Image forming apparatus

Abstract

To provide an image forming apparatus that facilitates connection of an interface cable connecting to an external device to a connector part without increasing the size of an electrical unit.SOLUTION: In an electrical unit 70, a step part is formed between a first holding part 201a and a second holding part 201b, and connector parts 701 are provided on a center partition plate 202 that forms the step part. The formation of the step part between the first holding part 201a and the second holding part 201b can secure a space on the back side of the first holding part 201a. The center partition plate 202 faces the space, and a relay substrate 71 having the connector part 701 mounted thereon is held on the second holding part 201b so that the connector part 701 is exposed to the space from the center partition plate 202. This configuration enables the interface cable to be detachably attached to the connector part 701 with the use of the space secured on the back side of the first holding part 201a, and facilitates connection of the interface cable to the connector part 701 without increasing the size of the electrical unit 70.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to an image forming apparatus such as a printer, a copier, a facsimile machine or a multifunction machine.

Background Art

[0002] In an image forming apparatus, a plurality of units for forming an image on a recording material are provided in the apparatus main body. The image forming apparatus includes, for example, a main control board for controlling the entire image forming apparatus, a drive control board for controlling a motor or the like, a high voltage board for controlling various voltages for charging, developing or transferring, and an electrical wiring board such as an interface board for inputting and outputting signals to and from external devices. These electrical wiring boards are housed in a box-shaped electrical unit. Further, the electrical unit is provided with a connector portion on the side surface to which an interface cable can be connected in order to connect an external device and the interface board (Patent Document 1).

[0003] In an image forming apparatus, for example, a process unit having a photosensitive drum or a developing device is provided so as to be detachable from the front side of the housing when a user performs regular replacement, cleaning or jam processing. On the other hand, the electrical unit housing the electrical wiring board is arranged on the back side of the housing so that a user using the image forming apparatus does not accidentally access it and does not interfere when the process unit is detached or attached.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Recently, image forming machines for commercial printing that can form toner images on more recording materials in a shorter time are being used. Compared to home-use image forming machines, these machines use larger components such as power supply equipment and process units, resulting in a larger overall size, including the housing. However, there is a demand for further miniaturization even in image forming machines for commercial printing. One possible solution is to place a bottle housing unit containing toner bottles filled with replenishment toner on the top surface of the housing, and then place the aforementioned electrical unit in the remaining space on the top surface where the bottle housing unit is located. However, in such a case, it has been desirable to be able to easily connect the interface cable to the connector part without increasing the size of the electrical unit, but such a solution has not yet been proposed.

[0006] In view of the above problems, the present invention aims to provide an image forming apparatus that, when the bottle storage unit and the electrical unit are arranged in parallel adjacent to each other on the top surface of the housing, facilitates the connection of interface cables for connecting to external equipment to the connector portion without increasing the size of the electrical unit. [Means for solving the problem]

[0007] An image forming apparatus according to one embodiment of the present invention is an image forming apparatus for forming an image on a recording material, comprising a housing, a bottle housing unit provided on the top surface of the housing and housing a toner bottle filled with replenishment toner, The bottle storage unit is arranged adjacent to the bottle storage unit in the left-right direction. It has a first electrical circuit board, a second electrical circuit board capable of inputting and outputting signals between it and an external device connected to an interface cable, and a connector section to which the interface cable can be connected, and on the top surface adjacent to the bottle storage unit left and right The system comprises an electrical unit arranged in parallel in the direction, and the second electrical circuit board is the left and right With respect to direction, the first electrical circuit board is located further away from the bottle housing unit than the first electrical circuit board, and the left and right perpendicular to the direction Front and back Regarding the direction, the first electrical circuit board From the rear The connector is positioned in an offset location, and is provided on the bottle housing unit side of the second electrical circuit board. [Effects of the Invention]

[0008] According to the present invention, when a bottle storage unit and an electrical unit housing a second electrical circuit board capable of inputting and outputting signals to and from external devices are arranged in parallel adjacent to each other on the top surface of the housing, the interface cable can be easily connected to the connector without increasing the size of the electrical unit. [Brief explanation of the drawing]

