Image forming apparatus

Abstract

To maintain maintainability.SOLUTION: An image forming apparatus comprises a frame and a unit that is supported by the frame, and is attachable to and detachable from the frame by being moved along an attaching / detaching direction intersecting a vertical direction. The frame includes a first column and a second column that are arranged with a spacing therebetween in a first direction intersecting the attaching / detaching direction and the vertical direction, and extend in the vertical direction. When the unit moves along the attaching / detaching direction, a lower end of a passing portion that passes through the position of the second column passes through a first height in the vertical direction. When the unit moves along the attaching / detaching direction, an upper end of the passing portion that passes through the position of the second column passes through a second height in the vertical direction. The second column includes a lower column portion and an upper column portion. An upper end of the lower column portion of the second column is located at a first position lower than the first height in the vertical direction, and a lower end of the upper column portion of the second column is located at a second position higher than the second height in the vertical direction. The first column includes a continuous portion that extends continuously in a region from at least the first height to the second height in the vertical direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus in which units can be detachably attached. [Background technology]

[0002] The industrial printing industry provides image forming devices such as large-format inkjet printers that are equipped with various units. The units are installed in a frame that forms the framework of the image forming device, and are attached so that they can be pulled out in front of the image forming device when viewed from the front. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-15865 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the frame, the space for installing the units is limited to a certain range depending on the function of each unit. Therefore, if the units are located behind the pillars that make up the frame when viewed from the front of the image forming apparatus, the units will interfere with the pillars of the frame when pulled out toward the image forming apparatus, making maintenance difficult.

[0005] On the other hand, it is possible to increase the size of the frame to expand the space in which the units are installed in order to realize an arrangement relationship according to the functions of the units, but this would result in an increase in the size of the image forming apparatus. [Means for solving the problem]

[0006] A typical configuration of the present invention comprises a frame body and a unit that is supported by the frame body and can be attached to and detached from the frame body by moving it along an attachment / detachment direction that intersects the vertical direction, wherein the frame body has a first pillar and a second pillar that are arranged at an interval in the attachment / detachment direction and a first direction that intersects the vertical direction, and each pillar extends vertically, wherein when the unit moves along the attachment / detachment direction, a lower end of a passing portion that passes through the position of the second pillar passes through a first height in the vertical direction, and when the unit moves along the attachment / detachment direction, an upper end of a passing portion that passes through the position of the second pillar passes through a second height in the vertical direction, the second pillar includes a lower pillar portion and an upper pillar portion, an upper end of the lower pillar portion of the second pillar is at a first position that is lower than the first height in the vertical direction, and a lower end of the upper pillar portion of the second pillar is at a second position that is higher than the second height in the vertical direction, and the first pillar includes a continuous portion that is continuous in the vertical direction at least in the region from the first height to the second height. [Effects of the Invention]

[0007] According to the present invention, the unit can be attached and detached without interfering with the pillars of the frame body, and maintainability can be maintained without increasing the size of the device. [Brief explanation of the drawings]

[0008] [Figure 1] Schematic cross-sectional view showing the general configuration of an image forming apparatus [Figure 2] Schematic cross-sectional view of the print belt unit [Figure 3] Perspective view of the frame [Figure 4] Front view of the frame [Figure 5] A perspective view of the lower frame of the frame body [Figure 6] (a)(b) Perspective view of the bottom plate of the lower frame of the frame body [Figure 7] (a)(b)(c) Schematic diagram of the connecting plate attached to the first column of the upper and lower frames [Figure 8] (a)(b) Schematic diagram of the lower frame assembly procedure [Figure 9]Diagram of the lower frame assembly procedure [Figure 10] A perspective view of the upper frame of the frame body [Figure 11] (a)(b) Schematic cross-sectional view of the image forming section of the print module [Figure 12] (a)(b)(c) Schematic diagram of assembly procedure for detachable parts [Figure 13] A perspective view of the mounting portion of the connecting metal plate DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of an image forming apparatus according to the present invention will be described below in detail with reference to the drawings. The dimensions, materials, and relative positions of the components of the image forming apparatus shown below do not limit the scope of the present invention unless otherwise specified. Components with the same reference numerals in the drawings have the same configuration or function, and redundant descriptions will be omitted where appropriate.

