JP6445864B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus including a housing that houses an image forming unit.

  In the image forming apparatus, the housing in which the image forming unit is accommodated has a structure in which pillars are erected at the four corners of a rectangular bottom plate, and front and rear and left and right side plates are arranged between the pillars to form a rectangular parallelepiped shape. Things are common. In such a case, rigidity is obtained by firmly fixing each column and each side plate to the bottom plate. On the other hand, with the demand for lighter image forming apparatuses, the weight of housings has also been reduced.

  One of the measures for reducing the weight of the housing is to reduce the weight of the bottom plate. However, when the weight of the bottom plate is reduced, there is a concern about a decrease in rigidity of the entire housing.

  Patent Document 1 discloses an image forming apparatus including a casing having a base frame and a main body frame provided on the base frame, and the base frame connects four square pipes in a grid pattern. Configured. Further, in Patent Document 2, a pair of support columns having a U-shaped concave cross section is erected on the bottom plate so that the U-shaped openings face each other, and the front plate is supported by both support columns. An image forming apparatus configured to increase rigidity is disclosed.

JP 2004-4367 A JP 2009-265540 A

  The image forming apparatus described in Patent Document 1 uses, as a bottom plate, a base frame in which square pipes are connected in a cross-beam shape instead of a plate-like member. The overall weight cannot be reduced. In addition, there is a possibility that the connection strength between the base frame formed of the square pipe and the support cannot be sufficiently obtained, and the rigidity of the support cannot be secured. In the image forming apparatus described in Patent Document 2, the image forming unit of the image forming unit and the paper feed cassette are positioned on the front side plate, but the conveying device is configured to be positioned on the support column. There is a possibility that the image forming unit and the conveying device are not accurately positioned due to the tolerance.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide an image forming apparatus including a casing that has high rigidity and can be reduced in weight.

  In order to solve the above problems, an image forming apparatus according to the present invention is an image forming apparatus including a housing having a rectangular parallelepiped hollow portion in which an image forming portion is accommodated, and the housing includes four corners of the hollow portion. Each of the four support columns, four surrounding members respectively disposed on four sides of the hollow portion, and a rectangular partition plate that divides the hollow portion into an upper space and a lower space. The partition plate is fastened to at least one of the four struts and is fastened to at least one of the four surrounding members.

  By adopting such a configuration, it is possible to increase the rigidity of the housing, so that it is possible to delete the bottom plate of the housing that has been provided in the past or to reduce the weight of the bottom plate, and to reduce the weight of the entire image forming apparatus. it can.

  In the image forming apparatus of the present invention, the four surrounding members include a front side plate, a rear side plate, a left side plate, and a right side plate, and the front side plate, the rear side plate, the left side plate, and the right side plate are The four corners of the hollow portion may be fastened to the support column.

  By adopting such a configuration, the rigidity of the support can be increased and the rigidity of the entire casing can be increased.

  In the image forming apparatus according to the aspect of the invention, the image forming unit is stored in the upper space, and a paper feed cassette that stores a sheet on which an image is formed in the image forming unit is stored in the lower space. A conveyance frame that forms a conveyance path of the sheet from a cassette to the image forming unit, the conveyance frame also serving as either the left side plate or the right side plate, and the front side plate and the It may be characterized by being fastened to the rear plate.

  By adopting such a configuration, it is possible to reduce the number of parts and to reduce the weight and cost.

  In the image forming apparatus according to the aspect of the invention, the image forming unit includes a transport device that transports the sheet along the transport path, an image forming device that forms an image on the sheet transported by the transport device, and the image forming device. A fixing device that fixes an image formed by an image device to the sheet, and a positioning portion for the conveying device, the image forming device, and the fixing device is formed on the front side plate and the rear side plate. It is good also as a feature.

  By adopting such a configuration, the cumulative tolerance can be reduced, so that each apparatus can be positioned with high accuracy and high-quality image formation can be performed.

  In the image forming apparatus according to the aspect of the invention, the partition plate, the left side plate, and the right side plate may be formed in a U shape having an opening at the bottom when viewed from the front of the lower space. .

