JP2007017646A - Housing structure for image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce weight of a first housing after securing rigid strength of the first housing (lower housing 30) to which a second housing (upper housing 40) is selectively attached. <P>SOLUTION: The housing structure is used for an image forming apparatus 10 in which various image forming devices are fitted. The housing 20 includes: the lower housing 30 having a rectangular parallelepipedic shape, in which the main device of the image forming apparatus 10 is fitted; and the upper housing 40 to which additional devices (in the embodiment, an original cover 161 and an optical system unit 163) selectively integrally joined to the lower housing 30, are attached. Lower frames 50 having an L-shaped cross-section are fixed to the proper parts of the edges of the upper face of the lower housing 30 so that their insides face an outward into steps. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a housing structure of an image forming apparatus configured by incorporating various image forming devices.

  The image forming apparatus forms an image based on image information read or transmitted from the outside, and after transferring the image to a sheet, the sheet is discharged. Such an image forming apparatus is configured by mounting various precision devices for image formation inside a box-shaped housing. Recently, a so-called in-cylinder discharge type has been widely used. Yes.

  The in-body paper discharge type image forming apparatus includes a first housing in which main devices for image formation are housed, and a second housing integrally coupled to an upper portion of the first housing. A paper discharge space is formed between the first housing and the second housing for discharging the paper on which the transfer process has been completed.

  The first casing is electrostatically charged by irradiating a photosensitive drum, a charging device for forming a uniform charge on the circumferential surface of the photosensitive drum, and a light beam based on image information on the circumferential surface of the photosensitive drum. An exposure device that forms a latent image, a developing device that supplies toner to the electrostatic latent image on the peripheral surface of the photosensitive drum to form a toner image, and a toner on the peripheral surface that conveys paper toward the peripheral surface of the photosensitive drum A transfer device that transfers the image onto the paper, a fixing device that performs a fixing process on the transfer-processed paper that has been transferred by the transfer device, and remains on the peripheral surface of the photosensitive drum that has been transferred to the paper. A cleaning device for removing the residual toner and cleaning processing, a paper tray for storing paper, and the like are provided.

  The second casing is externally mounted with a document reading device for reading a document image from a document at the top thereof, and the document image information read by the document reading device is optically received inside the second casing. Optical equipment to be processed is built in.

  In the in-cylinder discharge type image forming apparatus configured as described above, when the image forming apparatus is configured as a copying machine, it is necessary to read a document image. Therefore, both the first and second casings are required. On the other hand, when the printer is used as a printer, since the original image is not read, the second housing is unnecessary, so only the first housing is used.

  Therefore, when the image forming apparatus is used as a printer, the first casing can be lowered in rigidity by the absence of the second casing, but the second casing is attached. The strength is set so as to withstand the mounting of the second housing.

  By the way, in order to increase the strength of the first housing, the thickness of the used frame is usually increased, or a pipe-shaped frame is used as the frame. Not only does this increase, but the housing weight increases, which makes it difficult to carry and carry the image forming apparatus.

  The present invention has been made in view of such a situation, and eliminates the difficulty of cost increase and handling after ensuring the rigid strength of the first housing to which the second housing is selectively attached. An object of the present invention is to provide a housing structure of an image forming apparatus capable of performing the above.

  The invention according to claim 1 is a housing structure of an image forming apparatus in which various image forming devices are installed, wherein the housing is a first housing having a rectangular parallelepiped shape in which main devices are installed. And a second housing for mounting additional equipment that is selectively and integrally coupled to the first housing, and the upper surface edge of the first housing has an L-shape in a sectional view. An L-shaped frame having a shape is fixed so that a stepped portion is formed on the edge of the upper surface with its inner surface facing outward.

  According to such a configuration, since the L-shaped frame having an L shape in a cross-sectional view is fixed to the upper surface edge of the first housing so as to have a stepped shape with the inner surface facing outward, By fixing the second housing to the vertical surface portion in a state where the second housing is fixed to the stepped plane portion of the L-shaped frame, the second housing is compared with the case where the second housing is simply fixed to the flat frame. The two housings are securely supported by the first housing.

  Accordingly, the strength of the first housing can be improved without increasing the thickness of the frame or using a pipe-shaped frame as in the prior art, thereby suppressing an increase in the weight of the first housing. Can contribute to cost reduction.

  According to a second aspect of the present invention, in the first aspect of the invention, a square pipe is formed in a state where the inner surface side of another L-shaped frame is opposed to the inner surface side of the L-shaped frame, and the second casing is It is supported by the square pipe.

