Image forming apparatus

Abstract

To provide an image forming apparatus that does not impair the sound leakage suppression function of the sound-absorbing material that seals the gaps between the outer covers, and that is less prone to bending of the outer covers caused by the sound-absorbing material. [Solution] A sound-absorbing material 322 with a slit 324 is used to seal the gap between the covers. The slit 324 is cut into the end face of the right end portion 322f of the sound-absorbing material 322 that is pressed by the cover. Because the slit 324 is formed in the sound-absorbing material 322, the repulsive force of the sound-absorbing material 322 that occurs in response to the pressing force received from the cover when the sound-absorbing material 322 is pressed by the cover can be reduced. When multiple slits 324 are formed side by side in the longitudinal direction, the area 322b sandwiched between the slits 324 elastically deforms without affecting the adjacent area 322c, so the repulsive force of the sound-absorbing material 322 that occurs in response to the pressing force received from the cover can be further reduced.

Description

Technical Field

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

Background Art

[0002] Image forming apparatuses such as printers, copiers, facsimile machines, or multifunction peripherals mainly have a plurality of exterior covers that constitute the exterior of the image forming apparatus from the viewpoint of designability of the appearance, and there may be a gap between adjacent exterior covers. In that case, if the gap remains open, the sound generated inside the apparatus during various operations performed to form an image on a recording material, including the conveyance of the recording material, leaks from the gap to the outside, and becomes a noisy sound that is annoying to the user who uses the image forming apparatus. Therefore, conventionally, as in the apparatus described in Patent Document 1, it has been proposed to suppress sound leakage to the outside by closing the gap between the exterior covers with a shielding material. As the shielding material, a sound-absorbing material such as a sponge having elasticity and absorbing sound is used.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in order to fill the gap so that sound does not leak, the sound-absorbing material needs to be adhered to the exterior covers, and therefore, at least a part of the sound-absorbing material is in a compressed state by the exterior covers. However, conventionally, depending on the strength and rigidity of the exterior covers and the elastic force of the sound-absorbing material, the repulsive force of the sound-absorbing material in the compressed state may cause the exterior covers to bend, and there is a risk that the designability of the appearance may be impaired.

[0005] In view of the above-mentioned problems, the present invention aims to provide an image forming apparatus in which, when the gap between outer covers is sealed with sound-absorbing material, the sound-absorbing material does not impair the sound leakage suppression function of the sound-absorbing material, and in which the bending of the outer cover caused by the sound-absorbing material is less likely to occur. [Means for solving the problem]

[0006] An image forming apparatus according to one embodiment of the present invention is an image forming apparatus for forming an image on a recording material, comprising: a first cover member that forms the exterior surface of the image forming apparatus; a second cover member disposed next to the first cover member and combined with the first cover member to form the exterior surface of the image forming apparatus; and a sound-absorbing material that at least partially seals the gap between the first cover member and the second cover member, wherein the sound-absorbing material has a slit cut from the end face of the end at the end of the second cover member. [Effects of the Invention]

[0007] According to the present invention, when the gap between outer covers is sealed with sound-absorbing material, it is possible to reduce the likelihood of the outer covers bending due to the sound-absorbing material without impairing the sound leakage suppression function of the sound-absorbing material. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic diagram showing an image forming system equipped with the image forming apparatus of this embodiment. [Figure 2] A perspective view showing an image forming apparatus equipped with a manual paper feed unit. [Figure 3] A side view showing an image forming apparatus without a manual paper feed unit installed. [Figure 4] A perspective view showing the right side cover facing the housing. [Figure 5] Schematic diagram showing cross-section AA in Figure 3. [Figure 6] A schematic diagram showing the right side cover, right side middle cover, and sound-absorbing material. [Figure 7] A top view showing the sound-absorbing material used in this embodiment. [Figure 8] A schematic diagram showing the manual feed tray, right side inner cover, and sound-absorbing material when the manual feed unit is installed. [Figure 9] This diagram illustrates the deflection of the right side cover that occurred when conventional sound-absorbing materials were used, showing (a) the case without sound-absorbing material and (b) the case with sound-absorbing material. [Modes for carrying out the invention]

[0009] <Image Forming System> The following describes this embodiment. First, the image forming system equipped with the image forming apparatus of this embodiment will be described with reference to Figure 1. As shown in Figure 1, the image forming system 100 has an image forming apparatus 1 and a finisher 80. The image forming apparatus 1 is a color image forming apparatus using an electrophotographic method. In this embodiment, an intermediate transfer tandem type image forming apparatus 1 is given as an example, due to its advantages in adaptability to a wide variety of sheets S and excellent print productivity, in which four color image forming units are arranged in a row above the intermediate transfer belt. The finisher 80 is connected to the image forming apparatus 1 afterwards to perform post-processing on the recording material on which an image has been formed by the image forming apparatus 1, such as stapling or saddle stitching. Various recording materials such as paper such as paper and envelopes, glossy paper, plastic films such as overhead projector sheets, and cloth can be used as the sheet S.

