the second discharge section are stacked.

11. the support unit includes a support tray that is inclined upward toward the downstream side and supports the sheet, 11. The image forming apparatus according to claim 10, wherein the highest point of the support tray is located downstream of the second stacking portion in the discharge direction and above the second stacking portion.

12. An image forming apparatus as described in claim 1, characterized in that the height of the upstream end of the support surface of the support unit in the discharge direction is lower than the height of the downstream end of the first stacking section, and the height of the downstream end of the support surface of the support unit is higher than the height of the downstream end of the first stacking section.

Images