JP5816579B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus that performs an image forming process on a sheet, and more particularly to an image forming apparatus in which a plurality of substrates including electrical components are disposed.

  In the image forming apparatus, a plurality of substrates including electrical components are disposed in order to operate various apparatuses disposed in the apparatus main body. The plurality of substrates are composed of a high-voltage substrate that transforms commercial AC voltage into a predetermined high-voltage, supplies the high-voltage to the inside of the image forming apparatus, and a control board that outputs various control signals to the image forming apparatus. Is done.

  There is a case where high-frequency electromagnetic noise enters the electrical component arranged on the substrate. For this reason, it is suppressed that the periphery of the said board | substrate is shielded with a shield sheet metal etc., and noise is brought to an electrical component. In the technique described in Patent Document 1, dedicated shields are arranged on a plurality of substrates, respectively, and electrical components mounted on each substrate are electrically protected.

JP 2006-53254 A

  In the technique described in Patent Document 1, the substrate surfaces of a plurality of substrates provided with electrical components are directed in different directions. Further, as described above, a dedicated shield is arranged on each substrate. This increases the volume of space required to surround individual substrates with a shield. Furthermore, the area of the shield made of a metal material increases, leading to an increase in the cost of the apparatus.

  The present invention has been made in view of the above problems, and reduces the space occupied by a plurality of substrates in the apparatus main body as much as possible, and at the same time, the area of the shield component for electrically protecting the electrical component. An object of the present invention is to provide an image forming apparatus with a reduced size.

An image forming apparatus according to an aspect of the present invention is a housing having a substantially rectangular parallelepiped shape, and includes a first surface constituting one side surface of the housing and the housing on a side opposite to the first surface. A housing having a second surface constituting a side surface of the body, a main body frame disposed in the housing and made of a flame-retardant resin material, and the first of the housing An image forming unit that is disposed in an internal space formed between the second surface and the second surface, is supported by the main body frame, and performs an image forming process on the sheet, and the second surface and the image A fourth surface that is vertically disposed between the forming portion and faces the first surface side, and a rear surface of the third surface facing the second surface side. a shield metal plate and a surface, wherein one of the shield metal plate, the lead is directly to disposed in the third plane, the electrical portions which protrude toward the first surface A plurality of substrates, wherein the main body frame includes a wall portion disposed between the shield sheet metal and the image forming unit, and the plurality of substrates include the shield sheet metal and the wall portion. And the housing is formed of a material having a lower flame retardance than the main body frame , and the plurality of substrates have a first height toward the first surface, and the electrical component has the first height. A first region to be disposed; and a second region in which the electrical component is disposed at a second height lower than the first height toward the first surface. The apparatus further includes a component that projects from the wall portion toward the second surface so as to face the region . According to this configuration, the housing includes the first surface and the second surface. An image forming unit is disposed in an internal space formed between the first surface and the second surface. The shield sheet metal is vertically disposed between the image forming unit and the second surface. And a some board | substrate is arrange | positioned vertically on the 3rd surface which faces a 2nd surface side among shield sheet metal. The plurality of substrates include an electrical component protruding toward the first surface. According to this configuration, the plurality of substrates are arranged vertically on the shield sheet metal. For this reason, the space which a plurality of substrates occupies is reduced by arranging a plurality of substrates as much as possible. Further, the region on the second surface side of the electrical component is shielded by the shield sheet metal. For this reason, the electrical components arranged on the plurality of substrates are electrically protected by the shield sheet metal. Therefore, the area of the shield member protecting the substrate is reduced as much as possible as compared with the case where each substrate is accommodated in an individual shield member. Moreover, according to this structure, a some board | substrate is arrange | positioned between a shield sheet metal and the wall part of a main body frame. For this reason, a plurality of substrates provided with electrical components are protected electrically and structurally. Furthermore, according to this configuration, since the main body frame is made of a flame retardant resin material, the plurality of substrates are arranged between the wall portion made of the flame retardant resin material and the shield metal plate. Is done. For this reason, while the several board | substrate provided with an electrical component is electrically protected, the flame-retardant countermeasure of the said board | substrate is implement | achieved. Further, according to this configuration, the components are arranged on the wall portion of the main body frame so as to face the second region where the electric components are arranged with a relatively low height among the plurality of substrates. For this reason, among the plurality of substrates, the space formed in the second region is effectively used, and the space occupied by the image forming apparatus main body is reduced.

