Circular knitting machine yarn tension adjustment device and method

Abstract

This invention relates to the field of textile machinery technology, and more particularly to a yarn tension adjustment device and method for a circular knitting machine. The device includes a fixed box and a guide roller fixedly connected to the front of the fixed box. A drive motor is fixedly connected to the inner cavity of the fixed box. A speed dynamic compensation adjustment mechanism is provided on the top of the front of the fixed box, and the speed dynamic compensation adjustment mechanism includes an adjustment box fixedly connected to the front of the fixed box. This invention constructs a three-level tension control system through the coordinated operation of the speed dynamic compensation adjustment mechanism, the adaptive magnetic buffer adjustment mechanism, and the tension feedback and limit protection mechanism. This system features feedforward dynamic compensation, instantaneous magnetic buffering, and overload feedback unloading. The three levels of mechanisms respectively address tension fluctuations of different frequencies and amplitudes, enabling the device to adapt to the production of various yarn varieties with different elastic moduli and unwinding characteristics, thus improving the versatility and adaptability of the equipment.

Description

Technical Field

[0001] This invention relates to the field of textile machinery technology, and in particular to a yarn tension adjustment device and method for a circular knitting machine. Background Technology

[0002] Circular knitting machines are core production equipment in the modern knitting industry. They continuously feed yarn to the knitting area via a multi-path yarn feeding system, where it is knitted in loops by needles. They are widely used in the large-scale production of various knitted fabrics. During operation, after unwinding from the yarn bobbin, the yarn passes through a series of paths including a yarn guide, tension regulator, and yarn storer before entering the knitting area. The stability of the yarn tension directly affects the uniformity of loop formation, the consistency of fabric density, and the quality of the fabric surface. Especially with the development of circular knitting machines towards higher speeds and more multiple paths, the yarn feed speed changes frequently, increasing the requirements for tension control precision.

[0003] Existing tension adjustment devices mostly employ spring-loaded mechanical tension discs or single magnetic powder brakes. These devices exhibit significant hysteresis and cannot respond in real-time to sudden tension changes caused by starting, stopping, or speed changes in circular knitting machines. Furthermore, when the yarn experiences instantaneous peak tension due to external factors (such as uneven yarn thickness or passing through knots), rigid or semi-rigid adjustment mechanisms lack effective buffering margins, easily leading to yarn breakage. Simultaneously, existing multi-stage adjustment mechanisms are often independent, lacking a linkage feedback mechanism. If a previous stage of adjustment fails, subsequent stages cannot intervene in time to compensate, resulting in poor overall adjustment accuracy and difficulty meeting the technological requirements of high-end knitted fabrics. Summary of the Invention

[0004] The purpose of this invention is to provide a yarn tension adjustment device and method for a circular knitting machine. By coordinating a dynamic speed compensation adjustment mechanism, an adaptive magnetic buffer adjustment mechanism, and a tension feedback limit protection mechanism, the invention solves the problems of lagging tension adjustment response, fixed buffer capacity and lack of adaptive function, and abnormal feedback protection mechanism in the prior art.

[0005] The technical solution of the present invention is as follows: a yarn tension adjustment device and method for a circular knitting machine, comprising a fixed box and a guide roller fixedly connected to the front of the fixed box, wherein a drive motor is fixedly connected to the inner cavity of the fixed box; a speed dynamic compensation adjustment mechanism is provided at the top of the front of the fixed box, the speed dynamic compensation adjustment mechanism comprising an adjustment box fixedly connected to the front of the fixed box, a swing rod fixedly connected to the front of the fixed box, and an adjustment roller provided at one end of the swing rod; an adaptive magnetic suction buffer adjustment mechanism is provided on the bottom left side of the front of the fixed box, the adaptive magnetic suction buffer adjustment mechanism comprising a rotating cylinder rotatably connected to the inner cavity of the fixed box via a bearing seat, and a fixed disk fixedly connected to one end of the rotating cylinder; a tension feedback and limit protection mechanism is provided on the bottom right side of the front of the fixed box, the tension feedback and limit protection mechanism comprising a groove formed on the front of the fixed box, a slider slidably connected to the inner cavity of the groove, and a pressure roller rotatably connected to the slider via a bearing seat.

[0006] Preferably, the speed dynamic compensation adjustment mechanism further includes a reciprocating drive component disposed in the inner cavity of the adjustment box, a piston cylinder fixedly connected to the front of the fixed box, a piston rod disposed in the inner cavity of the piston cylinder, a drive sleeve fixedly connected to one end of the piston rod, an air inlet pipe opened at the top of the piston cylinder, an air outlet pipe opened at the bottom of the piston cylinder, and a pneumatic control valve disposed on the surface of the air outlet pipe. The center of the swing rod is rotatably connected to the front of the fixed box through a rotating seat.

[0007] Preferably, the reciprocating drive component includes a turntable fixedly connected to the output shaft of the drive motor, a guide post fixedly and eccentrically connected to the surface of the turntable, a sliding frame slidably connected to the surface of the guide post, a slide rod fixedly connected to the bottom of the sliding frame, a sliding sleeve slidably connected to the surface of the slide rod, and a drive rod fixedly connected to the bottom of the sliding sleeve. The inner cavity of the drive sleeve is provided with balls, and the drive sleeve is fitted onto the surface of the drive rod.

[0008] Preferably, one end of the drive rod extends through to the outside of the adjustment box and is fixedly connected to a roller. The roller abuts against the top of one end of the swing rod. A sliding hole is provided on the surface of the sliding frame, and a limit rod is slidably connected to the inner cavity of the sliding hole. The two ends of the limit rod are fixedly connected to the top and bottom of the inner cavity of the adjustment box, respectively.

