Constant tension non-contact electromagnetic braking device for high speed wrapping machine

Abstract

The application discloses a constant-tension non-contact electromagnetic braking device for a high-speed wrapping machine, relates to the technical field of wrapping machine unwinding tension control, and comprises a rack, an unwinding shaft, a non-contact electromagnetic braking assembly, a roll diameter follow-up mechanism, a magnetic adjustment mechanism and a tension swing arm fine adjustment mechanism. The non-contact electromagnetic braking assembly comprises a braking disc which rotates synchronously with the unwinding shaft and an electromagnetic braking unit which is fixed relative to the rack, and a non-contact working gap is formed between the braking disc and the electromagnetic braking unit. The roll diameter follow-up mechanism drives the magnetic adjustment mechanism to adjust a basic braking torque with the change of a wrapping tape roll diameter, and the tension swing arm fine adjustment mechanism drives the magnetic adjustment mechanism to fine adjust the braking torque with the change of a wrapping tape tension, so that the tension fluctuation is reduced, and the unwinding tension stability of the high-speed wrapping machine is improved.

Description

Technical Field

[0001] This invention relates to the field of unwinding tension control technology for wrapping machines, and in particular to a constant tension non-contact electromagnetic braking device for high-speed wrapping machines. Background Technology

[0002] High-speed wrapping machines are commonly used wrapping equipment in the processing of wires, cables, wire harnesses, conductors, and other long strip substrates. They are typically used to continuously wrap thin strip materials such as mica tape, polyester tape, non-woven tape, shielding tape, and insulating tape around the outer circumference of the object being wrapped, according to a predetermined helix angle and overlap ratio. During the wrapping process, the wrapping tape is usually continuously released from a wrapping tape reel mounted on an unwinding shaft, guided and tensioned, and then enters the wrapping head. The wrapping operation is completed with the relative movement of the wrapping head or the object being wrapped. Therefore, the tension stability of the wrapping tape during the unwinding process directly affects the unfolding posture, bonding angle, overlap width, and wrapping tightness of the wrapping tape.

[0003] For high-speed wrapping machines, the wrapping speed is high, and the wrapping tape completes high-speed unwinding, guiding, and wrapping in a short time. If the wrapping tape tension is too low, problems such as loose tape, wrinkles, deviation, and loose overlap may occur. If the wrapping tape tension is too high, it may cause the wrapping tape to be stretched and deformed, break, or cause the wrapped object to be subjected to additional pulling, affecting the quality of subsequent processing. Especially during high-speed continuous wrapping, even if the wrapping tape does not break or loosen significantly, periodic fluctuations in tension may lead to changes in the wrapping pitch, unstable overlap rate, and uneven coating thickness, thus affecting the consistency and reliability of the finished product.

[0004] Existing high-speed wrapping machines typically have braking or damping devices at the unwinding end to apply a certain braking torque to the unwinding shaft or wrapping reel, limiting the free rotation of the wrapping reel and maintaining the wrapping tension. Common braking methods include friction plate braking, spring-loaded damping braking, magnetic powder braking, and ordinary electromagnetic braking. Among these, friction plate braking and spring-loaded damping braking have relatively simple structures, but they are prone to wear, heat generation, and torque attenuation during high-speed operation, and the braking torque is greatly affected by the state of the friction pair. Although magnetic powder braking and ordinary electromagnetic braking can improve mechanical wear to some extent, their braking torque usually still relies on a fixed current, a fixed magnetic circuit, or manually set parameters, making it difficult to match in a timely manner with changes in the unwinding state.

[0005] During actual unwinding, the diameter of the wrapping tape reel continuously decreases as the wrapping tape is released. However, the relationship between braking torque and the actual tension of the wrapping tape is not constant. For the same braking torque, the equivalent tension acting on the wrapping tape is different when the reel diameter is larger compared to when the reel diameter is smaller. Conversely, if it is desired to maintain the same or nearly the same target tension at full, medium, and small reel stages, the braking torque required by the braking device should change accordingly with the current reel diameter. Existing braking devices, if operating with fixed damping, fixed spring pressure, fixed excitation current, or manual intermittent adjustment, are prone to varying degrees of tension deviation in the early, middle, and late stages of unwinding, making it difficult to maintain stable tension throughout the entire unwinding cycle.

[0006] Furthermore, during continuous operation, high-speed wrapping machines may still experience instantaneous tension deviations due to factors such as changes in strip thickness, guide resistance, and traction speed fluctuations. If the braking device can only correct these deviations manually or through simple electronic control after they have already occurred, there is often a lag in adjustment, which can easily cause the wrapping strip to become momentarily too tight or too loose. This is especially true for thinner, narrower, or more easily deformable wrapping strips, as these tension shocks are more easily transmitted to subsequent wrapping stations, thus affecting the stability of the wrapping strip's posture before it enters the wrapping station.

[0007] While non-contact electromagnetic braking can reduce friction, wear, and dust pollution, making it suitable for braking high-speed rotating components, ordinary non-contact electromagnetic braking devices, if using fixed air gaps, fixed magnetic circuits, or fixed excitation conditions, still struggle to automatically adapt their output braking torque to changes in the winding reel diameter and tension fluctuations. In other words, non-contact braking does not necessarily achieve constant tension unwinding. Without a structure capable of adaptively adjusting the braking torque based on changes in reel diameter and tension, a mismatch between the braking torque and the target tension may still occur.

[0008] Therefore, how to enable the braking device to adaptively adjust the braking torque according to the changes in the diameter of the wrapping tape reel and the fluctuations in the tension of the wrapping tape, based on non-contact electromagnetic braking, and reduce the tension drift and instantaneous fluctuations caused by changes in the diameter and tension disturbances during high-speed wrapping, is a technical problem that needs to be solved in this field. Summary of the Invention

[0009] This invention overcomes the shortcomings of the prior art and provides a constant tension non-contact electromagnetic braking device for high-speed wrapping machines.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a constant tension non-contact electromagnetic braking device for a high-speed wrapping machine, comprising: a frame, an unwinding shaft, a non-contact electromagnetic braking assembly, a roll diameter follow-up mechanism, a magnetic adjustment mechanism, and a tension swing arm fine-tuning mechanism.

[0011] The unwinding shaft is rotatably mounted on the frame for mounting the wrapping tape reel;

[0012] The non-contact electromagnetic braking assembly includes a brake disc that rotates synchronously with the unwinding shaft, and an electromagnetic braking unit that is fixed relative to the frame. A non-contact working gap is formed between the electromagnetic braking unit and the brake disc. The electromagnetic braking unit is used to apply braking torque to the brake disc.

[0013] The magnetic adjustment mechanism is configured corresponding to the magnetic circuit action area between the electromagnetic braking unit and the brake disc. At least a portion of the magnetic adjustment mechanism is movable relative to the magnetic circuit action area to change the amount of magnetic shielding within the magnetic circuit action area, thereby adjusting the braking torque.

[0014] The winding diameter follower mechanism has a follower end that abuts against the outer periphery of the wrapping tape reel, and a main adjustment output end that is connected to the magnetic adjustment mechanism. The follower end is displaced as the winding diameter of the wrapping tape reel changes, and drives the magnetic adjustment mechanism to adjust the basic braking torque through the main adjustment output end.

