Pressure foot lifting air suction thread clamping device of flat seaming machine

Abstract

The invention discloses a flat seaming machine presser foot lifting air suction thread clamping device and aims to provide a flat seaming machine presser foot lifting air suction thread clamping device which is simple in structure and convenient to manufacture. The presser foot lifting air suction thread clamping device of the flat seaming machine can effectively solve the problem that after the flat seaming machine cuts threads every time, when sewing is started next time, due to the fact that the thread clamping force of upper threads is insufficient, the sewing is prone to loosing. The device comprises a fixed part which is fixedly arranged on a machine head of the flat seaming machine and comprises a fixed thread pressing part which is located between a sewing needle and a presser foot rod of the flat seaming machine; the air suction pipe comprises an air suction port which is located between the sewing needle and the fixed thread pressing part; the elastic element is arranged on the fixed part and comprises an elastic arm and a thread pressing part arranged on the elastic arm, the thread pressing part and the sewing needle are located on the same side of the fixed thread pressing part, and the thread pressing part abuts against the fixed thread pressing part under the action of the elastic arm; the push plate is fixed on the presser foot rod; when the presser foot rod drives the presser foot to ascend, the push plate abuts against the elastic arm and enables the line pressing piece to be separated from the fixed line pressing part.

Description

Technical Field

[0001] This invention relates to the field of cover-up sewing machine technology, and more specifically to a cover-up sewing machine presser foot suction and thread clamping device. Background Technology

[0002] After a coverstitch machine finishes sewing a piece of fabric, the top thread needs to be cut to prepare for sewing the next product. Currently, after each thread cut, the top thread is not held in place enough when starting to sew again, making it difficult to thread properly and causing the thread to come loose at the start of the next stitch, especially when starting to sew without a sewing machine.

[0003] For example, Chinese Patent Publication No. CN221918499U describes an invention entitled "A Coverstitching Machine," which includes a machine body with a sewing needle; an assembly plate mounted on the machine body with an opening below the sewing needle; two shears (one and two pieces) and a drive assembly. The shears are assembled within the assembly plate, with the shears located on opposite sidewalls of the opening in the assembly plate. The drive assembly drives the shears to move in opposite directions. This invention aims to solve the problem of inconvenient manual thread cutting; however, it also suffers from the problem of thread slippage during the next sewing attempt after each thread cut due to insufficient thread clamping force. Summary of the Invention

[0004] The purpose of this invention is to provide a simple and easy-to-manufacture overlock sewing machine with a presser foot suction and thread clamping device that effectively solves the problem of thread slippage during the next sewing start due to insufficient thread clamping force after each thread cut.

[0005] The technical solution of this invention is: A presser foot lifting suction thread clamping device for a coverstitch sewing machine includes: The fixing component is fixedly installed on the head of the cover-sewing machine, including the fixed pressure part, which is located between the needle and the presser foot bar of the cover-sewing machine; The suction tube includes a suction port, which is located between the suture needle and the fixed suture part, and the suction port is close to or close to the fixed suture part. An elastic element is provided on a fixed member, including an elastic arm and a suture piece provided on the elastic arm. The suture piece and the sewing needle are located on the same side of the fixed suture part. The suture piece is pressed against the fixed suture part under the action of the elastic arm. At this time, the suture piece is located below the air intake. The push plate is fixed to the presser foot rod; as the presser foot rod moves the presser foot upward, the push plate abuts against the elastic arm, separating the stitching component from the fixed stitching part. The specific operation of this overlock sewing machine presser foot lifting suction thread clamping device is as follows: After one sewing cycle of the coverstitch machine is completed and the top thread is cut (at this time, the presser foot is pressing on the fabric on the table of the coverstitch machine); then, the presser foot is raised by the presser foot lever. During this process, the presser foot lever drives the push plate to rise synchronously. As the push plate rises, it will press against the elastic arm and drive the elastic arm to rotate upward, so that the quilting part is separated from the fixed quilting part; when the presser foot rises to the highest position, the air pipe is turned on to suck in air, and the free end of the top thread hanging down is sucked into the air pipe through the air port.

