A collapse prevention device

Abstract

This invention discloses an anti-coil-collapse device, relating to the field of steel coil uncoiling technology. It is used to limit the axial displacement of a steel coil during the uncoiling process after it has been loaded onto an uncoiling device. The uncoiling device includes an uncoiling roller mounted on the machine body. The uncoiling roller carries the steel coil and is rotatable for uncoiling. The anti-coil-collapse device includes: a first limiting unit disposed at the first end of the uncoiling roller to prevent the steel coil from shifting towards the first end of the uncoiling roller; and a second limiting unit disposed at the second end of the uncoiling roller, the second limiting unit including a second limiting disc and a second adjusting part for driving the second limiting disc to switch between a first state and a second state. This invention ensures that the limiting disc rotates synchronously with the uncoiling roller and can also synchronously adjust the axial position of the limiting disc during rotation. It uses the same axial driving component as the uncoiling device, and a single axial displacement is sufficient to complete the axial adaptation of the steel coil.

Description

Technical Field

[0001] This invention relates to the field of steel coil unwinding technology, specifically to an anti-coil-collapse device. Background Technology

[0002] As the supporting foundation of the steel coil, the unwinding roll is prone to shifting and collapsing along the axial direction of the unwinding roll during the unwinding process, causing the unwound steel strip to deviate axially. Therefore, anti-collapse devices need to be installed at both ends of the unwinding roll to prevent the steel coil from collapsing axially.

[0003] Existing anti-coil-collapse devices typically have a fixed limiter at the non-loading end of the unwinding roller and a movable avoidance limiter at the loading end to accommodate both loading / unloading operations and unwinding limits. However, to ensure that the movable end limiter rotates synchronously with the unwinding roller, its docking position with the unwinding roller is often fixed and cannot be adjusted. For steel coils of different widths, an additional independent width adjustment drive mechanism must be added to perform an axial adjustment action separately after the steel coil is loaded. This not only leads to a complex overall structure, a large number of parts, and high manufacturing costs, but also increases the number of coil changing steps and reduces production efficiency. At the same time, the control logic of the two independent drive mechanisms is independent of each other, making debugging and maintenance difficult, and occupying more space, which is not conducive to the compact design of the equipment. Summary of the Invention

[0004] The purpose of this invention is to provide an anti-collapse device to address the shortcomings of the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an anti-coil-collapse device for limiting the axial displacement of a steel coil during the uncoiling process after the coil is loaded onto an uncoiling device, wherein the uncoiling device includes an uncoiling roller mounted on the machine body, the uncoiling roller being used to carry the steel coil and rotatable to achieve uncoiling, a first end of the uncoiling roller being drively connected to an uncoiling drive mechanism, and a second end being cantilevered; the anti-coil-collapse device includes: A first limiting unit is disposed at the first end of the unwinding roller to prevent the steel coil from shifting toward the first end of the unwinding roller; The second limiting unit is disposed at the second end of the unwinding roller. The second limiting unit includes a second limiting disk and a second adjusting part for driving the second limiting disk to switch between a first state and a second state. In the first state, the second adjustment unit drives the second limiting disc to disengage from the unwinding roller to avoid creating operating space for loading and unloading steel coils; In the second state, the second adjustment unit drives the second limiting disk to be arranged coaxially with the unwinding roller and rotate synchronously to prevent the steel coil from shifting towards the second end of the unwinding roller, and the second adjustment unit can drive the second limiting disk to move along the axial direction of the unwinding roller to adjust the distance between the first limiting unit and the second limiting unit.

[0006] Preferably, the first limiting unit includes a first limiting disk and a first adjusting part. The first limiting disk is coaxially arranged with the unwinding roller and can rotate synchronously with the unwinding roller. The first adjusting part is configured to adjust the position of the first limiting disk along the axial direction of the unwinding roller.

[0007] Preferably, the first adjusting part includes a hydraulic cylinder and a circumferential transmission component. The circumferential transmission component is configured to transmit the rotational power of the unwinding roller to the first limiting plate, and cooperate with the hydraulic cylinder to realize the axial displacement of the first limiting plate along the unwinding roller.

[0008] Preferably, the circumferential transmission component includes an inner nest, an axial sliding sleeve, and a mounting plate. The inner nest is fixedly sleeved on the unwinding roller. The axial sliding sleeve is configured to rotate synchronously with the inner nest and to be displaced axially along the inner nest. The mounting plate is rotatably connected to the outside of the axial sliding sleeve via a bearing. The first limiting plate is fixedly installed at the end of the axial sliding sleeve. The telescopic end of the hydraulic cylinder is fixedly connected to the mounting plate.