[0010] <Image forming apparatus> Next, the general configuration of the image forming apparatus 1 will be explained using Figures 1 and 2. As shown in Figure 1, the image forming apparatus 1 has a housing 1A. Although not shown in the figure, the housing 1A is composed of multiple sheet metal parts, such as front and rear plates provided at the front and rear to support each unit, and stays connecting these front and rear plates, and is surrounded by multiple exterior covers, which will be described later and constitute the exterior of the image forming apparatus 1.

[0011] The image forming apparatus 1 includes a sheet feeding unit 101 for feeding sheets S, and a sheet transport unit 109 for transporting the sheets S fed by the sheet feeding unit 101. In this embodiment, the sheet transport unit 101 and the sheet transport unit 109 constitute a sheet transport apparatus 2. The image forming apparatus 1 also includes an image forming unit 102 for forming images on the sheets S transported by the sheet transport unit 109.

[0012] The sheet feeding unit 101 includes a manual feed unit 30 capable of loading multiple sheets into a manual feed tray that opens from the side of the image forming apparatus 1, and paper feed cassettes 31, 32, and 33 capable of storing and loading multiple sheets. The sheet feeding unit 101 also includes a feed roller 35 for feeding the uppermost sheet S of the manual feed unit 30, and feed rollers 36, 37, and 38 for feeding the uppermost sheet S of the paper feed cassettes 31, 32, and 33. The manual feed unit 30 may be provided as an optional unit that can be retrofitted and detachably attached to the housing 1A.

[0013] The image forming unit 102 includes a photoreceptor 61 (61Y, 61M, 61C, 61K), a charger 62 (62Y, 62M, 62C, 62K), an exposure unit 63 (63Y, 63M, 63C, 63K), and a developer unit 64 (64Y, 64M, 64C, 64K). The image forming unit 102 also includes a primary transfer roller 66 (66Y, 66M, 66C, 66K) and a photoreceptor cleaner 65 (65Y, 65M, 65C, 65K). Furthermore, the image forming unit 102 includes an intermediate transfer belt 67 to which the toner image formed on the photoreceptors 61Y, 61M, 61C, 61K is transferred, and a secondary transfer roller 43 to which the toner image transferred on the intermediate transfer belt 67 is transferred to the sheet S. The intermediate transfer belt 67 is tensioned by rollers such as a drive roller 68, a tension roller 69, and a secondary transfer inner roller 70, and is rotated clockwise in the direction of arrow R in the figure. The image forming unit 102 also has a fuser 45 that fixes the image onto the sheet S on which the toner image has been transferred.

[0014] The sheet transport unit 109 has supply transport paths 40 and 41, which are sheet transport paths through which the sheets S, transported by the supply rollers 35 to 38, pass. The sheet transport unit 109 also has a register roller 42 that feeds the sheets S to the secondary transfer section N, which is the contact point between the intermediate transfer belt 67 and the secondary transfer roller 43. The sheet transport unit 109 also has a pre-fixing transport belt 44 that sends the sheets S, on which the toner image has been transferred, to the fuser 45. Downstream of the fuser 45 is a post-fixing transport path 59 equipped with an internal discharge roller 46. The sheet transport unit 109 also has a reversal section 85 downstream of the post-fixing transport path 59 in the transport direction of the sheets S that performs switchback transport of the sheets S. The post-fixing transport path 59 and the reversal section 85 are connected via a substantially horizontal outlet 59a of the post-fixing transport path 59.

[0015] The reversal section 85 includes a discharge transport path 51, a reversal guidance path 52, a switchback path 55, and a reversal discharge path 56. The discharge transport path 51, whose upstream end in the transport direction is connected to the post-fixing transport path 59, is a sheet transport path that guides the sheet S on which the image has been formed to be discharged from the image forming apparatus 1. The reversal guidance path 52, whose upstream end in the transport direction is connected to the post-fixing transport path 59, is a sheet transport path that branches off from the discharge transport path 51. The switchback path 55 is a sheet transport path into which the sheet that has passed through the reversal guidance path 52 is drawn in in order to reverse the front and back sides of the sheet S on which the image has been formed and the leading and trailing ends in the transport direction. The reversal discharge path 56 is a sheet transport path that merges with the discharge transport path 51 and guides the sheet S drawn into the switchback path 55 to be discharged from the image forming apparatus 1. The reversal section 85 also includes a pair of reversal upper rollers 53 and a pair of reversal lower rollers 54 provided within the switchback path 55. Furthermore, the reversing unit 85 has an external discharge roller 49 that transports the sheet S discharged from the fuser 45.