[0006] Before the next stitch begins on the coverstitch machine, when the presser foot lever lowers the presser foot to its lowest position, the push plate separates from the elastic arm. The quilling element, under the action of the elastic arm, presses against the fixed quilling part, simultaneously pressing the top thread firmly against the fixed quilling part. Then, the suction pipe stops suction. Thus, one free end of the top thread is pressed between the quilling element and the fixed quilling part. When the coverstitch machine begins stitching again, the clamping force on the top thread is sufficient, and the top thread has tension, enabling the formation of a complete stitch and preventing thread slippage during stitching. This solution provides a presser foot lifting suction thread clamping device for coverstitch machines. By utilizing the lifting and lowering movement of the presser foot lever, the quilling element is separated from the fixed quilling part or pressed against the fixed quilling part under the action of the elastic arm. This achieves this without affecting the normal operation of the coverstitch machine, and eliminates the need for an additional power component to drive the quilling element, simplifying the device structure and making it simple to manufacture, thus reducing production costs.

[0007] Preferably, the elastic element is a torsion spring. A axial screw is fixed to the fixing member, and the torsion spring is sleeved on the axial screw. One end of the torsion spring abuts against the fixing member, and the other end extends downward to form the elastic arm. A pressure piece is located at the end of the elastic arm. Using a torsion spring as the elastic element makes it easy to obtain, facilitates actual production, and reduces manufacturing costs.

[0008] Preferably, the elastic element is composed of an elastic sheet, with the upper end of the elastic sheet fixed to the fixing member, and the lower end of the elastic sheet extending downward to form the elastic arm, with a pressure wire member located at the end of the elastic arm. Using an elastic sheet as the elastic element results in a simple structure and convenient manufacturing.

[0009] Preferably, the pusher plate includes a pushing part located between the presser foot bar and the fixed quilting part. When the presser foot bar drives the presser foot to rise, the pushing part abuts against the elastic arm and separates the quilting part from the fixed quilting part. This design arranges the pushing part of the pusher plate between the presser foot bar and the fixed quilting part, providing sufficient space for the pushing part and not affecting the normal operation of other existing components of the overlock sewing machine.

[0010] Preferably, the elastic arm extends at an angle, with its lower part tilting towards the needle. The upper part of the elastic arm and the push plate are located on the same side of the fixed pressure part, and the push part and the fixed pressure part are located on opposite sides of the upper part of the elastic arm. This arrangement of the elastic arm facilitates the placement of the push plate and the elastic arm, avoiding interference with the normal operation of other existing components of the coverstitch machine.

[0011] Preferably, the fixed quilting part is located above and near the presser foot of the overlock sewing machine.

[0012] Preferably, the suction tube is fixed to the fixing member. In this way, the relative position between the suction port of the suction tube and the fixed pressure part can be kept stable, and when the suction tube is turned on, the free end of the face thread hanging down can be stably sucked into the suction tube through the suction port.

[0013] Preferably, the fastener is fixedly connected to the head of the overlock sewing machine by bolts. This facilitates the installation and removal of the fastener, allowing the overlock sewing machine's presser foot suction thread clamping device to be easily added to existing overlock sewing machines.

[0014] Preferably, the fastener includes a fixing plate and a mounting plate. The fixing plate is fixedly connected to the head of the overlock sewing machine by bolts. The mounting plate is connected to the fixing plate by bolts. The lower part of the mounting plate extends downward to form a pressure plate, which is located above and close to the presser foot of the overlock sewing machine. The pressure plate constitutes the fixed pressure plate part. This facilitates the actual processing and manufacturing of the fastener.

[0015] Preferably, the push plate is bolted to the presser foot rod. This facilitates the installation and removal of the push plate, allowing the presser foot lifting suction thread clamping device to be easily added to existing overlock sewing machines.

[0016] The beneficial effects of this invention are: Firstly, when starting a stitch with a coverstitch machine, the tension of the thread can be sufficient, and the thread will be under tension, which can form a complete stitch and avoid the problem of the thread coming loose.

[0017] Secondly, the lifting and lowering movement of the presser foot lever of the cover-sewing machine can be used to separate the presser part from the fixed presser part, or press it against the fixed presser part under the action of the elastic arm. On the one hand, it will not affect the normal operation of the cover-sewing machine, and on the other hand, there is no need for an additional power component to drive the presser part, which simplifies the device structure and reduces the manufacturing cost. Attached Figure Description

[0018] Figure 1 This is a three-dimensional partial structural schematic diagram of one embodiment of the presser foot suction thread clamping device for a cover-sewing machine according to the present invention.

