Image forming device

By introducing an intercepting member structure into the image forming device and switching the intercepting state according to the paper movement direction, the paper jam problem during double-sided printing is solved, the structural design is simplified, the cost is reduced, and the machine body is miniaturized.

CN223427001UActive Publication Date: 2025-10-10ZHUHAI PANTUM ELECTRONICS CO LTD
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Patent Information

Application Number
CN202422991842.X
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-12-04
Publication Date
2025-10-10
Estimated Expiration
2034-12-04

AI Technical Summary

Technical Problem

When printing on both sides of a paper, the discharge mechanism of an existing image forming device is prone to paper jams due to electrostatic adsorption. Adding an additional paper path to solve this problem increases complexity and cost, which is not conducive to miniaturization of the device.

Method used

The interception component structure includes an interception part and a trigger part. The interception state is switched by changing the movement direction of the medium, preventing the discharged paper from returning during double-sided printing, avoiding electrostatic adsorption, simplifying the structure and reducing costs.

Benefits of technology

It effectively prevents paper jams when paper is returned, simplifies structural design, reduces costs, eliminates the need for an additional paper path, and facilitates miniaturization of the machine body.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model discloses an image forming device. The image forming device comprises an imaging unit; a discharge mechanism; a bearing unit; the discharge mechanism includes: a discharge roller that nips and transports the medium; when the discharge roller rotates forward, the medium is discharged in the first direction. When the medium needs to be overturned, the discharging roller rotates reversely to enable the medium to return in the second direction and enter the image forming device again; the intercepting piece is movably arranged in the discharging mechanism and can receive power of the medium, and the intercepting piece comprises an intercepting part and a triggering part which are connected with each other; the intercepting part is used for stopping discharged media from entering the discharging mechanism, and the triggering part is used for transmitting driving force to the intercepting part; in the first direction, the trigger part is located on the upstream side of the interception part. The paper clamping problem caused by redundant paper adsorption during paper returning can be prevented, a special driving device does not need to be arranged through the intercepting piece, the cost is low, an additional paper path does not need to be arranged, and miniaturization of a machine body is facilitated.
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Description

Technical Field

[0001] The utility model relates to the technical field of electronic image forming, in particular to a structure for discharging paper in an image forming device. Background Art

[0002] An image forming apparatus is a device that forms an image on a printing medium according to an input signal. Examples of image forming apparatuses include printers, copiers, fax machines, and multifunction printers that integrate the functions of printers, copiers, and fax machines.

[0003] When printing or scanning on one side of the paper, the discharge mechanism rotates forward until the paper is completely discharged to the outside of the machine; when printing on both sides of the paper, the discharge mechanism rotates forward first, and when the tail of the paper leaves the fixing and has not yet been discharged, the discharge mechanism switches to reverse rotation, and the paper with the front portrait printed is sucked into the duplex printing paper path in the printer again. After passing through the duplex printing paper path, the back of the paper goes through the transfer and fixing process again to reach the discharge mechanism, and then the discharge mechanism rotates forward to discharge the entire paper.

[0004] After printing, the paper ejection mechanism often lands on the paper tray. However, as paper accumulates on the tray and static electricity builds up between the sheets after printing, when double-sided printing is performed, the paper on the eject tray and the paper being ejected can be attracted and pulled into the printer due to static electricity, causing a paper jam. To address this issue, some printers incorporate a dual paper path in the ejection section. This adds an additional paper path, separating the ejection path from the return path. This increases the printer's complexity and cost, hindering printer miniaturization. Utility Model Content

[0005] The image forming device of the present invention can effectively solve the problem in the prior art that the paper discharge structure of the printer needs to be optimized.

[0006] According to one aspect of the present invention, there is provided an image forming apparatus, comprising:

[0007] An imaging unit, for generating an image on a medium;

[0008] a discharge mechanism for discharging the medium with the image;

[0009] a carrying unit for collecting and stacking the discharged medium discharged from the discharge mechanism;

[0010] Wherein, the discharge mechanism includes:

[0011] a discharge roller, for clamping and conveying the medium;

[0012] When the discharge roller rotates forward, the medium is discharged in a first direction; when the medium needs to be turned over, the discharge roller rotates in reverse to make the medium return in a second direction and re-enter the image forming device;

[0013] an intercepting member movably disposed in the discharge mechanism and capable of receiving power from the medium, the intercepting member comprising an intercepting portion and a triggering portion connected to each other;

[0014] The intercepting portion is used to prevent the discharged medium from entering the discharge mechanism, and the triggering portion is used to transmit a driving force to the intercepting portion;

[0015] In the first direction, the triggering portion is located at the upstream side of the intercepting portion.

