Adjustment Device and Adjustment Method for a Sewing Machine

Abstract

The present invention discloses an adjusting device and an adjusting method for a sewing machine, specifically relating to the technical field of sewing machines. The sewing machine includes a frame, and a presser mechanism, a needle feeding mechanism, and a thread hooking mechanism are arranged inside the frame. The presser mechanism includes a presser bar that vertically penetrates the front end of the frame and slides inside the frame. The presser mechanism further includes a pressure adjusting mechanism and a cloth feeding mechanism. The pressure adjusting mechanism includes an air cylinder fixedly connected to the frame. An adjusting ring is arranged inside the air cylinder cavity. The adjusting ring can slide synchronously with the presser bar and squeeze the gas inside the air cylinder. A second elastic member is arranged inside the air cylinder, and two ends of the second elastic member are respectively fixedly connected to the top end of the adjusting ring and the inner top of the air cylinder. The outer wall of the air cylinder is provided with a first exhaust hole and a second exhaust hole. When the thickness of the cloth changes, the present invention can automatically adjust the pressure of the presser foot on the cloth and the cloth feeding depth of the feed dog according to the cloth thickness, so as to ensure the smoothness of sewing and the uniformity of stitch pitch.

Description

Technical Field

[0001] The present invention relates to the technical field of sewing machines. More specifically, the present invention relates to an adjusting device and an adjusting method for a sewing machine. Background Art

[0002] A sewing machine is a machine that uses one or more sewing threads to form one or more stitches on a fabric, so as to interweave or sew together one or more layers of sewing materials. A sewing machine usually consists of a feeding device, a base, a transmission, and accessories. Through the reasonable cooperation of the movements of each mechanism, it works cyclically to sew the sewing materials together. When sewing fabrics of different thicknesses, it is necessary to adjust the presser foot pressure to ensure the smoothness of feeding and the uniformity of stitch density.

[0003] However, existing sewing machines usually need to stop the machine and then adjust the height and pressure of the presser foot according to the fabric thickness, and cannot automatically adjust the pressure according to the fabric thickness during use. Moreover, when sewing fabrics with a relatively large thickness, only adjusting the presser foot pressure will result in insufficient pressure, and the smoothness of sewing and the uniformity of stitch density cannot be guaranteed. Summary of the Invention

[0004] In order to overcome the above-mentioned defects of the prior art, embodiments of the present invention provide an adjusting device and an adjusting method for a sewing machine, and adjust the feeding pressure by setting a pressure adjusting mechanism and an adjusting box, so as to solve the problems raised in the above-mentioned background art.

[0005] To achieve the above object, the present invention provides the following technical solution: An adjusting device for a sewing machine, comprising: a frame, a material pressing mechanism, a material piercing mechanism, and a thread hooking mechanism are arranged inside the frame. The material pressing mechanism includes a presser bar vertically penetrating the front end of the frame and sliding inside the frame, and further includes a pressure adjusting mechanism and a feeding mechanism;

[0006] The pressure adjusting mechanism includes an air cylinder fixedly connected to the frame. An adjusting ring is arranged inside the air cylinder cavity. The adjusting ring can slide synchronously with the presser bar and squeeze the gas inside the air cylinder. A second elastic member is arranged inside the air cylinder. Two ends of the second elastic member are respectively fixedly connected to the top end of the adjusting ring and the inner top of the air cylinder. The outer wall of the air cylinder is provided with a first exhaust hole and a second exhaust hole;

[0007] The feeding mechanism includes an adjusting box. Two air storage boxes are arranged inside the adjusting box. A pressing block that moves according to the air pressure inside the air storage box is arranged inside each air storage box. One end of each pressing block is rotatably connected to a support plate. The other ends of the two support plates away from the pressing blocks are commonly connected to a top block. The two support plates are respectively rotatably connected to the adjusting box. Each air storage box is provided with an air inlet hole.

[0008] Preferably, a tooth rest is fixedly connected to the side wall of the adjustment box. A limiting groove is formed in one side of the adjustment box away from the tooth rest. A support column is fixedly connected to the inner bottom of the adjustment box. A fixing member is slidably connected to the outer wall of the support column. The front end of the fixing member passes through the limiting groove and is fixedly connected to a feed dog. The bottom of the fixing member contacts the top block.

