Sheet conveying device and image forming apparatus

Abstract

A sheet conveying device facilitates the handling of jammed paper. Even when the tip of the guiding portion is disposed near the clamping point of the conveying roller pair, the guiding portion does not interfere with the conveying roller pair during the rotation of the cover, and the guiding portion can be disposed at an appropriate position relative to other conveying roller pairs. The sheet conveying device mounted on the image forming apparatus (1) includes: a movable guiding portion (82) provided on the rear cover (23) and movable between a first position where the sheet is guided to the clamping point of the intermediate discharge rollers (431, 432) and a second position spaced apart from the clamping point along the sheet conveying direction compared to the first position; and a moving mechanism (9) that moves the movable guiding portion (82). When the rear cover (23) moves from the closed position to the open position, the moving mechanism (9) moves the movable guiding portion (82) from the first position to the second position so that the movable guiding portion (82) does not interfere with the conveying roller pair.

Description

Technical Field

[0001] The present invention relates to a sheet conveying device and an image forming device. Background Art

[0002] An image forming device such as a laser printer includes a sheet conveying device having a guiding portion that guides a sheet along a conveying path and a pair of conveying rollers that convey the sheet. The sheet conveyed along the conveying path is guided by the guiding portion to a nip point of the pair of conveying rollers. Here, in order to suppress paper jams of the sheet in the pair of conveying rollers, it is preferable to dispose the tip of the guiding portion near the nip point of the pair of conveying rollers.

[0003] In addition, a rotatable cover for paper jam processing or the like is provided in the device main body of the image forming device, and the above-described guiding portion is provided on the cover. Therefore, when the tip of the guiding portion is disposed near the nip point of the pair of conveying rollers, the tip of the guiding portion contacts the conveying roller when the cover is rotated.

[0004] As a countermeasure, Patent Document 1 discloses the following structure: The guiding portion is provided on the device main body, the bearing of the guiding portion is elliptical, and after the guiding portion is separated from the pair of conveying rollers in response to the rotation of the cover, the guiding portion is rotated. In addition, Patent Document 2 discloses a structure in which the bearing of the cover is formed in an elongated hole shape, thereby reducing the rotation locus of the cover.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2012-136311

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 2017-132231

[0009] Problems to be Solved by the Invention

[0010] However, in the structure of Patent Document 1, when the cover is opened, the guiding portion remains on the device main body side. Therefore, it is difficult to perform paper jam processing as compared with the structure in which the guiding portion is provided on the cover side. In addition, in the structure of Patent Document 2, the entire guiding portion moves together with the cover. Therefore, the guiding portion cannot be disposed at an appropriate position with respect to other pairs of conveying rollers. Summary of the Invention

[0011] An object of the present invention is to provide a sheet conveying device that facilitates jam processing by providing a guiding portion on a cover, and even when the tip of the guiding portion is disposed near the clamping point of the conveying roller pair, the guiding portion does not interfere with the conveying roller pair during rotation of the cover, and the guiding portion can be disposed at an appropriate position relative to other conveying roller pairs. Another object of the present invention is to provide an image forming apparatus including the sheet conveying device.

[0012] Technical means for solving technical problems

[0013] The sheet conveying device of the present invention includes: a device main body having an opening; a conveying roller pair provided in the device main body for conveying a sheet guided along a conveying path; a cover rotatably provided on the device main body between a closed position covering the opening and an open position opening the opening; a movable guiding portion provided on the cover and movable between a first position for guiding the sheet to a clamping point of the conveying roller pair and a second position away from the clamping point along the sheet conveying direction compared to the first position; and a moving mechanism for moving the movable guiding portion. When the cover moves from the closed position toward the open position, the moving mechanism moves the movable guiding portion from the first position to the second position so that the movable guiding portion does not interfere with the conveying roller pair.

[0014] According to the above structure, jam processing is facilitated by providing the movable guiding portion on the cover. In addition, even when the tip of the movable guiding portion is disposed near the clamping point of the conveying roller pair, the movable guiding portion does not interfere with the conveying roller pair during rotation of the cover.

[0015] In addition, in the above structure, the device main body may have a bracket for supporting the conveying roller pair. The moving mechanism includes: a biasing member for biasing the movable guiding portion from the second position toward the first position; a first engaging portion provided on the bracket; and a second engaging portion provided on the movable guiding portion. When the cover moves from the closed position toward the open position, the second engaging portion slides in contact with the first engaging portion, so that the movable guiding portion moves from the first position to the second position against the biasing force of the biasing member.

