Overedger thread take-up and thread trapper dynamic adjusting device and overedger

Abstract

The invention discloses an overlock machine thread take-up and thread trapper dynamic adjusting device and an overlock machine, and relates to the technical field of sewing. The technical problems that in the prior art, when thin fabric is sewed by an overlock machine, the fabric wrinkles due to the fact that the tension of machine needles and threads is too large are solved, and meanwhile it is guaranteed that stitches are compact and attractive are solved. The adjusting device comprises a machine shell, a take-up lever, a main shaft and a machine needle thread trapper, the machine needle thread trapper comprises a thread trapper shaft and is provided with a machine needle thread trapper dynamic adjusting mechanism, and the machine needle thread trapper dynamic adjusting mechanism comprises a double-spring structure arranged on the thread trapper shaft in a sleeving mode; the rotating shaft is linked with the main shaft; the eccentric wheel is arranged on the rotating shaft; the sliding rod assembly is connected with the eccentric wheel and the yarn trapper shaft; an external thread adjusting structure is arranged at the front end of the yarn trapper shaft; when the main shaft rotates, the eccentric wheel and the sliding rod assembly enable the pressure of the thread trapper to be increased in the needle stabbing stage and decreased in the needle ascending stage. The adjusting device has the advantages that the thin fabric is effectively prevented from wrinkling during sewing, and meanwhile, the stitch can be kept compact and attractive.

Description

TECHNICAL FIELD

[0001] The present application relates to the sewing technical field, and in particular to a dynamic adjusting device for thread tension and thread clamp of an overlock machine. BACKGROUND

[0002] As a key equipment in the field of garment processing, the thread tension control system of an overlock machine directly affects the sewing quality and fabric adaptability. In the sewing process of thin fabrics (such as silk, chiffon, etc. with a grammage <100 g / m 2 The accurate control of needle thread tension is particularly crucial. The traditional technology realizes stitch formation through the cooperation of a fixed-pressure thread clamp and a thread tensioner with equal curvature, but this static adjusting mode cannot meet the dual requirements of "preventing fabric wrinkling" and "ensuring tight stitches", which has become a technical bottleneck restricting the development of high-end thin fabric sewing processes.

[0003] The overlock machine thread passing structure disclosed in the prior art patent CN113235236B has the following content in independent claim 1: "An overlock machine thread passing structure, comprising a first thread clamp, a second thread clamp, a first thread passing plate, a thread tensioner, a thread passing plate, an upper needle, and a lower needle, the thread tensioner is rotationally connected with the machine body of the overlock machine, the thread passing plate is provided with a first thread passing part and a second thread passing part, a first needle thread sequentially passes through the first thread passing plate, the thread tensioner, the first thread passing part, and the upper needle, and a second needle thread sequentially passes through the first thread passing plate, the thread tensioner, the second thread passing part, and the lower needle."

[0004] This technology controls the thread path of the upper and lower needles by setting double thread passing parts, which improves the stability of the thread storage amount, but the design of keeping the thread clamp pressure constant has the following technical problems when sewing thin fabrics: if the needle thread tension is too large (the thread clamp pressure is too high), the fabric will be excessively stretched and wrinkled, and if the thread clamp pressure is simply reduced to reduce wrinkling, the needle thread tension will be insufficient, resulting in floating threads, loose stitches, and other problems (affecting the appearance). SUMMARY

[0005] The present application provides a dynamic adjusting device for thread tension and thread clamp of an overlock machine, which solves the technical problem of how to prevent fabric wrinkling caused by excessive needle thread tension when sewing thin fabrics with an overlock machine while ensuring tight and beautiful stitches, and achieves the technical effect of effectively preventing thin fabric sewing from wrinkling while maintaining tight and beautiful stitches.

[0006] The present application provides a dynamic adjusting device for thread tension and thread clamp of an overlock machine, which includes a machine housing, a thread tensioner, a main shaft, and a needle thread clamp, the needle thread clamp includes a thread clamp shaft, and is characterized by:

[0007] The machine needle clamp threader dynamic adjustment mechanism comprises:

[0008] a) a double spring structure fitted on the clamp threader shaft;

[0009] b) a rotating shaft linked with the main shaft and an eccentric wheel fitted on the rotating shaft;

[0010] c) a slide bar assembly connecting the eccentric wheel and the clamp threader shaft;

[0011] The front end of the clamp threader shaft is provided with an external thread adjustment structure;

[0012] When the main shaft rotates, the clamp threader pressure is increased in the machine needle downward piercing stage and decreased in the machine needle upward stage through the eccentric wheel and the slide bar assembly.

