Patent Description:
In recent years it is common for such an image forming apparatus as a laser printer to include a wireless communication portion, so that the user can instruct various operations, such as printing and settings, to the image forming apparatus using an external device via wireless communication, in order to improve user friendliness. In the wireless communication portion, a wireless communication board (wireless module) that includes an antenna is disposed independently from a control board. The control board and the wireless communication board are connected, and an instruction from an external device is transferred from the wireless communication board to the control board. In this transfer, the communication performance of the wireless communication is influenced by the position of the wireless communication board inside the image forming apparatus and the presence of peripheral members of the wireless communication board.

As a configuration to ensure good wireless communication performance, <CIT> discloses an apparatus in which the control board and the wireless communication board are directly connected and a recessed portion is formed on a side plate, so that the antenna does not overlap with the surface of the side plate of the frame. Document <CIT> discloses an image forming device. Document <CIT> discloses an image forming apparatus. Document <CIT> discloses an image forming device. Document <CIT> discloses an image forming apparatus. Document <CIT> discloses an image forming apparatus. Documents <CIT> and <CIT> disclose also an image forming apparatus.

However, in the case of the apparatus disclosed in <CIT>, the metal frame is located on the apparatus front side with respect to the wireless communication board, hence the wireless communication performance in the apparatus front direction may drop. If the operation portion and the discharged paper stacking portion are disposed on the apparatus front side and the user uses the apparatus from the apparatus front side, wireless communication using an external device is often performed from the front side of the apparatus, and in this case, a drop in wireless communication performance on the apparatus front side is particularly undesirable. On the other hand, if the wireless communication board is disposed on the apparatus front side in order to improve the wireless communication performance on the apparatus front side, then the distance between the control board, which is disposed on the apparatus rear side, and the wireless communication board increases. Therefore the cable communication portion increases and the apparatus becomes vulnerable to noise, which in some cases deteriorates wireless communication performance. Further, forming a notch, such as a recessed portion, on the frame leads to a decrease in rigidity of the apparatus.

With the foregoing in view, the present invention provides an image forming apparatus configured to perform wireless communication that can ensure rigidity of the apparatus and also ensure good communication performance.

The present invention in its one aspect provides an image forming apparatus as specified in claims <NUM> to <NUM>.

According to the present invention, an image forming apparatus configured to perform wireless communication that can ensure rigidity of the apparatus and also ensure good communication performance can be provided.

Hereinafter, a description will be given, with reference to the drawings, of embodiments (examples) of the present invention. However, the sizes, materials, shapes, their relative arrangements, or the like of constituents described in the embodiments may be appropriately changed according to the configurations, various conditions, or the like of apparatuses to which the invention is applied. Therefore, the sizes, materials, shapes, their relative arrangements, or the like of the constituents described in the embodiments do not intend to limit the scope of the invention to the following embodiments.

In Embodiment <NUM>, a case where the present invention is applied to a tandem (four-drum type) color laser beam printer, which can form full color images using an electrophotographic system, will be described. Application of the present invention is not limited to this, and the present invention is also applicable to copiers, printers and the like using an electrostatic recording system or an inkjet recording system.

In the following description, directions are defined with respect to the user who is using the image forming apparatus <NUM>. In other words, in a state of using the image forming apparatus <NUM>, front side (front face side) of the image forming apparatus <NUM> that the user is facing is "front", rear face side (back side) is "rear"; upper face side (top face side) is "up", and lower face side (bottom face side) is "down". The left side face side of the image forming apparatus <NUM>, when the image forming apparatus <NUM> is viewed from the front face side, is "left", and the right side face side thereof is "right".

<FIG> is a schematic cross-sectional view from the left side face side depicting a general configuration of the image forming apparatus <NUM> using an electrophotographic recording technique according to Embodiment <NUM> of the present invention. The image forming apparatus <NUM> includes an image forming portion and a fixing portion supported by a metal frame <NUM>. The image forming apparatus <NUM> includes four image forming portions which are disposed approximately on a line, and each of the image forming portions forms an image of a color respectively: yellow (hereafter Y), magenta (hereafter M), cyan (hereafter C) or black (hereafter K). In the present embodiment, the configuration and operation of each image forming portion are substantially the same, except that a color of an image to be formed is different. Hence unless special differentiation is required, the suffix Y, M, C or K, which is attached to a reference sign to indicate the color handled by the composing element, is omitted in the following description.

Each image forming portion includes a photosensitive drum <NUM> (image bearing member), a charging roller <NUM>, a developing roller <NUM>, and a toner container <NUM>. The image forming portion may have a configuration of a process cartridge, which is integrally detachable from the apparatus. When image information is received and the image forming operation is started, the photosensitive drum <NUM> is rotated in the arrow direction indicated in <FIG>. First the outer peripheral surface of the photosensitive drum <NUM> is uniformly charged by the charging roller <NUM>, and the charged surface is irradiated with a laser beam <NUM> from a scanner unit <NUM> in accordance with the image information, so as to form an electrostatic latent image. The latent image becomes visible by the developing roller <NUM>, whereby a toner image is formed on the surface of the photosensitive drum. The toner image formed by each image forming portion is transferred to an intermediate transfer belt <NUM> (intermediate transfer member).

The intermediate transfer belt <NUM>, which is an endless belt member, is stretched by a driver roller <NUM> and a driven roller <NUM>, along the direction where the image forming portions are disposed. The intermediate transfer belt <NUM> rotates along each image forming portion by the driver roller <NUM> rotating in accordance with a print instruction. On an inner peripheral surface side of the intermediate transfer belt <NUM>, a primary roller <NUM> is disposed so as to face the photosensitive drum <NUM>, and a toner image formed by each image forming portion is sequentially transferred to the intermediate transfer belt <NUM> by the primary roller <NUM> pressing the intermediate transfer belt <NUM> toward the photosensitive drum <NUM>. The toner image transferred to the intermediate transfer belt <NUM> is conveyed to a transfer nip portion (contact portion with a secondary transfer roller <NUM>) by the intermediate transfer belt <NUM> further rotating.

