Image forming device

Abstract

To provide an image forming apparatus that effectively uses a space in the apparatus and can be reduced in size.SOLUTION: An image forming apparatus of the present invention has: an image forming unit that forms an image on a recording medium; a first frame and a second frame that are arranged to sandwich the image forming apparatus therebetween and support the image forming unit; an exterior member that covers the first frame, the exterior member extending along a surface of the first frame; and an electronic circuit board that is provided on the opposite side of the image forming unit with the surface of the first frame therebetween and is arranged between the first frame and the exterior member. The electronic circuit board extends in a direction intersecting with a surface of the exterior member.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an electrophotographic image forming apparatus for forming and fixing an image on a recording medium. [Background technology]

[0002] Image forming devices such as laser printers and copiers are configured with an image forming section that forms an image and transfers it to a recording medium, a supply section where a recording medium is placed and supplied to the image forming section, and a fixing section that fixes the image. The image forming section, supply section, and fixing section each have a drive section that is composed of a drive source, a drive transmission member, a drive member, etc., and a power supply board and a control board are provided to operate these. Conventionally, electronic circuit boards such as the power supply board and the control board have often been disposed between a frame that supports the image forming section, supply section, fixing section, etc., and an exterior that covers the outside of the device. For example, a configuration has been proposed in which the power supply board is disposed parallel to the transport path without increasing the size of the device (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-84734 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the electronic circuit board is arranged parallel to the transport path, the workability may be impaired when the transport path is opened to clear a jam. In addition, an exterior member is arranged on the outside of each of the pair of side frames, and the electronic circuit board is arranged between the side frame and the exterior member. A drive unit for driving the image forming unit is attached to one of the pair of side frames on the same surface as the electronic circuit board. The drive unit is large in size due to its complex mechanism, especially in color machines, and there is not enough space to arrange the electronic circuit board. Therefore, the electronic circuit board is arranged next to the drive unit, and the space below the drive unit is not fully utilized. [Means for solving the problem]

[0005] In order to solve the above problems, an image forming apparatus according to the present invention includes an image forming unit that forms an image on a recording medium, a first frame and a second frame that are arranged to sandwich the image forming unit and support the image forming unit, an exterior member that covers the first frame, the exterior member extending along a surface of the first frame, and an electronic circuit board that is provided on the opposite side of the surface of the first frame from the image forming unit and is arranged between the first frame and the exterior member; A drive unit having a motor; The electronic circuit board Mounting surface extends in a direction intersecting the surface of the exterior member the mounting surface extends in a direction intersecting with a surface of the first frame, the drive unit is provided on the opposite side of the surface of the first frame from the image forming unit, and is disposed between the first frame and the exterior member, the drive unit and a first end of the electronic circuit board overlap when viewed from a direction perpendicular to the surface of the exterior member, and the electronic circuit board is disposed at an angle so that the first end is away from the drive unit. It is characterized by the fact that Effect of the Invention

[0006] According to the present invention, it is possible to provide an image forming apparatus that can be made compact by effectively utilizing the space inside the apparatus. [Brief description of the drawings]

[0007] [Figure 1] 1 is a cross-sectional view illustrating an image forming process of an image forming apparatus according to a first embodiment; [Diagram 2] FIG. 1 is a perspective view of an image forming apparatus according to a first embodiment; [Diagram 3]FIG. 1 is a side view illustrating the inside of an exterior member according to a first embodiment; [Figure 4] FIG. 1 is a cross-sectional view illustrating the arrangement of a power supply unit according to a first embodiment; [Diagram 5] FIG. 1 is an exploded perspective view illustrating a configuration of a power supply unit according to a first embodiment; [Figure 6] FIG. 1 is a side view illustrating the installation of a power supply unit according to the first embodiment; [Figure 7] FIG. 1 is a perspective view illustrating the attachment of a power supply unit according to a first embodiment; [Figure 8] FIG. 1 is a cross-sectional view illustrating an airflow configuration according to a first embodiment. [Figure 9] FIG. 11 is a side view of an image forming apparatus according to a second embodiment. [Figure 10] FIG. 11 is a side view illustrating the arrangement of the power supply unit according to the second embodiment; [Figure 11] FIG. 11 is a cross-sectional view illustrating the arrangement of a power supply unit according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Example 1 A first embodiment of the present invention will be described below.

