Image forming device

Abstract

To solve the problem that, when a first cover unit and a second cover unit are provided to an image forming device body so as to be openable / closable, the positional relationship of the two cover units changes due to aging, etc., rendering these to be difficult to open or close.SOLUTION: The present invention comprises an image forming device 1 body, a top cover 102 that covers the top face of the device body so as to openable / closable, and a front cover 103 that covers a front face crossing the top face, and the top cover 102 includes a pivot top frame 35 and a top panel 36 which is movably supported to the pivot top frame 35 and covers the top face. When the top cover 102 stays at a closed position and the front cover 103 is closed, the top panel 36 is moved to the pivot top frame 35 by the front cover 103 which is in the process of being closed.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus having a plurality of openable and closable covers. [Background technology]

[0002] 2. Description of the Related Art Conventionally, an image forming apparatus in which a first cover unit and a second cover unit are provided so as to be openable and closable relative to an apparatus body has been known (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-118873 A (Page 7, Figure 4) Summary of the Invention [Problem to be solved by the invention]

[0004] In these image forming devices, there was a problem in that the relative positional relationship between the two cover units changed due to manufacturing errors or misalignments over time, making it difficult to properly close one cover unit when the other cover unit was closed. [Means for solving the problem]

[0005] The image forming apparatus according to the present invention includes an apparatus main body, a first cover unit that covers a first surface of the apparatus main body in an openable and closable manner, and a second cover unit that covers a second surface intersecting with the first surface in an openable and closable manner, the first cover unit has a first base and a first cover member movably supported on the first base and covering the first surface; When the first cover unit is in a closed position and the second cover unit is closed, the first cover member is moved relative to the first base by the second cover unit in the process of being closed. Effect of the Invention

[0006] According to the present invention, the relative positional relationship between the first cover unit and the second cover unit can be kept constant regardless of manufacturing errors or deviations over time, and their opening and closing operations can always be maintained in good condition. [Brief description of the drawings]

[0007] [Figure 1] 1 is a configuration diagram showing an internal configuration of an image forming apparatus according to a first embodiment of the present invention. [Diagram 2] 1 is an external perspective view showing a state in which a top cover and a front cover of an image forming apparatus are both in a closed position. [Diagram 3] 1 is an external perspective view showing a state in which a top cover and a front cover of an image forming apparatus are both in an open position. [Figure 4] FIG. 1 is a diagram showing the essential components of an image forming apparatus according to the present invention, in which (a) is a view of the image forming apparatus in a closed position with both the top cover and the front cover closed, as viewed from the positive side in the Y direction; (b) is a bottom view of the image forming apparatus as viewed from the negative side in the Z direction; and (c) is a partially enlarged view of the tip of the front panel. [Diagram 5] 2. (a) is a partially enlarged view of the dotted line area P in FIG. 2, with some of the components removed in order to clearly show the internal configuration, and (b) is a partially enlarged view of the dotted line area P in FIG. 2, with even more components removed than in (a) in order to clearly show the internal configuration. [Figure 6] 3. (a) is a partial enlarged view of the tip of the top cover shown in Fig. 3, for example, as viewed from diagonally below, and (b) is a partial enlarged view of the tip of the front cover shown in Fig. 3, as viewed from the same direction. However, in (a), the toner cartridge and the like are removed so that the internal configuration can be seen. [Figure 7](a) shows the state when the top cover is in the open position and the front cover is in the closed position, (b) and (c) show the positional relationship between the positioning abutment member and the positioning control member when the top cover is closing, and (d) shows the positional relationship between the positioning abutment member and the positioning control member when the top cover reaches the closed position. [Figure 8] (a) shows the state when the front cover is in the open position and the top cover is in the closed position, (b) and (c) show the positional relationship between the positioning abutment member and the positioning regulating member when the front cover is closing, and (d) shows the positional relationship between the positioning abutment member and the positioning regulating member when the front cover reaches the closed position. [Figure 9] FIG. 2 is a diagram showing the configuration of a main part of a first modified example of the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Embodiment 1 1 is a diagram showing the internal configuration of an image forming apparatus 1 according to the present invention. The image forming apparatus 1 is a printer that forms color images using electrophotography.

[0009] As shown in FIG. 1, the image forming apparatus 1 includes a medium supply section 110 that supplies recording paper 4 as a recording medium, an image forming section 100 that forms a toner image (developer image), a transfer unit 120 that transfers the toner image formed in the image forming section 100 to the recording paper 4, a fixing device 130 that fixes the toner image to the recording paper 4, and a medium discharge section 140 that discharges the recording paper 4.

[0010] The medium supply section 110 has a pickup roller 112 arranged to abut against the recording paper 4 stored in the paper feed tray 111, a feed roller 113 arranged adjacent to the pickup roller 112, and a retard roller 114 arranged opposite the feed roller 113.