A sheet type recording material P, which is stored in a feeding cassette <NUM> disposed in a lower portion of the image forming apparatus <NUM> before forming an image, is separated and fed one-by-one from the feeding cassette <NUM> to a resist roller pair <NUM> by a feeding roller <NUM>. The resist roller pair <NUM> conveys the recording material P which was fed into a transfer nip portion between the intermediate transfer belt <NUM> and a secondary transfer roller <NUM>. The secondary transfer roller <NUM> is disposed to face the driver roller <NUM> with the intermediate transfer belt <NUM> therebetween. Then when the recording material P passes the transfer nip portion, bias is applied to the secondary transfer roller <NUM> from a high voltage power supply (not illustrated). Thereby a full color toner image is secondarily transferred from the surface of the intermediate transfer belt <NUM> to the recording material P which is passing through the transfer nip portion.

The recording material P bearing the toner is conveyed to a fixing portion (image heating portion). The fixing portion includes a heating unit <NUM> where a heater is disposed on the inner side of a flexible tubular film, and a pressure roller <NUM> which is disposed to face the heating unit <NUM>. The carried toner image is fixed to the recording material P by pressing the conveyed recording material P with heat in the fixing nip portion, which is constituted of the heating unit <NUM> and the pressure roller <NUM>. Then the recording material P is discharged out of the image forming apparatus <NUM> (arrow direction indicated in <FIG>) by a discharging roller <NUM>. In the present embodiment, the user operates the apparatus from the front side of the apparatus, hence the recording material P is discharged to a discharged paper stacking portion 11e, which is disposed on the front side of the apparatus, through a discharging port <NUM>, which is disposed on the rear side of the apparatus. In other words, the discharging direction of the recording material P is the same as the front-rear direction of the apparatus, that is, the downstream side in the discharging direction is the front side, and the upstream side, which is the opposite direction of the discharging direction, is the rear side. The recording material P is discharged through the discharging port <NUM> disposed on the rear side of the apparatus, and is stacked on the discharged paper stacking portion 11e, which is located on the front side of the apparatus at a lower position than the discharging port <NUM>, hence in this configuration, the user who performs operation from the front side of the apparatus can easily collect the recording material P.

<FIG> is a perspective view of the image forming apparatus <NUM> according to Embodiment <NUM> of the present invention viewed from the apparatus front side, and <FIG>is a perspective view thereof viewed from the apparatus rear side. The image forming apparatus <NUM> is covered by a cover <NUM>, which is a housing constituted of a plurality of members made of resin. In Embodiment <NUM>, the cover <NUM> is constituted of an upper cover <NUM>, a paper discharging cover <NUM>, a left cover <NUM>, a right cover <NUM>, a front door <NUM>, a cassette cover <NUM>, and a rear door <NUM>. The upper cover (top cover) <NUM> covers the top face side of the apparatus, and printed recording material is stacked on the discharged paper stacking portion 11e of the upper cover <NUM> via the discharging port <NUM> covered by the paper discharging cover <NUM>. On the upper cover <NUM>, an operation instructing portion <NUM>, which includes buttons for the user to instruct operation of the printer and a monitor to display the operation state of the apparatus, is disposed as an operation portion. In the configuration of Embodiment <NUM>, the user operates the apparatus from the front side of the apparatus, hence the operation instructing portion <NUM> is disposed on the front side of the apparatus, and the text to be displayed and the arrangement of the buttons are also designed based on the assumption that the user operates the operation instructing portion <NUM> from the front side. The front side of the apparatus is covered by the front door <NUM> and the cassette cover <NUM>.

The front door <NUM> is supported to be openable from the image forming apparatus <NUM>, so that such consumables as toner cartridges can be replaced. The cassette cover <NUM> is fixed to the feeding cassette <NUM>, and is supported so as to be withdrawable integrally with the feeding cassette <NUM> from the image forming apparatus main unit. By withdrawing the feeding cassette <NUM> from the image forming apparatus <NUM>, the user can replace or replenish the recording material P. Embodiment <NUM> has a configuration for the user to operate the apparatus from the apparatus front side, and the feeding cassette <NUM> can be withdrawn toward the apparatus front side. In other words, the inserting/withdrawing direction of the feeding cassette <NUM> is the same as the front-rear direction of the apparatus, and the downstream side in the withdrawing direction of the feeding cassette <NUM> corresponds to the front side of the apparatus. The left cover <NUM> covers the left side face of the image forming apparatus <NUM>, where an external connector portion 13a, to which a communication line from the outside (e.g. USB, wireless LAN) can be connected, is disposed on the apparatus rear side. The external connector portion 13a of Embodiment <NUM> includes a USB connector and a LAN connector, but may include other connectors. The right cover <NUM> covers the right side face of the image forming apparatus <NUM>, where a power supply connector portion 14a is disposed on the apparatus rear side. The rear door <NUM> is supported to be openable from the image forming apparatus <NUM>, so that a paper jam can be cleared and consumables can be replaced. The cover <NUM> may be constituted of more members, or may be one integrally formed component.

A positional relationship of a metal frame <NUM>, a wireless LAN module <NUM> and a control board <NUM> according to Embodiment <NUM> will be described with reference to <FIG> and <FIG>. <FIG> is a perspective view of an internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>. The frame <NUM> is disposed vertically, and includes a left frame (first metal side plate) <NUM> and a right frame (second metal side plate) <NUM>, which are a pair of side plates facing each other. The frame <NUM> also includes a front frame <NUM>, a rear frame <NUM> and a lower frame <NUM>, which are disposed between the left frame <NUM> and the right frame <NUM>. The front frame <NUM>, the rear frame <NUM> and the lower frame <NUM> are disposed in a direction orthogonal to the surfaces of the left frame <NUM> and the right frame <NUM>, so as to connect the left frame <NUM> and the right frame <NUM>. The left frame <NUM> and the right frame <NUM> extend horizontally from one end (front end) to the other end (rear end) of the apparatus along the front-rear direction of the apparatus, and are disposed to face each other across an image forming portion to form images and a discharging port <NUM> to discharge a recording material P to the outside. The configuration of the frame to implement the effect of the present invention is not limited to the present configuration, and may be modified in various ways.