An image forming apparatus according to another aspect of the present invention is a housing having a substantially rectangular parallelepiped shape, and includes a first surface constituting one side surface of the housing and the opposite side of the first surface. A housing provided with a second surface constituting a side surface of the housing, a main body frame disposed inside the housing and made of a flame-retardant resin material, and the first of the housing An image forming unit disposed in an internal space formed between the first surface and the second surface, supported by the main body frame, and performing an image forming process on the sheet; the second surface; A fourth surface that is vertically disposed between the image forming unit and faces the first surface, and a rear surface of the third surface facing the second surface. Of the shield sheet metal, and the electricity disposed vertically on the third surface of the shield sheet metal and projecting toward the first surface A plurality of substrates including a product, wherein the main body frame includes a wall portion disposed between the shield sheet metal and the image forming unit, and the plurality of substrates include the shield sheet metal and the wall portion. The casing is formed of a material having a lower flame retardance than the main body frame, and the plurality of substrates have the first height toward the first surface and the electrical component. A first region where the electrical component is disposed, and a second region where the electrical component is disposed at a second height lower than the first height toward the first surface, and the wall The portion has a raised portion that faces the second region and is raised toward the second surface, and a concave portion that is opposite to the raised portion and faces the first surface. It is characterized by that. According to this configuration, the housing includes the first surface and the second surface. An image forming unit is disposed in an internal space formed between the first surface and the second surface. The shield sheet metal is vertically disposed between the image forming unit and the second surface. And a some board | substrate is arrange | positioned vertically on the 3rd surface which faces a 2nd surface side among shield sheet metal. The plurality of substrates include an electrical component protruding toward the first surface. According to this configuration, the plurality of substrates are arranged vertically on the shield sheet metal. For this reason, the space which a plurality of substrates occupies is reduced by arranging a plurality of substrates as much as possible. Further, the region on the second surface side of the electrical component is shielded by the shield sheet metal. For this reason, the electrical components arranged on the plurality of substrates are electrically protected by the shield sheet metal. Therefore, the area of the shield member protecting the substrate is reduced as much as possible as compared with the case where each substrate is accommodated in an individual shield member. Moreover, according to this structure, a some board | substrate is arrange | positioned between a shield sheet metal and the wall part of a main body frame. For this reason, a plurality of substrates provided with electrical components are protected electrically and structurally. Furthermore, according to this configuration, since the main body frame is made of a flame retardant resin material, the plurality of substrates are arranged between the wall portion made of the flame retardant resin material and the shield metal plate. Is done. For this reason, while the several board | substrate provided with an electrical component is electrically protected, the flame-retardant countermeasure of the said board | substrate is implement | achieved. Moreover, according to this structure, the raised part of the wall part of a main body frame is arrange | positioned facing the 2nd area | region where an electrical component is arrange | positioned with a relatively low height among several board | substrates. A concave portion is formed on the opposite side of the raised portion, and a part of the internal space in which the image forming portion is arranged is enlarged to the second surface side. For this reason, it becomes possible to arrange | position so that another component may approach into this recessed part. As a result, the space formed in the second region among the plurality of substrates is effectively used.

  Said structure WHEREIN: It is preferable that these board | substrates are electrically connected with respect to the said shield metal plate.

  According to this configuration, since the shield sheet metal is grounded and the plurality of substrates are electrically connected to the shield sheet metal, the grounding of the plurality of substrates is realized. For this reason, poor grounding of a plurality of substrates is suppressed.

  In the above configuration, it is preferable that the shield sheet metal has a rectangular shape, further includes a plurality of electrical connectors disposed on the substrate and disposed along one side of the rectangular shape of the shield sheet metal. .

  According to this configuration, the plurality of electrical connectors are arranged along one side of the shield sheet metal. For this reason, the electric wires electrically connected to the plurality of substrates can be intensively arranged.

  According to the present invention, there is provided an image forming apparatus in which the space occupied by a plurality of substrates in the apparatus main body is reduced as much as possible and the area of the shield part for electrically protecting the electric part is reduced. . In particular, since the plurality of substrates are arranged along one surface of the housing, the apparatus can be miniaturized. Further, since the shield sheet metal is disposed outside the plurality of substrates, the plurality of substrates are electrically protected.