[0016] In some embodiments, the blocking member may have a switchable blocking state and a conducting state;

[0017] When the medium is discharged in a first direction, the intercepting component is in a conducting state, and the medium passes through the intercepting portion; when the medium retreats in a second direction, the intercepting component is in an intercepting state, and the intercepting portion can block the discharged medium from entering the discharge mechanism.

[0018] In some embodiments, the intercepting portion rotates around a first axis, and the triggering portion rotates around a second axis, and the first axis and the second axis are parallel to an axis of the discharge roller.

[0019] In some embodiments, when the discharge roller drives the medium to be discharged in the first direction and returned in the second direction, the medium abuts against the trigger portion to generate power to drive the trigger portion to rotate, so that the trigger portion drives the intercepting portion to rotate.

[0020] In some embodiments, when the medium drives the trigger portion to rotate, the trigger portion drives the intercepting portion to rotate in the same direction.

[0021] In some embodiments, when the medium is discharged in the first direction and returned in the second direction, the rotation direction of the discharge roller is opposite to the rotation direction of the triggering portion and the intercepting portion.

[0022] In some embodiments, the intercepting member further includes a driven connecting rod, both ends of which are respectively connected to the triggering portion and the intercepting portion, and when the triggering portion rotates, the intercepting portion is driven to rotate via the driven connecting rod.

[0023] In some embodiments, the driven connecting rod is rotatably connected to the trigger portion and the intercepting portion, and the trigger portion drives the driven connecting rod to move when it rotates.

[0024] In some embodiments, the moving direction of the medium is opposite to the moving direction of the driven link.

[0025] In some embodiments, the intercepting portion has a pawl. When the medium is discharged along a first direction, the intercepting portion drives the pawl away from the medium. When the medium is retracted along a second direction, the intercepting portion drives the pawl close to the medium.

[0026] In some embodiments, the discharge mechanism is provided with a slide groove, the intercepting portion is slidably disposed in the slide groove, the trigger portion is rotatably disposed in the discharge mechanism, and the medium drives the trigger portion to rotate to drive the intercepting portion to slide along the slide groove.

[0027] In some embodiments, the image forming device includes a printing device and an automatic document feeder, and the ejection mechanism and the interception member are disposed in the printing device and / or the automatic document feeder. Thus, the interception mechanism can be disposed not only in the printing device but also in the automatic document feeder.

[0028] Compared with the prior art, the image forming device of the present invention has the following beneficial effects:

[0029] The present application drives the printing medium operation and discharges the printing medium through the discharge mechanism, and blocks and intercepts the discharged printing medium through the intercepting member. Since the printing medium has different movement directions when discharged during single-sided operation and when returned during double-sided operation, the triggering member can drive the intercepting member to move after receiving the power of the medium. The intercepting member can block the adsorbed discharged medium when the double-sided operation is returned, and prevent paper jams caused by the adsorption of excess paper when the paper is returned. The intercepting member does not require a special driving device, the cost is low, and there is no need to set up an additional paper path, which is conducive to the miniaturization of the machine body. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of the image forming device of the present invention;

[0031] Figure 2 This is a schematic diagram of the intercepting member and the discharge mechanism of the present invention installed in the image forming device;

[0032] Figure 3 for Figure 2 The schematic diagram of the structure after the fixing mechanism is omitted;

[0033] Figure 4 This is a reference diagram of the present invention when the intercepting member is not subjected to paper pressure;

[0034] Figure 5 This is a reference diagram for printing on one side of paper in the present invention;

[0035] Figure 6 This is a reference diagram for double-sided printing of paper in the present invention;

[0036] Figure 7 This is a simplified reference diagram of the intercepting member used when printing on both sides of paper in the present invention;

[0037] Figure 8 This is a reference diagram of the second embodiment of the intercepting member in the present invention;

[0038] Figure 9 This is a reference diagram of the third embodiment of the intercepting member in the present invention.

