Image forming apparatus

Abstract

To increase the rigidity of an ejection port on the downstream side in a sheet ejection direction.SOLUTION: An image forming apparatus comprises: a housing having an ejection port; an upper device arranged above the housing; a first support member supporting the upper device; and a second support member supporting the upper device. The housing has a first side plate, a second side plate, and a frame member arranged downstream of the ejection port in a sheet ejection direction and connecting the first side plate and the second side plate to each other. In a sheet width direction, the first side plate and the first support member are arranged on a first side relative to the center of the housing, and the second side plate and the second support member are arranged on a second side opposite to the first side relative to the center of the housing. The frame member has a first surface connected with the first side plate, a second surface connected with the second side plate, a third surface connected with the first support member, and a fourth surface connected with the second support member.SELECTED DRAWING: Figure 14

Description

Technical Field

[0001] The present invention relates to an image forming apparatus that forms an image on a recording material.

Background Art

[0002] Patent Document 1 describes that the rigidity of an image forming apparatus is increased by fixing a conveyance guide to both the housing of the image forming apparatus and an option device fixed to the upper part of the housing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above document, the conveyance guide was provided on the upstream side of the discharge port in the sheet discharge direction in which the sheet is discharged from the discharge port of the housing.

[0005] An object of the present invention is to provide an image forming apparatus capable of increasing the rigidity on the downstream side of the discharge port in the sheet discharge direction.

Means for Solving the Problems

[0006] One aspect of the present invention is a housing that houses an image forming unit for forming an image on a sheet, the housing having a discharge port through which the sheet on which the image is formed by the image forming unit is discharged in a sheet discharge direction, an upper unit disposed above the housing, a first support member that supports the upper unit, and a second support member that supports the upper unit. In the image forming apparatus, the housing includes a first side plate that extends in a direction intersecting a sheet width direction orthogonal to the sheet discharge direction, a second side plate that extends in a direction intersecting the sheet width direction, and a frame member that is disposed downstream of the discharge port in the sheet discharge direction and connects the first side plate and the second side plate. In the sheet width direction, the first side plate and the first support member are disposed on a first side with respect to the center of the housing, the second side plate and the second support member are disposed on a second side opposite to the first side with respect to the center of the housing, and the frame member has a first surface connected to the first side plate, a second surface connected to the second side plate, a third surface connected to the first support member, and a fourth surface connected to the second support member. The image forming apparatus is characterized by the above.

Effect of the Invention

[0007] According to the present invention, it is possible to provide an image forming apparatus capable of enhancing the rigidity on the downstream side of the discharge port in the sheet discharge direction.

Brief Description of the Drawings

[0008]

Figure 1

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Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

[0010] In the following description and drawings, unless otherwise specified, the direction of gravity when the image forming apparatus 1 is installed on a horizontal plane is referred to as "down" or "downward", and the direction opposite to the direction of gravity is referred to as "up" or "upward". The downstream side of the sheet discharge direction D1 in which the sheet is discharged from the discharge port 100d (FIG. 1) of the printer main body 100 toward the discharge tray 135 is referred to as "front" or "forward", and the upstream side of the sheet discharge direction D1 is referred to as "rear" or "rearward". The right side when the image forming apparatus 1 is viewed from the front side is referred to as "right" or "rightward", and the left side when the image forming apparatus 1 is viewed from the front side is referred to as "left" or "leftward". The right and left sides are collectively referred to as the left-right direction. The left-right direction in the present embodiment is the sheet width direction orthogonal to the sheet discharge direction D1.

[0011] In the following description and drawings, unless otherwise specified, "connection" means connecting two members regardless of the connection method such as fastening using a fastener, welding between metals, adhesion using an adhesive, etc. "Fastening" means connecting two members using a fastener such as a screw or a bolt. Note that even if two members described below as being fastened to each other are basically replaced with a connection method other than fastening, it is also possible.

[0012] <<First Embodiment>> FIG. 1 is a schematic diagram showing the configuration of an image forming apparatus 1 according to the first embodiment. Above the printer main body 100 of the image forming apparatus 1, a sheet processing apparatus 200 that processes a sheet S output from the printer main body 100 is attached. Above the sheet processing apparatus 200, an original reading apparatus 300 that reads an original and an original conveying apparatus 400 that automatically conveys the original to the reading unit of the original reading apparatus 300 are attached.

[0013] That is, the image forming apparatus 1 according to the present embodiment is a multifunction machine including a printer main body 100, a sheet processing apparatus 200, an original reading apparatus 300, and an original conveying apparatus 400. That is, the image forming apparatus 1 has functions such as processing the sheet S on which an image is formed and reading an image from an original, in addition to the function of forming an image on the sheet S by the printer main body 100.

[0014] In the present embodiment, an image forming apparatus including at least one of a printer main body 100, a sheet processing apparatus 200, an original reading apparatus 300, and an original conveying apparatus 400 is referred to as a "multifunction printer" or a "multifunctional printer". Further, an image forming apparatus that does not include any of the sheet processing apparatus 200, the original reading apparatus 300, and the original conveying apparatus 400 is referred to as a "single-function printer".

[0015] As the sheet S which is a recording material (recording medium), various sheet materials with different sizes and materials can be used, such as paper like plain paper and cardboard, sheet materials with surface treatment like coated paper, sheet materials with special shapes like envelopes and index paper, plastic films, cloth, etc.

[0016] The printer main body 100 (image forming apparatus main body) has an image forming unit 100B as an image forming means and a housing 100A that houses the image forming unit 100B. The sheet processing apparatus 200 is an example of an upper apparatus disposed above the housing 100A.

[0017] The housing 100A includes a main body frame 100F described later. The housing 100A also includes members fixed to the main body frame 100F (for example, a cover member that forms the outer surface of the printer main body 100 and a guide member that forms a conveyance path for the sheet S inside the printer main body 100). Further, the components of the printer main body 100 described below may be incorporated as a part of the housing 100A or may be detachable from the housing 100A.

[0018] In addition, the housing 100A is provided with a discharge port 100d and a discharge tray 135. The discharge port 100d is an opening through which the sheet S on which an image is formed by the image forming unit 100B is discharged to the outside of the housing 100A. The moving direction of the sheet S discharged from the discharge port 100d is referred to as a sheet discharge direction D1. The discharge port 100d opens toward the front of the image forming apparatus 1.

[0019] The discharge tray 135 is a loading section on which the sheet S discharged from the discharge port 100d is loaded. The discharge tray 135 is provided on the upper surface of the housing 100A. The discharge tray 135 of the present embodiment is a surface provided on the upper surface of the housing 100A and inclined upward toward the front. In other words, the discharge tray 135 is a surface inclined upward toward the downstream side in the sheet discharge direction D1.

[0020] The image forming unit 100B includes a photosensitive drum 102 as an image carrier, a charging roller 103 as a charging means, a laser scanner 104 as an exposure means, a developing roller 105 as a developing means, and a transfer roller 106 as a transfer means. Further, the image forming unit 100B includes a fixing device 121 as a fixing means.

[0021] The photosensitive drum 102 is a drum-type electrophotographic photoreceptor. The photosensitive drum 102 is a member formed on the outer periphery of a cylindrical drum substrate formed of a photosensitive material such as OPC (organic photoconductor), amorphous selenium, or amorphous silicon with aluminum or nickel. The photosensitive drum 102 is rotationally driven by a drive source disposed in the housing 100A. The charging roller 103, the developing roller 105, and the transfer roller 106 are disposed around the photosensitive drum 102. Further, the laser scanner 104 is disposed above the photosensitive drum 102.

[0022] A transfer nip 101 as a transfer section where the toner image is transferred to the sheet S is formed between the transfer roller 106 and the photosensitive drum 102. The transfer roller 106 is biased toward the photosensitive drum 102 by a biasing member.

[0023] The fixing device 121 includes a fixing roller (heating roller), a pressure roller facing the fixing roller, and a heating means such as a halogen lamp for heating the fixing roller. The fixing device 121 may be of a film heating type in which a ceramic heater is disposed inside a cylindrical film.

[0024] At least a part of the image forming unit 100B may be provided in a cartridge that is detachable from the housing 100A. In the present embodiment, the photosensitive drum 102, the charging roller 103, and the developing roller 105 are provided in the process cartridge 107 that is integrally detachable from the housing 100A.

[0025] The printer main body 100 is provided with a sheet feeding unit 111, a pair of conveyance rollers 114, a pair of registration rollers 115, a pair of post-fixing rollers 132, a pair of discharge rollers 134, a discharge tray 135, a pair of reversing rollers 136, and a pair of re-conveyance rollers 137. The sheet feeding unit 111 includes a cassette 112 in which sheets S are stacked and stored, and a feeding unit 113 that feeds the sheets S one by one from the cassette 112. Each of the sheet feeding unit 111, the pair of conveyance rollers 114, the pair of registration rollers 115, the pair of post-fixing rollers 132, the pair of discharge rollers 134, the pair of reversing rollers 136, and the pair of re-conveyance rollers 137 can be said to include rollers for conveying the sheet S. In the present embodiment, the directions of the rotation axes of these rollers are parallel.