[0009] (Image forming device) FIG. 1 is a schematic diagram illustrating a color laser printer as an example of an image forming apparatus 100. The image forming apparatus 100 has a configuration in which a cartridge door 100a is rotated and opened, and then a cartridge support portion 100b supporting a plurality of cartridges 105 is pulled out from inside the image forming apparatus 100 to the outside, thereby making it possible to replace the cartridges 105. In the following description, the surface of the image forming apparatus 100 on which the cartridge door 100a is provided is defined as the front surface, the surface facing the front surface is defined as the rear surface, and the direction in which the front surface and the rear surface face each other is defined as the front-rear direction. When the image forming apparatus 100 is viewed from the direction facing the front surface, the side surface located on the right is defined as the right side surface, and the side surface located on the left is defined as the left side surface. The description will be given assuming that the up-down direction perpendicular to the horizontal plane defined by the front-rear direction and the left-right direction is defined as the vertical direction.

[0010] The image forming apparatus 100 includes an image forming unit 101, a recording medium supply unit 102, and a fixing unit 103. The image forming unit 101 includes a laser scanner 104, a cartridge 105, an intermediate transfer belt 106, and a secondary transfer roller 107. The laser scanner 104 is configured to be able to irradiate the cartridge 105 with laser light.

[0011] Each cartridge 105 includes a toner container 108 that contains toner, a photosensitive drum 109 onto which laser light is irradiated from the laser scanner 104, a charging roller 110 that charges the photosensitive drum 109, and a developing roller 111 that adheres the toner to the photosensitive drum 109. The cartridges 105 contain yellow, magenta, cyan, and black toner, respectively. The four cartridges 105 are disposed vertically below the laser scanner 104.

[0012] The intermediate transfer belt 106 is disposed vertically below the four cartridges 105. The intermediate transfer belt 106 is an endless belt. A belt drive roller 112, a primary transfer roller 113, and a tension roller 114 are provided on the inner side of the intermediate transfer belt 106 and support the intermediate transfer belt 106. The intermediate transfer belt 106 is rotatable by tension applied by the tension roller 114 and a driving force transmitted from the belt drive roller 112. Four primary transfer rollers 113 are provided and each of them is in contact with the photosensitive drums 109 of the four cartridges 105 with a predetermined pressure, with the intermediate transfer belt 106 sandwiched therebetween. The secondary transfer roller 107 is disposed so as to face the belt drive roller 112 via the intermediate transfer belt 106, and is in contact with the intermediate transfer belt 106 with a predetermined pressure.

[0013] The recording medium supply unit 102 is composed of a storage tray 115, a supply roller 116, a separation unit 117, and a conveyance unit 118. The storage tray 115 is a storage unit capable of stacking the recording medium P, and is configured to be detachable from the image forming apparatus 100 by pulling it forward. The storage tray 115 is provided with a lift plate 119, and is provided so as to be capable of rising and falling according to the number of stacked recording media P. The supply roller 116 is provided at a position facing the storage tray 115 with the stacked recording media P sandwiched therebetween. The separation unit 117 is located downstream of the supply roller 116, is provided on a conveyance guide 120, and is composed of a conveyance roller 121 and a separation roller 122. The conveyance roller 121 and the separation roller 122 are each provided with a rubber member on their surfaces. The separation roller 122 is provided with a torque limiter built in, and is configured to generate a predetermined load torque. The separation roller 122 contacts the conveying roller 121 with a predetermined pressure, and when the conveying roller 121 is driven, the conveying roller 121 is driven while generating a predetermined load torque. The conveying section 118 is provided downstream of the separation section 117 and upstream of the nip portion of the secondary transfer roller 107, and is composed of a registration pair 123 and a shutter member 124. The shutter member 124 is configured to be rotatable with a predetermined load, and is disposed upstream of the nip portion of the registration pair 123. The fixing section 103 is composed of a fixing roller 125, a heat pressing member 126, and a discharge roller pair 127. The fixing roller 125 is disposed downstream of the secondary transfer roller 107, and the heat pressing member 126 contacts the fixing roller 125 with a predetermined pressure. The heat pressing member 126 has a heat generating member 128 inside. The discharge roller pair 127 is provided downstream of the fixing roller 125.