[0039] In the figure: 10-image forming device, 13-heating roller, 14-fixing pressure roller, 2-printing device, 21-print paper discharge tray, 22-discharge roller, 23-paper discharge guide wheel, 24-first support shaft, 25-second support shaft, 26-slide, 3-interceptor, 31-intercepting part, 311-ratchet, 312-first transmission part, 32-trigger part, 321-force-bearing part, 322-second transmission part, 33-driven connecting rod, 29-discharge guide part, paper-a, discharged paper-b. DETAILED DESCRIPTION

[0040] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0041] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this utility model, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0042] The utility model relates to an image forming device, such as a printer, a copier, a fax machine and an integrated printer, copier and fax machine, etc., which can form an image on a medium, and the medium is a carrier such as paper (original), sheet material, etc., which can display an image on the surface. The discharged medium is the discharged paper, such as the paper discharged to the paper discharge tray in the printer after printing.

[0043] In the following description, paper a represents “paper that has not been discharged to the paper discharge tray,” and paper b represents “paper that has been discharged to the paper discharge tray.”

[0044] The present invention will be further described in detail below with reference to the accompanying drawings.

[0045] Figure 1 The image forming apparatus 10 according to one embodiment of the present invention is schematically shown. Figure 1 As shown, the image forming apparatus 10 includes an automatic document feeding device and a printing device 2 .

[0046] Taking an automatic document feeding device with an automatic duplex scanning function of an ADF (Auto Document Feeder) as an example, the automatic document feeding device includes a scanning housing, a scanning paper feed tray, a scanning paper discharge tray, a scanning module and a paper feeding module. The scanning paper feed tray is installed in the scanning housing and is used to carry paper. The scanning module is installed in the scanning housing. The scanning module includes an image reader and a transmission component. The image reader can be a contact image sensor, and the image reader is installed on the transmission component. The paper feeding module is installed in the scanning housing. The paper feeding module is used to drive the paper through the scanning module to complete the scanning path for scanning in sequence, and complete the arrangement path for paper arrangement. The paper after scanning is discharged and collected on the scanning paper discharge tray.

[0047] like Figure 1-Figure 3 As shown, the printing device 2 includes a printing housing and a frame disposed within the housing. Various functional modules are mounted on the frame. The frame also includes a paper storage unit located at the bottom of the frame for storing paper to be printed, an imaging unit (transfer unit) located in the middle of the frame for forming an image on the paper, and an ejection mechanism located at the top of the frame for ejecting the paper. A conveying channel for conveying paper is formed within the frame. A paper pickup mechanism located above the paper storage unit removes paper from the paper storage unit and then conveys it to the imaging unit via the conveying channel. After the image is formed in the imaging unit, the paper is conveyed to the fixing unit. The fixing unit includes a heating roller 13 and a fixing pressure roller 14. The paper is pressurized between the heating roller 13 and the fixing pressure roller 14. The fixing mechanism fixes the image on the paper through high pressure and high heat. After being processed by the fixing mechanism, the paper is conveyed to the ejection mechanism, which ejects the paper onto a print paper tray 21 (i.e., a carrier unit). An operator can remove paper b from the print paper tray 21.

[0048] Among them, such as Figure 2 、 Figure 3 、 Figure 5As shown, the discharge mechanism includes a discharge roller 22 and a paper discharge guide wheel 23. Paper a can be discharged between the discharge roller 22 and the paper discharge guide wheel 23. The discharge roller 22 can actively move to drive the paper discharge guide wheel 23 to passively move. The discharge roller 22 can rotate forward and reverse to drive the paper a to be discharged along a first direction, and drive the paper a to be returned along a second direction for double-sided printing. The first direction (leftward direction) and the second direction (rightward) have different directions. When the discharge roller 22 rotates forward (clockwise), the paper a can be discharged along the first direction; when the paper a needs to be flipped, the discharge roller 22 reverses (counterclockwise) to make the paper a return along the second direction and re-enter the image forming device 10. The discharge roller 22 and the paper discharge guide wheel 23 are respectively located on the upper and lower sides of the paper a. Specifically, taking the printing process as an example, when performing single-sided printing, a blank paper a is transported from the paper storage unit to the transfer unit, so that the image is transferred to the paper a, and the paper a with the image enters the fixing unit, so that the image is fixed to the paper a after heating to complete the first side printing, and then the discharge guide component 29 is pushed open and output from the discharge roller 22 to the outside of the machine as the first path (when only single-sided printing is required, the paper a is directly output from the discharge roller 22 along the first direction, and at this time the discharge roller 22 rotates in the positive direction). During duplex printing, that is, after completing single-sided printing, the paper a is not output from the discharge roller 22 until the end of the paper a reaches the discharge roller 22. At this time, the discharge roller 22 rotates in the opposite direction to drive the paper a that has completed single-sided printing to return along the second direction, that is, to send the paper a back. Because it is intercepted by the discharge guide component 29, the paper a will not re-enter the fixing unit but will enter the second path. After passing through the second path, it can re-enter the first path, so that the paper a achieves the effect of "turning over". When re-entering the first path, the paper a completes the second side printing after the transfer and fixing operations on the second side. Then the paper a pushes the discharge guide component 29 open and is finally driven from the discharge roller 22 to be output to the print paper discharge tray 21.