[0009] Preferably, a threaded sleeve is sleeved on the outer wall of the pressure bar. A first pressure ring is threadedly connected to the outer wall of the threaded sleeve. A guiding groove is formed inside the first pressure ring. A second pressure ring capable of clamping the pressure bar is arranged on the outer wall of the pressure bar. A first elastic member is sleeved on the outer wall of the threaded sleeve. Two ends of the first elastic member are respectively fixedly connected to the bottom end of the first pressure ring and the top end of the second pressure ring. A second motor is fixedly connected to the upper end of the machine frame. The output end of the second motor is fixedly connected to a driving wheel. The driving wheel meshes with a driven wheel. One end of the driven wheel is fixedly connected to the threaded sleeve. One end of the pressure bar is fixedly connected to a presser foot holder. The bottom end of the presser foot holder is rotatably connected to a presser foot.

[0010] Preferably, the material piercing mechanism includes a needle bar vertically penetrating the front end of the machine frame and sliding inside the machine frame. A fixing ring is fixedly connected to the outer wall of the needle bar. A top rod is fixedly connected to the side wall of the fixing ring. A first connecting rod is rotatably connected to the side wall of the fixing ring through a shaft.

[0011] Preferably, a guiding groove is arranged inside the machine frame. A switch is arranged on the top side wall of the guiding groove. A slider is slidably connected to the inner wall of the guiding groove. A spring is arranged inside the guiding groove cavity. Two ends of the spring are respectively fixedly connected to the bottom surface of the slider and the inner bottom surface of the guiding groove.

[0012] Preferably, an upper shaft is arranged inside the machine frame cavity. A first motor is fixedly connected to the rear end of the machine frame. The output end of the first motor is fixedly connected to the upper shaft. One end of the upper shaft away from the first motor is eccentrically rotatably connected to the first connecting rod.

[0013] Preferably, a tooth lifting shaft is arranged at the bottom of the machine frame. One end of the tooth lifting shaft is slidably connected to a lower shaft crank. One end of the tooth lifting shaft away from the lower shaft crank is slidably connected to the tooth rest. One end of the lower shaft crank is rotatably connected to a tooth lifting connecting rod. One end of the tooth lifting connecting rod away from the lower shaft crank is rotatably connected to the upper shaft.

[0014] Preferably, a feed shaft is arranged inside the bottom of the machine frame. One end of the feed shaft is rotatably connected to one end of the tooth rest away from the tooth lifting shaft. One end of the feed shaft away from the tooth rest is rotatably connected to a feed connecting rod. The feed connecting rod is slidably connected to the upper shaft.

[0015] Preferably, the thread hooking mechanism includes a lower shaft. A bobbin case support is provided at one end of the lower shaft close to the needle bar support. The bobbin case support is fixedly connected to the machine frame. A bobbin case is embedded in the bobbin case support. The other end of the lower shaft away from the bobbin case support is slidably connected to a lower shaft crank. A bobbin is rotatably connected inside the bobbin case.

[0016] An adjustment method for a sewing machine adjustment device includes the following steps:

[0017] S1. Place the fabric to be sewn above the feed dog of the sewing machine.

[0018] S2. Start the second motor to adjust the initial pressure.

[0019] S3. Start the first motor to sew.

[0020] S4. When the fabric changes from thin to thick, the presser foot rotates, the presser bar slides upward, and the second elastic member and the first elastic member are compressed, increasing the pressure.

[0021] S5. When the fabric is thick, the rising of the presser bar increases the pressure, causing the feed dog to rise to increase the pressure and the depth of fabric feeding.

[0022] S6. When the resistance on the feed dog is too large due to excessive pressure on the fabric and the feed dog cannot feed the fabric, the slider touches the switch, the second motor rotates in the reverse direction, and the first pressure ring rises, reducing the pressure.

[0023] The technical effects and advantages of the present invention:

[0024] 1. In the present invention, the second motor drives the rotation of the threaded sleeve, causing the first pressure ring to descend or rise as the threaded sleeve rotates. The movement of the first pressure ring changes the force on the second pressure ring, enabling the adjustment of the initial pressure for fabrics of different materials at the same height.