[0013] As a preferred, the thread lifting lever is provided with a special arc section corresponding to:

[0014] a) left machine needle: main shaft rotation angle 120°-150°;

[0015] b) right machine needle: main shaft rotation angle 115°-145°;

[0016] The definition is that the machine needle highest point corresponds to the main shaft 0°.

[0017] As a preferred, the rotating shaft installation position is adjustable and configured as:

[0018] a) machine needle highest point, the clamp threader shaft is in the leftmost position;

[0019] b) machine needle downward piercing stage (0°-180°) pressure increase to peak;

[0020] c) machine needle upward stage (180°-360°) pressure decrease.

[0021] As a preferred, the machine needle clamp threader further comprises a cover plate fixedly installed on the machine shell, a first clamp thread piece and a second clamp thread piece sleeved on the same side of the cover plate, the second clamp thread piece is fixedly connected with the cover plate, the clamp threader shaft is sleeved on the cover plate and can move left and right relative to the cover plate, both ends of the clamp threader shaft are located on both sides of the cover plate, the rear end of the clamp threader shaft is fixedly installed with a limiting column, the front end of the clamp threader shaft is provided with a pressure regulating stop sleeve and the above-mentioned external thread adjustment structure, the external thread adjustment structure comprises an adjusting nut, the adjusting nut is threadedly connected with the front end of the clamp threader shaft, the pressure regulating stop sleeve can move relative to the clamp threader shaft and is sleeved on the clamp threader shaft, and the pressure regulating stop sleeve is abuttingly connected with the adjusting nut close to the cover plate, the above-mentioned double spring structure comprises an inner layer spring and an outer layer spring, one end of the inner layer spring is connected with the cover plate, and the other end is connected with the limiting column, one end of the outer layer spring is connected with the first clamp thread piece, and the other end is connected with the pressure regulating stop sleeve.

[0022] Preferably, the outer spring has a wire diameter of 0.5-0.8 mm to provide basic pressure; the inner spring has a wire diameter of 0.8-1.2 mm to provide additional pressure when the slide bar is in action; and the difference in free length between the two springs is 3-5 mm.

[0023] Preferably, the slide rod assembly includes a slide rod and a slider that are fixedly connected to each other. The slider has an eccentric shaft hole that matches the eccentric wheel. The eccentric wheel is installed in the eccentric shaft hole. The slide rod is fixedly connected to the limiting post.

[0024] Preferably, the contact surface between the eccentric shaft hole and the eccentric wheel is provided with a self-lubricating coating.

[0025] Preferably, a cylindrical body is also fixedly installed on the cover plate. An installation hole is opened in the cylindrical body, and the aforementioned limiting post and inner spring are located in the installation hole. An elongated guide groove is opened on the side wall of the cylindrical body along the axis of the wire clamp shaft. The elongated guide groove is connected to the aforementioned installation hole and extends to the end face of the cylindrical body away from the cover plate. A threaded hole is opened on the aforementioned limiting post, and a guide post matching the upper and lower groove walls of the aforementioned elongated guide groove is threaded onto the threaded hole. The guide post is located in the elongated guide groove and can move back and forth in the elongated guide groove.

[0026] Preferably, a crank is mounted on the rotating shaft, and the crank is connected to the main shaft via a connecting rod.

[0027] An overlock sewing machine, characterized in that it includes the above-mentioned overlock sewing machine thread take-up and thread clamp dynamic adjustment device.

[0028] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0029] 1. Due to the adoption of a dynamic adjustment mechanism for the needle thread tensioner (including a double spring structure, an eccentric wheel and a slide bar assembly), the technical problem of how to avoid fabric wrinkling caused by excessive needle thread tension when sewing thin fabrics with an overlock sewing machine, while ensuring tight and beautiful stitches, is effectively solved in the existing technology. This achieves the technical effect of effectively preventing wrinkling when sewing thin fabrics while maintaining tight and beautiful stitches.

