Image forming apparatus and sheet conveying apparatus

Abstract

To allow replacement of a cover with a simple method to reduce the time for replacing the cover.SOLUTION: An image forming apparatus of the present invention has: a cover that is openable and closable with respect to an apparatus body; a movable member that is provided inside the apparatus body and exposed to the outside when the cover is opened; a support member that supports the movable member and is openable and closable with respect to the apparatus body; and a support shaft that supports both the cover and the support member openably and closably with respect to an apparatus body. Along with rotation of the cover centered on the support shaft, the movable member and the support member move together with the cover. The support shaft is movable between a first position for supporting the cover and the support member and a second position for not supporting the cover but supporting the support member, and moving the support shaft to the second position allows removal of the cover from the apparatus body.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus and a sheet conveying apparatus in which a cover, which is a part of an exterior member, is easily replaced. [Background technology]

[0002] Conventionally, many image forming devices such as printers use covers molded from plastic materials as exterior members. Patent Document 1 describes an image forming device in which the front cover of a paper feed cassette is configured to be cut and separated from the sheet storage section, so that it can be replaced with a new front cover. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2003-300634 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, the image forming device described in Patent Document 1 discloses a configuration in which the front cover of the paper feed cassette can be replaced, but does not disclose a configuration in which the covers of other parts can be replaced. In addition, Patent Document 1 assumes a situation in which the image forming device is collected from the market and reused in a new product. Therefore, it is difficult to say that the configuration allows dealers to easily replace the printer in an environment where the printer has already been delivered to the user, as it involves a process of cutting off the front cover and the housing part of the paper feed cassette.

[0005] An example of a cover of an image forming apparatus that occupies a large area is the front cover located on the front side of the apparatus body. A manual feed tray into which a user can directly insert a sheet is generally provided inside this front cover. In this configuration, the manual feed tray is fixed to the front cover in order to increase the positional accuracy of the manual feed tray. As a result, in order to replace the front cover, it is first necessary to remove the manual feed tray and the front cover together from the apparatus body, and then to remove the manual feed tray from the front cover, which causes a problem that it takes time to replace the cover.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a method for replacing a cover in a simple manner and to reduce the time required for replacing the cover. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the image forming apparatus of the present invention has a cover that can be opened and closed relative to the apparatus body, a movable member that is provided inside the apparatus body and exposed to the outside when the cover is opened, a support member that supports the movable member and is openable and closable relative to the apparatus body, and a support shaft that supports the cover and the support member in a state in which both can be opened and closed relative to the apparatus body, wherein as the cover rotates around the support shaft, the movable member and the support member move together with the cover, and the support shaft is movable between a first position that supports the cover and the support member and a second position that supports the support member without supporting the cover, and the cover can be removed from the apparatus body by moving the support shaft to the second position.

[0008] In addition, in order to achieve the above-mentioned object, the sheet conveying device of the present invention has a cover that can be opened and closed relative to the device main body, a movable member that is provided inside the device main body and exposed to the outside when the cover is opened, a support member that supports the movable member and is openable and closable relative to the device main body, and a support shaft that supports the cover and the support member in a state in which both can be opened and closed relative to the device main body, wherein as the cover rotates around the support shaft, the movable member and the support member move together with the cover, and the support shaft is movable between a first position that supports the cover and the support member and a second position that supports the support member without supporting the cover, and the cover can be removed from the device main body by moving the support shaft to the second position. Effect of the Invention