[0016] The sheet conveyance unit 109 also has a duplex conveyance path 47, which is a sheet conveyance path through which the sheet S whose conveyance direction has been reversed in the switchback path 55 of the reversing unit 85 is conveyed. The switchback path 55 and the duplex conveyance path 47 are connected via an entrance 47a of the substantially horizontal duplex conveyance path 47. The duplex conveyance path 47 is connected to the supply conveyance path 41. The sheet conveyance unit 109 also has duplex rollers 48a, 48b, 48c, and 48d that convey the sheet S passing through the duplex conveyance path 47.

[0017] [Sheet Conveyance Process] The sheet S is loaded in the manual paper feeding unit 30 or the paper feeding cassettes 31 to 33, and is fed by the respective paper feeding rollers 35 to 38 in accordance with the image formation timing in the image forming unit 102. The sheet S sent out by the respective paper feeding rollers 35 to 38 passes through the respective supply conveyance paths 40 and 41, and is conveyed to the registration roller 42.

[0018] When the conveyed sheet S abuts against the registration roller 42, the registration roller 42 forms a loop of the sheet S. Thereby, the leading end of the sheet S follows the registration roller 42, and the skew of the sheet S is corrected. After correcting the skew of the sheet S, the registration roller 42 sends out the sheet S to the secondary transfer unit N at a predetermined timing in accordance with the image formation timing on the sheet S. That is, the registration roller 42 conveys the sheet S to the secondary transfer unit N in accordance with the timing when the toner image carried on the intermediate transfer belt 67 comes to the secondary transfer unit N.

[0019] The secondary transfer unit N is a nip portion formed by a secondary transfer inner roller 70 and a secondary transfer roller 43 that are arranged to face each other via the intermediate transfer belt 67, and transfers the toner image to the sheet S. In the secondary transfer unit N, a predetermined pressing force and an electrostatic load bias are applied, whereby the toner image is secondarily transferred onto the sheet S.

[0020] [Image Formation Process] The image formation process, which takes place at the same time as the sheet transport process up to the secondary transfer section N described above, will now be explained. First, the surface of the rotating photoreceptor 61 is uniformly charged by the charger 62. The charged surface of the photoreceptor 61 is then scanned and exposed by the exposure unit 63. The exposure unit 63 is driven based on the image information signal that has been sent. This forms an electrostatic latent image on the photoreceptor 61. The electrostatic latent image formed on the photoreceptor 61 is developed by the developer unit 64 using a developer containing toner, thereby forming a toner image on the photoreceptor 61. The toner image on the photoreceptor 61 is then applied to the intermediate transfer belt 67 by the primary transfer roller 66, which applies a predetermined pressure and electrostatic load bias. After the primary transfer process, any toner remaining on the photoreceptor 61 (transfer residue toner) is removed and recovered from the photoreceptor 61 by the photoreceptor cleaner 65.

[0021] When forming a full-color image, the above image formation process is performed for each of the yellow (Y), magenta (M), cyan (C), and black (K) toners. The toner images of each color—yellow, magenta, cyan, and black—formed on each photoreceptor 61 are then transferred to the intermediate transfer belt 67 in a superimposed manner. This forms the toner image for the full-color image on the intermediate transfer belt 67. The image forming apparatus 1 can also form monochrome images, such as a single black image.

[0022] As described above, in the secondary transfer section N, the toner image is transferred from the intermediate transfer belt 67 onto the sheet S. The sheet S is then transported to the fuser 45 by the pre-fixing transport belt 44. The fuser 45 fixes the toner image onto the sheet S using a predetermined pressure applied by opposing rollers or belts and heat from a heat source such as a heater.

[0023] The sheet S, on which the image has been fixed, is transported by the internal discharge roller 46 within the post-fixing transport path 59 and sent to either the discharge transport path 51 or the reversal guide path 52. A switching unit (not shown) is located at the branching point between the discharge transport path 51 and the reversal guide path 52 to selectively switch the transport path of the sheet S. When the sheet S is to be discharged from the image forming apparatus 1, the discharge transport path 51 is selected by the switching unit. When the front and back sides and the leading and trailing ends in the transport direction of the sheet S are reversed before discharge from the image forming apparatus 1, or when an image is to be formed on the back side (second side) of the sheet S during double-sided image formation, the reversal guide path 52 is selected by the switching unit.

[0024] The sheet S, transported through the discharge transport path 51 by the internal discharge roller 46, is discharged from the image forming apparatus 1 by the external discharge roller 49. The buffer path 81 of the buffer path unit 181 of the finisher 80, which will be described later, is connected to the discharge transport path 51. The sheet S transported by the external discharge roller 49 is sent to the post-processing unit 108 via the buffer path 81, where post-processing is performed as needed. Finally, the sheet S is discharged to one of the discharge loading sections 83a, 83b, 83c, or 83d of the finisher 80.