[0030] 2. Due to the adoption of a special arc section thread take-up lever design (left needle 120°-150°, right needle 115°-145°), the problem of inaccurate thread release when the needle thread loop detaches from the lower looper is effectively solved, thereby achieving the technical effect of reducing the thread release speed by 20%-30% in the key phase interval, and significantly improving the stitch formation quality of thin material sewing.

[0031] 3. The adoption of double-spring differentiation design (0.8-1.2mm inner layer, 0.5-0.8mm outer layer) effectively solves the problem of poor linearity of single-spring pressure adjustment, thereby realizing the technical effect of two-stage pressure precise control.

[0032] 4. The adoption of the precise matching structure of guide groove and guide column effectively solves the problem of pressure fluctuation caused by the shaft deflection of the thread clamp, and realizes the precise and stable action of the thread clamp shaft. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is the structure diagram of the thread tension and thread clamp dynamic adjustment device of the overlock machine.

[0034] Figure 2 is the structure diagram of the needle thread clamp dynamic adjustment mechanism in embodiment one.

[0035] Figure 3 is the partial structure diagram of Figure 2 .

[0036] Figure 4 is the structure diagram of the thread tension lever in embodiment two.

[0037] Figure 5 is the structure diagram of the needle thread clamp dynamic adjustment mechanism in embodiment three.

[0038] Figure 6 is the change diagram of the thread clamp pressure.

[0039] Figure 7 is the structure diagram of the thread tension lever in the prior art.

[0040] In the figure, 1, machine housing; 2, thread tension lever; 3, main shaft; 4, needle thread clamp; 5, thread clamp shaft; 6, rotating shaft; 7, eccentric wheel; 8, cover plate; 9, first thread clamp piece; 10, second thread clamp piece; 11, limiting column; 12, pressure adjustment stop sleeve; 13, adjusting nut; 14, inner layer spring; 15, outer layer spring; 16, sliding rod; 17, sliding block; 18, cylinder; 19, mounting hole; 20, long strip-shaped guide groove; 21, threaded hole; 22, crank; 23, connecting rod. DETAILED DESCRIPTION

[0041] The embodiment of the present application provides an overlock machine thread tension and thread clamp dynamic adjustment device, solves the technical problem of how to avoid fabric wrinkling caused by excessive needle thread tension when sewing thin fabric with an overlock machine in the prior art, and ensures that the stitch is tight and beautiful, and realizes the technical effect of effectively preventing thin fabric from wrinkling while maintaining the tight and beautiful stitch.

[0042] The technical scheme in the embodiment of the present application solves the problem that the fabric wrinkles and the stitch is loose, and the general idea is as follows:

[0043] By adopting the needle threader 4 dynamic adjustment mechanism (including double spring structure, eccentric wheel 7 and slide bar assembly), when the main shaft 3 rotates, the threader pressure is increased in the needle down stage and decreased in the needle up stage through the eccentric wheel 7 and slide bar assembly. Specifically: the needle down stage makes the threader provide gradually increasing pressure, and when the needle reaches the vicinity of the lowest point, the threader pressure reaches the maximum. In this process, because the threader pressure increases, the thread lifting mechanism needs to overcome greater threader friction to pull the thread from the bobbin while retracting the needle thread, which reduces the amount of thread consumed from the bobbin. In addition, because the thread lifting mechanism slows down the amount of thread released during the process of the needle thread loop about to be detached from the lower bent needle to the tightening process, it ensures that the needle thread is tight and beautiful on the fabric. In the needle up stage, the thread lifting mechanism retracts a part of the excess needle thread in advance, and at the same time the threader pressure gradually decreases, so as to ensure that when the lower bent needle hooks the thread, the fabric will not be wrinkled due to the large tension of the face thread. Thus, the problem of "fabric wrinkling" and "loose stitches" is solved.