[0009] According to the present invention, the cover can be replaced in a simple manner, and the time required for replacing the cover can be shortened. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view showing a configuration of an image forming apparatus. [Diagram 2] FIG. 1 is a perspective view showing a manual paper feed unit in an open and closed state according to the first embodiment; [Diagram 3] FIG. 13 is a diagram illustrating a state in which sheets are stacked on a manual sheet feed unit in the first embodiment. [Figure 4] FIG. 1 is a perspective view showing a paper feed mechanism of a manual paper feed unit according to a first embodiment; [Diagram 5] FIG. 1 is a diagram showing a support structure of a manual paper feed unit in the first embodiment; [Figure 6] FIG. 1 is an exploded perspective view of a manual paper feed unit according to a first embodiment; [Figure 7] FIG. 13 is a diagram showing the position of the support shaft when the cover is attached or detached in the first embodiment. [Figure 8] FIG. 1 is a diagram for explaining the state of removing the cover in the first embodiment. [Figure 9] 1 is a diagram showing the state before and after replacement of the cover in the first embodiment; FIG. [Figure 10] Diagram explaining the difference between having and not having an extension tray [Figure 11] FIG. 11 is a perspective view showing a state in which a transport guide unit in a second embodiment is opened and closed; [Figure 12] FIG. 11 is a diagram showing a support structure of a transport guide unit in the second embodiment; [Figure 13] FIG. 13 is a diagram showing the position of the support shaft when the conveying guide is attached or detached in the second embodiment. [Figure 14] FIG. 11 is a diagram illustrating a state in which the conveying guide is removed in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Example 1> Preferred embodiments of the present invention will be described in detail as examples. However, the dimensions, materials, shapes, and relative positions of the components described in the following embodiments may be changed as appropriate depending on the configuration of the device to which the present invention is applied and various conditions. Therefore, unless otherwise specified, it is not intended to limit the scope of the present invention to only those.

[0012] [Overall configuration of image forming device] 1 is a cross-sectional view of an image forming apparatus 100 in this embodiment. The image forming apparatus 100 in this embodiment is a monochrome laser printer using an electrophotographic method, and forms an image on a sheet S in accordance with image information transmitted from an external device such as a personal computer. Examples of the sheet S include recording paper, label paper, OHP sheets, cloth, etc.

[0013] In the following description, the height direction (opposite to the vertical direction) of the image forming apparatus 100 when the image forming apparatus 100 is installed on a horizontal surface is referred to as the Z direction. The direction that intersects with the Z direction and is parallel to the rotation axis direction (main scanning direction) of the photosensitive drum 2 described later is referred to as the Y direction. The direction that intersects with the Y direction and the Z direction is referred to as the X direction. The X direction, Y direction, and Z direction preferably intersect perpendicularly with each other. For convenience, the positive side in the X direction is referred to as the front side or front side, and the negative side is referred to as the rear side or back side, the positive side in the Y direction is referred to as the right side, and the negative side is referred to as the left side, and the positive side in the Z direction is referred to as the upper side, and the negative side is referred to as the lower side.

[0014] The image forming apparatus 100 is broadly composed of a paper feeding section that feeds the sheet S, an image forming section that forms a toner image on the sheet S, a fixing section that fixes the toner image to the sheet S, and a paper ejection section that ejects the sheet S with the image formed thereon to the outside.

[0015] The image forming unit includes a process cartridge 1 that is detachable from the apparatus main body 101. The process cartridge 1 is composed of a photosensitive drum 2 and process members such as a developing roller and a charging roller (not shown). A scanner unit 3 is disposed vertically above the process cartridge 1, and exposes the photosensitive drum 2 based on an image signal. The photosensitive drum 2 is charged to a predetermined negative potential by a charging roller (not shown), and then exposed by the scanner unit 3 to form an electrostatic latent image. The electrostatic latent image is reverse-developed by a developing roller (not shown) in the process cartridge 1, and negative toner is attached to the photosensitive drum 2, forming a toner image on the photosensitive drum 2.

[0016] The image forming apparatus 100 of this embodiment has two paper feed units. One is a cassette paper feed unit, and the other is a manual paper feed unit. The cassette paper feed unit is composed of a paper feed roller 4 provided in the apparatus body 101, and a paper feed cassette 5 that is detachable from the apparatus body 101 and stores sheets S. When the paper feed roller 4 is rotated by a driving force from a driving source (not shown), the sheets S stored in the paper feed cassette 5 are separated and fed one by one.