[0009] Preferably, the second adjustment part includes a switching component and a connecting component. The movable end of the switching component is rotatably connected to the second limiting disk through the connecting component. The switching component is used to drive the second limiting disk to switch between a first state and a second state.

[0010] Preferably, the switching component includes a first telescopic member arranged in the same direction as the unwinding roller and a swing arm hinged to the movable end of the first telescopic member. The end of the swing arm away from the hinge point is connected to the connecting component. The swing arm is driven to swing by a second telescopic member to move the connecting component and the second limiting plate away from the unwinding roller to achieve positioning.

[0011] Preferably, the connecting assembly includes a connecting shaft and a transmission part, the transmission part being configured to transmit the rotational power of the connecting shaft to the second limiting disk and to allow the second limiting disk to slide along the axial direction of the connecting shaft.

[0012] Preferably, the transmission part includes a roller conveyor, a fixed sleeve, a rotating sleeve, and a roller shaft rotatably connected to the rotating sleeve on the connecting shaft. The fixed sleeve is fixedly installed in the second adjustment part, and the rotating sleeve is rotatably assembled in the fixed sleeve through a bearing. One end of the rotating sleeve is fixedly connected to the second limiting plate.

[0013] Preferably, at least one roller conveyor is provided on the connecting shaft, and in the second state, the roller shaft rolls within the roller conveyor.

[0014] Preferably, the feed end of the roller conveyor is provided with a guide structure, the opening width of which gradually increases along the entry direction of the roller shaft to guide the roller shaft into the roller conveyor.

[0015] The anti-collapse device provided by the present invention, as described above, has the following beneficial effects: 1. The integrated rotary transmission structure ensures that the limiting disc rotates synchronously with the unwinding roller, and also allows for synchronous adjustment of the axial position of the second limiting disc during rotation. The drive shares the same axial drive component as the unwinding roller, and the axial adaptation of the steel coil can be completed with a single axial displacement.

[0016] 2. The first and second limiting units form axial constraints from both sides of the steel coil. Both limiting discs can be independently adjusted along the axial direction of the unwinding roller to adapt to steel coils of different widths and specifications. This eliminates the centering deviation caused by the fixed limiting on one side, and achieves anti-collapse during unwinding and centering during steel coil loading. It also prevents the position of the steel strip after unwinding from exceeding the adjustment limit of the downstream correction equipment, thus reducing the correction burden of subsequent processes. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 This is a schematic diagram of the anti-collapse roll device of the present invention in the first state; Figure 2 This is a schematic diagram of an anti-collapse device of the present invention when the second limiting plate and the unwinding roller are coaxial; Figure 3 This is a schematic diagram of the structure of the anti-collapse roll device of the present invention in the second state; Figure 4 This is a partial cross-sectional view of an anti-collapse roll device according to the present invention; Figure 5 This invention provides an attachment to an anti-collapse roll device. Figure 4 Enlarged view of point A in the middle; Figure 6 This is a cross-sectional view of the transmission part of an anti-collapse winding device according to the present invention.

[0019] Explanation of reference numerals in the attached drawings: 1. Unwinding device; 2. Unwinding roller; 3. First limiting unit; 4. Second limiting unit; 5. Connecting shaft; 6. Second limiting plate; 31. Hydraulic cylinder; 32. Inner nest; 33. Flat key; 34. Axial sliding sleeve; 341. Axial keyway; 35. Mounting plate; 36. First limiting plate; 41. First telescopic component; 43. Swing arm; 44. Second telescopic component; 45. Fixed sleeve; 47. Rotating sleeve; 48. Roller shaft; 51. Roller conveyor. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0021] Please see Figure 1-6 This invention provides an anti-coil-collapse device for limiting the axial displacement of a steel coil during the uncoiling process after it is loaded onto an uncoiling device 1. The uncoiling device 1 includes an uncoiling roller 2 mounted on the machine body. The uncoiling roller 2 carries the steel coil and is rotatable for uncoiling. A first end of the uncoiling roller 2 is connected to an uncoiling drive mechanism, and a second end is suspended. The anti-coil-collapse device includes: The first limiting unit 3 is disposed at the first end of the unwinding roller 2 to prevent the steel coil from shifting toward the first end of the unwinding roller; The second limiting unit 4 is disposed at the second end of the unwinding roller 2. The second limiting unit 4 includes a second limiting disk 6 and a second adjustment part for driving the second limiting disk 6 to switch between a first state and a second state. In the first state, the second adjustment unit drives the second limiting disk 6 to disengage from the unwinding roller 2 to avoid creating operating space for loading and unloading steel coils; In the second state, the second adjustment unit drives the second limiting disk 6 to be arranged coaxially with the unwinding roller 2 and rotate synchronously to prevent the steel coil from shifting to the second end of the unwinding roller 2. The second adjustment unit can also drive the second limiting disk 6 to move along the axial direction of the unwinding roller 2 to adjust the distance between the first limiting unit 3 and the second limiting unit 4.