  According to such a configuration, a square pipe is formed by joining another L-shaped frame to the L-shaped frame of the first housing, so that only the L-shaped frame is used without adopting a pipe-shaped frame from the beginning. A pipe-shaped frame is formed, thereby improving the housing strength while suppressing an increase in the weight of the first housing.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, in-cylinder discharge that discharges a sheet on which an image is formed by an image forming process between the first casing and the second casing. A space is formed.

  According to such a configuration, by fixing the second casing in a stacked state on the first casing, an in-cylinder discharge space is formed between the two casings, and thus the first and second casings in this state are predetermined. In this way, an in-cylinder discharge type image forming apparatus is obtained.

  According to the first aspect of the present invention, an L-shaped frame having an L-shape in a cross-sectional view is fixed to the upper surface edge of the first housing so as to be stepped with the inner surface facing outward. Therefore, when the second casing is simply fixed to the flat frame portion by fixing the second casing to the vertical surface portion in a state where the second casing is fixed to the stepped plane portion of the L-shaped frame. In comparison, the first housing can reliably support the second housing, thereby increasing the strength of the first housing by increasing the thickness of the frame as in the prior art or using a pipe-shaped frame. It is possible to improve the image forming apparatus without reducing the weight of the first housing, thereby contributing to the cost reduction of the image forming apparatus.

  According to the second aspect of the present invention, since the square pipe is formed by joining another L-shaped frame to the L-shaped frame of the first housing, the L-shaped pipe is not particularly adopted from the beginning. A pipe-shaped frame is formed only by the shape frame, and thereby the strength of the housing can be improved while suppressing an increase in the weight of the first housing.

  According to the third aspect of the present invention, since the in-cylinder discharge space is formed between the two cases by fixing the second case to the first case in a stacked state, An in-cylinder discharge type image forming apparatus can be manufactured by applying a predetermined outfitting to the second casing.

  First, an outline of an image forming apparatus to which a housing structure according to the present invention is applied will be described with reference to FIG. FIG. 1 is a front cross-sectional view for explaining an embodiment of the internal structure of the image forming apparatus.

  As shown in FIG. 1, an image forming apparatus 10 according to the present embodiment is used as a copying machine, and includes an apparatus main body 11 having a box shape and an original image provided on the upper part of the apparatus main body 11. The image reader 16 has a basic configuration. The apparatus main body 11 is formed by subjecting a lower casing (first casing) 30 (FIG. 2), which will be described later, to predetermined interior and exterior processing, and the image reading unit 16 will be described later. The upper housing (second housing) 40 (FIG. 2) is formed by performing predetermined interior and exterior treatments.

  The apparatus main body 11 has an image forming unit 12 that forms an image based on the image information of the original read by the image reading unit 16 and a fixing process performed on the image formed by the image forming unit 12 and transferred to the paper. A fixing unit 13 to be applied and a paper storage unit 14 for storing a transfer paper are provided.

  The image reading unit 16 is disposed so as to be opposed to the document retainer 161 via a contact glass 162 in the upper body of the apparatus main body 11 and a document retainer (additional device) 161 provided on the upper surface of the apparatus main body 11 so as to be opened and closed. The optical system unit (additional equipment) 163 is provided. The contact glass 162 is dimensioned to a planar shape slightly smaller than the document presser 161 in order to read the document surface of the placed document. The document presser 161 can be opened and closed by rotating forward and backward about a predetermined axis provided on one side of the upper surface of the housing, which is one component of the image reading unit 16.

  At an appropriate position of the image reading unit 16, an operation panel (not shown) for inputting processing conditions relating to document reading, copying processing, and the like is provided. The operation panel is provided with a display panel (not shown), a numeric keypad, a start button, a mode switching key, and the like.

  The optical system unit 163 includes a light source 164, a plurality of mirrors 165, a lens unit 166, and a CCD (charge coupled device) 167. Light from the light source 164 is reflected on the document surface via the contact glass 162, and this reflected light is input to the CCD 167 as document information via the plurality of mirrors 165 and the lens unit 166. Document information as an analog quantity input to the CCD 167 is converted into a digital signal and stored in a predetermined storage device.

  Incidentally, when a document is placed on the contact glass 162, the light source 164 moves and scans the document surface while the document is pressed by the document presser 161, while the document presser 161 moves the automatic paper feeder. When the document is also used and when the document is fed from the automatic paper feeder to the contact glass 162, the light source 164 scans the document surface being conveyed in a stopped state.