[0017] The manual feed section is made up of manual feed rollers 58 provided in the device body 101, and a manual feed unit 51 provided so as to be openable and closable relative to the device body 101. When using the manual feed section, the manual feed unit 51 is opened to a predetermined angle relative to the device body 101, and sheets S are loaded on the manual tray 53 and extension tray 54 in the manual feed unit 51. When the manual feed rollers 58 are rotated by a driving force from a driving source (not shown), the sheets S loaded on the manual tray 53 are separated and fed one by one.

[0018] The sheet S fed from each paper feed unit is transported to a pair of registration rollers 7, where skew correction is performed, and the sheet S is transported to a transfer unit, which is a part of the image forming unit. The transfer unit is composed of a transfer roller 8 that forms a transfer nip with the photosensitive drum 2. A positive bias is applied to the transfer roller 8 by a bias application means (not shown). As a result, the toner image formed on the photosensitive drum 2 is transferred as an unfixed image onto the sheet S transported to the transfer unit.

[0019] The sheet S onto which the toner image has been transferred is transported to a fixing device 9 (fixing section) provided downstream in the transport direction of the transfer section. The fixing device 9 fixes the toner image transferred onto the sheet S onto the sheet S, and has a heating roller 10 heated by a heater (not shown) and a pressure roller 11 which rotates while being in pressure contact with the heating roller 10. The sheet S is sandwiched and transported in the fixing nip formed by the heating roller 10 and the pressure roller 11, and the toner image is fixed onto the surface of the sheet S by applying heat and pressure.

[0020] The sheet S on which the toner image has been fixed is transported from the fixing device 9 to the paper discharge section. The paper discharge section has a triple roller set consisting of a paper discharge roller 13, a paper discharge roller 14, and a reversing roller 15, and a double-sided flapper 12. In the case of single-sided printing, the double-sided flapper 12 waits in a position (solid line position) where it guides the sheet S to the paper discharge nip formed by the paper discharge roller 13 and the paper discharge roller 14, and the sheet S is discharged onto the paper discharge tray 16 by the paper discharge roller and the paper discharge roller 14.

[0021] In the case of double-sided printing, the double-sided flapper 12 waits at a position (dotted line position) that leads the sheet S to the reversal nip formed by the discharge roller 13 and the reversal roller 15, and the sheet S is nipped by the discharge roller 13 and the reversal roller 15. The discharge roller 13 rotates in the reverse direction by a switching means (not shown) when the rear end of the sheet S reaches a predetermined position. As a result, the sheet S is conveyed to a double-sided conveying path provided with a double-sided conveying roller pair 17 and a re-feed roller pair 18 in a state in which the rear end is the leading edge and the sheet S is reversed. Thereafter, the sheet S is corrected for skew again by the registration roller pair 7 in the same manner as in single-sided printing, and an image is formed on the second side of the sheet S, after which the sheet S is discharged to the discharge tray 16 by the discharge roller 13 and the discharge roller 14, and double-sided printing is completed.

[0022] Furthermore, the transport flapper 83 operates in conjunction with the opening and closing of the transport guide cover 82, and when the transport guide unit 81 is closed, the transport flapper 83 is stored in the device body 101 and functions as a transport guide during single-sided and double-sided printing. When the transport guide unit 81 is open, the transport flapper 83 opens in conjunction with the transport guide cover 82, thereby opening the transport path for single-sided printing. This makes it easier for the user to visually confirm the transport path for single-sided printing, facilitating the disposal of jammed paper.

[0023] [Manual feed unit configuration] Next, the configuration of the manual feed unit 51 in this embodiment will be described in detail. Fig. 2 is a perspective view showing the manual feed unit 51 opened and closed relative to the apparatus main body 101. Fig. 3 is a perspective view showing the manual feed unit 51 with sheets S loaded therein. Fig. 4 is a perspective view for explaining a feed mechanism for feeding the sheets S loaded in the manual feed unit 51. Fig. 5 is a diagram showing a support configuration for the manual feed tray 53 and the extension tray 54. Fig. 6 is an exploded perspective view of the manual feed unit 51.

[0024] 2A shows a state in which manual paper feed unit 51 is not opened relative to apparatus body 101. Manual paper feed unit 51 is provided with cover 52, which constitutes a part of the exterior member of image forming apparatus 100.