[0015] The tension swing arm fine-tuning mechanism has a tension guide end for winding the wrapping tape and a fine-tuning output end that is connected to the magnetic adjustment mechanism. The tension guide end swings with the change of the wrapping tape tension and drives the magnetic adjustment mechanism to fine-tune the braking torque based on the basic braking torque through the fine-tuning output end.

[0016] In a preferred embodiment of the present invention, the electromagnetic braking unit includes a magnetic yoke, an excitation coil, and a magnetic pole portion. The excitation coil is disposed on the magnetic yoke, and the magnetic pole portion is disposed facing the brake disc. The non-contact working gap is formed between the magnetic pole portion and the brake disc. The brake disc is fixedly sleeved on the unwinding shaft, or is synchronously rotatably connected to the unwinding shaft through a coupling.

[0017] In a preferred embodiment of the present invention, the roll diameter follower mechanism includes a follower roller, a roll diameter swing arm, a swing arm shaft, and a first reset member. The roll diameter swing arm is oscillatingly mounted on the frame via the swing arm shaft. The follower roller is rotatably disposed at one end of the roll diameter swing arm and forms the follower end. The first reset member acts on the roll diameter swing arm to keep the follower roller abutting against the outer periphery of the wrapping reel.

[0018] In a preferred embodiment of the present invention, the roll diameter follower mechanism further includes a compensation cam, which is drivenly connected to the roll diameter swing arm and abuts against or is connected to the magnetic adjustment mechanism through a transmission component; the compensation cam has a non-linear profile and is used to convert the oscillation amount of the roll diameter swing arm caused by the change in the roll diameter of the wrapping reel into a non-linear adjustment displacement of the magnetic adjustment mechanism.

[0019] In a preferred embodiment of the present invention, the magnetic adjustment mechanism includes a magnetic adjustment slide and a magnetic adjustment component mounted on the magnetic adjustment slide. The magnetic adjustment slide is movably disposed on the frame or the electromagnetic braking unit. The magnetic adjustment component is a magnetic shielding component, which is used to change the amount of magnetic shielding in the magnetic circuit action area.

[0020] In a preferred embodiment of the present invention, the magnetic adjustment slide is provided with a main adjustment input and a fine adjustment input. The main adjustment input is drivenly connected to the main adjustment output of the roll diameter follower mechanism, and the fine adjustment input is drivenly connected to the fine adjustment output of the tension swing arm fine adjustment mechanism, so that the roll diameter follower mechanism and the tension swing arm fine adjustment mechanism act on the same magnetic adjustment slide from different positions.

[0021] In a preferred embodiment of the present invention, the tension swing arm fine-tuning mechanism includes a tension swing arm, a tension guide roller, a tension swing arm rotating shaft, a second reset member, and a fine-tuning link. The tension swing arm is oscillatingly mounted on the frame via the tension swing arm rotating shaft. The tension guide roller is rotatably disposed on the tension swing arm and forms the tension guide end. The wrapping tape is wound around the tension guide roller. The second reset member acts on the tension swing arm. One end of the fine-tuning link is connected to the tension swing arm, and the other end is connected to the magnetic adjustment mechanism.

[0022] In a preferred embodiment of the present invention, the tension swing arm fine-tuning mechanism further includes a damper connected between the tension swing arm and the frame, for suppressing the high-frequency oscillation of the tension swing arm.

[0023] In a preferred embodiment of the present invention, the non-contact electromagnetic braking assembly further includes an air gap stabilizing structure, which includes at least one of an axial limiting bearing, a positioning spacer, and an elastic preload member. The air gap stabilizing structure is used to limit the axial movement of the brake disc relative to the magnetic pole portion to maintain the stability of the non-contact working gap; and / or, the electromagnetic braking unit includes a first magnetic pole portion and a second magnetic pole portion located on both sides of the brake disc, the first magnetic pole portion and the second magnetic pole portion being disposed opposite to each other so that the magnetic attraction forces on both sides of the brake disc are balanced.

[0024] In a preferred embodiment of the present invention, the tension swing arm is provided with an eccentric connecting part offset from the pivot axis of the tension swing arm; one end of the fine-tuning linkage is hinged to the eccentric connecting part, and the other end is drivenly connected to the magnetic adjustment mechanism through the fine-tuning output end; one end of the second reset member is connected to the tension swing arm, and the other end is connected to the frame or a pre-tightening adjustment seat provided on the frame; when the second reset member is connected to the pre-tightening adjustment seat, the pre-tightening adjustment seat is used to adjust the pre-tightening force of the second reset member to set the tension reference of the tension swing arm fine-tuning mechanism.

[0025] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0026] This invention incorporates a non-contact electromagnetic braking assembly at the unwinding shaft, creating a non-contact working gap between the brake disc, which rotates synchronously with the unwinding shaft, and the electromagnetic braking unit. Braking torque is applied to the brake disc via a magnetic circuit. Because there is no direct contact between the friction pads and the brake disc during braking, it reduces braking torque fluctuations caused by friction wear, friction dust, temperature rise attenuation, and changes in the friction pair state during high-speed winding, as is common in traditional friction-based braking systems. Compared to existing braking devices that rely on frictional compression to generate braking torque, this invention provides a smoother and more continuous basic braking output, reduces maintenance frequency, and provides a stable braking foundation for constant tension unwinding during high-speed winding.

[0027] This invention utilizes a diameter-following mechanism to bring the follower end against the outer periphery of the wrapping tape reel, and drives a magnetic adjustment mechanism to change the amount of magnetic shielding within the magnetic circuit's effective area as the reel's diameter changes. Since the reel's diameter continuously decreases during unwinding, the wrapping tape tension corresponding to the same braking torque differs at different reel diameters. This invention directly converts the diameter change into a mechanical adjustment action of the magnetic adjustment mechanism, allowing the basic braking torque to be adjusted synchronously with the diameter change. Compared to existing solutions with fixed damping, fixed spring pressure, fixed excitation conditions, or manual intermittent adjustment, this invention reduces tension drift between the full, middle, and small reel stages, keeping the wrapping tape closer to the target tension throughout the entire unwinding cycle, thereby improving the continuous stability of the wrapping process.

[0028] This invention further incorporates a tension swing arm fine-tuning mechanism, enabling changes in the wrapping tape tension to be transmitted to the magnetic adjustment mechanism via the tension guide end, tension swing arm, and fine-tuning output end. This allows for secondary fine-tuning based on the baseline braking torque generated by the roll diameter follower mechanism. Since the roll diameter follower mechanism primarily compensates for the mismatch in baseline braking torque caused by slow changes in roll diameter, instantaneous tension deviations may still occur during high-speed wrapping due to factors such as changes in tape thickness, guide resistance, and traction speed fluctuations. This invention uses the tension swing arm fine-tuning mechanism to provide mechanical feedback correction for these disturbances. Compared to existing structures that rely solely on single damping adjustment or single tension feedback, this invention can simultaneously adapt to continuous changes in roll diameter and instantaneous tension fluctuations, reducing the risk of instantaneous over-tightening, slackness, vibration, and deviation of the wrapping tape, resulting in a more stable tension state of the wrapping tape before it enters subsequent wrapping stations.