[0025] When forming an image on the back side (second side) of sheet S during double-sided image formation, sheet S, transported within the inversion guidance path 52, is carried by the inversion upper roller pair 53 and the inversion lower roller pair 54 and pulled into the switchback path 55. Once pulled into the switchback path 55, the rotation direction of the inversion lower roller pair 54 is switched to the opposite direction from when it was pulled in, thereby reversing the leading and trailing ends of the transport direction (so-called switchback). Then, sheet S is transported to the double-sided transport path 47 by the inversion lower roller pair 54. Subsequently, sheet S is transported within the double-sided transport path 47 by the double-sided rollers 48a to 48d and, in conjunction with the subsequent sheet S being transported by the feed rollers 35 to 38, is brought into the supply transport path 41. Then, sheet S is sent to the secondary transfer section N via the resist roller 42. The image formation process for the back side (second side) of sheet S is the same as that for the front side (first side) described above, so the explanation is omitted.

[0026] When the front and back sides and the leading and trailing ends in the transport direction of the sheet S are reversed and discharged from the image forming apparatus 1, the sheet S is pulled in from the reversal guidance path 52 to the switchback path 55, similar to when an image is formed on the second surface in double-sided image forming. Subsequently, the rotation direction of the reversal upper roller pair 53 and the reversal lower roller pair 54 is switched to the opposite direction from when it was pulled in, so that the front and back sides and the leading and trailing ends in the transport direction of the sheet S are swapped and it is discharged from the switchback path 55. The sheet S is then discharged from the image forming apparatus 1 by the outer discharge roller 49 via the reversal discharge path 56 and sent to the buffer path 81 of the finisher 80 in the same manner as described above.

[0027] <Finisher> As shown in Figure 1, the finisher 80 includes a buffer path unit 181 that transports the sheets S discharged from the image forming apparatus 1, and a post-processing unit (finisher body) 108 that processes the sheets S transported by the buffer path unit 181. The buffer path unit 181 has a buffer path 81 which is a sheet transport path that guides the sheets S to be transported to the post-processing unit 108. The buffer path 81 is connected downstream of the discharge transport path 51 of the image forming apparatus 1 in the direction of transport of the sheets S. The finisher 80 also has discharge loading sections 83a, 83b, 83c, and 83d to which the sheets S processed by the post-processing unit 108 are discharged. Note that the buffer path unit 181 and the post-processing unit 108 may be separate units, and the image forming apparatus 1 may be connected to the post-processing unit 108 via the buffer path unit 181.

[0028] As shown in Figure 2, an operating unit 201 is provided on the top surface of the image forming apparatus 1. The operating unit 201 functions as a display device that shows information related to the image forming apparatus 1, and also functions as an input device for inputting various settings into the image forming apparatus 1. In this specification, the side from which the user stands when operating the operating unit 201 to operate the image forming apparatus 1 is referred to as the "front," the opposite side as the "rear," the right side when viewed from the front as the "right," and the left side when viewed from the front as the "left." The upper side when viewed from the front is referred to as the "top," and the lower side when viewed from the front as the "bottom."

[0029] <Exterior cover> Next, the exterior cover, which is installed to form the exterior of the image forming apparatus 1, mainly for aesthetic purposes, will be explained using Figures 2 to 5 with reference to Figure 1. Figure 2 shows the image forming apparatus 1 with the manual feed unit 30 installed, and Figure 3 shows the image forming apparatus 1 without the manual feed unit 30 installed.

[0030] As shown in Figure 2, the top surface of the image forming apparatus 1 is fitted with, in order from the front, the main body upper front cover 221, the printer cover 222, and the rear upper cover 318, forming a highly aesthetically pleasing upper exterior surface. On the front of the image forming apparatus 1, from top to bottom, are the front upper opening / closing cover 223, the front middle cover 224, the front opening / closing cover 225, the right paper feed cover 226 and the left paper feed cover 227, and the bottom paper feed cover 228, forming a highly aesthetically pleasing front exterior surface. In particular, the front upper opening / closing cover 223, the front middle cover 224, the front opening / closing cover 225, the right paper feed cover 226 and the left paper feed cover 227, and the bottom paper feed cover 228 are arranged to form a nearly identical plane with minimal protrusions, resulting in a highly aesthetically pleasing design. Note that multiple exterior covers may also be fitted to the back of the image forming apparatus 1.

[0031] The front upper opening / closing cover 223 is provided on the housing 1A so that its upper end can be opened and closed by rotating around a left-right rotation axis (not shown) provided at its lower end, in order to replace the toner bottle (not shown) containing toner for supplying toner to the developer 64. The front middle cover 224 is located below the front upper opening / closing cover 223 and is fixed to the housing 1A. The front middle cover 224 has an opening with louvers that rectify the outside air taken into the housing 1A. The front opening / closing cover 225 is located below the front middle cover 224 and is provided on the housing 1A so that its left end can be opened and closed by rotating around a vertical rotation axis (not shown) provided at its right end, in order to maintain and replace the photoreceptor 61, charger 62, exposure unit 63, developer 64, or fuser 45, intermediate transfer belt 67, etc.