[0011] A paper feed tray 111, which stores recording paper 4 in a stacked state, brings the top of the stored recording paper 4 into contact with a pickup roller 112 by a lifter 115, and the pickup roller 112 rotates in contact with the recording paper 4 in the paper feed tray 111, and pays out the recording paper 4 from the paper feed tray 111. A feed roller 113 sends out the recording paper 4 paid out by the pickup roller 112 to a conveyance path. A retard roller 114 generates torque in the counter-rotation direction by a torque generating means (not shown), and applies conveyance resistance to the recording paper 4 to prevent double feeding.

[0012] In the conveying path downstream of the medium supply unit 110 in the conveying direction of the recording paper 4, a registration roller 116 and a conveying roller 118 are arranged in this order. The registration roller 116 is paired with a pressure roller 117 that rotates with the registration roller 116 to pressurize the registration roller 116 and generate a conveying force, and the conveying roller 118 is paired with a pressure roller 119 that rotates with the conveying roller 118 to pressurize the conveying roller 118 and generate a conveying force. The roller pair of the registration roller 116 corrects skew of the recording paper 4, and the roller pair of the conveying roller 118 feeds the recording paper 4 into the image forming unit 100.

[0013] The image forming section 100 has a process unit 10K that forms a black (K) toner image, a process unit 10C that forms a cyan (C) toner image, a process unit 10M that forms a magenta (M) toner image, and a process unit 10Y that forms a yellow (Y) toner image. Print heads 13K, 13C, 13M, and 13Y as exposure devices are disposed to face the photoconductor drums 11 (described later) of the process units 10K, 10C, 10M, and 10Y, respectively.

[0014] The process units 10K, 10C, 10M, and 10Y are arranged in this order along the transport direction (from right to left in the figure) of the recording paper 4. The process units 10K, 10C, 10M, and 10Y will be referred to as "process units 10" unless there is a need to distinguish them. Additionally, the print heads 13K, 13C, 13M, and 13Y will be referred to as "print head 13" unless there is a need to distinguish them.

[0015] The process unit 10 has a photoconductor drum 11 as an image carrier that carries a toner image, a charging roller 12 as a charging member, a developing roller 14 as a developer carrier, a supply roller 15 as a supply member, and a developing blade (not shown). The photoconductor drum 11 is a cylindrical member having a photosensitive layer (charge generating layer and charge transport layer) provided on the surface of a conductive base, and is rotated clockwise in the figure by a driving means (not shown).

[0016] The charging roller 12 is disposed so as to contact the surface of the photoreceptor drum 11 and rotates following the rotation of the photoreceptor drum 11. A charging voltage is applied to the charging roller 12 from a charging voltage power source (not shown), uniformly charging the surface of the photoreceptor drum 11. An electrostatic latent image is formed on the uniformly charged surface of the photoreceptor drum 11 by light irradiation from the print head 13.

[0017] The developing roller 14 is disposed so as to contact the surface of the photosensitive drum 11, and rotates in the opposite direction (counterclockwise in the figure) to the photosensitive drum 11. A developing voltage is applied to the developing roller 14 from a developing voltage power supply (not shown), and the developing roller 14 adheres to the electrostatic latent image formed on the surface of the photosensitive drum 11, forming a toner image.

[0018] Supply roller 15 is disposed so as to contact or face the surface of developing roller 14, rotates in the same direction as developing roller 14, is applied with a supply voltage by a supply voltage power source (not shown), and supplies toner to developing roller 14. The developing blade (not shown) is a metal blade that is long in the axial direction of developing roller 14, is disposed so as to be pressed against the surface of developing roller 14, and regulates the thickness of the toner layer formed on the surface of developing roller 14.

[0019] Above the process units 10K, 10C, 10M, and 10Y, toner cartridges 20K, 20C, 20M, and 20Y (see FIG. 3) are provided as developer containers that supply toner of each color to the process units 10K, 10C, 10M, and 10Y. The toner cartridges 20K, 20C, 20M, and 20Y are detachably attached to a top cover 102, which will be described later, and supply toner of each color to the corresponding process unit 10 via a duct 22 disposed below. Note that, unless there is a need to distinguish between them, they will be referred to as "toner cartridges 20."

[0020] The print head 13 has, for example, a light-emitting element array in which light-emitting elements such as LEDs (light-emitting diodes) are arranged, and a lens array that focuses the light emitted from the light-emitting elements on the surface of the photoconductor drum 11. The print head 13 is driven by a head control unit (not shown), and exposes the surface of the photoconductor drum 11 to light to form an electrostatic latent image.