[0026] The pair of discharge rollers 134 is an example of a discharging means for discharging the sheet S on which an image is formed to the outside of the housing 100A of the printer main body 100. The sheet width direction is a direction parallel to the direction of the rotation axis of the rollers of the pair of discharge rollers 134. The pair of discharge rollers 134 discharges the sheet S toward the front side of the image forming apparatus 1 through the discharge port 100d of the housing 100A. The pair of reversing rollers 136 is an example of a reversing means for reversing the sheet S during double-sided printing.

[0027] The sheet processing apparatus 200 is an apparatus that receives the sheet on which an image is formed by the image forming unit 100B of the printer main body 100 from the housing 100A of the printer main body 100 and performs processing on the sheet. The sheet processing apparatus 200 is also called a finisher.

[0028] The sheet processing apparatus 200 includes a first discharge roller pair 201, a fixed discharge tray 210, an entrance roller pair 203, a processing unit 204, a second discharge roller pair 207, and a movable discharge tray 211. Also, a branched conveyance path is provided in the housing 200A of the sheet processing apparatus 200. The first discharge roller pair 201 and the fixed discharge tray 210 are arranged in the first conveyance path. The entrance roller pair 203, the processing unit 204, the second discharge roller pair 207, and the movable discharge tray 211 are arranged in a second conveyance path branched from the first conveyance path. The fixed discharge tray 210 is fixed to the housing 200A. The movable discharge tray 211 is movable (vertically movable) with respect to the housing 200A.

[0029] The processing unit 204 has a processing stage 206 that supports the sheet S, and a discharge roller 205 that discharges the sheet S to the processing stage 206. Also, the processing unit 204 has a processing mechanism capable of performing at least one process on the sheet S, such as a binding process for binding a plurality of sheets S or a punching process for punching holes in the sheet S.

[0030] The document reading apparatus 300 is an image reading apparatus that reads image information from a document. The image forming apparatus 1 including the document reading apparatus 300 can form an image on a sheet based on the image information read by the document reading apparatus 300.

[0031] The document reading apparatus 300 includes a glass surface 301 on which a document is placed, and a reading unit 302 that reads an image of the document. The document conveyance apparatus 400 includes a document tray 402 on which documents are stacked, a document feeding unit 401 that feeds a document from the document tray 402, a conveyance roller pair 403 that conveys the fed document toward the reading unit 302, and a conveyance guide 404 that guides the document.

[0032] (Operation of the image forming apparatus) Next, the operation of the image forming apparatus 1 will be described. When an execution instruction (print command) for the image forming operation is input to the image forming apparatus 1, the image forming apparatus 1 starts the image forming operation. First, the photosensitive drum 102 is rotationally driven at a predetermined peripheral speed (process speed). The charging roller 103 uniformly charges the surface of the photosensitive drum 102 to a predetermined polarity and a predetermined potential. The laser scanner 104 irradiates the surface of the photosensitive drum 102 with laser light based on the image information input from an external computer together with the print command or the image information read from the document by the document reading apparatus 300, thereby exposing the photosensitive drum 102. As a result, the charges in the exposed areas on the surface of the photosensitive drum 102 are removed, and an electrostatic latent image corresponding to the image information is formed. The developing roller 105 supplies toner as a developer to the photosensitive drum 102 and develops the electrostatic latent image into a toner image. The toner image formed on the photosensitive drum 102 is conveyed toward the transfer nip 101 by the rotation of the photosensitive drum 102.

[0033] On the other hand, the sheet S is fed one by one from the cassette 112 by the feeding unit 113. The fed sheet S is conveyed to the transfer nip 101 after being subjected to skew correction and timing adjustment by the registration roller pair 115 via the conveying roller pair 114. Then, at the transfer nip 101, the toner image is transferred from the photosensitive drum 102 to the sheet S.

[0034] The sheet S that has passed through the transfer nip 101 is sent to the fixing device 121. The fixing device 121 sandwiches and conveys the sheet S at the fixing nip between the fixing roller and the pressure roller, and heats and pressurizes the toner image on the sheet S to fix the toner image to the sheet S.

[0035] The sheet S that has passed through the fixing device 121 is guided by the first switching member 131 to a conveyance path specified in advance in the printing instruction. When performing single-sided printing for forming an image on one side of the sheet S, the sheet S is guided by the first switching member 131 to the post-fixing roller pair 132. When performing double-sided printing for forming images on both sides of the sheet S, the sheet S on which an image has been formed on the first side is guided by the first switching member 131 to the inversion roller pair 136. After the sheet S is inversely conveyed (switched back) by the inversion roller pair 136, it is conveyed again to the transfer nip 101 via the re-conveyance roller pair 137. Then, the sheet S on which an image has been formed on the second side opposite to the first side by passing through the transfer nip 101 and the transfer nip is guided by the first switching member 131 to the post-fixing roller pair 132.

[0036] In the present embodiment, the sheet S on which the image formation for single-sided printing or double-sided printing has been completed is conveyed via the post-fixing roller pair 132. When not sending the sheet S to the sheet processing device 200, the sheet S that has passed through the post-fixing roller pair 132 is guided by the second switching member 133 to the discharge roller pair 134. In this case, the sheet S is discharged to the outside of the housing 100A through the discharge port 100d by the discharge roller pair 134 and is stacked on the discharge tray 135. When sending the sheet S to the sheet processing device 200, the sheet S that has passed through the post-fixing roller pair 132 is guided by the second switching member 133 to a conveyance path leading to the sheet processing device 200. In this case, the sheet S is discharged to the outside of the housing 100A through a discharge port communicating with the sheet processing device 200 and is received by the sheet processing device 200.

[0037] The sheet S received by the sheet processing device 200 from the printer main body 100 is guided by the switching member 202 to the conveyance path specified in advance in the print command. When no processing is performed on the sheet S, the sheet S is guided by the switching member 202 to the discharge roller pair 201 and discharged to the fixed discharge tray 210 by the discharge roller pair 201. When processing is performed on the sheet S, the sheet S is guided by the switching member 202 to the inlet roller pair 203 and conveyed toward the processing unit 204 by the inlet roller pair 203. The processing unit 204 discharges the sheet S to the processing stage 206 by the discharge roller 205 and performs processing such as binding processing or punching processing on the sheet S. The processed sheet S is discharged to the movable discharge tray 211 by the discharge roller pair 207.

[0038] (Operations of the document reading device and the document conveyance device) Next, the operations of the document reading device 300 and the document conveyance device 400 will be described. The document reading device 300 and the document conveyance device 400, and the document conveyance device 400 can execute a continuous reading operation of reading the image of a document while conveying the document. In the continuous reading operation, the documents stacked on the document tray 402 are fed one by one by the document feeding unit 401, guided by the conveyance guide 404, and conveyed to the glass surface 301 of the document reading device 300 through the conveyance roller pair 403. The reading unit 302 of the document reading device 300 optically scans the document through the glass surface 301 and acquires image information obtained by converting the image of the document into electronic data. The document read by the reading unit 302 is discharged to the discharge tray provided in the document conveyance device 400.

[0039] (Frame of the printer main body) The main body frame 100F of the printer main body 100 will be described. First, the outline of the main body frame 100F will be described with reference to FIGS. 2 and 3. FIGS. 2 and 3 are perspective views showing a part of the frame of the image forming apparatus 1 according to the first embodiment. Note that FIGS. 2 and 3 are views of the main body frame 100F and the left apparatus support member 151 among the frames of the image forming apparatus 1 shown in FIGS. 14 and 15. As will be described later, the frame of the image forming apparatus 1 includes the main body frame 100F, the frame 200F of the sheet processing apparatus 200, the left apparatus support member 151, the right inner apparatus support member 260, the right outer apparatus support member 261, and the like.

[0040] As shown in FIGS. 2 and 3, the main body frame 100F has a right side plate 140, a left side plate 141, a scanner stay 142, a bottom stay 143, a front stay 144, a front upper stay 145, a rear upper stay 146, and a rear lower stay 147. The main body frame 100F also includes an extended member right 148 connected to the right side plate 140 and an extended member left 150 connected to the left side plate 141. The right side plate 140 is an example of a first side plate. The left side plate 141 is an example of a second side plate. The front upper stay 145 is an example of a frame member. In the axial direction of the rotation axis of the photosensitive drum 102, the right side plate 140 is disposed on one end side of the process cartridge 107, and the left side plate 141 is disposed on the other end side of the process cartridge 107. The process cartridge 107 is detachably attached to the housing 100A in a direction (preferably orthogonal) intersecting the axial direction of the rotation axis of the photosensitive drum 102. Each of the right side plate 140 and the left side plate 141 is provided with a guide member for guiding the attachment of the process cartridge 107 to the housing 100A and a positioning portion for positioning the process cartridge 107 at the image forming position.