[0010] <Image forming device> The general configuration of an image forming apparatus will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing the configuration of an image forming apparatus. The image forming apparatus shown in Fig. 1 is an example of an inkjet image forming apparatus that forms images using an inkjet method.

[0011] In the image forming apparatus, paper (recording medium) fed from the paper feed module 1000 passes through the print module 2000, drying module 3000, fixing module 4000, cooling module 5000, inverting module 6000, and discharge stacking module 7000, in that order. The print module 2000 forms an image on the paper fed from the paper feed module 1000. The drying module 3000 reduces the liquid content of the ink to improve the fixation of the ink to the paper, and the fixing module 4000 heats the paper to soften the applied ink. The cooling module 5000 cools the fixed paper to solidify the softened ink and suppresses changes in paper temperature downstream of the cooling module. The inverting module 6000 orients the paper in the desired direction. The discharge stacking module 7000 aligns and stacks the printed paper.

[0012] During double-sided printing, the paper is U-turned and transported toward the print module by the cooling module 5000, and the front and back sides of the paper are reversed by the reversing device 4200 provided in the fixing module 4000. The paper then passes through the double-sided transport path of the drying module 3000 and paper feed module 1000 and is transported again to the print module 2000, where the back side is printed.

[0013] <Print Module> The configuration of the print module 2000 will be described with reference to Fig. 2. Fig. 2 is a schematic cross-sectional view of the print module 2000.

[0014] The print module 2000 is an image forming unit that performs recording processing on a conveyed sheet of paper (recording medium) from above using a recording head 10 to form an image on the paper. The print module 2000 has a pre-image registration correction unit 2400 (see FIG. 11(a)), a print belt unit 2200, and a recording unit 2300. The paper S is attracted and conveyed by the print belt unit 2200, ensuring clearance with the recording head 10.

[0015] The paper conveyed from the paper feed module 1000 has its tilt and position corrected by a pre-imaging registration correction unit 2400 (see FIG. 11(a)) before being conveyed to the print belt unit 2200. A recording unit 2300 is disposed opposite the print belt unit 2200 on the conveyance path. The recording unit 2300 performs recording (printing) on ​​the conveyed sheet (paper S) using a recording head 10 from above, forming an image on the paper. The print belt unit 2200 is disposed to transport the paper by suction and adsorbing it, ensuring stable paper transport behavior directly below the recording head 10. The paper S conveyed on the paper transport surface 26 of the print belt unit 2200 is conveyed with a clearance secured between the recording head 10 and the paper. The recording head 10 ejects ink onto the conveyed paper at a timing that allows it to form an image. The recording heads 10 are arranged in a row along the paper transport direction. In this example, in addition to the four colors of Y (yellow), M (magenta), C (cyan), and Bk (black), there are a total of five line-type recording heads corresponding to the reaction liquids.

[0016] The number of colors and recording heads in the image forming apparatus is not limited to 5. The inkjet method may be a method using a heat element, a method using a piezoelectric element, a method using an electrostatic element, a method using a MEMS element, or the like.

[0017] In this embodiment, the left-right direction refers to the sheet transport direction during image formation. The sheet transport direction is sometimes referred to as the first direction. Here, the upstream side of the transport direction of the paper S passing through the recording unit 2300 is defined as the right side, and the downstream side is defined as the left side. In this embodiment, the first direction refers to the left-right direction, and the first direction is a direction that intersects with the vertical direction. The vertical direction corresponds to the up-down direction of the image forming apparatus, and the upward direction in the vertical direction is defined as the up direction, and the downward direction is defined as the down direction. The direction in which the recording unit 2300 is pulled out from the print module 2000 is defined as the front direction, and the direction in which the recording unit 2300 is attached to the print module 2000 is defined as the rear direction. The front-to-rear direction is the attachment / detachment direction of a unit to / from the print module 2000, and is a second direction that intersects with the up-to-down direction (vertical direction) and the left-to-right direction (first direction). The defined front direction F, rear direction B, right direction R, left direction L, up direction U, and down direction D are shown in Figure 1, etc.

[0018] <Frame structure> Next, the frame that forms the framework of the image forming apparatus will be described with reference to Figures 3 and 4. Here, the frame of a print module will be used as an example of the frame. Figure 3 is a perspective view of the frame of the print module. Figure 4 is a front view of the frame of the print module.