[0016] According to the above structure, since the first engaging portion that slides in contact with the second engaging portion is provided on the bracket that supports the conveying roller pair, the movable guiding portion can be accurately positioned with respect to the clamping point of the conveying roller pair.

[0017] In addition, in the above-described structure, a downstream guide portion for guiding the sheet along the conveyance path may also be provided. The downstream guide portion is integrally provided with the movable guide portion on the side opposite to the movable guide portion across the pair of conveyance rollers.

[0018] According to the above-described structure, by integrally providing the downstream guide portion and the movable guide portion, it is possible to improve the positional accuracy of the downstream guide portion with respect to the movable guide portion and to reduce the number of components.

[0019] The image forming apparatus of the present invention includes: the above-described sheet conveyance device; an image forming portion that forms an image on the conveyed sheet; a fixing portion that fixes the image to the sheet; and a re-conveyance roller pair that re-conveys the sheet that has passed through the fixing portion from the image forming portion, been conveyed to the pair of conveyance rollers, and turned from the pair of conveyance rollers to the image forming portion. The sheet conveyance device includes another guide portion that is provided on the cover and guides the sheet along the conveyance path. The movable guide portion is provided along the conveyance path between the fixing portion and the pair of conveyance rollers. The other guide portion is provided along the conveyance path between the pair of conveyance rollers and the re-conveyance roller pair.

[0020] According to the above-described structure, the above-described sheet conveyance device can be applied to an image forming apparatus capable of duplex printing. Also, by providing the other guide portion and the movable guide portion on the cover, paper jam processing becomes easy. In addition, even if the tip of the movable guide portion is disposed near the clamping point of the pair of conveyance rollers, the movable guide portion does not interfere with the pair of conveyance rollers when the cover rotates. Further, since the other guide portion does not move, the other guide portion can be disposed at an appropriate position with respect to the re-conveyance roller pair.

[0021] In the above-described structure, the other guide portion may also have a first guide rib extending in the sheet conveyance direction, and the movable guide portion has a second guide rib extending in the sheet conveyance direction. The second guide rib is disposed at a position different from that of the first guide rib in the width direction orthogonal to the sheet conveyance direction. When viewed from the width direction, the second guide rib is disposed at a position overlapping the first guide rib.

[0022] According to the above-described structure, the transfer of the sheet between the first guide rib and the second guide rib becomes smooth.

[0023] Effects of the Invention

[0024] According to the present invention, the handling of the paperboard is made easier by providing a movable guide portion on the cover. In addition, by providing a moving mechanism, even if the tip of the movable guide portion is disposed near the clamping point of the pair of conveying rollers, the movable guide portion does not interfere with the pair of conveying rollers during the rotation of the cover. Further, since the other guide portions do not move, the other guide portions can be disposed at appropriate positions relative to the other pairs of conveying rollers. Brief Description of the Drawings

[0025] Figure 1 is a perspective view of an image forming apparatus according to an embodiment.

[0026] Figure 2 is Figure 1 a schematic view of a central cross section of the image forming apparatus.

[0027] Figure 3 is a front view of the rear cover.

[0028] Figure 4 is a right side view of the rear cover.

[0029] Figure 5 is Figure 3 a sectional view taken along line A-A of

[0030] Figure 6 is Figure 3 a sectional view taken along line B-B of

[0031] Figure 7 is Figure 3 a sectional view taken along line C-C of

[0032] Figure 8 is a central sectional view of the periphery of the rear cover in a state where the rear cover is in a closed position.

[0033] Figure 9 is a view showing a state where the rear cover is near the closed position in Figure 8

[0034] Figure 10 is a sectional view of the periphery of the moving mechanism in a state where the rear cover is in a closed position.

[0035] Figure 11 is a view showing a state where the rear cover is near the closed position in Figure 10

[0036] Figure 12 is a central sectional view of the periphery of the rear cover of an image forming apparatus according to a modified example.