[0044] Embodiment one

[0045] As shown in Figure 1 and 2 , a dynamic adjustment device for thread lifting and thread clamping of an overlock machine is provided, which comprises a machine housing 1, a thread lifting lever 2, a main shaft 3, and a needle threader 4. The needle threader 4 comprises a threader shaft 5, and the adjustment device is provided with a needle threader 4 dynamic adjustment mechanism, which comprises:

[0046] a) a double spring structure fitted on the threader shaft 5;

[0047] b) a rotating shaft 6 linked with the main shaft 3 and an eccentric wheel 7 provided on the rotating shaft 6;

[0048] c) a slide bar assembly connecting the eccentric wheel 7 and the threader shaft 5;

[0049] The front end of the threader shaft 5 is provided with an external thread adjustment structure;

[0050] When the main shaft 3 rotates, the threader pressure is increased in the needle down stage and decreased in the needle up stage through the eccentric wheel 7 and slide bar assembly. Specifically, the installation position of the rotating shaft 6 is adjustable and is configured as:

[0051] a) when the needle is at the highest point, the threader shaft 5 is at the leftmost position (that is, away from the eccentric shaft end);

[0052] b) the pressure increases to the peak value in the needle down stage (0°-180°);

[0053] c) the pressure decreases in the needle up stage (180°-360°).

[0054] Specifically, as shown in Figure 2 and3 As shown, the needle thread clipper 4 further comprises a cover plate 8 fixedly installed on the casing 1, and a first thread clamping sheet 9 and a second thread clamping sheet 10 sleeved on the same side of the cover plate 8, the second thread clamping sheet 10 being fixedly connected with the cover plate 8, the thread clipper shaft 5 being threaded through the cover plate 8 and capable of moving left and right relative to the cover plate 8, both ends of the thread clipper shaft 5 being located at both sides of the cover plate 8, the rear end of the thread clipper shaft 5 being fixedly installed with a limiting column 11, the front end of the thread clipper shaft 5 being provided with a pressure regulating stop sleeve 12 and an external thread adjusting structure, the external thread adjusting structure comprising an adjusting nut 13, the adjusting nut 13 being threadedly connected with the front end of the thread clipper shaft 5, the adjusting nut 13 being used for manually adjusting the needle thread clipper 4, the pressure regulating stop sleeve 12 being movably sleeved on the thread clipper shaft 5 relative to the thread clipper shaft 5 and being abuttingly connected with the adjusting nut 13 at the end close to the cover plate 8, the double-spring structure comprising an inner spring 14 and an outer spring 15, one end of the inner spring 14 being connected with the cover plate 8 and the other end being connected with the limiting column 11, one end of the outer spring 15 being connected with the first thread clamping sheet 9 and the other end being connected with the pressure regulating stop sleeve 12. The wire diameter of the outer spring 15 of the embodiment is 0.5-0.8 mm, providing a basic pressure; the wire diameter of the inner spring 14 is 0.8-1.2 mm, providing an additional pressure when the slide rod acts; the free length difference of the two springs is 3-5 mm, and a double-spring differential design (0.8-1.2 mm for the inner spring and 0.5-0.8 mm for the outer spring) is adopted, effectively solving the problem of poor linearity of single-spring pressure adjustment, and further realizing the technical effect of two-stage pressure accurate control. Figure 1 As shown, the rotating shaft 6 is installed with a crank 22, the crank 22 being drivingly connected with the main shaft 3 through a connecting rod 23.

[0055] Specifically, as shown, Figure 2 The slide rod assembly comprises a slide rod 16 and a sliding block 17 fixedly connected with each other, the sliding block 17 being provided with an eccentric shaft hole matched with the eccentric wheel 7, the eccentric wheel 7 being installed in the eccentric shaft hole, the slide rod 16 being fixedly connected with the limiting column 11, and the contact surface between the eccentric shaft hole and the eccentric wheel 7 being provided with a self-lubricating coating. Since the slide rod assembly adopts the self-lubricating coating, the problem of wear caused by high-frequency reciprocating motion is effectively solved, and the service life of the key moving parts is further improved to more than 500,000 times, and the maintenance period is extended to 3 times of that of the traditional structure.