[0025] 2(b) shows a state in which manual feed unit 51 is opened relative to device body 101. Manual feed unit 51 can be opened and closed relative to device body 101 in the direction of arrow A. Manual feed unit 51 is provided with a manual tray 53 (movable member) and an extension tray 54 for stacking sheets S, and a pair of support members 55 (55a, 55b) for supporting these are provided at both ends in the width direction (Y direction) of sheets S. In addition, a pair of hinge members 57 (57a, 57b) are provided for fixing manual feed unit 51 at a predetermined angle when manual feed unit 51 is opened or closed.

[0026] Regarding the support member 55 and the hinge member 57, the members located on the left side of the device are indicated with the letter a, and the members located on the right side are indicated with the letter b. The same is true for the other members below. Also, when there is no need to distinguish between the members located on the left side and the members located on the right side, they will be indicated without the letters a and b.

[0027] Fig. 3 shows a perspective view of manual feed unit 51 when viewed from a different direction than that shown in Fig. 2(b). When manual feed unit 51 is opened relative to device body 101, manual feed tray 53 is exposed to the outside, allowing the user to load sheets S on it. Also, while extension tray 54 was stored in the space between manual feed tray 53 and cover 52 in Fig. 2(b), extension tray 54 is pulled out in the direction of arrow B along the surface of cover 52 and forms a loading surface for sheets S together with manual feed tray 53.

[0028] Moreover, the cover 52 and the support member 55 are supported by a support shaft 56 relative to the device body 101. Therefore, both the cover 52 and the support member 55 are rotatable relative to the device body 101 about the support shaft 56. A part of the device body 101 that supports the cover 52 and the support member 55 is referred to as a body support part 151.

[0029] Furthermore, as will be described in detail later, cover 52 is provided with cap portion 79 (79a, 79b), and a portion of support member 55 fits inside cap portion 79. In other words, support member 55 and cover 52 are engaged with each other, so that when cover 52 is opened, support member 55 moves following cover 52. Manual tray 53 and extension tray 54 are supported by support member 55, so manual tray 53 and extension tray 54 also move following cover 52.

[0030] 4 shows a perspective view of a paper feed mechanism for feeding sheets S stacked in manual paper feed unit 51. The paper feed mechanism includes a manual paper feed roller 58 provided in device body 101, a paper feed cam 59 (59a, 59b) attached coaxially to manual paper feed roller 58, and a cam abutment portion 63 (63a, 63b) provided on manual tray 53. The paper feed mechanism further includes bosses 61 (61a, 61b) provided in device body 101 and paper feed springs 60 (60a, 60b) attached to hooks 62 (62a, 62b; 62b is not shown) provided on manual tray 53.

[0031] The manual feed tray 53 is constantly biased by a feed spring 60 in a direction in which it abuts against the manual feed roller 58, and a cam abutment portion 63 provided on the manual feed tray 53 abuts against a feed cam 59 attached coaxially with the manual feed roller 58. As the feed cam 59 rotates together with the manual feed roller 58, the manual feed tray 53 repeatedly abuts against and separates from the manual feed roller 58, and the sheets S stacked on the manual feed tray 53 are fed.

[0032] The relationship between the support member 55, the manual feed tray 53, and the extension tray 54 will be described with reference to Fig. 5. Fig. 5(a) is a diagram of the manual feed unit 51 as seen from the rear side. The manual feed tray 53 and the extension tray 54 are supported by a pair of support members 55 arranged at both ends of the sheet S in the width direction (Y direction).

[0033] Fig. 5(b) shows a cross-sectional view taken along line AA in Fig. 5(a). Note that Fig. 5(b) shows a cross-sectional view of only support member 55b, but support member 55a on the opposite side has a similar configuration. As shown in Fig. 5(b), a boss 71 is provided at the end in the width direction of manual feed tray 53, and this boss 71 is inserted into a hole 73 provided in support member 55. In this way, manual feed tray 53 is supported by support member 55 so as to be rotatable.