[0019] The print module 2000 includes a frame 100 that supports a pre-image-creation registration correction section 2400, a recording section 2300, and a print belt unit 2200 as units.

[0020] Here, the units supported by the frame 100 are exemplified by a pre-imaging registration correction unit 2400, a recording unit 2300, and a print belt unit 2200. The print belt unit 2200 is a first transport unit that transports a sheet. The print belt unit 2200 is disposed below the recording unit 2300 in the vertical direction and facing the recording unit 2300. The recording unit 2300 is a recording unit that ejects ink onto a sheet to form an image. The pre-imaging registration correction unit 2400 is a second transport unit that transports a sheet toward the recording unit 2300. The pre-imaging registration correction unit 2400 is disposed between the print belt unit 2200 and the first pillar 101 in the left-right direction.

[0021] These units are supported so that they can be pulled out forward in the front-to-rear direction relative to the frame body 100, but this is not limiting. For example, the units may be supported so that they can be removed in the front-to-rear direction relative to the frame body 100, or any other configuration may be used as long as the units are supported so that they can be attached to and detached from the frame body 100.

[0022] The frame body 100 has a lower frame 200 as a lower frame body, and an upper frame 300 as an upper frame body vertically above the lower frame 200. The frame body 100 is formed by separately temporarily assembling and welding the lower frame 200 and the upper frame 300, and then combining them by placing the pillars of the upper frame 300 on the pillars of the lower frame 200. In other words, the upper frame 300 is connected to the vertically upper side of the lower frame 200.

[0023] As shown in FIG. 3, the frame body 100 has four pillars arranged at intervals in a first direction (left-right direction) that intersects the vertical direction, including a first pillar 101 that is the first pillar and a second pillar 102 that is the second pillar, each extending in the vertical direction.

[0024] Of the four pillars, the second pillar 102 is located on the left front side of the frame 100 and is discontinued in the vertical area where the print belt unit 2200 is attached and detached. That is, the second pillar 102 is not connected to the pillar in the area from altitude 1 to altitude 2 in the vertical direction from the ground (installation surface) as shown in FIG.

[0025] Furthermore, of the four pillars, the first pillars 101 other than the second pillar 102 are continuous in the vertical direction. That is, the first pillars 101 are connected in the region from altitude 1 to altitude 2. Of the first pillars 101, the first pillar 101 located on the front right side of the frame body 100 is the first pillar. Of the first pillars 101, the first pillar 101 located on the rear right side of the frame body 100 and the first pillar 101 located on the rear left side of the frame body 100 have the same configuration as the first pillar 101 located on the front right side of the frame body 100.

[0026] Here, altitude 1 is the height from the ground (installation surface) to a first position h1 in the vertical direction. Altitude 2 is the height from the ground (installation surface) to a second position h2 that is higher than the first position h1 in the vertical direction. The relationship between altitude 1 and altitude 2 is altitude 1<altitude 2.

[0027] The frame body 100 supports the recording unit 2300 as a unit between the first pillar 101 and the second pillar 102 in the left-right direction and between heights 1 and 2 in the vertical direction. The configurations of the lower frame 200 and upper frame 300 that make up the frame body 100 will be described below.

[0028] The first pillar 101 consists of a first lower pillar 1011 that is included in the lower frame 200 and extends upward to the second position h2, and a first upper pillar 1012 that is included in the upper frame 300 and extends upward from the second position h2, and is a pillar with no interruption in the area where the unit is attached and detached.

[0029] The second pillar 102 is composed of a second lower pillar 1021 included in the lower frame 200 and extending upward to the first position h1, and a second upper pillar 1022 included in the upper frame 300 and extending upward from the second position h2, and is a pillar with a discontinuity in the area where the unit is attached and detached.

[0030] <Bottom frame> As shown in Figure 5, the lower frame 200 has four lower columns 1011, 1021 standing at the four corners of the bottom plate 103, and the lower columns are connected by left side lower panel 1101, right side lower panel 1111, and rear side lower panel 1121, with a middle panel 104 placed on top of the bottom plate 103, creating a shelf-like structure. The front left lower column 1021 and rear left lower column 1011 are connected by the left side lower panel 1101, the front right lower column 1011 and rear right lower column 1011 are connected by the right side lower panel 1111, and the rear right lower column 1011 and rear left lower column 1011 are connected by the rear side lower panel 1121. Each element that makes up the lower frame 200 will be described below.