  The image forming unit 12 forms a toner image on a sheet fed from the sheet storage unit 14, and in the present embodiment, the image forming unit 12 sequentially arranges from the upstream side (the right side of the paper surface in FIG. 1) to the downstream side. A magenta unit 12M, a cyan unit 12C, a yellow unit 12Y, and a black unit 12K are provided.

  Each unit 12M, 12C, 12Y, and 12K includes a photosensitive drum 121 and a developing device 122, respectively. Each photosensitive drum 121 is supplied with toner from a corresponding developing device 122 while rotating counterclockwise in FIG. Each developing device 122 is supplied with toner from a toner cartridge 122 a disposed on the front side of the apparatus main body 11 (the front side of the paper surface of FIG. 1).

  A charger 123 is provided at a position directly below each photosensitive drum 121, and an exposure device 124 is provided at a position further below the charger 123. Each photosensitive drum 121 is charged uniformly by the charger 123, and laser light corresponding to each color based on the image data input by the image reading unit 16 is charged from each exposure device 124. By irradiating the peripheral surface of each photoconductive drum 121, an electrostatic latent image is formed on the peripheral surface of each photoconductive drum 121. By supplying toner from the developing device 122 to the electrostatic latent image, a toner image is formed on the peripheral surface of the photosensitive drum 121.

  A transfer belt 125 stretched between the driving roller 125 a and the driven roller 125 b is provided at a position above the photosensitive drum 121 so as to contact the photosensitive drum 121. The transfer belt 125 is driven against a peripheral surface of the photosensitive drum 121 by a transfer roller 126 provided corresponding to each photosensitive drum 121, and is driven with a driving roller 125a and a driven roller while being synchronized with the photosensitive drum 121. It circulates between 125b.

  Accordingly, when the transfer belt 125 circulates, the magenta toner image is transferred onto the surface of the transfer belt 125 by the photosensitive drum 121 of the magenta unit 12M, and then the photosensitive drum of the cyan unit 12C is placed at the same position on the transfer belt 125. The transfer of the cyan toner image by 121 is performed in the overcoating state, and then the transfer of the yellow toner image by the photosensitive drum 121 of the yellow unit 12Y to the same position of the transfer belt 125 is performed in the overcoating state. The transfer of the black toner image by the photosensitive drum 121 of the black unit 12K is performed in an overcoated state, whereby a color toner image is formed on the surface of the transfer belt 125. The color toner image formed on the surface of the transfer belt 125 is transferred to the paper P conveyed from the paper storage unit 14.

  A cleaning device 127 that removes and cleans residual toner on the peripheral surface of the photosensitive drum 121 is provided at the left position of each photosensitive drum 121 in FIG. The peripheral surface of the photosensitive drum 121 cleaned by the cleaning device 127 is directed to the charger 123 for a new charging process.

  The waste toner removed from the peripheral surface of the photosensitive drum 121 by the cleaning device 127 is collected in a toner collection bottle (not shown) through a predetermined path and stored.

  At the left position of the image forming unit 12 in FIG. 1, a paper conveyance path 111 extending in the vertical direction is formed. The sheet conveying path 111 is provided with a pair of conveying rollers 112 at appropriate positions, and the sheet from the sheet storage unit 14 is conveyed toward the transfer belt 125 that is wound around the driving roller 125a by the driving of the conveying roller pair 112. It has come to be. In the sheet conveyance path 111, a second transfer roller 113 that is in contact with the surface of the transfer belt 125 is provided at a position facing the driving roller 125 a, and the sheet P being conveyed along the sheet conveyance path 111 is separated from the transfer belt 125. The toner image on the transfer belt 125 is transferred to the paper P by being pressed and held between the second transfer roller 113 and the second transfer roller 113.

  The fixing unit 13 performs a fixing process on the toner image on the sheet transferred by the image forming unit 12, and includes a heating roller 131 including an energizing heating element such as a halogen lamp as a heating source inside the casing. The heating roller 131 and a pressure roller 132 disposed so as to face each other so that the peripheral surfaces thereof are in contact with each other. Then, the sheet P subjected to the transfer process by the rotating transfer belt 125 is supplied to the nip portion between the heating roller 131 and the pressure roller 132, thereby obtaining heat from the heating roller 131 and fixing process. The sheet is discharged through a discharge conveyance path 114 extended from the upper part of the fixing unit 13 toward an in-cylinder discharge tray 115 provided in the apparatus main body 11.