[0022] Specifically, in this embodiment, a second limiting unit 4 is provided on one side of the machine body. In the first state, the second adjusting unit controls the second limiting disk 6 to be completely disengaged from the axis of the unwinding roller 2, thereby avoiding the operating space required for loading and unloading the steel coil, so that the steel coil can be smoothly mounted onto the unwinding roller 2 from the loading end, or unloaded from the unwinding roller 2. In the second state, the second adjusting unit controls the second limiting disk 6 to be coaxially connected with the unwinding roller 2 and rotate synchronously, so that the second limiting disk 6 can rotate together with the unwinding roller 2. During the synchronous rotation of the second limiting disk 6 with the unwinding roller 2, the second adjusting unit can still adjust the position of the second limiting disk 6 along the axial direction of the unwinding roller 2. That is, the axial position of the second limiting disk 6 can be dynamically adjusted during the unwinding process, so as to adapt to steel coils of different widths or achieve real-time centering and correction without stopping the machine.

[0023] In this embodiment, the same axial drive source is used as both the axial power source for state switching and the width adjustment power source in the working state. Compared with the prior art, which sets the avoidance drive and the width adjustment drive separately, this embodiment combines the two independent mechanisms into one, eliminating the need for a separate width adjustment drive mechanism, reducing manufacturing costs and assembly difficulty, and saving installation space. Furthermore, since the second limiting plate 6 can still be axially adjusted in synchronous rotation, the axial position of the second limiting plate 6 can be finely adjusted in real time according to the actual position of the steel coil during the unwinding process, so as to realize the dynamic centering and correction of the steel coil, avoid the strip deviation caused by the initial set deviation of the steel coil or the gradual offset during the unwinding process, reduce the adjustment burden of the downstream correction equipment, and prevent the strip position from exceeding the correction limit.

[0024] As a preferred embodiment, the first limiting unit 3 includes a first limiting disk 36 and a first adjusting part. The first limiting disk 36 is coaxially arranged with the unwinding roller 2 and can rotate synchronously with the unwinding roller 2. The first adjusting part is configured to adjust the position of the first limiting disk 36 along the axial direction of the unwinding roller 2. The first adjusting part includes a hydraulic cylinder 31 and a circumferential transmission component. The circumferential transmission component is configured to transmit the rotational power of the unwinding roller 2 to the first limiting disk 36 and cooperate with the hydraulic cylinder 31 to realize the axial displacement of the first limiting disk 36 along the unwinding roller. The circumferential transmission component includes an inner nest 32, an axial sliding sleeve 34, and a mounting disk 35. The inner nest 32 is fixedly sleeved on the unwinding roller 2. The axial sliding sleeve 34 is configured to rotate synchronously with the inner nest 32 and can be displaced along the axial direction of the inner nest 32. The mounting disk 35 is rotatably connected to the outside of the axial sliding sleeve 34 through a bearing. The first limiting disk 36 is fixedly installed on the end of the axial sliding sleeve 34. The telescopic end of the hydraulic cylinder 31 is fixedly connected to the mounting disk 35.