[0031] As shown in Fig. 6(a), the bottom plate 103 is attached by welding reinforcing beams 1032 into the space formed in a box shape by bending the edges of a flat plate 1031. Furthermore, as shown in Fig. 6(b), a lid 1033 is attached to the bottom plate 103 with screws so as to close the box-shaped space from above, thereby reinforcing its strength.

[0032] As shown in Figure 7(a), the lower column 1011 of the lower frame 200 is made by combining two U-shaped columns 10a and 10b, each bent into a U-shaped cross section, to form a square cross section. When assembling, the positions of the two U-shaped columns 10a and 10b are temporarily determined by driving rivets into appropriate positions, and then the columns are welded together to form the square-shaped lower column 1011, ensuring strength. The lower column 1021 is also constructed in the same way as the lower column 1011, although its vertical length (height) is different.

[0033] Of the four lower pillars 1011, 1021 erected on the lower frame 200, the first lower pillars 1011, 1021, which are located at the front right, rear right, and rear left of the device, excluding the second lower pillar 1021, have lower connecting plates 121 attached to their tops in a manner that covers the cross section as shown in Fig. 7(b). A crimped pin 122 is fixed to the lower connecting plate 121 so that it protrudes above the pillar.

[0034] Each lower pillar 1011, 1021 is connected by welding to the left lower plate 1101, the right lower plate 1111, and the rear lower plate 1121. A rear plate unit is formed by integrating the rear lower plate 1121 with two lower pillars 1011, a left plate unit is formed by integrating the left lower plate 1101 with one lower pillar 1021, and a right plate unit is formed by integrating the right lower plate 1111 with one lower pillar 1011.

[0035] The middle plate 104 has a structure similar to that of the bottom plate 103 except for the lid 1033, and has reinforcing beams attached by welding to the inside of the box-shaped flat plate with its edges bent.

[0036] Next, a procedure for assembling the above-mentioned elements into the lower frame 200 will be described with reference to Figures 8(a), 8(b), and 9. Figures 8(a), 8(b), and 9 are explanatory diagrams of the procedure for assembling the lower frame.

[0037] First, as shown in FIG. 8(a), the rear plate unit is erected on the bottom plate 103, and the bottom plate 103 and the rear plate unit are fixed with rivets. Then, as shown in FIG. 8(b), the left and right plate units are erected on the bottom plate 103, and the bottom plate 103 is fixed to the left and right side plate units, and the rear plate unit is fixed to the left and right side plate units, respectively, with rivets. This connects the bottom plate 103, the rear plate unit, the left plate unit, and the right plate unit to one another. Then, as shown in FIG. 9, the first lower column 1011 and the second lower column 1021 erected on the bottom plate 103 are fixed with screws, and the lower frame 200 is assembled. Then, the bottom plate 103, the rear plate unit, and the left and right side plate units fixed to one another with rivets are welded at appropriate positions to connect them together.

[0038] <Top frame> As shown in Figure 10, the upper frame 300 has a configuration in which a left upper plate 1102, a right upper plate 1112, and a rear upper plate 1122 are attached to four upper pillars 1012, 1022. The left upper plate 1102 is attached to the front left upper pillar 1022 and the rear left upper pillar 1012, the right upper plate 1112 is attached to the front right upper pillar 1012 and the rear right upper pillar 1012, and the rear upper plate 1122 is attached to the rear right upper pillar 1012 and the rear left upper pillar 1012. Each element that makes up the upper frame 300 will be described below.

[0039] The four upper pillars 1012, 1022 of the upper frame 300 are configured as square-shaped upper pillars 1012, 1022 by combining U-shaped pillars 10a, 10b, similar to the lower pillar 1011 of the lower frame 200 (see FIG. 7(a)).

[0040] Of the four upper columns 1012, 1022 of the upper frame 300, the first upper columns 1012, 1022, which are located at the front right, rear right, and rear left of the device, excluding the second upper column 1022, have upper connecting plates 123 attached to their lower ends in a manner that covers the cross section, as shown in Fig. 7(c). The upper connecting plate 123 has holes 124 that fit with pins 122 attached to the lower connecting plate 121 of the lower frame 200.