[0029] This invention further optimizes the magnetic adjustment action and braking output through structures such as a compensating cam, a damper, and an air gap stabilizing structure. The compensating cam converts the swing of the winding diameter swing arm into a nonlinear adjustable displacement that better meets the requirements of braking torque changes. The damper suppresses high-frequency vibration of the tension swing arm under high-speed disturbances, and the air gap stabilizing structure reduces axial movement of the brake disc relative to the magnetic poles. Compared to ordinary braking devices that are only suitable for fixed damping or low-speed unwinding, this invention improves braking stability under high-speed continuous operation, reduces wrinkles, belt breaks, loose belts, pitch changes, and uneven overlap rates caused by tension fluctuations, thereby improving the quality of the wrapping layer and product consistency. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0032] Figure 2 This is a schematic diagram of the non-contact electromagnetic braking assembly in this invention;

[0033] Figure 3 This is a schematic diagram of the linkage between the roll diameter follower mechanism and the magnetic adjustment mechanism in this invention;

[0034] Figure 4 This is a schematic diagram of the magnetic adjustment mechanism in this invention;

[0035] Figure 5 This is a schematic diagram of the tension swing arm fine-tuning mechanism in this invention;

[0036] Figure 6 This is a schematic diagram of the air gap stabilizing structure in this invention;

[0037] In the diagram: 1. Frame; 2. Unwinding shaft; 3. Wrapping reel; 4. Wrapping tape; 5. Non-contact electromagnetic braking assembly; 51. Brake disc; 52. Electromagnetic braking unit; 521. Magnetic yoke; 522. Excitation coil; 523. Magnetic pole section; 523a. First magnetic pole section; 523b. Second magnetic pole section; 53. Non-contact working gap; 54. Coupling; 55. Magnetic circuit action area; 6. Coil diameter follower mechanism; 61. Follower end; 62. Follower roller; 63. Coil diameter swing arm; 64. Swing arm shaft; 65. First reset component; 66. Main adjustment output end; 67. 68. Compensating cam; 69. Transmission component; 70. Nonlinear profile; 81. Magnetizing mechanism; 72. Magnetizing slide; 73. Magnetizing component; 74. Magnetic shielding component; 75. Main adjustment input; 86. Fine adjustment input; 87. Guide slide rail; 88. Tension swing arm fine adjustment mechanism; 89. Tension guide end; 80. Tension guide roller; 81. Tension swing arm; 82. Tension swing arm shaft; 83. Second reset component; 84. Fine adjustment linkage; 85. Fine adjustment output end; 86. Damper; 97. Air gap stabilizing structure; 98. Axial limit bearing; 99. Positioning spacer; 90. Elastic preload component. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0040] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0041] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this application based on the specific circumstances.

[0042] like Figures 1 to 6 As shown, this embodiment provides a constant tension non-contact electromagnetic braking device for a high-speed wrapping machine, including a frame 1, an unwinding shaft 2, a non-contact electromagnetic braking assembly 5, a diameter follower mechanism 6, a magnetic adjustment mechanism 7, and a tension swing arm fine-tuning mechanism 8. The unwinding shaft 2 is rotatably mounted on the frame 1 for mounting the wrapping reel 3; the non-contact electromagnetic braking assembly 5 cooperates with the unwinding shaft 2 to apply braking torque to the unwinding shaft 2; the diameter follower mechanism 6 generates mechanical displacement according to the change in the diameter of the wrapping reel 3 and transmits the mechanical displacement to the magnetic adjustment mechanism 7; the tension swing arm fine-tuning mechanism 8 swings according to the change in tension of the wrapping tape 4 and transmits the swing to the magnetic adjustment mechanism 7; the magnetic adjustment mechanism 7 is correspondingly arranged with the magnetic circuit action area 55 of the non-contact electromagnetic braking assembly 5, and its magnetic adjustment component can move relative to the magnetic circuit action area 55 to change the amount of magnetic shielding within the magnetic circuit action area 55, thereby adjusting the braking torque output by the non-contact electromagnetic braking assembly 5 to the unwinding shaft 2.

[0043] The core of this invention lies in not simply installing a common electromagnetic brake on the unwinding shaft 2, but rather converting the changes in the diameter of the wrapping reel 3 and the tension changes of the wrapping tape 4 into two separate mechanical inputs, which then act together on the magnetic adjustment mechanism 7. The diameter follow-up mechanism 6 adjusts the base position of the magnetic adjustment mechanism 7 according to the slow changes in the diameter of the wrapping reel 3, thereby forming a base braking torque that varies with the diameter. The tension swing arm fine-tuning mechanism 8 performs secondary fine-tuning of the magnetic adjustment mechanism 7 based on the instantaneous tension fluctuations of the wrapping tape 4, thus superimposing real-time tension correction onto the base braking torque. The magnetic adjustment mechanism 7 then changes the amount of magnetic shielding within the magnetic circuit action area 55, causing the braking torque to change in the direction that counteracts tension deviations. Therefore, the base tension drift caused by diameter changes and the instantaneous tension fluctuations during high-speed wrapping can both be adaptively adjusted through the mechanical structure.

[0044] The following detailed descriptions, in conjunction with the accompanying drawings, illustrate the specific structure, connections, and working processes of each of the aforementioned mechanisms.

[0045] Example 1:

[0046] like Figure 1 As shown, the constant tension non-contact electromagnetic braking device of this embodiment is installed at the unwinding end of the high-speed wrapping machine. The frame 1 serves as the mounting base for each mechanism and can be fixed to the unwinding end of the high-speed wrapping machine, or it can be part of the unwinding component of the high-speed wrapping machine. The unwinding shaft 2 is rotatably mounted on the frame 1 via bearings, and the wrapping tape reel 3 is fitted onto the unwinding shaft 2 and can rotate synchronously with the unwinding shaft 2. After the wrapping tape 4 is drawn from the wrapping tape reel 3, it is guided and tensioned before entering the subsequent wrapping station.

[0047] During the wrapping process, the wrapping tape 4 is continuously pulled by the subsequent wrapping station or traction mechanism, and the wrapping tape reel 3 rotates accordingly. If the unwinding shaft 2 is in a free-rotating state, the wrapping tape reel 3 is prone to excessive unwinding due to inertia, causing the wrapping tape 4 to slack; if the unwinding shaft 2 is subjected to excessive braking torque, the wrapping tape 4 is prone to being tightened or even breaking. Therefore, in this embodiment, a non-contact electromagnetic braking component 5 is provided at the unwinding shaft 2, so that it can apply an adjustable torque to the unwinding shaft 2 without directly contacting the brake disc 51.

[0048] like Figure 2As shown, the non-contact electromagnetic braking assembly 5 includes a brake disc 51 and an electromagnetic braking unit 52. The brake disc 51 rotates synchronously with the unwinding shaft 2. Specifically, the brake disc 51 can be fixedly sleeved on the unwinding shaft 2, or it can be connected to the unwinding shaft 2 for synchronous rotation via a coupling 54. The electromagnetic braking unit 52 is fixedly disposed relative to the frame 1. The electromagnetic braking unit 52 includes a magnetic yoke 521, an excitation coil 522, and a magnetic pole portion 523. The excitation coil 522 is disposed on the magnetic yoke 521, and the magnetic pole portion 523 is disposed facing the brake disc 51, forming a non-contact working gap 53 between the magnetic pole portion 523 and the brake disc 51. The non-contact working gap 53 prevents mechanical contact between the magnetic pole portion 523 and the brake disc 51, thereby avoiding the wear, heat generation, dust, and unstable friction pair conditions common in friction plate braking systems.