[0021] The transfer unit 120 has an endless transfer belt 122 as a transfer body, a drive roller 123 and an idle roller 124 around which the transfer belt 122 is stretched, and four transfer rollers 121 arranged opposite the photosensitive drums 11 of each of the process units 10K, 10C, 10M, and 10Y via the transfer belt 122.

[0022] The transfer belt 122 runs while attracting and holding the recording paper 4 on its surface by electrostatic force. A drive roller 123 is rotated by a belt motor (not shown) to run the transfer belt 122, and an idle roller 124 applies tension to the transfer belt 122. A transfer voltage is applied to the transfer roller 121 by a transfer voltage power supply (not shown), and the toner image on each photoconductor drum 11 is transferred to the recording paper 4.

[0023] The fixing device 130 is disposed downstream of the image forming section 100 in the conveying direction of the recording paper 4. The fixing device 130 has, for example, a fixing belt 131 and a pressure roller 132 pressed against the fixing belt 131. The fixing belt 131 has a built-in heater (not shown) as a heat source, and the pressure roller 132 is rotated by a fixing motor (not shown). The fixing belt 131 and the pressure roller 132 apply heat and pressure to the toner image transferred to the recording paper 4, thereby fixing the toner image to the recording paper 4.

[0024] The medium discharge section 140 is disposed downstream of the fixing device 130 in the transport direction of the recording paper 4, and includes two pairs of discharge rollers 141, 142. The discharge roller pairs 141, 142 transport the recording paper 4 sent out from the fixing device 130 along a discharge transport path, and discharge the recording paper 4 to the outside of the image forming apparatus 1. A stacker section 143 for stacking the discharged recording paper 4 is provided at the top of the image forming apparatus 1.

[0025] In addition to the above configuration, the image forming apparatus 1 is also provided with a re-transport mechanism for double-sided printing, an external paper loading mechanism for loading recording media from the outside in addition to the recording paper stored in the paper feed tray 111, and the like; however, as these mechanisms are not directly related to the present invention, a description of these mechanisms will be omitted.

[0026] The image forming apparatus 1 also has an openable top cover 102 attached to the top of the main body of the image forming apparatus 1, and an openable front cover 103 attached to the front. The top cover 102 is provided with an operation panel 28 (FIG. 2) equipped with a display unit and the like. The above-mentioned toner cartridges 20K, 20C, 20M, and 20Y are also attached to the top cover 102.

[0027] In FIG. 1, the direction of the rotation axis of the photosensitive drum 11 is the Y direction. The Y direction is the width direction of the recording paper 4. The axial direction of each roller of each process unit 10 described above is parallel to the Y direction. The depth direction of the image forming apparatus 1 (left and right direction in FIG. 1), which is perpendicular to the Y direction, is the X direction. The XY plane is a horizontal plane here. The direction perpendicular to the XY plane, which is the vertical direction here, is the Z direction. With respect to the X direction, the front cover 103 side is the -X direction, and the opposite side is the +X direction.

[0028] In addition, when the X, Y, and Z directions are shown in other figures described later, these directions indicate common directions. That is, the XYZ directions in each figure indicate the arrangement directions when the depicted parts in each figure constitute the image forming apparatus 1 shown in FIG.

[0029] The top cover 102 is configured to be rotatable between a closed position and an open position, which will be described later, around a pivot shaft 25 that is positioned near the pair of discharge rollers 142 and extends in the Y direction as the center of rotation, and the front cover 103 is configured to be rotatable between a closed position and an open position, which will be described later, around a pivot shaft 26 that is positioned below the front cover 103 and extends in the Y direction as the center of rotation.

[0030] Here, the process units 10K, 10C, 10M, and 10Y are arranged in a direction inclined with respect to the X direction as shown in Fig. 1. Hereinafter, the arrangement direction of the process units 10K, 10C, 10M, and 10Y will be referred to as the unit arrangement direction (approximately the X direction). Note that the unit arrangement direction does not necessarily need to be inclined with respect to the X direction, and may be parallel to the X direction.

[0031] Fig. 2 is an external perspective view showing a state in which the top cover 102 and the front cover 103 of the image forming apparatus 1 are in a closed position, and Fig. 3 is an external perspective view showing a state in which the top cover 102 and the front cover 103 of the image forming apparatus 1 are in an open position. Note that when viewed from the direction of the arrow A (=X direction), the top (positive direction of the Z axis), bottom, left, right, front, and rear may be specified.

[0032] As shown in Figures 2 and 3, top cover 102 as a first cover unit is held by the image forming apparatus 1 main body so as to be freely rotatable around pivot axis 25 (Figure 1) which is disposed at the upper rear part of the main body of the image forming apparatus 1 and serves as a first pivot axis extending in the Y direction between a closed position (Figure 2) in which the top surface of the image forming apparatus 1 is closed and an open position (Figure 3) in which the top surface of the image forming apparatus 1 is open.