The control board <NUM>, to control the operation of the image forming apparatus <NUM>, is installed on the left frame <NUM>. The control board <NUM> may be installed on the left frame <NUM> directly or installed via a mounting metal plate. The wireless LAN module <NUM>, which is a wireless communication board, includes an antenna 30a, and is held on the upper cover <NUM>. The wireless LAN module <NUM> receives predetermined instructions, such as printing and setting, from an external device via wireless LAN communication. The instruction received by the wireless LAN module <NUM> is transferred to the control board <NUM> via a flat cable <NUM> connected to a connector 31a. The control board <NUM> processes external information received by the wireless LAN module <NUM>, and sends the external information to a transmitting portion of the image forming apparatus <NUM>. The control board <NUM> includes a connector for external connection 31b. For the wireless LAN module, a Wi-Fi module, for example, can be used. The positional relationships of the wireless LAN module <NUM> and other components, which is a configuration characterizing the present invention, will be described later.

<FIG> is a left side view of the internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>. In order to stack the recording material P, which is discharged from the apparatus rear side to the apparatus front side, onto the discharged paper stacking portion 11e, the left frame <NUM> is formed such that the rear side of the apparatus, where the discharging port <NUM> is disposed, is located at a position higher than the apparatus front side where the discharged paper stacking portion 11e is disposed. In other words, the front side of the left frame <NUM> extends inclined, so that the height gradually decreases from the apparatus front side to the apparatus rear side, and the rear side of the left frame <NUM> extends horizontally at a position that is vertically higher than the upper end of the inclined portion on the front side of the left frame <NUM>, and is located on the rear side in the horizontal direction. The right frame <NUM> is formed in the same way as the left frame <NUM>.

The positional relationship of the wireless LAN module <NUM> and the frame <NUM> according to Embodiment <NUM> will be described in detail. The wireless LAN module <NUM> is held on the upper cover <NUM>. The wireless LAN module <NUM> is disposed such that the upper end of the left frame <NUM> in a region on the apparatus front side with respect to the wireless LAN module <NUM>, is located at a position vertically lower than the wireless LAN module <NUM>. Other components constituting the frame <NUM>, such as the right frame <NUM> and the front frame <NUM>, are also located at positions lower than the wireless LAN module <NUM> in the region on the apparatus front side, just like the left frame <NUM>. In other words, as indicated by the dotted line in <FIG>, the frame <NUM> in the region on the apparatus front side with respect to the wireless LAN module <NUM> is located vertically at a position lower than the wireless LAN module <NUM>. This configuration prevents a drop in communication performance in the apparatus front side with respect to the wireless LAN module <NUM>, due to the use of the metal frame <NUM>, hence good wireless communication performance can be ensured. This configuration is especially effective for image forming apparatuses similar to Embodiment <NUM>, which is based on the assumption that the user performs operation and wireless communication from the apparatus front side. Furthermore, the wireless LAN module <NUM> is disposed such that the surface of the board faces in the vertical direction, which means that the height of the apparatus does not become unnecessarily high. As a result, if this configuration is used, the apparatus size need not be increased.

Next the positional relationship of the wireless LAN module <NUM> and the control board <NUM> according to Embodiment <NUM> will be described in detail. The control board <NUM> is disposed near the upper end of the left frame <NUM> on the rear side, and is connected to the wireless LAN module <NUM> via the flat cable <NUM> connected to the connector 31a. The control board <NUM> is disposed so as to overlap with the metal left frame <NUM>, whereby noise resistance improves. The wireless LAN module <NUM> of the present embodiment is disposed at a position closer to the edge of the left frame <NUM> on the apparatus rear side than to the edge thereof on the apparatus front side, so as to be disposed at a position closer to the control board <NUM>. Further, the rear side of the left frame <NUM> of the Embodiment <NUM> is formed to become higher than the front side, hence the control board <NUM> can be disposed at a position close to the wireless LAN module <NUM> even in the vertical direction as well. Since the short flat cable <NUM> can be used as a cable connecting portion to connect the control board <NUM> and the wireless LAN module <NUM>, the connection operation becomes easy. Further, the short flat cable <NUM> increases noise resistance, which is advantageous in terms of wireless communication performance as well.

As described above, in order to ensure good wireless communication performance of the antenna 30a included in the wireless LAN module <NUM>, the left frame <NUM> is located at a position lower than the wireless LAN module <NUM> in a region on the apparatus front side with respect to the wireless LAN module <NUM>. The apparatus rear side of the left frame <NUM> is formed to be located at a position higher than the apparatus front side, and the wireless LAN module <NUM> and the control board <NUM> can be disposed close to each other, because the control board <NUM> disposed on the apparatus rear side is located higher. Because of this configuration, not only a drop in wireless communication performance due to the metal components but also a drop in wireless communication performance due to the use of the long cable connecting portion can be prevented at the same time.

A support portion of the upper cover <NUM> according to Embodiment <NUM> will be described with reference to <FIG>. <FIG> is a top view of the internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>. In order to support the upper cover <NUM> made of resin, the left frame <NUM> includes a support surface 21a and a securing portion 21b, and the front frame <NUM> includes a support surface 23b. Similar support surfaces to the left frame <NUM> are also disposed on the right frame <NUM>. The support surface 21a is located on the apparatus rear side with respect to the wireless LAN module <NUM>, and the securing portion 21b and the support surface 23b are located on the apparatus front side with respect to the wireless LAN module <NUM>.