[0009] [Figure 1] A perspective view showing an image forming system equipped with the image forming apparatus of this embodiment. [Figure 2] A schematic diagram showing the image formation system. [Figure 3] A control block diagram illustrating the electrical unit. [Figure 4] A perspective view showing an image forming and transfer apparatus. [Figure 5] A perspective view showing the image forming and transfer apparatus with the unit cover removed. [Figure 6] External perspective view showing the electrical unit. [Figure 7] A perspective view showing the electrical unit with the left and right covers removed. [Figure 8] A perspective view showing the electrical unit with the left cover, right cover, and relay board removed. [Modes for carrying out the invention]

[0010] <Image Forming System> First, the image forming system equipped with the image forming apparatus of this embodiment will be described using Figures 1 and 2. As shown in Figure 1, the image forming system 1 comprises an image forming apparatus 2 and a recording material loading device 3 capable of loading recording material S discharged from the image forming apparatus 2. The image forming apparatus 2 is an electrophotographic tandem full-color printer, and in this embodiment, it is divided into an image forming transfer apparatus 500 and a fixing and transport apparatus 600. The image forming transfer apparatus 500 and the fixing and transport apparatus 600, and the fixing and transport apparatus 600 and the recording material loading device 3 are each connected in a manner that allows for the transfer of recording material (sheets). Examples of recording material include paper such as plain paper, cardboard, rough paper, textured paper, and coated paper, as well as plastic film and cloth.

[0011] A bottle storage unit 20 is positioned on the top surface 1a of the image forming transfer apparatus 500. An electrical unit 70 is positioned in the remaining space on the top surface 1a where the bottle storage unit 20 is located, and an operating unit 80 is positioned in the remaining space. The electrical unit 70 is positioned adjacent to the bottle storage unit 20 in the left-right direction, and both the electrical unit 70 and the bottle storage unit 20 are covered by a unit cover 120.

[0012] The operation unit 80 is positioned in front of the electrical unit 70 such that a display (such as an LCD touch panel 82) capable of displaying various information and keys for inputting various information according to user operation are located on the front side. The operation unit 80 is connected to the electrical unit 70 via a signal cable 90 so that it can receive power and input / output signals, and an external device 101 such as a personal computer is connected via an interface cable 104 so that it can input / output signals. Note that the operation unit 80 is not limited to being located to the left of the illustrated bottle storage unit 20, but may be movably provided so that it can be placed in other positions on the top surface 1a or on the top surface 1c of the fixing and conveying device 600.

[0013] On the other hand, the top surface 1c of the fixing and conveying device 600 is formed in a flat shape so that a recording material can be placed thereon as a work space for a user to check an image formed on the recording material or to sort the recording materials. Since the top surface 1c of the fixing and conveying device 600 is wide, for example, an original reading device (not shown) capable of reading an original may be placed thereon.

[0014] In this specification, when a user operates the operation unit 80, the side on which the user stands is referred to as "front (or forward)", and the opposite side is referred to as "back (or rear)". Also, the left side when viewed from the front is referred to as "left", and the right side when viewed from the front is referred to as "right".

[0015] Also, here, an example in which the recording material loading device 3 is connected to the image forming apparatus 2 is shown, but the present invention is not limited thereto, and a post-processing device that performs various post-processing operations on the recording material on which the toner image is fixed may be connected to the image forming apparatus 2. As the post-processing device, for example, one or a plurality of devices that perform various post-processing operations such as an inserter, a puncher, a binding machine, a folding machine, a finisher, a trimmer, etc. may be combined and connected. Thus, in the image forming system 1 shown in FIG. 1, in order to be able to output in-line a recording material as a product obtained by performing various post-processing operations on various materials, various post-processing devices are selectively connected to the image forming apparatus 2.

[0016] In the present embodiment, the housing 500A of the image forming and transferring device 500 and the housing 600A of the fixing and conveying device 600 are formed separately, and are made movable by a plurality of casters provided respectively. Thereby, even if the image forming and transferring device 500 or the fixing and conveying device 600 is large, it is possible to perform packing and transportation separately in a state where the housing 500A and the housing 600A are separated, and the workability until installation is improved.