[0049] When the excitation coil 522 is energized, the magnetic yoke 521 and the magnetic pole portion 523 form a magnetic circuit. The magnetic field acts on the brake disc 51, which rotates with the unwinding shaft 2, causing the brake disc 51 to be subjected to a braking torque that hinders its rotation. The brake disc 51 can be made of a magnetically conductive material or a conductive metal material suitable for generating eddy current braking. In different embodiments, the non-contact electromagnetic braking assembly 5 can adopt a hysteresis braking structure or an eddy current braking structure. Regardless of the specific electromagnetic braking form used, as long as it can maintain a non-contact working gap 53 between the magnetic pole portion 523 and the brake disc 51, and apply a braking torque to the brake disc 51 through the magnetic circuit, it is applicable to this invention.

[0050] In this embodiment, the braking torque of the non-contact electromagnetic braking assembly 5 can be formed not only by the energization state of the excitation coil 522, but also by changing the amount of magnetic shielding in the magnetic circuit action area 55 through the magnetic adjustment mechanism 7. That is to say, this embodiment does not simply rely on fixed excitation conditions to output a fixed braking torque, but uses the diameter follower mechanism 6 and the tension swing arm fine adjustment mechanism 8 to drive the magnetic adjustment mechanism 7, so that the magnetic circuit state is mechanically adjusted according to the changes in the diameter of the wrapping reel 3 and the tension of the wrapping tape 4.

[0051] like Figure 3 As shown, the roll diameter follower mechanism 6 includes a follower roller 62, a roll diameter swing arm 63, a swing arm shaft 64, a first reset member 65, and a main adjustment output end 66. The roll diameter swing arm 63 is oscillatingly mounted on the frame 1 via the swing arm shaft 64. The follower roller 62 is rotatably disposed at one end of the roll diameter swing arm 63, forming a follower end 61 for contacting the outer periphery of the wrapping reel 3. The first reset member 65 acts on the roll diameter swing arm 63, ensuring that the follower roller 62 always tends to contact the outer periphery of the wrapping reel 3. The first reset member 65 can be a tension spring, compression spring, torsion spring, elastic sheet, or other elastic element capable of providing restoring force, as long as it can keep the follower roller 62 in contact with the outer periphery of the wrapping reel 3.

[0052] During the unwinding process of the wrapping tape 4, the outer diameter of the wrapping tape reel 3 gradually decreases as the wrapping tape 4 is continuously unwound. Because the follower roller 62 is always pressed against the outer circumference of the wrapping tape reel 3 under the action of the first reset member 65, as the wrapping tape reel 3 gradually changes from a full reel state to a medium reel state and then to a small reel state, the follower roller 62 moves towards the unwinding shaft 2 along with the outer circumference of the wrapping tape reel 3, causing the diameter swing arm 63 to swing around the swing arm pivot 64 accordingly. The swing of the diameter swing arm 63 is transmitted to the magnetic adjustment mechanism 7 through the main adjustment output end 66, thus directly converting the change in the diameter of the wrapping tape reel 3 into the mechanical adjustment input of the magnetic adjustment mechanism 7.

[0053] Since the relationship between the change in the diameter of the wrapping reel 3 and the change in the required braking torque is usually not a simple linear one, directly transmitting the swing of the diameter swing arm 63 to the magnetizing mechanism 7 via a simple linear linkage may result in insufficient compensation during the large diameter stage or excessive compensation during the small diameter stage. To improve the matching degree between the diameter compensation and the actual braking torque requirement, the diameter follower mechanism 6 in this embodiment also includes a compensation cam 67. The compensation cam 67 is drivenly connected to the diameter swing arm 63, has a non-linear profile 69, and abuts against the magnetizing mechanism 7, or is connected to the magnetizing mechanism 7 via a transmission member 68.

[0054] When the diameter swing arm 63 oscillates with the change in the diameter of the wrapping reel 3, it drives the compensating cam 67 to rotate. The nonlinear profile 69 of the compensating cam 67 cooperates with the magnetic adjustment mechanism 7 to convert the angular displacement of the diameter swing arm 63 into the nonlinear adjustment displacement of the magnetic adjustment mechanism 7. By changing the shape of the nonlinear profile 69, the magnetic adjustment mechanism 7 can obtain different displacement change rates in the full reel stage, the middle reel stage, and the small reel stage, thereby making the adjustment action of the magnetic adjustment mechanism 7 closer to the braking torque change law required to maintain the target tension of the wrapping tape 4. The compensating cam 67 can be coaxially set with the diameter swing arm 63, or it can be connected to the diameter swing arm 63 through gears, connecting rods, synchronous belts, shift forks, or other transmission components 68.

[0055] like Figure 4 As shown, the magnetic adjustment mechanism 7 includes a magnetic adjustment slide 71, a magnetic adjustment component 72, and a guide rail 75. The guide rail 75 is fixed to the frame 1 or the electromagnetic braking unit 52. The magnetic adjustment slide 71 is movably mounted on the guide rail 75, allowing the magnetic adjustment slide 71 to move closer to, further away from, or laterally across the magnetic circuit action area 55 in a predetermined direction. The magnetic adjustment component 72 is mounted on the magnetic adjustment slide 71 and moves synchronously with it. The magnetic adjustment slide 71 is provided with a main adjustment input 73 and a fine adjustment input 74. The main adjustment input 73 is used for transmission connection with the main adjustment output 66 of the roll diameter follower mechanism 6, and the fine adjustment input 74 is used for transmission connection with the fine adjustment output 87 of the tension swing arm fine adjustment mechanism 8.

[0056] In a preferred embodiment, the adjusting element 72 is a shielding element 722. The shielding element 722 is disposed near the magnetic circuit action region 55 between the magnetic pole portion 523 and the brake disc 51, or at a position capable of influencing the magnetic flux between the magnetic pole portion 523 and the brake disc 51. The shielding element 722 can be made of a high-permeability magnetic material, or a composite of a high-permeability magnetic material and a non-magnetic support element. When the shielding element 722 moves relative to the magnetic circuit action region 55, it can bypass, divert, or shield the magnetic flux flowing from the magnetic pole portion 523 to the brake disc 51, thereby changing the effective magnetic flux acting on the brake disc 51. As the adjusting slide 71 moves, the shielding element 722 can change its insertion depth into the magnetic circuit action region 55, thereby changing the effective magnetic flux acting on the brake disc 51.

[0057] Specifically, when the depth of the magnetic shielding member 722 inserted into the magnetic circuit action area 55 increases, the effective magnetic flux of the magnetic pole portion 523 acting on the brake disc 51 decreases, and the braking torque generated by the non-contact electromagnetic braking assembly 5 on the brake disc 51 decreases; when the degree to which the magnetic shielding member 722 exits the magnetic circuit action area 55 increases, the effective magnetic flux of the magnetic pole portion 523 acting on the brake disc 51 increases, and the braking torque generated by the non-contact electromagnetic braking assembly 5 on the brake disc 51 increases. Therefore, the winding diameter follower mechanism 6 or the tension swing arm fine-tuning mechanism 8 only needs to mechanically drive the magnetic adjustment slide 71 to generate displacement, thus changing the braking torque without contacting the high-speed rotating brake disc 51.