[0025] 2. In the present invention, through the pressure adjustment mechanism, during the working process, the sewing machine automatically increases the pressure of the presser foot on the fabric by changing the height of the presser bar according to the change in the fabric thickness through the presser foot, preventing the problem of stopping the machine to adjust the pressure due to the increase in fabric thickness.

[0026] 3. When sewing thick fabrics in the present invention, while increasing the pressure on the fabric by raising the height of the presser bar, the height of the feed dog is raised by the top plate to increase the depth of fabric feeding to ensure the smoothness of fabric feeding.

[0027] 4. When the resistance on the feed dog is too large due to excessive pressure on the fabric and the feed dog cannot feed the fabric in the present invention, the slider touches the switch, the second motor rotates in the reverse direction, and the first pressure ring rises, reducing the pressure, preventing the problems of the feed dog being unable to feed the fabric or even tearing the fabric and damaging the machine due to excessive pressure on the fabric. Description of the Drawings

[0028] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0029] Figure 2 This is a bottom view of the overall structure of the present invention.

[0030] Figure 3 This is a cross-sectional view of the material pressing mechanism and the material piercing mechanism of the present invention.

[0031] Figure 4 This is a schematic diagram of the structure of the material pressing mechanism of the present invention.

[0032] Figure 5 This is a cross-sectional view of the material pressing mechanism of the present invention.

[0033] Figure 6 This is a schematic diagram of the partial structure of the present invention.

[0034] Figure 7 This is a schematic diagram of the structure of the cloth feeding mechanism of the present invention.

[0035] Figure 8 This is a schematic diagram of a partial structure of the cloth feeding mechanism of the present invention.

[0036] Figure 9 This is a cross-sectional view of the cloth feeding mechanism of the present invention.

[0037] Figure 10 of the present invention Figure 9 is an enlarged view of the structure of part A.

[0038] Figure 11 This is an exploded view of the partial structure of the present invention.

[0039] Figure 12 This is a cross-sectional view of the overall structure of the present invention.

[0040] The reference numerals are: 1, frame; 11, guide groove; 12, slider; 13, upper shaft; 14, first motor; 15, lifting tooth shaft; 151, lifting tooth connecting rod; 16, lower shaft crank; 17, feeding shaft; 171, feeding connecting rod; 2, presser mechanism; 21, presser bar; 22, threaded sleeve; 23, first pressure ring; 24, second pressure ring; 25, first elastic member; 26, second motor; 27, driving wheel; 28, driven wheel; 29, presser foot holder; 291, presser foot; 3, pressure adjusting mechanism; 31, air cylinder; 32, adjusting ring; 33, second elastic member; 34, first exhaust hole; 35, second exhaust hole; 4, feeding mechanism; 41, tooth holder; 42, adjusting box; 421, limiting groove; 43, support column; 44, air storage tank; 441, pressing block; 442, support plate; 443, top block; 45, fixing member; 46, feeding tooth; 5, stabbing mechanism; 51, needle bar; 52, fixing ring; 521, ejector rod; 53, first connecting rod; 6, thread hooking mechanism; 61, lower shaft; 62, bobbin case support; 621, bobbin case; 622, bobbin core. Detailed implementation manners

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] Embodiment 1

[0043] In the actual production process, it is found that sewing machines usually need to stop to adjust the height and pressure of the presser foot according to the thickness of the fabric, and cannot automatically adjust the pressure according to the thickness of the fabric during use. To solve the above problems, this embodiment is specifically invented.

[0044] Please refer to Figure 1 and Figure 2 As shown, an adjustment device for a sewing machine according to an embodiment of the present invention includes a frame 1. A presser mechanism 2, a stabbing mechanism 5, and a thread hooking mechanism 6 are arranged inside the frame 1. Combining Figure 3 As shown, the presser mechanism 2 includes a presser bar 21 that vertically penetrates the front end of the frame 1 and slides inside the frame 1.