[0014] (Image formation operation) The image forming apparatus 100 starts a printing operation when a print signal is input. The four photoconductor drums 109 start rotating, and the laser scanner 104 irradiates the surfaces of the four photoconductor drums 109 with laser light in accordance with image information to be printed. The surfaces of the photoconductor drums 109 are charged by the charging rollers 110, and an electrostatic latent image is formed in accordance with the irradiated laser light. The electrostatic latent image on the surface of the photoconductor drum 109 is supplied with toner by the developing roller 111, and is developed into a toner image. The toner image on the surface of the photoconductor drum 109 is transferred to the intermediate transfer belt 106 by a voltage applied to the primary transfer roller 113. The intermediate transfer belt 106 is driven by the belt drive roller 112 to transport the toner image to a nip portion with the secondary transfer roller 107 while receiving the toner image transferred from each cartridge 105. In parallel with the above operation, in the recording medium supply unit 102, the supply roller 116 conveys the recording medium P stacked on the storage tray 115 to the separation unit 117. When a plurality of recording media P are conveyed to the separation unit 117, only one recording medium P is separated at the nip by the load torque of the separation roller 122 and conveyed to the conveyance unit 118. In the conveyance unit 118, the leading edge of the recording medium P abuts against the shutter member 124. Since the shutter member 124 is provided with a predetermined rotation load, the recording medium P forms a loop by the conveyance force of the separation unit 117, pushes aside the shutter member 124, and enters the nip of the registration pair 123. Here, if the recording medium P is skewed, the leading edge of the recording medium P that abuts obliquely due to the formation of the loop becomes straight against the shutter member 124, and is held by the registration pair 123 to correct the skew. The recording medium P that has passed through the registration pair 123 is conveyed to a nip portion formed between a secondary transfer roller 107 and a belt drive roller 112 while the conveying speed is controlled, and the toner image conveyed by the intermediate transfer belt 106 is transferred onto the recording medium P. The recording medium P onto which the toner image has been transferred is conveyed to a contact portion between a fixing roller 125 and a heat pressing member 126. The recording medium P is pressurized and heated, so that the toner melts and is fixed onto the surface. Thereafter, the recording medium P is discharged outside the apparatus by a discharge roller pair 127, and is sequentially stacked on a discharge tray 129 provided on the top surface of the apparatus.

[0015] (Exterior materials) FIG. 2 is a perspective view of the image forming apparatus 100. An exterior member 130 is disposed on the side (right side) of the image forming apparatus 100. The exterior member 130 is provided with a handle 132, a louver 131, and an inlet opening 133. The handle 132 (recess) is formed on the exterior member 130 near the center in the front-rear direction of the image forming apparatus 100 such that a portion connected to the bottom surface of the image forming apparatus 100 is recessed inside the image forming apparatus 100. Although not shown in the figure, a handle is also disposed on the exterior member 130 on the opposite side of the image forming apparatus 100 in the same manner, so that the image forming apparatus 100 can be lifted by hooking fingers on the handle 132 from both sides of the image forming apparatus 100. The position of the handle 132 is disposed in consideration of the center of gravity of the image forming apparatus 100, so that the posture of the apparatus is stable when lifted. The multiple louvers 131 are provided on both sides of the handle 132 in the front-rear direction of the image forming apparatus 100, and serve as openings for drawing air into the inside of the apparatus. The inlet opening 133 allows a power cord to be inserted, and is provided on the rear surface of the exterior member 130 adjacent to and perpendicular to the side surface on which the handle 132 and the louvers 131 are provided. The inlet opening 133 is formed so that an inlet 134 provided in a power supply unit 138, which will be described later, is exposed from the inside. The image forming apparatus 100 is supplied with power by connecting a power cord connected to a commercial power source to the inlet 134.