  The paper storage unit 14 has a paper tray 141 that is detachably mounted at a position below the exposure device 124 in the apparatus main body 11. A sheet bundle is stored in the sheet tray 141. In the present embodiment, the paper tray 141 is provided in two stages, and different sizes of paper P are stored. Then, the sheet P is fed out from the sheet bundle P1 stored in the selected sheet tray 141 one by one by driving the pickup roller 142, and passes through the sheet conveyance path 111 between the transfer belt 125 and the second transfer roller 113. It is conveyed toward the nip part.

  Further, a bypass transport unit 15 for transporting the manually fed paper P via the manual feed tray 151 is provided immediately below the exposure device 124, and the manually fed paper P is bypass transported. The paper is introduced into the paper conveyance path 111 through the bypass conveyance path 152 of the unit 15.

  The housing structure according to the present invention functions as a three-dimensional frame on which the various devices that are constituent elements constituting the internal structure of the image forming apparatus 10 are mounted. Hereinafter, the housing structure according to FIGS. 2 to 5 will be described.

  2 and 3 are perspective views showing an embodiment of the housing structure according to the present invention. FIG. 2 shows a state in which the lower housing and the upper housing are separated, and FIG. 3 shows the lower housing. And the upper housing are coupled to each other. 2 and 3, the XX direction is referred to as the left-right direction, and the Y-Y direction is referred to as the front-rear direction. In particular, the -X direction is leftward, the + X direction is rightward, the -Y direction is forward, and the + Y direction is forwarded. It is called the back.

  As shown in FIGS. 2 and 3, a casing 20 as a skeleton of an image forming apparatus 10 (indicated by a two-dot chain line in FIG. 3) used as a copying machine has main components for image forming processing mounted therein. A lower housing (first housing) 30 and an upper housing for mounting a document image reading device fixed to the lower housing 30 in a state of being stacked on the upper portion of the lower housing 30. (Second housing) 40.

  The lower housing 30 includes a bottom plate 31 that has a rectangular shape in plan view, four support columns 32 erected from four corners of the bottom plate 31, and the front two of the four support columns 32. A front plate 33 erected, a pair of side plates 34 erected between the two right and left columns 32, a back plate 35 erected between the two rear columns, A pair of front and rear beam frames 36 spanned between the tops of the two struts 32 and between the tops of the two rear struts 32 and a left beam spanned between the tops of the left two struts 32 A frame 38; a top plate 39 having a rectangular shape in plan view with four corners supported by the tops of the four columns 32; and a lower L-shaped frame 50 installed between the tops of the two columns on the right side. It is configured with.

  The bottom plate 31 is formed of a thin metal plate. The bottom plate 31 is provided with a plurality of reinforcing recesses 311 formed by pressing at appropriate positions, and has folded edges 312 formed by folding each edge upward by a predetermined amount. The rigidity is improved by the presence of the reinforcing recess 311 and the folded edge 312.

  Each of the support columns 32 is formed of a metal L-shaped member having an L-shape in a cross-sectional view in which a pair of long plate bodies 321 are integrally coupled so as to be perpendicular to each other at the side edges. One plate body 321 is attached to the bottom plate 31 by being screwed or welded to the folded edge 312 of the bottom plate 31 in a state of being erected at the corner.

  The front plate 33 is fixed in a screwed or welded state between the plate bodies 321 whose left and right edges are on the same plane of the pair of front columns 32 and whose upper edge is This is fixed to the front beam frame 36 by screwing or the like, so that each column 32 is reliably prevented from tilting in the left-right direction.

  The front plate 33 is provided with an upper mounting opening 331 that extends in the left-right direction at an upper position, and a lower mounting opening 332 that is wide open vertically and horizontally at the lower portion of the upper mounting opening 331.

  The upper mounting opening 331 is for detachably mounting the units 12M, 12C, 12Y, and 12K (FIG. 1) for image formation in the lower housing 30. Between the lower edge portion of the upper mounting opening 331 and the back plate 35, four pairs of guide rails 333 are laid in parallel with each other at an equal pitch. The units 12M, 12C, 12Y and 12K can be inserted into and removed from the lower housing 30 through the upper mounting opening 331 while being guided by a pair of target guide rails 333. The transfer belt 125 is attached to a portion above the units 12M, 12C, 12Y, and 12K and covered with the front plate 33.

  The lower mounting opening 332 is for detachably mounting the paper trays 141 (FIG. 1) and the bypass transport unit 15 in the lower housing 30. On the left side of the lower mounting opening 332, a partition plate 341 parallel to the side plate 34, which is slightly spaced from the left side plate 34, is provided. The partition plate 341 and the right side plate 34 are provided with two pairs of upper and lower guide members 334 extending in the front-rear direction, and each sheet tray 141 is a target within the guide members 334. The lower housing 30 can be inserted into and removed from the lower housing 30 while being guided by the pair of guide members 334.