[0058] The specific shape of the magnetic shielding component 722 can be sheet-like, block-like, arc-shaped plate-like, annular segment-like, or other structures adapted to the magnetic circuit action area 55. As the magnetic shielding component 722 moves with the magnetic adjustment slide 71, its insertion depth into the magnetic circuit action area 55 changes, thereby altering the amount of magnetic shielding within the magnetic circuit action area 55. This embodiment does not impose any particular limitation on this. During movement, the magnetic shielding component 722 maintains a clearance gap with both the magnetic pole portion 523 and the brake disc 51. The magnetic shielding component 722 does not contact the brake disc 51, which rotates synchronously with the unwinding shaft 2, to ensure that the non-contact electromagnetic braking assembly 5 maintains a non-contact braking state during magnetic adjustment.

[0059] In this embodiment, when the winding diameter follower mechanism 6 drives the magnetic adjustment mechanism 7 through the main adjustment output terminal 66, its adjustment direction is set as follows: when the winding diameter of the wrapping reel 3 is large, the magnetic adjustment mechanism 7 causes the non-contact electromagnetic braking component 5 to output a larger basic braking torque; when the winding diameter of the wrapping reel 3 is small, the magnetic adjustment mechanism 7 causes the non-contact electromagnetic braking component 5 to output a smaller basic braking torque. Taking the shielding element 722 as an example, in the full reel state, the follower roller 62 is located away from the unwinding shaft 2, and the winding diameter swing arm 63, through the compensation cam 67, causes the magnetic adjustment slide 71 to be in a position that causes the shielding element 722 to be inserted less into the magnetic circuit action area 55. At this time, the effective magnetic flux is large, and the basic braking torque is large. As the winding diameter of the wrapping reel 3 decreases, the follower roller 62 gradually moves inward, and the winding diameter swing arm 63, through the compensation cam 67, drives the magnetic adjustment slide 71 to move, causing the shielding element 722 to be inserted deeper into the magnetic circuit action area 55, the effective magnetic flux gradually decreases, and the basic braking torque decreases accordingly. Since larger roll diameters typically require larger braking torques and smaller roll diameters typically require smaller braking torques under the same target tension, the aforementioned mechanical servo relationship can reduce tension drift between the full roll, middle roll, and small roll stages.

[0060] It should be noted that when using different magnetic circuit structures or different transmission arrangements, the relationship between the moving direction of the adjusting magnetic slide 71 and the increase or decrease of the braking torque can be adjusted by reversing linkage, reverse cam, gear reversing component, or the opposite arrangement of adjusting magnetic component 72. As long as the adjustment trend of relatively large basic braking torque when the roll diameter is large and relatively small basic braking torque when the roll diameter is small is ultimately satisfied, it falls within the scope of the present invention.

[0061] like Figure 5 As shown, the tension swing arm fine-tuning mechanism 8 includes a tension guide roller 82, a tension swing arm 83, a tension swing arm shaft 84, a second reset member 85, a fine-tuning link 86, and a fine-tuning output end 87. The tension swing arm 83 is oscillatingly mounted on the frame 1 via the tension swing arm shaft 84. The tension guide roller 82 is rotatably mounted on the tension swing arm 83 and forms a tension guide end 81 for the wrapping tape 4 to be wound or abutted. After being led out from the wrapping tape reel 3, the wrapping tape 4 passes over the tension guide roller 82 and then enters the subsequent guiding component or the subsequent wrapping station. The second reset member 85 acts on the tension swing arm 83 to provide a reference restoring force to the tension swing arm 83. The tension swing arm 83 is provided with an eccentric connecting part that deviates from the tension swing arm shaft 84. One end of the fine-tuning link 86 is hinged to the eccentric connecting part, and the other end is connected to the fine-tuning input part 74 of the magnetic adjustment mechanism 7 via the fine-tuning output end 87.

[0062] The second reset member 85 can be a tension spring, compression spring, torsion spring, elastic sheet, or gas spring. One end of it can be connected to the tension swing arm 83, and the other end can be connected to the frame 1 or a pre-tension adjustment seat mounted on the frame 1. The pre-tension adjustment seat is used to adjust the pre-tension force of the second reset member 85 to set the tension reference of the tension swing arm fine-tuning mechanism 8. In a preferred embodiment, the pre-tension force of the second reset member 85 can be adjusted by adjusting the screw, adjusting the knob, or the scale seat to set different tension references according to different materials, widths, thicknesses, or process requirements of the wrapping tape 4. This pre-tension force adjustment structure is not a necessary feature of claim 1 of the present invention, but it can be used as a preferred configuration of the tension swing arm fine-tuning mechanism 8.

[0063] When the tension of the wrapping tape 4 increases, the tension guide roller 82 experiences increased traction from the wrapping tape 4. Under this traction, the tension swing arm 83 swings in the first direction and, via the fine-tuning linkage 86, drives the magnetic adjustment mechanism 7 to perform a fine-tuning action. This fine-tuning action is designed to reduce the braking torque of the non-contact electromagnetic braking assembly 5. Taking the magnetic shielding component 722 as an example, when the tension increases, the fine-tuning linkage 86 moves the magnetic adjustment slide block 71, causing the magnetic shielding component 722 to further insert into the magnetic circuit action area 55, thereby reducing the effective magnetic flux acting on the brake disc 51, lowering the braking torque, and preventing the wrapping tape 4 from becoming too tight.

[0064] When the tension of the wrapping tape 4 decreases, the traction force on the tension guide roller 82 decreases, and the second reset member 85 drives the tension swing arm 83 to reset in a second direction opposite to the first direction. The tension swing arm 83 drives the magnetic adjustment mechanism 7 to reverse its action through the fine-tuning linkage 86. The direction of this reverse action is set to increase the braking torque of the non-contact electromagnetic braking assembly 5. Taking the magnetic shielding member 722 as an example, when the tension decreases, the fine-tuning linkage 86 moves the magnetic adjustment slide 71 to the position where the magnetic shielding member 722 exits the magnetic circuit action area 55. The effective magnetic flux acting on the brake disc 51 increases, and the braking torque increases, thereby suppressing the wrapping tape reel 3 from unwinding too quickly and reducing the slack of the wrapping tape 4.

[0065] It should be noted that, under different installation orientations, the swing direction of the tension swing arm 83 and the direction of increase or decrease of the braking torque of the magnetic adjustment mechanism 7 can be adjusted by the opposite arrangement of the reversing link, the reverse hinge point, the swing reversing component, or the magnetic adjustment component 72; as long as the adjustment trend of decreasing braking torque when the tension increases and increasing braking torque when the tension decreases is ultimately satisfied, it falls within the scope of the present invention.