[0016] 3 is a side view showing the inside of exterior member 130, and exterior member 130, louvers 131, and handle 132 are indicated by dashed lines. FIG 4 is a cross-sectional view showing power supply unit 138 along the AA cross-sectional line in FIG 3.

[0017] The exterior member 130 is disposed at a position facing the side frame 135 so as to cover the side frame 135, and an image forming drive unit 141 is attached to the side frame 135 between them. Here, the side frame 135 is a plate-shaped frame made of metal or resin that forms a part of the frame of the image forming apparatus 100, and supports the right end of the photosensitive drum 109 of the image forming unit 101 including the cartridge 105 in the direction of the rotation axis. Note that another side frame (not shown) is provided at a position facing the side frame 135 across the image forming unit 101, and this side frame (not shown) supports the left end of the photosensitive drum 109 of the image forming unit 101 in the direction of the rotation axis. The side frame 135 and the side frame (not shown) are disposed so as to sandwich the image forming unit 101. The image forming drive unit 141 for driving the image forming unit 101 and the power supply unit 138 are attached to the side frame 135.

[0018] The image formation drive unit 141 includes an image formation drive frame 139 and a motor 140 as a drive source, as well as a drive transmission member (not shown) made of a gear or the like inside the image formation drive frame 139, and is capable of transmitting the drive force of the motor 140 to the image forming section 101. As described below, an air duct 137 is attached to the image formation drive frame 139, and a fan 142 is installed above the air duct 137. On the other hand, the power supply unit 138 includes a power supply board 144 which is an electronic circuit board, and a board holding member 145.

[0019] (Power supply unit configuration) Next, the configuration of the power supply unit 138 will be described. FIG. 5 is an exploded perspective view showing the configuration of the power supply unit 138. The power supply unit 138 is composed of a power supply board 144, a board holding member 145, an inlet 134, and an inlet holding member 146. The board holding member 145 is made of sheet metal and has a plurality of board holding surfaces 147 for mounting the power supply board 144. The power supply board 144 is fastened to the board holding member 145 at a plurality of points with screws 148, some of which serve as earths. The board holding member 145 also suppresses the influence of magnetism from the outside, and covers almost the entire surface of the power supply board 144 to prevent noise from being generated in the power supply board 144. The board holding member 145 has a bent portion so that one end (rear of the image forming apparatus 100) is perpendicular to the board holding surface 147, and the inlet holding member 146 is attached to the bent portion. The inlet holding member 146 is capable of holding the inlet 134. The inlet 134 is electrically connected to the power supply board 144, and has a role of supplying power to the inside of the image forming apparatus 100 by inserting a power cord connected to a commercial power source. The power supply board 144 has various electronic circuit elements 149 arranged thereon, and converts AC current input from the outside into DC current and reduces the voltage to a predetermined voltage value. The power supply board 144 includes electronic circuit elements 149 that generate heat and a connector 150 for connecting a motor board, and the electronic circuit elements 149 that generate heat need to be cooled by airflow. As mounting surfaces for mounting the power supply unit 138 to the image forming apparatus 100, a first mounting surface 151 is provided on the board holding member 145, and a second mounting surface 152 is provided on the inlet holding member 146. The first mounting surface 151 is provided at the other end (the front of the image forming apparatus 100) opposite to the end where the inlet holding member 146 is attached.