[0056] The specific working principle is as follows:

[0057] The main shaft 3 rotates, driving the rotating shaft 6 to rotate via the connecting rod 23 and crank 22. The rotation of the rotating shaft 6 drives the eccentric wheel 7 on it to rotate, thereby driving the slider 17 and slider 16 on the sliding rod assembly to reciprocate. The reciprocating motion of the slider 16 drives the limiting post 11 and the thread clamp shaft 5 to reciprocate, thus dynamically changing the pressure of the inner spring 14 and outer spring 15 on the first thread clamping piece 9, achieving dynamic adjustment of the pressure between the first thread clamping piece 9 and the second thread clamping piece 10. Specifically, in this embodiment, keeping the main shaft 3 rotation angle at 0 degrees, when the rotating shaft 6 is adjusted to the highest point of the needle, the thread clamp shaft 5 is at its leftmost position. This means that the clamping pressure of the first thread clamping piece 9 and the second thread clamping piece 10 on the needle thread is at its minimum, and the thread clamp pressure is at its minimum. This position of the rotating shaft 6 is used as the installation standard. Through the structural design of the eccentric wheel 7, the change in the thread clamp pressure during one revolution of the main shaft 3 is as follows: Figure 6 As shown, the pressure increases to its peak during the needle insertion phase (0°-180° rotation of the main shaft 3) and decreases during the needle rise phase (180°-360° rotation of the main shaft 3). The needle insertion phase gradually increases the pressure provided by the thread tensioner, reaching its maximum pressure near the lowest point of the needle. During this process, due to the increased tensioner pressure, the take-up mechanism needs to overcome greater tensioner friction to pull the thread from the spool while retracting the needle thread, reducing the amount of thread consumed from the spool. Furthermore, the take-up mechanism slows down the thread release as the needle loop is about to detach from the lower looper and tighten, ensuring a tight and aesthetically pleasing thread on the fabric. During the needle rise phase, the take-up mechanism retracts some excess needle thread in advance, while the tensioner pressure gradually decreases to prevent wrinkling of the fabric due to excessive tension when the lower looper hooks the thread. It effectively solves the technical problem of how to avoid wrinkling of thin fabrics due to excessive needle and thread tension when sewing with an overlock sewing machine, while ensuring tight and beautiful stitches. It achieves the technical effect of effectively preventing wrinkling of thin fabrics while maintaining tight and beautiful stitches.

[0058] Further elaborated as follows, when the needle penetrates the fabric, the loop between the lower needle and the needle will gradually decrease, at which time the excess needle thread will be released. A portion of the needle thread is collected by the thread tensioner, and a portion will be consumed by the needle penetration. As the needle penetrates, the thread tensioner will gradually release the collected thread, and the amount of thread required by the needle penetration and the amount of needle thread consumed on the fabric will be greater than the sum of the thread released by the decrease of the loop between the lower needle and the needle and the thread released by the thread tensioner, at which time the resistance of the thread clamp needs to be overcome to pull the thread from the spool to meet the sewing requirements. When sewing thin fabric, the amount of needle thread consumed on the fabric is relatively small due to the thinness of the fabric, and both the fabric and the thread have a certain elasticity. In order to make the stitches tight and beautiful, the fabric needs to be tightened after the needle thread is collected, and then the thread needs to be pulled from the spool when needed, so the thread pulled from the spool is relatively small. If the pressure of the needle thread clamp 4 is small, the frictional resistance that the pulled thread needs to overcome is small, and it will be easier to pull the thread from the spool. In addition, due to the small pressure of the thread clamp, the tension of the needle thread is not enough, i.e., the tension is small, so it is difficult to tighten the needle thread, and thus the problem of thread floating is prone to occur. The structure of the present embodiment gradually increases the pressure of the thread clamp during the needle penetration stage, so it is not so easy to pull the thread from the spool, thereby relatively less thread is pulled from the spool, and the problem of thread floating is solved.

[0059] When the needle rises, the lower needle will hook the needle thread to form a loop. When the lower needle moves, the loop will gradually increase, requiring more needle thread. At this time, the needle rising will release a portion of the needle thread, and the movement of the thread tensioner will collect a portion of the thread. If the tension of the needle thread is too large, i.e., the tension of the needle thread is too large, the lower needle will easily pull and stretch the fabric along with the needle thread as the lower needle and the thread tensioner 2 move, thereby increasing the degree of fabric wrinkling. The structure of the present embodiment reduces the pressure of the thread clamp during the needle rising stage, thereby solving the problem of pulling and stretching the fabric and thus increasing the degree of fabric wrinkling.