  By adopting such a configuration, when an impact is applied to the bottom of the casing, the impact is distributed to each support column, so that the entire casing can be reduced in impact.

  In the image forming apparatus according to the aspect of the invention, the rear side plate, the left side plate, and the right side plate may be formed in a U shape with an opening at the front when viewed from above the lower space. .

  By adopting such a configuration, the load in the vertical direction can be distributed between the rear side plate and the left and right side plates, and the strength of the housing can be increased.

  According to the present invention, since the bottom plate of the housing can be deleted while maintaining high rigidity, the weight of the image forming apparatus can be reduced.

1 is a schematic diagram illustrating an outline of a color printer according to an embodiment of the present invention. 1 is a perspective view showing an overall structure of a housing in a color printer according to an embodiment of the present invention. In the color printer which concerns on one Embodiment of this invention, it is a perspective view which shows the partition plate and left side plate of a housing | casing. In the color printer which concerns on one Embodiment of this invention, it is a perspective view which shows the rear side board of a housing | casing. FIG. 4 is a perspective view illustrating a conveyance frame of a housing in the color printer according to the embodiment of the invention.

  Hereinafter, an image forming apparatus according to an embodiment of the present disclosure will be described with reference to the drawings.

  First, the overall main configuration of the color printer 1 (image forming apparatus) will be described with reference to FIG. FIG. 1 is a schematic diagram showing an outline of a printer according to an embodiment of the present invention. Hereinafter, the front side in FIG. 1 is the front side (front side) of the color printer 1, and the left and right directions will be described with reference to the direction viewed from the front of the printer 1.

  The color printer 1 includes a housing 3 having a substantially rectangular parallelepiped hollow portion 2. A paper discharge tray 5 is provided on the upper surface of the housing 3. A paper feed cassette 6 is provided at the lower part of the hollow portion 2. Above the paper feed cassette 6, an exposure device 7 constituted by a laser scanning unit (LSU) and an intermediate between the rollers are installed. A transfer roller 10 that forms a secondary transfer portion 9 between the transfer belt 8 and the intermediate transfer belt 8; and four image forming devices 11 that are arranged in parallel along the lower portion of the intermediate transfer belt 8. A process unit 12 including the sheet feeding unit 6, a conveyance device 13 that conveys the sheet fed from the sheet feeding cassette 6 to the process unit 12, and a toner container 14 that contains four color toners are housed.

  The image forming device 11 is rotatably provided with a photosensitive drum 15 as an image carrier. Around the photosensitive drum 15, a charging device 16, a developing device 17, a transfer roller 18, and a cleaning device are provided. The device 19 and the charge removal device 20 are sequentially arranged along the rotation direction of the photosensitive drum 15.

  Further, a fixing device 21 is accommodated in the hollow portion 2 above the secondary transfer portion 9. Further, a paper discharge device 22 facing the paper discharge tray 5 is provided above the fixing device 21.

  Further, on the right side of the process unit 12, a paper conveyance path 23 is provided from the conveyance device 13 to the paper discharge device 22 through the secondary transfer unit 9 and the fixing device 21.

  An image forming operation of the printer 1 having such a configuration will be described. In each image forming device 11, after the surface of the photosensitive drum 15 is charged by the charging device 16, an electrostatic latent image is formed on the surface of the photosensitive drum 15 by the laser light from the exposure device 7 (see arrow P). The The electrostatic latent image is developed into a corresponding color toner image by the developing device 17 using toner supplied from the toner container 14. This toner image is primarily transferred onto the surface of the intermediate transfer belt 8 by the transfer roller 18. Each image forming device 11 sequentially repeats the above operation, whereby a full-color toner image is formed on the intermediate transfer belt 8. The toner and charge remaining on the photosensitive drum 15 are removed by the cleaning device 19 and the charge removal device 20.