[0033] Moreover, front cover 103 as a second cover unit is held by the main body of image forming apparatus 1 so as to be rotatable around rotation shaft 26 (FIG. 1) which is disposed at the front lower part of the main body and serves as a second rotation shaft extending in the Y direction between a closed position (FIG. 2) where the front surface of image forming apparatus 1 is closed and an open position (FIG. 3) where the front surface is open. As described above, for example, for each of rotatable or detachable components such as top cover 102 of image forming apparatus 1, a portion excluding the component may be referred to as the main body of the image forming apparatus.

[0034] An operation panel 28 with a display unit is located at the upper front part of the top cover 102, and a front release lever 30 is provided at the upper right part of the front cover 103 for releasing the lock of the front cover 103 in the closed position, as described below.

[0035] 3 shows the top cover 102 in the open position, in which the four toner cartridges 20 for the four colors, the duct 22, and the four process units 10 for the four colors shown in FIG. 1 are also configured to be rotatable integrally with the top cover 102. This allows the transfer belt 122 of the transfer unit 120 (FIG. 1) to be directly visible inside the device. A top release lever 31 is provided in the center of the front side of the top cover 102 for releasing the lock of the top cover 102 when it is in the closed position.

[0036] 4 is a diagram showing the essential configuration of the image forming apparatus 1 according to the present invention, in which (a) is a diagram showing the image forming apparatus 1 in a closed position where the top cover 102 and the front cover 103 are both closed, as viewed from the positive side in the Y direction, (b) is a bottom view as viewed from the negative side in the Z direction, and (c) is a partial enlarged view of the tip of the front panel 42. However, (b) shows only the top cover 102.

[0037] As shown in FIG. 4(a), the top cover 102 includes a rotating top frame 35 as a first base that is held rotatably around a pivot axis 25 by a housing 60 that constitutes the main body of the image forming apparatus 1, and a top panel 36 as a first cover member that is slidably held by this rotating top frame 35.

[0038] As shown in Fig. 1B, the rotating top frame 35 has two pairs of long guide holes 35a, 35b, 35c, and 35d formed at positions that are centered in the Y direction. Each of the long guide holes 35a, 35b, 35c, and 35d is a long hole that extends in the X direction when the top cover 102 is closed, and engagement protrusions 36a, 36b, 36c, and 36d that are formed to face each long guide hole and hang down from the top panel 36 are fitted into each of the long guide holes. As a result, the top panel 36 is held by the rotating top frame 35 so as to be slidable.

[0039] The engagement protrusion 36a penetrates slightly beyond the long guide hole 35a, and a stop pin 37 having a disk-shaped head with a diameter larger than the width of the long guide hole 35a is fitted into it. Similarly, the other engagement protrusions 36b, 36c, and 36d also have stop pins 37 fitted into them. This allows the top panel 36 to slide without separating from the rotating top frame 35.

[0040] Furthermore, inside the long guide holes 35a, 35b, the top panel 36 is biased in the direction of arrow F, which is parallel to the upper surface of the rotating top frame 35 and away from the rotation shaft 25, by compression springs 38 serving as biasing members stretched between the rotating top frame 35 and the engaging protrusions 36a and between the rotating top frame 35 and the engaging protrusions 36b. As a result, in a natural state in which the top panel 36 is not restricted by other members, movement in the direction of arrow F is restricted at positions where the engaging protrusions 36a, 36b, 36c, 36d are in pressure contact with the ends of the corresponding long guide holes 35a, 35b, 35c, 35d in the direction of arrow F.

[0041] The rotating top frame 35 is also configured to detachably hold a basket 70 (FIG. 2) on which process units 10K, 10C, 10M, 10Y, etc. are mounted, a toner cartridge 20, etc., and to fixedly hold a duct 22 (FIG. 1). Note that FIG. 3 shows a state in which the basket 70 equipped with the four process units 10, the toner cartridge 20, etc. are held by the rotating top frame 35 and rotated together with the top cover 102 to the open position.

[0042] On the other hand, the front cover 103 includes a rotating front frame 41 as a second base that is held rotatably around the rotation axis 26 by the housing 60 that constitutes the main body of the image forming apparatus 1, and a front panel 42 as a second cover member that is fixedly held by this rotating front frame 41.

[0043] The main body frame 61 formed integrally with the housing 60 has an upper portion 61a and a front portion 61b, and when the top cover 102 is closed, it mounts the process units 10K, 10C, 10M, 10Y, etc., which are integrally held in the basket 70 (Figure 3), and connects to a drive system provided in the image forming apparatus 1 main body.