[0045] Please refer to Figure 3 and Figure 4 As shown, the pressure adjusting mechanism 3 includes an air cylinder 31 fixedly connected to the frame 1. An adjusting ring 32 is arranged inside the air cylinder 31. The inner wall of the adjusting ring 32 is fixedly connected to the inner wall of the presser bar 21. The adjusting ring 32 can slide synchronously with the presser bar 21 and squeeze the gas inside the air cylinder 31; Combining Figure 5As shown, a second elastic member 33 is provided inside the air cylinder 31. The two ends of the second elastic member 33 are respectively fixedly connected to the top end of the adjusting ring 32 and the inner top of the air cylinder 31. The second elastic member 33 is a spring.

[0046] Please refer to Figure 5 As shown, a threaded sleeve 22 is sleeved on the outer wall of the pressure lever 21. A first pressure ring 23 is threadedly connected to the outer wall of the threaded sleeve 22. A guiding groove is provided inside the first pressure ring 23. A second pressure ring 24 is sleeved on the outer wall of the pressure lever 21. A threaded hole is provided on the outer wall of the second pressure ring 24. A locking screw is threadedly connected inside the threaded hole to clamp the pressure lever 21 by the second pressure ring 24. A first elastic member 25 is sleeved on the outer wall of the threaded sleeve 22. The two ends of the first elastic member 25 are respectively fixedly connected to the bottom end of the first pressure ring 23 and the top end of the second pressure ring 24; Combining Figure 3 As shown, a second motor 26 is fixedly connected to the upper end of the frame 1. The output end of the second motor 26 is fixedly connected to a driving wheel 27. The driving wheel 27 meshes with a driven wheel 28. The driven wheel 28 is fixedly connected to one end of the threaded sleeve 22. One end of the pressure lever 21 is fixedly connected to a presser foot holder 29. A presser foot 291 is rotatably connected to the bottom end of the presser foot holder 29. A guiding rod is provided on the frame 1 and is matched with the guiding groove of the first pressure ring 23. The first elastic member 25 is a spring.

[0047] Please refer to Figure 6 As shown, the material piercing mechanism 5 includes a needle bar 51 vertically penetrating the front end of the frame 1 and sliding inside the frame 1. A fixing ring 52 is fixedly connected to the outer wall of the needle bar 51. A first connecting rod 53 is rotatably connected to the rear end of the fixing ring 52.

[0048] Please refer to Figure 6 and Figure 12 As shown, a top shaft 13 is rotatably connected to the inner cavity of the frame 1. A first motor 14 is fixedly connected to the rear end of the frame 1. The output end of the first motor 14 is fixedly connected to the top shaft 13. One end of the top shaft 13 away from the first motor 14 is rotatably connected to the first connecting rod 53.

[0049] Please refer to Figure 7 As shown, the cloth feeding mechanism 4 includes an adjusting box 42. A tooth holder 41 is fixedly connected to the side wall of the adjusting box 42. A limiting groove 421 is provided on one side of the adjusting box 42 away from the tooth holder 41. A support column 43 is fixedly connected to the inner bottom of the adjusting box 42. A fixing member 45 is slidably connected to the outer wall of the support column 43. The front end of the fixing member 45 penetrates through the limiting groove 421 and is fixedly connected to a feed dog 46. The bottom of the fixing member 45 is in contact with the top block 443.

[0050] Please refer to Figure 2 and Figure 11 As shown, a lifting tooth shaft 15 is rotatably connected to the bottom of the frame 1. One end of the lifting tooth shaft 15 is slidably connected to a lower shaft crank 16; Combining Figure 6As shown, one end of the lifting tooth shaft 15 away from the lower shaft crank 16 is slidably connected to the tooth carrier 41. One end of the lower shaft crank 16 is rotatably connected to a lifting tooth connecting rod 151. One end of the lifting tooth connecting rod 151 away from the lower shaft crank 16 is rotatably connected to the upper shaft 13.

[0051] Please refer to Figure 2 and Figure 11 As shown, a feed shaft 17 is rotatably connected to the bottom of the frame 1; in combination with Figure 6 and Figure 12 As shown, one end of the feed shaft 17 is rotatably connected to one end of the tooth carrier 41 away from the lifting tooth shaft 15. One end of the feed shaft 17 away from the tooth carrier 41 is rotatably connected to a feed connecting rod 171. The feed connecting rod 171 is slidably connected to the upper shaft 13.