<FIG> is a top view of the image forming apparatus <NUM> according to Embodiment <NUM>. <FIG> is a cross-sectional view at A-A in <FIG>, where only major components of the image forming apparatus <NUM> according to Embodiment <NUM> are indicated. The upper cover <NUM> holds the wireless LAN module <NUM> using the wireless LAN module holding portion 11d. The upper cover <NUM> includes support portions 11a, 11b and 11c, which are made of resin and extend downward in the apparatus, and is supported on the frame <NUM> by the support portions 11a, 11b and 11c. In Embodiment <NUM>, the support portions 11a, 11b and 11c are integrated with the upper cover <NUM>, but may be secured to the upper cover <NUM> as separate members. The support portion 11a is disposed in a region on the apparatus rear side with respect to the wireless LAN module holding portion 11d, and contacts the support surface 21a of the left frame <NUM>. Further, on the left frame <NUM>, a support member <NUM>, which is made of resin and includes a securing portion 26a and a support surface 26b, is secured by the securing portion 21b, and the support portion 11b, which is disposed on the apparatus front side with respect to the wireless LAN module holding portion 11d, contacts the support surface 26b. A support member <NUM> includes an opening portion through which a flat cable passes, and engages with the left frame <NUM>, so as to support the upper cover <NUM>, and partially contributes to holding the flat cable. Furthermore, the left frame <NUM> is connected with the front frame <NUM> by a connecting portion 21c, and the support portion 11c contacts the support surface 23b of the front frame <NUM>. This configuration is also the same in the apparatus right side. In other words, the upper cover <NUM> is supported by the left frame <NUM> and the right frame <NUM> directly or via another member. Since the upper cover <NUM> is supported on the frame <NUM> by a plurality of support portions, load is distributed, and the upper cover <NUM> can be stably supported.

In the region on the apparatus front side with respect to the wireless LAN module <NUM>, the securing portion 21b and the support surface 23b are disposed at positions lower than the wireless LAN module <NUM>, and the upper cover <NUM> is supported by the frame <NUM> via the support portions. The support portions 11a, 11b and 11c of the upper cover <NUM> and the support member <NUM> are made of resin, which can suppress a drop in wireless communication performance compared with the case of a metal frame that is disposed at the same height as the antenna 30a. In other words, a good communication performance of the apparatus can be maintained, since the securing portion 21b and the support surface 23b, which are located on the apparatus front side with respect to the wireless LAN module <NUM>, are both disposed at positions lower than the wireless LAN module <NUM>. Because of this configuration, good communication performance can be ensured while supporting the upper cover <NUM> with the metal frame.

In the present embodiment, the "apparatus front side" means the downstream side in the discharging direction of the recording material P, the withdrawing side in the inserting/withdrawing directions of the feeding cassette <NUM>, or the side on which the operation instructing portion <NUM> is disposed (second end side) in the direction where the left frame <NUM> extends horizontally. The "apparatus rear side" means the side on which the control board <NUM> is disposed (first end side) in the direction where the left frame <NUM> extends horizontally. In other words, the apparatus is configured based on the assumption that the user performs each of such an operation as collecting the recording material P, withdrawing the feeding cassette <NUM>, and operating the operation instructing portion <NUM> in a position facing the front side of the apparatus. On the other hand, components which are not usually operated, such as the control board <NUM> having the connector for external connection 31b, are disposed on the apparatus rear side.

In terms of the wireless communication performance alone, a drop in the wireless communication performance can be suppressed if the entire frame is made of resin, for example. However a resin frame is not as rigid as the case of using a metal frame, and is not very reliable to support the image forming portion and the discharging port <NUM>. An advantage of the configuration of the present invention is that rigidity of the apparatus is ensured using the metal frame, while a drop in the wireless communication performance due to the use of a metal component is prevented, and good wireless communication performance is ensured. In other words, in a region on the apparatus front side with respect to the wireless LAN module <NUM>, the upper end of the frame <NUM> is located lower than the wireless LAN module <NUM>, whereby the image forming apparatus that can ensure good communication performance can be provided while maintaining rigidity of the apparatus.

A configuration of an image forming apparatus <NUM> according to Embodiment <NUM> of the present invention will be described next with reference to <FIG> to <FIG>. A same composing element as Embodiment <NUM> is denoted with a same reference sign, and description thereof will be omitted.

<FIG> is a perspective view of the image forming apparatus <NUM> according to Embodiment <NUM> of the present invention viewed from the apparatus front side, and <FIG> is a perspective view thereof viewed from the apparatus rear side. The image forming apparatus <NUM> is covered by a cover <NUM>, which is an exterior constituted of an upper cover <NUM>, the paper discharging cover <NUM>, the left cover <NUM>, the right cover <NUM>, the front door <NUM>, the cassette cover <NUM> and the rear door <NUM>, and an original reading portion <NUM> is disposed above the upper cover <NUM>. In the original reading portion <NUM>, the image forming apparatus can read an image, such as an original provided by the user. The read image can be uploaded for printing, or as electronic data. The upper cover <NUM> covers the top face side of the apparatus, and printed recording material is stacked on the discharged paper stacking portion 211e of the upper cover <NUM> via the discharging port <NUM> covered by the paper discharging cover <NUM>. The upper cover <NUM> further includes reading portion support portions 211f and <NUM> on the left and right sides thereof, so as to support both ends of the original reading portion <NUM>.

A positional relationship of the metal frame <NUM>, the wireless LAN module <NUM>, and the control board <NUM> according to Embodiment <NUM> will be described with reference to <FIG> and <FIG>. <FIG> is a perspective view of an internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>. The frame <NUM> is constituted of the left frame <NUM>, the right frame <NUM>, the front frame <NUM>, the rear frame <NUM> and the lower frame <NUM>, just like Embodiment <NUM>, and the left frame <NUM> and the right frame <NUM> are connected by the front frame <NUM>, the lower frame <NUM> and the rear frame <NUM>. The wireless LAN module <NUM> is held on the upper cover <NUM>, and is connected to the control board <NUM> installed on the left frame <NUM> via the flat cable <NUM>.