[0066] Thus, the tension swing arm fine-tuning mechanism 8 forms a mechanical tension feedback structure. It does not require signal detection by a tension sensor followed by controller calculation, nor does it rely on complex electronic control algorithms. Instead, it directly utilizes the swing of the tension swing arm 83 caused by the tension change of the wrapping tape 4 to apply instantaneous mechanical fine-tuning to the magnetizing mechanism 7. This structure is particularly suitable for operating conditions with frequent tension disturbances and high response time requirements during high-speed wrapping.

[0067] In this embodiment, the roll diameter follower mechanism 6 and the tension swing arm fine-tuning mechanism 8 work together on the same magnetic adjustment mechanism 7. Specifically, the magnetic adjustment slide 71 is provided with a main adjustment input 73 and a fine-tuning input 74. The main adjustment input 73 is connected to the main adjustment output 66 of the roll diameter follower mechanism 6, and the fine-tuning input 74 is connected to the fine-tuning output 87 of the tension swing arm fine-tuning mechanism 8. The main adjustment input 73 and the fine-tuning input 74 can be respectively located on different sides, at different heights, or at different ends of the magnetic adjustment slide 71, so that the two input mechanisms can respectively apply adjustment displacement to the magnetic adjustment slide 71. The main adjustment input 73 can abut against the compensation cam 67, or it can be connected to the compensation cam 67 through the transmission member 68; the fine-tuning input 74 can be hinged to the fine-tuning linkage 86, slide against it, or be connected through a ball joint connector.

[0068] To avoid over-constraint when the main adjustment output 66 and the fine adjustment output 87 act simultaneously on the same magnetic adjustment slide 71, a floating connection structure can be provided between the main adjustment input 73 and the main adjustment output 66, and / or between the fine adjustment input 74 and the fine adjustment output 87. The floating connection structure can be an elongated hole connection, a sliding groove connection, a ball joint connection, an elastic preload connection, or a hinge structure with gap compensation. This allows the roll diameter follower mechanism 6 to determine the base position of the magnetic adjustment slide 71, while the tension swing arm fine adjustment mechanism 8 can superimpose a small range of corrective displacement at this base position, thereby preventing the two sets of mechanical inputs from jamming against each other.

[0069] In this dual-input structure, the diameter follower mechanism 6 is mainly used to determine the basic position of the magnetic adjustment slide 71 based on the diameter change of the wrapping reel 3, thereby forming the basic braking torque; the tension swing arm fine-tuning mechanism 8 applies a small range of correction displacement to the basic position of the magnetic adjustment slide 71, thereby performing secondary fine-tuning of the basic braking torque. In other words, the diameter follower mechanism 6 handles the slow variable change of the wrapping reel 3 from full to small, while the tension swing arm fine-tuning mechanism 8 handles the fast variable change of the wrapping tape 4 caused by changes in tape thickness, guide resistance, traction speed fluctuations, or local disturbances during high-speed operation. Both act together on the same magnetic adjustment slide 71, enabling the braking torque of the non-contact electromagnetic braking assembly 5 to be continuously adjusted with the diameter change and to provide mechanical feedback to instantaneous tension fluctuations.

[0070] In actual operation, the wrapping reel 3 is first installed on the unwinding shaft 2, allowing the wrapping tape 4 to be drawn out from the wrapping reel 3 and pass over the tension guide roller 82 before entering the subsequent wrapping station. Then, the excitation coil 522 is energized, and the electromagnetic braking unit 52 applies a braking torque to the brake disc 51 through the magnetic circuit. The brake disc 51 drives the unwinding shaft 2 to form basic damping. When the wrapping reel 3 is in a full-reel state, the follower roller 62 is in the corresponding large-diameter position. The diameter swing arm 63 and the compensation cam 67 position the magnetic adjustment slide 71 in a position with a larger basic braking torque to adapt to the braking torque required to maintain the target tension under large-diameter conditions.

[0071] As the wrapping tape 4 is continuously released, the diameter of the wrapping tape reel 3 gradually decreases. The follower roller 62 moves inward under the action of the first reset member 65, and the diameter swing arm 63 oscillates around the swing arm axis 64, driving the compensation cam 67 to rotate. The compensation cam 67 pushes the magnetic adjustment slide block 71 along the guide rail 75 via the nonlinear profile 69, causing the magnetic shielding member 722 to gradually change its insertion depth into the magnetic circuit action area 55, so that the basic braking torque decreases accordingly as the diameter of the wrapping tape reel 3 decreases. Because the basic braking torque automatically adjusts with the change in diameter, the tension difference of the same wrapping tape reel 3 at the full, medium, and small reel stages is reduced.

[0072] When the tension of the wrapping tape 4 momentarily exceeds a certain level during operation, the traction force on the tension guide roller 82 increases, the tension swing arm 83 swings in the first direction, and through the fine-tuning linkage 86, it drives the magnetic adjustment slide 71 or the magnetic adjustment component 72 to move slightly in the direction of reducing the braking torque, thus causing the tension of the wrapping tape 4 to decrease. When the tension of the wrapping tape 4 momentarily decreases, the second reset component 85 drives the tension swing arm 83 to reset in the second direction, and through the fine-tuning linkage 86, it drives the magnetic adjustment slide 71 or the magnetic adjustment component 72 to move slightly in the direction of increasing the braking torque, thus increasing the braking torque on the unwinding shaft 2, suppressing the excessively fast unwinding tendency of the wrapping tape reel 3, and causing the tension of the wrapping tape 4 to recover. Through the above actions, the basic tension drift caused by the change in roll diameter and the tension fluctuation caused by momentary disturbances can both be adjusted by the mechanical structure, thereby maintaining a relatively stable tension state of the wrapping tape 4 before entering the subsequent wrapping station.

[0073] Example 2:

[0074] This embodiment, based on Embodiment 1, further optimizes the high-speed stability of the tension swing arm fine-tuning mechanism 8 and the non-contact electromagnetic braking assembly 5. During high-speed wrapping machine operation, the wrapping belt 4 operates at a high speed, and the belt may experience high-frequency micro-tension disturbances as it passes through the guide rollers and tension guide rollers 82. If the tension swing arm 83 is too sensitive, the fine-tuning linkage 86 may cause the magnetic adjustment mechanism 7 to frequently reciprocate, resulting in small oscillations in the braking torque. On the other hand, although the non-contact electromagnetic braking assembly 5 avoids friction and wear, its braking torque is easily affected by changes in the non-contact working gap 53. If the brake disc 51 experiences axial movement or swaying during high-speed rotation, it may also lead to periodic fluctuations in the braking torque. Therefore, this embodiment further incorporates a damper 88 and an air gap stabilizing structure 9.

[0075] like Figure 5 As shown, the tension swing arm fine-tuning mechanism 8 also includes a damper 88; the damper 88 is connected between the tension swing arm 83 and the frame 1 and is used to suppress the high-frequency swing of the tension swing arm 83; the damper 88 can be a hydraulic damper, a pneumatic damper, a friction damper, an elastic damper, or other damping structures that can absorb the swing impact.

[0076] When a short-term high-frequency disturbance occurs in the wrapping tape 4, the tension guide roller 82 transmits the disturbance force to the tension swing arm 83. The damper 88 absorbs the rapid swing energy of the tension swing arm 83, preventing it from continuously oscillating due to minor disturbances, thus avoiding unnecessary frequent adjustments caused by the fine-tuning linkage 86 driving the magnetic adjustment mechanism 7. Through the damper 88, the tension swing arm fine-tuning mechanism 8 retains its mechanical response to tension changes while reducing the risk of over-adjustment under high-speed disturbances.