[0017] The image forming and transferring device 500 will be described. As shown in FIG. 2, inside the housing 500A of the image forming and transferring device 500, a sheet feeding unit 30, an image forming unit 40, a part of a sheet conveying unit 50, etc. are arranged.

[0018] The sheet feeding unit 30 is located at the bottom of the housing 500A and has a cassette 31 for loading and storing the recording material S and a feeding roller 32, and feeds the recording material S toward the image forming unit 40. The sheet transport unit 50 is provided to be able to transfer the recording material S across housing 500A and housing 600A. The sheet transport unit 50 has a secondary transfer transport path 51, a pre-fixing transport path 52, a discharge path 53, and a re-transport path 54, and transports the recording material S fed from the sheet feeding unit 30 between the image forming transfer apparatus 500 and the fixing transport apparatus 600.

[0019] The image forming unit 40 forms a toner image on the recording material S according to image data received from an unillustrated document reader or external device 101. The image forming unit 40 has image forming sections 41y, 41m, 41c, and 41k, and an intermediate transfer unit 44, which form a toner image on the recording material S. The image forming sections 41y to 41k are process units that form yellow, magenta, cyan, and black toner images, respectively, and are each detachably mounted on the housing 500A.

[0020] The intermediate transfer unit 44 has multiple rollers, including primary transfer rollers 44y, 44m, 44c, 44k, a drive roller 44a, a tension roller 44d, and a secondary transfer inner roller 45a, and an intermediate transfer belt 44b wrapped around these rollers. The primary transfer rollers 44y to 44k are positioned opposite the photosensitive drums 47y to 47k, respectively, and are in contact with the intermediate transfer belt 44b. By applying a primary transfer voltage to the primary transfer rollers 44y to 44k using a power supply (not shown), the toner images formed on the photosensitive drums 47y to 47k are sequentially transferred to the intermediate transfer belt 44b.

[0021] The image forming units 41y to 41k are arranged in a line along the direction of movement of the intermediate transfer belt 44b. The intermediate transfer belt 44b is stretched over multiple rollers (44a, 44d, 45a) and rotated. The intermediate transfer belt 44b then carries and transports the toner image that is to be primary transferred as described later. A secondary transfer outer roller 45b is positioned opposite the secondary transfer inner roller 45a, which stretches the intermediate transfer belt 44b, and forms a secondary transfer unit T2 that transfers the toner image on the intermediate transfer belt 44b to the recording material S.

[0022] The image forming units 41y to 41k are substantially identical in configuration except for the difference in the toner image development color. Therefore, the yellow image forming unit 41y will be described as a representative example, and the other image forming units 41m, 41c, and 41k will not be described.

[0023] The image forming unit 41y is equipped with a cylindrical photosensitive drum 47y as a photoreceptor. The photosensitive drum 47y is rotationally driven by a motor (not shown). Around the photosensitive drum 47y are a charging roller 48y, an exposure unit 43y, a developer unit 49y, and a primary transfer roller 44y.

[0024] When the image formation operation begins, the surface of the rotating photosensitive drum 47y is uniformly charged by the charging roller 48y. Next, the photosensitive drum 47y is scanned and exposed by laser light corresponding to the image data emitted from the exposure unit 43y. This forms an electrostatic latent image on the surface of the photosensitive drum 47y corresponding to the image data. The electrostatic latent image formed on the photosensitive drum 47y is developed into a toner image by a developer containing toner and carrier housed in the developer unit 49y. Toner is supplied to the developer unit 49y from a toner bottle 42y filled with replenishment toner. The toner bottle 42y and toner bottles of other colors 42m to 42k are detachably housed in parallel in the left-right direction within the bottle housing unit 20.

[0025] The toner image formed on the photosensitive drum 47y is transferred to the intermediate transfer belt 44b in a primary transfer section, which consists of the drum and the primary transfer roller 44y positioned on either side of the intermediate transfer belt 44b. At this time, a primary transfer voltage is applied to the primary transfer roller 44y. After the primary transfer, any toner remaining on the surface of the photosensitive drum 47y is removed by a drum cleaning blade (not shown).