The positional relationship of the wireless LAN module <NUM> and the frame <NUM> according to Embodiment <NUM> will be described in detail. <FIG> is a left side view of the internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>. The wireless LAN module <NUM> is held on the upper cover <NUM>. The wireless LAN module <NUM> is disposed such that an upper end of the left frame <NUM> in a region on the apparatus front side with respect to the wireless LAN module <NUM> is located at a position vertically lower than the wireless LAN module <NUM>. Other components constituting the frame <NUM>, such as the right frame <NUM> and the front frame <NUM>, are also located at positions lower than the wireless LAN module <NUM> in the region on the apparatus front side, just like the left frame <NUM>. In other words, as indicated by the dotted line in <FIG>, the frame <NUM> in the region on the apparatus front side with respect to the wireless LAN module <NUM> is located vertically at a position lower than the wireless LAN module <NUM>. This configuration prevents a drop in the communication performance on the apparatus front side of the wireless LAN module <NUM>, due to the use of the metal frame <NUM>, hence good wireless communication performance can be ensured. This configuration is especially effective for image forming apparatuses similar to Embodiment <NUM>, which is based on the assumption that the user performs operation and wireless communication from the apparatus front side. Furthermore, the wireless LAN module <NUM> according to Embodiment <NUM> is disposed such that the surface of the board is parallel with the surface of the left frame <NUM>, in order to prevent interference between the wireless LAN module <NUM> and the reading portion support portion 211f. In other words, the wireless LAN module <NUM> is disposed adjacent to the reading portion support portion 211f of the upper cover <NUM>, and various components are disposed such that the size of the apparatus does not become unnecessarily large. As a result, if this configuration is used, the apparatus size need not be increased.

Next the positional relationship of the wireless LAN module <NUM> and the control board <NUM> according to Embodiment <NUM> will be described in detail. In Embodiment <NUM> as well, the control board <NUM> is disposed near the upper end of the left frame <NUM> on the rear side, and is connected to the wireless LAN module <NUM> via the flat cable <NUM> connected to the connector 31a. Since the short flat cable <NUM> can be used to connect the control board <NUM> and the wireless LAN module <NUM>, the cable connecting portion becomes easy. Further, the short cable connecting portion increases noise resistance, hence this configuration is advantageous in terms of wireless communication performance as well.

The support portion of the upper cover <NUM> according to Embodiment <NUM> will be described with reference to <FIG>. <FIG> is a top view of the internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>. In order to support the upper cover <NUM>, the left frame <NUM> includes the support surface 21a and the securing portion 21b, and the front frame <NUM> includes the support surface 23b. Similar support surfaces to the left frame <NUM> are also disposed on the right frame <NUM>. The support surface 21a is located on the apparatus rear side with respect to the wireless LAN module <NUM>, and the securing portion 21b and the support surface 23b are located on the apparatus front side with respect to the wireless LAN module <NUM>.

<FIG> is a top view of the image forming apparatus <NUM> according to Embodiment <NUM>. <FIG> is a cross-sectional view at B-B in <FIG>, where only major components of the image forming apparatus <NUM> according to Embodiment <NUM> are indicated. The upper cover <NUM> holds the wireless LAN module <NUM> using a wireless LAN module holding portion 211d. The upper cover <NUM> includes support positions 211a, 211b and 211c, which are made of resin and extend downward in the apparatus, and is supported on the frame <NUM> by the support portions 211a, 211b and 211c, just like Embodiment <NUM>. In other words, the upper cover <NUM> is supported on the left frame <NUM> and the right frame <NUM> directly or via another member, such as the support member <NUM>. In Embodiment <NUM>, the support portions 211a, 211b and 211c are formed integrally with the upper cover <NUM>, but may be secured to the upper cover <NUM> as separate members. The upper cover <NUM> of Embodiment <NUM> further includes the reading portion support portions 211f and <NUM>, and supports the original reading portion <NUM> disposed above.

In Embodiment <NUM> as well, in the region on the apparatus front side with respect to the wireless LAN module <NUM>, the securing portion 21b and the support surface 23b are disposed at positions lower than the wireless LAN module <NUM>, and the upper cover <NUM> is supported by the frame <NUM> via the support portions. The support portions 211a, 211b and 211c of the upper cover <NUM> and the support member <NUM> are made of resin, which can suppress a drop in the wireless communication performance compared with the case of a metal frame that is disposed at the same height as the antenna 30a. In other words, good communication performance of the apparatus can be maintained, since the securing portion 21b and the support surface 23b, which are located on the apparatus front side with respect to the wireless LAN module <NUM>, are both disposed at positions lower than the wireless LAN module <NUM>. Because of this configuration, good wireless communication performance can be ensured while supporting the upper cover <NUM> with the metal frame.

By the above configuration, even in Embodiment <NUM> which includes the original reading portion <NUM>, the upper end of the frame <NUM> can be located at a position lower than the wireless LAN module <NUM> in the region on the apparatus front side with respect to the wireless LAN module <NUM>. In other words, the image forming apparatus that can ensure good communication performance can be provided while maintaining rigidity of the apparatus.

A configuration of an image forming apparatus <NUM> according to Embodiment <NUM> of the present invention will be described next with reference to <FIG> to <FIG>. A same composing element as Embodiment <NUM> or Embodiment <NUM> is denoted with a same reference sign, and description thereof will be omitted.