[0041] Each upper pillar 1012, 1022 is connected by welding to the left upper plate 1102, the right upper plate 1112, and the rear upper plate 1122. A rear plate unit is formed by integrating the rear upper plate 1122 with the two upper pillars 1012, a left plate unit is formed by integrating the left upper plate 1102 with one upper pillar 1022, and a right plate unit is formed by integrating the right upper plate 1112 with one lower pillar 1011.

[0042] Next, the procedure for assembling the above-mentioned elements into the upper frame 300 will be described.

[0043] When assembling the upper frame 300, the left and right plate units are rivet-fastened to the rear plate unit, similar to the lower frame 200. This connects the rear plate unit, left plate unit, and right plate unit to one another. Then, a horizontal pillar (beam) 127 configured similar to a square-shaped pillar is placed sideways on the upper surfaces of the pillar 1022 of the left plate unit and the pillar 1012 of the right plate unit. The horizontal pillar 127 is then rivet-fastened to the pillars 1022, 1012 of the left and right side plate units via L-shaped connecting metal plates 128. Then, the rear plate unit and the left and right side plate units that have been rivet-fastened to one another are welded together to secure and connect them.

[0044] <Combination of upper and lower frames> When the upper and lower frames are combined, pins 122 protruding from the tops of the pillars of the lower frame 200 fit into holes 124 in connecting plates 123 attached to the lower ends of the pillars of the upper frame 300. In other words, the frame body 100 is configured by connecting the upper frame 300 to the vertically upper side of the lower frame 200.

[0045] The shapes and configurations of the bottom plate 103, the square-shaped pillars, the middle plate 104, and the left and right rear side plates do not need to be configured as described above as long as they satisfy the required strength and functionality. Similarly, the configuration of each side plate unit and the assembly order of the frame body 100 are not limited to the procedure described above.

[0046] When the upper and lower frames are combined, pins 122 on the lower connecting plates 121 of the first lower columns 1011 located at the front right, rear right and rear left of the lower frame 200 fit into holes 124 on the upper connecting plates 123 of the first upper columns 1012 located at the front right, rear right and rear left of the upper frame 300, thereby forming a column 101 that is continuous in the vertical direction.

[0047] Furthermore, when the upper and lower frames are combined, the top of the second lower pillar 1021, which is located at the front left of the lower frame 200, faces the lower end of the second upper pillar 1022, which is located at the front left of the upper frame 300, leaving a gap between the first position h1 and the second position h2 for attaching and detaching the unit, thereby forming a pillar 102 that is interrupted in the vertical direction.

[0048] <Unit placement on the frame> 11(a) and 11(b), the arrangement of the units supported by the frame 100 will be described. Figures 11(a) and 11(b) are schematic cross-sectional views of the image forming section of the print module.

[0049] 11(a), in the frame 100, a print belt unit 2200 is installed on the middle plate 104 of the lower frame 200. The print belt unit 2200 can move on rails laid on the middle plate 104, and can be pulled out toward the front of the device for maintenance work.

[0050] In addition to the print belt unit 2200, a pre-imaging registration correction unit 2400 is also arranged on the intermediate plate 104. The pre-imaging registration correction unit 2400 is arranged upstream in the transport direction of the PBU 2200. During printing, the pre-imaging registration correction unit 2400 receives the paper S from the paper feed module 1000 (see FIG. 1) upstream in the transport direction relative to the print module 2000, corrects the paper S to a position that allows an image to be formed correctly, and then passes it to the print belt unit 2200, where the image is formed.

[0051] 11A, the left-right area on the intermediate plate 104 is occupied by the pre-imaging registration correction unit 2400 and the print belt unit 2200, which are arranged side by side in the transport direction. As a result, the print belt unit 2200 is positioned close to the downstream edge of the print module 2000 in the transport direction. This positioning also allows the print belt unit 2200 to function as a discharge unit that discharges sheets to the downstream module.

[0052] In this case, as shown in FIG. 11B, if a portion of the print belt unit 2200 is hidden behind the pillars of the frame 100 (shown by the dashed lines in the figure) when viewed from the front of the print module 2000, the print belt unit 2200 will interfere with the pillars of the frame 100 when pulled out toward the front of the device. One way to avoid this is to downsize the print belt unit 2200 and the pre-imaging registration correction unit 2400 so that they are not hidden behind the pillars. However, this would also require reducing the functionality of the print belt unit 2200 and the pre-imaging registration correction unit 2400, which could reduce their marketability. Furthermore, because the print belt unit 2200 would be spaced apart from the edge of the print module 2000 by the width of the pillars, it could be difficult to transfer sheets to downstream modules.