[0025] Specifically, the hydraulic cylinder 31 outputs linear thrust as an axial drive source, which can drive the first limiting plate 36 to complete the axial position adjustment. The circumferential transmission component is the carrier for transmitting the rotational motion. One part rotates synchronously with the unwinding roller 2, and the other part is circumferentially fixed with the first limiting plate 36. It transmits the rotation of the unwinding roller 2 to the first limiting plate 36, while retaining the axial sliding degree of freedom, so that the first limiting plate 36 can rotate circumferentially with the unwinding roller 2 and can also move freely in the axial direction. As a preferred technical solution in this embodiment, the rotational motion between the first limiting disk 36 and the stationary oil cylinder 31 is decoupled. The oil cylinder 31, as a stationary component, does not need to rotate with the unwinding roller 2. While ensuring high coaxiality of the overall structure, the amount of sway during rotation is minimized, ensuring good fit of the end face of the first limiting disk 36. Under the premise of ensuring axial adjustment function, the driving stability is improved. To achieve the above functions, an axial keyway 341 is opened on the inner wall of the axial sliding sleeve 34, and a flat key 33 is correspondingly set in the inner nest 32. The circumferential transmission and axial sliding are realized through the cooperation of the flat key.

[0026] As a preferred technical solution of this embodiment, the second adjustment part includes a switching component and a connecting component. The movable end of the switching component is rotatably connected to the second limiting disk 6 through the connecting component. The switching component is used to drive the second limiting disk 6 to switch between the first state and the second state.

[0027] Specifically, the switching component acts as the power actuator for state switching, outputting a large-stroke displacement or a small-stroke displacement, driving the connecting component and the second limit plate 6 to complete the position switching between the working position and the avoidance position, as well as the dynamic fine adjustment of the second limit plate 6 during the rotation of the unwinding roller 2. The connecting component acts as the intermediate carrier connecting part, with one end connected to the movable end of the switching component and the other end assembled with the second limit plate 6 by rotation. It not only transmits the positional relationship of the switching, but also allows the second limit plate 6 to rotate freely around its own axis, so as to realize the synchronous rotation of the second limit plate 6 with the steel coil. By separating the state switching and rotation limit functions, the switching component is responsible for large displacement avoidance and fine adjustment, while the connecting component is responsible for rotation. After separation, the functions are independent, which facilitates assembly and debugging. Moreover, the rotation connection structure ensures that the second limit plate 6 can rotate with the steel coil without resistance, without creating rotational resistance to the unwinding of the steel coil, thus ensuring more stable unwinding tension.

[0028] As a preferred technical solution in this embodiment, the axial driving member is a first telescopic member 41 arranged in the same direction as the unwinding roller 2. The movable end of the first telescopic member 41 is hinged to a swing arm 43. The end of the swing arm 43 away from the hinge point is connected to the connecting component. The swing arm 43 is driven to swing by the second telescopic member 44 so as to drive the connecting component and the second limiting plate 6 away from the unwinding roller 2 to achieve avoidance.

[0029] Specifically, the first telescopic component 41 is arranged along the axial direction of the unwinding roller 2 and is used to drive the axial feed and retraction of the second limiting plate 6 to achieve axial position adjustment and adaptation to the end face of the steel coil. The swing arm 43, as a steering transmission component, swings around the hinge point under the drive of the second telescopic component 44, converting the linear driving force of the second telescopic component 44 into the swing motion of the swing arm, causing the connecting component at the end and the second limiting plate 6 to swing laterally as a whole, separating them from the axial range of the unwinding roller 2, thus achieving material loading and unloading avoidance. In this way, the avoidance action can be completed with a shorter axial displacement combined with the lateral flipping of the swing arm 43. Compared with the traditional cantilevered translation structure, it greatly reduces the space occupied, and while meeting the large avoidance space requirement, it ensures the support rigidity and limit stability in the working state.

[0030] As a preferred technical solution of this embodiment, the connecting component includes a connecting shaft 5 and a transmission part. The transmission part is configured to transmit the rotational power of the connecting shaft 5 to the second limiting disk 6 and allow the second limiting disk 6 to slide along the axial direction of the connecting shaft 5.

[0031] Specifically, in the working state, the connecting shaft 5 is connected to the rotating sleeve 47. The transmission part, as the intermediate structure for torque transmission, synchronously transmits the rotational motion of the connecting shaft 5 to the second limiting disk 6, while retaining the degree of freedom for the second limiting disk 6 to move along the axial direction of the connecting shaft. This allows the second limiting disk to rotate synchronously with the connecting shaft, and the rotational motion of the second limiting disk 6 and the axial adjustment motion do not interfere with each other.

[0032] As a preferred technical solution of this embodiment, the transmission part further includes a roller conveyor 51, a fixed sleeve 45, a rotating sleeve 47, and a roller shaft 48 rotatably connected to the rotating sleeve 47, which is opened on the connecting shaft 5. The fixed sleeve 45 is fixedly installed on the second adjustment part, and the rotating sleeve 47 is rotatably assembled to the fixed sleeve 45 through a bearing. One end of the rotating sleeve 47 is fixedly connected to the second limiting plate 6.