<FIG> is a perspective view of the image forming apparatus <NUM> according to Embodiment <NUM> of the present invention viewed from the apparatus front side, and <FIG> is a perspective view thereof viewed from the apparatus rear side. The image forming apparatus <NUM> is covered by a cover <NUM>, which is an exterior constituted of an upper cover <NUM>, the paper discharging cover <NUM>, the left cover <NUM>, the right cover <NUM>, the front door <NUM>, the cassette cover <NUM> and the rear door <NUM>. The upper cover <NUM> covers the top face side of the apparatus, and printed recording material is stacked on a discharged paper stacking portion 311e of the upper cover <NUM> via the discharging port <NUM> covered by the paper discharging cover <NUM>. The upper cover <NUM> includes a horizontal surface 311f and an inclined surface <NUM>, and the power switch <NUM> and the operation instructing portion <NUM> are disposed as an operation portion on the inclined surface <NUM> located on the apparatus front side. The user turns the power ON/OFF using the power switch <NUM> (switch portion), and operates the printer using the operation instructing portion <NUM> which includes operation buttons to instruct operation of the printer and a monitor to display the operation state of the apparatus.

A positional relationship of the frame <NUM>, the wireless LAN module <NUM>, the control board <NUM>, the power switch <NUM> and the operation instructing portion <NUM> according to Embodiment <NUM> will be described with reference to <FIG>. <FIG> is a perspective view of an internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>. The frame <NUM> is constituted of the left frame <NUM>, the right frame <NUM>, the front frame <NUM>, the rear frame <NUM> and the lower frame <NUM>, just like Embodiment <NUM>, and the left frame <NUM> and the right frame <NUM> are connected by the front frame <NUM>, the lower frame <NUM> and the rear frame <NUM>. The wireless LAN module <NUM> is held on the upper cover <NUM>, and is connected to the control board <NUM> installed on the left frame <NUM> via the flat cable <NUM>. In Embodiment <NUM>, an intermediate control board <NUM> is installed on the left frame <NUM> in addition to the control board <NUM>. The intermediate control board <NUM> is connected to the control board <NUM> via a flat cable <NUM>, connected to the power switch <NUM> via a flat cable <NUM>, and is connected to the operation instructing portion <NUM> via a flat cable <NUM>. The types and routes of the connection lines are not limited to the present configuration, but may be modified in various ways.

The positional relationship of the wireless LAN module <NUM> and the frame <NUM> according to Embodiment <NUM> will be described in detail. <FIG> is a left side view of the internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>, and indicates the wireless LAN module <NUM> and the power switch <NUM>. The wireless LAN module <NUM> is held on the upper cover <NUM>. The wireless LAN module <NUM> is disposed such that an upper end of the left frame <NUM> in a region on the apparatus front side with respect to the wireless LAN module <NUM> is located at a position vertically lower than the wireless LAN module <NUM>. Other components constituting the frame <NUM>, such as the right frame <NUM> and the front frame <NUM>, are also located at positions lower than the wireless LAN module <NUM> in the region on the apparatus front side, just like the left frame <NUM>. In other words, as indicated by the dotted line in <FIG>, the frame <NUM> in the region on the apparatus front side with respect to the wireless LAN module <NUM> is located at a position vertically lower than the wireless LAN module <NUM> in the vertical direction. This configuration prevents a drop in communication performance on the apparatus front side with respect to the wireless LAN module <NUM>, due to the use of the metal frame <NUM>, hence good wireless communication performance can be ensured. This configuration is especially effective for image forming apparatuses similar to Embodiment <NUM>, which is based on the assumption that the user performs operation and wireless communication from the apparatus front side.

Next the positional relationship of the wireless LAN module <NUM> and the power switch <NUM> according to Embodiment <NUM> will be described in detail. In Embodiment <NUM>, the power switch <NUM> is disposed in the region on the apparatus front side with respect to the wireless LAN module <NUM>, and is positioned at a position vertically lower than the wireless LAN module <NUM>. In other words, a drop in the communication performance of the wireless LAN module <NUM> in the front side of the apparatus, due to the presence of the power switch <NUM> which include metal components, is prevented. The power switch <NUM> is constituted of such components as a switch pressing portion 2a, a switch board 2b, a switch holder 2c, and a switch connector 2d. At least the switch board 2b and the switch connector 2d contain metal, hence it is particularly critical that these components are located at positions lower than the wireless LAN module <NUM>.

Next the positional relationship of the wireless LAN module <NUM> and the operation instructing portion <NUM> according to Embodiment <NUM> will be described in detail. <FIG> is a left side view of the internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>, and indicates the wireless LAN module <NUM> and the operation instructing portion <NUM>. In Embodiment <NUM>, the operation instructing portion <NUM> is disposed in the region on the apparatus front side with respect to the wireless LAN module <NUM>, and is located at a position vertically lower than the wireless LAN module <NUM>. In other words, a drop in communication performance on the apparatus front side with respect to the wireless LAN module <NUM>, due to the presence of the operation instructing portion <NUM> which includes metal components, is prevented. Further, the flat cable <NUM> connecting the operation instructing portion <NUM> and the control board <NUM> is also disposed at a position lower than the wireless LAN module <NUM>, so as to prevent a drop in wireless communication performance on the apparatus front side.

Next the positional relationship of the wireless LAN module <NUM> and the control board <NUM> according to Embodiment <NUM> will be described in detail. In Embodiment <NUM> as well, the control board <NUM> is disposed near the upper end of the left frame <NUM> on the rear side, and is connected to the wireless LAN module <NUM> via the flat cable <NUM> connected to the connector 31a. Since the short flat cable <NUM> can be used to connect the control board <NUM> and the wireless LAN module <NUM>, operation of connecting the cable connecting portion becomes easy. Further, the short cable connection portion increases noise resistance, which is advantageous in terms of wireless communication performance as well.

<FIG> is a top view of the image forming apparatus <NUM> according to Embodiment <NUM>. <FIG> is a cross-sectional view of an internal configuration at C-C in <FIG>, where only major components of the image forming apparatus <NUM> including the upper cover <NUM> according to Embodiment <NUM> are indicated. The upper cover <NUM> holds the wireless LAN module <NUM> by a wireless LAN holding portion 311d. The upper cover <NUM> includes support portions 311a and <NUM>1b, which are made of resin and extend downward in the apparatus, and is supported on the frame <NUM> by the support portions 311a and 311b, just like Embodiment <NUM>. In other words, the upper cover <NUM> is supported on the left frame <NUM> and the right frame <NUM> directly or via another member, such as the support member <NUM>.