[0052] Please refer to Figure 3 and Figure 11 As shown, the thread hooking mechanism 6 includes a lower shaft 61. One end of the lower shaft 61 close to the tooth carrier 41 is provided with a bobbin case support 62. The bobbin case support 62 is fixedly connected to the frame 1. A bobbin case 621 is embedded in the bobbin case support 62. One end of the lower shaft 61 away from the bobbin case support 62 is slidably connected to the lower shaft crank 16. A bobbin 622 is rotatably connected inside the bobbin case 621.

[0053] During use, place the fabric to be sewn under the presser foot 291. Lock the presser bar 21 through the second pressure ring 24. When the second motor 26 is started, the threaded sleeve 22 rotates, thereby driving the first pressure ring 23 to move on the threaded sleeve. By the movement of the first pressure ring 23, the compression amount of the first elastic member 25 is changed, thereby changing the pressure received by the second pressure ring 24, so that the pressure received by the presser bar 21 is changed. Apply pressure to the fabric through the presser foot 291 below the presser bar 21. Adjust the initial pressure according to the material and thickness of the fabric to increase applicability and improve work efficiency.

[0054] During the working process, turn on the first motor 14 to drive the upper shaft 13 to rotate, so that the upper shaft 13 drives the first connecting rod 53 to rotate. Drive the needle bar 51 to reciprocate up and down through the first connecting rod 53. While the upper shaft 13 rotates, the lifting tooth connecting rod 151 drives the lower shaft crank 16 to reciprocate, so that the lower shaft 61 drives the bobbin case 621 to rotate inside the bobbin case support 62. While the upper shaft 13 rotates, it drives the feed connecting rod 171 to reciprocate around the upper shaft 13. Drive the feed shaft 17 to rotate through the movement of the feed connecting rod 171. Drive the tooth carrier 41 to reciprocate through the rotation of the feed shaft 17. The reciprocating rotation of the lower shaft crank 16 causes the lifting tooth shaft 15 to reciprocate while following the reciprocating sliding of the lower shaft crank 16, and drive the tooth carrier 41 to reciprocate on the lifting tooth shaft 15 through the reciprocating movement of the lifting tooth shaft 15. Through the cooperation between the lifting tooth shaft 15 and the feed shaft 17, the feed dog 46 moves in a cycle.

[0055] When the sewing fabric becomes thicker, the presser foot 291 drives the presser bar 21 to lift upward according to the fabric thickness. As the presser bar 21 moves upward, the second pressing ring 24 and the adjusting ring 32 move along with the presser bar 21, compressing the first elastic member 25 and the second elastic member 33, increasing the pressure on the presser foot 291 and simultaneously increasing the pressure on the fabric. When the fabric thickness changes from thick to thin, the presser foot 291 drives the presser bar 21 to move downward, causing the first elastic member 25 and the second elastic member 33 to expand, reducing the pressure on the fabric. By lifting and lowering the presser foot 291 according to the fabric thickness while changing the pressure on the fabric, the sewing machine automatically adjusts the pressure according to the fabric thickness during operation, eliminating the need to stop the machine to adjust the pressure, improving work efficiency and sewing smoothness, and ensuring sewing quality.

[0056] Embodiment 2

[0057] In actual use, it is found that when sewing relatively thick fabrics, only adjusting the pressure of the presser foot will result in insufficient pressure, causing uneven feeding and affecting the uniformity of stitch density. Based on the above embodiment, further improvements are made.

[0058] Please refer to Figure 9 and Figure 10 As shown, two air storage tanks 44 are provided inside the adjustment box 42. Inside each air storage tank 44, a pressure block 441 that moves according to the air pressure inside the air storage tank 44 is provided. One end of each pressure block 441 is rotatably connected to a support plate 442. The two support plates 442 are commonly connected to a top block 443 at the ends away from the pressure block 441. The two support plates 442 are respectively rotatably connected to the adjustment box 42. Combining Figure 8 and Figure 7 As shown, each air storage tank 44 is provided with an air inlet hole. Combining Figure 5 As shown, the outer wall of the air cylinder 31 is provided with a first exhaust hole 34 and a second exhaust hole 35. The two air inlet holes are connected to the second exhaust hole 35 through a three-way hose.