[0077] like Figure 6 As shown, the non-contact electromagnetic braking assembly 5 also includes an air gap stabilizing structure 9. The air gap stabilizing structure 9 is used to limit the axial movement of the brake disc 51 relative to the magnetic pole portion 523, thereby maintaining the stability of the non-contact working clearance 53. The air gap stabilizing structure 9 may include at least one of an axial limiting bearing 91, a positioning spacer 92, and an elastic preload member 93. The axial limiting bearing 91 may be disposed on both axial sides of the unwinding shaft 2 or the brake disc 51 to limit the axial movement of the brake disc 51 along the unwinding shaft 2; the positioning spacer 92 may be disposed between the brake disc 51 and an adjacent bearing, shoulder, or frame 1 to determine the axial position of the brake disc 51 relative to the magnetic pole portion 523; the elastic preload member 93 may be a disc spring, an elastic washer, a wave spring, or other elastic element, used to apply a preload force to the axial limiting bearing 91 or the positioning spacer 92 to reduce axial movement caused by assembly clearance.

[0078] In another embodiment, the electromagnetic braking unit 52 includes a first magnetic pole portion 523a and a second magnetic pole portion 523b located on both sides of the brake disc 51. The first magnetic pole portion 523a and the second magnetic pole portion 523b are arranged opposite to each other, and the brake disc 51 is located between the first magnetic pole portion 523a and the second magnetic pole portion 523b, forming a non-contact working gap 53 between the brake disc 51 and the first magnetic pole portion 523a and the second magnetic pole portion 523b, respectively. By using the magnetic pole portions arranged opposite to each other on both sides, the magnetic attraction forces on both sides of the brake disc 51 can be balanced, reducing the axial displacement of the brake disc 51 caused by unilateral magnetic attraction forces. This dual-sided magnetic pole structure can improve both the utilization rate of the magnetic circuit and the stability of the non-contact working gap 53 under high-speed rotation.

[0079] In the non-contact electromagnetic braking assembly 5, the braking torque is closely related to the gap between the magnetic pole portion 523 and the brake disc 51. If the brake disc 51 experiences axial movement, end face runout, or offset due to unilateral magnetic attraction during high-speed rotation, the magnetic flux distribution will change accordingly, causing periodic fluctuations in the braking torque. In this embodiment, one or more combinations of the axial limiting bearing 91, positioning spacer 92, elastic preload member 93, and dual-sided magnetic pole structure are used to limit the positional change of the brake disc 51 relative to the magnetic pole portion 523, keeping the non-contact working gap 53 within a relatively stable range. As a result, the adjustment of the braking torque by the magnetic adjustment mechanism 7 is more controllable, and the adjustment effects of the roll diameter follower mechanism 6 and the tension swing arm fine-tuning mechanism 8 are also more stable.

[0080] Example 3:

[0081] In the above embodiments, the magnetic adjustment mechanism 7 is mainly described by moving the magnetic shielding component 722 driven by the magnetic adjustment slide 71, but the present invention is not limited to a linear sliding structure. The magnetic adjustment mechanism 7 can also adopt a swinging magnetic shielding plate, a rotating magnetic shielding ring, a magnetic shielding sheet that can move along the guide, or other structures that can change the amount of magnetic shielding. The magnetic shielding component 722 can move in a straight line, or it can swing or rotate around a fixed axis; as long as it can change the amount of magnetic shielding within the magnetic circuit action area 55 under the drive of the roll diameter follower mechanism 6 and the tension swing arm fine adjustment mechanism 8, the purpose of the present invention can be achieved.

[0082] In the above embodiment, the roll diameter follower mechanism 6 senses changes in roll diameter by having the follower roller 62 abut against the outer periphery of the wrapping reel 3, but the present invention is not limited to this form. The follower end 61 can also be an arc-shaped contact block, a low-friction slider, a flexible pressure roller, a swing pressure arm, or other mechanical contact components that can generate displacement as the position of the outer periphery of the wrapping reel 3 changes. To reduce indentations on the outer wrapping tape 4 of the wrapping reel 3, a rubber layer, a polyurethane layer, or other flexible wear-resistant layer can be provided on the outer periphery of the follower roller 62; the follower roller 62 can also have a larger width or an arc-shaped outer contour to reduce the unit contact pressure.

[0083] In the above embodiments, the compensating cam 67 is used to realize the nonlinear conversion between the swing amount of the roll diameter swing arm 63 and the displacement of the magnetic adjustment mechanism 7, but the present invention is not limited to a cam structure. A variable arm long linkage mechanism, an eccentric wheel mechanism, a gear-rack transmission mechanism with varying ratios, a Geneva mechanism, or a multi-segment linkage mechanism can also be used to realize the nonlinear displacement conversion. As long as the structure can make the displacement of the magnetic adjustment mechanism 7 correspond to the change in the required basic braking torque according to the change in the roll diameter of the wrapping reel 3, it can be used as an equivalent replacement structure for the compensating cam 67.

[0084] In the above embodiments, the tension swing arm fine-tuning mechanism 8 cooperates with the wrapping tape 4 through the tension guide roller 82, but the present invention is not limited to a single tension guide roller 82. The tension guide end 81 may include one tension guide roller 82, or it may include a wrapping path formed by two or more guide rollers, so that the wrapping tape 4 wraps around the tension guide end 81 at a certain wrap angle. By adjusting the wrap angle of the wrapping tape 4 on the tension guide roller 82, the response sensitivity of the tension swing arm 83 to tension changes can be changed, thereby adapting to wrapping tapes 4 of different thicknesses, widths and materials.

[0085] In the above embodiments, the electromagnetic braking unit 52 of the non-contact electromagnetic braking assembly 5 is fixedly mounted relative to the frame 1, and the brake disc 51 rotates with the unwinding shaft 2. However, in other embodiments, the magnetic yoke 521 and the excitation coil 522 can be configured as a ring structure, a semi-ring structure, or a multi-pole distribution structure depending on the installation space; the magnetic pole portion 523 can be a single magnetic pole or multiple magnetic poles arranged at intervals along the circumference of the brake disc 51. Multiple magnetic pole portions 523 can share a single excitation coil 522, or they can be respectively provided with corresponding excitation coils 522. The above different magnetic pole arrangement methods do not affect the basic principle of the winding diameter follower mechanism 6 and the tension swing arm fine adjustment mechanism 8 changing the amount of magnetic shielding in the magnetic circuit action area 55 through the magnetic adjustment mechanism 7.

[0086] It should be noted that, in the above embodiments, for ease of understanding, the structure and working relationship of the diameter follower mechanism 6, the tension swing arm fine-tuning mechanism 8, and the air gap stabilizing structure 9 are described respectively. In actual products, each mechanism can be arranged compactly according to the installation space. For example, the diameter swing arm 63, the compensation cam 67, and the magnetic adjustment slide 71 can be set on one side of the unwinding shaft 2, and the tension swing arm 83 and the fine-tuning linkage 86 can be set on the other side of the unwinding shaft 2, or they can be arranged together on the same side by a reversing linkage. As long as the diameter follower mechanism 6 can make basic adjustments to the magnetic adjustment mechanism 7 according to the change in the diameter of the wrapping tape reel 3, and the tension swing arm fine-tuning mechanism 8 can make fine-tuning corrections to the magnetic adjustment mechanism 7 according to the change in the tension of the wrapping tape 4, the constant tension non-contact braking function of the present invention can be realized.