[0019] Figure 2 yes Figure 1 A magnified view of a portion of point A in the middle.

[0020] Figure 3 This is a partial structural schematic diagram of a thread clamping device for lifting the presser foot of a cover-sewing machine according to the present invention.

[0021] Figure 4 This is a partial front view of one embodiment of a presser foot suction and thread clamping device for a cover-stitching machine according to the present invention.

[0022] Figure 5 This is a partial front view of another embodiment of the presser foot suction and thread clamping device for a cover-sewing machine according to the present invention.

[0023] In the picture: Inhalation tube 1, inhalation port 1.1; 2. Elastic element; 2.1. Elastic arm; 2.2. Pressure wire component; Push plate 3, pusher part 3.1; Presser foot lever 4; 5 stitches; Presser foot 6; Nose 7; Fastener 8, fixing crimping part 8.0, fixing plate 8.1, mounting plate 8.2; Shaft screw 9; 10. Noodles. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Specific Implementation Example 1, such as Figures 1-4 As shown, a presser foot lifting suction thread clamping device for a cover stitch machine includes a fixing member 8, a suction pipe 1, an elastic element 2, and a push plate 3.

[0025] The fixing member 8 is fixedly mounted on the head 7 of the coverstitch machine. For example, the fixing member 8 is fixedly mounted on the outer shell of the head 7 of the coverstitch machine, or on the frame structure of the head 7 of the coverstitch machine. The fixing member 8 includes a fixed pressure thread portion 8.0. The fixed pressure thread portion 8.0 is located between the sewing needle 5 and the presser foot bar 4 of the coverstitch machine. In this embodiment, the fixed pressure thread portion 8.0 is located above and close to the presser foot 6 of the coverstitch machine.

[0026] The suction tube 1 includes a suction port 1.1, which is arranged downwards. The suction port 1.1 and the sewing needle 5 are located on the same side of the fixed quilting part 8.0. The suction port 1.1 is located between the sewing needle 5 and the fixed quilting part 8.0, and the suction port 1.1 is close to or against the fixed quilting part 8.0.

[0027] In one example, the air intake 1.1 is located close to the side of the fixed pressure line portion 8.0.

[0028] In another example, there is a gap between the air intake 1.1 and the fixed pressure line portion 8.0, and the air intake 1.1 is close to the side of the fixed pressure line portion 8.0.

[0029] The inhalation power source for inhalation tube 1 can be configured as needed. Specifically, In one example, one end of the suction tube 1 is connected to a suction pump via a pipe. By controlling the operation of the suction pump, a suction effect is generated in the suction tube 1 and the suction port 1.1.

[0030] In another example, one end of the suction pipe 1 is connected to an exhaust fan via a pipe. By controlling the operation of the exhaust fan, a suction effect is generated within the suction pipe 1 and the suction port 1.1.

[0031] In the third example, one end of the suction pipe 1 is connected to a negative pressure source via a pipe, for example, one end of the suction pipe 1 is connected to a negative pressure pipeline in the factory via a pipe, which is equipped with an automatically controlled switching valve, such as a solenoid valve. By controlling the opening and closing of the switching valve, the suction effect is controlled within the suction pipe 1 and the suction port 1.1.

[0032] The elastic element 2 is mounted on the fixing member 8. The elastic element 2 includes an elastic arm 2.1 and a suture presser 2.2 mounted on the elastic arm 2.1. The suture presser 2.2 and the sewing needle 5 are located on the same side of the fixed suture part 8.0, between the sewing needle 5 and the fixed suture part 8.0. Under the action of the elastic arm 2.1, the suture presser 2.2 presses against the fixed suture part 8.0. At this time, the suture presser 2.2 is located below the air intake 1.1. The suture presser 2.2 is close to the air intake 1.1. The specific structure of the elastic element 2 in this embodiment is as follows: The elastic element 2 is a torsion spring. A shaft screw 9 is fixed to the fixing member 8. The shaft screw 9 is bolted into a threaded hole on the fixing member 8. The torsion spring is sleeved on the shaft screw 9. One end of the torsion spring abuts against the fixing member 8; specifically, one end of the torsion spring extends upwards and abuts against the support member of the fixing member 8. The other end of the torsion spring extends downwards to form the elastic arm 2.1. A pressure member 2.2 is located at the end of the elastic arm 2.1. In this embodiment, the pressure member 2.2 is a pressure rod, and the elastic arm 2.1 and the pressure member 2.2 are integrally bent and formed. Using a torsion spring as the elastic element 2 makes it easy to obtain, facilitates actual production, and reduces manufacturing costs.