[0034] In addition, two bosses 72 are provided on both sides of the extension tray 54 in the width direction, and these bosses 72 are inserted into rails 74 provided on the support member 55. When the manual feed function is not used, the extension tray 54 is disposed in the space formed by the pair of support members 55, the cover 52, and the manual feed tray 53. When the manual feed function is used, the extension tray 54 can be pulled out along the rails 74 provided on the support member 55 to the upstream side in the feeding direction of the sheets S, thereby expanding the area in which the sheets S are stacked.

[0035] Fig. 6 is an exploded perspective view of manual feed unit 51. As described with reference to Fig. 5, boss 71 provided on manual feed tray 53 is inserted into hole 73 formed in support member 55, and further engages with hinge member 57. With this configuration, hinge member 57 can stably support manual feed tray 53 and support member 55.

[0036] [How to replace the cover] Next, a method for replacing cover 52 provided on manual feed unit 51 will be described. In the configuration of this embodiment, cover 52 can be replaced in a simple manner. Fig. 7 is a diagram showing a method for releasing the fixed state of cover 52 from apparatus body 101. Fig. 8 is a diagram showing a method for removing cover 52 from support member 55. Fig. 9 is a diagram showing the state when cover 52 is replaced.

[0037] 7 shows an enlarged view of the configuration in which the cover 52 and the support member 55 are supported relative to the device body 101 (body support part 151) by the support shaft 56. Although only one of the two support parts is shown in FIG. 7, the fixed state of the cover 52 relative to the device body 101 can be released in the same manner at the other support part.

[0038] In this embodiment, the support shaft 56a can take two positions. One is a fixed position (first position) where the cover 52 is fixed to the device body 101, and the other is a removal position (second position) where the cover 52 is released from the device body 101. Fig. 7(a) shows the support shaft 56a in the fixed position, and Fig. 7(b) shows the support shaft 56a in the removal position.

[0039] 7(a), the support shaft 56a is inserted into holes provided in a total of three places: a bearing portion 155 which is a part of the support member 55a, a body support portion 151 which is a part of the device body 101, and a cover bearing portion 152 which is a part of the cover 52. As a result, the cover 52 and the support member 55a are supported in a state in which they can be opened and closed relative to the device body 101 around the support shaft 56.

[0040] During normal use, such as when printing with the image forming apparatus 100, the support shaft 56a is located at a fixed position. On the other hand, when replacing the cover 52, the dealer moves the support shaft 56a in the direction of arrow C to the removal position. In FIG. 7(b), the support shaft 56a is removed from the cover bearing portion 152, so that the cover 52 is free from the apparatus body 101.

[0041] 7(b), in the removal position, the support shaft 56a is removed from the cover bearing portion 152, but remains inserted into the bearing portion 155 and the main body support portion 151. This prevents not only the cover 52 but also members other than the cover 52 (the support member 55a, the manual feed tray 53 supported by the support member 55a, and the extension tray 54) from being removed from the device main body 101, which makes the work of replacing the cover 52 complicated.

[0042] Further, the support member 55a is provided with a guide portion 70 for guiding the movement of the support shaft 56a, and the guide portion 70 is further provided with a groove portion 75 and a groove portion 76. The support shaft 56a is provided with a protrusion portion 78. In the fixed position shown in FIG. 7(a), the protrusion portion 78 of the support shaft 56a is located in the groove portion 75 of the support member 55a, and in the detached position shown in FIG. 7(b), the protrusion portion 78 of the support shaft 56a is located in the groove portion 76 of the support member 55a. The protrusion portion 78 fits into the groove portion 75 or the groove portion 76, so that the position of the support shaft 56a is stabilized in the state shown in FIG. 7(a) and FIG. 7(b). With this configuration, when the dealer moves the support shaft 56a from the fixed position to the detached position in order to replace the cover 52, the support shaft 56a can be stopped at a predetermined position without coming off the device main body 101. The guide portion 70 does not have to be provided on the support member 55a, and may be provided on the main body support portion 151, for example.