[0033] Specifically, when the connecting shaft 5 rotates, the side wall of the roller conveyor 51 pushes against the roller shaft 48, thereby driving the rotating sleeve 47 and the second limiting disk 6 to rotate synchronously in the circumferential direction to ensure high-precision transmission. Furthermore, as the rotating sleeve 47 moves axially along the connecting shaft, the roller shaft 48 can roll along the roller conveyor 51, converting sliding friction into rolling friction and significantly reducing the resistance to axial movement. Compared to the conventional spline fit, which suffers from high axial resistance, easy wear, and large transmission clearance, this embodiment ensures the accuracy of circumferential synchronous transmission while significantly reducing the running resistance of axial adjustment, thereby improving the structural load-bearing rigidity and service life.

[0034] As a preferred technical solution of this embodiment, at least one roller track 51 is provided on the connecting shaft 5. In the second state, the roller shaft 48 rolls within the roller track 51.

[0035] Specifically, by setting up a roller conveyor 51 and a corresponding roller shaft 48, the precise transmission of the unwinding roller 2 and the second limiting plate 6 can be achieved. When the first telescopic member 41 drives the rotating sleeve 47 to move axially along the connecting shaft 5, the roller shaft 48 rolls forward axially along the roller conveyor 51. Rolling friction ensures smooth movement and high stability.

[0036] In another embodiment of the present invention, for uncoiling conditions of heavy-duty, wide steel coils, the radial load borne by the uncoiling roller 2 far exceeds that of conventional applications. Its single-end fixed cantilever support structure is prone to deflection at the distal end due to insufficient rigidity, causing problems such as uncoiling sway, strip deviation, and tension fluctuation. To address this, this solution sets the number of roller tracks 51 to four, and the corresponding number of roller shafts 48 to four. Each roller shaft 48 rolls within its corresponding roller track 51 to provide radial auxiliary support to the distal end of the uncoiling roller 2.

[0037] Specifically, the corresponding switching components are selected with telescopic components that have the ability to bear off-center loads. The four roller tracks are evenly distributed at 90° around the connecting shaft 5. The four roller shafts 48 are evenly distributed around the inner wall of the rotating sleeve 47, forming a four-point support system that is completely symmetrical in the upper and lower and left and right directions. When the far end of the unwinding roller 2 is subjected to the gravity of the steel coil and has a downward deflection tendency, the roller shaft 48 applies an upward support reaction force to the connecting shaft 5 through the roller track 51, which directly offsets part of the radial load. Since the connecting shaft 5 and the unwinding roller 2 are coaxial in the working state, the radial support obtained by the connecting shaft 5 can be directly transmitted to the cantilever end of the unwinding roller 2, which effectively extends the effective support span of the unwinding roller 2 and significantly strengthens its overall bending stiffness. In this scheme, the roller shaft 48 and roller conveyor 51 have a rolling fit structure, which simultaneously has the functions of circumferential torsion transmission, axial sliding and radial load bearing: its axial adjustment resistance is small, and it forms a stable multi-point support through four roller shafts evenly distributed in the circumference. It can be directly used as an auxiliary load bearing structure to strengthen the far end stiffness and accurately offset the deflection deformation of the unwinding roller 2. At the same time, the rolling fit structure has a higher tolerance for assembly errors.

[0038] As a preferred technical solution in this embodiment, the feed end of the roller conveyor 51 is provided with a guide structure. The opening width of the guide structure gradually increases along the entry direction of the roller shaft 48 to guide the roller shaft 48 into the roller conveyor 51.

[0039] Specifically, when the roller 48 enters the roller conveyor 51 axially from the end of the connecting shaft 5, even if there is a radial deviation between the roller 48 and the roller conveyor 51, the roller 48 can first contact the inclined surface of the guide structure. In this way, the inclined surface generates a radial component force on the roller 48 under the action of axial thrust, automatically correcting the radial position of the roller. After the roller 48 is guided, it smoothly enters the working section of the roller conveyor 51.