[0009] Preferably, the adaptive magnetic buffer adjustment mechanism further includes a fixed groove on one side of the fixed plate, a first magnetic plate slidably connected to the fixed groove, a fixed roller fixedly connected to one side of the first magnetic plate, a second magnetic plate disposed on the other side of the first magnetic plate, a support rod movably connected to one side of the second magnetic plate, and a fixed shaft movably connected to the other end of the support rod.

[0010] Preferably, the first magnetic plate and the second magnetic plate are designed with magnetic pole repulsion, the number of fixed rollers is six and they are arranged in a circular array, and a synchronization component is connected between the output shaft of the drive motor and the rotating drum.

[0011] Preferably, the tension feedback and limit protection mechanism further includes a first spring fixedly connected to the inner cavity of the slide groove, a guide rod fixedly connected to the inner cavity of the fixed box, a push plate slidably connected to the surface of the guide rod, a drive block fixedly connected to one side of the push plate, a drive wheel fixedly connected to the back of the slider, and a second spring sleeved on the surface of the guide rod.

[0012] Preferably, the other end of the first spring is fixedly connected to the bottom of the slider, one end of the second spring is fixedly connected to the inner cavity of the fixed box, the other end of the second spring is fixedly connected to one side of the push plate, and the drive wheel abuts against the inclined surface of the drive block.

[0013] Preferably, there are two guide rollers, located on the left and right sides of the front of the fixing box, respectively, and a control panel is provided on the left side of the fixing box.

[0014] A method for adjusting the yarn tension adjustment device of a circular knitting machine includes the following steps: A: The yarn is sequentially passed around the guide roller on the left side of the front of the fixed box, the adjusting roller of the speed compensation mechanism, the six fixed rollers of the adaptive adjustment mechanism, the pressure roller of the limit adjustment mechanism, and the guide roller on the right side of the front of the fixed box. B: Start the drive motor. The drive motor drives the rotating drum and fixed plate to rotate through the synchronization component. The fixed roller moves in a circle with the fixed plate. At this time, the gas filling device (the other end of the air inlet pipe is connected to the gas filling device, which is a centrifugal air pump coaxially fixed to the power shaft of the large circular knitting machine's wire feeding roller) injects gas into the piston cylinder. The piston rod is located on the right side of the piston cylinder. The drive sleeve drives the drive rod to the initial low position. The swing amplitude of the swing rod is at the preset minimum value. At the same time, the first spring and the second spring support the pressure roller together, so that the drive wheel and the inclined surface of the drive block are in the initial separation state. The second magnetic plate is located in the initial position away from the center of the fixed plate. The system enters the standby preparation state. C: The circular knitting machine starts operating at high speed. The power shaft of the yarn feed roller drives the air supply equipment to rotate synchronously. When the yarn feed rate increases, the amount of air entering the piston cylinder from the air supply equipment is greater than the amount of air discharged from the outlet pipe under the limitation of the air pressure control valve. The pressure inside the piston cylinder increases, pushing the piston rod to the left, which in turn drives the drive sleeve and the internal balls to the left. As the drive rod continues to move up and down under the drive of the reciprocating drive component, the leftward movement of the drive sleeve changes the relative contact position between the roller and the drive rod (i.e., changes the lever arm length), causing the swing rod to swing back and forth at a larger angle around the rotating seat. The swing amplitude of the adjusting roller increases accordingly, thereby compensating for the yarn tension fluctuation caused by the increase in the yarn feed rate. When the yarn feed rate decreases, the amount of air entering decreases, and the piston moves to the right under the action of the pressure difference. The swing amplitude of the adjusting roller decreases accordingly, achieving reverse compensation. D: The yarn is driven by high-speed friction on the surface of the fixed roller. When the yarn tension increases instantaneously, the drag force exerted by the yarn on the fixed roller increases, which overcomes the initial magnetic repulsion between the first magnetic plate and the second magnetic plate, forcing the first magnetic plate to move inward along the fixed groove. Since the magnetic poles of the first magnetic plate and the second magnetic plate repel each other, the instantaneous tension peak is absorbed. The first magnetic plates corresponding to the six fixed rollers respond independently and make fine adjustments according to the tension of the yarn segments they contact, so as to achieve distributed adaptive balance of tension and avoid weaving defects caused by uneven local tension. E: When the yarn still has excessive residual tension after the above two-stage adjustment (i.e., the yarn is overly taut), this tension will press down on the pressure roller. After the pressure roller is subjected to force, it drives the slider to move down along the slide groove through the bearing seat, compressing the first spring. The drive wheel on the back of the slider also descends, squeezing the drive block that abuts against its inclined surface, forcing the push plate to move horizontally along the guide rod to the outside of the fixed box, compressing the second spring. The outward movement of the push plate pulls the second magnetic plate towards the center of the fixed plate through the fixed shaft and support rod, increasing the magnetic repulsion distance between the second magnetic plate and the first magnetic plate (i.e., increasing the buffer stroke space of the first magnetic plate), thereby reducing the constraint stiffness on the yarn, automatically releasing the excessive tension, and preventing the yarn from breaking. When the tension returns to normal, the first spring and the second spring reset, and each mechanism returns to its initial position.

[0015] The beneficial effects of this invention are as follows: 1. This invention constructs a three-level tension control system by coordinating a rate dynamic compensation adjustment mechanism, an adaptive magnetic suction buffer adjustment mechanism, and a tension feedback and limit protection mechanism. The system consists of feedforward dynamic compensation, instantaneous magnetic suction buffer, and overload feedback unloading. The three-level mechanism performs layered processing for tension fluctuations of different frequencies and amplitudes, enabling the device to adapt to the production of various yarn varieties with different elastic moduli and unwinding characteristics, thereby improving the versatility and adaptability of the equipment.