  Further, a pair of upper guide members 335 extending in the front-rear direction facing left and right are provided at positions further above the upper guide member 334 in the lower mounting opening 332. The bypass transport unit 15 can be inserted into and removed from the lower housing 30 through the lower mounting opening 332 while being guided by the upper guide member 335.

  The exposure device 124 (FIG. 1) is mounted in a space between the upper mounting opening 331 and the lower mounting opening 332 in the lower housing 30 and covered with the front plate 33. At the same time, the toner cartridge 122a (FIG. 1) is detachably mounted on the front plate 33 above the upper mounting opening 331 in a position corresponding to each of the units 12M, 12C, 12Y, 12K. It has become.

  In addition, the paper conveyance path 111 (FIG. 1) is formed in the space between the left side plate 34 and the partition plate 341, and above the space and in front of the left side of the upper mounting opening 331. The fixing unit 13 is provided in a portion covered with the face plate 33.

  The right side plate 34 is provided with a manual tray mounting opening 342 for mounting the manual tray 151 at a substantially central portion in the vertical direction. The manual feed tray mounting opening 342 faces the bypass transport path 152 (FIG. 1) of the bypass transport unit 15, whereby the paper P manually fed via the manual feed tray 151 is introduced into the bypass transport path 152. Then, the sheet is supplied to the transfer process by the transfer belt 125 through the sheet conveyance path 111.

  In the lower housing 30 configured as described above, the front and rear beam frames 36 are provided with a pair of partition frames 37 facing each other in the front-rear direction at the left positions, and projecting upward. The left side 40 is supported by the pair of partition frames 37. A paper discharge conveyance path 114 (FIG. 1) for discharging the paper P on which the fixing process has been performed by the fixing unit 13 is formed between the pair of partition frames 37. Further, a dam frame 371 is installed at a lower right position between the pair of partition frames 37, and the paper P discharged through the paper discharge conveyance path 114 passes through the dam frame 371 and is discharged into the in-body discharge tray 115 ( 1 and 3).

  The top plate 39 is fixed to the front and rear beam frames 36 and the lower L-shaped frame 50 by screws or welding. The top plate 39 has a bulging portion 391 that is bulged upward except for the peripheral portion, and the bulging portion 391 spans between corners facing each other. The concave portion 392 formed in a cross shape is provided by being provided in a concave shape, and the top plate 39 is ensured to be rigid by forming such irregularities. An in-body discharge tray 115 (FIG. 3) is formed above the top plate 39.

  The lower L-shaped frame 50 is a stepped portion with the inner surface facing outward at the upper edge of the lower housing 30 (upper right edge of the lower housing 30 in the example shown in FIG. 2). It is fixed to form.

  The upper housing 40 is for housing the optical system unit 163 (FIG. 1), and has a rectangular frame 41 having a planar dimension substantially the same as the dimension of the lower housing 30 in plan view; An interposed body 44 interposed between the left end of the rectangular frame 41 and the pair of partition frames 37, and a column body suspended from the right rear corner toward the lower L-shaped frame 50. 45 and an upper L-shaped frame 60 integrally coupled to the rear end portion of the column 45 so as to face the lower L-shaped frame 50.

  The rectangular frame 41 includes a pair of front and rear long frames 42 that are set slightly shorter than the left and right dimensions of the lower housing 30 and a pair of left and right frames that are set slightly shorter than the front and rear dimensions of the lower housing 30. It consists of a short frame 43. Each of the long frame 42 and the short frame 43 employs a so-called C-shaped member having a C-shaped cross section, and are integrally coupled with the inner surfaces facing each other.

  The interposition body 44 is used for raising the height of the rectangular frame body 41 and is formed of a rectangular parallelepiped having a hollow interior. The interposition body 44 is fixed to the rectangular frame 41 by screwing or welding with the left end of the rectangular frame 41 being placed.

  The vertical dimension of the column body 45 is set to be substantially the same as the vertical dimension of the partition frame 37 and the interposition body 44, and the rectangular frame 41 is supported by the upper L-shaped frame 60. The horizontal posture is secured while being supported by the interposition body 44 and the column body 45.

  The upper L-shaped frame 60 is stacked on the lower L-shaped frame 50 in a state where the rear end thereof is integrally connected to the lower end of the column body 45 by screwing or welding. Thus, the upper housing 40 is integrally coupled to the lower housing 30.