1 is a perspective view illustrating an appearance of an image forming apparatus 1 according to an embodiment of the present disclosure. 1 is a perspective view showing an internal structure of an image forming apparatus 1 according to an embodiment of the present invention. 1 is a side sectional view showing an internal structure of an image forming apparatus 1 according to an embodiment of the present invention. 1 is a perspective view for explaining an internal structure of an image forming apparatus 1 according to an embodiment of the present disclosure. It is a perspective view showing the appearance of substrate unit 70 concerning one embodiment of the present invention. It is a perspective view for explaining main body frame 10A concerning one embodiment of the present invention. It is a perspective view for explaining main body frame 10A concerning one embodiment of the present invention. It is a perspective view for explaining main body frame 10A concerning one embodiment of the present invention. It is a section perspective view for explaining main part frame 10A concerning one embodiment of the present invention. It is sectional drawing for demonstrating 10 A of main body frames which concern on one Embodiment of this invention. It is sectional drawing for demonstrating 10 A of main body frames which concern on other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In order to describe the image forming apparatus 1 according to the present embodiment, front, back, up, down, and left and right arrows are shown in each drawing, but the orientation of the image forming apparatus 1 is not limited to these. FIG. 1 is a perspective view showing an appearance of an image forming apparatus 1 according to an embodiment of the present invention. FIG. 2 is a perspective view showing the internal structure of the image forming apparatus 1. FIG. 2 shows a state in which each cover and image forming unit 30 described later are removed from FIG. FIG. 3 is a side sectional view showing the internal structure of the image forming apparatus 1. FIG. 4 is a perspective view showing the arrangement of the board unit 70, and FIG. 5 is a perspective view showing the configuration of the board unit 70. Here, a monochrome printer is illustrated as the image forming apparatus 1, but the image forming apparatus may be a copying machine, a facsimile machine, or a multifunction machine having these functions, and an image forming apparatus that forms a color image. It may be.

  The image forming apparatus 1 includes a main body housing 10 (housing) having a substantially rectangular parallelepiped housing structure, a paper feeding unit 20, an image forming unit 30, a fixing unit 40, and a toner container 50 housed in the main body housing 10. A substrate unit 70 and a cooling fan 80.

  A front cover 11 is provided on the front side of the main body housing 10, and a rear cover 12 is provided on the rear side. By opening the front cover 11, the toner container 50 is exposed as shown in FIG. Thereby, the user can take out the toner container 50 from the front side of the main body housing 10 when the toner runs out. The rear cover 12 is a cover that is opened at the time of sheet jam or maintenance. The units of the image forming unit 30 and the fixing unit 40 can be taken out from the rear side of the main body housing 10 by opening the rear cover 12. Further, on the side surface of the main body housing 10, a left cover 12L (FIG. 1) (first surface) and a right cover 12R on the opposite side of the left cover 12L (not shown in FIG. 1) (second surface) Are arranged so as to extend in the vertical direction. An intake port 12La for taking in air into the main body housing 10 is disposed in the front portion of the left cover 12L. Further, on the upper surface of the main body housing 10, a paper discharge unit 13 for discharging the sheet after image formation is provided. Various devices for executing image formation are installed in an internal space S (FIG. 2) defined by the front cover 11, the rear cover 12, the left cover 12L, the right cover 12R, and the paper discharge unit 13. The

  Inside the main body housing 10, a main body frame 10A that is exposed by removing the front cover 11, the rear cover 12, the left cover 12L, and the right cover 12R is disposed. The main body frame 10A is a skeleton part of the image forming apparatus 1 having a box shape. The main body frame 10A is made of a flame retardant resin material. In the present embodiment, a resin material suitable for the flame retardancy grade (V0) is adopted for the main body frame 10A based on the UL standard. The fire prevention enclosure of the image forming apparatus 1 is satisfied by the main body frame 10A. That is, it is possible to employ a material having a flame retardance grade lower than that of the main body frame 10A for the front cover 11, the rear cover 12, the left cover 12L, and the right cover 12R disposed outside the main body frame 10A. Become. As a result, it is possible to reduce the cost of the resin material employed in the image forming apparatus 1 while maintaining the fire prevention performance required for the image forming apparatus 1.

  The main body frame 10A includes a left frame 10L and a right frame 10R (FIG. 2). The left frame 10L supports various devices on the left cover 12L side of the main body frame 10A. The right frame 10R supports various devices on the right cover 12R side of the main body frame 10A. The left frame 10L and the right frame 10R support the image forming unit 30 and the fixing unit 40 that extend in the left-right direction.

  The paper feeding unit 20 includes a paper feeding cassette 21 that stores sheets to be subjected to image forming processing (FIG. 3). A part of the sheet feeding cassette 21 protrudes further forward from the front surface of the main body housing 10. An upper surface of a portion of the sheet cassette 21 accommodated in the main body housing 10 is covered with a sheet cassette top plate 21U. The sheet feeding cassette 21 is provided with a sheet accommodating space for accommodating the bundle of sheets, a lift plate for lifting the bundle of sheets for feeding. A sheet feeding portion 21 </ b> A is provided at an upper portion on the rear end side of the sheet feeding cassette 21. The sheet feeding unit 21A is provided with a sheet feeding roller 21B for feeding the uppermost sheet of the sheet bundle in the sheet feeding cassette 21 one by one.