[0016] 2. This invention, by setting up a dynamic rate compensation adjustment mechanism, utilizes the coaxial linkage between the air supply equipment and the power shaft of the large circular knitting machine's wire feeding roller to make the air intake in the piston cylinder change synchronously with the wire feeding rate. Then, the piston rod drives the drive sleeve to slide along the drive rod to change the lever arm length, thereby realizing real-time dynamic adjustment of the swing amplitude of the adjustment roller. This makes the tension compensation amount match the change in wire feeding rate, effectively solving the problem of large tension fluctuations during acceleration and deceleration, and improving the tension stability during high-speed weaving.

[0017] 3. This invention, by setting an adaptive magnetic suction buffer adjustment mechanism, replaces the traditional spring buffer with a magnetic buffering method in which the first and second magnetic plates repel each other. It utilizes the nonlinear characteristics of magnetic repulsion to achieve efficient absorption of instantaneous tension spikes. At the same time, the six fixed rollers respond independently and can perform distributed fine-tuning according to the tension differences at different positions in the yarn width direction, avoiding local tension concentration and improving the adaptability to instantaneous tension impacts. In addition, by setting a tension feedback and limit protection mechanism, when the yarn tension is continuously too high, the pressure roller is pressed down and moves outward through the cooperation of the drive wheel and the inclined surface of the drive block. Then, the support rod pulls the second magnetic plate to move towards the center of the fixed plate, increasing the buffering stroke of the first magnetic plate and automatically reducing the constraint stiffness on the yarn to achieve unloading protection, preventing the yarn from breaking or being damaged due to excessive stretching, and effectively ensuring yarn quality. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0019] Figure 1 A perspective view of a yarn tension adjustment device and method for a circular knitting machine; Figure 2 This is a schematic diagram of the internal structure of the regulating box in a yarn tension regulating device and method for a large circular knitting machine. Figure 3 This is a rear sectional view of the fixed box in a yarn tension adjustment device and method for a circular knitting machine. Figure 4 This is a diagram showing the connection between the rotary drum and the pressure roller in a yarn tension adjustment device and method for a circular knitting machine. Figure 5 This is a schematic diagram of the tension feedback and limit protection mechanism in a yarn tension adjustment device and method for a circular knitting machine; Figure 6 This is a diagram showing the assembly of a first magnetic plate, a fixed roller, a second magnetic plate, a support rod, and a fixed shaft in a yarn tension adjustment device and method for a circular knitting machine. Figure 7 This is a schematic diagram of an adaptive magnetic buffer adjustment mechanism in a yarn tension adjustment device and method for a circular knitting machine. Figure 8 This is a schematic diagram of the cooperation between the piston cylinder and the reciprocating drive component in a yarn tension adjustment device and method for a large circular knitting machine. Figure 9 A cross-sectional view of the piston cylinder in a yarn tension regulating device and method for a circular knitting machine; Figure 10 This is a schematic diagram of a reciprocating drive component in a yarn tension adjustment device and method for a circular knitting machine. Figure 11This is a diagram showing the fit between the drive sleeve and the drive rod in a yarn tension adjustment device and method for a circular knitting machine.

[0020] Explanation of reference numerals in the attached drawings: 1. Fixed box; 2. Guide roller; 3. Drive motor; 4. Dynamic speed compensation adjustment mechanism; 41. Adjustment box; 42. Swing rod; 43. Adjustment roller; 44. Reciprocating drive component; 441. Turntable; 442. Guide column; 443. Sliding frame; 444. Slide rod; 445. Sliding sleeve; 446. Drive rod; 45. Piston cylinder; 46. Piston rod; 47. Drive sleeve; 48. Inlet pipe; 49. Outlet pipe; 410. Air pressure control valve; 5. Adaptive magnetic buffer. Adjustment mechanism; 51. Rotary drum; 52. Fixed disc; 53. Fixed groove; 54. First magnetic plate; 55. Fixed roller; 56. Second magnetic plate; 57. Support rod; 58. Fixed shaft; 6. Tension feedback and limit protection mechanism; 61. Slide groove; 62. Slider; 63. Pressure roller; 64. First spring; 65. Guide rod; 66. Push plate; 67. Drive block; 68. Drive wheel; 69. Second spring; 7. Ball bearing; 8. Roller; 9. Limit rod; 10. Synchronization assembly; 11. Control panel. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] Example 1

[0023] Please see Figures 1-11 This is the first embodiment of the present invention, which provides a yarn tension adjustment device and method for a circular knitting machine. The device includes a fixed box 1 and a guide roller 2 fixedly connected to the front of the fixed box 1. A drive motor 3 is fixedly connected to the inner cavity of the fixed box 1. A speed dynamic compensation adjustment mechanism 4 is provided at the top of the front of the fixed box 1. The speed dynamic compensation adjustment mechanism 4 includes an adjustment box 41 fixedly connected to the front of the fixed box 1, a swing rod 42 fixedly connected to the front of the fixed box 1, and an adjustment roller 43 at one end of the swing rod 42. An adaptive magnetic suction buffer adjustment mechanism 5 is provided on the bottom left side of the front of the fixed box 1. The adaptive magnetic suction buffer adjustment mechanism 5 includes a rotating cylinder 51 rotatably connected to the inner cavity of the fixed box 1 via a bearing seat, and a fixed disk 52 fixedly connected to one end of the rotating cylinder 51. A tension feedback and limit protection mechanism 6 is provided on the bottom right side of the front of the fixed box 1. The tension feedback and limit protection mechanism 6 includes a groove 61 formed on the front of the fixed box 1, a slider 62 slidably connected to the inner cavity of the groove 61, and a pressure roller 63 rotatably connected to the slider 62 via a bearing seat.