[0033] In one example, both ends of the torsion spring are n-shaped, and each end of the torsion spring has two spring arms, i.e., a connecting crossbar connecting the ends of the two spring arms. The two spring arms extending downwards in the torsion spring constitute the elastic arm 2.1, the fixed pressure part 8.0 is located between the two spring arms extending downwards in the torsion spring, and the connecting crossbar extending downwards in the torsion spring constitutes the pressure part 2.2.

[0034] In another example, the torsion spring has only one spring arm at each end.

[0035] The push plate 3 is fixed to the presser foot rod 4.

[0036] As the presser foot lever 4 drives the presser foot 6 to rise, the push plate 3 presses against the elastic arm 2.1 and separates the pressing part 2.2 from the fixed pressing part 8.0.

[0037] When the presser foot lever 4 drives the presser foot 6 to descend to the lowest position, the push plate 3 separates from the elastic arm 2.1, and the pressing part 2.2 presses against the fixed pressing part 8.0 under the action of the elastic arm 2.1.

[0038] When the presser foot lever 4 drives the presser foot 6 to rise to the highest position, the push plate 3 abuts against the elastic arm 2.1 and separates the pressing part 2.2 from the fixed pressing part 8.0.

[0039] The specific operation of the overlock sewing machine presser foot lifting suction thread clamping device in this embodiment is as follows: After one sewing cycle of the coverstitch machine is completed, the top thread 10 is cut (at this time, the presser foot 6 is pressed down on the fabric on the table of the coverstitch machine); then, the presser foot 6 is raised by the presser foot lever 4. During this process, the presser foot lever 4 drives the push plate 3 to rise synchronously. During the rise of the push plate 3, it will press against the elastic arm 2.1 and drive the elastic arm 2.1 to rotate upward, so that the quilting part 2.2 is separated from the fixed quilting part 8.0; when the presser foot 6 rises to the highest position, the suction pipe 1 starts to suck air, and sucks the free end of the top thread 10 hanging freely into the suction pipe 1 through the suction port 1.1.

[0040] Before the next stitching start of the coverstitch machine, when the presser foot lever 4 drives the presser foot 6 to the lowest position, the push plate 3 separates from the elastic arm 2.1, and the quilting element 2.2 presses against the fixed quilting part 8.0 under the action of the elastic arm 2.1. At the same time, the quilting element 2.2 presses the top thread 10 tightly against the fixed quilting part 8.0. Then the suction pipe 1 stops suctioning. In this way, one side of the free end of the top thread 10 is pressed between the quilting element 2.2 and the fixed quilting part 8.0. When the coverstitch machine starts stitching again, the clamping force of the top thread 10 is sufficient, and the top thread 10 has tension, which can form a complete stitch and avoid the problem of stitching detachment. This solution provides a presser foot lifting suction thread clamping device for a coverstitch sewing machine. By utilizing the lifting and lowering motion of the presser foot lever 4 of the coverstitch sewing machine, the thread clamping component 2.2 can be separated from the fixed thread clamping part 8.0, or pressed against the fixed thread clamping part 8.0 under the action of the elastic arm 2.1. Thus, on the one hand, it does not affect the normal operation of the coverstitch sewing machine; on the other hand, it eliminates the need for an additional power component to drive the thread clamping component 2.2, simplifying the device structure. This makes the presser foot lifting suction thread clamping device for coverstitch sewing machines simple in structure, easy to manufacture, and reduces manufacturing costs.

[0041] Furthermore, such as Figure 2 , Figure 4 As shown, the push plate 3 includes a pushing part 3.1, which is located between the presser foot rod 4 and the fixed quilting part 8.0. When the presser foot rod 4 drives the presser foot 6 to rise, the pushing part 3.1 abuts against the elastic arm 2.1 and separates the quilting part 2.2 from the fixed quilting part 8.0. In this embodiment, the pushing part 3.1 of the push plate 3 is arranged between the presser foot rod 4 and the fixed quilting part 8.0, so that the pushing part 3.1 has sufficient space for arrangement and will not affect the normal operation of other original components of the overlock sewing machine.