  The image forming unit 30 performs an image forming process for forming a toner image on a sheet fed from the paper feeding unit 20. The image forming unit 30 includes a photosensitive drum 31, a charging device 32, an exposure device (not shown in FIG. 3), a developing device 33, a transfer roller 34, and a cleaning device disposed around the photosensitive drum 31. 35. The image forming unit 30 is disposed between the left cover 12L (first surface) and the right cover 12R (second surface), more specifically, between the left frame 10L and the right frame 10R.

  The photosensitive drum 31 rotates around its axis, and an electrostatic latent image and a toner image are formed on its peripheral surface. As the photosensitive drum 31, a photosensitive drum using an amorphous silicon (a-Si) material can be used. The charging device 32 uniformly charges the surface of the photosensitive drum 31, and includes a charging roller that contacts the photosensitive drum 31. The cleaning device 35 has a cleaning roller and the like, cleans the toner attached to the peripheral surface of the photosensitive drum 31 after the toner image is transferred, and conveys the toner to a collecting device (not shown). The photosensitive drum 31, the charging device 32, and the cleaning device 35 are integrally configured as a drum unit (not shown).

  The exposure apparatus has a laser light source and optical equipment such as a mirror and a lens, and irradiates the peripheral surface of the photosensitive drum 31 with light modulated based on image data given from an external device such as a personal computer. An electrostatic latent image is formed. The developing device 33 supplies toner to the peripheral surface of the photosensitive drum 31 in order to develop the electrostatic latent image on the photosensitive drum 31 to form a toner image. The developing device 33 includes a developing roller 331 that carries toner to be supplied to the photosensitive drum 31, a first conveying screw 332 and a second conveying screw 333 that circulate and convey the developer inside a developing housing (not shown). including.

  The transfer roller 34 is a roller for transferring a toner image formed on the peripheral surface of the photosensitive drum 31 onto a sheet, and forms a transfer nip portion with the photosensitive drum 31. The transfer roller 34 is given a transfer bias having a polarity opposite to that of the toner.

  The fixing unit 40 performs a fixing process for fixing the transferred toner image on the sheet. The fixing unit 40 includes a fixing roller 41 having a heating source therein, and a pressure roller 42 that is pressed against the fixing roller 41 and forms a fixing nip portion with the fixing roller 41. When the sheet on which the toner image has been transferred is passed through the fixing nip portion, the toner image is fixed on the sheet by heating by the fixing roller 41 and pressing by the pressure roller 42.

  The toner container 50 stores toner to be supplied to the developing device 33. The toner container 50 includes a container main body 51 serving as a main storage location of toner, a cylindrical portion 52 projecting from a lower portion on one side surface of the container main body 51, and a lid member 53 covering the other side surface of the container main body 51. And a rotating member 54 that is contained in the container and conveys toner. The toner stored in the toner container 50 is supplied into the developing device 33 from the toner discharge port 521 provided on the lower surface of the front end of the cylindrical portion 52 when the rotating member 54 is driven to rotate. The toner container 50 is disposed at a position immediately above (right inside) the left frame 10L (FIG. 2). Further, the container 50 is located below the paper discharge unit 13 (see FIG. 3).

  In the main body housing 10, a main conveyance path 22F and a reverse conveyance path 22B are provided to convey the sheet. The main conveyance path 22 </ b> F passes through the image feeding unit 21 and the fixing unit 40 from the sheet feeding unit 21 </ b> A of the paper feeding unit 20, and the paper discharge port 14 provided to face the paper discharge unit 13 on the upper surface of the main body housing 10. It extends to. The reverse conveyance path 22B is a conveyance path for returning a sheet printed on one side to the upstream side of the image forming unit 30 in the main conveyance path 22F when performing duplex printing on the sheet.

  A registration roller pair 23 is arranged on the upstream side of the transfer nip portion between the photosensitive drum 31 and the transfer roller 34 in the main conveyance path 22F. After the sheet is temporarily stopped by the registration roller pair 23 and skew correction is performed, the sheet is sent out to the transfer nip portion at a predetermined timing for image transfer. A plurality of transport rollers for transporting the sheet are disposed at appropriate positions on the main transport path 22F and the reverse transport path 22B. For example, a pair of paper discharge rollers 24 is disposed in the vicinity of the paper discharge port 14.