[0041] The right side plate 140 is provided on the right side of the main body frame 100F and is a plate-shaped frame member that extends in the front-rear direction and the up-down direction. That is, the right side plate 140 is disposed on the first side with respect to the center of the housing 100A in the sheet width direction and extends in a direction intersecting the sheet width direction. The left side plate 141 is provided on the left side of the main body frame 100F and is a plate-shaped frame member that extends in the front-rear direction and the up-down direction. That is, the left side plate 141 is disposed on the second side opposite to the first side with respect to the center of the housing 100A in the sheet width direction and extends in a direction intersecting the sheet width direction. In other words, the right side plate 140 is disposed on one end side with respect to the center of the housing 100A, and the left side plate 141 is disposed on the other end side opposite to the one end side with respect to the center of the housing 100A. Also, it can be said that the right side plate 140 is disposed on the first side with respect to the center of the main body frame 100F in the sheet width direction, and the left side plate 141 is disposed on the second side opposite to the first side with respect to the center of the main body frame 100F in the sheet width direction. In other words, the right side plate 140 is disposed on one end side with respect to the center of the main body frame 100F, and the left side plate 141 is disposed on the other end side opposite to the one end side with respect to the center of the main body frame 100F.

[0042] The paper feed unit 113, laser scanner 104, and core unit 160 of the printer main body 100 are arranged between the right side plate 140 and the left side plate 141 in the left - right direction and are respectively attached to the main body frame 100F. The paper feed unit 113 and the core unit 160 are fastened to the right side plate 140 and the left side plate 141 using, for example, screws that penetrate from the outside to the inside of the right side plate 140 and the left side plate 141. That is, the right side plate 140 and the left side plate 141 support the paper feed unit 113 and the core unit 160. The laser scanner 104 is placed on the scanner stay 142 and is fastened to the scanner stay 142. Note that the core unit 160 is a unit including a pair of conveyance rollers 114, a pair of registration rollers 115, a transfer roller 106, and a pair of re - conveyance rollers 137 (see FIG. 1). The core unit 160 forms a conveyance path through which the sheet S passes. In the present embodiment, the core unit 160 forms the conveyance path of the sheet S when single - sided printing is performed and the conveyance path of the sheet S when double - sided printing is performed. Also, the core unit 160 has a plurality of guide ribs for guiding the sheet S passing through these conveyance paths.

[0043] The scanner stay 142, bottom stay 143, front stay 144, front - upper stay 145, and rear - lower stay 147 are frame members that connect the right side plate 140 and the left side plate 141, respectively. Details of the front - upper stay 145 and the rear - upper stay 146 will be described later.

[0044] The scanner stay 142 is arranged above the mounting space where the process cartridge 107 is mounted (see also FIG. 1). The bottom stay 143 connects the bottom of the right side plate 140 and the bottom of the left side plate 141 at a position in front of the central position of the housing 100A in the front - rear direction. The front stay 144 connects the front part of the right side plate 140 and the front part of the left side plate 141. The front - upper stay 145 connects the upper part of the right side plate 140 and the upper part of the left side plate 141 at a position in front of the central position of the housing 100A in the front - rear direction. The rear - lower stay 147 connects the rear part of the right side plate 140 and the rear part of the left side plate 141 at a position below the central position of the housing 100A in the up - down direction.

[0045] In this embodiment, the scanner stay 142 and the bottom stay 143 are fastened to the right side plate 140 and the left side plate 141 by screws penetrating from the outside to the inside of the right side plate 140 and the left side plate 141. The front stay 144 is directly fastened to the front surface of the left side plate 141, while being fastened to the front stay mounting plate 153 (FIG. 2) fastened to the right side plate 140, and thus is mounted on the right side plate 140 via the front stay mounting plate 153. The rear lower stay 147 is fastened to the rear surfaces of the right side plate 140 and the left side plate 141.

[0046] Each stay (142 to 147) is a substantially flat plate-shaped metal member (sheet metal) extending in the left-right direction. Each stay (142 to 147) may be subjected to drawing, hemming, or bending. The right side plate 140 and the left side plate 141 are also substantially flat plate-shaped metal members (sheet metal). The right side plate 140 and the left side plate 141 may be subjected to drawing, hemming, or bending.

[0047] Further, as shown in FIG. 3, an installation hole 141a for installing the fixing device 121 is provided at the rear part of the left side plate 141. By providing the installation hole 141a, the space between the right side plate 140 and the left side plate 141 when viewed from the rear is widened. Therefore, when assembling the printer main body 100, the fixing device 121 can be inserted from the rear side of the main body frame 100F, and the fixing device 121 can be attached to the main body frame 100F. A reinforcing plate 152 that connects the upper edge and the lower edge of the installation hole 141a on the rear surface of the left side plate 141 is provided on the left side plate 141 and is fastened to the left side plate 141. The left side plate 141 is reinforced by the reinforcing plate 152, and a decrease in the strength of the main body frame 100F due to the provision of the installation hole 141a is suppressed.

[0048] (Expansion member) Here, the right expansion member 148 and the left expansion member 150 will be described. The image forming apparatus 1 of this embodiment can be changed to another product form in which some of the components are common to the image forming apparatus 1 but the functions and performances are different depending on the presence or absence of the expansion member.

[0049] Figures 4 and 5 are diagrams showing an image forming apparatus 2 as an example of another product form (a modification of the first embodiment). The image forming apparatus 2 is a single-function printer. FIG. 4 is a perspective view showing the frame 2F of the image forming apparatus 2. FIG. 5 is a schematic view of the image forming apparatus 2. Hereinafter, the right extension member 148 and the left extension member 150 in the image forming apparatus 1 of the first embodiment will be described while comparing with the image forming apparatus 2 of the modification example that does not have the right extension member 148 and the left extension member 150.

[0050] In the image forming apparatus 2 of the modification example, the sheet conveyance path during double-sided printing, the number of sheets that can be stacked on the discharge tray 135, etc. are different from those of the image forming apparatus 1 (FIG. 1) of the first embodiment. Hereinafter, in the image forming apparatus 2, members denoted by the same reference numerals as those of the image forming apparatus 1 of the first embodiment shall have substantially the same configuration and function as the corresponding members of the image forming apparatus 1 of the first embodiment.

[0051] As shown in FIG. 4, the frame 2F of the image forming apparatus 2 of the modification example does not have the right extension member 148 and the left extension member 150 (FIG. 2) of the first embodiment. Further, the frame 2F has a rear upper stay 1460 instead of the rear upper stay 146 of the first embodiment, and has a front upper stay 1450 instead of the front upper stay 145 of the first embodiment.

[0052] In the image forming apparatus 2 of the modification example, the rear upper stay 1460 is fastened to the upper surface and the rear surface of the right side plate 140 and the upper surface and the rear surface of the left side plate 141.

[0053] On the other hand, in the image forming apparatus 1 of the first embodiment, as shown in FIGS. 2 and 3, the right extension member 148 is attached to the rear part of the upper surface of the right side plate 140, and the left extension member 150 is attached to the rear part of the upper surface of the left side plate 141. The right extension member 148 is an example of a first extension member disposed above the first side plate and connected to the first side plate. The left extension member 150 is an example of a second extension member disposed above the second side plate and connected to the second side plate.

[0054] The rear upper stay 146 is fastened to the upper and rear surfaces of the right extension member 148 and the upper and rear surfaces of the left extension member 150. A reinforcing plate 149 (Fig. 2) is provided at the location on the upper surface of the right side plate 140 where the right extension member 148 is attached. The reinforcing plate 149 reinforces the upper surface of the right side plate 140 to suppress the inclination of the right extension member 148 with respect to the right side plate 140.

[0055] As shown in Fig. 5, the image forming apparatus 2 without an extension member does not have the discharge roller pair 134 and the reverse roller pair 136 (Fig. 1) of the first embodiment. The image forming apparatus 2 has a triple roller 134A as a discharge means for discharging the sheet S and a reverse means for reversing the sheet S during double-sided printing. The triple roller 134A includes a discharge reverse roller 1340, a discharge idler roller 1341 that contacts the discharge reverse roller 1340, and a reverse idler roller 1342 that contacts the discharge reverse roller 1340.