[0042] In this embodiment, the push plate 3 also includes the connecting part, which is formed by bending the same steel plate as the pushing part 3.1. The pushing part 3.1 is arranged at an angle, and the lower end of the pushing part 3.1 is inclined toward the side of the needle 5.

[0043] Furthermore, such as Figures 2-4 As shown, the elastic arm 2.1 extends vertically at an angle, with its lower part tilting towards the needle 5. The upper part of the elastic arm 2.1 is located on the same side as the push plate 3 and the fixed pressure part 8.0, and the push part 3.1 and the fixed pressure part 8.0 are located on opposite sides of the upper part of the elastic arm 2.1. The arrangement structure of the elastic arm 2.1 in this embodiment facilitates the arrangement of the push plate 3 and the elastic arm 2.1, avoiding interference with the normal operation of other original components of the coverstitch machine.

[0044] Furthermore, the suction tube 1 is fixed to the fixing member 8. In this way, the relative position of the suction port 1.1 of the suction tube 1 and the fixed pressure part 8.0 can be kept stable, and when the suction tube 1 is opened for suction, the free end of the face line 10 that hangs freely can be stably sucked into the suction tube 1 through the suction port 1.1.

[0045] In one example, the suction pipe 1 is fixed to the fastener 8 by welding. This facilitates the fixation of the suction pipe 1 to the fastener 8.

[0046] In another example, the suction tube 1 is fixed to the fastener 8 by bolts, rivets, or clamps. This facilitates the fixation of the suction tube 1 to the fastener 8.

[0047] Furthermore, the fixing component 8 is fixedly connected to the head 7 of the overlock sewing machine by bolts. This facilitates the installation and removal of the fixing component 8, allowing the overlock sewing machine's presser foot suction thread clamping device to be easily added to existing overlock sewing machines.

[0048] In one implementation, such as Figure 2 , Figure 3As shown, the fastener 8 includes a fixing plate 8.1 and a mounting plate 8.2. The fixing plate 8.1 is fixedly connected to the head 7 of the overlock sewing machine by bolts. The mounting plate 8.2 is connected to the fixing plate 8.1 by bolts. The lower part of the mounting plate 8.2 extends downward to form a pressure plate. The pressure plate is located above and close to the presser foot 6 of the overlock sewing machine, and the pressure plate constitutes the fixed pressure part 8.0. In this way, the construction of the fastener 8 is facilitated, and interference between the fastener 8 and other components on the existing overlock sewing machine is avoided.

[0049] In another embodiment, the fastener 8 includes a fixing plate 8.1 and a mounting plate 8.2. The fixing plate 8.1 and the mounting plate 8.2 are formed by bending the same piece of steel plate. This facilitates the actual processing and manufacturing of the fastener 8.

[0050] Furthermore, the push plate 3 is bolted to the presser foot rod 4. This facilitates the installation and removal of the push plate 3, allowing the presser foot lifting suction thread clamping device to be easily added to existing overlock sewing machines. Of course, the push plate 3 can also be fixedly connected to the presser foot rod 4 by welding or riveting.

[0051] Specific embodiment two, such as Figure 1 , Figure 5 As shown, a presser foot lifting suction thread clamping device for a cover stitch machine includes a fixing member 8, a suction pipe 1, an elastic element 2, and a push plate 3.

[0052] The fixing member 8 is fixedly mounted on the head 7 of the coverstitch machine. For example, the fixing member 8 is fixedly mounted on the outer shell of the head 7 of the coverstitch machine, or on the frame structure of the head 7 of the coverstitch machine. The fixing member 8 includes a fixed pressure thread portion 8.0. The fixed pressure thread portion 8.0 is located between the sewing needle 5 and the presser foot bar 4 of the coverstitch machine. In this embodiment, the fixed pressure thread portion 8.0 is located above and close to the presser foot 6 of the coverstitch machine.

[0053] The suction tube 1 includes a suction port 1.1, which is arranged downwards. The suction port 1.1 and the sewing needle 5 are located on the same side of the fixed quilting part 8.0. The suction port 1.1 is located between the sewing needle 5 and the fixed quilting part 8.0, and the suction port 1.1 is close to or against the fixed quilting part 8.0.