  The reverse conveyance path 22 </ b> B is formed between the outer side surface of the reverse unit 25 and the inner surface of the rear cover 12 of the main body housing 10. Note that one roller of the transfer roller 34 and the registration roller pair 23 is mounted on the inner surface of the reversing unit 25. The rear cover 12 and the reversing unit 25 can be rotated about the axis of the fulcrum 121 provided at the lower end thereof. When a sheet jam occurs in the reverse conveyance path 22B, the rear cover 12 is opened. When a sheet jam occurs in the main conveyance path 22F, or when the unit of the photosensitive drum 31 and the developing device 33 are taken out, the reversing unit 25 is opened in addition to the rear cover 12.

  The cooling fan 80 (FIG. 2) is disposed on the outside (left side) of the left frame 10L and on the front side of the left frame 10L. That is, the cooling fan 80 is disposed between the left cover 12L and the image forming unit 30 in the left-right direction (the direction intersecting the left cover 12L and the right cover 12R) (see FIG. 2). The cooling fan 80 includes a rotating shaft (not shown), a fan motor (not shown), and a plurality of blade members 80H (FIG. 4). The fan motor rotates when a driving current is supplied from a power source (not shown), and rotates the blade member 80H via the rotating shaft. The blade member 80H rotates while forming a rotation surface substantially parallel to the left cover 12L. By rotation of the blade member 80H, air outside the main body housing 10 is sucked from the air inlet 12La, and an air flow toward the inside of the main body housing 10 is brought about.

  The board unit 70 is disposed on the outer side (right side) of the right frame 10R (FIG. 2). That is, the substrate unit 70 is disposed between the right cover 12R and the image forming unit 30 in the left-right direction (the direction intersecting the left cover 12L and the right cover 12R) (see FIG. 4). In the board unit 70, a plurality of circuit boards are gathered and arranged.

  Referring to FIG. 5, the board unit 70 includes a shield metal plate 71, a power supply board 72 (board), a high voltage board 73 (board), and a control board 74 (board).

  The shield sheet metal 71 is a sheet metal that defines one side surface of the substrate unit 70 and holds the plurality of substrates. The shield metal plate 71 has a substantially rectangular shape. The shield metal plate 71 is disposed between the right cover 12R and the right frame 10R in parallel with the right cover 12R and the right frame 10R and vertically (see FIGS. 2 and 4). The shield sheet metal 71 includes a sheet metal inner surface portion 701 (third surface) and a sheet metal outer surface portion 702 (fourth surface) (FIG. 8). The sheet metal inner surface portion 701 is a surface of the shield sheet metal 71 facing the left cover 12L (FIG. 1), and the sheet metal outer surface portion 702 is a surface facing the right cover 12R side. The shield metal plate 71 is disposed inside the image forming apparatus 1 and has a function of electrically protecting the plurality of substrates.

  The power supply substrate 72 includes a flat wiring board 72a, a plurality of electric elements 72b (electric parts) mounted on the wiring board 72a, a coil 72c (electric parts), and a first capacitor 72d (electric parts). And a second capacitor 72e (electrical component). The power supply substrate 72 is a main power supply for the image forming apparatus 1. The power supply substrate 72 is a substrate for generating voltages of 24V and 5V. The power supply voltage is supplied to an electric device housed in the image forming apparatus 1. The electric element 72b, the coil 72c, the first capacitor 72d, and the second capacitor 72e are fixed to the wiring board 72a so as to project from the wiring board 72a toward the left (toward the left cover 12L). . The power supply substrate 72 is vertically disposed on the sheet metal inner surface portion 701 of the shield sheet metal 71 together with other substrates.

  The high voltage substrate 73 includes a flat upper substrate 73a and a high voltage power supply box 73b mounted on the upper substrate 73a. The high voltage substrate 73 transforms the commercial AC voltage to a predetermined high voltage and supplies the predetermined voltage to the internal equipment of the image forming apparatus 1. The high voltage power supply box 73b includes a power supply unit 73c (electrical part). The power supply unit 73c has a substantially L shape. The power supply unit 73c includes an electrical component inside and is disposed on the upper substrate 73a so as to project leftward. The high voltage substrate 73 is vertically disposed on the sheet metal inner surface portion 701 of the shield sheet metal 71 together with other substrates.

  The control board 74 includes a flat support board 74a and a control box 74b (electrical component) mounted on the support board 74a. Various electric elements are arranged in the control box 74b. The control board 74 outputs various control signals to the image forming apparatus 1. The control box 74b is disposed on the support substrate 74a so as to project leftward. The control board 74 is vertically disposed on the sheet metal inner surface portion 701 of the shield sheet metal 71 together with other boards.