[0059] Based on the above embodiments, during use, when the thickness of the fabric increases slightly, the pressure rod 21 moves upward to drive the adjusting ring 32 to rise, causing the gas inside the air cylinder 31 to be squeezed and discharged through the first exhaust hole 34. At the same time, the second elastic member 33 is compressed and the pressure on the fabric increases. When the thickness of the fabric increases significantly, the presser foot 291 drives the pressure rod 21 to rise. By the upward movement of the pressure rod 21, the adjusting ring 32 is driven to rise. When the adjusting ring 32, at the same time, the gas inside the air cylinder 31 is squeezed. When the height of the adjusting ring 32 rises above the first exhaust hole 34, the squeezed gas enters the inside of the air storage tank 44 through the second exhaust hole 35 and the three-way hose. By increasing the air pressure inside the air storage tank 44, the pressing block 441 slides downward inside the air storage tank 44, and at the same time drives the support plate 442 to rotate on the side wall of the adjusting box 42, causing the top block 443 to rise. By the upward movement of the top block 443, the fixing member 45 and the feed dog 46 are driven to slide upward inside the limit groove 421, thereby raising the feed dog 46 to increase the fabric feeding depth. By adjusting the pressure of the presser foot 291 and the fabric feeding depth of the feed dog 46 simultaneously, the smoothness of fabric feeding and the uniformity of sewing stitch pitch are ensured.

[0060] Embodiment 3

[0061] It is found during actual use that when the pressure on the fabric is too large, it will cause the feed dog 46 to be unable to feed the fabric or even tear the fabric. Further improvements are made based on the above embodiments.

[0062] Please refer to Figure 3 As shown, a guide groove 11 is fixedly connected to the frame 1. A switch is provided on the top side wall of the guide groove 11. A slider 12 is slidably connected to the inner wall of the guide groove 11. A spring is provided in the inner cavity of the guide groove 11. The two ends of the spring are respectively fixedly connected to the bottom surface of the slider 12 and the inner bottom surface of the guide groove 11. Combining Figure 6 As shown, a top rod 521 is fixedly connected to the side wall of the fixed ring 52. The top rod 521 corresponds to the guide groove 11. The switch is a prior art and will not be elaborated here.

[0063] When the sewing machine is working normally, the upper shaft 13 is driven to rotate by the first motor 14, so that the first connecting rod 53 drives the fixed ring 52 and its ejector rod 521 to move up and down reciprocally. When the ejector rod 521 moves downward, the ejector rod 521 inserts into the inside of the guide groove 11 to press down the slider 12. At this time, the spring is compressed. When the ejector rod 521 moves upward, the slider 12 gradually rises as the spring expands. Before the slider 12 touches the switch, the ejector rod 521 moves downward again to press the slider 12. When the pressure on the fabric is too large, at this time, the frictional force on the feed dog 46 is relatively large, resulting in the slow reciprocating movement of the feed dog 46 or even the inability of the feed dog 46 to move due to excessive frictional force. At this time, the downward movement of the ejector rod 521 is delayed or even stagnant. At this time, the slider 12 slides inside the guide groove 11 through the expansion of the spring. When the slider 12 slides to the height of the switch and touches the switch, the second motor 26 is started. The second motor 26 rotates in reverse to drive the threaded sleeve 22 to rotate, so that the first pressing ring 23 rises. As the first pressing ring 23 rises, the first elastic member 25 gradually expands, and the pressure on the pressure rod 21 decreases, so that the pressure on the fabric decreases. When the fabric can pass through smoothly, the ejector rod 521 presses the slider 12 again, and the slider 12 no longer contacts the switch, and the second motor 26 is turned off to prevent the problem that the feed dog 46 cannot feed the fabric or even tear the fabric and damage the machine when the pressure on the fabric is too large.