[0037] Symbol Description

[0038] 1, 10 Image forming apparatus

[0039] 2 Apparatus main body

[0040] 5 Image forming unit

[0041] 9 Moving mechanism

[0042] 22 Opening

[0043] 23 Rear cover (cover)

[0044] 26 Bracket

[0045] 53 Fixing unit

[0046] 81 First guiding unit (other guiding unit)

[0047] 82 Second guiding unit (movable guiding unit)

[0048] 83 Third guiding unit (downstream guiding unit)

[0049] 91, 95 Biasing members

[0050] 92 First engaging portion

[0051] 93 Second engaging portion

[0052] 431, 432 Intermediate discharge rollers (conveyor roller pair)

[0053] 611, 612 Intermediate conveying rollers (re-conveying roller pair)

[0054] 811 First guiding rib

[0055] 821 Second guiding rib

[0056] P1 Conveying path

[0057] P2 Re-conveying path (conveying path)

[0058] S Sheet Detailed implementation manners

[0059] In the following embodiments, as an application example of the sheet conveying device, an image forming apparatus will be taken as an example for explanation.

[0060] [Overall structure of the image forming apparatus]

[0061] Figure 1 is a perspective view of an image forming apparatus 1 according to an embodiment, Figure 2 is Figure 1 a schematic diagram of a central cross-section of the image forming apparatus 1. In the following description, Figure 1Based on the state in which the illustrated image forming apparatus 1 is set to be usable, with the side where the rear cover 23 is provided as the rear and the opposite side as the front, the left - right direction is defined by observing the image forming apparatus 1 from the front side, and with the discharge tray 21 side of the image forming apparatus 1 as the upper side and the opposite side as the lower side, thereby determining each direction. In the present embodiment, the left - right direction is the width direction orthogonal to the sheet conveyance direction.

[0062] As Figure 1 shown, the exterior of the image forming apparatus 1 is formed by a device main body 2 of a substantially rectangular parallelepiped housing. A discharge tray 21 is provided on the upper surface of the device main body 2, and the discharge tray 21 supports the sheet on which an image is formed. An opening 22 is formed on the rear surface of the device main body 2.

[0063] A rear cover 23, which is an example of a cover, is provided at the opening 22 of the device main body 2. The rear cover 23 is rotatable about a rotation shaft portion 24 (refer to Figure 2 ) extending in the left - right direction at the lower end between a closed position ([[]] Figure 2 state) covering the opening 22 and an open position ([[]] Figure 1 state) opening the opening 22. When a sheet jams near the opening 22, the jammed sheet can be removed through the opening 22 by opening the rear cover 23.

[0064] As Figure 2 shown, the image forming apparatus 1 is a color laser printer that forms images of multiple colors on a sheet S such as paper or an OHP sheet by an electrophotographic method. A sheet cassette 3, a conveyance unit 4, an image forming unit 5, a fixing unit 53, a re - conveyance unit 6, and a drive unit 7 are housed in the device main body 2. In the device main body 2, generally: the image forming unit 5 is disposed in the upper part and the central part, the fixing unit 53 is disposed behind the image forming unit 5, the conveyance unit 4 is disposed below and behind the image forming unit 5, the sheet cassette 3 is disposed below the conveyance unit 4, the re - conveyance unit 6 is disposed across the front part and the rear part of the device main body 2 and below the sheet cassette 3, and the drive unit 7 is disposed between the image forming unit 5 and the sheet cassette 3.

[0065] In addition, an opening 25 serving as an insertion port for the sheet cassette 3 is formed in the lower part of the front surface of the device main body 2. The sheet cassette 3 is a box - shaped body with an upper opening having a sheet storage portion 31 and supports a plurality of overlapping sheets S. By moving the sheet cassette 3 in the front - rear direction through the opening 25, the sheet cassette 3 can be inserted and removed relative to the device main body 2.

[0066] The conveying unit 4 is composed of components arranged along the conveying path P1, and conveys the sheet S along the conveying path P1. The conveying path P1 is a path that connects the sheet cassette 3 via the image forming unit 5 to the discharge tray 21. The conveying unit 4 is successively composed of a supply unit 41, a belt conveying unit 42, and a discharge unit 43 from the upstream side in the conveying direction of the conveying path P1.

[0067] The supply unit 41 includes a supply roller 411, a separation roller 412, a separation pad 413, conveying rollers 414 and 415, and registration rollers 416 and 417. The sheet S accommodated in the sheet cassette 3 is sent one by one to the conveying path P1 through the supply roller 411, the separation roller 412, and the separation pad 413. The sheet S sent to the conveying path P1 is conveyed toward the image forming unit 5 through the conveying rollers 414 and 415 and the registration rollers 416 and 417.

[0068] The belt conveying unit 42 includes a driving roller 421 that rotates in conjunction with the image forming unit 5, a driven roller 422 that is arranged at a position separated from the driving roller 421 and is capable of rotating, and a conveyor belt 423 wound between the driving roller 421 and the driven roller 422. And, by rotating the conveyor belt 423 with the sheet S placed thereon, the sheet S is conveyed along the conveying path P1, sent below the drum unit 51 of the image forming unit 5, and then sent to the fixing unit 53.