[0032] A right paper feed cover 226 is located to the lower right of the front opening / closing cover 225, and a left paper feed cover 227 is located to the lower left of the front opening / closing cover 225. The right paper feed cover 226 is provided on the paper feed cassette 31, which is installed on the right side within the housing 1A, and the left paper feed cover 227 is provided on the paper feed cassette 32, which is installed on the left side within the housing 1A. Below these right paper feed cover 226 and left paper feed cover 227, a lower paper feed cover 228 is located. The lower paper feed cover 228 is provided on the paper feed cassette 33, which is installed below the paper feed cassettes 31 and 32 within the housing 1A. Therefore, the right paper feed cover 226, left paper feed cover 227, and lower paper feed cover 228 move integrally with the paper feed cassettes 31, 32, and 33, which are slidable in the front-rear direction relative to the housing 1A to replenish the sheets S.

[0033] Multiple exterior covers are arranged on the right side of the image forming apparatus 1 to create a highly aesthetically pleasing right exterior surface. While multiple exterior covers may also be arranged on the left side of the image forming apparatus 1 to create a highly aesthetically pleasing left exterior surface, this will not be explained here.

[0034] As shown in Figure 3, a right side cover 301 is positioned in the center of the front-to-back direction on the right side of the image forming apparatus 1. The right side cover 301 is detachably attached to the housing 1A and is attached to the housing 1A by screws or the like when the manual feed unit 30 is not installed. In other words, when the manual feed unit 30 is installed, the right side cover 301 is removed from the housing 1A. In the following explanation, we will use the case where the manual feed unit 30 is not installed and the right side cover 301 is attached to the housing 1A as an example.

[0035] Above the right side cover 301, from bottom to top, are the right middle upper cover 304 and the right upper cover 305, which are installed on the housing 1A. Below the right side cover 301, from top to bottom, are the right side middle cover 307, the right opening / closing door cover 308, and the right side lower cover 309. The right side middle cover 307 is installed on the housing 1A. The right opening / closing door cover 308 is installed on the housing 1A so that its front end can be opened and closed by rotating around a vertical rotation axis (not shown) provided at its rear end, in order to remove a sheet S from the sheet transport section 109 if a jam occurs in the middle of the sheet transport section 109 when a sheet S fed from the paper feed cassette 33 gets stuck there.

[0036] Furthermore, a right-upper front cover 306 is positioned between the front upper opening / closing cover 223, the front middle cover 224, and the front opening / closing cover 225 on the front side of the right side cover 301, and the right-upper front cover 306 is provided on the housing 1A. Right-upper rear covers 302 and 303 are positioned behind the right side cover 301, and the right-upper rear covers 302 and 303 are provided on the housing 1A. In addition, a right-lower front cover 312 is positioned between the front opening / closing cover 225, the right paper feed cover 226, and the bottom paper feed cover 228 on the front side of the right opening / closing door cover 308, and the right-lower front cover 312 is provided on the housing 1A. Right-lower rear covers 310 and 311 are positioned behind the right opening / closing door cover 308, and the right-lower rear covers 310 and 311 are provided on the housing 1A.

[0037] Figure 4 shows the housing 1A side (inside) of the right side cover 301. As shown in Figure 4, multiple ribs 323 are provided extending vertically (third direction) from the inner surface of the lower end of the right side cover 301 to increase the rigidity of the lower end. It is preferable that these ribs 323 are formed at equal intervals in the front-rear direction of the right side cover 301 at the lower end of the right side cover 301, as this can further increase rigidity.

[0038] Figure 5 is a schematic diagram showing the AA cross-section of Figure 3. However, in order to make the explanation easier to understand, the sound-absorbing material 322 (see Figures 6 and 7), which will be described later, is not shown in Figure 5. As shown in Figure 5, there is a gap Q1 between the right side middle cover 307, which is the first cover member, and the right side cover 301, which is the second cover member, which are arranged adjacent to each other in the vertical direction. The gap Q1 is left to prevent the right side middle cover 307 from coming into contact with and damaging the right side cover 301 or the manual feed unit 30 when attaching or detaching them.

[0039] As described above, the sheets S fed from the paper feed cassettes 31-33 by the feed rollers 36-38 are transported through the supply transport path 41 to the register roller 42, where the register roller 42 forms a loop of sheets S. During this process, transport noise and driving noise of the register roller 42 are generated. In this embodiment, no shielding is provided between the supply transport path 41 and the register roller 42 and the right side cover 301 and the right side middle cover 307 within the housing 1A. If the transport noise and driving noise described above leak to the outside through the gap Q1 between the right side cover 301 and the right side middle cover 307, it will become an unpleasant noise for the user of the image forming apparatus 1. Therefore, in this embodiment, sound-absorbing material is provided to at least partially block the gap Q1 in order to suppress sound leakage to the outside through the gap Q1 between the right side cover 301 and the right side middle cover 307. The sound-absorbing material used in this embodiment will be explained with reference to Figures 6 and 7.