[0056] The sheet S that has passed through the fixing device 121 is guided by the switching member 138 to the nip portion (discharge nip) between the discharge reverse roller 1340 and the discharge idler roller 1341 or the nip portion (reverse nip) between the discharge reverse roller 1340 and the reverse idler roller 1342. The sheet S for which image formation for single-sided printing or double-sided printing has been completed is guided to the discharge nip by the switching member 138 and discharged to the discharge tray 135 by the discharge reverse roller 1340 and the discharge idler roller 1341. When performing double-sided printing, the sheet S having an image formed on the first side is guided to the reverse nip by the switching member 138. The sheet S is reversely conveyed (switched back) by the discharge reverse roller 1340 and the reverse idler roller 1342, and then conveyed again to the transfer nip 101 via the re-conveying roller pair 137. Then, the sheet S having an image formed on the second side opposite to the first side by passing through the transfer nip 101 and the transfer nip is guided to the discharge nip by the switching member 138.

[0057] Comparing FIG. 2 and FIG. 4, in the main body frame 100F of the first embodiment having the extension member, the rear part of the main body frame 100F extends upward compared to the frame 2F without the extension member. Therefore, the discharge roller pair 134 (FIG. 1) of the image forming apparatus 1 of the first embodiment can be arranged at a higher position compared to the discharge reversing roller 1340 and the discharge idler roller 1341 (FIG. 5) of the image forming apparatus 2 without the extension member. That is, at least a part of the discharge roller pair 134 is arranged above the upper surfaces of the right side plate 140 and the left side plate 141 by utilizing the space of the housing 100A extended by the right extension member 148 and the left extension member 150. Thereby, the number of sheets that can be stacked on the discharge tray 135 can be made larger.

[0058] Note that if the position of the discharge roller pair 134 is raised, depending on the momentum of the sheet S during discharge, the sheet S may jump over the discharge tray 135 and fall. Therefore, by increasing the inclination angle A of the discharge tray 135 as described later, the sheet S can be more reliably landed on the discharge tray 135.

[0059] Also, the conveyance distance from the fixing device 121 to the discharge roller pair 134 in the image forming apparatus 1 of the first embodiment having the extension member is longer than the conveyance distance from the fixing device 121 to the discharge nip in the image forming apparatus 2 (FIG. 5) without the extension member. In the image forming apparatus 1 (FIG. 1) of the first embodiment, a dedicated reversing roller pair 136 for reversing the sheet S during double-sided printing can be arranged separately from the discharge roller pair 134 for discharging the sheet S. Therefore, by driving and controlling the reversing roller pair 136 at a timing and driving speed independent of the discharge roller pair 134, the productivity during double-sided printing can be improved compared to the image forming apparatus 2 without the extension member.

[0060] (Front upper stay) Next, the front upper stay 145 of the image forming apparatus 1 of the first embodiment will be described while comparing it with the front upper stay 1450 of the image forming apparatus 2.

[0061] As shown in FIG. 4, in the image forming apparatus 2, the front upper stay 1450 is fastened to the upper surfaces of the right side plate 140 and the left side plate 141. The front upper stay 1450 is disposed on the downstream side of the discharge tray 135 in the sheet discharge direction D1. Here, the "downstream side of the discharge tray 135 in the sheet discharge direction D1" refers to a position where the distance to the downstream end of the discharge tray 135 in the sheet discharge direction D1 is shorter than the distance to the upstream end of the discharge tray 135 in the sheet discharge direction D1. That is, the front upper stay 1450 is disposed at a position where the distance to the downstream end of the discharge tray 135 in the sheet discharge direction D1 is shorter than the distance to the upstream end of the discharge tray 135 in the sheet discharge direction D1. Further, the discharge tray 135 is a surface that slopes upward toward the front among the upper surface portions of the printer main body 100.

[0062] The front upper stay 1450 is a substantially flat plate-shaped member extending in the left-right direction. The front upper stay 1450 may be subjected to drawing or hemming for reinforcement.

[0063] As shown in FIG. 2, in the image forming apparatus 1 of the first embodiment, the front upper stay 145 is fastened to the upper surfaces of the right side plate 140 and the left side plate 141. FIG. 6 is a schematic view showing the positional relationship between the discharge tray 135 and the front upper stay 145, and represents a cross-sectional view of the housing 100A in a plane perpendicular to the left-right direction.

[0064] As shown in FIG. 6, the front upper stay 145 is disposed downstream of the discharge port 100d of the housing 100A in the sheet discharge direction D1. The front upper stay 145 is disposed downstream of the discharge tray 135 in the sheet discharge direction D1. That is, the front upper stay 145 is disposed at a position where the distance to the downstream end of the discharge tray 135 in the sheet discharge direction D1 is shorter than the distance to the upstream end of the discharge tray 135 in the sheet discharge direction D1. The discharge tray 135 is inclined upward toward the downstream in the sheet discharge direction D1 and extends to a position higher than the upper ends 140t of the right side plate 140 and 141t of the left side plate 141. That is, the downstream end of the discharge tray 135 is located above the front upper stay 145. Also, among the ends of the housing 100A, the end located upstream of the discharge port 100d in the sheet discharge direction D1 is referred to as the upstream end, and the end located downstream of the discharge port 100d is referred to as the downstream end. At this time, as shown in FIG. 6, when viewed in the sheet width direction, the position of the front upper stay 145 is closer to the downstream end of the housing 100A than to the upstream end of the housing 100A. That is, the distance between the front upper stay 145 and the downstream end of the housing 100A is shorter than the distance between the front upper stay 145 and the upstream end of the housing 100A.

[0065] The front upper stay 145 has two side plate connection surfaces 145d respectively connected to the right side plate 140 and the left side plate 141, and support member connection surfaces 145a and 145b respectively connected to a device support member right inner 260 (FIG. 14) and a device support member left 151 described later. The front upper stay 145 also has an intermediate portion 145c that connects the right side plate connection surface 145d and the support member connection surface 145b on the right side and the left side plate connection surface 145d and the support member connection surface 145a on the left side.

[0066] The side plate connection surface 145d connected to the right side plate 140 is the first surface of the front upper stay 145. The side plate connection surface 145d connected to the left side plate 141 is the second surface of the front upper stay 145. The support member connection surface 145b connected to the device support member right inner 260 is the third surface of the front upper stay 145. The support member connection surface 145a connected to the device support member left 151 is the fourth surface of the front upper stay 145.

[0067] The right side plate connection surface 145d is connected to the upper surface of the right side plate 140. The right side plate connection surface 145d and the upper surface of the right side plate 140 are surfaces that extend in a direction intersecting the vertical direction, and in this embodiment, they are surfaces that extend in the horizontal direction. The left side plate connection surface 145d is connected to the upper surface of the left side plate 141. The left side plate connection surface 145d and the upper surface of the left side plate 141 are surfaces that extend in a direction intersecting the vertical direction, and in this embodiment, they are surfaces that extend in the horizontal direction. The right support member connection surface 145b is connected to the right inner 260 of the device support member above the upper surface of the right side plate 140. The left support member connection surface 145a is connected to the left 151 of the device support member above the upper surface of the left side plate 141.

[0068] The side plate connection surface 145d and the support member connection surfaces 145a, 145b of the front upper stay are formed of a single metal plate. The metal plate is bent between the right side plate connection surface 145d extending substantially in the front-rear direction and the right support member connection surface 145b extending substantially in the up-down direction, and is also bent between the left side plate connection surface 145d extending substantially in the front-rear direction and the left support member connection surface 145a extending substantially in the up-down direction.

[0069] As shown in FIG. 16, the middle portion 145c has a surface 145e (the fifth surface) continuous with the left and right side plate connection surfaces 145d and a surface 145f (the sixth surface) continuous with the left and right support member connection surfaces 145a, 145b. The surface 145e is a surface that extends in a direction intersecting the vertical direction. In this embodiment, the surface 145e extends in the left-right direction so as to connect the left and right side plate connection surfaces 145d and extends in a substantially front-rear direction (horizontal direction). The surface 145f is a surface that extends in a direction intersecting the horizontal direction. In this embodiment, the surface 145f extends in the left-right direction so as to connect the left and right support member connection surfaces 145a, 145b and extends in a substantially up-down direction (vertical direction).

[0070] The surfaces 145e and 145f of the middle portion 145c are formed of the same metal plate as the side plate connection surface 145d and the support member connection surfaces 145a and 145b. The metal plate is bent between a surface 145e extending substantially in the front-rear direction and a surface 145f extending substantially in the vertical direction when viewed in the left-right direction. By making the cross-sectional shape of the middle portion 145c bent when viewed in the left-right direction, the rigidity of the front upper stay 145 itself can be increased compared to the case where the cross-sectional shape of the middle portion 145c is linear, and the effect of improving the rigidity of the main body frame 100F by the front upper stay 145 can be further enhanced. Further, since the surface 145f is a surface continuous with the support member connection surfaces 145a and 145b, the upper device (sheet processing device 200) supported via the support member connection surfaces 145a and 145b can be supported more stably.

[0071] As shown in FIG. 16, the middle portion 145c can have a U-shaped cross section in which the surface 145e extends upward from the front end of the surface 145e and the surface 145g extends upward from the rear end of the surface 145e. Thereby, further improvement in the rigidity of the front upper stay 145 and the main body frame 100F can be achieved.