  On the other hand, the paper fed from the paper feed cassette 6 is temporarily stopped by the transport device 13 and then transported to the secondary transfer unit 9 in synchronism with the image forming operation described above. 2, the full-color toner image on the intermediate transfer belt 8 is secondarily transferred to the paper. The sheet on which the toner image is secondarily transferred is conveyed downstream in the conveyance path 23 and enters the fixing device 21, where the toner image is fixed on the sheet. The paper on which the toner image is fixed is discharged from the paper discharge device 22 onto the paper discharge tray 5.

  Each image forming device 11, the conveying device 13, and the fixing device 21 are formed with positioning pins (not shown) for positioning with respect to the housing 3.

  Next, the housing 3 will be described with reference to FIGS. 2 is a perspective view of the entire housing viewed from the right front, FIG. 3 is a perspective view of the housing viewed from the left front, FIG. 4 is a perspective view of the housing viewed from the right front, and FIG. It is the perspective view seen from the left rear.

  As shown in FIG. 2, the housing 3 includes support columns 31, 32, 33, and 34 disposed at four corners (front left corner, front right corner, rear left corner, rear right corner) of the hollow portion 2, and the hollow portion 2. Is divided into a lower space 2a and an upper space 2b, a rectangular partition plate 35, a front plate 36 (a surrounding member) disposed on the front surface of the hollow portion 2, and a rear plate 37 disposed on the rear surface of the hollow portion 2. (A surrounding member), a left side plate 38 (a surrounding member) disposed on the left surface of the hollow portion 2, and a transport frame 39 (a surrounding member) disposed on the right surface of the hollow portion. The periphery of the front side plate 36, the rear side plate 37, the left side plate 38, and the transport frame 39 is covered with an exterior cover (not shown).

  The four support columns 31, 32, 33, and 34 are angle-shaped members having a substantially L-shaped cross section or channel-shaped members having a U-shaped cross section, and are rounded at a predetermined pitch in the vertical direction. The holes are formed side by side. The front right column 32, the rear left column 33, and the rear right column 34 are formed longer than the front left column 31 and extend above the hollow portion 2.

  As shown in FIG. 3, the partition plate 35 includes a horizontally long rectangular base portion 41 and a step portion 42 that rises stepwise from the right edge of the base portion 41. A plurality of reinforcing recesses 43 are formed in the base portion 41 along the diagonal or outer periphery by pressing. The partition plate 35 is made of, for example, a sheet metal material.

  The partition plate 35 is arranged with a space between the right side surface of the hollow portion 2, and the front left corner and the rear left corner are screwed at substantially the center in the vertical direction of the front left column 31 and the rear left column 33, respectively. It is concluded with.

  As shown in FIG. 4, the front side plate 36 has a horizontally long rectangular shape, and a substantially rectangular opening 45 is formed at the center. A rectangular front mounting plate 47 is fastened with screws at the right end of the upper edge of the front plate 36. The front side plate 36 and the front mounting plate 47 are made of, for example, a sheet metal material. The front plate 36 is disposed on the front side surface of the upper space 2b, and is fastened to the front left column 31 and the front right column 32 with screws, and is also fastened to the front surface of the partition plate 35 with screws. The front mounting plate 47 is fastened to the front right column 32 with screws.

  As shown in FIGS. 2 and 5, the rear side plate 37 has a rectangular shape, and a rectangular rear mounting plate 48 corresponding to the front mounting plate 47 of the front side plate 36 at the right end of the upper edge. Are fastened with screws. The rear side plate 37 and the rear mounting plate 48 are made of, for example, a sheet metal material. The rear side plate 37 is disposed over the entire rear side surface of the upper and lower spaces 2b, 2a, and is fastened to the rear left column 33 and the rear right column 34 with screws, and is also fastened to the rear surface of the partition plate 35 with screws. Yes. The rear mounting plate 48 is fastened to the rear right column 34 with screws.

  The front side plate 36 and the rear side plate 37 are formed with positioning holes into which positioning pins formed in the image forming devices 11 and the transport device 13 are inserted. The front mounting plate 47 and the rear mounting plate 48 are formed with positioning holes into which positioning pins formed on the fixing device 21 are inserted. Further, between the front side plate 36 and the rear side plate 37, a vertical frame 49 extending in the vertical direction is installed above the right end portion of the step portion 42 of the partition plate 35, as shown in FIG. .