[0020] (Power supply unit layout) FIG. 6 is a side view showing a first mounting surface 151 when the power supply unit 138 is attached to the apparatus, and FIG. 7 is a perspective view showing a second mounting surface 152 when the power supply unit 138 is attached to the apparatus. The board holding member 145 has a board holding surface 147 for holding the power supply board 144, and a first mounting surface 151 for mounting the power supply unit 138 to a power supply mounting member 153 provided on the image forming drive frame 139 or the side frame 135. The board holding surface 147 is configured to support the power supply board 144 by fastening the power supply board 144 with a screw 148. The first mounting surface 151 is fastened to the power supply mounting member 153 with the screw 148, and the power supply unit 138 is fixed to the side frame 135 via the image forming drive frame 139, or directly to the side frame 135. In this manner, the power supply unit 138 is attached to the side frame 135.

[0021] In this embodiment, board holding member 145 has board holding surface 147 inclined at a predetermined angle with respect to first mounting surface 151. In other words, board holding surface 147 intersects with first mounting surface 151. As a result, when power supply unit 138 is attached to image forming apparatus 100 with first mounting surface 151 extending in the vertical direction, power supply board 144 can be held in an inclined position with respect to side frame 135 extending in the vertical direction.

[0022] That is, even if the handle 132 is provided on the exterior member 130 so that the portion connected to the bottom surface of the image forming apparatus 100 is recessed inside the image forming apparatus 100, interference between the power supply board 144 and the handle 132 can be prevented. Furthermore, the lower end of the power supply board 144 can be disposed between the image formation drive frame 139 and the side frame 135 in the vertical direction, and the power supply board 144 can be disposed below the image formation drive frame 139. Therefore, when viewed from the direction from the exterior member 130 toward the side frame 135 (when viewed from the direction perpendicular to the surface of the exterior member 130), the lower end 155 is disposed so as to appear to overlap with the handle 132. That is, the lower end 155 of the power supply board 144 is located between the side frame 135 and the handle 132 in the left-right direction. In this way, power supply board 144 is arranged at an angle so that distance L1 between upper end 154 and the side frame is greater than distance L2 between lower end 155 and the side frame (L1>L2). Power supply board 144 extends in a direction intersecting the surface of exterior member 130, and is desirably positioned and inclined so that the lower side of board holding member 145 and handle 132 are close to each other, and the upper side of board holding member 145 and exterior member 130 are close to each other.

[0023] Thus, the vertical distance H1 from the bottom surface 160 of the image forming apparatus 100 to the image forming drive frame 139 is smaller than the length H2 of the power supply substrate 144 in a cross-section extending in the vertical direction (H1 < H2). Therefore, the upper end portion 154 of the power supply substrate 144 is positioned between the image forming drive frame 139 and the exterior member 130, and is arranged such that when viewed from the direction from the exterior member 130 toward the side frame 135, the upper end portion 154 appears to overlap with the image forming drive frame 139. In the vertical direction, in the case of a configuration where the power supply substrate 144 is arranged vertically above the handle 132 and below the image forming drive frame 139, the height W from the upper end of the handle 132 to the lower end of the image forming drive frame 139 needs to be equal to or greater than the length H2 of the power supply substrate 144. As a result, it becomes difficult to miniaturize the image forming apparatus 100. However, in this embodiment, in the vertical direction, the height W from the upper end of the handle 132 to the lower end of the image forming drive frame 139 can be made smaller than the length H2 or more of the power supply substrate 144, and thus the image forming apparatus 100 can be miniaturized.

[0024] In the configuration of this embodiment, since the power supply board 144 is inclined with respect to the vertical direction, the electronic circuit element 149 near the image formation drive frame 139 approaches the image formation drive frame 139. Therefore, the electronic circuit element 149 that is high from the board surface of the power supply board 144 may collide with the image formation drive frame 139. Therefore, the electronic circuit element 149 that is high from the board surface is arranged according to the distance between the power supply board 144 and the image formation drive frame 139 and the distance between the power supply board 144 and the side frame 135. In other words, the electronic circuit element 149 that is high from the board surface is arranged vertically below the image formation drive frame 139 and close to the image formation drive frame 139. In other words, the electronic circuit element 149 is arranged so that the height of the electronic circuit element 149 from the board surface increases from the upper end 154 of the power supply board 144 to the lower end 155 of the power supply board 144. In this way, it is possible to install electronic circuit elements 149 that are tall from the substrate surface even when power supply substrate 144 is tilted. Also, by arranging power supply substrate 144 at an angle, the weight of electronic circuit elements 149 acts in the holding direction of substrate holding member 145, so that the effects of vibrations and the like can be reduced and power supply substrate 144 can be held stably.