[0024] The center of the swing rod 42 is rotatably connected to the front of the fixed box 1 via a rotating seat, so that the swing rod 42 can swing back and forth in the vertical plane around the rotating seat. The adjusting roller 43 is set at the far end of the swing rod 42 and moves up and down with the swing rod 42, thereby changing the pressure on the yarn to achieve tension adjustment. The output shaft of the drive motor 3 is connected to the rotating drum 51 through the synchronization component 10 (the synchronization component 10 can be a synchronous belt drive mechanism). When the drive motor 3 rotates, it drives the rotating drum 51 and the fixed plate 52 to rotate synchronously. The slide groove 61 extends in the vertical direction, and the slider 62 is constrained in the slide groove 61 and can slide back and forth in the vertical direction. The pressure roller 63 moves up and down with the slider 62.

[0025] The yarn passes sequentially around the guide roller 2 on the left side of the front of the fixed box 1, the adjusting roller 43 of the speed dynamic compensation adjustment mechanism 4, the six fixed rollers 55 of the adaptive magnetic buffer adjustment mechanism 5, the pressure roller 63 of the tension feedback and limit protection mechanism 6, and the guide roller 2 on the right side of the front of the fixed box 1, forming a complete yarn path. The yarn tension is dynamically compensated, magnetically buffered, and unloaded by the above three mechanisms.

[0026] The rate dynamic compensation adjustment mechanism 4 acts as a feedforward link to actively compensate for large-range, low-frequency changes in wire feed rate. The adaptive magnetic buffer adjustment mechanism 5 acts as an intermediate buffer link to passively absorb instantaneous tension spikes in the medium and high frequencies. The tension feedback and limit protection mechanism 6 acts as a safety protection link, intervening only when the residual tension continuously exceeds the threshold. Overload protection is achieved by increasing the buffer stroke. The three-level mechanisms perform layered processing for tension fluctuations of different frequencies and amplitudes, and together they construct a complete tension control system.

[0027] During operation, the yarn is first threaded along the path described above. Then, the drive motor 3 and the main unit of the circular knitting machine are started. The drive motor 3 drives the rotating drum 51 and the fixed plate 52 of the adaptive magnetic buffer adjustment mechanism 5 to rotate through the synchronization component 10. This causes the fixed roller 55 to move in a circular motion with the fixed plate 52, providing continuous feeding assistance for the yarn. At the same time, the speed dynamic compensation adjustment mechanism 4 dynamically adjusts the swing amplitude of the adjustment roller 43 according to the real-time feeding rate of the circular knitting machine's feeding roller, providing feedforward compensation for tension fluctuations caused by changes in the feeding rate. When the yarn encounters a momentary tension peak during high-speed operation, the magnetic buffer structure in the adaptive magnetic buffer adjustment mechanism 5 absorbs the impact energy. When the yarn tension continuously exceeds the safety threshold, the tension feedback and limit protection mechanism 6 is activated, increasing the buffer stroke to achieve unloading protection, thereby ensuring that the yarn enters the weaving area under stable tension.

[0028] Example 2

[0029] Please see Figures 1-11 This is the second embodiment of the present invention, which is based on the previous embodiment.

[0030] Specifically, the speed dynamic compensation adjustment mechanism 4 also includes a reciprocating drive component 44 disposed in the inner cavity of the adjustment box 41, a piston cylinder 45 fixedly connected to the front of the fixed box 1, a piston rod 46 disposed in the inner cavity of the piston cylinder 45, a drive sleeve 47 fixedly connected to one end of the piston rod 46, an air inlet pipe 48 opened at the top of the piston cylinder 45, an air outlet pipe 49 opened at the bottom of the piston cylinder 45, and a pneumatic control valve 410 disposed on the surface of the air outlet pipe 49. The center of the swing rod 42 is rotatably connected to the front of the fixed box 1 through a rotating seat. The reciprocating drive component 44 includes a turntable 441 fixedly connected to the output shaft of the drive motor 3, and a guide eccentrically fixedly connected to the surface of the turntable 441. The guide post 442, the sliding frame 443 which is slidably connected to the surface of the guide post 442, the sliding rod 444 which is fixedly connected to the bottom of the sliding frame 443, the sliding sleeve 445 which is slidably connected to the surface of the sliding rod 444, and the drive rod 446 which is fixedly connected to the bottom of the sliding sleeve 445. The inner cavity of the drive sleeve 47 is provided with a ball 7. The drive sleeve 47 is fitted on the surface of the drive rod 446. One end of the drive rod 446 extends through to the outside of the adjustment box 41 and is fixedly connected to a roller 8. The roller 8 abuts against the top of one end of the swing rod 42. The surface of the sliding frame 443 is provided with a sliding hole, and the inner cavity of the sliding hole is slidably connected to a limit rod 9. The two ends of the limit rod 9 are fixedly connected to the top and bottom of the inner cavity of the adjustment box 41, respectively.

[0031] The other end of the air inlet pipe 48 is connected to an air filling device (not shown in the figure, which is prior art). The air filling device is a centrifugal air pump coaxially fixed to the power shaft of the wire feeding roller of the large circular knitting machine. When the wire feeding speed increases, the air filling capacity of the air filling device increases synchronously, and vice versa. The drive rod 446 passes through the drive sleeve 47 and the two form a rolling contact fit through the ball bearing 7 to reduce the friction force when sliding relative to each other. When the piston rod 46 moves left and right with the change of air pressure in the piston cylinder 45, the drive sleeve 47 drives the relative contact position between it and the drive rod 446 to move synchronously, thereby changing the effective lever arm length of the drive rod 446.