[0040] <Sound-absorbing material> The sound-absorbing material 322 is formed in a long, elongated shape in the front-to-back direction from a porous material that has sound-absorbing properties and elasticity, such as a foamed material such as ethylene propylene diene rubber (EPDM) or urethane sponge, or glass fiber glass wool or mineral rock wool. As shown in Figure 6, the sound-absorbing material 322 is attached to the mounting portion 307a formed by bending the upper end of the right side middle cover 307 by adhesive, for example, double-sided tape, so as not to protrude beyond the outer surface 307b of the right side middle cover 307. Therefore, the sound-absorbing material 322 is not exposed in a position visible to the user, and the design of the appearance of the image forming apparatus 1 formed by the right side cover 301 and the right side middle cover 307 is not impaired.

[0041] When the sound-absorbing material 322 is attached to the mounting portion 307a of the right side middle cover 307, the gap Q1 between the right side cover 301 and the right side middle cover 307 is sealed by the sound-absorbing material 322 when the right side cover 301 is installed. In this way, the gap Q1 through which sound leaked from the inside to the outside of the housing 1A is sealed by the sound-absorbing material 322, and some of the transport noise associated with the transport of the sheet S and the driving noise of the register roller 42 are absorbed, reducing the volume. Therefore, sound leakage to the outside, such as transport noise and driving noise generated inside the housing 1A, is suppressed.

[0042] To more reliably seal the gap Q1, the sound-absorbing material 322 is pressed in some areas by the rib 323 of the right side cover 301. The sound-absorbing material 322 is pressed from right to left by the rib 323, and the areas pressed by the rib 323 are compressed by a length "L1 (for example, 5 mm)". In other words, the rib 323 presses the sound-absorbing material 322 from its right end so that a length "L1 (for example, 5 mm)" from the left end of the rib 323 penetrates the sound-absorbing material 322 in the left-right direction.

[0043] Incidentally, in the past, the sound-absorbing material was pressed against the right side cover 301 by the ribs 323 of the right side cover 301, causing the right side cover 301 to flex. Here, the flexing of the right side cover 301 that occurred in the conventional case will be explained using Figures 9(a) and 9(b). Figure 9(a) shows the case when the sound-absorbing material 325 is not placed, and Figure 9(b) shows the case when the sound-absorbing material 325 is placed. The conventional sound-absorbing material 325 differs from the sound-absorbing material 322 used in this embodiment, which will be described later, in that it does not have slits formed therein.

[0044] As shown in Figure 9(a), if the sound-absorbing material 325 is not placed at all, the right side cover 301 forms a nearly identical plane with the right side middle cover 307, resulting in a highly aesthetic design with no irregularities. In contrast, as shown in Figure 9(b), the sound-absorbing material 325, which is placed to fill the gap Q1, is pressed against the rib 323 of the right side cover 301, causing the right side cover 301 to flex. This is because the right side cover 301 is pushed back by the repulsive force of the sound-absorbing material 325, which has been compressed by the rib 323. As a result, a step "L3" is created between the right side cover 301 and the right side middle cover 307, making the right side cover 301 appear to bulge outward relative to the right side middle cover 307, and impairing the aesthetic design of the appearance formed by the right side cover 301 and the right side middle cover 307. To suppress this flexing of the right side cover 301, it is possible to change the size or thickness of the sound-absorbing material 325, or to change the material of the sound-absorbing material 325. However, the former would impair the sound-absorbing material 325's function of filling gaps, and the latter would increase costs, making their adoption difficult.

[0045] In view of the above points, the sound-absorbing material 322 described below is used in this embodiment. Figure 7 is a top view showing the sound-absorbing material 322 used in this embodiment. As shown in Figure 7, unlike the conventional sound-absorbing material 325, the sound-absorbing material 322 has slits 324 formed at at least one location on the right end portion 322f that can be pressed by the rib 323 of the right side cover 301. In the embodiment shown in Figure 7, multiple slits 324 cut from the end face of the right end portion 322f are formed at multiple locations on the right end portion 322f, spaced apart in the longitudinal direction of the elongated sound-absorbing material 322 (the second direction intersecting the first direction pressed by the right side cover 301, in this case the front-to-back direction). When using sound-absorbing material 322 with multiple slits 324, the pressing force received from the rib 323 can be evenly released in the longitudinal direction by the multiple slits 324 compared to sound-absorbing material 322 with a single slit 324, thus further reducing the repulsive force of the sound-absorbing material 322.