[0072] As shown in FIG. 6, when viewed in the left-right direction, the upper end 145c1 of the middle portion 145c of the front upper stay 145 is located above the upper end 140t of the right side plate 140 and the upper end 141t of the left side plate 141. Also, the middle portion 145c of the front upper stay 145 is located below the discharge tray 135. That is, in the present embodiment, when viewed in the sheet width direction, the upper end of the middle portion of the frame member is located above the upper surfaces of the first side plate and the second side plate and below the loading portion.

[0073] Also, the middle portion 145c of the front upper stay 145 is disposed between the right side plate 140 and the left side plate 141 in the left-right direction. The middle portion 145c of the front upper stay 145 may support the lower surface of the discharge tray 135.

[0074] The support member connection surfaces 145a and 145b are arranged outside the discharge tray 135 in the left - right direction. That is, in the left - right direction, the discharge tray 135 is arranged between the support member connection surfaces 145a and 145b. At least one upper end of the support member connection surfaces 145a and 145b protrudes upward from the upper end 145c1 of the surface 145f of the intermediate portion 145c (FIG. 2). That is, at least one of the upper ends of the third surface and the fourth surface of the frame member is located above the upper end of the intermediate portion of the frame member. In the present embodiment, both upper ends of the support member connection surfaces 145a and 145b protrude upward from the upper end 145c1 of the surface 145f of the intermediate portion 145c.

[0075] Note that it is preferable that the front - upper stay 145 has a greater plate thickness and stronger rigidity compared to the front - upper stay 1450 shown in FIG. 4. It is preferable that the front - upper stay 145 has a greater plate thickness and stronger rigidity compared to the right - side plate 140 and the left - side plate 141. The front - upper stay 145 may be subjected to drawing or hemming for reinforcement.

[0076] (Device support member left) Next, the device support member left 151 disposed on the upper surface of the left - side plate 141 in the image forming apparatus 1 of the first embodiment will be described. As shown in FIG. 2, the device support member left 151 is installed between the left - side expansion member 150 and the front - upper stay 145 in the front - rear direction. The device support member left 151 is connected to the upper surface of the left - side expansion member 150 and the upper surface of the left - side plate 141, and is also connected to the support member connection surface 145a of the front - upper stay 145.

[0077] As shown in FIG. 13, the device support member left 151 is provided with positioning protrusions 151a and 151b. The positioning protrusions 151a and 151b are convex shapes protruding forward from the front surface of the device support member left 151, and are formed, for example, by drawing a part of the metal plate forming the device support member left 151.

[0078] On the support member connection surface 145a of the front upper stay 145, positioning holes 145a1 and 145a2 that respectively fit with the positioning protrusions 151a and 151b of the device support member left 151 are provided. When the positioning holes 145a1 and 145a2 fit with the positioning protrusions 151a and 151b, the left extension member 150 is suppressed from tilting with respect to the upper surface of the left side plate 141.

[0079] (Image processing unit) Next, the image processing unit 505 included in the image forming apparatus 1 of the first embodiment will be described. The image forming apparatus 1 of the present embodiment is configured to be able to mount a document reading apparatus 300 and a document conveyance apparatus 400 on the upper part of the printer main body 100 by replacing the image processing unit from the image forming apparatus 2 (FIGS. 4 and 5) of the modification example and changing the position of the fan.

[0080] FIG. 7(a) is a schematic view showing a state of viewing the frame 2F of the image forming apparatus 2 of the modification example from the left side. FIG. 7(b) is a schematic view showing a state of viewing the main body frame 100F of the image forming apparatus 1 of the first embodiment from the left side.

[0081] As shown in FIG. 7(a), the image forming apparatus 2 includes fans 502 and 503, an operation control unit 500, and an image processing unit 501. The fans 502 and 503 take in external air and blow it into the apparatus. The operation control unit 500 is a circuit board including a control circuit that controls the operation of the image forming apparatus 2 (for example, the above-described image forming operation). The image processing unit 501 is a circuit board including a control circuit that processes image information sent from an external computer together with a print command and converts it into data for driving the laser scanner 104.

[0082] In the image forming apparatus 2, the fans 502 and 503, the operation control unit 500, and the image processing unit 501 are arranged outside (left side) of the left side plate 141. The fan 502 is arranged above the operation control unit 500, and the fan 503 is arranged above the image processing unit 501. The fans 502 and 503, the operation control unit 500, and the image processing unit 501 are all located inside the silhouette (rectangular outer edge) of the left side plate 141 when viewed from the left side.

[0083] On the other hand, in the image forming apparatus 1 of the first embodiment which is a multifunction machine, in order to process the image information read by the document reading apparatus 300 and perform image processing for realizing the FAX function, the processing ability required for the image processing unit is greater than that of the image forming apparatus 2 which is a single-function printer. Therefore, the image forming apparatus 1 of the first embodiment has an image processing unit 505 larger than the image processing unit 501 (FIG. 7(a)) of the modified example.

[0084] As shown in FIG. 7(b), the image processing unit 505 of the first embodiment does not fit inside the silhouette (rectangular outer edge) of the left side plate 141 when viewed from the left. Specifically, a part of the upper portion of the image processing unit 505 protrudes above the silhouette of the left side plate 141.

[0085] In the image forming apparatus 1 of the first embodiment, an extension member left 150 is installed on the upper surface of the left side plate 141. The width of the image processing unit 505 in the vertical direction is within the range from the lower end of the left side plate 141 to the upper end of the extension member left 150.

[0086] Further, the image forming apparatus 1 of the first embodiment has a fan 504 instead of the fan 503 (FIG. 7(a)) of the modified example image forming apparatus 2. The fan 504 is disposed inside the apparatus support member left 151 when viewed from the left. The apparatus support member left 151 is a substantially rectangular recess when viewed from the left and has a recess opened toward the left, and the fan 504 is accommodated in this recess.

[0087] The image processing unit 505 is disposed behind the operation control unit 500. At least a part of the apparatus support member left 151 is located behind the rear end of the operation control unit 500 in the front-rear direction. Also, at least a part of the apparatus support member left 151 is located in front of the front end of the image processing unit 505 in the front-rear direction.

[0088] Next, the image processing unit case 170 as a case member to which the image processing unit 505 is attached will be described with reference to FIGS. 8 and 9. FIG. 8 is a perspective view showing the main body frame 100F to which the image processing unit case 170 is attached. FIG. 9 is a perspective view showing the main body frame 100F before the image processing unit case 170 is attached. The image processing unit case 170 is a part of the housing 100A of the printer main body 100.

[0089] As shown in FIGS. 8 and 9, the image processing unit case 170 has a case main body 170a and an interface board 171 integrated therewith, and is formed in a substantially box shape. The interface board 171 is formed with a plurality of holes for allowing connectors to be attached to interface portions such as a LAN connector and a USB connector provided in the image processing unit 505.

[0090] A part of the image processing unit case 170 protrudes above the upper surface of the left side plate 141. An attachment plate 162 is provided on the left side plate 141. The image processing unit case 170 is fixed to the left side plate 141 by fastening the case main body 170a to the attachment plate 162 and fastening the interface board 171 to the rear surface of the left side plate 141. Further, the image processing unit case 170 is fastened to each of the left extension member 150 and the left device support member 151.

[0091] In this way, in the present embodiment, the device support member left 151 and the left side plate 141 are connected via the image processing unit case 170. In other words, the case member is connected to each of the second side plate and the second support member. Therefore, compared with a configuration in which the device support member left 151 and the left side plate 141 are not connected via the image processing unit case 170, the inclination of the device support member left 151 with respect to the left side plate 141 is suppressed. By suppressing the inclination of the device support member left 151, the inclination of the upper device (sheet processing device 200) supported by the device support member left 151 is also suppressed.

[0092] In addition, since the image processing unit case 170 is further connected to the left extension member 150, the left extension member 150 and the left side plate 141 are connected via the image processing unit case 170. Therefore, compared with a configuration in which the left extension member 150 and the left side plate 141 are not connected via the image processing unit case 170, the inclination of the left extension member 150 with respect to the left side plate 141 is suppressed. By suppressing the inclination of the left extension member 150, the inclination of the upper device (sheet processing device 200) supported by the left extension member 150 is also suppressed.

[0093] (Frame configuration of the sheet processing device) The frame configuration of the sheet processing device 200 will be described with reference to FIGS. 10 and 11. FIGS. 10 and 11 are perspective views showing the frame 200F of the sheet processing device 200.

[0094] The frame 200F of the sheet processing device 200 includes a right side plate 220, a left side plate 221, a top plate 224, a bottom plate 222, and a front bottom stay 223. The right side plate 220, the left side plate 221, the top plate 224, the bottom plate 222, and the front bottom stay 223 are fastened to each other to form a substantially box shape.