[0025] Here, examples of electronic circuit elements 149 that are high above the board surface include a low-voltage power transformer, a heat sink, and an electrolytic capacitor. The electrolytic capacitor plays a role in smoothing the AC voltage supplied from an external power source via the inlet 134. The low-voltage power transformer plays a role in stepping down the input voltage that has been smoothed by the electrolytic capacitor and converted back into an AC voltage by the switching element. The heat sink is provided to dissipate heat from the power supply board 144.

[0026] As described above, the end of the substrate holding member 145 is provided with a bent portion perpendicular to the substrate holding surface 147, and the inlet holding member 146 is attached to this bent portion. The inlet holding member 146 has a second attachment surface 152, and the inlet holding member 146 is attached to the bent portion of the substrate holding member 145 at the second attachment surface 152. Then, as shown in FIG. 7, the second attachment surface 152 of the inlet holding member 146 is fastened to the side frame 135 with a screw 148 from the rear of the image forming apparatus 100, so that the substrate holding member 145 can be attached to the side frame 135. The first attachment surface 151 and the second attachment surface 152 are grounded by fastening them with the screw 148 to at least one of the side frame 135 and the image forming drive frame 139, which are made of sheet metal at least at one place each.

[0027] (Airflow configuration) Next, the airflow configuration will be described. FIG. 8 shows the configuration of the air passage that forms the airflow, and is a cross-sectional view taken along the CC line in FIG. 3. The airflow is provided to cool the heat-generating electronic circuit element 149 that is disposed on the power supply board 144. As shown in FIG. 2, the exterior member 130 is provided with louvers 131 on both sides of the handle 132 in the front-rear direction of the image forming apparatus 100. The image forming drive frame 139 is provided with an air duct 137, and a fan 142 is provided vertically above the air duct 137. The arrows in the figure indicate the flow of the airflow. When the fan 142 operates, it starts to suck in air on the power supply board 144 side. Then, air enters the inside of the device through the louvers 131 provided on the exterior member 130, generating an airflow. The airflow flows around the board holding member 145 and flows to the mounting surface on which the electronic circuit element 149 of the power supply board 144 is mounted. The power supply board 144 forms an air passage between the mounting surface and the side frame 135 located opposite to the mounting surface, and between the power supply board 144 and the image formation drive frame 139. Vertically above the power supply board 144, the image formation drive frame 139, the air duct 137, and the exterior member 130 form an air passage to the fan 142. The airflow passes between the electronic circuit elements 149 and flows from the lower side to the upper side of the power supply board 144, and removes heat from the electronic circuit elements 149 that generate heat during the flow, thereby cooling them. Thereafter, the airflow flows through the air passage formed by the air duct 137 and the exterior member 130, and is sucked into the fan 142. The air sucked into the fan 142 passes through the inside of the image forming apparatus 100, cools the fixing unit 103 and the cartridges 105, and is then discharged to the outside of the image forming apparatus 100.

[0028] In this embodiment, in order to cool the heat-generating electronic circuit elements 149 on the power supply board 144, the power supply board 144 and the image formation drive frame 139 are arranged at a predetermined distance B, and an air passage is formed between the power supply board 144 and the image formation drive frame 139. The air taken in through the air duct 137 is narrow in space between the upper end 154 of the power supply board 144, and therefore the upper end of the board holding member 145, and the exterior member 130. Therefore, the air flows around the ends of the power supply board 144 and the board holding member 145 in the front-rear direction of the image forming apparatus 100. As a result, the air flows from the surface opposite to the mounting surface of the power supply board 144 toward the mounting surface, cools the electronic circuit elements 149 on the mounting surface, and is then sucked into the fan 142 through the space between the power supply board 144 and the image formation drive frame 139.