[0060] Embodiment Two

[0061] The present embodiment is based on Embodiment One and has a special arc surface section on the thread tensioner 2, as shown in Figure 4 , which corresponds to:

[0062] a) Left needle: main shaft 3 rotation angle 120° to 150° interval;

[0063] b) Right needle: main shaft 3 rotation angle 115° to 145° interval;

[0064] The definition is that the highest point of the needle corresponds to 0 degrees of the main shaft.

[0065] The structure of the thread tensioner 2 in the prior art is shown in Figure 7 , the arc surface where the left and right needle threads slide is usually a circular arc tangent to two straight lines, and the needle thread slides back and forth on the circular surface of the thread tensioner 2 during the sewing process; the present embodiment is a modification of the above structure, as shown in Figure 4As shown, when the needle thread slides to the surface shown at A in Figure 4 corresponds to the main shaft 3 rotation angle 120°-150°, and the right needle A surface corresponds to the main shaft 3 rotation angle 115°-145°. In this embodiment, other conditions being unchanged, the surface of the thread tensioning rod 2 in the prior art is changed from a straight line to an arc surface, and the height is appropriately increased. This design can slow down the thread releasing rate of the thread tensioning rod 2 when the needle thread ring is separated from the lower needle to the needle thread tightening process, and also reduces the thread releasing amount of the thread tensioning rod 2, so that it is easier to tighten the needle thread when sewing thin materials.

[0066] Due to the special arc surface section of the thread tensioning rod 2 design (left needle 120°-150°, right needle 115°-145°), the problem of inaccurate thread releasing when the needle thread ring is separated from the lower needle is effectively solved, thereby achieving the technical effect of slowing down the thread releasing speed by 20%-30% in the key phase interval, and significantly improving the stitch forming quality of thin material sewing.

[0067] Embodiment Three

[0068] The difference between this embodiment and embodiment one is that, as shown in Figure 5 The cover plate 8 is also fixedly installed with a cylinder 18, the cylinder 18 is provided with an installation hole 19, the limiting column 11 and the inner layer spring 14 are located in the installation hole 19, a long strip-shaped guide groove 20 is formed on the side wall of the cylinder 18 along the axis center line direction of the thread clamp shaft 5, the long strip-shaped guide groove 20 penetrates through the installation hole 19 and penetrates to the end face of the cylinder 18 away from the cover plate 8, a threaded hole 21 is formed on the limiting column 11, a guide column (not shown in the figure) matched with the upper and lower groove walls of the long strip-shaped guide groove 20 is threadedly connected on the threaded hole 21, and the guide column is located in the long strip-shaped guide groove 20 and can move back and forth in the long strip-shaped guide groove 20. The other structures and working principles are the same as those of embodiment one, and will not be described here.

[0069] Due to the precise matching structure of the guide groove and the guide column, the problem of pressure fluctuation caused by the deflection of the thread clamp shaft 5 is effectively solved, and the precise and stable action of the thread clamp shaft 5 is realized.

[0070] Embodiment Four

[0071] This embodiment provides an overlock machine, which comprises the overlock machine thread tensioning and thread clamp device in embodiment one.

[0072] While the preferred embodiments of the application have been described, additional variations and modifications can be made to these embodiments by those skilled in the art once they have the benefit of the present disclosure without departing from the spirit and scope of the application. Accordingly, it is intended that the appended claims include all such modifications and variations as fall within the scope of the present application.

[0073] It is apparent that those skilled in the art can make various changes and modifications to the application without departing from the spirit and scope of the application. It is therefore intended that the present application cover all such changes and modifications that are within its scope.

Claims

1. A dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine, comprising a machine housing (1), a thread take-up lever (2), a main shaft (3), and a needle thread clamp (4), wherein the needle thread clamp (4) includes a thread clamp shaft (5), characterized in that: The machine needle thread clamp (4) is provided with a dynamic adjustment mechanism, which includes: a) A double-spring structure fitted onto the wire clamp shaft (5); b) A rotating shaft (6) that is linked to the main shaft (3) and an eccentric wheel (7) mounted on the rotating shaft (6); c) A slide rod assembly connecting the eccentric wheel (7) and the wire clamp shaft (5); The front end of the wire clamp shaft (5) is provided with an external thread adjustment structure; When the spindle (3) rotates, the pressure of the wire clamp increases during the needle insertion stage and decreases during the needle rise stage through the eccentric wheel (7) and the slide rod assembly.