[0044] The front surface 61b of the main body frame 61 is formed with a first engagement hole 61c with which a first locking portion 55 as a first engagement portion rotatably held by the rotating top frame 35 engages to maintain the top cover 102 in the closed position when the top cover 102 is rotated to the closed position, as described later, and a second engagement hole 61d with which a second locking portion 56 as a second engagement portion rotatably held by the rotating front frame 41 engages to maintain the front cover 103 in the closed position when the front cover 103 is rotated to the closed position, as described later. The top cover 102 is biased in the counterclockwise direction by a torsion spring (not shown) disposed on the rotation shaft 25.

[0045] FIG. 5(a) is a partially enlarged view of the dotted line area P in FIG. 2, with some of the components removed in order to clearly show the internal configuration, and FIG. 5(b) is a partially enlarged view of the dotted line area P in FIG. 2, with even more components removed than in FIG. 5(a) in order to clearly show the internal configuration.

[0046] As shown in FIG. 5(a), the rotating top frame 35 rotatably supports a first rotating shaft 45 that fixedly holds the first engaging portion 55, and the rotating front frame 41 rotatably supports a second rotating shaft 46 that fixedly holds the second engaging portion 56.

[0047] Furthermore, the first locking portion 55 is biased in a clockwise direction (as viewed from the positive side of the Y direction) by a first torsion spring 51 (see FIG. 1(b)) suspended between the rotating top frame 35, but rotation beyond a predetermined rotation position is restricted by a regulating member (not shown). Similarly, the second locking portion 56 is biased in a clockwise direction (as viewed from the positive side of the Y direction) by a second torsion spring 52 (see FIG. 1(b)) suspended between the rotating front frame 41, but rotation beyond a predetermined rotation position is restricted by a regulating member (not shown).

[0048] The first rotating shaft 45, the first locking portion 55, the first engagement hole 61c, the first torsion spring 51, and the second rotating shaft 46, the second locking portion 56, and the second engagement hole 61d are formed in pairs, left and right, approximately symmetrically with respect to a virtual reference plane (XZ plane) that intersects at the center of the device in the Y-axis direction (see Figures 6(a) and (b)). For this reason, since the configurations and operations of these components formed symmetrically with respect to the left and right are symmetrical, there are cases in which only one of them is described. The second rotating shaft is a common shaft that is integrated on the left and right.

[0049] As shown in Fig. 4(a), a cylindrical positioning abutment member 39 protruding downward from the lower surface of the top panel 36 is fixedly disposed near the tip of the top panel 36 in the direction away from the pivot shaft 25, and a positioning restriction member 43 that abuts against the positioning abutment member 39 is fixedly disposed at the upper end of the front panel 42. As shown in Fig. 4(c), the positioning restriction member 43 is formed with a restricting inclined surface 43b as a second abutment portion against which the tip of the positioning abutment member 39 slides while abutting, as described later, and a tip restriction portion 43a as a first abutment portion that abuts against the side surface of the positioning abutment member 39 to position the top panel 36 in the X direction. As shown in Fig. 4, the restricting inclined surface 43b is a surface that is inclined toward the pivot shaft 26 with respect to the circumferential direction (arrow K direction) of the front panel 42 when the front cover 103 is closed.

[0050] Here, the leading end restricting portion 43a and the restricting inclined surface 43b are formed on the positioning restricting member 43 arranged on the front panel 42, but they can also be appropriately formed on any part of the front cover 103 itself. Also, here, the positioning abutment member 39 is configured to be disposed on the top panel 36, but they can also be appropriately formed on any part of the front cover 103 itself.

[0051] 4(a) in which the top cover 102 and the front cover 103 are both in the closed position, the positioning contact member 39 is in pressure contact with the tip restriction portion 43a of the positioning restriction member 43, as described below, restricting the movement of the top cover 102 in the F direction. Therefore, the top panel 36 is stopped at a position slightly returned in the reverse F direction from the natural state.

[0052] In addition, here, the tip of the top panel 36 and the tip of the front panel 42 are inclined surfaces facing each other, as shown in Figure 4(a), and are configured to face each other with a small gap between them when both are closed.

[0053] Fig. 6(a) is a partial enlarged view of the tip of the top cover 102 shown in Fig. 3, for example, as viewed from diagonally below, and Fig. 6(b) is a partial enlarged view of the tip of the front cover 103 shown in Fig. 3, as viewed from the same direction. However, in Fig. 6(a), the toner cartridge 20 and the like are omitted so that the internal configuration can be seen.

[0054] As shown in the same figures (a) and (b), a pair of positioning abutment members 39 are arranged near the left and right ends of the tip of the top panel 36, and a pair of positioning restricting members 43 are arranged in positions opposite the positioning abutment members 39 as described above, near the left and right ends of the tip of the front panel 42 in the direction away from the pivot axis 26.