  As shown in FIG. 3, the left side plate 38 has a left upper side plate 51 and a lower left side plate 52, and is made of, for example, a sheet metal material. The upper left plate 51 has a horizontally long rectangular shape, is disposed in the upper half of the left side surface of the upper space 2b, and is fastened to the front left column 31 and the rear left column 33 with screws. The lower left side plate 52 has a horizontally long rectangular shape, and a lower edge portion 52a bent rightward is formed at the lower end. The lower left side plate 52 is disposed over the entire left side surface of the lower space 2a, and is fastened to the front left column 31 and the rear left column 33 with screws, and is also fastened to the left side surface of the partition plate 35 with screws. .

  The conveyance frame 39 is a member that forms a conveyance path 23 from the sheet cassette 6 to the secondary transfer unit 9 for the sheet fed. As shown in FIG. 3, FIG. 4, and FIG. 5, the transport frame 39 has a shape like an L-shape when viewed from the front, and has an upper frame portion 54 that extends substantially horizontally and a right edge of the upper frame portion 54. And a right frame portion 55 bent downward, for example, made of sheet metal material or resin. The upper frame portion 54 is formed with lattice-like ribs on the upper surface. An opening 55 a through which a sheet fed from the sheet feeding cassette 6 passes is formed at the lower portion of the right frame portion 55. A conveyance roller 55b is provided above the opening 55a, and a registration roller 55c is provided above the conveyance roller 55b.

  The upper frame portion 54 is disposed below the step portion 42 of the partition plate 35, the right frame portion 55 is disposed so as to be slightly inside the right side surface of the lower space 2a, and the upper frame portion 54 is disposed on the front side plate. 36 and the rear side plate 37 are fastened with screws (screw fastening locations are indicated by P1 in FIG. 4 and P2 in FIG. 5), and the right frame portion 55 is fastened to the front right column 32 and the rear right column 34 with screws. It is concluded.

  As shown in FIG. 2, the housing 3 further includes a channel-shaped front stay 61 that is installed between the lower ends of the front left column 31 and the front right column 32. The front stay 61 is fastened to the lower edge portion 52a of the lower left side plate 52 of the left side plate 38 with screws.

  Further, an upper plate 63 is installed between the front mounting plate 47 and the rear mounting plate 48. Further, two upper and lower stays 65 are installed between the rear left column 33 and the rear right column 34. A left frame 66 that extends forward is provided at the upper end of the rear left column 33. An image reading unit is supported on the left frame 66.

  In the housing 3 having the above-described configuration, the paper feed cassette 6 is accommodated in the lower space 2a below the partition plate 35, and the process unit 12 and each toner are stored in the upper space 2b above the base portion 41 of the partition plate 35. The container 14 is accommodated, and the partition plate 35 prevents the developer scattered from the process unit 12 from dropping onto the sheet accommodated in the paper feed cassette 6. Each image forming device 11 included in the process unit 12 is attached to and detached from the opening 45 formed in the front side plate 36, and the positioning pins are inserted into the positioning holes formed in the front and rear side plates 36 and 37, thereby 37 is positioned.

  Further, the transport device 13 is disposed between the upper frame portion 54 of the transport frame 39 and the step portion 42 of the partition plate 35. The conveying device 13 is positioned with respect to the front and rear side plates 36 and 37 by inserting positioning pins into positioning holes formed in the front and rear side plates 36 and 37. Further, the fixing device 21 and the paper discharge device 22 are arranged in a space between the front and rear mounting plates 47 and 48 and the upper plate 63. The fixing device 21 is positioned with respect to the front and rear side plates 36 and 37 to which the front and rear mounting plates 47 and 48 are fastened by inserting positioning pins into positioning holes formed in the front and rear mounting plates 47 and 48.