[0095] In addition, the frame 200F includes an electrical installation plate 225, a front plate 226, and a reinforcing plate 227. The electrical installation plate 225 and the front plate 226 are attached to the front surface of the left side plate 221 and are disposed at positions protruding forward with respect to the substantially box shape formed by the right side plate 220, the left side plate 221, the top plate 224, the bottom plate 222, and the front bottom stay 223. The reinforcing plate 227 is fastened to the upper surface of the left side plate 221 and the upper surface of the electrical installation plate 225. The reinforcing plate 227 firmly connects the left side plate 221 and the electrical installation plate 225.

[0096] On the lower part of the sheet processing device 200, a right attachment part 230 and a left attachment part 240 are provided. The right attachment part 230 and the left attachment part 240 are attachment parts for attaching the sheet processing device 200 to the printer main body 100. The right attachment part 230 and the left attachment part 240 are positioning parts for positioning the sheet processing device 200 with respect to the printer main body 100.

[0097] The right attachment part 230 includes a resin-made right attachment member 231. A first positioning shaft 232 that engages with the printer main body 100 protrudes from the right attachment member 231. The left attachment part 240 includes a left attachment member 241 formed in a box shape from sheet metal. A second positioning shaft 242 that engages with the printer main body 100 protrudes from the left attachment member 241.

[0098] (Connection configuration of the sheet processing device and the document reading device) The connection configuration of the sheet processing device 200 and the document reading device 300 will be described with reference to FIG. 12. FIG. 12 is a schematic view of the sheet processing device 200 and the document reading device 300 as seen from the left side.

[0099] As shown in FIG. 12, a pedestal 310 is provided on the top plate 224 of the sheet processing device 200. The pedestal 310 may be pre-assembled in the sheet processing device 200, or may be a member separate from the sheet processing device 200 and the document reading device 300. The pedestal 310 is a support member that supports a device installed above the sheet processing device 200. The pedestal 310 is made of resin and also has functions such as a cable guide that guides a cable connecting the document reading device 300 and the sheet processing device 200 or the printer main body 100. In the present embodiment, the document reading device 300 is installed on the pedestal 310, and the document reading device 300 and the sheet processing device 200 are integrated via the pedestal 310.

[0100] Note that the document conveyance device 400 is pre-integrated with the document reading device 300 by being connected to the document reading device 300 via, for example, a hinge part. That is, by attaching the document reading device 300 on the pedestal 310, the document conveyance device 400 is also assembled to the image forming apparatus 1.

[0101] (Connection configuration of the printer main body and the sheet processing device) The connection configuration between the printer main body 100 and the sheet processing device 200 will be described with reference to FIGS. 13 to 16. FIG. 13 is a perspective view showing the right extension member 148, the left extension member 150, and the left device support member 151, and corresponds to an enlarged view of the upper part of FIG. 2. FIGS. 14, 15, and 16 are perspective views showing the frame configuration of the image forming apparatus 1 with the sheet processing device 200 installed on the upper part of the printer main body 100.

[0102] First, the positioning configuration between the sheet processing device 200 and the printer main body 100 will be described. As shown in FIG. 13, the printer main body 100 is provided with a right positioning hole 252 and a left positioning hole 253 as positioning portions for positioning the sheet processing device 200. The right positioning hole 252 is formed on the upper surface of the right extension member 148. The left positioning hole 253 is formed on the upper surface of the left extension member 150.

[0103] The sheet processing device 200 is configured such that the first positioning shaft 232 (FIG. 11) fits into the right positioning hole 252 and the second positioning shaft 242 fits into the left positioning hole 253, thereby determining the position of the sheet processing device 200 relative to the printer main body 100.

[0104] Next, the connection between the sheet processing device 200 and the printer main body 100 will be described. As shown in FIG. 13, a plurality of brackets 251a to 251e for fastening the sheet processing device 200 and the printer main body 100 are installed on the right extension member 148, the left extension member 150, and the left device support member 151. Specifically, brackets 251a and 251b are fastened to the upper surface of the right extension member 148. A bracket 251c is fastened to the upper surface of the left extension member 150. Brackets 251d and 251e are fastened to the upper surface of the left device support member 151. In addition, a fastening portion 254 for fastening the sheet processing device 200 and the printer main body 100 is also provided at the upper end portion of the image processing unit case 170.

[0105] The sheet processing device 200 is installed on the right extension member 148, the left extension member 150, and the left device support member 151. The right attachment portion 230 (Figs. 10 and 11) of the sheet processing device 200 is fastened to brackets 251a and 251b. The left attachment portion 240 (Figs. 10 and 11) of the sheet processing device 200 is fastened to bracket 251c and the fastening portion 254 of the image processing unit case 170. The front plate 226 (Figs. 10 and 11) of the sheet processing device 200 is fastened to brackets 251d and 251e. In this way, the sheet processing device 200 is connected to the printer main body 100 via the brackets 251.

[0106] As shown in Fig. 14, on the upper surface of the right side plate 140, between the right extension member 148 and the front upper stay 145, an inner right device support member 260 and an outer right device support member 261 are provided.

[0107] The inner right device support member 260 is an example of a first support member, and the aforementioned left device support member 151 is an example of a second support member. The inner right device support member 260 is formed by one or more sheet metals. The inner right device support member 260 may be formed by bent sheet metal or may be formed by a plurality of sheet metals. The left device support member 151 is formed by one or more sheet metals. The left device support member 151 may be formed by bent sheet metal or may be formed by a plurality of sheet metals. The inner right device support member 260 supports the sheet processing device 200 on the right side of the image forming apparatus 1. That is, the inner right device support member 260 supports the upper device on the first side in the sheet width direction. The left device support member 151 supports the sheet processing device 200 on the left side of the image forming apparatus 1. That is, the left device support member 151 supports the upper device on the second side opposite to the first side in the sheet width direction.

[0108] Note that the first support member and the second support member are not limited to being directly connected to the upper device, and may support the upper device by being connected to other members connected to the upper device. In the present embodiment, the right inner device support member 260 as the first support member supports the sheet processing device 200 by being connected to the right outer device support member 261 connected to the sheet processing device 200. The right inner device support member 260 and the right outer device support member 261 may be formed as an integral member.

[0109] The right inner device support member 260 is attached to the upper surface of the right side plate 140 and also to the support member connection surface 145b of the front upper stay 145. More specifically, the right inner device support member 260 is fastened to the upper surface of the right side plate 140 and also to the support member connection surface 145b of the front upper stay 145. Further, the right inner device support member 260 is fastened to the bracket 251b (FIG. 16).

[0110] The right outer device support member 261 is fastened to the right surface of the right inner device support member 260. Also, the upper connection surface 261a of the right outer device support member 261 is connected to the frame 200F of the sheet processing device 200. Further, the right outer device support member 261 is also fastened to the right side attachment member 231 (FIGS. 10 and 11) of the sheet processing device 200.

[0111] In this way, in the present embodiment, the frame 200F of the sheet processing device 200 and the main body frame 100F of the printer main body 100 are connected via the right inner device support member 260 and the right outer device support member 261. Therefore, compared with the case where the frame 200F of the sheet processing device 200 and the main body frame 100F of the printer main body 100 are not connected via the right inner device support member 260 and the right outer device support member 261, the sheet processing device 200 and the printer main body 100 can be connected more firmly.

[0112] Further, the upper connection surface 261a of the right outer device support member 261 is fastened to the top plate 224 of the sheet processing device 200. That is, the right inner device support member 260 is connected to the upper surface of the sheet processing device 200 via the right outer device support member 261 connected to the right inner device support member 260. With this configuration, the sheet processing device 200 and the printer main body 100 can be more firmly connected. Note that at least one of the first support member and the second support member may be connected to the upper surface of the upper device.

[0113] Also, as shown in FIG. 14, the image forming apparatus 1 is provided with a connection plate 250. The connection plate 250 is fastened to the front plate 226 of the sheet processing device 200 and the front surface of the left device support member 151, respectively, and connects the front plate 226 and the left device support member 151.

[0114] In this way, in the present embodiment, the frame 200F of the sheet processing device 200 and the main body frame 100F of the printer main body 100 are connected via the left device support member 151 and the connection plate 250. Therefore, compared with the case where the frame 200F of the sheet processing device 200 and the main body frame 100F of the printer main body 100 are not connected via the left device support member 151 and the connection plate 250, the sheet processing device 200 and the printer main body 100 can be more firmly connected.

[0115] As described above, the sheet processing device 200 is installed on the right extension member 148, the left extension member 150, and the left device support member 151, and is connected to the printer main body 100 via a plurality of brackets 251a to 251e and the image processing unit case 170. The sheet processing device 200 is supported by the right extension member 148 and the left extension member 150 at the rear side of the image forming apparatus 1, and is supported by the right inner device support member 260 and the left device support member 151 at the front side of the image forming apparatus 1.