  As shown in FIG. 4, in the present embodiment, the wiring board 72a, the upper board 73a, and the support board 74a are arranged adjacent to each other on a wide surface of the shield metal plate 71. In addition, the control board 74 and the high-voltage board 73 are arranged in a substantially vertical direction (upward) with respect to the power supply board 72 in a direction along each other. Thus, in the present embodiment, a plurality of substrates are arranged as much as possible on the substrate unit 70 arranged between the right cover 12R and the right frame 10R. For this reason, the occupied space of the main body housing 10 is reduced as compared with the case where a plurality of substrates are dispersedly arranged in the main body housing 10.

  In particular, in the present embodiment, the image forming unit 30 is disposed in the internal space S (FIG. 2), and the substrate unit 70 is disposed between the image forming unit 30 and the right cover 12R. For this reason, it is possible to dispose a plurality of substrates using the height of the image forming unit 30, and the occupied space in the height direction of the image forming apparatus 1 is reduced as much as possible.

  Further, the board unit 70 includes a connector portion 95. The connector unit 95 includes a first connector 95a, a second connector 95b, and a third connector 95c. Each of these connectors supplies a predetermined voltage to the electrical components on each board held by the shield metal plate 71. Each of these connectors supplies a predetermined voltage generated from the electrical components on each of the substrates to each device in the image forming apparatus 1. The first connector 95a, the second connector 95b, and the third connector 95c are disposed along the rear side (one side) of the shield metal plate 71. For this reason, the connectors connected to the board unit 70 in the main body housing 10 are gathered in one place. As a result, in the main body housing 10, the arrangement of electric wires that are electrically connected to the plurality of substrates is integrated as much as possible.

  In the present embodiment, the power supply substrate 72, the high-voltage substrate 73, and the control substrate 74 are electrically connected to the shield metal plate 71. A predetermined ground wire that is grounded in advance is connected to the shield metal plate 71. As a result, the grounding of the power supply board 72, the high voltage board 73, and the control board 74 is realized by the ground wire. For this reason, poor grounding of each substrate is suppressed, and the image forming apparatus 1 can operate stably and electrically.

  Next, the arrangement of the main body frame 10A and the board unit 70 will be described in more detail with reference to FIGS. 6 is a perspective view of a single body frame 10A, and FIG. 7 is a perspective view showing a state in which a plurality of electrical components are attached to the body frame 10A of FIG. Further, FIG. 8 is a perspective view showing a state in which the substrate unit 70 is attached to the main body frame 10A of FIG.

  Referring to FIG. 6, main body frame 10A includes a bottom frame 10S, a left frame 10L, a right frame 10R, a rear frame 10B, a container top plate 50H, and a front frame 10F. Furthermore, the main body frame 10A includes a bottom protrusion 10S1, a front protrusion 10S2, a top protrusion 10S3, and a rear protrusion 10S4.

  The bottom frame 10S corresponds to the bottom portion of the main body frame 10A. The left frame 10L and the right frame 10R described above are arranged at the left and right ends of the bottom frame 10S so as to be erected upward.

  The rear frame 10B is disposed in the rear portion of the left frame 10L and the right frame 10R. In the rear frame 10B, the left frame 10L and the right frame 10R are connected in series on the rear side of the main body frame 10A.

  The container top plate 50H and the front frame 10F are disposed in front portions of the left frame 10L and the right frame 10R. The container top plate 50H and the front frame 10F are disposed adjacent to each other in the left-right direction. The container top plate 50H and the front frame 10F connect the front portions of the left frame 10L and the right frame 10R.

  The bottom protrusion 10S1 is disposed in the lower portion of the right frame 10R. The bottom protrusion 10S1 is arranged such that the right end of the bottom frame 10S extends to the right (outside) than the right frame 10R. The front protrusion 10S2, the upper protrusion 10S3, and the rear protrusion 10S4 are wall portions connected to the right frame 10R. The front protrusion 10S2, the upper protrusion 10S3, and the rear protrusion 10S4 are each formed such that a part of the front side edge, the upper side edge, and the rear side edge of the right frame 10R protrude rightward. .

  Referring to FIG. 7, when assembling image forming apparatus 1, various components are mounted on main body frame 10A of FIG. An inner cover 11A is disposed below the front frame 10F of the main body frame 10A. A first unit 905, a second unit 906, and a third unit 907 are arranged on the right side surface of the right frame 10R. The first units 905 and 906 and the third unit 907 are electrical components that supply a predetermined drive voltage or control voltage to the image forming apparatus 1. The first unit 905, the second unit 906, and the third unit 907 are mounted on the right frame 10 </ b> R with a bottom protrusion 10 </ b> S <b> 1 having a height that is lower than the height protruding from the right frame 10 </ b> R toward the right side.