[0064] Embodiment 4

[0065] On the basis of the above embodiments, this embodiment also provides an adjustment method for an adjustment device of a sewing machine, including the following specific steps:

[0066] S1. Place the fabric to be sewn above the feed dog 46 of the sewing machine;

[0067] S2. Start the second motor 26 to adjust the initial pressure;

[0068] S3. Start the first motor 14 to sew;

[0069] S4. When the fabric changes from thin to thick, the presser foot 291 rotates, the pressure rod 21 slides upward, and the second elastic member 33 and the first elastic member 25 are compressed and the pressure increases;

[0070] S5. When the fabric is relatively thick, the upward movement of the pressure rod 21 increases the pressure, causing the feed dog 46 to rise to increase the pressure and the fabric feeding depth;

[0071] S6. When the resistance on the feed dog 46 is too large due to excessive pressure on the fabric and the feed dog 46 cannot feed the fabric, the slider 12 touches the switch, and the second motor 26 rotates in the reverse direction, and the first pressing ring 23 rises and the pressure decreases.

[0072] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes should be covered within the protection scope of the present invention.

Claims

1. An adjusting device for a sewing machine, comprising a frame (1), wherein a material pressing mechanism (2), a material piercing mechanism (5), and a thread hooking mechanism (6) are arranged inside the frame (1), wherein the material pressing mechanism (2) comprises a pressing rod (21) vertically penetrating the front end of the frame (1) and sliding inside the frame (1), characterized in that: Also includes: A pressure regulating mechanism (3), the pressure regulating mechanism (3) comprising an air cylinder (31) fixedly connected to the frame (1), an inner cavity of the air cylinder (31) being provided with an adjusting ring (32), the adjusting ring (32) being capable of sliding synchronously with the pressure rod (21) and being capable of squeezing the space inside the air cylinder (31), a second elastic member (33) being provided inside the air cylinder (31), two ends of the second elastic member (33) being respectively fixedly connected to the top end of the adjusting ring (32) and the inner top of the air cylinder (31), and an outer wall of the air cylinder (31) being provided with a first exhaust hole (34) and a second exhaust hole (35); A cloth feeding mechanism (4), the cloth feeding mechanism (4) comprising a regulating box (42), two air storage boxes (44) being arranged inside the regulating box (42), a pressure block (441) being arranged inside each air storage box (44) and moving according to the air pressure inside the air storage box (44), one end of each pressure block (441) being rotatably connected to a support plate (442), one end of the two support plates (442) being away from the pressure block (441) being commonly connected to a top block (443), the two support plates (442) being rotatably connected to the regulating box (42), each air storage box (44) being provided with an air inlet hole, and the two air inlet holes being connected to the second air outlet hole (35) via a three-way hose; The side wall of the adjustment box (42) is fixedly connected to the tooth frame (41), a limiting groove (421) is provided on a side of the adjustment box (42) away from the tooth frame (41), the inner bottom of the adjustment box (42) is fixedly connected to the support column (43), the outer wall of the support column (43) is slidably connected to a fixing member (45), the front end of the fixing member (45) passes through the limiting groove (421) and is fixedly connected to the feed tooth (46), and the bottom of the fixing member (45) is in contact with the top block (443); When the thickness of the fabric increases slightly, the pressure rod (21) moves upward to drive the adjusting ring (32) upward, so that the gas inside the air cylinder (31) is squeezed and discharged through the first exhaust hole (34). At the same time, the pressure on the compressed fabric by the second elastic member (33) increases. When the thickness of the fabric increases significantly, the pressure rod (21) moves upward to drive the adjusting ring (32) upward. When the height of the adjusting ring (32) rises to above the first exhaust hole (34), the squeezed gas enters the interior of the air storage box (44) through the second exhaust hole (35) and the three-way hose. The pressure inside the air storage box (44) increases, so that the pressure block (441) slides downward inside the air storage box (44), and drives the support plate (442) to rotate on the side wall of the adjusting box (42), so that the top block (443) rises, thereby raising the feed dog (46) and increasing the depth of fabric feeding.

2. The adjusting device for a sewing machine according to claim 1, characterized in that: The outer wall of the pressure rod (21) is sleeved with a threaded sleeve (22), the outer wall of the threaded sleeve (22) is threadedly connected with a first pressure ring (23), a guide groove is provided inside the first pressure ring (23), the outer wall of the pressure rod (21) is provided with a second pressure ring (24) for clamping the pressure rod (21), the outer wall of the threaded sleeve (22) is sleeved with a first elastic member (25), the two ends of the first elastic member (25) are respectively connected to the bottom end of the first pressure ring (23) and the top end of the second pressure ring (24), the upper end of the frame (1) is fixedly connected with a second motor (26), the output end of the second motor (26) is fixedly connected with a driving wheel (27), the driving wheel (27) is meshed with a driven wheel (28), the driven wheel (28) is fixedly connected with one end of the threaded sleeve (22), one end of the pressure rod (21) extending out of the frame (1) is fixedly connected with a presser foot frame (29), and the bottom end of the presser foot frame (29) is rotatably connected with a presser foot (291).