[0046] Preferably, the multiple slits 324 are formed at the ends in a position where they are sandwiched between a rib 323 (first rib) and another rib 323 (second rib) in the longitudinal direction. In this case, when the sound-absorbing material 322 is pressed by the ribs 323, the area 322b between the slits 324 elastically deforms without affecting the adjacent area 322c (only a portion is shown in Figure 7). In other words, because the slits 324 are formed in the sound-absorbing material 322, each area (322b, 322c) divided by the slits 324 undergoes elastic deformation in response to the pressure from the multiple ribs 323. As a result, when the sound-absorbing material 322 is pressed by the ribs 323, it is difficult for a pressure difference to occur between the multiple areas (322b, 322c), and the repulsive force of the sound-absorbing material 322 that occurs in response to the pressing force from the ribs 323 can be reduced.

[0047] Furthermore, in each range 322b (322c), it is preferable that the slit 324 be formed in the center in the longitudinal direction. This is because, when the sound-absorbing material 322 is pressed by the rib 323, the pressing force received from the rib 323 can be more easily released evenly in the longitudinal direction in the above-mentioned ranges (322b, 322c).

[0048] Furthermore, each slit 324 is formed such that the slit length "L2" in the short-side direction (left-right direction) of the sound-absorbing material 322 is longer than the amount "L1" (see Figure 6) of the rib 323 of the right side cover 301 that penetrates the sound-absorbing material 322 (L2 > L1). For example, if the amount "L1" of the rib 323 penetration is "5 mm", the slit length "L2" is formed to be longer than "5 mm" (for example, 6 mm). In this way, by making the slit length "L2" longer than the amount "L1" of the rib 323 penetration, the sound-absorbing material 322 becomes more easily elastically deformed in the longitudinal direction when pressed by the rib 323, and the repulsive force of the sound-absorbing material 322 is more easily reduced, which is preferable.

[0049] Furthermore, as shown in Figure 7, the sound-absorbing material 322 of this embodiment has inclined portions 322d formed at both ends in the longitudinal direction, in accordance with the slit length "L2". The inclined portions 322d are formed such that their longitudinal length increases as they move away from the end face of the right end portion 322f in the left-right direction. The inclined portions 322d are formed so that their length from the end face in the left-right direction is approximately the same as the length of the slit 324. The formation of such inclined portions 322d is preferable because it makes it easier for the pressing force received from the rib 323 to escape in the longitudinal direction when the sound-absorbing material 322 is pressed by the rib 323.

[0050] As described above, in this embodiment, a sound-absorbing material 322 with a slit 324 is used to seal the gap Q1 between the right side cover 301 and the right side middle cover 307. The slit 324 is cut into the end face of the right end portion 322f of the sound-absorbing material 322, which is pressed by the right side cover 301 (more specifically, the rib 323). Because the slit 324 is formed in the sound-absorbing material 322, the repulsive force of the sound-absorbing material 322 that is generated in response to the pressing force received from the right side cover 301 when the sound-absorbing material 322 is pressed by the right side cover 301 can be reduced.

[0051] In particular, as shown in Figure 7, when multiple slits 324 are formed in a longitudinal direction, the area 322b sandwiched between the slits 324 undergoes elastic deformation without affecting the adjacent area 322c, thereby further reducing the repulsive force of the sound-absorbing material 322 that occurs in response to the pressing force received from the rib 323. In this way, by using sound-absorbing material 322 with slits 324 formed therein, it is possible to suppress sound leakage to the outside from the gap Q1 while suppressing the bending of the right side cover 301 caused by the repulsive force of the compressed sound-absorbing material 322.

[0052] Furthermore, in this embodiment, in addition to using sound-absorbing material 322 with slits 324 formed therein, the rigidity of the lower end of the right side cover 301 is increased by the ribs 323, so that deflection of the right side cover 301 due to the repulsive force of the compressed sound-absorbing material 322 can be further suppressed. In this case, it is sufficient to form the ribs 323 at the lower end of the right side cover 301, which is advantageous because it is expected to reduce the weight and cost of the right side cover 301 compared to increasing the overall rigidity of the right side cover 301.

[0053] [Other embodiments] In the embodiment described above, the case in which the gap Q1 between the right side cover 301 and the right side middle cover 307 is sealed with sound-absorbing material 322 has been explained, but it is not limited to this. The sound-absorbing material 322, which has the above-described slit 324 formed therein, may be applied to seal the gap between the first outer cover, which is provided to be removable or openable, and the second outer cover, which is arranged adjacent to the first outer cover, not limited to the vertical direction.

[0054] Furthermore, even when the manual feed unit 30 is mounted on the housing 1A, the sound-absorbing material 322 with the aforementioned slit 324 may be used to close the gap Q2 between the manual feed tray and the right side middle cover 307. The following explanation will be given with reference to Figure 8. Note that in Figure 8, the same reference numerals are used for components that are similar to those in the embodiments described above, and the explanation is simplified or omitted.