[0049] A sensor is also provided at the discharge guide component 29 to detect whether there is paper in the current path to determine whether a paper jam has occurred.

[0050] In order to avoid the problem of paper a being sucked into the ejected paper b stacked on the print paper ejection tray 21 when returning along the second direction during double-sided printing, and entering the ejection mechanism to cause paper jam, the image forming device 10 also includes an interceptor 3. In this embodiment, taking the printing device 2 as an example, the interceptor 3 is arranged in the ejection mechanism. The interceptor 3 is used to block the paper b on the print paper ejection tray 21 from entering the ejection mechanism when the paper a moves along the second direction. During single-sided printing (paper a travels along the first path), the normal operation and output of the paper a is not affected. Therefore, the interceptor 3 has two states, namely, an on state and an intercepting state. The on state is the situation where the interceptor 3 has not been triggered to intercept, and the intercepting state is the situation where the interceptor 3 has been triggered to intercept. The triggering situation of the interceptor 3 is mainly related to the movement direction of the paper a, and no other driving structure is required.

[0051] Specifically, such as Figure 3 As shown, the intercepting member 3 includes an intercepting portion 31 and a triggering portion 32, which adopt a combined structure. The intercepting portion 31 is in the shape of a strip-shaped hook claw, and is provided with multiple pieces and arranged along the axial direction of the discharge roller 22. The intercepting portion 31 is rotatably arranged in the discharge mechanism to block the paper b on the print paper discharge tray 21. The intercepting portion 31 has a pawl 311 and a first transmission portion 312. The pawl 311 is bent and the first transmission portion 312 is integrally formed with the pawl 311. A curved angle or arc structure is formed between the first transmission portion 312 and the pawl 311 to facilitate rotation under force. Preferably, the first transmission portion 312 and the pawl 311 form a right angle structure. The discharge mechanism is provided with a first support shaft 24 for supporting and limiting the rotation fulcrum of the intercepting portion 31. The first support shaft 24 is located at the connection between the pawl 311 and the first transmission portion 312 in the intercepting portion 31. Through the shaft hole structure, the intercepting portion 31 can rotate about the first support shaft 24. The axis of the intercepting portion 31 is parallel to the axis of the discharge roller 22. The first transmission part 312 is in transmission connection with the trigger part 32 , and specifically can be hingedly connected via a shaft hole structure. The trigger part 32 can abut against the paper a to move under force.

[0052] In this embodiment, Figure 3As shown, the intercepting member 3 further includes a driven link 33, the ends of which are rotatably connected to the trigger portion 32 and the first transmission portion 312, respectively. The trigger portion 32 can abut against the paper a to receive force and move. To facilitate the force-receiving movement of the trigger portion 32, the trigger portion 32 includes a force-receiving portion 321 and a second transmission portion 322. The force-receiving portion 321 and the second transmission portion 322 are integrally formed. The force-receiving portion 321 can abut against the paper a to receive force, thereby receiving the force of the paper a. The second transmission portion 322 is rotatably connected to the driven link 33. A second support shaft 25 is provided between the force-receiving portion 321 and the second transmission portion 322. The discharge mechanism is provided with a hole that can mate with the second support shaft 25. The trigger portion 32 is rotatably mounted on the discharge mechanism through the hole-shaft engagement. The second support shaft 25 serves as the rotation fulcrum of the trigger portion 32, and the rotation axis of the trigger portion 32 is parallel to the axis of the discharge roller 22. When the triggering portion 32 is rotated by force, the driving force can be transmitted to the intercepting portion 31 through the driven connecting rod 33, so that the intercepting portion 31 rotates. In the first direction, the triggering portion is located on the upstream side of the intercepting portion.