[0040] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An anti-collapse device, characterized in that, The device is used to limit the axial displacement of the steel coil during the unwinding process after it is loaded into the unwinding equipment (1). The unwinding equipment (1) includes an unwinding roller (2) mounted on the machine body. The unwinding roller (2) is used to carry the steel coil and can rotate to achieve unwinding. The first end of the unwinding roller (2) is connected to the unwinding drive mechanism, and the second end is suspended. The anti-collapse device includes: The first limiting unit (3) is disposed at the first end of the unwinding roller (2) to prevent the steel coil from shifting toward the first end of the unwinding roller; The second limiting unit (4) is disposed at the second end of the unwinding roller (2). The second limiting unit (4) includes a second limiting disk (6) and a second adjustment part for driving the second limiting disk (6) to switch between a first state and a second state. In the first state, the second adjustment unit drives the second limiting disk (6) to disengage from the unwinding roller (2) to avoid the operation space for loading and unloading steel coils; In the second state, the second adjustment unit drives the second limiting disk (6) to be arranged coaxially with the unwinding roller (2) and rotate synchronously to prevent the steel coil from shifting to the second end of the unwinding roller (2), and the second adjustment unit can drive the second limiting disk (6) to move along the axial direction of the unwinding roller (2) to adjust the distance between the first limiting unit (3) and the second limiting unit (4).

2. The anti-collapse device according to claim 1, characterized in that, The first limiting unit (3) includes a first limiting disk (36) and a first adjusting part. The first limiting disk (36) is coaxially arranged with the unwinding roller (2) and can rotate synchronously with the unwinding roller (2). The first adjusting part is configured to adjust the position of the first limiting disk (36) along the axial direction of the unwinding roller (2).

3. The anti-collapse device according to claim 2, characterized in that, The first adjustment unit includes a hydraulic cylinder (31) and a circumferential transmission component. The circumferential transmission component is configured to transmit the rotational power of the unwinding roller (2) to the first limiting plate (36) and cooperate with the hydraulic cylinder (31) to realize the axial displacement of the first limiting plate (36) along the unwinding roller (2).

4. The anti-collapse device according to claim 3, characterized in that, The circumferential transmission component includes an inner nest (32), an axial sliding sleeve (34), and a mounting plate (35). The inner nest (32) is fixedly sleeved on the unwinding roller (2). The axial sliding sleeve (34) is configured to rotate synchronously with the inner nest (32) and to be displaced along the axial direction of the inner nest (32). The mounting plate (35) is rotatably connected to the outside of the axial sliding sleeve (34) via a bearing. The first limiting plate (36) is fixedly installed at the end of the axial sliding sleeve (34). The telescopic end of the hydraulic cylinder (31) is fixedly connected to the mounting plate (35).

5. The anti-collapse device according to claim 1, characterized in that, The second adjustment unit includes a switching component and a connecting component. The movable end of the switching component is rotatably connected to the second limiting disk (6) through the connecting component. The switching component is used to drive the second limiting disk (6) to switch between a first state and a second state.

6. The anti-collapse device according to claim 5, characterized in that, The switching assembly includes a first telescopic member (41) arranged in the same direction as the unwinding roller (2) and a swing arm (43) hinged to the movable end of the first telescopic member (41). The end of the swing arm (43) away from the hinge point is connected to the connecting assembly. The swing arm (43) is driven to swing by the second telescopic member (44) to drive the connecting assembly and the second limiting plate (6) away from the unwinding roller (2) to achieve positioning.

7. The anti-collapse device according to claim 5, characterized in that, The connecting assembly includes a connecting shaft (5) and a transmission part, the transmission part being configured to transmit rotational power of the connecting shaft (5) to the second limiting disk (6) and to allow the second limiting disk (6) to slide axially along the connecting shaft (5).

8. The anti-collapse device according to claim 7, characterized in that, The transmission unit includes a roller conveyor (51) opened on the connecting shaft (5), a fixed sleeve (45), a rotating sleeve (47), and a roller shaft (48) rotatably connected to the rotating sleeve (47). The fixed sleeve (45) is fixedly installed in the second adjustment unit. The rotating sleeve (47) is rotatably assembled in the fixed sleeve (45) through a bearing. One end of the rotating sleeve (47) is fixedly connected to the second limiting plate (6).

9. The anti-collapse device according to claim 8, characterized in that, At least one roller track (51) is provided on the connecting shaft (5). In the second state, the roller shaft (48) rolls within the roller track (51).

10. The anti-collapse device according to claim 9, characterized in that, The feed end of the roller conveyor (51) is provided with a guide structure. The opening width of the guide structure gradually increases along the entry direction of the roller shaft (48) to guide the roller shaft (48) into the roller conveyor (51).

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