[0026] This process is performed sequentially in the yellow, magenta, cyan, and black image forming units 41y to 41k, superimposing the four toner images on the intermediate transfer belt 44b. Subsequently, the recording material S is transported to the secondary transfer unit T2 in accordance with the toner image formation timing. Then, by applying a secondary transfer voltage to the secondary transfer outer roller 45b, the full-color toner image formed on the intermediate transfer belt 44b is transferred to the recording material S all at once. Any toner remaining on the intermediate transfer belt 44b after the secondary transfer is removed by a belt cleaning device (not shown).

[0027] The recording material S onto which the toner image has been transferred is transported from the image forming transfer apparatus 500 to the fixing and transport apparatus 600. The fixing unit 46 and part of the sheet transport unit 50 are arranged inside the housing 600A of the fixing and transport apparatus 600. The fixing unit 46 has a fixing roller 46a heated by a heater (not shown) and a pressure roller 46b that pressurizes the recording material S against the fixing roller 46a. The recording material S on which the toner image has been formed, transported from the image forming transfer apparatus 500, is heated and pressurized while being held and transported in the fixing nip section formed by the fixing roller 46a and the pressure roller 46b. As a result, the toner image is fixed to the recording material S.

[0028] The recording material S, heated by the fuser 46, is transported by the sheet discharge unit 60. The sheet discharge unit 60 has a pair of discharge rollers 61 arranged in the discharge path 53 and a discharge port 62 formed in the housing 600A. The pair of discharge rollers 61 transports the recording material S transported in the discharge path 53 toward the discharge port 62. The discharge port 62 is formed so that the recording material S can be transferred to the recording material loading device 3 connected to the housing 600A.

[0029] The image forming apparatus 2 of this embodiment is capable of forming images on both sides of the recording material S. In the case of single-sided printing, the recording material S with the fixed toner image is transported to the discharge path 53 and discharged outside the housing 600A from the discharge port 62. In the case of double-sided printing, the recording material S with the fixed toner image is transported to the re-transport path 54. In the re-transport path 54, the recording material S is inverted by a switchback operation, and the front and back sides of the recording material S are swapped. The inverted recording material S is returned to the housing 500A, passes through the pre-secondary transfer transport path 51, and is transported to the secondary transfer section T2 with the unprinted back side facing the intermediate transfer belt 44b. In the secondary transfer section T2, the full-color toner image formed on the intermediate transfer belt 44b is transferred to the back side of the recording material S all at once. After that, the toner image of the recording material S is fixed by the fuser 46 and transported to the discharge path 53 and discharged outside the housing 600A from the discharge port 62.

[0030] Figure 3 is a control block diagram showing a part of the control performed by the electrical unit 70. As shown in Figure 3, in this embodiment, the electrical unit 70 has electrical boards such as a relay board 71, a main control board 72, and an exposure control board 73, and a storage device 74 such as a solid-state drive or a hard disk drive (SSD, HDD). The electrical board is a board on which components such as a CPU, memory, electronic components, electrical components, and connectors are mounted. In addition to those shown, the electrical unit 70 may also be connected to a developing board that controls the developing units 49y to 49k, but these are not relevant to the main point of the invention, so their illustration and description are omitted here.

[0031] The main control board 72 includes, for example, a CPU 75, a ROM (Read Only Memory) 76 that stores various programs, a RAM (Random Access Memory) 77 that temporarily stores data, and an input / output circuit (I / F) 78 that inputs and outputs signals. The storage device 74 is a removable, high-capacity storage device for storing data, mainly image processing programs and digital image data.

[0032] The CPU (Central Processing Unit) 75 is a microprocessor that controls the entire image forming system 1 and is the main component of the main control board 72. The CPU 75 can read image processing programs and digital image data from the storage device 74 and perform image formation on the recording material S in accordance with the execution of the image processing program. The CPU 75 is connected via input / output circuits 78 to the exposure control board 73 for controlling the exposure units 43y~43k (see Figure 2), a relay board 71 such as an interface board for inputting and outputting signals to and from external devices 101, the storage device 74, the operation unit 80, and so on.