[0069] The discharge unit 43 includes intermediate discharge rollers 431 and 432 and discharge rollers 433 and 434 that are a pair of conveying rollers disposed between the branch P11 of the conveying path P1 and the discharge tray 21. In a state where the rear cover 23 is in the closed position, the inner surface of the rear cover 23 constitutes a part of the conveying path P1.

[0070] The intermediate discharge rollers 431 and 432 and the discharge rollers 433 and 434 are turning rollers configured to be able to switch between rotation in the forward direction and rotation in the reverse direction. When discharging the sheet S conveyed from the fixing unit 53 onto the discharge tray 21, the intermediate discharge rollers 431 and 432 and the discharge rollers 433 and 434 rotate forward. When reversing the sheet S and conveying it to the re-conveying path P2, the intermediate discharge rollers 431 and 432 and the discharge rollers 433 and 434 rotate in the reverse direction.

[0071] In the present embodiment, the image forming unit 5 adopts an electrophotographic method. In addition, an image forming method such as a thermal method or an inkjet method can also be adopted. The image forming unit 5 is a so-called direct tandem type device capable of color printing, and includes four drum units 51 arranged in parallel in the front-rear direction and an exposure LED head 52.

[0072] Each drum unit 51 is provided corresponding to the toner of the four colors: black, yellow, magenta, and cyan. Each drum unit 51 includes: a photosensitive drum 511; a developing roller 512; and transfer rollers 513 disposed at respective positions opposite to the photosensitive drum 511 with the conveyor belt 423 interposed therebetween.

[0073] In the image forming unit 5 configured as described above, each photosensitive drum 511 uniformly charged by a charger is selectively exposed by an exposure LED head 52. Through this exposure, charges are selectively removed from the surface of each photosensitive drum 511, thereby forming an electrostatic latent image on the surface of each photosensitive drum 511.

[0074] A developing bias is applied to each developing roller 512. When the electrostatic latent image formed on each photosensitive drum 511 faces each developing roller 512, toner is supplied from each developing roller 512 to the electrostatic latent image through the potential difference between the electrostatic latent image and each developing roller 512. As a result, a toner image is formed on the surface of each photosensitive drum 511.

[0075] The sheet S conveyed toward the image forming unit 5 is conveyed by the conveyor belt 423 and sequentially passes between the conveyor belt 423 and each photosensitive drum 511. And when facing the sheet S, the toner image on the surface of the photosensitive drum 511 is transferred to the sheet S by the transfer bias applied to the transfer roller 513.

[0076] The fixing unit 53 is disposed downstream in the conveying direction of the four photosensitive drums 511 in the conveying path P1. The fixing unit 53 includes a heating roller 531 and a pressure roller 532 that is pressed against the heating roller 531. The heating roller 531 is disposed on the image forming surface side of the sheet S and is driven to rotate synchronously with the conveyor belt 423, applying a conveying force to the sheet S while heating the toner.

[0077] On the other hand, the pressure roller 532 is disposed on the opposite side of the heating roller 531 with the sheet S interposed therebetween, and presses the sheet S toward the heating roller 531 side. As a result, the pressure roller 532 receives a rotational force from the heating roller 531 via the sheet S in contact with the heating roller 531 and rotates idly.

[0078] In addition, the fixing unit 53 includes fixing discharge rollers 533 and 534, which are disposed downstream in the conveying direction of the sheet S compared to the heating roller 531 and the pressure roller 532.

[0079] The sheet S transferred with the toner image by the image forming unit 5 is conveyed to the fixing unit 53. And when passing between the heating roller 531 and the pressure roller 532, the toner image is thermally fixed to the sheet S. The sheet S with the thermally fixed toner image is clamped by the fixing discharge rollers 533 and 534 and conveyed to the intermediate discharge rollers 431 and 432.

[0080] The refeeding unit 6 is composed of components arranged along the refeeding path P2, and conveys the sheet S along the refeeding path P2. The refeeding path P2 is a path that branches from a branch portion P11 between the fixing unit 53 and the intermediate discharge rollers 431 and 432 in the conveying path P1, passes under the sheet cassette 3, and merges at a merging portion P12 between the sheet cassette 3 and the image forming unit 5.