[0053] Therefore, the second pillars 102 constituting the frame 100 are configured so that they are discontinued in the region from the first position h1 to the second position h2. In other words, the second pillars 102 have two separate parts: a second lower pillar 1021 (lower pillar portion) and a second upper pillar 1022 (upper pillar portion). The second lower pillar 1021 extends upward in the vertical direction to the first position h1. In other words, the upper end of the second lower pillar 1021 is the first position h1. The second upper pillar 1022 extends upward from the second position h2. In other words, the lower end of the second upper pillar 1022 is the second position h2. The relationship between the first position h1 and the second position h2 and the portion of the print belt unit 2200 that passes through the position of the second pillars 102 when the print belt unit 2200 is attached or detached will be described below. As shown in FIG. 11B, when the print belt unit 2200 moves in the installation / removal direction, the lower end of the portion passing through the second pillar 102 passes through a first height H1. When the print belt unit 2200 moves in the installation / removal direction, the upper end of the portion passing through the second pillar 102 passes through a second height H2. The first position h1, which is the position of the upper end of the second lower pillar 1021, is lower than the first height H1 in the vertical direction. On the other hand, the second position h2, which is the position of the lower end of the second upper pillar 1022, is higher than the second height H2 in the vertical direction. In other words, the second pillar 102 has a discontinuity in the area through which the print belt unit 2200 passes when installing or removing the print belt unit 2200. This allows the print belt unit 2200 to be installed or removed without interfering with the pillars 102 of the frame 100, thereby preventing the device from becoming larger and maintaining ease of maintenance. On the other hand, the first pillar 101 includes a continuous portion that continues in the vertical direction from at least the first height H1 to the second height H2. In other words, the first pillar 101 is continuous at the height corresponding to the discontinued portion of the second pillar 102. This makes it possible to maintain the strength of the frame body.

[0054] <Detachable parts> As described above, the continuous first pillar 101 provides sufficient rigidity to the frame 100. However, if an unexpected force is applied, the second pillar 102 constituting the frame 100 may be partially broken and unable to withstand the load, causing the area of ​​the device at height 2 or higher to tilt. Therefore, except when the print belt unit 2200 is pulled out to the front of the device, the broken area of ​​the second pillar 102 (the area from the first position h1 to the second position h2) is connected, creating a continuous configuration similar to the first pillar 101, thereby improving robustness.

[0055] Therefore, the image forming apparatus according to this embodiment is provided with a detachable member 125 that can be attached to and detached from the second column 102, and the detachable member 125 is attached to an interrupted area of ​​the second column 102 except when the unit is being pulled out. In this embodiment, the detachable member 125 is located in an area where the print belt unit 2200 is attached and detached, between the second lower column 1021 and the second upper column 1022 of the second column 102, and is connected to the second lower column 1021 and the second upper column 1022.

[0056] 12(a) to 12(c) will be used to explain the configuration of the detachable member 125 and the attachment and detachment of the reinforcing block 1251 and the reinforcing metal plate 1252 that constitute the detachable member 125. Figures 12(a), 12(b), and 12(c) are explanatory diagrams of the assembly procedure for the detachable member 125.

[0057] The detachable member 125 is composed of a reinforcing block 1251 which is a first detachable member, and a reinforcing metal plate 1252 which is a second detachable member. The reinforcing block 1251 is connected to the reinforcing metal plate 1252 and the second upper column 1022. The reinforcing metal plate 1252 is connected to the reinforcing block 1251 and the second lower column 1021. This will be explained below.

[0058] First, as shown in Figure 12(a), the upper part of the reinforcement block 1251 is placed inside the second pillar 1022 of the upper frame 300 so that it fits inside the pillar. Then, screws are fastened from the outside of the pillar to secure the reinforcement block 1251 and the second pillar 1022 together, as shown in Figure 12(b). Then, as shown in Figure 12(c), the reinforcement sheet metal 1252 is fastened with screws to the reinforcement block 1251 and the second pillar 1021 of the lower frame 200. In this way, the reinforcement block 1251 and the reinforcement sheet metal 1252 that make up the detachable member 125 connect the discontinued regions of the second pillars 102 of the upper frame 300 and the lower frame 200.