  Then, as shown in FIG. 2, after the lower housing 30 and the upper housing 40 are assembled separately, the upper housing 40 is coupled to the upper portion of the lower housing 30 to obtain a copying machine as shown in FIG. The housing 20 of the image forming apparatus 10 is completed. Note that when the casing is used for a printer without the image reading unit 16, only the lower casing 30 shown in FIG. 2 is employed.

  4 and 5 are enlarged perspective views for explaining a coupling state of the lower L-shaped frame 50 and the upper L-shaped frame 60, FIG. 4 is an exploded perspective view, and FIG. 5 is an assembled perspective view. . 4 and 5, the direction display by X and Y is the same as in FIG. 2 ((X is the left-right direction (-X: leftward, + X: rightward), Y is the front-back direction (-Y: Front, + Y: back)).

  First, as shown in FIG. 4, the lower L-shaped frame 50 includes a first plate body 51 having a rectangular shape that is long in the front-rear direction, and a left edge portion of the first plate body 51. And a second plate body 52 having a rectangular shape elongated in the front-rear direction. A predetermined number of screw holes 53 extending in the front-rear direction are respectively screwed in the front and rear end surfaces of the first and second plate bodies 51 and 52 of the lower L-shaped frame 50, and are formed on the right edge end surface of the first plate body 51. Also, a predetermined number of screw holes 53 extending in the left-right direction are respectively screwed, and a predetermined number of screw holes 53 extending in the vertical direction are also screwed on the upper edge end surface of the second plate body 52.

  On the other hand, the plate body 321 corresponding to the lower L-shaped frame 50 of each support column 32 on the right side of the lower housing 30 has through holes 322 at positions facing the screw holes 53 on the respective end faces of the lower L-shaped frame 50. It has been drilled. Also, through holes 336 and 351 are formed in the front plate 33 and the back plate 35 of the lower housing 30 at positions facing the through holes 322 on the end surfaces of the support columns 32, respectively. Further, through-holes 361 are formed in the front and rear beam frames 36 at positions facing the through-holes 336 and 351 of the front plate 33 and the back plate 35, respectively.

  The lower L-shaped frame 50 is sandwiched between the plates 321, which are opposite to each other, and the plates 321 are further sandwiched between the front plate 33 and the back plate 35, and the front plate 33 and the back plate 35 are supported. After the face plate 35 is sandwiched between the front and rear beam frames 36, screws N are inserted into the through holes 361, 336 and 322 of the beam frame 36, the front plate 33 and the column 32 (however, the first L-shaped frame 50 first For the plate body 51, the screw N is penetrated only through the front plate 33 and the through holes 336 and 322 of the support column 32), and then the screw N is screwed into the screw hole 53 on the front end surface of the lower L-shaped frame 50. By fastening, the front end portion of the lower L-shaped frame 50 is fixed to the front column 32.

  Similarly, the rear end surface of the lower L-shaped frame 50 is also fixed to the rear column 32 by performing a screw fastening operation using the same screw N as in the case of the front end surface. Mounting to the housing 30 is completed. When the lower housing 30 is completed, the right upper edge of the lower housing 30 is stepped due to the presence of the lower L-shaped frame 50.

  As shown in FIG. 4, the upper L-shaped frame 60 includes a first plate body 61 having a rectangular shape elongated in the front-rear direction, a first plate body 61 parallel to the horizontal plane, and a right edge portion of the first plate body 61. It consists of the 2nd board 62 which exhibits the elongate rectangular shape in the front-back direction hanging down integrally. The front and rear end surfaces of the second plate body 62 of the upper L-shaped frame 60 are screwed with screw holes 63 extending in the front-rear direction, and the lower L-shape of the first plate body 61 is formed on the left edge. A predetermined number of through-holes 64 extending in the vertical direction corresponding to the screw holes 53 on the upper edge end surface of the second plate body 52 of the frame 50 are formed, respectively, and further, the lower edge portion of the second plate body 62 is provided with the lower portion. A predetermined number of through holes 64 extending in the left-right direction are formed corresponding to the screw holes 53 on the right end edge surface of the first plate body 51 of the L-shaped frame 50.

  On the other hand, the right surface of the lower end portion of the column body 45 suspended from the upper housing 40 is provided with a connection piece 451 that is slightly lowered from the end portion and protrudes forward. The second plate body 62 of the upper L-shaped frame 60 is fixed to the rear portion by screwing or welding. The top plate 39 of the lower housing 30 has a through hole 393 corresponding to the screw hole 53 screwed on the upper edge end surface of the second plate body 52 of the lower L-shaped frame 50 at the right edge thereof. It has been drilled.