[0087] In summary, this invention, through the mechanical coordination among the unwinding shaft 2, the non-contact electromagnetic braking assembly 5, the diameter follower mechanism 6, the magnetic adjustment mechanism 7, and the tension swing arm fine-tuning mechanism 8, enables the changes in the diameter of the wrapping reel 3 and the tension changes of the wrapping tape 4 to be directly converted into braking torque adjustment actions. The diameter follower mechanism 6 provides basic braking torque compensation, the tension swing arm fine-tuning mechanism 8 provides real-time braking torque correction, the magnetic adjustment mechanism 7 converts the above mechanical inputs into changes in the amount of magnetic shielding, and the non-contact electromagnetic braking assembly 5 further converts the changes in the amount of magnetic shielding into changes in the braking torque acting on the unwinding shaft 2. Compared to fixed damping, manual adjustment, or ordinary non-contact electromagnetic braking structures, this invention can improve the tension stability of the wrapping tape 4 during high-speed wrapping while reducing friction and wear, and reduce the probability of problems such as wrinkles, loose tape, tape breakage, deviation, pitch changes, and uneven overlap.

[0088] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine, characterized in that, include: The frame, unwinding shaft, non-contact electromagnetic braking assembly, winding diameter follower mechanism, magnetic adjustment mechanism, and tension swing arm fine-tuning mechanism; The unwinding shaft is rotatably mounted on the frame for mounting the wrapping tape reel; The non-contact electromagnetic braking assembly includes a brake disc that rotates synchronously with the unwinding shaft, and an electromagnetic braking unit that is fixed relative to the frame. A non-contact working gap is formed between the electromagnetic braking unit and the brake disc. The electromagnetic braking unit is used to apply braking torque to the brake disc. The magnetic adjustment mechanism is configured corresponding to the magnetic circuit action area between the electromagnetic braking unit and the brake disc. At least a portion of the magnetic adjustment mechanism is movable relative to the magnetic circuit action area to change the amount of magnetic shielding within the magnetic circuit action area, thereby adjusting the braking torque. The winding diameter follower mechanism has a follower end that abuts against the outer periphery of the wrapping tape reel, and a main adjustment output end that is connected to the magnetic adjustment mechanism. The follower end is displaced as the winding diameter of the wrapping tape reel changes, and drives the magnetic adjustment mechanism to adjust the basic braking torque through the main adjustment output end. The tension swing arm fine-tuning mechanism has a tension guide end for winding the wrapping tape and a fine-tuning output end that is connected to the magnetic adjustment mechanism. The tension guide end swings with the change of the wrapping tape tension and drives the magnetic adjustment mechanism to fine-tune the braking torque based on the basic braking torque through the fine-tuning output end.

2. The constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 1, characterized in that, The electromagnetic braking unit includes a magnetic yoke, an excitation coil, and a magnetic pole portion. The excitation coil is disposed on the magnetic yoke, and the magnetic pole portion is disposed facing the brake disc. A non-contact working gap is formed between the magnetic pole portion and the brake disc. The brake disc is fixedly sleeved on the unwinding shaft, or is synchronously rotated and connected to the unwinding shaft through a coupling.

3. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 1, characterized in that, The roll diameter follower mechanism includes a follower roller, a roll diameter swing arm, a swing arm shaft, and a first reset member. The roll diameter swing arm is oscillatingly mounted on the frame via the swing arm shaft. The follower roller is rotatably disposed at one end of the roll diameter swing arm and forms the follower end. The first reset member acts on the roll diameter swing arm to keep the follower roller abutting against the outer periphery of the wrapping reel.

4. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 3, characterized in that, The roll diameter follower mechanism further includes a compensation cam, which is drivenly connected to the roll diameter swing arm. The compensation cam abuts against or is connected to the magnetic adjustment mechanism through a transmission component. The compensation cam has a non-linear profile and is used to convert the oscillation amount of the roll diameter swing arm caused by the change in the roll diameter of the wrapping reel into a non-linear adjustment displacement of the magnetic adjustment mechanism.

5. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 1, characterized in that, The magnetic adjustment mechanism includes a magnetic adjustment slide and a magnetic adjustment component mounted on the magnetic adjustment slide. The magnetic adjustment slide is movably disposed on the frame or the electromagnetic braking unit. The magnetic adjustment component is a magnetic shielding component, which is used to change the amount of magnetic shielding within the magnetic circuit's active area.

6. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 5, characterized in that, The magnetic adjustment slide is provided with a main adjustment input and a fine adjustment input. The main adjustment input is driven to the main adjustment output of the roll diameter follower mechanism, and the fine adjustment input is driven to the fine adjustment output of the tension swing arm fine adjustment mechanism, so that the roll diameter follower mechanism and the tension swing arm fine adjustment mechanism act on the same magnetic adjustment slide from different positions.

7. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 1, characterized in that, The tension swing arm fine-tuning mechanism includes a tension swing arm, a tension guide roller, a tension swing arm pivot, a second reset member, and a fine-tuning link. The tension swing arm is oscillatingly mounted on the frame via the tension swing arm pivot. The tension guide roller is rotatably mounted on the tension swing arm and forms the tension guide end. The wrapping tape is wound around the tension guide roller. The second reset member acts on the tension swing arm. One end of the fine-tuning link is connected to the tension swing arm, and the other end is connected to the magnetic adjustment mechanism.

8. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 7, characterized in that, The tension swing arm fine-tuning mechanism also includes a damper connected between the tension swing arm and the frame to suppress the high-frequency oscillation of the tension swing arm.

9. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 2, characterized in that, The non-contact electromagnetic braking assembly further includes an air gap stabilizing structure, which includes at least one of an axial limiting bearing, a positioning spacer, and an elastic preload member. The air gap stabilizing structure is used to limit the axial movement of the brake disc relative to the magnetic pole portion to maintain the stability of the non-contact working gap; and / or, the electromagnetic braking unit includes a first magnetic pole portion and a second magnetic pole portion located on both sides of the brake disc, respectively. The first magnetic pole portion and the second magnetic pole portion are arranged opposite to each other so that the magnetic attraction forces on both sides of the brake disc are balanced.

10. A constant tension non-contact electromagnetic braking device for a high-speed wrapping machine according to claim 7, characterized in that, The tension swing arm is provided with an eccentric connecting part that is offset from the pivot axis of the tension swing arm. One end of the fine-tuning linkage is hinged to the eccentric connecting part, and the other end is drivenly connected to the magnetic adjustment mechanism through the fine-tuning output end. One end of the second reset member is connected to the tension swing arm, and the other end is connected to the frame or a pre-tightening adjustment seat provided on the frame. When the second reset member is connected to the pre-tightening adjustment seat, the pre-tightening adjustment seat is used to adjust the pre-tightening force of the second reset member to set the tension reference of the tension swing arm fine-tuning mechanism.

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