[0116] On the right front side of the image forming apparatus 1, a device support member right inner 260 as a first support member is provided. The device support member right inner 260 is installed on the upper surface of the right side plate 140 of the main body frame 100F and fastened to a support member connection surface 145b which is the standing surface of the front upper stay 145. Thereby, the device support member right inner 260 is suppressed from tilting with respect to the right side plate 140. Then, by fastening the device support member right outer 261 to the device support member right inner 260 and the top plate 224 of the sheet processing apparatus 200, the sheet processing apparatus 200 itself is also suppressed from tilting with respect to the right side plate 140.

[0117] On the left front side of the image forming apparatus 1, a device support member left 151 as a second support member is provided. The device support member left 151 is attached to the upper surface of the left side plate 141 of the main body frame 100F and the upper surface of the extension member left 150, and also attached to a support member connection surface 145a which is the standing surface of the front upper stay 145. More specifically, the device support member left 151 is installed on the upper surface of the left side plate 141 of the main body frame 100F and the upper surface of the extension member left 150, and fastened to a support member connection surface 145a which is the standing surface of the front upper stay 145. By fitting the positioning protrusions 151a, 151b of the device support member left 151 into the positioning holes 145a1, 145a2 of the support member connection surface 145a, the device support member left 151 is suppressed from tilting with respect to the left side plate 141. Then, the sheet processing apparatus 200 is connected to the device support member left 151 via brackets 251d, 251e, and the front plate 226 of the device support member left 151 and the sheet processing apparatus 200 are connected by a connecting plate 250 on the front side of the device. Thereby, the sheet processing apparatus 200 itself is also suppressed from tilting with respect to the left side plate 141.

[0118] According to the present embodiment described above, the support member connection surfaces 145a and 145b of the front upper stay 145 disposed on the front side of the image forming apparatus 1 are connected to the left device support member 151 and the right inner device support member 260, respectively. That is, the front upper stay 145 (frame member) disposed downstream of the discharge port 100d in the sheet discharge direction D1 has a third surface (support member connection surface 145b) connected to the right inner device support member 260 and a fourth surface (support member connection surface 145a) connected to the left device support member 151. Therefore, it is possible to enhance the rigidity on the downstream side of the image forming apparatus in the sheet discharge direction.

[0119] Normally, the user stands in front of the image forming apparatus 1 and performs operations such as opening and closing the document conveyance apparatus 400 and taking out sheets from the discharge tray 135. At this time, if there is no sense of unity between the housing 100A of the printer main body 100 and the upper device, there is a possibility of giving an impression of lack of rigidity.

[0120] Further, the image forming apparatus 1 is provided with wheels at the bottom of the apparatus to transport the entire apparatus, or the entire apparatus is loaded on a cart. When moving the entire apparatus, the user or operator may support the document reading apparatus 300 and the sheet processing apparatus 200 and overcome steps and gaps or move on an inclined surface. At this time, if the frame of the sheet processing apparatus 200 is twisted or tilted, there is a possibility of giving an impression of lack of unity between the housing 100A of the printer main body 100 and the upper device and lack of rigidity.

[0121] According to the present embodiment, it is possible to provide an image forming apparatus capable of enhancing the rigidity on the downstream side of the discharge port in the sheet discharge direction.

[0122] <<Second Embodiment>> The second embodiment will be described with reference to FIG. 17. Hereinafter, elements denoted by the same reference numerals as those in the first embodiment have substantially the same configurations and functions as those described in the first embodiment unless otherwise specified, and differences from the first embodiment will be mainly described.

[0123] In the second embodiment, a document reading device 300 and a document conveyance device 400 are attached above the housing 100A of the printer main body 100. The document reading device 300 is an example of an upper device disposed above the housing 100A.

[0124] FIG. 17 is a perspective view showing the frame configuration of the image forming apparatus 1A according to the second embodiment. In the second embodiment, an extension member right 148 and a device support member right 512 are installed on the right side plate 140, and a column member 510 is installed on the extension member right 148. Further, an extension member left 150 and a device support member left 151 are installed on the left side plate 141, and a column member 511 is installed on the extension member left 150 and the device support member left 151. The document reading device 300 (FIG. 1) is installed on the upper surfaces of the column members 510 and 511.

[0125] In this way, the column members 510 and 511 are provided between the extension member right 148, the extension member left 150, the device support member right 512, the device support member left 151, and the document reading device 300. Thereby, the distance from the discharge tray 135 (FIG. 1) of the printer main body 100 to the bottom surface of the document reading device 300 can be increased, and the number of sheets that can be stacked on the discharge tray 135 can be increased.

[0126] The device support member right 512 is disposed behind the front upper stay 145 and in front of the extension member right 148. The device support member right 512 is fastened to the support member connection surface 145b of the front upper stay 145 and is also fastened to the column member 510. Further, the upper surface of the column member 510 and the upper surface of the device support member right 512 are positioned at substantially the same height in the product height direction. Then, the document reading device 300 is connected to the upper surfaces of the column members 510 and 511 and the upper surface of the device support member right 512. Thereby, the document reading device 300 and the printer main body 100 are connected.

[0127] According to the configuration described above, the document reading device 300 is connected to the printer main body via the extension member right 148, the extension member left 150, the device support member left 151, the device support member right 512, and the column members 510 and 511.

[0128] On the right front side of the image forming apparatus 1A, a right device support member 512 as a first support member is provided. The right device support member 512 is connected to the upper surface of the right side plate 140 of the main body frame 100F and is also connected to a support member connection surface 145b which is the standing surface of the front upper stay 145. Thereby, the inclination of the right device support member 512 with respect to the right side plate 140 is suppressed. And by connecting the right device support member 512 and the document reading device 300, the inclination of the document reading device 300 itself with respect to the right side plate 140 is also suppressed.

[0129] On the left front side of the image forming apparatus 1A, a left device support member 151 as a second support member is provided. With the same configuration as the first embodiment, the inclination of the left device support member 151 with respect to the left side plate 141 is suppressed. And the document reading device 300 is connected to the left device support member 151 via the column member 511. Thereby, the inclination of the document reading device 300 itself with respect to the left side plate 141 is also suppressed.

[0130] According to the present embodiment described above, the support member connection surfaces 145a and 145b of the front upper stay 145 arranged on the front side of the image forming apparatus 1A are connected to the left device support member 151 and the right device support member 512 respectively. That is, the front upper stay 145 (frame member) arranged downstream of the discharge port 100d in the sheet discharge direction D1 has a third surface (support member connection surface 145b) connected to the right device support member 512 and a fourth surface (support member connection surface 145a) connected to the left device support member 151. Therefore, in the image forming apparatus 1A, it is possible to enhance the rigidity on the downstream side of the discharge port in the sheet discharge direction.

[0131] According to the present embodiment, it is possible to provide an image forming apparatus capable of enhancing the rigidity on the downstream side of the discharge port in the sheet discharge direction.

[0132] (Other Embodiments) In each of the above-described embodiments, the sheet processing device 200 and the document reading device 300 are exemplified as examples of the upper device, but the upper device may be other devices.

[0133] In the first embodiment, the image forming apparatus 1 as a multifunction peripheral including the sheet processing apparatus 200, the document reading apparatus 300, and the document conveying apparatus 400 is exemplified, and the image forming apparatus 2 as a single function printer is exemplified as a modification of the first embodiment. As a further modification of the first embodiment, the image forming apparatus may be a single function printer having the right extension member 148 and the left extension member 150 and not including the sheet processing apparatus 200, the document reading apparatus 300, and the document conveying apparatus 400.

[0134] The above-described image forming unit 100B is an example of an image forming means. The image forming means may be, for example, an intermediate transfer type electrophotographic mechanism that transfers a toner image formed on the photosensitive drum 102 to a sheet via an intermediate transfer body. The image forming means may be a mechanism that forms a color image using a plurality of color developers. Further, the image forming means may be a mechanism other than the electrophotographic method, such as an inkjet method or an offset printing method.

[0135] "Summary of the Present Disclosure" The present disclosure includes at least the following configurations or methods.

[0136] (Configuration 1) A housing that houses an image forming means for forming an image on a sheet, the housing having a discharge port through which the sheet on which the image is formed by the image forming means is discharged in the sheet discharge direction, An upper device disposed above the housing, A first support member that supports the upper device, A second support member that supports the upper device, An image forming apparatus comprising: The housing includes: A first side plate extending in a direction intersecting with the sheet width direction orthogonal to the sheet discharge direction, A second side plate extending in a direction intersecting with the sheet width direction, A frame member disposed downstream of the discharge port in the sheet discharge direction and connecting the first side plate and the second side plate, And having In the sheet width direction, the first side plate and the first support member are arranged on a first side with respect to the center of the housing, and the second side plate and the second support member are arranged on a second side opposite to the first side with respect to the center of the housing. The frame member has a first surface connected to the first side plate, a second surface connected to the second side plate, a third surface connected to the first support member, and a fourth surface connected to the second support member. An image forming apparatus characterized by the above.