[0055] In the above configuration, a description will be given of the sliding operation of the top panel 36 when the top cover 102 and the front cover 103 are opened or closed. Figures 7 and 8 are operation explanatory diagrams for explaining this operation.

[0056] Figure 7(a) shows the state when the top cover 102 is in the open position and the front cover 103 is in the closed position, Figures 7(b) and (c) show the positional relationship between the positioning abutment member 39 and the positioning control member 43 when the top cover 102 is closing, and Figure 7(d) shows the positional relationship between the positioning abutment member 39 and the positioning control member 43 when the top cover 102 reaches the closed position.

[0057] When the top cover 102 is in the open position, the top panel 36 is in a natural state in which the movement restriction by the positioning restriction member 43 arranged on the front cover 103 is released. Therefore, the top panel 36, which is biased by the compression spring 38, is in a state in which the engagement protrusions 36a, 36b, 36c, and 36d (FIG. 4(b)) are in contact with the ends of the long guide holes 35a, 35b, 35c, and 35d of the rotating top frame 35 in the direction of the arrow F. As a result, the top panel 36 is in a state in which it has moved slightly in the direction of the arrow F relative to the rotating top frame 35 compared to when the top cover 102 is in the closed position (FIG. 4(a)).

[0058] When the operator rotates the top cover 102 from this open position in the closing direction (clockwise direction) to close it, the positioning abutment member 39 disposed on the top panel 36 eventually abuts against the restricting inclined surface 43b of the positioning restricting member 43 disposed on the front panel 42, as shown in Fig. 7(b). When the top cover 102 is further pressed down, as shown in Fig. 7(c), the positioning abutment member 39 receives a resisting force in the direction of arrow G, which is opposite to the direction of arrow F, so that the positioning abutment member 39 moves downward along the restricting inclined surface 43b, and at the same time, the top panel 36 moves in the direction of arrow G (-F direction) against the bias of the compression spring 38.

[0059] When the top cover 102 is pressed further, as shown in FIG. 4(d), the positioning restricting member 43 passes through the restricting inclined surface 43b and reaches the tip restricting portion 43a of the positioning restricting member 43 just before the top cover 102 reaches the closed position, and when the top cover 102 reaches the closed position, the top panel 36 remains in that position with its positioning abutment member 39 pressed against the tip restricting portion 43a of the positioning restricting member 43 of the front panel 42, as shown in FIG. 4(a), and its movement is restricted.

[0060] On the other hand, when the tip of the first locking portion 55 of the top cover 102 abuts against the front surface 61b of the main body frame 61 as the top cover 102 reaches the closed position, the tip of the first locking portion 55 rotates and slides counterclockwise against the force of the first torsion spring 51 (Figure 5(b)), and when the top cover 102 eventually reaches the closed position, its tip fits into the first engagement hole 61c of the front surface 61b as shown in Figure 4(a), locking the top cover 102 in the closed position.

[0061] Furthermore, when opening the top cover 102, the operator pulls out the top release lever 31 (see Figure 3) of the top cover 102, which is in the closed position, toward himself, thereby rotating the first locking portion 55 shown in Figure 5 counterclockwise against the force of the first torsion spring 51, thereby releasing the locked state in the closed position.

[0062] Figure 8(a) shows the state when the front cover 103 is in the open position and the top cover 102 is in the closed position, Figures 8(b) and (c) show the positional relationship between the positioning abutment member 39 and the positioning regulating member 43 when the front cover 103 is closing, and Figure 8(d) shows the positional relationship between the positioning abutment member 39 and the positioning regulating member 43 when the front cover 103 has reached the closed position.

[0063] In this state, the top panel 36 is in its natural state. That is, the top panel 36 biased by the compression spring 38 is in a state in which its engagement projections 36a, 36b, 36c, and 36d (FIG. 4(b)) are in contact with the ends of the long guide holes 35a, 35b, 35c, and 35d of the rotating top frame 35 in the direction of the arrow F. As a result, the top panel 36 is in a state in which it has moved slightly in the direction of the arrow F relative to the rotating top frame 35 compared to when the front cover 103 is in the closed position (FIG. 4(a)).

[0064] When the operator rotates the front cover 103 from this open position in the closing direction (counterclockwise) to close it, the positioning restricting member 43 disposed on the front panel 42 eventually approaches the lower part of the positioning abutment member 39 disposed on the top panel 36, as shown in Fig. 8(b). When the front cover 103 is further pushed up, the tip restricting portion 43a of the positioning restricting member 43 abuts against the lower part of the positioning abutment member 39 and further presses it, as shown in Fig. 8(c), so that the top panel 36 starts to move in the direction of arrow G (-F direction) against the bias of the compression spring 38.