[0043] 8 shows how cover 52 is removed from device body 101. After moving support shaft 56 and removing it from cover bearing portion 152, the dealer slides cover 52 in the direction of arrow D (vertically upward). This allows cap portion 79 provided on cover 52 to be removed from protrusion 80, which is part of support member 55. This method makes it possible to remove cover 52 alone from device body 101 and support member 55 without removing manual paper feed unit 51 from device body 101.

[0044] 9 shows the state in which the cover 52 originally installed on the device body 101 has been replaced with a new cover 252. The configuration of this embodiment allows the cover 52 to be replaced in a simple manner, so that a dealer or the like can easily replace the cover with a new cover 252 in an environment in which the printer has already been delivered to the user.

[0045] By adopting the configuration of the first embodiment, when replacing cover 52 of manual feed unit 51, cover 52 can be replaced alone while manual feed tray 53 and extension tray 54 remain in device main body 101. Moreover, the time required to replace cover 52 can be shortened compared to the conventional method.

[0046] In the configuration of this embodiment, a pair of support members 55 supports both sides in the width direction of manual feed tray 53 and extension tray 54. This allows extension tray 54 to be stored between manual feed tray 53 and cover 52, making it possible to reduce the size of the main body.

[0047] In the above embodiment, the description is given on the assumption that the extension tray 54 is provided in addition to the manual feed tray 53, but the present invention is not limited to this. The manual feed unit 51 does not have to include the extension tray 54.

[0048] 10 is a diagram showing the difference in thickness of manual paper feed unit 51 when extension tray 54 is present (FIG. 10(a)) and when it is not (FIG. 10(b)). When extension tray 54 is not provided, cover 52 can be positioned further inside the device than when extension tray 54 is present, making it possible to reduce the size of the main body by the amount of thickness La.

[0049] <Example 2> In the first embodiment, the configuration for replacing the cover 52 of the manual feed unit 51 is described, but in the present embodiment, the configuration for replacing the transport guide cover 82 of the transport guide unit 81 is described. Other than the characteristic configuration of this embodiment described below, the configuration is the same as that of the first embodiment, and therefore the description will be omitted.

[0050] The configuration of the transport guide unit 81 in this embodiment will be described in detail. Fig. 11 is a perspective view showing a state in which the transport guide unit 81 is opened and closed relative to the apparatus main body 101. Fig. 12 is a perspective view for explaining the mounting configuration of the transport guide unit 81 relative to the apparatus main body 101.

[0051] 11A shows a state in which the transport guide unit 81 is not opened relative to the apparatus main body 101. The transport guide unit 81 is provided with a transport guide cover 82, which constitutes a part of the exterior member of the image forming apparatus 100.

[0052] Fig. 11(b) shows a state in which the transport guide unit 81 is opened relative to the apparatus body 101. The transport guide unit 81 can be opened and closed relative to the apparatus body 101 in the direction of arrow E. The transport guide cover 82 constitutes a part of the exterior member of the image forming apparatus 100, and as shown in Fig. 11(b), has a guide surface that guides the transport of the sheet S inside the apparatus. In addition, the transport guide unit 81 is provided with a transport flapper 83 (movable member) that guides the transport of the sheet S.

[0053] When the transport guide unit 81 is closed, the transport flapper 83 has the function of guiding the sheet S during single-sided and double-sided printing. When the transport guide unit 81 is open, the transport flapper 83 opens in conjunction with the transport guide cover 82, thereby opening the transport path for single-sided printing, making it easier for the user to see the transport path and enabling removal of jammed paper.

[0054] Figure 12 shows a perspective view of the transport guide unit 81 when viewed from a different direction than that shown in Figure 11(b). The transport guide unit 81 is provided with a pair of support members 85 (85a, 85b; 85b is not shown) that support both ends in the width direction of the transport flapper 83. The transport guide cover 82 and the support members 85 are both axially supported on the apparatus main body 101 by support shafts 86 (86a, 86b; 86b is not shown).