[0033] The operation unit 80 includes a driver board 81 and a liquid crystal touch panel 82. The liquid crystal touch panel 82 can display various information for the user to operate the image forming apparatus 2, such as messages notifying the remaining amount of recording material in the cassette 31 and the remaining amount of toner in the developer units 49y~49k, as well as warning messages and replenishment procedures for when these consumables are depleted. The liquid crystal touch panel 82 can also accept various inputs related to image formation by the user, such as the size and basis weight of the recording material S, the image density, and the number of prints. The driver board 81 is an electrical board that controls the power supplied from the power supply 12 to the liquid crystal touch panel 82 in order to enable the liquid crystal touch panel 82 to perform the above-mentioned display and input acceptance.

[0034] The control unit 80 is connected to the electrical unit 70 by a signal cable 90. The signal cable 90 consists of a signal line 90a and a power line 90b, and may be a bundle of signal line 90a and power line 90b, or it may be separate signal line 90a and power line 90b. Signal line 90a connects the input / output circuit 76 of the main control board 72 to the driver board 81, and power line 90b connects the power supply 12 to the driver board 81. The power supply 12 is provided separately from the electrical unit 70 and is located on the back of the housing 500A or inside the housing 500A.

[0035] The relay board 71 is electrically connected to the input / output circuit 78 of the main control board 72, and is also electrically connected to the external device 101 via an interface cable 104. The external device 101 has an external controller 102 and an external display 103, and the main control board 72 can control the external controller 102 via the relay board 71. By controlling the external controller 102, the main control board 72 can, for example, display the various information described above on the external display 103, or send and receive various data such as image data with the external device 101.

[0036] Next, the arrangement of the bottle storage unit 20 and the electrical unit 70 in the image forming transfer apparatus 500 will be explained using Figures 4 and 5 with reference to Figure 1. Figure 4 is a perspective view showing the image forming transfer apparatus 500, and Figure 5 is a perspective view showing the image forming transfer apparatus 500 with the unit cover 120 removed. As described above, the bottle storage unit 20 and the electrical unit 70 are arranged on the top surface 1a of the image forming transfer apparatus 500, and the bottle storage unit 20 and the electrical unit 70 are covered by the unit cover 120. The unit cover 120 is composed of multiple covers combined together.

[0037] In this embodiment, the bottle unit cover 120a of the unit cover 120 is rotatable and can be opened and closed, and when the bottle unit cover 120a is opened, the bottle storage unit 20 is exposed. In addition, the electrical unit cover 120b of the unit cover 120 is removable by screws, and when the electrical unit cover 120b is removed, the electrical unit 70 is exposed. That is, the user can access the bottle storage unit 20 by opening the bottle unit cover 120a and attach and detach toner bottles 42y to 42k to the bottle storage unit 20. The user can access the electrical unit 70 by removing the electrical unit cover 120b and attach and detach the interface cable 104 and signal cable 90 to the connector portion 701 of the electrical unit 70 (see Figures 7 and 8 described later).

[0038] As shown in Figure 5, a bottle storage unit 20 is mounted on the top surface 1a of the housing 500A. The bottle storage unit 20 is fixed to the housing 500A with screws (not shown) so that the stored toner bottles 42y to 42m are arranged in the left-right direction. An electrical unit 70 is also mounted on the top surface 1a of the housing 500a. The electrical unit 70 is mounted adjacent to the bottle storage unit 20 in the left-right direction (first direction), which is the same direction as the arrangement of the toner bottles 42y to 42m within the bottle storage unit 20. The electrical unit 70 is also fixed to the housing 500a with screws (not shown) in the same way as the bottle storage unit 20.

[0039] The electrical unit 70 is connected to a signal cable 90 for power supply and signal input / output with the operation unit 80, and to an interface cable 104 for signal input / output with an external device 101 such as a personal computer. In this embodiment, as will be described in detail later, the electrical unit 70 has a connector section 701 for connecting the interface cable 104 at a location further away from the bottle storage unit 20 than the right end 70a on the bottle storage unit 20 side, in the left-right direction. The connector section 701 is designed so that the interface cable 104 can be connected by inserting it straight in from the bottle storage unit 20 side towards the left. As the connector section 701, for example, a right-angle type USB connector, an HDMI® connector, a DisplayPort connector, or any other type corresponding to the interface cable 104 to be connected can be used. The electrical unit 70 also has another connector section 702 for connecting the signal cable 90 at the left end 70b on the opposite side of the bottle storage unit 20, in the left-right direction.