[0065] When the front cover 103 is further pressed in, it eventually reaches the closed position as shown in Fig. 4(d). At this stage, the top panel 36 remains in that position with its positioning abutment member 39 in pressure contact with the tip restriction portion 43a of the positioning restriction member 43 of the front panel 42 and restricted in movement, as shown in Fig. 4(a).

[0066] On the other hand, when the tip of the second locking portion 56 of the front cover 103 abuts against the front surface 61b of the main frame 61 as the front cover 103 reaches the closed position, the tip of the second locking portion 56 rotates and slides counterclockwise against the force of the second torsion spring 52 (Figure 5(b)), and when the front cover 103 eventually reaches the closed position, its tip fits into the second engagement hole 61d of the front surface 61b as shown in Figure 4(a), locking the front cover 103 in the closed position.

[0067] Furthermore, when opening the front cover 103, the operator pulls out the front release lever 30 (see Figure 2) of the front cover 103, which is in the closed position, toward himself, thereby rotating the second locking portion 56 shown in Figure 5 counterclockwise against the force of the second torsion spring 52, thereby releasing the locked state in the closed position.

[0068] Since the image forming apparatus 1 is configured and operates as described above, whether the top cover 102 is closed from a state in which the top cover 102 is in the open position and the front cover 103 is in the closed position as shown in FIG. 7(a), or conversely, when the front cover 103 is closed from a state in which the top cover 102 is in the closed position and the front cover 103 is in the open position, as shown in FIG. 4(a), the top panel 36 is biased in the direction of arrow F (which is the same as the -X direction when the top cover 102 is closed), and its movement in the same direction is restricted by the positioning restricting member 43 formed on the front cover 103 with which the positioning abutment member 39 abuts.

[0069] Therefore, even if, for example, a manufacturing error or a shift over time causes a shift in the ±X directions of the rotating top frame 35 relative to the image forming apparatus 1 main body, a shift in the direction of arrow F of the top panel 36 relative to the rotating top frame 35, or even a shift in the closed position of the front cover 103, the relative positional relationship in the X direction between the top panel 36 and the front panel 42 does not change when the top cover 102 and the front cover 103 are closed.

[0070] Variation 1. FIG. 9 is a diagram showing a configuration of a main part of the first modified example of the first embodiment. In the present embodiment, as shown in Fig. 4(a), an example has been shown in which a cylindrical positioning abutment member 39 is disposed on the top panel 36, and a positioning restriction member 43 having a restricting inclined surface 43b (Fig. 4(c)) is disposed on the front panel 42, but in this modified example 1, an abutment member 239 equivalent to the positioning abutment member 39 is disposed on the front panel 42, and a positioning restriction member 243 having a leading end restriction portion 243a and a restricting inclined surface 243b equivalent to the positioning restriction member 43 is disposed on the top panel 36. The other configurations are the same as those of the image forming apparatus 1 of the present embodiment shown in Fig. 4.

[0071] Here, when the front cover 103 is in the closed position and the top cover 102 is closed from the open position to the closed position, the restricting inclined surface 243b as the fourth abutment portion of the positioning restricting member 243 arranged on the top panel 36 receives a resistance and moves in the -F direction, resulting in the state of both the top cover 102 and the front cover 103 being in the closed position as shown in Fig. 9. Then, when the top cover 102 is in the closed position and the front cover 103 is closed from the open position to the closed position, the abutting member 239 arranged on the front panel 42 presses the leading end restricting portion 243a as the third abutment portion of the positioning restricting member 243, moving the top panel 36 in the -F direction to the state shown in Fig. 9.

[0072] In the state shown in Figure 9 where the top cover 102 and the front cover 103 are in the closed position, the top panel 36 is biased in the direction of arrow F (which is the same as the -X direction when the top cover 102 is closed), and its movement in the same direction is restricted by the abutment member 239 formed on the front cover 103 with which the tip regulating portion 243a of the positioning regulating member 243 abuts.

[0073] Therefore, even if, for example, a manufacturing error or a deviation over time causes a shift in the ±X directions of the rotating top frame 35 relative to the image forming apparatus 1 main body, a shift in the direction of arrow F of the top panel 36 relative to the rotating top frame 35, or even a shift in the closed position of the front cover 103, the assumed positional relationship in the X direction between the top panel 36 and the front panel 42 does not change when the top cover 102 and the front cover 103 are closed.

[0074] As described above, according to the image forming apparatus 1 of the present embodiment, the distance (gap) between the top cover 102 and the front cover 103 in the front-rear direction (X direction) when the top cover 102 and the front cover 103 are closed can be always kept constant regardless of manufacturing errors, misalignment over time, etc., so that it is possible to prevent the two from coming into contact with each other and causing inconvenience. In addition, because the distance between the two is always kept constant, deterioration of the design over time can also be prevented.