  Such an upper L-shaped frame 60 is attached to the lower housing 30 so as to be covered with the lower L-shaped frame 50 fixed to the lower housing 30. Specifically, a through hole in which a screw N is drilled in the first plate body 61 of the upper L-shaped frame 60 in a state where the upper L-shaped frame 60 is covered by the lower L-shaped frame 50 via the top plate 39. 64 and the through hole 393 of the top plate 39 are screwed into a screw hole 53 screwed to the upper edge end surface of the second plate body 52 of the lower L-shaped frame 50, and the screw N continues to be connected to the beam frame 36 and the front frame. The face plate 33 (back plate 35) is screwed into the screw holes 53 on each end face of the second plate body 52 of the lower L-shaped frame 50, and the screw N is screwed to the front plate 33 (back plate 35) and the support column 32. The screw N is screwed into the screw hole 53 of the first plate 51 of the lower L-shaped frame 50 through the plate body 321, and the screw N is further threaded into the screw hole 63 on each end surface of the second plate 62 of the upper L-shaped frame 60. By screwing and fastening, the upper L-shaped frame 60 is lowered The upper housing 40 is fixed to the body 30, and the upper housing 40 is attached to the lower housing 30 in a state where the left side of the upper housing 40 is previously supported by the partition frame 37 of the lower housing 30. .

  In this state, the screw N is screwed to the right edge surface of the first plate body 51 of the lower L-shaped frame 50 through the through hole 64 formed in the second plate body 62 of the upper L-shaped frame 60. The lower L-shaped frame 50 and the upper L-shaped frame 60 are completely integrated by being screwed into the threaded holes 53 and fastened.

  Then, since the lower L-shaped frame 50 and the upper L-shaped frame 60 are integrated, a square pipe 70 as shown in FIG. 5 is formed in this portion. The rigid strength of can be greatly improved.

  As described above in detail, the case structure of the image forming apparatus 10 according to the present invention is employed in the image forming apparatus 10 in which various types of image forming devices are installed. A lower housing 30 having a rectangular parallelepiped shape in which main devices of the forming apparatus 10 are installed, and additional devices selectively coupled to the lower housing 30 (in this embodiment, the document presser 161 and the optical system unit). 163) A lower L-shaped frame 50 having an L-shape in a cross-sectional view has an inner surface outward at an appropriate position on the upper edge of the lower housing 30. Since the upper casing 40 is fixed to the vertical plane portion in a state where the upper casing 40 is fixed to the stepped plane portion of the lower L-shaped frame 50, the upper casing 40 is fixed. Is simply fixed to a flat frame In comparison, the lower housing 30 can reliably support the upper housing 40, thereby increasing the strength of the lower housing 30 and increasing the thickness of the frame as in the prior art or using a pipe-shaped frame. The image forming apparatus 10 can be reduced in cost by suppressing an increase in the weight of the lower housing 30.

  Further, the square pipe 70 is formed in a state where the inner surface side of the upper L-shaped frame 60 which is another L-shaped frame is opposed to the inner surface side of the lower L-shaped frame 50 of the lower housing 30, 40 is supported by this rectangular pipe 70, so that a pipe-shaped frame is formed only by an L-shaped frame without adopting a pipe-shaped frame from the beginning, thereby suppressing an increase in weight of the lower housing 30. In addition, the strength of the housing 20 can be improved.

  Furthermore, a space is provided between the lower housing 30 and the upper housing 40 for providing an in-cylinder discharge tray 115 for discharging the sheet onto which the image has been transferred by the image forming process. The in-cylinder discharge type image forming apparatus 10 can be easily manufactured by fixing the upper housing 40 in a stacked state and applying predetermined fittings to the lower housing 30 and the upper housing 40.

  The present invention is not limited to the above embodiment, and includes the following contents.

  (1) In the above embodiment, the image forming apparatus 10 as an in-cylinder discharge type copying machine manufactured mainly by stacking the upper casing 40 on the lower casing 30 has been described. The present invention is not limited to the image forming apparatus 10 being a copying machine, and the lower casing 30 is provided with a predetermined outfit without using the upper casing 40, whereby the image forming apparatus is used as a printer. You may make it manufacture. In this case, the upper L-shaped frame 60 is not stacked on the lower L-shaped frame 50 so that the square pipe 70 is not formed. However, since the upper housing 40 does not exist, the image forming apparatus is light in weight. There is no particular problem even if the pipe 70 is not formed.