[0081] The refeeding unit 6 includes intermediate conveying rollers 611 and 612 as an example of a pair of refeeding rollers and a chute unit 63 along the conveying direction of the refeeding path P2. In a state where the rear cover 23 is in the closed position, the inner surface of the rear cover 23 constitutes a part of the refeeding path P2. The intermediate conveying rollers 611 and 612 are conveying rollers arranged at the opening 22 and conveying the sheet toward the chute unit 63.

[0082] The chute unit 63 includes a plurality of conveying rollers 631 to 636. The plurality of conveying rollers 631 to 636 are provided under the sheet cassette 3 and are used to guide the sheet S along the refeeding path P2. The chute unit 63 conveys the sheet S conveyed from the intermediate conveying rollers 611 and 612 to the merging portion P12. The sheet S re-fed from the merging portion P12 to the image forming unit 5 forms an image on the other side after passing through the image forming unit 5, and is discharged to the discharge tray 21 through the discharge unit 43.

[0083] In this way, in the image forming apparatus 1, the sheet S having an image formed on one side by the image forming unit 5 is re-fed to the image forming unit 5 through the refeeding path P2 to form an image on the other side of the sheet S, so that so-called duplex printing can be performed.

[0084] The driving unit 7 is composed of a motor or the like and is arranged above the chute unit 63. The driving force of the driving unit 7 is transmitted to each part via a driving transmission mechanism.

[0085] In such an image forming apparatus 1, a structure in which a guiding portion is provided on the rear cover 23 to facilitate paper jam processing will be described. In addition, a moving mechanism that does not cause the guiding portion to interfere with the intermediate discharge rollers 431 and 432 when the rear cover 23 rotates even when the tip of the guiding portion is arranged near the clamping point of the intermediate discharge rollers 431 and 432 will also be described. Further, a structure that can arrange the guiding portion at an appropriate position relative to the intermediate conveying rollers 611 and 612 will also be described.

[0086] [Guiding Portion and Moving Mechanism]

[0087] Figure 3 is a front view of the rear cover 23, Figure 4 is a right side view of the rear cover 23, Figure 5 is Figure 3 a sectional view taken along line A-A of Figure 6 isFigure 3 Cross-sectional view taken along line B-B, Figure 7 is Figure 3 Cross-sectional view taken along line C-C, Figure 8 is a central cross-sectional view of the periphery of the rear cover 23 in a state where the rear cover 23 is in the closed position, Figure 9 is a view showing Figure 8 a state where the rear cover 23 is near the closed position in Figure 10 is a cross-sectional view of the periphery of the moving mechanism 9 in a state where the rear cover 23 is in the closed position, Figure 11 is a view showing Figure 10 a state where the rear cover 23 is near the closed position in

[0088] <Guide portion>

[0089] As shown in Figure 3 , Figure 4 and Figure 8 , a guide portion 8 is provided on the rear cover 23, and the guide portion 8 guides the sheet S along the conveyance path P1 and the re-conveyance path P2. In addition, a moving mechanism 9 is provided on the rear cover 23 and the apparatus main body 2, and the moving mechanism 9 prevents the guide portion 8 from interfering with the intermediate discharge rollers 431 and 432 when the rear cover 23 rotates.

[0090] The guide portion 8 includes a first guide portion 81, a second guide portion 82, and a third guide portion 83. The first guide portion 81 is fixed to the inner surface of the rear cover 23 by a threaded member 84. The first guide portion 81 has a plurality of first guide ribs 811, and the plurality of first guide ribs 811 are provided along the conveyance path P1 and the re-conveyance path P2 between the intermediate discharge rollers 431 and 432 and the intermediate conveyance rollers 611 and 612, and extend in the sheet conveyance direction. The sheet S is guided by sliding contact with the first guide ribs 811.

[0091] The lower end portion 811A of the first guide rib 811 extends to the vicinity of the clamping point of the intermediate conveyance rollers 611 and 612. Thus, since the first guide portion 81 does not move, the first guide ribs 811 can be arranged at appropriate positions relative to the intermediate conveyance rollers 611 and 612. Thereby, paper jams in the intermediate conveyance rollers 611 and 612 can be suppressed.

[0092] In addition, as shown in Figure 8 , the rotation shaft portion 24 of the rear cover 23 is located behind the intermediate conveyance rollers 611 and 612. Therefore, the lower end portion 811A of the first guide rib 811 located above the intermediate conveyance rollers 611 and 612 does not interfere with the intermediate conveyance rollers 611 and 612 when the rear cover 23 is opened and closed.