[0075] In addition, in the above claims and description of the embodiments, words such as "upper," "lower," "left," "right," "front," and "rear" are used, but these are used for convenience and do not limit the absolute positional relationship when the image forming apparatus 1 is positioned. [Industrial Applicability]

[0076] The present invention can be used in image forming apparatuses (such as copiers, facsimiles, printers, and multifunction machines) that form images on media by using an electrophotographic system. [Explanation of symbols]

[0077] 1 image forming apparatus, 4 recording paper, 10 process unit, 11 photosensitive drum, 12 charging roller, 13 print head, 14 developing roller, 15 supply roller, 20 toner cartridge, 22 duct, 25 rotating shaft, 26 rotating shaft, 28 operation panel, 30 front release lever, 31 top release lever, 35 rotating top frame, 35a guide long hole, 35b guide long hole, 35c guide long hole, 35d guide long hole, 36 top panel, 36a engagement protrusion, 36b engagement protrusion, 36c engagement protrusion, 36d engagement protrusion, 37 stop pin, 38 compression spring, 39 positioning abutment member, 41 rotating front frame, 42 front panel, 43 positioning restriction member, 43a leading end restriction portion, 43b Regulatory slope, 45 first rotating shaft, 46 second rotating shaft, 51 first torsion spring, 52 second torsion spring, 55 first locking portion, 56 second locking portion, 60 housing, 61 main body frame, 61a upper portion, 61b front portion, 61c first engagement hole, 61d second engagement hole, 70 basket, 100 image forming portion, 102 top cover, 103 front cover, 110 medium supply portion, 111 paper feed tray, 112 pickup roller, 113 feed roller, 114 retard roller, 115 lifter, 116 registration roller, 117 pressure roller, 118 transport roller, 119 pressure roller, 120 transfer unit, 121 transfer roller, 122 transfer belt, 123 Drive roller, 124 idle roller, 130 fixing device, 131 fixing belt, 132 pressure roller, 140 medium discharge section, 141 discharge roller pair, 142 discharge roller pair, 143 stacker section, 239 contact member, 243 positioning restriction member, 243a leading end restriction section, 243b restriction inclined surface.

Claims

1. A device body, a first cover unit that covers a first surface of the device body in an openable and closable manner; a second cover unit that opens and closes a second surface that intersects with the first surface; and having The first cover unit includes a first base and a first cover member that is movably supported on the first base and covers the first surface, An image forming apparatus, characterized in that when the first cover unit is in a closed position and the second cover unit is closed, the first cover member is moved relative to the first base by the second cover unit in the process of being closed.

2. The second cover unit includes: a first abutment portion that, when the first cover unit is in a closed position and the second cover unit is closed, abuts against the first cover member during the closing process and moves the first cover member relative to the first base portion; a second abutment portion that, when the second cover unit is in a closed position and the first cover unit is closed, abuts against the first cover member during the closing process and moves the first cover member relative to the first base portion; 2. The image forming apparatus according to claim 1, further comprising:

3. the first base portion has a first engagement portion that engages with the device body to hold the first cover unit in a closed position; 3. The image forming apparatus according to claim 1, wherein the second cover unit maintains a spaced-apart state from the first base portion during the process of closing the second cover unit when the first cover unit is in the closed position.

4. the second cover unit has a second engagement portion that engages with the device body to hold the second cover unit in a closed position; 3. The image forming apparatus according to claim 2, wherein when the first cover unit is in a closed position and the second cover unit is closed, the first abutment portion abuts against the first cover member before the second cover unit reaches the closed position.

5. the first base is held by the device body so as to be rotatable about a first rotation axis; 3. The image forming apparatus according to claim 1, wherein the first cover unit has a biasing member that biases the first cover unit against the first base in a direction away from the first rotation shaft.

6. The second cover unit includes a second base and a second cover member fixed to the second base; 3. The image forming apparatus according to claim 2, wherein the first contact portion and the second contact portion are provided on the second cover member.

7. 7. The image forming apparatus according to claim 6, wherein the second base is supported by the apparatus body so as to be rotatable about a second rotation axis.

8. 3. The image forming apparatus according to claim 2, wherein the second contact portion has an inclined surface that is inclined toward a rotation center side with respect to a circumferential direction when the second cover unit is closed.

9. The first cover member includes: a third contact portion that contacts the second cover unit when the second cover unit is closed with the first cover unit in a closed state, and moves the first cover member relative to the first base portion; a fourth contact portion that contacts the second cover unit when the first cover unit is closed in a state in which the second cover unit is closed, and moves the first cover member relative to the first base portion; 2. The image forming apparatus according to claim 1, further comprising:

Images