[0054] In one example, the air intake 1.1 is located close to the side of the fixed pressure line portion 8.0.

[0055] In another example, there is a gap between the air intake 1.1 and the fixed pressure line portion 8.0, and the air intake 1.1 is close to the side of the fixed pressure line portion 8.0.

[0056] The inhalation power source for inhalation tube 1 can be configured as needed. Specifically, In one example, one end of the suction tube 1 is connected to a suction pump via a pipe. By controlling the operation of the suction pump, a suction effect is generated in the suction tube 1 and the suction port 1.1.

[0057] In another example, one end of the suction pipe 1 is connected to an exhaust fan via a pipe. By controlling the operation of the exhaust fan, a suction effect is generated within the suction pipe 1 and the suction port 1.1.

[0058] In the third example, one end of the suction pipe 1 is connected to a negative pressure source via a pipe, for example, one end of the suction pipe 1 is connected to a negative pressure pipeline in the factory via a pipe, which is equipped with an automatically controlled switching valve, such as a solenoid valve. By controlling the opening and closing of the switching valve, the suction effect is controlled within the suction pipe 1 and the suction port 1.1.

[0059] The elastic element 2 is mounted on the fixing member 8. The elastic element 2 includes an elastic arm 2.1 and a suture presser 2.2 mounted on the elastic arm 2.1. The suture presser 2.2 and the sewing needle 5 are located on the same side of the fixed suture part 8.0, between the sewing needle 5 and the fixed suture part 8.0. Under the action of the elastic arm 2.1, the suture presser 2.2 presses against the fixed suture part 8.0. At this time, the suture presser 2.2 is located below the air intake 1.1. The suture presser 2.2 is close to the air intake 1.1. The specific structure of the elastic element 2 in this embodiment is as follows: In another embodiment, the elastic element 2 is composed of an elastic sheet. The upper end of the elastic sheet is fixed to the fixing member 8, and the lower end of the elastic sheet extends downward to form the elastic arm 2.1. The pressure piece 2.2 is fixedly disposed at the end of the elastic arm 2.1. In this embodiment, the pressure piece 2.2 is a pressure sheet. Using an elastic sheet as the elastic element 2 has a simple structure and is easy to manufacture.

[0060] In another embodiment, the elastic element 2 includes a mounting part and a spring rod. The mounting part is fixed to the fixing member 8, the upper end of the spring rod is fixed to the mounting part, and the lower end of the spring rod extends downward to form the elastic arm 2.1. The wire pressing member 2.2 is a wire pressing rod, which is fixedly disposed at the end of the elastic arm 2.1. In this embodiment, the wire pressing member 2.2 is made of a mounting part and a spring rod, which has a simple structure and is easy to manufacture.

[0061] The push plate 3 is fixed to the presser foot rod 4.

[0062] As the presser foot lever 4 drives the presser foot 6 to rise, the push plate 3 presses against the elastic arm 2.1 and separates the pressing part 2.2 from the fixed pressing part 8.0.

[0063] When the presser foot lever 4 drives the presser foot 6 to descend to the lowest position, the push plate 3 separates from the elastic arm 2.1, and the pressing part 2.2 presses against the fixed pressing part 8.0 under the action of the elastic arm 2.1.

[0064] When the presser foot lever 4 drives the presser foot 6 to rise to the highest position, the push plate 3 abuts against the elastic arm 2.1 and separates the pressing part 2.2 from the fixed pressing part 8.0.

[0065] The specific operation of the overlock sewing machine presser foot lifting suction thread clamping device in this embodiment is as follows: After one sewing cycle of the coverstitch machine is completed, the top thread 10 is cut (at this time, the presser foot 6 is pressed down on the fabric on the table of the coverstitch machine); then, the presser foot 6 is raised by the presser foot lever 4. During this process, the presser foot lever 4 drives the push plate 3 to rise synchronously. During the rise of the push plate 3, it will press against the elastic arm 2.1 and drive the elastic arm 2.1 to rotate upward, so that the quilting part 2.2 is separated from the fixed quilting part 8.0; when the presser foot 6 rises to the highest position, the suction pipe 1 starts to suck air, and sucks the free end of the top thread 10 hanging freely into the suction pipe 1 through the suction port 1.1.