  Referring to FIG. 8, substrate unit 70 is mounted on main body frame 10A so as to face right frame 10R of main body frame 10A of FIG. At this time, the power supply board 72, the high voltage board 73, and the control board 74 (FIG. 5) of the board unit 70 are arranged so as to face the right frame 10R. The power supply board 72, the high-voltage board 73, and the control board 74 of the board unit 70 are spaces defined by the right frame 10R of the main body frame 10A, the bottom projection 10S1, the front projection 10S2, the top projection 10S3, and the rear projection 10S4. It is arranged to enter. And the connector part 95 is arrange | positioned around the back side edge | side of the board | substrate unit 70 with which the main body frame 10A was mounted | worn.

  With reference to FIG. 9 and FIG. 10, the arrangement of the substrate unit 70 will be described in more detail. FIG. 9 is a cross-sectional perspective view in which the main body frame 10A of FIG. 8 is cut out on a plane passing through points A, B, C, and D. FIG. 10 is a front sectional view of FIG. 9 viewed from the front side. In any case, the substrate unit 70 corresponds to a cut view in the front-rear direction.

  The board unit 70 mounted on the main body frame 10A is disposed at the right end of the main body frame 10A. Of the shield sheet metal 71 of the substrate unit 70, a power supply board 72, a high-voltage board 73, and a control board 74 are disposed on the sheet metal inner surface 701 side (FIG. 5). The electric parts represented by the power source 73c of the high-voltage board 73, the coil 72c of the power board 72, and the first capacitor 72d are projected from the sheet metal inner surface 701 toward the left.

  Thus, the power supply board 72, the high voltage board 73, and the control board 74 of the board unit 70 are arranged in a space surrounded by the shield metal plate 71 on the right side and the right frame 10R on the left side. Then, the outer side (right side) of the electrical component mounted on each substrate is shielded by the shield metal plate 71, so that the electrical component is electrically protected. Accordingly, it is possible to prevent the electrical components of the power supply board 72, the high-voltage board 73, and the control board 74 from malfunctioning due to noise transmitted from the outside of the image forming apparatus 1. In particular, in this embodiment, the power supply board 72, the high voltage board 73, and the control board 74 are mounted on the single shield metal plate 71, so that the power supply board 72, the high voltage board 73, and the control board 74 are electrically connected. Protected. Therefore, the area of the shield member that electrically protects the substrate unit 70 is reduced and the cost of the substrate unit 70 is reduced as compared with the case where each substrate is accommodated in an individual shield member.

  Furthermore, the right frame 10 </ b> R is disposed to face the inside (left side) of each electrical component. The right frame 10R is made of a flame retardant resin material. The electric component of the board unit 70 is surrounded by the shield metal plate 71 made of a metal plate and the right frame 10R, thereby realizing a flame retardant measure (fireproof enclosure) for the electric component. In the present embodiment, the main body frame 10A is a frame portion that supports the main body housing 10, and the image forming unit 30 is accommodated in an internal space S (FIG. 2) formed by the main body frame 10A. Therefore, the main body frame 10 </ b> A realizes not only flame retardant measures for the substrate unit 70 but also flame retardant measures for the image forming unit 30.

  Referring to FIG. 10, in the sheet metal inner surface portion 701 of the substrate unit 70, a region Y in which a tall electrical component is mounted like the coil 72c (first region), and a power source unit 73c, A region Z (second region) where electrical components shorter than the region Y are mounted is mixed. In the present embodiment, parts such as the third unit 907 are arranged on the right frame 10R so as to face the region Z. That is, among the electrical components arranged on the sheet metal inner surface portion 701 of the substrate unit 70, a vacant space such as the region Z is formed on the left side of the short electrical component. And this space is utilized suitably and the space in the main body housing 10 is effectively utilized by arrange | positioning components in the right frame 10R. As a result, the space occupied by the image forming apparatus 1 is reduced as much as possible.

  The image forming apparatus 1 according to the embodiment of the present invention has been described above. However, the present invention is not limited thereto, and for example, the following modified embodiment can be taken.

  In the above-described embodiment, the description has been made in the aspect in which the parts such as the third unit 907 are arranged on the right frame 10R facing the region Z of the sheet metal inner surface portion 701, but the present invention is limited to this. is not. FIG. 11 is a cross-sectional view showing another mode in which the above-described region Z is preferably used. The right frame 10 </ b> R faces the region Z of the sheet metal inner surface portion 701 and is raised toward the sheet metal inner surface portion 701, and is opposite to the raised portion 110 and faces the left cover 12 </ b> L. And a recess 111. In this case, the raised portion 110 of the right frame 10 </ b> R is raised on the right side so as to fill the left space (vacant space) of the electrical component in the region Z of the sheet metal inner surface portion 701. Then, when the raised portion 110 is raised to the right side, a concave portion 111 is formed on the opposite side (left side, back side) of the raised portion 110. Therefore, the internal space S on the left side of the right frame 10R is partially enlarged (Sp in FIG. 11), and the degree of freedom in arrangement of the image forming unit 30 and the like is increased.