[0029] According to the configuration of this embodiment described above, when viewed from the direction from the exterior member 130 toward the side frame 135 (direction perpendicular to the surface of the exterior member 130), the upper end 154 of the power supply board 144 overlaps with the image formation drive frame 139. When viewed from the direction from the exterior member 130 toward the side frame 135 (direction perpendicular to the surface of the exterior member 130), the lower end 155 of the power supply board 144 overlaps with the handle 132. As a result, by arranging the power supply board 144 at an angle so that the distance L1 between the upper end 154 and the side frame 135 is larger than the distance L2 between the lower end 155 and the side frame 135 (L1>L2), it is possible to effectively utilize space and reduce the size of the device.

[0030] Example 2 A second embodiment of the present invention will be described below. Descriptions of configurations similar to those of the first embodiment will be omitted. Fig. 9 is a side view showing an image forming apparatus 100 in the second embodiment. The first embodiment is configured such that the power supply board 144 is inclined relative to the vertical direction, but the second embodiment is different in that the power supply board 144 is inclined relative to the front-rear direction.

[0031] In this embodiment, the exterior member 130 arranged on the side of the image forming apparatus 100 is provided with a louver 131 as an opening for sucking air into the machine in front of the image forming apparatus 100. FIG. 10 is a side view showing a state in which the exterior member 130 is removed. Here, a supply drive unit 162 is attached to a side frame 135. The supply drive unit 162 has a supply motor 163 as a drive source for driving the supply roller 116 and the registration pair 123 in a supply drive frame 164, and further, a drive transmission member such as a gear (not shown) is provided inside the supply drive frame 164. The power supply board 144 is attached to the side frame 135 and the supply drive frame 164 via board attachment members 169 at the four corners.

[0032] FIG. 11 shows a state where the power supply board 144 is attached to the apparatus, and is a cross-sectional view taken along the cutting plane line D-D in FIG. 9. A supply drive frame 164 is attached to the side frame 135, and a louver 131 (recess) is provided on the exterior member 130 so as to protrude inside the apparatus. The supply drive frame 164 and the louver 131 are arranged apart from each other with a predetermined distance G provided in the front-rear direction of the image forming apparatus 100. The distance H3 in the front-rear direction of the image forming apparatus 100 from the supply drive frame 164 to the front surface 170 of the exterior member 130 is smaller than the length H4 of the power supply board 144 in the cross-section extending in the front-rear direction of the image forming apparatus 100 (H3 < H4). Therefore, the rear end portion 167 is arranged to be positioned between the supply drive frame 164 and the exterior member 130. The electronic circuit element 149 arranged on the power supply board 144 is arranged on the board surface facing the exterior member 130 side in order to be cooled by the air flow from the louver 131. Here, the power supply board 144 is inclined and arranged at a position closer to the side frame 135 so that the distance L3 between the rear end portion 167 and the side frame 135 is larger than the distance L4 between the front end portion 168 and the side frame 135 (L3 > L4). The power supply board 144 extends in a direction intersecting the exterior member 130, and it is desirable that the front end portion 168 is close to the side frame 135 and the power supply board 144 and the supply drive frame 164 are inclined to be in a close position. Further, the electronic circuit elements 149 are arranged such that there are an electronic circuit element 149 with a high height from the board surface and an electronic circuit element 149 with a low height from the board surface according to the distances between the power supply board 144, the louver 131, and the exterior member 130. That is, the electronic circuit element 149 with a low height from the board surface is arranged on the supply motor 163 side, and the electronic circuit element 149 with a high height from the board surface is arranged on the front surface 170 side of the exterior member 130. Even when the power supply board 144 is inclined in this way, it is possible to install the large-sized electronic circuit element 149.