  The bottom surface of the housing 3 forms a rectangular opening 71 surrounded by the front stay 61, the lower edge of the rear side plate 37, the lower edge of the transport frame 39, and the lower edge portion 52 a of the left side plate 38. ing. That is, the conventional bottom plate is not provided, and the lower surface of the paper feed cassette 6 accommodated in the lower space 2 a is exposed from the opening 71.

  The partition plate 35 is fastened to the front left column 31 and the rear left column 33 with screws at the front left corner and the rear left corner, and is fastened to the front plate 36, the rear plate 37, and the lower left plate 52 with screws. Yes. A paper feed frame 39 is fastened to the front right column 32 and the rear right column 34 and the front and rear side plates 36 and 37 between the partition plate 35 and the right side surface of the hollow portion 2. Thus, the lower left side plate 52, the partition plate 35 connected via the front and rear side plates 36, 37, the upper frame portion 54 of the paper feed frame 39, and the right frame portion 55 of the paper feed frame 39 are in the lower space 2a. When viewed from the front side, it is formed in a U-shape with the bottom opened. Furthermore, the rear side plate 37, the lower left side plate 52, and the right frame portion 55 of the transport frame 39 are formed in a U-shape with the front opening when viewed from the upper side of the lower space 2a.

  As described above, in the image forming apparatus 1 of the present invention, there is no bottom plate that is conventionally formed of a sheet metal material, so that the weight of the housing 3 can be reduced. When such a bottom plate is not provided, there is a concern that the rigidity of the housing 3 may be lowered, but the front left corner and the rear left corner of the partition plate 35 are fastened to the front left column 31 and the rear left column 33 with screws. Since the front surface, rear surface, and left surface of the partition plate 35 are fastened to the front plate 36, the rear plate 37, and the lower left plate 52 with screws, sufficient rigidity can be ensured. Further, between the partition plate 35 and the right side surface of the hollow portion 2, a transport frame 39 is fastened to the front right column 32 and the rear right column 34, and the front and rear side plates 36 and 37. Since it is connected to the partition plate 35 via 37, rigidity can be ensured also between the partition plate 35 and the right side surface of the hollow portion 2.

  In addition, in order to prevent intrusion of dust or the like from the opening 71 on the bottom surface, a bottom plate made of a light material such as resin can be provided in the opening 71. In this case as well, the weight can be reduced as compared with the bottom plate made of sheet metal material.

  Furthermore, since the front plate is not provided in the lower space 2a of the hollow portion 2, further weight reduction is possible, but when the front plate is not provided in the lower space 2a, the rigidity of the lower space 2a is reduced. Therefore, the lower left side plate 52, the partition plate 35 connected via the front and rear side plates 36, 37, the upper frame portion 54 of the conveyance frame 39, and the right frame portion 55 of the conveyance frame 39 are arranged from the front side of the lower space 2a. As seen, the impact applied to the bottom of the image forming apparatus 1 can be distributed to each of the columns 31, 32, 33, and 34 by forming a U-shape with an opening at the bottom. When the bottom plate is present, the impact concentrates on the bottom plate and deformation of the bottom plate and each side plate is likely to occur. However, deformation of the bottom plate and each side plate can be prevented by dispersing the impact. Furthermore, the rear side plate 37, the lower left side plate 52, and the right frame portion 55 of the transport frame 39 are formed in a U-shape with the front opening when viewed from the upper side of the lower space 2a. When a load is applied, the load can be distributed and received by each of the columns 31, 32, 33, 34.

  Furthermore, since the conveyance frame 39 is also used as the right side plate, the number of parts can be reduced, and the weight can be reduced and the cost can be reduced. In the present embodiment, the transport frame 39 has a structure having the upper frame portion 54 and the right frame portion 55, but the upper frame portion 54 is not necessarily provided. However, since the rigidity can be further increased by fastening the transport frame 39 to the front and rear side plates 36 and 37, it is preferable to provide the upper frame portion 54. It is also preferable to fasten the transport frame 39 and the partition plate 35 in order to increase the rigidity. Alternatively, a right side plate may be disposed on the right side surface of the hollow portion 2 separately from the transport frame 39.