In Embodiment <NUM> as well, in the region on the apparatus front side with respect to the wireless LAN module <NUM>, the securing portion 21b and the support surface 23b are disposed at positions lower than the wireless LAN module <NUM>, and the upper cover <NUM> is supported by the frame <NUM> via the support portions. The support portions 311a and 311b of the upper cover <NUM> and the support member <NUM> are made of resin, which can suppress a drop in wireless communication performance compared with the case of a metal frame that is disposed at the same height as the antenna 30a. In other words, good communication performance of the apparatus can be maintained, since the securing portion 21b and the support surface 23b, which are located on the apparatus front side with respect to the wireless LAN module <NUM>, are both disposed at positions lower than the wireless LAN module <NUM>. Because of this configuration, good wireless communication performance can be ensured while supporting the upper cover <NUM> with the metal frame.

By the above configuration, in the region on the apparatus front side with respect to the wireless LAN module <NUM>, the frame <NUM>, the power switch <NUM> and the operation instructing portion <NUM> can be disposed at positions lower than the wireless LAN module <NUM>. In other words, the image forming apparatus that can ensure good communication performance can be provided while maintaining rigidity of the apparatus.

A configuration of an image forming apparatus <NUM> according to Embodiment <NUM> not forming part of the invention but useful for understanding the invention will be described next with reference to <FIG>.

In Embodiment <NUM>, a case where some features of the present invention are applied to a monochrome laser beam printer, which can form monochrome images using an electrophotographic system, will be described. Application of the present invention is not limited to this, and the present invention is also applicable to such printers using a color tandem recording system, described in the above embodiments, and copiers, printers and the like using an electrostatic recording system or inkjet recording system.

In Embodiment <NUM> as well, directions are defined with respect to the user who is using the image forming apparatus <NUM>. In other words, in a state of using the image forming apparatus <NUM>, front side (front face side) of the image forming apparatus <NUM> that the user is facing is "front", rear face side (back side) "rear", upper face side (top face side) is "up", and lower face side (bottom face side) is "down". The left side face side of the image forming apparatus <NUM>, when the image forming apparatus <NUM> is viewed from the front face side, is "left", and the right side face side thereof is "right".

<FIG> is a schematic cross-sectional view from the left side face side depicting a general configuration of the image forming apparatus <NUM> according to Embodiment <NUM> of the present invention. The image forming apparatus <NUM> includes an image forming portion and a fixing portion supported by the metal frame <NUM>, and forms monochrome images.

The image forming portion includes a photosensitive drum <NUM> (image bearing member), a charging roller <NUM>, a developing roller <NUM>, and a toner container <NUM>. The image forming portion may have a configuration of a process cartridge, which is integrally detachable from the apparatus. When image information is received and the image forming operation is started, the photosensitive drum <NUM> is rotated. First the outer peripheral surface of the photosensitive drum <NUM> is uniformly charged by the charging roller <NUM>, and the charged surface is irradiated with a laser beam from a laser scanner <NUM> in accordance with the image information, so as to form an electrostatic latent image. The latent image becomes visible by the developing roller <NUM>, whereby a toner image is formed on the surface of the photosensitive drum. A sheet type recording material P, which is stored in a feeding cassette <NUM> disposed in a lower portion of the image forming apparatus <NUM> before forming an image, is separated and fed one-by-one from the feeding cassette <NUM> to a resist roller pair <NUM> by a feeding roller <NUM>. The resist roller pair <NUM> conveys the recording material P which was fed into a transfer nip portion between a transfer roller <NUM> and the photosensitive drum <NUM>. Then when the recording material P passes through the transfer nip portion, bias is applied to the transfer roller <NUM> from an electric unit <NUM>. Thereby a monochrome toner image is transferred from the surface of the photosensitive drum <NUM> to the recording material P which is passing through the transfer nip portion.

The recording material P bearing the toner is conveyed to a fixing portion (image heating portion). The fixing portion includes a heating unit <NUM> where a heater is disposed on the inner side of a flexible tubular film, and a pressure roller <NUM> which is disposed to face the heating unit <NUM>. The carried toner image is fixed to the recording material P with heat in the fixing nip portion, which is constituted of the heating unit <NUM> and the pressure roller <NUM>. Then the recording material P is discharged out of the image forming apparatus <NUM> (arrow R direction indicated in <FIG>) into the discharging tray <NUM> by a discharging roller <NUM>, through a discharging port <NUM>.

<FIG> is a perspective view of the image forming apparatus <NUM> according to Embodiment <NUM> viewed from the apparatus front side. The image forming apparatus <NUM> is covered by a cover <NUM>, which is a housing constituted of a plurality of members made of resin. In Embodiment <NUM>, the cover <NUM> is constituted of an upper cover <NUM>, a left cover <NUM>, a right cover <NUM>, a front cover <NUM>, a cassette cover <NUM>, a rear door <NUM>, an internal cover <NUM>, and a discharging tray <NUM>. The upper cover (top cover) <NUM> covers at least a part of the top face side of the apparatus, and on the cassette cover <NUM>, an operation instructing portion <NUM>, which is an operation portion for the user to instruct operation of the printer, is disposed. The operation instructing portion <NUM> is located on the front side of the image forming apparatus <NUM>, and includes operation buttons 403a for the user to instruct operation of the printer, and a monitor 403b to display the operation state of the apparatus.