[0040] <Electrical Unit> Next, the detailed configuration of the electrical unit 70 of this embodiment will be described with reference to Figure 5 and Figures 6 to 8. Figure 6 is an external perspective view showing the electrical unit 70. Figure 7 is a perspective view showing the electrical unit 70 with the left cover 203 and right cover 204 removed. Figure 8 is a perspective view showing the electrical unit 70 with the left cover 203, right cover 204, and the relay board 71 removed.

[0041] As shown in Figure 6, the electrical unit 70 has a housing composed of an electrical circuit board holder 201, a central partition plate 202, a left cover 203, and a right cover 204, and multiple electrical circuit boards are held within the housing, as will be described in more detail later. In this embodiment, the left cover 203 is detachably fastened with screws or the like so as to cover the left side of the electrical circuit board holder 201, with the central partition plate 202 located in the center in the left-right direction as the boundary, and the right cover 204 is detachably fastened with screws or the like so as to cover the right side of the electrical circuit board holder 201. The electrical circuit board holder 201 has a stepped shape in which the left cover 203 and the right cover 204 are positioned offset from each other in the front-rear direction, and the central partition plate 202 is formed to connect the left cover 203 and the right cover 204. In this way, in the electrical unit 70, a stepped space M is secured on the rear side of the right cover 204, the size of which is determined by the left-right length of the right cover 204 and the front-rear height of the central partition plate 202.

[0042] As shown in Figure 7, in the electrical unit 70, the electrical circuit board holder 201 is broadly divided into a first holder 201a and a second holder 201b, which is formed in parallel to the first holder 201a in the left-right direction, separated by a central partition plate 202. The first holder 201a holds the exposure control board 73 as the first electrical circuit board, and the right cover 204 is attached to it (see Figure 6).

[0043] On the other hand, the second holding part 201b holds the relay board 71 as the second electrical circuit board, and the left cover 203 is attached to it (see Figure 6). In this embodiment, the relay board 71 is equipped with multiple (two in this case) connector parts 701 as connectors for board-to-wire connection. Multiple (two in this case) openings 202a are formed in the central partition plate 202, and the relay board 71 is held by the second holding part 201b such that the connector parts 701 are exposed through the openings 202a of the central partition plate 202. Thus, the relay board 71 is positioned further from the bottle housing unit 20 than the exposure control board 73 in the left-right direction, and offset from the exposure control board 73 in the front-rear direction (the second direction perpendicular to the first direction). The connector parts 701 are provided on the bottle housing unit side (right side in this case) of the relay board 71. In other words, the connector parts 701 are positioned within the projection plane of the electrical circuit unit 70 in the front-rear direction.

[0044] In other words, the central partition plate 202 (second opposing surface) facing the bottle storage unit 20 is located further from the bottle storage unit 20 in the left-right direction than the right end 70a (first opposing surface) of the first holding part 201a facing the bottle storage unit 20, and protrudes further than the right end 70a in the front-rear direction, forming a step between the first holding part 201a and the second holding part 201b. The connector part 701 is provided on the central partition plate 202 that forms the step, and the interface cable 104 can be attached to and detached from the connector part 701 using the stepped space M (see Figure 6) secured on the rear side of the first holding part 201a.

[0045] As shown in Figures 7 and 8, the second holding section 201b holds the main control board 72 and the storage device 74 in addition to the relay board 71. The main control board 72, which is the third electrical board, is stacked and positioned in a location aligned with the exposure control board 73 in the left-right direction and overlapping with the relay board 71 in the front-back direction. The storage device 74 is positioned above the main control board 72. In this way, the main control board 72 and the storage device 74 are held in the second holding section 201b so as to overlap with the relay board 71 on the projection plane on the front side of the relay board 71.