[0053] Working principle: Figure 4 As shown in FIG, when the trigger portion 32 is not pressed by the paper a and is in a free state, the force-bearing portion 321 faces upward. Figure 5 As shown, when paper a is only printed on one side, the discharge roller 22 drives the paper a to move along the first direction to discharge the paper a. During this process, the paper a continuously contacts the trigger portion 32, causing the trigger portion 32 to rotate counterclockwise under the pressure of the paper a. The force-bearing portion 321 receives the driving force in the first direction, which drives the driven link 33 to have a rightward trend, so that the first transmission portion 312 has a component force pulling to the right. Therefore, the intercepting portion 31 has a counterclockwise rotation trend, and the pawl 311 is in a state of being away from the paper a. This state is the conducting state of the intercepting member 3; as shown in FIG. Figure 6 、 Figure 7 As shown, when paper a needs to be printed on both sides, after passing through the first path (i.e., after single-sided printing is completed), the discharge roller 22 drives paper a back in the opposite direction. At this point, paper a moves in the second direction, abutting the trigger portion 32, causing it to rotate clockwise. The force-bearing portion 321 receives a component of force in the second direction, driving the trigger portion 32 to rotate clockwise and pushing the driven link 33 to the left, driving the intercepting portion 31 to rotate clockwise. The pawl 311 approaches one side of paper a, blocking paper b. This state is the intercepting state of the intercepting member 3. After completing double-sided printing, paper a is discharged in the first direction. Paper a applies force to the force-bearing portion 321, causing the trigger portion 32 to gradually rotate counterclockwise. Similar to the single-sided printing operation for paper a, the intercepting mechanism 3 returns to the on state until paper a is discharged.

[0054] Of course, this embodiment can also be applied to an automatic document feeding device, which can perform single-sided scanning and double-sided scanning when scanning paper a. Similar to the printing device 2, the intercepting mechanism 3 of this embodiment can also be set in the paper discharge structure of the automatic document feeding device to avoid paper jams during double-sided scanning.

[0055] It can be seen that this solution can intercept the paper b that is adsorbed when double-sided printing is retracted, avoiding the paper jam problem caused by the adsorption of paper b stacked on the paper output tray when paper a is retracted, so as to improve the user experience. The intercepting part 3 is linked with the movement posture of paper a, and no special driving device is required, which is low in cost. Compared with the existing technology, this solution has a simpler structure and does not require an additional paper path, which is conducive to the miniaturization of the machine body.

[0056] In some embodiments, as Figure 8 As shown, the trigger part 32 adopts a single component structure to directly drive the trigger part 32 to rotate. The trigger part 32 is rotatably connected to the intercepting part 31. Similar to the above embodiment, the trigger part 32 and the driven connecting rod 33 are integrally formed, that is, the second transmission part 322 is extended so that the trigger part 32 has a bent shape to facilitate force movement. The size between the rotation center of the trigger part 32 and the rotation center of the intercepting part 31 can be appropriately changed to facilitate force driving, or the size of the first transmission part 312 can be extended to lengthen the force arm of the intercepting part 31 rotation, so that the intercepting part 31 is easier to rotate under force. The working principle of the intercepting mechanism 3 is similar to that described above and will not be repeated. This embodiment is conducive to saving the manufacturing process of the trigger part 32 and saving costs. At the same time, the trigger part 32 and the intercepting part 31 cooperate to transmit the rotational force more smoothly, which is conducive to the flexibility of the intercepting part 31 rotation.