[0093] As shown in Figure 3 , Figure 4 and Figure 8As shown, the second guiding portion 82 has a plurality of second guiding ribs 821, which are arranged along the conveying path P1 between the fixing portion 53 and the intermediate discharge rollers 431 and 432 and extend in the sheet conveying direction. The sheet S is guided by sliding contact with the second guiding ribs 821.

[0094] The second guiding portion 82 is movably provided on the first guiding portion 81. Specifically, as Figure 6 shown, the second guiding portion 82 has: a cylindrical protrusion 823 protruding rightward from the right surface of its left wall portion 822 and a cylindrical protrusion 825 protruding leftward from the left surface of its right wall portion 824. The first guiding portion 81 has: a groove portion 813 extending in the vertical direction formed on the left surface of its left wall portion 812 and a groove portion 815 extending in the vertical direction formed on the right surface of its right wall portion 814.

[0095] And, by engaging the protrusion 823 with the groove portion 813 and sliding in the vertical direction, and engaging the protrusion 825 with the groove portion 815 and sliding in the vertical direction, the second guiding portion 82 slides in the vertical direction relative to the first guiding portion 81. Thus, the second guiding portion 82 can move between a first position, which is the position for guiding the sheet S to the clamping point of the intermediate discharge rollers 431 and 432 ( Figure 8 the position shown), and a second position, which is a position that is lower than the clamping point in the sheet conveying direction compared to the first position ( Figure 9 the position shown).

[0096] As Figure 3 shown, the second guiding ribs 821 are arranged at different positions in the left-right direction from the first guiding ribs 811. In addition, as Figure 5 shown, when viewed from the right, the lower end portion 821A of the second guiding ribs 821 is arranged at a position overlapping the first guiding ribs 811.

[0097] Thus, the transfer of the sheet S between the first guiding ribs 811 and the second guiding ribs 821 becomes smooth. In addition, the second guiding ribs 821 may be arranged at the same position as the first guiding ribs 811 in the left-right direction, or may be arranged at a position that does not overlap the first guiding ribs 811 when viewed from the right.

[0098] As Figure 3 、 Figure 4 and Figure 8 shown, the third guiding portion 83 is integrally provided with the second guiding portion 82 on the side opposite to the second guiding portion 82, i.e., above, across the intermediate discharge rollers 431 and 432. The third guiding portion 83 has a plurality of third guiding ribs 831 extending in the sheet conveying direction. The sheet S is guided by sliding contact with the third guiding ribs 831.

[0099] By integrally providing the third guide portion 83 with the second guide portion 82, the positional accuracy of the third guide portion 83 relative to the second guide portion 82 can be improved, and the number of components can be reduced. In addition, the third guide portion 83 may be separate from the second guide portion 82.

[0100] Thus, by providing the first guide portion 81, the second guide portion 82, and the third guide portion 83 on the rear cover 23, during paper jam processing, when the rear cover 23 is in the open position, a part of the conveyance path P1 and the re-conveyance path P2 opposite to the rear cover 23 is opened, and thus paper jam processing can be easily performed.

[0101] <Moving mechanism>

[0102] As Figure 10 and Figure 11 shown, the apparatus main body 2 has brackets 26 that support the intermediate discharge rollers 431 and 432 and that are a part of the moving mechanism 9. The brackets 26 are provided at the left and right ends of the apparatus main body 2 and support the rotary shaft portions 431A and 432A of the intermediate discharge rollers 431 and 432.

[0103] The moving mechanism 9 is a mechanism that, when the rear cover 23 moves from the closed position toward the open position, moves the second guide portion 82 from the first position to the second position so that the second guide portion 82 does not interfere with the intermediate discharge rollers 431 and 432. As Figure 3 , Figure 7 , Figure 10 and Figure 11 shown, the moving mechanism 9 has a biasing member 91, a first engaging portion 92, and a second engaging portion 93.

[0104] The biasing member 91 is a member that biases the second guide portion 82 from the second position toward the first position. As the biasing member 91, an elastic body such as a Figure 3 , Figure 7 and Figure 10 shown compression coil spring or rubber can be used. The biasing member 91 is disposed at two positions on the left and right. The lower end portion of the biasing member 91 abuts against the upper surfaces 81A on the left and right of the first guide portion 81, and the upper end portion of the biasing member 91 abuts against the lower surfaces 82A on the left and right of the second guide portion 82.