2. The dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 1, characterized in that, The line-lifting rod (2) has a special arc section, which corresponds to: a) Left needle: Main spindle (3) rotation angle 120° to 150°; b) Right needle: Main spindle (3) rotation angle 115° to 145°; The highest point of the needle corresponds to 0 degrees on the spindle.

3. The dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 2, characterized in that, The mounting position of the rotating shaft (6) is adjustable, and it is configured as follows: a) When the needle is at its highest point, the wire clamp shaft (5) is at its leftmost position; b) During the needle insertion phase (0°-180°), the pressure increases to its peak value; c) Pressure decreases during the needle rising phase (180°-360°).

4. The dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 3, characterized in that, The needle clamp (4) further includes a cover plate (8) fixedly installed on the housing (1) and a first clamping piece (9) and a second clamping piece (10) sleeved on the same side of the cover plate (8). The second clamping piece (10) is fixedly connected to the cover plate (8). The clamp shaft (5) passes through the cover plate (8) and can move left and right relative to the cover plate (8). The two ends of the clamp shaft (5) are located on both sides of the cover plate (8). A limit post (11) is fixedly installed at the rear end of the clamp shaft (5). The front end of the clamp shaft (5) is provided with a pressure adjusting stop sleeve (12) and the aforementioned external thread adjustment structure. The section structure includes an adjusting nut (13), which is threadedly connected to the front end of the wire clamp shaft (5). The pressure regulating stop sleeve (12) is movable relative to the wire clamp shaft (5) and is sleeved on the wire clamp shaft (5) and abuts against the end of the adjusting nut (13) near the cover plate (8). The double spring structure includes an inner spring (14) and an outer spring (15). One end of the inner spring (14) is connected to the cover plate (8) and the other end is connected to the limiting post (11). One end of the outer spring (15) is connected to the first wire clamping piece (9) and the other end is connected to the pressure regulating stop sleeve (12).

5. The dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 4, characterized in that, The outer spring (15) has a wire diameter of 0.5-0.8 mm and provides basic pressure; the inner spring (14) has a wire diameter of 0.8-1.2 mm and provides additional pressure when the slide bar is in action; the difference in free length between the two springs is 3-5 mm.

6. A dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 1, 2, 3, 4, or 5, characterized in that, The slide rod assembly includes a slide rod (16) and a slider (17) fixedly connected to each other. The slider (17) has an eccentric shaft hole that matches the eccentric wheel (7). The eccentric wheel (7) is installed in the eccentric shaft hole. The slide rod (16) is fixedly connected to the limiting post (11).

7. The dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 6, characterized in that, The contact surface between the eccentric shaft hole and the eccentric wheel (7) is provided with a self-lubricating coating.

8. The dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 6, characterized in that, A cylindrical body (18) is also fixedly installed on the cover plate (8). An installation hole (19) is opened in the cylindrical body (18). The aforementioned limiting post (11) and inner spring (14) are located in the installation hole (19). A long strip guide groove (20) is opened on the side wall of the cylindrical body (18) along the axis of the clamp shaft (5). The long strip guide groove (20) is connected to the aforementioned installation hole (19) and extends to the end face of the cylindrical body (18) away from the cover plate (8). A threaded hole (21) is opened on the aforementioned limiting post (11). A guide post that matches the upper and lower groove walls of the long strip guide groove (20) is threaded onto the threaded hole (21). The guide post is located in the long strip guide groove (20) and can move back and forth in the long strip guide groove (20).

9. The dynamic adjustment device for thread take-up and thread clamp of an overlock sewing machine as described in claim 1, characterized in that, A crank (22) is mounted on the rotating shaft (6), and the crank (22) is connected to the main shaft (3) via a connecting rod (23).

10. An overlock sewing machine, characterized in that, The device includes the thread take-up and thread clamp dynamic adjustment device for overlock sewing machines as described in any one of claims 1-9.

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