[0057] In some embodiments, as Figure 9As shown, another embodiment of the intercepting member 3 is provided. In this embodiment, the intercepting member 31 adopts a sliding structure, and the triggering member 32 adopts a rotating structure. The driving force of the triggering member 32 drives the intercepting member 31 to slide and intercept the paper b. Specifically, the discharge mechanism includes a chute 26, and the intercepting member 31 is slidably disposed within the chute 26. The chute 26 is used to guide the movement direction of the intercepting member 31. To facilitate the transmission of driving force by the triggering member 32, a driven link 33 is rotatably connected between the intercepting member 31 and the triggering member 32, similar to the above embodiment. When the paper a moves in a first direction, the triggering member 32 is pressed and can rotate counterclockwise, driving the driven link 33 to move downward. This further causes the driven link 33 to drive the intercepting member 31 downward along the chute 26, placing the intercepting member 3 in a conductive state. When paper a is returned along the second direction, the trigger portion 32 is pressured and can rotate clockwise to drive the driven link 33 to have an upward movement component, and further the driven link 33 drives the intercepting portion 31 to move upward along the slide groove 26, so that the intercepting member 3 is in an intercepting state, and the intercepting portion 31 can block paper b. This embodiment provides a variety of implementation methods of the intercepting member 3, which is conducive to miniaturization.

[0058] The above description is only a preferred embodiment of the present invention. To keep the description concise, not all possible combinations of the various technical features in the above embodiment are described. This does not limit the present invention in any form. Therefore, any modifications, equivalent changes and modifications made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An image forming apparatus, comprising: An imaging unit, for generating an image on a medium; a discharge mechanism for discharging the medium with the image; a carrying unit for collecting and stacking the discharged medium discharged from the discharge mechanism; Wherein, the discharge mechanism includes: a discharge roller, for clamping and conveying the medium; When the discharge roller rotates forward, the medium is discharged in a first direction; when the medium needs to be turned over, the discharge roller rotates in reverse to make the medium return in a second direction and re-enter the image forming device; an intercepting member movably disposed in the discharge mechanism and capable of receiving power from the medium, the intercepting member comprising an intercepting portion and a triggering portion connected to each other; The intercepting portion is used to prevent the discharged medium from entering the discharge mechanism, and the triggering portion is used to transmit a driving force to the intercepting portion; Wherein, in the first direction, the triggering portion is located on the upstream side of the intercepting portion.

2. The image forming apparatus according to claim 1, wherein The intercepting member has a switchable intercepting state and a conducting state; When the medium is discharged in the first direction, the intercepting member is in a conducting state, and the medium passes through the intercepting portion; When the medium retreats along the second direction, the intercepting member is in an intercepting state, and the intercepting portion blocks the discharged medium from entering the discharge mechanism.

3. The image forming apparatus according to claim 1, wherein The intercepting portion rotates around a first axis, and the triggering portion rotates around a second axis, and the first axis and the second axis are parallel to an axis of the discharge roller.

4. The image forming apparatus according to claim 3, wherein When the discharge roller drives the medium to be discharged in the first direction and returned in the second direction, the medium abuts against the trigger portion to generate power to drive the trigger portion to rotate, so that the trigger portion drives the intercepting portion to rotate.

5. The image forming apparatus according to claim 4, wherein: When the medium drives the triggering portion to rotate, the triggering portion drives the intercepting portion to rotate in the same direction.

6. The image forming apparatus according to claim 3, wherein When the medium is discharged in the first direction and returned in the second direction, the rotation direction of the discharge roller is opposite to the rotation direction of the triggering portion and the intercepting portion.

7. The image forming apparatus according to claim 3, wherein The intercepting member further includes a driven connecting rod, both ends of which are connected to the triggering portion and the intercepting portion respectively. When the triggering portion rotates, the intercepting portion is driven to rotate via the driven connecting rod.

8. The image forming apparatus according to claim 7, wherein: The driven connecting rod is rotatably connected to the trigger portion and the intercepting portion, and the trigger portion drives the driven connecting rod to move when it rotates.

9. The image forming apparatus according to claim 7, wherein The moving direction of the medium is opposite to the moving direction of the driven connecting rod.

10. The image forming apparatus according to claim 1, wherein The intercepting portion has a ratchet. When the medium is discharged along a first direction, the intercepting portion drives the ratchet away from the medium. When the medium is retracted along a second direction, the intercepting portion drives the ratchet toward the medium.

11. The image forming apparatus according to claim 1, wherein The discharge mechanism is provided with a slide groove, the intercepting portion is slidably arranged in the slide groove, the triggering portion is rotatably arranged in the discharge mechanism, and the medium drives the triggering portion to rotate to drive the intercepting portion to slide along the slide groove.

12. The image forming apparatus according to any one of claims 1 to 11, wherein: The image forming apparatus includes a printing device and an automatic document feeding device, and the ejection mechanism and the intercepting member are provided in the printing device and / or the automatic document feeding device.