  Further, since the image forming devices 11 and the conveying device 13 fixing device 21 are positioned by the front and rear side plates 36 and 37, the accumulated tolerance depending on the dimensional accuracy of the members supporting these devices can be reduced. Therefore, the alignment of each image forming device 11, the conveying device 13, and the fixing device 21 can be maintained with high accuracy, and high-quality image formation can be performed.

  Further, in the embodiment of the present invention, the case where the configuration of the present invention is applied to the color printer 1 has been described. However, in another different embodiment, an image forming apparatus other than the color printer 1 such as a copying machine, a facsimile machine, or a multifunction machine. The configuration of the present invention may be applied to.

  Furthermore, since the above description of the embodiment of the present invention describes a preferred embodiment of the image forming apparatus according to the present invention, there may be various technically preferable limitations. The technical scope of the present invention is not limited to these embodiments unless specifically described to limit the present invention. That is, the above-described components in the embodiment of the present invention can be appropriately replaced with existing components and the like, and various variations including combinations with other existing components are possible. The description of the embodiment of the present invention described above does not limit the contents of the invention described in the claims.

1 Color printer (image forming device)
2 Hollow part 2a Lower space 2b Upper space 3 Housing 6 Paper feed cassette 11 Image forming device 13 Conveying device 21 Fixing devices 31, 32, 33, 34 Post 35 Partition plate 36 Front plate (enclosure member)
37 Rear side plate (go member)
38 Left side plate (go member)
39 Conveying frame (going member)

Claims (8)

An image forming apparatus including a housing having a rectangular parallelepiped hollow portion in which an image forming unit is accommodated,
The housing is
Four struts respectively disposed at the four corners of the hollow portion and extending in the vertical direction;
Four surrounding members respectively fastened to two adjacent pillars among the four pillars and disposed on four sides of the hollow part,
An exterior cover covering the periphery of the four surrounding members;
And specifications cut plate you partitioning the hollow section into an upper space and a lower space,
Have
The partition plate has a rectangular base portion and a step portion that rises stepwise from an edge of the base portion, and a plurality of reinforcing recesses are formed in the base portion by sheet metal pressing. And being directly fastened to at least two of the four struts, and directly fastened to at least a pair of opposing surrounding members of the four surrounding members. Image forming apparatus. The upper space accommodates the image forming unit, and the lower space accommodates a paper feed cassette that accommodates a sheet formed by the image forming unit.
The four surrounding members include a front side plate, a rear side plate, a left side plate, and a right side plate, and the left side plate or the right side plate forms a conveyance path of the sheet from the sheet feeding cassette to the image forming unit. Transport frame
The image forming apparatus according to claim 1, wherein the transport frame is fastened to the front side plate and the rear side plate. The transport frame is the right side plate, and includes an upper frame that extends horizontally, and a right frame that is bent downward from an edge of the upper frame,
The image forming apparatus according to claim 2 , wherein a lattice-like rib is formed on the upper frame. The image forming unit includes a transport device that transports the sheet along the transport path, an image forming device that forms an image on the sheet transported by the transport device, and an image formed by the image forming device. A fixing device for fixing to the sheet,
The front the side plate and the rear plate, the image forming apparatus according to claim 2 or 3, characterized in that the positioning portion with the conveying device and the image forming apparatus and the fixing device is formed. 5. The image according to claim 3, wherein the partition plate, the left side plate, and the right side plate are formed in a U shape having an opening at the bottom when viewed from the front of the lower space. Forming equipment. The rear side plate and the left side plate wherein a right plate, as viewed from above of the lower space, any one of claims 2 to 5, characterized in that the front is formed in the shape of open ended U 1 The image forming apparatus described in the item. The bottom of the housing is open,
The image forming apparatus according to any one of claims 2-6, characterized in that the lower surface of the sheet feed cassette is exposed from the opening of the bottom surface of the housing. The bottom of the housing is open,
Wherein the opening of the bottom surface of the housing, an image forming apparatus according to any one of claims 2 to 6, characterized in that the resin base plate is provided.

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