[0033] According to the configuration of this embodiment described above, when viewed from the direction from the exterior member 130 toward the side frame 135 (direction perpendicular to the surface of the exterior member 130), the rear end 167 of the power supply board 144 overlaps with the supply drive frame 164. When viewed from the direction from the exterior member 130 toward the side frame 135 (direction perpendicular to the surface of the exterior member 130), the front end 168 of the power supply board 144 overlaps with the louver 131. As a result, by arranging the power supply board 144 at an angle so that the distance L3 between the rear end 167 and the side frame 135 is larger than the distance L4 between the front end 168 and the side frame 135 (L3>L4), it is possible to effectively utilize space and reduce the size of the device. [Explanation of symbols]

[0034] 100 Image forming device 101 Image forming section 102 Recording medium supply unit 103 Fixing unit 105 Cartridge 130 Exterior materials 131 Louver 132 Handle 133 Inlet opening 134 Inlet 135 Side Frame 136 Drive Unit 137 Air Duct 138 Power Supply Unit 139 Image formation drive frame 141 Image forming drive unit 140 Motor 142 Fans 144 Power supply board (electronic circuit board) 145 Substrate holding member 146 Inlet retaining member 147 Board holding surface 148 bis 149 Electronic Circuit Elements 150 Connector 151 First mounting surface 152 Second mounting surface 153 Power supply mounting material 160 Bottom 162 Supply drive unit 163 Supply Motor 164 Supply Drive Frame 169 Circuit board mounting parts 170 Exterior front side P Recording medium

Claims

1. an image forming unit that forms an image on a recording medium; a first frame and a second frame disposed to sandwich the image forming unit and supporting the image forming unit; an exterior member covering the first frame and extending along a surface of the first frame; an electronic circuit board provided on a side opposite to the image forming unit with respect to a surface of the first frame and disposed between the first frame and the exterior member; A drive unit having a motor, a mounting surface of the electronic circuit board extends in a direction intersecting with a surface of the exterior member, the mounting surface extends in a direction intersecting a surface of the first frame, the drive unit is provided on a side opposite to the image forming unit with respect to a surface of the first frame, and is disposed between the first frame and the exterior member; an image forming apparatus characterized in that, when viewed from a direction perpendicular to the surface of the exterior member, the drive unit and a first end of the electronic circuit board overlap, and the electronic circuit board is tilted so that the first end is away from the drive unit.

2. The exterior member has a recess formed therein, 2. The image forming apparatus according to claim 1, wherein, when viewed from a direction perpendicular to the surface of the exterior member, the recess and the second end of the electronic circuit board overlap, and the electronic circuit board is tilted so that the second end is away from the recess.

3. 3. The image forming apparatus according to claim 2, wherein the height of the electronic circuit element mounted on the electronic circuit board from the surface of the board increases from the first end toward the second end.

4. 4. The image forming apparatus according to claim 2, wherein the drive unit and the recess are arranged side by side in a vertical direction.

5. 4. The image forming apparatus according to claim 2, wherein the drive unit and the recess are arranged parallel to a horizontal plane and aligned along a front-rear direction parallel to a surface of the first frame.

6. 6. The image forming apparatus according to claim 2, wherein the recess is a handle or a louver for taking in air from the outside.

7. a board holding member for holding the electronic circuit board; the board holding member includes a holding surface that holds the electronic circuit board, and an attachment surface that intersects with the holding surface and extends along a surface of the first frame, 7. The image forming apparatus according to claim 1, wherein the substrate holding member is attached to the first frame via the attachment surface.

8. an inlet holding member for holding the inlet; 8. The image forming apparatus according to claim 7, wherein the substrate holding member and the first frame are connected via the inlet holding member.

9. 9. The image forming apparatus according to claim 1, wherein the electronic circuit board is a power supply board that converts AC power supplied from an external source into DC power.

10. the image forming unit includes a rotatable image carrier; 10. An image forming apparatus according to claim 1, wherein the first frame supports a first end of the image carrier in a direction of a rotation axis of the image carrier, and the second frame supports a second end of the image carrier in the direction of the rotation axis.

Images