[0032] The sliding frame 443 has a sliding hole extending vertically on its surface. A limiting rod 9 is slidably connected to the inner cavity of the sliding hole. The two ends of the limiting rod 9 are fixedly connected to the top and bottom of the inner cavity of the regulating box 41, respectively. The sliding frame 443 is constrained to only reciprocate in the vertical direction by the cooperation of the limiting rod 9 and the sliding hole. The sliding sleeve 445 is fixedly connected to the bottom of the inner cavity of the regulating box 41. One end of the drive rod 446 passes through the bottom of the regulating box 41 and extends to the outside of the regulating box 41. A roller 8 is fixedly connected to the extended end of the drive rod 446. The roller 8 abuts against the top of one end of the swing rod 42.

[0033] The drive motor 3 drives the guide column 442 to rotate eccentrically via the turntable 441. The guide column 442 slides in the sliding hole of the sliding frame 443 and drives the sliding frame 443 to reciprocate in the vertical direction. The sliding frame 443 drives the drive rod 446 to reciprocate up and down via the slide rod 444 and the slide sleeve 445. The roller 8 at the end of the drive rod 446 periodically presses down on one end of the swing rod 42, causing the swing rod 42 to reciprocate around the rotating seat. The adjusting roller 43 swings up and down accordingly. The air supply device changes the air pressure in the piston cylinder 45 according to the yarn feeding rate, pushing the piston rod 46 and the drive sleeve 47 to move axially along the drive rod 446. This changes the relative contact position between the roller 8 and the drive rod 446, i.e., changes the lever arm length, so that the swing amplitude of the swing rod 42 changes synchronously with the yarn feeding rate, thereby realizing dynamic compensation for yarn tension.

[0034] In use, when the wire feeding rate of the large circular knitting machine increases, the amount of air entering the piston cylinder 45 from the air filling device is greater than the amount of air discharged from the air outlet pipe 49 under the limitation of the air pressure control valve 410. The pressure inside the piston cylinder 45 increases, pushing the piston rod 46 to move to the left. The drive sleeve 47 drives the relative position of the drive rod 446 to slide to the left, increasing the effective driving length of the drive rod 446. The driving stroke of the roller 8 on the swing rod 42 is amplified, the swing angle of the swing rod 42 increases, the swing amplitude of the adjusting roller 43 increases accordingly, and the tension compensation increases. Conversely, when the wire feeding rate decreases, the piston rod 46 moves to the right, and the swing amplitude of the adjusting roller 43 decreases, achieving reverse compensation.

[0035] Example 3

[0036] Please see Figures 1-11 This is the third embodiment of the present invention, which is based on the first two embodiments.

[0037] Specifically, the adaptive magnetic suction buffer adjustment mechanism 5 also includes a fixed groove 53 on one side of the fixed plate 52, a first magnetic plate 54 slidably connected to the fixed groove 53, a fixed roller 55 fixedly connected to one side of the first magnetic plate 54, a second magnetic plate 56 set on the other side of the first magnetic plate 54, a support rod 57 movably connected to one side of the second magnetic plate 56, and a fixed shaft 58 movably connected to the other end of the support rod 57. The first magnetic plate 54 and the second magnetic plate 56 are designed with magnetic pole repulsion. There are six fixed rollers 55 arranged in a circular array. A synchronization component 10 is connected between the output shaft of the drive motor 3 and the rotating drum 51.

[0038] The first magnetic plate 54 and the second magnetic plate 56 are arranged with their same poles facing each other and their magnetic poles repel each other. That is, the side of the first magnetic plate 54 facing the second magnetic plate 56 and the side of the second magnetic plate 56 facing the first magnetic plate 54 have the same magnetic pole (e.g., both are N poles or both are S poles). The principle of like poles repulsion is used to provide elastic buffering force. The drive motor 3 is connected to the rotating drum 51 through the synchronization component 10 and drives the fixed disk 52 to rotate. The six fixed rollers 55 move in a circle with the fixed disk 52. Each fixed roller 55 independently achieves distributed adaptive buffering of yarn tension through the magnetic repulsion between its corresponding first magnetic plate 54 and second magnetic plate 56.

[0039] When the yarn passes over the surface of the fixed roller 55, the yarn applies radial pressure to the fixed roller 55. When the yarn tension increases instantaneously, this pressure overcomes the magnetic repulsion between the first magnetic plate 54 and the second magnetic plate 56, pushing the first magnetic plate 54 to slide along the fixed groove 53 toward the center of the fixed disk 52. The distance between the first magnetic plate 54 and the second magnetic plate 56 decreases, and the magnetic repulsion increases sharply (the magnetic repulsion is inversely proportional to the square of the distance), thereby efficiently absorbing tension spikes.

[0040] Since the six fixed rollers 55 are independently slidably engaged with the fixed grooves 53 through the corresponding first magnetic plates 54, each fixed roller 55 can respond independently according to the different tension conditions of the yarn segments it contacts, realizing distributed adaptive adjustment. When the tension peak disappears, the first magnetic plate 54 is reset under the action of magnetic repulsion. Since the magnetic repulsion has nonlinear characteristics (the closer the distance, the greater the repulsion), it can effectively prevent the first magnetic plate 54 from colliding with the second magnetic plate 56, and at the same time provide a gradual buffering effect, avoiding the resonance and fatigue failure problems that may occur in traditional spring buffers.