[0055] 12, the support shaft 86a is inserted into holes provided in a total of three places: a bearing portion 185 which is a part of the support member 85, a body support portion 181 which is a part of the device body 101, and a guide bearing portion 182 which is a part of the conveyor guide cover 82. As a result, the conveyor guide cover 82 and the support member 85 are supported in a state in which they can be opened and closed relative to the device body 101, centered around the support shaft 86.

[0056] Next, a method for replacing the transport guide cover 82 provided on the transport guide unit 81 will be described. In the configuration of this embodiment, the transport guide cover 82 can be replaced in a simple manner. Fig. 13 is a diagram showing a method for releasing the fixed state of the transport guide cover 82 from the apparatus main body 101. Fig. 14 is a diagram showing a method for removing the transport guide cover 82 from the support member 85.

[0057] 13 shows an enlarged view of the transport guide cover 82 and the support member 85 supported by the support shaft 86a relative to the device body 101 (body support portion 181). Although only one of the two support portions is shown in FIG. 13, the fixed state of the transport guide cover 82 relative to the device body 101 can be released in the same manner at the other support portion.

[0058] In this embodiment, the support shaft 86a can take two positions, similar to the first embodiment. One is a fixed position (first position) in which the transport guide cover 82 is fixed to the apparatus body 101, and the other is a removal position (second position) in which the fixed state of the transport guide cover 82 is released from the apparatus body 101. Fig. 13(a) shows the support shaft 86a in the fixed position, and Fig. 13(b) shows the support shaft 86a in the removal position.

[0059] During normal use, such as when printing with the image forming apparatus 100, the support shaft 86a is located at a fixed position. On the other hand, when replacing the transport guide cover 82, the dealer moves the support shaft 86a in the direction of the arrow F to the removal position. In FIG. 13(b), since the support shaft 86a has come out of the guide shaft bearing portion 182, the transport guide cover 82 is free relative to the apparatus body 101.

[0060] 13(b), in the removal position, the support shaft 86a is removed from the guide shaft bearing portion 182, but remains inserted into the bearing portion 185 and the main body support portion 181. This prevents not only the transport guide cover 82 but also members other than the transport guide cover 82 (the support member 85a and the transport flapper 83 supported by the support member 85a) from being removed from the device main body 101, which makes the work of replacing the transport guide cover 82 complicated.

[0061] Further, the support member 85a is provided with a guide portion 90 for guiding the movement of the support shaft 86a, and the guide portion 90 is further provided with a groove portion 75 and a groove portion 76. The support shaft 86a is provided with a protrusion portion 98. In the fixed position shown in FIG. 13(a), the protrusion portion 98 of the support shaft 86a is located in the groove portion 95 of the support member 85a, and in the detached position shown in FIG. 13(b), the protrusion portion 98 of the support shaft 86a is located in the groove portion 96 of the support member 85a. The protrusion portion 98 fits into the groove portion 95 or the groove portion 96, so that the position of the support shaft 86a is stable in the state shown in FIG. 13(a) and FIG. 13(b). With this configuration, when a dealer moves the support shaft 86a from the fixed position to the detached position in order to replace the conveyor guide cover 82, the support shaft 86a can be stopped at a predetermined position without coming off the device main body 101. The guide portion 90 does not have to be provided on the support member 85a, and may be provided on the main body support portion 181, for example.

[0062] 14 shows how the transport guide cover 82 is removed from the device body 101. After the support shaft 86 is moved and removed from the guide shaft bearing portion 182, the dealer slides the transport guide cover 82 in the direction of arrow G (vertically upward). This makes it possible to remove the cap portion 89 (shown in FIG. 13) provided on the transport guide cover 82 from the protrusion (not shown) that is part of the support member 85. With this method, it becomes possible to remove the transport guide cover 82 by itself from the device body 101 and the support member 85 without removing the transport guide unit 81 from the device body 101.

[0063] The configuration of this embodiment makes it possible to replace the conveying guide cover 82 in a simple manner, so that even if the guide surface of the conveying guide cover 82 for the sheet S becomes worn due to repeated conveying of the sheet S, for example, it can be dealt with immediately.