[0059] On the other hand, when removing the detachable member 125, the above steps can be followed in reverse order.

[0060] In this embodiment, the detachable member 125 is configured as two separate parts, but this configuration is not limited to this. For example, the detachable member 125 may be configured as one piece, or as three or more separate parts, as long as it is configured to be detachably attached to the second column 102 and to connect the disconnected areas of the second column 102 above and below. Furthermore, the method and procedure for attaching the detachable member 125 to the second column 102 are not limited to those described above.

[0061] <Connection metal plate> After the detachable member 125 is removed from the second pillar 102, there is a risk that the weight of the upper frame 300 may cause the upper frame 300 to fall toward the second upper pillar 1022 during maintenance.

[0062] Therefore, the image forming apparatus according to this embodiment includes a connecting metal plate 126 as a connecting member that connects the second lower pillar 1021 and the second upper pillar 1022 outside the area where the print belt unit 2200 is attached and detached in the left-right direction.

[0063] The connecting metal plate 126 will be described with reference to Fig. 13. Fig. 13 is a perspective view of the mounting portion of the connecting metal plate.

[0064] The connecting metal plate 126 straddles the second lower column 1021 and the second upper column 1022 and is attached to the outer side surface of each column so as not to interfere when pulling out the print belt unit 2200. That is, the connecting metal plate 126, which is a connecting member, connects the second lower column 1021 and the second upper column 1022 outside the area in which the detachable member 125 is arranged in the left-right direction, as shown in Fig. 13. Therefore, the connecting metal plate 126 can connect the second lower column 1021 and the second upper column 1022 even when the detachable member 125 is attached between the second lower column 1021 and the second upper column 1022.

[0065] The connecting metal plate 126 is fixed to the second lower column 1021 by welding at weld point m, and to the second upper column 1022 by using a small metal plate 1261 with a caulking shaft and pins and screws. The connecting metal plate 126 must be made of a material and thickness that will not buckle even when subjected to the load of the upper frame 300. However, since it is installed on the frame 100, which forms the skeleton of the image forming apparatus, adding bending or other means to increase rigidity would result in the outer shape of the apparatus expanding accordingly. This would make it difficult to load the apparatus into an elevator when transporting it, and would increase the risk of damage from collisions. For this reason, the connecting metal plate 126 is made of a flat plate, and its strength is guaranteed only by its thickness, width, and material. However, this does not apply if the product size is sufficiently small and a complex shape does not have much of an impact.

[0066] In this embodiment, the connecting metal plate 126 is fixed to the second column 102 using pins, screws, and welding, but this was selected from the perspective of the required part precision and cost, and is not generally limited to this method.

[0067] Next, detailed calculations used to determine the shape of the connecting metal plate 126 to prevent buckling will be described.

[0068] The load received by the connecting metal plate 126 is approximately the combined weight of the upper frame 300, the exterior weight, and the total weight of the built-in units. In this embodiment, this is assumed to be approximately 200 kg, and when the load N applied to each pillar is set to 50 kg, the shape and material of the connecting metal plate 126 are determined so that the buckling load P exceeds the load N. Equation 1 is used to calculate the buckling load P.

[0069] (Formula 1) P=n(π 2 EI) / I 2

[0070] As described above, in this embodiment, the shape of the connecting metal plate 126 is a flat plate, so the second moment of area I is calculated as follows.

[0071] (Formula 2) I=(bh 3 ) / 12

[0072] In the above formula, the coefficient n is determined by the support form of the metal plate, and since it is supported at both ends, the calculation is done with n=4.

[0073] In this embodiment, the connecting metal plate 126 is made of SUS and is 5.0 mm thick, 50 mm wide, and 138.2 mm long, resulting in a buckling load P of 207.8 kg. In this case, 207.8 (= buckling load P) > 50 (= load N), ensuring a safety factor of approximately 4.0. However, this calculation only assumes a static load and is not sufficient to withstand unexpected shocks that may occur during logistics or equipment operation. Therefore, the detachable member 125 must be attached except during maintenance.

[0074] Based on the above calculations, by adding a connecting metal plate 126 that can withstand the load during maintenance, etc., it becomes possible to safely pull out the print belt unit 2200 simply by removing the detachable member 125 .