[0137] (Configuration 2) The housing has a stacking portion on which the sheet discharged from the discharge port is stacked. The frame member is arranged at a position where the distance to the downstream end of the stacking portion in the sheet discharge direction is shorter than the distance to the upstream end of the stacking portion in the sheet discharge direction. The image forming apparatus according to Configuration 1, characterized by the above.

[0138] (Configuration 3) The first surface is connected to the upper surface of the first side plate. The second surface is connected to the upper surface of the second side plate. The third surface is connected to the first support member above the upper surface of the first side plate. The fourth surface is connected to the second support member above the upper surface of the second side plate. The image forming apparatus according to Configuration 1 or 2, characterized by the above.

[0139] (Configuration 4) The first surface, the second surface, the third surface, and the fourth surface are formed of a single metal plate. The metal plate is bent between the first surface and the third surface, and the metal plate is bent between the second surface and the third surface. The image forming apparatus according to Configuration 3, characterized by the above.

[0140] (Configuration 5) The frame member has a fifth surface that extends in the sheet width direction and connects the first surface and the second surface, and a sixth surface that extends in the sheet width direction and connects the third surface and the fourth surface. When viewed in the sheet width direction, the metal plate is bent between the fifth surface and the sixth surface. The image forming apparatus according to Configuration 4, characterized in that.

[0141] (Configuration 6) The frame member has an intermediate portion that extends in the sheet width direction and connects the first surface and the second surface. At least one of the upper end of the third surface and the upper end of the fourth surface is located above the upper end of the intermediate portion. The image forming apparatus according to any one of Configurations 1 to 5, characterized in that.

[0142] (Configuration 7) The frame member has an intermediate portion that extends in the sheet width direction and connects the first surface and the second surface. The housing has a stacking portion on which the sheet discharged from the discharge port is stacked. When viewed in the sheet width direction, the upper end of the intermediate portion is located above the upper surfaces of the first side plate and the second side plate and below the stacking portion. The image forming apparatus according to any one of Configurations 1 to 6, characterized in that.

[0143] (Configuration 8) The thickness of the frame member is thicker than the thickness of the first side plate and the thickness of the second side plate. The image forming apparatus according to any one of Configurations 1 to 7, characterized in that.

[0144] (Configuration 9) The image forming apparatus further includes an image processing unit that processes image information. The housing further has a case member to which the image processing unit is attached. A part of the case member protrudes above the upper surface of the second side plate. The case member is connected to each of the second side plate and the second support member. The image forming apparatus according to any one of Configurations 1 to 8, characterized in that.

[0145] (Configuration 10) The housing further includes a first extension member disposed above the first side plate and connected to the first side plate, and a second extension member disposed above the second side plate and connected to the second side plate. The case member is further connected to the second extension member. The image forming apparatus according to Configuration 9, characterized in that.

[0146] (Configuration 11) The housing further includes a first extension member disposed above the first side plate and connected to the first side plate, and a second extension member disposed above the second side plate and connected to the second side plate. The upper device is supported by the first extension member and the second extension member on the upstream side in the sheet discharge direction, and is supported by the first support member and the second support member on the downstream side in the sheet discharge direction. The image forming apparatus according to any one of Configurations 1 to 10, characterized in that.

[0147] (Configuration 12) At least one of the first support member and the second support member is connected to the upper surface of the upper device. The image forming apparatus according to any one of Configurations 1 to 11, characterized in that.

[0148] (Configuration 13) The upper device is a sheet processing device that receives a sheet on which an image is formed by the image forming means from the housing and performs processing on the sheet. The image forming apparatus according to any one of Claims 1 to 12, characterized in that.

[0149] (Configuration 14) The upper device is an image reading device that reads image information from a document. The image forming means forms an image on a sheet based on the image information read by the image reading device. The image forming apparatus according to any one of Configurations 1 to 12, characterized by the above.

Explanation of Signs

[0150] 100A... housing / 100B... image forming means (image forming section) / 140... first side plate (right side plate) / 141... second side plate (left side plate) / 145... frame member (front upper stay) / 145a... fourth surface (support member connection surface) / 145b... third surface (support member connection surface) / 145d... first and second surfaces (side plate connection surfaces) / 151... second support member (device support member left) / 200, 300... upper devices (sheet processing device, document reading device) / 260, 512... first support members (device support member right inner, device support member right)

Claims

1. A housing that houses an image forming unit for forming an image on a sheet, the housing having an outlet through which the sheet on which the image is formed by the image forming unit is discharged in the sheet discharge direction, an upper unit disposed above the housing, a first support member that supports the upper unit, a second support member that supports the upper unit, An image forming apparatus comprising: The housing has a first side plate extending in a direction intersecting the sheet width direction orthogonal to the sheet discharge direction, a second side plate extending in a direction intersecting the sheet width direction, a frame member disposed downstream of the outlet in the sheet discharge direction and connecting the first side plate and the second side plate, having In the sheet width direction, the first side plate and the first support member are disposed on a first side with respect to the center of the housing, and the second side plate and the second support member are disposed on a second side opposite to the first side with respect to the center of the housing. The frame member has a first surface connected to the first side plate, a second surface connected to the second side plate, a third surface connected to the first support member, and a fourth surface connected to the second support member. An image forming apparatus characterized by the above.

2. The housing has a stacking portion on which the sheet discharged from the outlet is stacked, The frame member is disposed at a position where the distance to the downstream end of the stacking portion in the sheet discharge direction is shorter than the distance to the upstream end of the stacking portion in the sheet discharge direction. The image forming apparatus according to claim 1, characterized by the above.

3. The first surface is connected to the upper surface of the first side plate, The second surface is connected to the upper surface of the second side plate, The third surface is connected to the first support member above the upper surface of the first side plate, The fourth surface is connected to the second support member above the upper surface of the second side plate. The image forming apparatus according to claim 1, characterized by the above.

4. The first surface, the second surface, the third surface, and the fourth surface are formed of a single metal plate, The metal plate is bent between the first surface and the third surface, and the metal plate is bent between the second surface and the third surface. The image forming apparatus according to claim 3, characterized by the above.

5. The frame member has a fifth surface extending in the sheet width direction and connecting the first surface and the second surface, and a sixth surface extending in the sheet width direction and connecting the third surface and the fourth surface. When viewed in the sheet width direction, the metal plate is bent between the fifth surface and the sixth surface. The image forming apparatus according to claim 4, characterized in that.

6. The frame member has an intermediate portion that extends in the sheet width direction and connects the first surface and the second surface. At least one of the upper end of the third surface and the upper end of the fourth surface is located above the upper end of the intermediate portion. The image forming apparatus according to claim 1, characterized in that.

7. The frame member has an intermediate portion that extends in the sheet width direction and connects the first surface and the second surface. The housing has a stacking portion on which the sheet discharged from the discharge port is stacked. When viewed in the sheet width direction, the upper end of the intermediate portion is located above the upper surfaces of the first side plate and the second side plate and below the stacking portion. The image forming apparatus according to claim 1, characterized in that.

8. The thickness of the frame member is thicker than the thickness of the first side plate and the thickness of the second side plate. The image forming apparatus according to claim 1, characterized in that.

9. The image forming apparatus further includes an image processing unit that processes image information. The housing further has a case member to which the image processing unit is attached. A part of the case member protrudes above the upper surface of the second side plate. The case member is connected to each of the second side plate and the second support member. The image forming apparatus according to claim 1, characterized in that.

10. The housing further has a first extension member disposed above the first side plate and connected to the first side plate, and a second extension member disposed above the second side plate and connected to the second side plate. The case member is further connected to the second extension member. The image forming apparatus according to claim 9, characterized in that.

11. The housing further has a first extension member disposed above the first side plate and connected to the first side plate, and a second extension member disposed above the second side plate and connected to the second side plate. The upper device is supported by the first extension member and the second extension member on the upstream side in the sheet discharge direction, and is supported by the first support member and the second support member on the downstream side in the sheet discharge direction. The image forming apparatus according to claim 1, characterized in that.

12. At least one of the first support member and the second support member is connected to the upper surface of the upper device. The image forming apparatus according to claim 1, characterized in that.

13. The upper device is a sheet processing device that receives a sheet on which an image has been formed by the image forming means from the housing and performs processing on the sheet. The image forming apparatus according to any one of claims 1 to 12, characterized in that.

14. The upper device is an image reading device that reads image information from a document, The image forming means forms an image on a sheet based on the image information read by the image reading device. The image forming apparatus according to any one of claims 1 to 12, characterized in that.

Images