[0105] The first engaging portion 92 is an engaging portion provided on the bracket 26. As Figure 10 and Figure 11 shown, the first engaging portion 92 in the present embodiment is a recess formed in the lower surface of the bracket 26 and has a first surface 921 and a second surface 922. The first surface 921 is a horizontal surface located below the intermediate discharge roller 432. The second surface 922 is an inclined surface that extends rearward and downward from the rear end of the first surface 921.

[0106] The second engaging portion 93 is an engaging portion provided on the second guiding portion 82. As Figure 3 , Figure 10 and Figure 11 shown, the second engaging portion 93 of the present embodiment is a convex portion formed on the upper surface of the protruding portions 826 protruding forward at the left and right ends of the second guiding portion 82. The second engaging portion 93 has a third surface 931, a fourth surface 932, and a fifth surface 933.

[0107] As Figure 10 shown, when the rear cover 23 is in the closed position, the third surface 931 is a horizontal surface that abuts against the first surface 921. In addition, the fourth surface 932 is an inclined surface that extends forward and downward from the front end of the third surface 931. The fifth surface 933 is an inclined surface that extends backward and downward from the rear end of the third surface 931.

[0108] As Figure 10 shown, with the structure of the moving mechanism 9 like this, when the rear cover 23 is in the closed position, the third surface 931 of the second engaging portion 93 abuts against the first surface 921 of the first engaging portion 92, and the second guiding portion 82 is in the first position due to the biasing force of the biasing member 91. When the rear cover 23 is rotated toward the open position from this state, as the protruding portion 826 moves rearward, the third surface 931 moves rearward while slidingly contacting the first surface 921.

[0109] Next, as Figure 11 shown, as the fifth surface 933 moves rearward while slidingly contacting the second surface 922, the protruding portion 826 is pressed down by the second surface 922. In Figure 11 , the second guiding portion 82 is pressed down against the biasing force of the biasing member 91 and is in the second position.

[0110] Next, when the rear cover 23 is further rotated toward the open position from the Figure 11 state, the third surface 931 slidingly contacts the second surface 922, and then, the fourth surface 932 slidingly contacts the second surface 922. As a result, the second guiding portion 82 returns to the first position due to the biasing force of the biasing member 91.

[0111] That is, as Figure 10 and Figure 11 shown, when the rear cover 23 starts to move from the closed position toward the open position, by the sliding contact between the second engaging portion 93 and the first engaging portion 92, the second guiding portion 82 moves from the first position to the second position against the biasing force of the biasing member 91.

[0112] In this way, as Figure 8 and Figure 9As shown, when the rear cover 23 starts to move from the closed position toward the open position, it moves from the first position to the second position through the second guiding portion 82, so that the upper end portion 821B of the second guiding rib 821 moves away from the intermediate discharge roller 432.

[0113] Accordingly, even if the upper end portion 821B of the second guiding rib 821 is disposed near the clamping point of the intermediate discharge rollers 431 and 432, the upper end portion 821B of the second guiding rib 821 will not interfere with the intermediate discharge roller 432 during the rotation of the rear cover 23. On the other hand, when the rear cover 23 moves from the open position to the closed position, the operation is opposite to the above.

[0114] In addition, by disposing the first engaging portion 92 that slidably contacts the second engaging portion 93 on the bracket 26 that supports the intermediate discharge rollers 431 and 432 as described above, the second guiding portion 82 can be accurately positioned with respect to the clamping point of the intermediate discharge rollers 431 and 432. In addition, the first engaging portion 92 may be disposed at a portion other than the bracket 26 of the apparatus main body 2.

[0115] In addition, contrary to the structure of the first engaging portion 92 and the second engaging portion 93 described above, the first engaging portion 92 may be configured as a convex portion and the second engaging portion 93 may be configured as a concave portion.

[0116] In addition, in the above-described embodiment, the case where the opening 22 is formed on the rear surface of the apparatus main body 2 has been described as an example. However, the opening 22 may be formed on the front surface, the right surface, the left surface, or the upper surface of the apparatus main body 2. And a cover is provided on the surface where the opening 22 is formed. In this case, the target of the second guiding portion provided on the cover for guiding the sheet may not be the intermediate discharge rollers 431 and 432, but may be other conveying rollers facing the opening.

[0117] In the above-described embodiment, the image forming apparatus has been described as an example. However, the present invention can also be applied to apparatuses other than the image forming apparatus such as an image reading apparatus as long as it is a sheet conveying apparatus having a structure for conveying a sheet within an apparatus main body having an opening.