[0075] In this example, the connecting metal plate 126 achieved the above results, but the required shape, dimensions, and materials will naturally differ depending on the size of the device and differences in rigidity due to differences in the frame structure, so the results are not limited to these.

[0076] As described above, according to this embodiment, the print belt unit 2200 can be attached and detached without interfering with the second pillar 102 of the frame body 100, and maintainability can be maintained without increasing the size of the device. [Explanation of symbols]

[0077] S...Paper (sheet) h1…1st position h2…2nd position H1...First height H2...Second height 100…Frame 101 ... First Pillar (1st Pillar) 102 ...Second Pillar (2nd Pillar) 103…Bottom plate 121 ...Under the connection plate 122...pin 123 ...on the connection plate 124...holes 125 ... Detachable member 126 ...Connecting metal plate (connecting member) 127…Horizontal pillar 128...Connecting sheet metal 200...Bottom frame (bottom frame body) 300...Upper frame (upper frame body) 1011…1st lower pillar 1012 ... First upper pillar 1021…Second lower pillar 1022 ...Second upper pillar 1031...flat plate 1032 ... Reinforcing beam 1033 …lid 1101...Left side board bottom 1102...On the left side board 1111…Under the right side plate 1112...on the right side board 1121…under the back plate 1122...on the rear plate 1251 ... Reinforcement block (first detachable member) 1252 ... Reinforcement plate (second detachable member) 2000...print module 2200 ... Print belt unit (unit, first conveying unit) 2300...Recording unit (unit) 2400 ... Pre-imaging registration correction unit (unit, second conveying unit)

Claims

1. A frame body, a unit supported by the frame body and detachable from the frame body by moving the unit along an attachment / detachment direction that intersects with the vertical direction; the frame body has a first pillar and a second pillar that are arranged at an interval in a first direction that intersects the attachment / detachment direction and a vertical direction, and each of the first pillar and the second pillar extends in the vertical direction; when the unit moves in the attachment / detachment direction, a lower end of a passing portion that passes through the position of the second pillar passes through a first height in the vertical direction, when the unit moves in the attachment / detachment direction, an upper end of a passing portion that passes through the position of the second pillar passes through a second height in the vertical direction, the second pillar includes a lower pillar portion and an upper pillar portion; an upper end of the lower pillar portion of the second pillar is at a first position that is lower than the first height in the vertical direction; a lower end of the upper pillar portion of the second pillar is at a second position that is higher than the second height in the vertical direction; The first pillar includes a continuous portion that is continuous in a region from the first height to the second height in the vertical direction. An image forming apparatus characterized by:

2. the second pillar includes a detachable member that can be attached to and detached from the upper pillar portion and the lower pillar portion, The detachable member is disposed in an area through which the unit passes when it moves along the attachment / detachment direction, and is connected to the lower pillar portion and the upper pillar portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. the detachable member includes a first detachable member and a second detachable member, the first detachable member is connected to the second detachable member and the upper pillar portion; The second detachable member is connected to the first detachable member and the lower pillar portion.

3. The image forming apparatus according to claim 2, wherein the image forming apparatus is a recording medium.

4. the second pillar includes a connecting member connecting the upper pillar portion and the lower pillar portion, the connecting member is disposed outside an area through which the unit passes when the unit moves along the attachment / detachment direction; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

5. the second pillar includes a connecting member connecting the upper pillar portion and the lower pillar portion, the connecting member is disposed outside an area through which the unit passes when the unit moves along the attachment / detachment direction; 3. The image forming apparatus according to claim 2, wherein the image forming apparatus is a recording medium.

6. the detachable member is made of a metal plate including a bent portion, The connecting member is configured in a flat plate shape.

6. The image forming apparatus according to claim 5,

7. 2. The image forming apparatus according to claim 1, wherein the unit comprises a conveying section for conveying a sheet.

8. The unit includes a first transport unit that transports a sheet, a recording unit that ejects ink onto the sheet to form an image, and a second transport unit that transports the sheet toward the recording unit, the second transport unit is disposed between the first transport unit and the first pillar in the first direction and is supported by the frame body; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. the image forming apparatus is configured by a plurality of modules including at least a first module and a second module connected to the downstream side of the first module in a sheet conveying direction, the frame is included in the first module, The unit includes a discharge section that discharges the sheet from the first module to transport the sheet to the second module.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

Images