  (2) In the above embodiment, the lower L-shaped frame 50 is provided only at the upper right edge of the lower housing 30, but in the present invention, the lower L frame 50 is disposed at the upper right edge of the lower housing 30. It is not limited to being provided, and may be provided on the other edge of the upper surface of the lower housing 30 depending on the situation.

  (3) In the above embodiment, the lower L-shaped frame 50 and the upper L-shaped frame 60 are integrated by screwing. However, in the present invention, the lower L-shaped frame 50 and the upper L-shaped frame 60 are integrated. It is not limited to being integrated by screwing, but may be integrated by welding.

  (4) In the above embodiment, the image forming apparatus 10 is an in-cylinder discharge type in which the paper P is discharged to the in-cylinder discharge tray 115 formed between the apparatus main body 11 and the image reading unit 16. However, the present invention is not limited to the in-cylinder discharge type of the image forming apparatus 10, and the paper discharge projecting outward from the side surface of the apparatus main body 11. It may be of a type that discharges to a tray. In this case, the L-shaped frame is applied to the upper edge portion of the apparatus main body 11.

  (5) In the above embodiment, the image forming apparatus 10 is used for color printing including a plurality of image forming units 12M, 12C, 12Y, and 12K. The apparatus 10 is not limited to being for color printing, but may be for monotone printing in which only black is printed.

It is explanatory drawing of front sectional view for demonstrating one Embodiment of the internal structure of an image forming apparatus. It is a perspective view showing one embodiment of the case structure concerning the present invention, and shows the state where the lower case and the upper case were separated. It is a perspective view showing one embodiment of the case structure concerning the present invention, and shows the state where the lower case and the upper case were combined. It is an expansion disassembled perspective view for demonstrating the combined state of a lower L-shaped frame and an upper L-shaped frame. It is an expansion assembly perspective view for demonstrating the combined state of a lower L-shaped frame and an upper L-shaped frame.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 11 Apparatus main body 111 Paper conveyance path 112 Conveyance roller pair 113 Transfer roller 114 Discharge conveyance path 115 In-cylinder discharge tray 12 Image forming part 121 Photosensitive drum 122 Developing device 122a Toner cartridge 123 Charger 124 Exposure device 125 Transfer Belt 125a Drive roller 125b Driven roller 126 Transfer roller 127 Cleaning device 12M Magenta unit 12C Cyan unit 12Y Yellow unit 12K Black unit 13 Fixing unit 131 Heating roller 132 Pressure roller 14 Paper storage unit 141 Paper tray 142 Pickup roller 15 Bypass transport unit 151 Tray 152 Bypass transport path 16 Image reading unit 162 Contact glass 163 Optical system unit 164 Light source 165 Mirror 16 Lens unit 20 Housing 30 Lower housing 31 Bottom plate 311 Reinforcing recess 312 Edge 32 Support column 321 Plate body 322 Through hole 33 Front plate 331 Upper mounting opening 332 Lower mounting opening 333 Guide rail 334 Guide member 335 Upper guide member 336 Through hole 34 Side plate 341 Bypass tray mounting opening 35 Back plate 51 Through hole 36 Beam frame 361 Through hole 37 Screen frame 371 Weir frame 38 Left beam frame 39 Top plate 391 Expanding portion 392 Cross recessed portion 393 Through hole 40 Upper housing 41 Rectangular shape Frame body 42 Long frame 43 Short frame 44 Interposition body 45 Column body 451 Connection piece 50 Shape frame 51 Plate body 52 Plate body 53 Hole 60 Shape frame 61 Plate body 62 Plate body 63 Hole 64 Through hole 70 Square pipe N Screw P Paper P1 Paper bundle

Claims (3)

A housing structure of an image forming apparatus in which various image forming devices are installed,
The casing is a first casing having a rectangular parallelepiped shape in which main equipment is installed,
A second housing for mounting an additional device that is selectively and integrally coupled to the first housing;
An L-shaped frame having an L shape in a cross-sectional view is fixed to the upper surface edge of the first housing so as to form a stepped portion on the upper surface edge with its inner surface facing outward. A housing structure for an image forming apparatus. A square pipe is formed with the inner surface side of another L-shaped frame facing the inner surface side of the L-shaped frame,
The image forming apparatus housing structure according to claim 1, wherein the second housing is supported by the square pipe.   3. The image according to claim 1, wherein an in-cylinder discharge space for discharging a sheet on which an image is formed by an image forming process is formed between the first casing and the second casing. Forming device housing structure.

Images