A positional relationship of a frame <NUM>, a wireless LAN module <NUM>, a control board <NUM> and an operation instructing portion <NUM> according to Embodiment <NUM> will be described with reference to <FIG>. <FIG> is a perspective view of an internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>, <FIG> is a left side view thereof, and <FIG> is a top view thereof. The frame <NUM> is disposed vertically, and includes a left frame <NUM> and a right frame <NUM>, which are a pair of side plates facing each other. The frame <NUM> also includes a front frame <NUM>, a rear frame <NUM> and a lower frame <NUM>, which are disposed between the left frame <NUM> and the right frame <NUM>. The front frame <NUM>, the rear frame <NUM> and the lower frame <NUM> are disposed in a direction orthogonal to the surfaces of the left frame <NUM> and the right frame <NUM>, so as to connect the left frame <NUM> and the right frame <NUM>. The frame <NUM> also includes a lower left frame <NUM> and the lower right frame <NUM>, which are made of resin, and the lower left frame <NUM> supports the left frame <NUM>, and the lower right frame <NUM> supports the right frame <NUM>. In Embodiment <NUM>, in the front-rear direction, the right frame <NUM> is formed such that a rear upper face 422a located on the rear side is at a position higher than a front upper face 422b located on the front side. In other words, on the rear side where communication performance is not very critical as on the front side, the height of the frame <NUM> is increased to shorten the distance to the upper cover <NUM>, so that the upper cover <NUM> can be more firmly supported. An upper face 421a, which is the upper end of the left frame <NUM>, is located at a position even lower than a front upper face 422b of the right frame <NUM>.

The image forming apparatus <NUM> according to Embodiment <NUM> further includes a support member <NUM> which is made of resin, and has a function to support the wireless LAN module <NUM> and a function to maintain the rigidity of the image forming apparatus. The support member <NUM> is secured on the upper face 421a of the left frame <NUM>. The wireless LAN module <NUM> is supported by the support member <NUM>, and is connected to the control board <NUM> which is installed on the left frame <NUM> via the flat cable <NUM>. The support member <NUM> is supported above the left frame <NUM>. In other words, the upper face 421a of the left frame <NUM> is located at a position vertically lower than the wireless LAN module <NUM>. Further, the front upper face 422b of the right frame <NUM> located on the apparatus front side with respect to the wireless LAN module <NUM> is also located at a position vertically lower than the wireless LAN module <NUM>. In other words, in a region on the apparatus front side with respect to the wireless LAN module <NUM>, the upper face 421a of the left frame <NUM> and the rear upper face 422a of the right frame <NUM> are both located at positions lower than the wireless LAN module <NUM>, hence good communication performance of the apparatus can be maintained.

The operation instructing portion <NUM> is disposed on the cassette cover <NUM> located at a position that is on the front side and the lower side of the apparatus, and is connected to the control board <NUM> via the flat cable <NUM>. In other words, the operation instructing portion <NUM>, which is located on the apparatus front side with respect to the wireless LAN module <NUM>, is disposed at a position lower than the wireless LAN module <NUM>. The type and route of each connection line and configuration of the frame are not limited to the configuration described above, but may be modified in various ways.

A support portion of the upper cover <NUM> according to Embodiment <NUM> will be described with reference to <FIG> is a cross-sectional view of the internal configuration of the image forming apparatus <NUM> according to Embodiment <NUM>, where only major components are indicated without the cover <NUM>, other than the upper cover <NUM>. The support member <NUM> disposed near the left end of the image forming apparatus <NUM> contacts the upper cover <NUM> at a rear support portion 428a, an intermediate support portion 428b and a front support portion 428c, and the left frame <NUM> supports the upper cover <NUM> via the support member <NUM>. In a region near the right end of the apparatus, a support portion (not illustrated), which extends downward from the upper cover <NUM>, contacts the front upper face 422b and the rear upper face 422a of the right frame <NUM>. The upper cover <NUM> is made of resin, and the support portions thereof are also made of resin. Therefore the upper cover <NUM> is supported by the left frame <NUM> and the right frame <NUM> via the support portions made of resin.

In Embodiment <NUM> as well, in the region on the apparatus front side with respect to the wireless LAN module <NUM>, the metal frame <NUM> is disposed at a position lower than the wireless LAN module <NUM>, and the upper cover <NUM> is supported by the frame <NUM> via the support member <NUM>. The upper cover <NUM> and the support member <NUM> are made of resin, and a drop in wireless communication performance can be suppressed compared with the case where the metal frame is disposed at a height the same as the antenna 430a. In other words, good communication performance of the apparatus can be maintained since the frame <NUM>, which is located on the apparatus front side with respect to the wireless LAN module <NUM>, is disposed at a position lower than the wireless LAN module <NUM>. Because of this configuration, good wireless communication performance can be ensured while supporting the upper cover <NUM> by the metal frame.

By of the above configuration, even in Embodiment <NUM> which includes the support member <NUM>, in the region on the apparatus front side with respect to the wireless LAN module <NUM>, the frame <NUM> and the operation instructing portion <NUM> can be disposed at positions lower than the wireless LAN module <NUM>. In other words, the image forming apparatus that can ensure good wireless communication performance can be provided while maintaining the rigidity of the apparatus.

In the above embodiments, the wireless LAN module, particularly the Wi-Fi module, was described as an example of the wireless communication board. However the present invention is not limited to this. A module of another communication system, such as near field communication (NFC) or Bluetooth may be used for the wireless communication board.

Claim 1:
An image forming apparatus (<NUM>) comprising:
an image forming portion configured to form an image on a recording material;
a first metal side plate (<NUM>) and a second metal side plate (<NUM>) disposed to sandwich the image forming portion;
a wireless communication board (<NUM>) including an antenna configured to communicate with an external device; and
a housing in which the image forming portion is disposed, wherein
the housing includes a top cover (<NUM>) that is disposed at a position vertically higher than the first metal side plate, the top cover contacts the first metal side plate and the second metal side plate, wherein
in a region on a downstream side with respect to the antenna in a discharging direction where a recording material, on which an image is formed by the image forming portion, is discharged from a discharging port (<NUM>) of the image forming apparatus, an upper end of the first metal side plate is located at a position vertically lower than the antenna, and a resin support portion connected to the first metal side plate is disposed in the region such that the resin support portion supports the top cover, and the antenna and the resin support portion are disposed along the upper end of the first metal side plate, and
wherein the wireless communication board is held on the top cover.