[0064] By adopting the configuration of the second embodiment, when replacing the transport guide cover 82 of the transport guide unit 81, it is possible to replace the transport guide cover 82 alone while leaving the transport flapper 83 in the apparatus main body 101. Moreover, the time required to replace the transport guide cover 82 can be shortened compared to the conventional method.

[0065] In the configuration of this embodiment, the pair of support members 85 support both sides in the width direction of the transport flapper 83. This reduces the size of the transport guide unit 81 in the thickness direction, making it possible to reduce the size of the main body.

[0066] In the above first and second embodiments, the image forming apparatus 100 is described as a monochrome laser beam printer, but the present invention is not limited to this. The present invention may be applied to other types of image forming apparatuses, such as color laser beam printers, copiers, and facsimiles.

[0067] In the above first and second embodiments, the image forming apparatus 100 that forms an image on the sheet S has been described as an example, but the present invention is not limited to this. The present invention may be applied to a sheet conveying device that is simply equipped with a function of conveying the sheet S, such as an optional paper feed device or an optional paper discharge device that is attached to the image forming apparatus 100. [Explanation of symbols]

[0068] 52 Cover 53 Manual feed tray 55 Support member 56 Support shaft 101 Device body

Claims

1. a cover that can be opened and closed relative to the device body; a movable member provided inside the device body and exposed to the outside when the cover is opened; a support member that supports the movable member and is openable and closable with respect to the device body; a support shaft that supports the cover and the support member in a state in which both of them can be opened and closed relative to the device body, As the cover rotates about the support shaft, the movable member and the support member move together with the cover, An image forming apparatus characterized in that the support shaft is movable between a first position that supports the cover and the support member and a second position that supports the support member without supporting the cover, and the cover can be removed from the device main body by moving the support shaft to the second position.

2. 2. The image forming apparatus according to claim 1, wherein the support member is composed of a first support member and a second support member, the first support member supporting a first end of the movable member in the direction in which the support shaft extends, and the second support member supporting a second end of the movable member.

3. 3. The image forming apparatus according to claim 2, wherein the first end and the second end of the movable member are provided with bosses, and the movable member is supported by the support members by inserting the bosses into holes provided in the first support member and the second support member, respectively.

4. 4. The image forming apparatus according to claim 1, wherein the support shaft has a convex portion, and a guide portion that guides the movement of the support shaft is provided with a first groove and a second groove that engage with the convex portion, the first groove being provided at a position corresponding to the first position, and the second groove being provided at a position corresponding to the second position.

5. An image forming apparatus as described in any one of claims 1 to 4, characterized in that the cover and the support member are engaged at a position different from that of the support shaft, and when the support shaft is in the second position, the engagement between the cover and the support member is released by sliding the cover, and the cover can be removed from the device main body.

6. 6. The image forming apparatus according to claim 5, wherein the direction in which the cover is slid to release the engagement between the cover and the support member is along a surface of the support member and vertically upward.

7. 7. The image forming apparatus according to claim 1, wherein the movable member is a first tray on which sheets are stacked.

8. 8. The image forming apparatus according to claim 7, further comprising a second tray housed between the first tray and the cover, the second tray being pulled out to form a sheet loading surface together with the first tray.

9. 7. The image forming apparatus according to claim 1, wherein the movable member is a flapper that guides the conveyance of a sheet.

10. 10. The image forming apparatus according to claim 9, wherein the cover is a transport guide cover having a guide surface for guiding transport of the sheet.

11. a cover that can be opened and closed relative to the device body; a movable member provided inside the device body and exposed to the outside when the cover is opened; a support member that supports the movable member and is openable and closable with respect to the device body; a support shaft that supports the cover and the support member in a state in which both of them can be opened and closed relative to the device body, As the cover rotates about the support shaft, the movable member and the support member move together with the cover, A sheet conveying device characterized in that the support shaft is movable between a first position that supports the cover and the support member and a second position that supports the support member without supporting the cover, and the cover can be removed from the device main body by moving the support shaft to the second position.

Images