[0041] Example 4

[0042] Please see Figures 1-11 This is the fourth embodiment of the present invention, which is based on the first three embodiments.

[0043] Specifically, the tension feedback and limit protection mechanism 6 also includes a first spring 64 fixedly connected to the inner cavity of the slide 61, a guide rod 65 fixedly connected to the inner cavity of the fixed box 1, a push plate 66 slidably connected to the surface of the guide rod 65, a drive block 67 fixedly connected to one side of the push plate 66, a drive wheel 68 fixedly connected to the back of the slider 62, and a second spring 69 sleeved on the surface of the guide rod 65. The other end of the first spring 64 is fixedly connected to the bottom of the slider 62, one end of the second spring 69 is fixedly connected to the inner cavity of the fixed box 1, and the other end of the second spring 69 is fixedly connected to one side of the push plate 66. The drive wheel 68 abuts against the inclined surface of the drive block 67. There are two guide rollers 2, which are located on the left and right sides of the front of the fixed box 1, respectively. A control panel 11 is provided on the left side of the fixed box 1.

[0044] The first spring 64 provides an upward elastic support force for the slider 62. The push plate 66 is sleeved on the surface of the guide rod 65 and can slide horizontally along the guide rod 65. The second spring 69 provides a restoring force for the push plate 66 toward the inside of the fixed box 1 (i.e., toward the fixed disk 52). The outer edge of the drive wheel 68 abuts against the inclined surface of the drive block 67. When the slider 62 is pressed down, the drive wheel 68 squeezes the inclined surface of the drive block 67, forcing the push plate 66 to move horizontally along the guide rod 65 away from the fixed disk 52 and compressing the second spring 69.

[0045] After the yarn has been adjusted by the speed dynamic compensation adjustment mechanism 4 and the adaptive magnetic buffer adjustment mechanism 5, if there is still residual tension exceeding the preset threshold, the tension will press down on the pressure roller 63. The pressure roller 63 will drive the slider 62 to move down along the slide groove 61 through the bearing seat and compress the first spring 64. The drive wheel 68 on the back of the slider 62 will move down accordingly. The outer edge of the drive wheel 68 will press against the inclined surface of the drive block 67, converting the vertical displacement into a horizontal displacement, forcing the push plate 66 to move horizontally along the guide rod 65 to the outside of the fixed box 1 (i.e., away from the fixed plate 52) and compress the second spring 69.

[0046] The outward movement of the push plate 66 pulls the support rod 57 via the fixed shaft 58. The support rod 57 then pulls the second magnetic plate 56 towards the center of the fixed disk 52, increasing the distance between the second magnetic plate 56 and the first magnetic plate 54. This reduces the magnetic repulsion force and increases the sliding stroke of the first magnetic plate 54, which in turn increases the retractable buffer space of the fixed roller 55. The constraint force on the yarn decreases, achieving automatic tension unloading. When the yarn tension drops to the normal range, the first spring 64 pushes the slider 62 upward to reset, and the second spring 69 pushes the push plate 66 inward to reset. The second magnetic plate 56 returns to its initial position away from the center, the magnetic repulsion gap returns to its minimum value, and the device returns to normal operation.

[0047] A method for adjusting the yarn tension adjustment device of a circular knitting machine includes the following steps: A: The yarn is passed in sequence around the guide roller 2 on the left side of the front of the fixed box 1, the adjusting roller 43 of the speed compensation mechanism, the six fixed rollers 55 of the adaptive adjustment mechanism, the pressure roller 63 of the limit adjustment mechanism, and the guide roller 2 on the right side of the front of the fixed box 1. B: Start the drive motor 3. The drive motor 3 drives the rotating drum 51 and the fixed disk 52 to rotate through the synchronization component 10. The fixed roller 55 moves in a circle with the fixed disk 52. At this time, the gas filling device (the other end of the air inlet pipe 48 is connected to the gas filling device, which is a centrifugal air pump coaxially fixed to the power shaft of the large circular knitting machine's wire feeding roller) injects gas into the piston cylinder 45. The piston rod 46 is located on the right side of the piston cylinder 45. The drive sleeve 47 drives the drive rod 446 to the initial low position. The swing amplitude of the swing rod 42 is at the preset minimum value. At the same time, the first spring 64 and the second spring 69 jointly support the pressure roller 63, so that the inclined surface of the drive wheel 68 and the drive block 67 is in the initial separation state. The second magnetic plate 56 is located in the initial position away from the center of the fixed disk 52. The system enters the standby preparation state. C: The circular knitting machine starts operating at high speed. The power shaft of the yarn feeding roller drives the air supply equipment to rotate synchronously. When the yarn feeding rate increases, the amount of air entering the piston cylinder 45 from the air supply equipment is greater than the amount of air discharged from the air outlet pipe 49 under the limitation of the air pressure control valve 410. The pressure inside the piston cylinder 45 increases, pushing the piston rod 46 to the left, which in turn drives the drive sleeve 47 and the internal ball bearings 7 to the left. As the drive rod 446 continues to move up and down under the drive of the reciprocating drive component 44, the leftward movement of the drive sleeve 47 changes the relative contact position between the roller 8 and the drive rod 446 (i.e., changes the lever arm length), causing the swing rod 42 to swing back and forth at a larger angle around the rotating seat. The swing amplitude of the adjusting roller 43 increases accordingly, thereby compensating for the yarn tension fluctuation caused by the increase in the yarn feeding rate. When the yarn feeding rate decreases, the amount of air entering decreases, and the piston moves to the right under the action of the pressure difference. The swing amplitude of the adjusting roller 43 decreases accordingly, achieving reverse compensation. D: The yarn is driven by high-speed friction on the surface of the fixed roller 55. When the yarn tension increases instantaneously, the drag force exerted by the yarn on the fixed roller 55 increases, which overcomes the initial magnetic repulsion between the first magnetic plate 54 and the second magnetic plate 56, forcing the first magnetic plate 54 to move inward along the fixed groove 53. Since the magnetic poles of the first magnetic plate 54 and the second magnetic plate 56 repel each other, the instantaneous tension peak is absorbed. The first magnetic plate 54 corresponding to the six fixed rollers 55 responds independently and makes fine adjustments according to the tension of the yarn segment they are in contact with, so as to achieve distributed adaptive balance of tension and avoid weaving defects caused by uneven local tension. E: When the yarn still has excessive residual tension after the above two-stage adjustment (i.e., the yarn is overly taut), this tension will press down on the pressure roller 63. After the pressure roller 63 is under force, it drives the slider 62 to move down along the slide groove 61 through the bearing seat, compressing the first spring 64. The drive wheel 68 on the back of the slider 62 will then descend, squeezing the drive block 67 that is in contact with its inclined surface. This forces the push plate 66 to move horizontally outward along the guide rod 65 to the outside of the fixed box 1, compressing the second spring 69. The outward movement of the push plate 66 pulls the second magnetic plate 56 towards the center of the fixed disk 52 through the fixed shaft 58 and the support rod 57, increasing the magnetic repulsion distance between the second magnetic plate 56 and the first magnetic plate 54 (i.e., increasing the buffer stroke space of the first magnetic plate 54). This reduces the constraint stiffness on the yarn, automatically releases the excessive tension, and prevents the yarn from breaking. When the tension returns to normal, the first spring 64 and the second spring 69 reset, and each mechanism returns to its initial position.