[0066] Before the next stitching start of the coverstitch machine, when the presser foot lever 4 drives the presser foot 6 to the lowest position, the push plate 3 separates from the elastic arm 2.1, and the quilting element 2.2 presses against the fixed quilting part 8.0 under the action of the elastic arm 2.1. At the same time, the quilting element 2.2 presses the top thread 10 tightly against the fixed quilting part 8.0. Then the suction pipe 1 stops suctioning. In this way, one side of the free end of the top thread 10 is pressed between the quilting element 2.2 and the fixed quilting part 8.0. When the coverstitch machine starts stitching again, the clamping force of the top thread 10 is sufficient, and the top thread 10 has tension, which can form a complete stitch and avoid the problem of stitching detachment. This solution provides a presser foot lifting suction thread clamping device for a coverstitch sewing machine. By utilizing the lifting and lowering motion of the presser foot lever 4 of the coverstitch sewing machine, the thread clamping component 2.2 can be separated from the fixed thread clamping part 8.0, or pressed against the fixed thread clamping part 8.0 under the action of the elastic arm 2.1. Thus, on the one hand, it does not affect the normal operation of the coverstitch sewing machine; on the other hand, it eliminates the need for an additional power component to drive the thread clamping component 2.2, simplifying the device structure. This makes the presser foot lifting suction thread clamping device for coverstitch sewing machines simple in structure, easy to manufacture, and reduces manufacturing costs.

[0067] Furthermore, such as Figure 5 As shown, the push plate 3 includes a pushing part 3.1, which is located between the presser foot rod 4 and the fixed quilting part 8.0. When the presser foot rod 4 drives the presser foot 6 to rise, the pushing part 3.1 abuts against the elastic arm 2.1 and separates the quilting part 2.2 from the fixed quilting part 8.0. In this embodiment, the pushing part 3.1 of the push plate 3 is arranged between the presser foot rod 4 and the fixed quilting part 8.0, so that the pushing part 3.1 has sufficient space for arrangement and will not affect the normal operation of other original components of the overlock sewing machine.

[0068] In this embodiment, the push plate 3 includes the connecting part, which is formed by bending the same steel plate as the pushing part 3.1. The pushing part 3.1 is arranged at an angle, and the lower end of the pushing part 3.1 is inclined towards the side of the needle 5.

[0069] Furthermore, such as Figure 5 As shown, the elastic arm 2.1 extends vertically at an angle, with its lower part tilting towards the needle 5. The upper part of the elastic arm 2.1 is located on the same side as the push plate 3 and the fixed pressure part 8.0, and the push part 3.1 and the fixed pressure part 8.0 are located on opposite sides of the upper part of the elastic arm 2.1. The arrangement structure of the elastic arm 2.1 in this embodiment facilitates the arrangement of the push plate 3 and the elastic arm 2.1, avoiding interference with the normal operation of other original components of the coverstitch machine.

[0070] Furthermore, the suction tube 1 is fixed to the fixing member 8. In this way, the relative position of the suction port 1.1 of the suction tube 1 and the fixed pressure part 8.0 can be kept stable, and when the suction tube 1 is opened for suction, the free end of the face line 10 that hangs freely can be stably sucked into the suction tube 1 through the suction port 1.1.

[0071] In one example, the suction pipe 1 is fixed to the fastener 8 by welding. This facilitates the fixation of the suction pipe 1 to the fastener 8.

[0072] In another example, the suction tube 1 is fixed to the fastener 8 by bolts, rivets, or clamps. This facilitates the fixation of the suction tube 1 to the fastener 8.

[0073] Furthermore, the fixing component 8 is fixedly connected to the head 7 of the overlock sewing machine by bolts. This facilitates the installation and removal of the fixing component 8, allowing the overlock sewing machine's presser foot suction thread clamping device to be easily added to existing overlock sewing machines.

[0074] In one embodiment, the fastener 8 includes a fixing plate 8.1 and a mounting plate 8.2. The fixing plate 8.1 is fixedly connected to the head 7 of the overlock sewing machine by bolts. The mounting plate 8.2 is connected to the fixing plate 8.1 by bolts. The lower part of the mounting plate 8.2 extends downward to form a pressure plate. The pressure plate is located above and close to the presser foot 6 of the overlock sewing machine, and the pressure plate constitutes the fixed pressure plate part 8.0. In this way, the construction of the fastener 8 is facilitated, and interference between the fastener 8 and other components on the existing overlock sewing machine is avoided.