3. The adjusting device for a sewing machine according to claim 2, characterized in that: The material-piercing mechanism (5) comprises a needle rod (51) vertically penetrating the front end of the frame (1) and sliding inside the frame (1); the outer wall of the needle rod (51) is fixedly connected to a fixing ring (52); the side wall of the fixing ring (52) is fixedly connected to a push rod (521); and the side wall of the fixing ring (52) is rotatably connected to a first connecting rod (53) via an axis.

4. The adjusting device for a sewing machine according to claim 3, characterized in that: A guide groove (11) is provided in the frame (1), a switch is provided on the top side wall of the guide groove (11), a slider (12) is slidably connected to the inner wall of the guide groove (11), a spring is provided in the inner cavity of the guide groove (11), and two ends of the spring are respectively fixedly connected to the bottom surface of the slider (12) and the inner bottom surface of the guide groove (11).

5. The adjusting device for a sewing machine according to claim 4, characterized in that: An upper shaft (13) is provided in the inner cavity of the frame (1), a first motor (14) is fixedly connected to the rear end of the frame (1), an output end of the first motor (14) is fixedly connected to the upper shaft (13), and an end of the upper shaft (13) away from the first motor (14) is eccentrically rotatably connected to the first connecting rod (53).

6. The adjusting device for a sewing machine according to claim 5, characterized in that: A tooth lifting shaft (15) is provided at the bottom of the frame (1), one end of the tooth lifting shaft (15) is slidably connected to a lower shaft crank (16), one end of the tooth lifting shaft (15) away from the lower shaft crank (16) is slidably connected to the tooth frame (41), one end of the lower shaft crank (16) is rotatably connected to a tooth lifting connecting rod (151), and one end of the tooth lifting connecting rod (151) away from the lower shaft crank (16) is rotatably connected to the upper shaft (13).

7. The adjusting device for a sewing machine according to claim 6, characterized in that: A cloth feed shaft (17) is arranged in the frame (1), one end of the cloth feed shaft (17) is rotatably connected to an end of the tooth frame (41) away from the tooth lifting shaft (15), and the end of the cloth feed shaft (17) away from the tooth frame (41) is rotatably connected to a cloth feed connecting rod (171), and the cloth feed connecting rod (171) is slidably connected to the upper shaft (13).

8. The adjusting device for a sewing machine according to claim 7, characterized in that: The thread hooking mechanism (6) comprises a lower shaft (61), one end of the lower shaft (61) close to the tooth frame (41) is provided with a shuttle holder (62), the shuttle holder (62) is fixedly connected to the frame (1), a shuttle (621) is embedded in the shuttle holder (62), one end of the lower shaft (61) away from the shuttle holder (62) is slidably connected to the lower shaft crank (16), and a shuttle core (622) is rotatably connected inside the shuttle (621).

9. A method for adjusting a sewing machine adjusting device, using the sewing machine adjusting device according to claim 8, characterized in that: The following steps are involved: S1. Place the fabric to be sewn above the feed dog (46) of the sewing machine; S2. Start the second motor (26) to adjust the initial pressure; S3. Starting the first motor (14) for sewing; S4. When the fabric changes from thin to thick, the presser foot (291) rotates, the pressure rod (21) slides upward, and the second elastic member (33) and the first elastic member (25) are compressed and the pressure increases; S5. When the fabric thickness is large, the pressure of the pressure rod (21) increases, causing the feed dog (46) to rise and increase the pressure, thereby increasing the depth of the fabric; S6. When the cloth is subjected to excessive pressure and the resistance of the cloth feeding dog (46) is too great to feed the cloth, the slider (12) touches the switch, the second motor (26) rotates in the reverse direction, and the upward pressure of the first pressure ring (23) decreases.

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