[0048] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A yarn tension adjusting device for a circular knitting machine, comprising a fixed box (1) and a guide roller (2) fixedly connected to the front of the fixed box (1), characterized in that: The drive motor (3) is fixedly connected to the inner cavity of the fixed box (1); The fixed box (1) is provided with a speed dynamic compensation adjustment mechanism (4) on the top front. The speed dynamic compensation adjustment mechanism (4) includes an adjustment box (41) fixedly connected to the front of the fixed box (1), a swing rod (42) fixedly connected to the front of the fixed box (1), and an adjustment roller (43) provided at one end of the swing rod (42). The speed dynamic compensation adjustment mechanism (4) also includes a reciprocating drive component (44) provided in the cavity of the adjustment box (41), a piston cylinder (45) fixedly connected to the front of the fixed box (1), a piston rod (46) provided in the cavity of the piston cylinder (45), a drive sleeve (47) fixedly connected to one end of the piston rod (46), an air inlet pipe (48) opened at the top of the piston cylinder (45), an air outlet pipe (49) opened at the bottom of the piston cylinder (45), and a pneumatic control valve (410) provided on the surface of the air outlet pipe (49). The center of the swing rod (42) is rotatably connected to the front of the fixed box (1) through a rotating seat. An adaptive magnetic suction buffer adjustment mechanism (5) is provided on the bottom left side of the front of the fixed box (1). The adaptive magnetic suction buffer adjustment mechanism (5) includes a rotating cylinder (51) that is rotatably connected to the inner cavity of the fixed box (1) through a bearing seat, and a fixed disk (52) that is fixedly connected to one end of the rotating cylinder (51). The fixed box (1) is provided with a tension feedback and limit protection mechanism (6) on the bottom right side of the front. The tension feedback and limit protection mechanism (6) includes a slide groove (61) opened on the front of the fixed box (1), a slider (62) slidably connected to the inner cavity of the slide groove (61), and a pressure roller (63) rotatably connected to the slider (62) through a bearing seat.

2. The yarn tension adjusting device for a large circular knitting machine according to claim 1, characterized in that: The reciprocating drive component (44) includes a turntable (441) fixedly connected to the output shaft of the drive motor (3), a guide post (442) fixedly connected to the surface of the turntable (441) eccentrically, a sliding frame (443) slidably connected to the surface of the guide post (442), a sliding rod (444) fixedly connected to the bottom of the sliding frame (443), a sliding sleeve (445) slidably connected to the surface of the sliding rod (444), and a drive rod (446) fixedly connected to the bottom of the sliding sleeve (445). The inner cavity of the drive sleeve (47) is provided with a ball (7), and the drive sleeve (47) is sleeved on the surface of the drive rod (446).

3. The yarn tension adjusting device for a large circular knitting machine according to claim 2, characterized in that: One end of the drive rod (446) extends through to the outside of the regulating box (41) and is fixedly connected to a roller (8). The roller (8) abuts against the top of one end of the swing rod (42). The sliding frame (443) has a sliding hole on its surface, and a limit rod (9) is slidably connected to the inner cavity of the sliding hole. The two ends of the limit rod (9) are fixedly connected to the top and bottom of the inner cavity of the regulating box (41) respectively.

4. The yarn tension adjusting device for a circular knitting machine according to claim 1, characterized in that: The adaptive magnetic suction buffer adjustment mechanism (5) further includes a fixed groove (53) opened on one side of the fixed plate (52), a first magnetic plate (54) slidably connected to the fixed groove (53), a fixed roller (55) fixedly connected to one side of the first magnetic plate (54), a second magnetic plate (56) set on the other side of the first magnetic plate (54), a support rod (57) movably connected to one side of the second magnetic plate (56), and a fixed shaft (58) movably connected to the other end of the support rod (57).