[0118] [Modification Example]

[0119] Figure 12 It is a central cross-sectional view around the rear cover 23 of the image forming apparatus 10 of the modification example. The difference between the image forming apparatus 10 of the modification example and the above-described image forming apparatus 1 is that the second guiding portion 82 is rotatably provided on the inner surface of the first guiding portion 81.

[0120] As a structure that enables the second guide portion 82 to rotate, the image forming apparatus 10 includes a rotation shaft portion 1825, a biasing member 95, and an abutting portion 28. The rotation shaft portion 1825 is a shaft portion that extends in the left-right direction from the second guide portion 82 and is rotatably supported by the first guide portion 81. The rotation shaft portion 1825 is located behind the intermediate discharge rollers 431 and 432.

[0121] The biasing member 95 is a member that biases the second guide portion 82 from the second position toward the first position. As the biasing member 95, an elastic body such as a compression coil spring or rubber as shown can be used. Figure 12 The biasing member 95 is disposed at two positions on the left and right of the upper end of the third guide portion 83 that is integral with the second guide portion 82. And, the rear end of the biasing member 95 is fixed to the third guide portion 83. The abutting portion 28 is provided on the apparatus main body 2. The abutting portion 28 is provided at a position that abuts against the front end of the biasing member 95 when the rear cover 23 is in the closed position.

[0122] Accordingly, when the rear cover 23 is in the closed position, the second guide portion 82 is in the first position ( Figure 12 the position shown). And, when the rear cover 23 starts to rotate from the closed position to the open position, the biasing member 95 separates from the abutting portion 28. Accordingly, the second guide portion 82 rotates about the rotation shaft portion 1825 by its own weight in a direction away from the intermediate discharge roller 432 toward the upper end portion 821B of the second guide rib 821.

[0123] Accordingly, similar to the image forming apparatus 1 described above, even if the upper end portion 821B of the second guide rib 821 is disposed near the clamping point of the intermediate discharge rollers 431 and 432, the upper end portion 821B of the second guide rib 821 does not interfere with the intermediate discharge roller 432 when the rear cover 23 rotates.

Claims

1. A sheet conveying device, characterized in that, Comprising: A device main body having an opening; A pair of conveying rollers provided on the device main body and conveying a sheet guided along a conveying path; A cover rotatably provided on the device main body between a closed position covering the opening and an open position opening the opening; A movable guiding portion provided on the cover and movable between a first position guiding the sheet to a clamping point of the pair of conveying rollers and a second position spaced from the clamping point along the sheet conveying direction compared to the first position; And A moving mechanism for moving the movable guiding portion, When the cover moves from the closed position toward the open position, the moving mechanism moves the movable guiding portion from the first position to the second position so that the movable guiding portion does not interfere with the pair of conveying rollers, The device main body has a bracket for supporting the pair of conveying rollers, The moving mechanism has: A biasing member for biasing the movable guiding portion from the second position toward the first position; A first engaging portion provided on the bracket; And A second engaging portion provided on the movable guiding portion, When the cover moves from the closed position toward the open position, the second engaging portion slidably contacts the first engaging portion, so that the movable guiding portion moves from the first position to the second position against the biasing force of the biasing member.

2. The sheet conveying device according to claim 1, characterized in that, It comprises a downstream guiding portion for guiding the sheet along the conveying path, and the downstream guiding portion is integrally provided with the movable guiding portion on a side opposite to the movable guiding portion with the pair of conveying rollers interposed therebetween.

3. An image forming device, characterized in that, Comprising: The sheet conveying device according to claim 1 or 2; An image forming portion for forming an image on the conveyed sheet; A fixing portion for fixing the image on the sheet; And A pair of re-conveying rollers for re-conveying the sheet that has passed through the fixing portion from the image forming portion, been conveyed to the pair of conveying rollers, and turned from the pair of conveying rollers to the image forming portion, The sheet conveying device is provided with another guiding portion provided on the cover and guiding the sheet along the conveying path, The movable guiding portion is provided along the conveying path between the fixing portion and the pair of conveying rollers, The other guiding portion is provided along the conveying path between the pair of conveying rollers and the pair of re-conveying rollers.

4. The image forming device according to claim 3, characterized in that, The other guiding portion has a first guiding rib extending in the sheet conveying direction, The movable guiding portion has a second guiding rib extending in the sheet conveying direction, and the second guiding rib is arranged at a position different from the first guiding rib in the width direction orthogonal to the sheet conveying direction, When viewed from the width direction, the end portion of the second guiding rib is arranged at a position overlapping the first guiding rib.

Images