[0046] As described above, in this embodiment, a stepped portion is formed between the first holding portion 201a and the second holding portion 201b in the electrical unit 70, and the connector portion 701 is provided on the central partition plate 202 that forms the stepped portion. By forming a stepped portion between the first holding portion 201a and the second holding portion 201b, a stepped space M is secured on the rear side of the first holding portion 201a. The central partition plate 202 faces the stepped space M, and the connector portion 701 is exposed from the central partition plate 202 towards the stepped space M. In this manner, the relay board 71 on which the connector portion 701 is mounted is held in the second holding portion 201b. This allows the interface cable 104 to be attached to and detached from the connector portion 701 using the stepped space M secured on the rear side of the first holding portion 201a. Therefore, it is possible to easily connect the interface cable 104 that connects to the external device 101 to the connector portion 701 without increasing the size of the electrical unit 70.

[0047] Furthermore, it is preferable that the electrical unit cover 120b be made of metal. This is because covering the electrical unit 70 with a metal electrical unit cover 120b prevents the image forming and transfer apparatus 500 from malfunctioning due to noise or static electricity generated from the circuit boards held within the electrical unit 70 or the signal lines connecting those circuit boards. [Explanation of Symbols]

[0048] 1a...Top surface, 2...Image forming apparatus, 20...Bottle storage unit, 42y (42m~42k)...Toner bottle, 70...Electrical unit, 70a...First opposing surface (right end), 71...Second electrical circuit board (relay board), 72...Third electrical circuit board (main control board), 73...First electrical circuit board (exposure control board), 80...Operation section, 90...Cable (signal cable), 101...External equipment, 104...Interface cable, 201a...First holding section, 201b...Second holding section, 202...Second opposing surface (stepped section, central partition plate), 500A...Housing, 701...Connector section, 702...Another connector section, S...Recording material

Claims

1. An image forming apparatus for forming an image on a recording material, The casing and A bottle storage unit is provided on the top surface of the aforementioned housing and houses a toner bottle filled with replacement toner, The electrical unit comprises a first electrical circuit board arranged adjacent to the bottle storage unit in the left-right direction, a second electrical circuit board capable of inputting and outputting signals to and from an external device connected to an interface cable, and a connector portion to which the interface cable can be connected, and is arranged in parallel in the left-right direction adjacent to the bottle storage unit on the top surface. The second electrical circuit board is positioned further away from the bottle storage unit than the first electrical circuit board in the left-right direction, and positioned rearward from the first electrical circuit board in the front-rear direction perpendicular to the left-right direction. The connector portion is provided on the bottle housing unit side of the second electrical circuit board. An image forming apparatus characterized by the following features.

2. The electrical unit has a third electrical circuit board that is stacked and positioned in a location adjacent to the first electrical circuit board in the left-right direction and overlapping with the second electrical circuit board in the front-rear direction. The image forming apparatus according to feature 1.

3. The second electrical circuit board is an interface board that controls the input and output of signals to the external device connected via the interface cable. The image forming apparatus according to feature 2.

4. The third electrical circuit board is the main control board that controls the entire image forming apparatus. The image forming apparatus according to feature 2 or 3.

5. The electrical unit has a first holding portion for holding the first electrical circuit board, and a second holding portion formed in parallel with the first holding portion in the left-right direction for holding the second electrical circuit board and the third electrical circuit board. The second holding portion has a second opposing surface facing the bottle storage unit that, in the left-right direction, is further from the bottle storage unit than the first opposing surface of the first holding portion facing the bottle storage unit, and in the front-rear direction, protrudes further rearward than the first opposing surface, thereby forming a stepped portion with the first holding portion. The connector portion is provided in the stepped portion. The image forming apparatus according to any one of claims 2 to 4.

6. A separate unit for operating the image forming apparatus is provided in addition to the housing, The third electrical circuit board and the operating unit are connected by a cable capable of inputting and outputting signals, The second holding portion is provided with another connector portion on the end opposite to the stepped portion that is away from the bottle storage unit in the left-right direction, to which the cable can be connected. The image forming apparatus according to feature 5.

7. The stepped portion is provided in the central part of the electrical unit in the left-right direction. The image forming apparatus according to claim 5 or 6.

Images