5. The yarn tension adjusting device for a circular knitting machine according to claim 4, characterized in that: The first magnetic plate (54) and the second magnetic plate (56) are designed with magnetic pole repulsion. There are six fixed rollers (55) arranged in a circular array. The output shaft of the drive motor (3) is connected to the rotating drum (51) by a synchronous component (10).

6. The yarn tension adjusting device for a circular knitting machine according to claim 1, characterized in that: The tension feedback and limit protection mechanism (6) further includes a first spring (64) fixedly connected to the inner cavity of the slide (61), a guide rod (65) fixedly connected to the inner cavity of the fixed box (1), a push plate (66) slidably connected to the surface of the guide rod (65), a drive block (67) fixedly connected to one side of the push plate (66), a drive wheel (68) fixedly connected to the back of the slider (62), and a second spring (69) sleeved on the surface of the guide rod (65).

7. The yarn tension adjusting device for a circular knitting machine according to claim 6, characterized in that: The other end of the first spring (64) is fixedly connected to the bottom of the slider (62), one end of the second spring (69) is fixedly connected to the inner cavity of the fixed box (1), the other end of the second spring (69) is fixedly connected to one side of the push plate (66), and the drive wheel (68) abuts against the inclined surface of the drive block (67).

8. The yarn tension adjusting device for a circular knitting machine according to claim 1, characterized in that: There are two guide rollers (2), which are located on the left and right sides of the front of the fixed box (1), respectively. The left side of the fixed box (1) is equipped with a control panel (11).

9. A method for adjusting the yarn tension adjustment device of a circular knitting machine, based on the yarn tension adjustment device of a circular knitting machine according to any one of claims 1-8, characterized in that: Includes the following steps: A: The yarn is passed in sequence around the guide roller (2) on the left side of the front of the fixed box (1), the adjusting roller (43) of the speed compensation mechanism, the six fixed rollers (55) of the adaptive adjustment mechanism, the pressure roller (63) of the limit adjustment mechanism, and the guide roller (2) on the right side of the front of the fixed box (1). B: Start the drive motor (3). The drive motor (3) drives the rotating drum (51) and the fixed disk (52) to rotate through the synchronization component (10). The fixed roller (55) moves in a circle with the fixed disk (52). At this time, the gas filling device, which is coaxially fixed with the power shaft of the large circular machine wire feeding roller, injects gas into the piston cylinder (45). The piston rod (46) is located on the right side of the piston cylinder (45). The drive sleeve (47) drives the drive rod (446) to be in the initial low position. The swing amplitude of the swing rod (42) is at the preset minimum value. At the same time, the first spring (64) and the second spring (69) jointly support the pressure roller (63), so that the inclined surface of the drive wheel (68) and the drive block (67) is in the initial separation state. The second magnetic plate (56) is located in the initial position away from the center of the fixed disk (52). The system enters the standby preparation state. C: The large circular knitting machine starts to run at high speed. The power shaft of the wire feeding roller drives the air supply equipment to rotate synchronously. When the wire feeding rate increases, the air intake of the air supply equipment into the piston cylinder (45) is greater than the exhaust volume of the air outlet pipe (49) under the limitation of the air pressure control valve (410). The pressure inside the piston cylinder (45) increases, pushing the piston rod (46) to the left, which in turn drives the drive sleeve (47) and the internal ball (7) to the left. Since the drive rod (446) continues to move up and down under the drive of the reciprocating drive component (44), the leftward movement of the drive sleeve (47) changes the relative contact position between the roller (8) and the drive rod (446), causing the swing rod (42) to swing back and forth at a larger angle around the rotating seat. The swing amplitude of the adjusting roller (43) increases accordingly, thereby compensating for the yarn tension fluctuation caused by the increase in the wire feeding rate. When the wire feeding rate decreases, the air intake decreases, the piston moves to the right under the action of the pressure difference, and the swing amplitude of the adjusting roller (43) decreases accordingly, realizing reverse compensation. D: The yarn is driven by high-speed friction on the surface of the fixed roller (55). When the yarn tension increases instantaneously, the drag force exerted by the yarn on the fixed roller (55) increases, which overcomes the initial magnetic repulsion between the first magnetic plate (54) and the second magnetic plate (56), forcing the first magnetic plate (54) to move inward along the fixed groove (53). Since the magnetic poles of the first magnetic plate (54) and the second magnetic plate (56) repel each other, the instantaneous tension peak is absorbed. The first magnetic plate (54) corresponding to the six fixed rollers (55) responds independently and makes fine adjustments according to the tension of the yarn segments they contact, so as to achieve distributed adaptive balance of tension and avoid weaving defects caused by uneven local tension. E: When the yarn still has excessive residual tension after being adjusted by the speed dynamic compensation adjustment mechanism (4) and the adaptive magnetic buffer adjustment mechanism (5), the tension will press down on the pressure roller (63). After the pressure roller (63) is subjected to force, it drives the slider (62) to move down along the slide groove (61) through the bearing seat, compressing the first spring (64). The drive wheel (68) on the back of the slider (62) then descends, squeezing the drive block (67) that abuts against its inclined surface, forcing the push plate (66) to move outward along the guide rod (65) towards the fixed box (1). The side moves horizontally, compressing the second spring (69). The outward movement of the push plate (66) pulls the second magnetic plate (56) towards the center of the fixed disk (52) through the fixed shaft (58) and the support rod (57), increasing the magnetic repulsion distance between the second magnetic plate (56) and the first magnetic plate (54), thereby reducing the constraint stiffness on the yarn, automatically releasing excessive tension, and preventing yarn breakage. When the tension returns to normal, the first spring (64) and the second spring (69) reset, and each mechanism returns to its initial position.

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