[0075] In another embodiment, the fastener 8 includes a fixing plate 8.1 and a mounting plate 8.2. The fixing plate 8.1 and the mounting plate 8.2 are formed by bending the same piece of steel plate. This facilitates the actual processing and manufacturing of the fastener 8.

[0076] Furthermore, the push plate 3 is bolted to the presser foot rod 4. This facilitates the installation and removal of the push plate 3, allowing the presser foot lifting suction thread clamping device to be easily added to existing overlock sewing machines. Of course, the push plate 3 can also be fixedly connected to the presser foot rod 4 by welding or riveting.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A presser foot lifting suction thread clamping device for a coverstitch sewing machine, characterized in that, include: The fixing component is fixedly installed on the head of the cover-sewing machine, including the fixed pressure part, which is located between the needle and the presser foot bar of the cover-sewing machine; The suction tube includes a suction port, which is located between the suture needle and the fixed suture part, and the suction port is close to or close to the fixed suture part. An elastic element is provided on a fixed member, including an elastic arm and a suture piece provided on the elastic arm. The suture piece and the sewing needle are located on the same side of the fixed suture part. The suture piece is pressed against the fixed suture part under the action of the elastic arm. At this time, the suture piece is located below the air intake. The push plate is fixed to the presser foot rod; when the presser foot rod drives the presser foot to rise, the push plate presses against the elastic arm and separates the pressing part from the fixed pressing part.

2. The overlock sewing machine presser foot lifting suction thread clamping device according to claim 1, characterized in that, The elastic element is a torsion spring. A shaft screw is fixed on the fixing member. The torsion spring is sleeved on the shaft screw. One end of the torsion spring abuts against the fixing member. The other end of the torsion spring extends downward to form the elastic arm. The pressure wire member is located at the end of the elastic arm.

3. The overlock sewing machine presser foot suction thread clamping device according to claim 1, characterized in that, The elastic element is composed of an elastic sheet, the upper end of which is fixed to a fixing member, and the lower end of which extends downward to form the elastic arm. A pressure wire member is provided at the end of the elastic arm.

4. A presser foot lifting and suction thread clamping device for a coverstitch sewing machine according to claim 1, 2, or 3, characterized in that, The push plate includes a pushing part, which is located between the presser foot rod and the fixed pressing part. When the presser foot rod drives the presser foot to rise, the pushing part abuts against the elastic arm and separates the pressing part from the fixed pressing part.

5. The overlock sewing machine presser foot suction thread clamping device according to claim 4, characterized in that, The elastic arm extends vertically at an angle, with the lower part of the elastic arm tilting towards the needle side. The upper part of the elastic arm and the push plate are located on the same side of the fixed pressure part, and the push part and the fixed pressure part are located on opposite sides of the upper part of the elastic arm.

6. A presser foot lifting and suction thread clamping device for a coverstitch sewing machine according to claim 1, 2, or 3, characterized in that, The fixed pressure line section is located above and close to the presser foot of the overlock sewing machine.

7. A presser foot lifting and suction thread clamping device for a coverstitch sewing machine according to claim 1, 2, or 3, characterized in that, The suction pipe is fixed to the fastener.

8. A presser foot lifting and suction thread clamping device for a coverstitch sewing machine according to claim 1, 2, or 3, characterized in that, The fastener is fixedly connected to the head of the overlock sewing machine by bolts.

9. A presser foot lifting and suction thread clamping device for a coverstitch machine according to claim 8, characterized in that, The fastener includes a fixing plate and a mounting plate. The fixing plate is fixedly connected to the head of the overlock sewing machine by bolts. The mounting plate is connected to the fixing plate by bolts. The lower part of the mounting plate extends downward to form a pressure plate. The pressure plate is located above and close to the presser foot of the overlock sewing machine. The pressure plate constitutes the fixed pressure part.

10. A presser foot lifting and suction thread clamping device for a coverstitch sewing machine according to claim 1, 2, or 3, characterized in that, The push plate is bolted to the presser foot rod.

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