10 Main body housing (housing)
10A body frame 10R right frame (wall)
10L Left frame 10F Front frame 10S Bottom frame 10S1 Bottom projection 10S2 Front projection 10S3 Top projection 10S4 Rear projection 10B Rear frame 11 Front cover 11A Inner cover 11B Inclined cover 12 Rear cover 12L Left cover (first surface)
12R Right cover (second surface)
12La Intake port 13 Paper discharge unit 14 Paper discharge port 20 Paper feed unit 21 Paper feed cassette 21U Paper feed cassette top plate 22F Main transport path 24 Paper discharge roller pair 30 Image forming unit 31 Photosensitive drum 32 Charging device 33 Development device 331 Development Roller 34 Transfer roller 35 Cleaning device 35H Cleaner housing 40 Fixing unit 41 Fixing roller 42 Pressure roller 50 Toner container 50H Container top plate 70 Substrate unit 71 Shield metal plate 701 Sheet metal inner surface (third surface)
702 Sheet metal outer surface (fourth surface)
72 Power supply board (board)
72a Wiring board 72b Electric element 72c Coil 72d First capacitor 72e Second capacitor 73 High voltage substrate (substrate)
73a Upper board 73b High voltage power supply box 73c Power supply part 74 Control board (board)
74a Support substrate 74b Control box 80 Cooling fan 905 First unit 906 Second unit 907 Third unit (component)
95 Connector portion 95a First connector (electrical connector)
95b Second connector (electrical connector)
95c Third connector (electrical connector)

Claims (4)

A housing having a substantially rectangular parallelepiped shape, a first surface constituting one side surface of the housing, and a second surface constituting a side surface of the housing opposite to the first surface; A housing with
A main body frame disposed inside the housing and made of a flame-retardant resin material;
An image forming unit disposed in an internal space formed between the first surface and the second surface of the housing, supported by the main body frame, and performing an image forming process on the sheet;
A third surface vertically disposed between the second surface and the image forming unit and facing the first surface; and the third surface facing the second surface . A shield sheet metal comprising a fourth surface which is the back surface of the surface ;
Wherein among the shield metal plate, wherein the third lead straight to arranged on the surface of, anda plurality of substrates comprise an electrical component that is protruded toward the first surface,
The main body frame includes a wall portion disposed between the shield sheet metal and the image forming portion,
The plurality of substrates are disposed between the shield sheet metal and the wall portion,
The housing is formed of a material that is less flame retardant than the body frame ,
The plurality of substrates include a first region in which the electrical component is arranged with a first height toward the first surface, and a first region that is lower than the first height toward the first surface. A second region in which the electrical component is disposed with a height of 2;
An image forming apparatus , further comprising a component that projects from the wall portion toward the second surface so as to face the second region. A housing having a substantially rectangular parallelepiped shape, a first surface constituting one side surface of the housing, and a second surface constituting a side surface of the housing opposite to the first surface; A housing with
A main body frame disposed inside the housing and made of a flame-retardant resin material;
An image forming unit disposed in an internal space formed between the first surface and the second surface of the housing, supported by the main body frame, and performing an image forming process on the sheet;
A third surface vertically disposed between the second surface and the image forming unit and facing the first surface; and the third surface facing the second surface . A shield sheet metal comprising a fourth surface which is the back surface of the surface ;
Among the shield metal plates, a plurality of substrates that are vertically disposed on the third surface and include electrical components that protrude toward the first surface;
The main body frame includes a wall portion disposed between the shield sheet metal and the image forming portion,
The plurality of substrates are disposed between the shield sheet metal and the wall portion,
The housing is formed of a material that is less flame retardant than the body frame ,
The plurality of substrates include a first region in which the electrical component is arranged with a first height toward the first surface, and a first region that is lower than the first height toward the first surface. A second region in which the electrical component is disposed with a height of 2;
The wall is
A raised portion facing the second region and raised toward the second surface;
An image forming apparatus comprising: a recess opposite to the raised portion and facing the first surface . The shield sheet metal is grounded,
Wherein the plurality of substrates, the shield metal plate, an image forming apparatus according to claim 1 or 2, characterized in that it is electrically connected. The shield sheet metal has a rectangular shape,
Disposed on said substrate and along one side of the rectangular shape of the shield metal plate, a plurality of electrical connectors disposed, according to any one of claims 1 to 3, characterized by further comprising Image forming apparatus.