[0055] As shown in Figure 8, the manual feed unit 30 has a manual feed tray 30a, which is rotatable around a pivot axis 30b between a first position F1 (closed) and a second position F2 (open). When the manual feed tray 30a is in the second position F2, a sheet S is loaded onto the manual feed tray 30a. The surface of the manual feed tray 30a is provided with a manual feed cover 30a1 that, when closed, forms a nearly identical plane with the right upper center cover 304 and the right side center cover 307, resulting in a highly aesthetic design.

[0056] When the manual feed unit 30 is installed, a gap Q2 exists between the pivot axis end of the manual feed tray 30a and the right side middle cover 307. If there is a gap Q2, the transport noise associated with the transport of the sheet S and the driving noise of the registration roller 42 will leak to the outside, resulting in unpleasant noise for the user of the image forming apparatus 1. Therefore, even when the manual feed unit 30 is installed, sound-absorbing material 322 is provided to seal the gap Q2 between the manual feed tray 30a and the right side middle cover 307 in order to suppress sound leakage to the outside.

[0057] The sound-absorbing material 322 is a sound-absorbing material with the aforementioned slit 324 formed therein (see Figure 7), and it seals the gap Q2. In this embodiment, the gap Q2 is sealed by the sound-absorbing material 322 whether the manual feed tray 30a is in the first position F1 (closed) or the second position F2 (open). As a result, even when the manual feed paper unit 30 is optionally installed, sound leakage from the gap Q2 to the outside can be suppressed without changing the material or placement of the sound-absorbing material 322. In addition, when the sound-absorbing material 322 is pressed by the manual feed tray 30a, the repulsive force of the sound-absorbing material 322 that is generated in conjunction with the pressing force received from the manual feed tray 30a can be reduced. Therefore, when the manual feed tray 30a is in the closed position, the design of the appearance formed by the right upper center cover 304 and the right side center cover 307 is not impaired. Note that a rib similar to the rib 323 described above may be provided at the end of the manual feed tray 30a on the pivot axis side.

[0058] In the embodiments described above, an electrophotographic image forming apparatus that forms a toner image on a sheet using a developer containing toner was used as an example. However, the invention is not limited to this, and the sound-absorbing material with the aforementioned slits may be applied to image forming apparatuses of other types. For example, it may be applied to an inkjet image forming apparatus that forms an image by ejecting ink toward a sheet. [Explanation of symbols]

[0059] 1…Image forming apparatus, 30…Manual feed unit, 301(30a1)…Second cover member (right side cover, manual feed cover), 307…First cover member (right side middle cover), 322…Sound absorbing material, 322d…Inclined section, 322f…End section, 323…Rib (first rib, second rib), 324…Slit, Q1(Q2)…Gap, S…Recording material (sheet)

Claims

1. An image forming apparatus for forming an image on a recording material, A first cover member that forms the outer surface of the image forming apparatus, A second cover member is positioned next to the first cover member and, in combination with the first cover member, forms the exterior surface of the image forming apparatus. The device comprises a sound-absorbing material that at least partially seals the gap between the first cover member and the second cover member, The sound-absorbing material has a slit cut from the end face of the second cover member at the end of the second cover member. An image forming apparatus characterized by the following features.

2. The sound-absorbing material has a plurality of slits arranged in a second direction that intersects the first direction in which the second cover member presses at its end. The image forming apparatus according to feature 1.

3. The second cover member has ribs extending in a third direction that intersects the first direction and the second direction, at a position facing the sound-absorbing material with respect to the first direction, The ribs are formed in the second direction so as to be able to press against multiple locations on the end of the first cover member with respect to the second direction, The sound-absorbing material is such that the slits are formed at the end where they are sandwiched between the first rib and the second rib in the second direction. The image forming apparatus according to feature 2.

4. The sound-absorbing material is such that, with respect to the first direction, the length of the slit is longer than the amount of intrusion from the end face of the rib into the sound-absorbing material. The image forming apparatus according to feature 3.

5. The sound-absorbing material does not protrude outward beyond the surface of the first cover member and the surface of the second cover member with respect to the first direction. The image forming apparatus according to feature 2.

6. The sound-absorbing material has inclined portions at both ends in the second direction, the length of which increases in the second direction as it moves away from the end face with respect to the first direction. The image forming apparatus according to feature 2.

7. The inclined portion is formed such that its length from the end face in the first direction is approximately the same as the length of the slit. The image forming apparatus according to feature 6.

8. The sound-absorbing material is provided in a state of elastic deformation by being pressed against the first cover member and the second cover member. The image forming apparatus according to feature 1.

9. It is equipped with a manual feed unit that has a manual feed tray for loading recording materials, The first cover member is positioned adjacent to the manual feed tray. The second cover member is provided on the surface of the manual feed tray. The image forming apparatus according to feature 1.

10. The manual feed tray is provided on the manual feed paper unit so as to be rotatable around a pivot axis, The sound-absorbing material seals the gap between the first cover member and the end of the manual feed tray on the pivot axis side. The image forming apparatus according to feature 9.

Images