Thread catching structure, sewing machine and sewing control method

Abstract

The application provides a thread catching structure, a sewing machine and a sewing control method. The thread catching structure comprises a rotatable rotating shuttle in the sewing machine, a movable holding piece and a catching driving source for driving the movement of the holding piece. The rotating shuttle has a shuttle tip. The holding piece is distributed on the outer circumferential side of the rotating shuttle and is located on the lower side of the needle. A thread passing hole is formed on the holding piece. When the sewing machine sews a first needle, the catching driving source drives the movement of the holding piece to a thread catching position. The thread passing hole is located directly below the needle and allows the needle to pass through. According to the application, the holding piece can catch the free section of the thread on the side of the needle and keep it in the thread passing hole when sewing the first needle. When sewing the second needle, the holding piece can also exert a holding force on the free section of the thread. Therefore, the free section of the thread can effectively generate a thread loop during the upward movement of the needle when sewing the second needle. Thus, the shuttle tip of the rotating shuttle can smoothly hook the thread loop, thereby ensuring the stability of the stitches and effectively ensuring the sewing quality and stability.

Description

Technical Field

[0001] This invention relates to a surface line capturing structure.

[0002] The present invention also relates to a sewing machine comprising the above-described thread-catching structure.

[0003] The present invention further relates to a sewing control method using the above-described thread-catching structure. Background Technology

[0004] When a sewing machine sews fabric, the needle moves up and down reciprocally while the shuttle rotates. As the needle moves upward, the tip of the shuttle hooks onto the loops formed by the top thread, causing the top and bottom threads to interweave and create a stitch on the fabric, thus sewing together one or more layers of fabric. However, in existing sewing machines, because the top thread thread threaded through the needle has a free end, the shuttle tip may not be able to hook onto the top thread when starting a stitch, resulting in a section of empty stitch on the fabric. This leads to poor stitch quality and reduces sewing quality and stability. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a surface thread capturing structure that ensures that the tip of the rotary hook can stably hook onto the surface thread.

[0006] To achieve the above objectives, the present invention provides a top thread capturing structure, including a rotatable shuttle in a sewing machine, a movable retainer, and a capturing drive source for driving the retainer. The shuttle has a shuttle tip, and the retainer is distributed on the outer periphery of the shuttle and located below the needle in the sewing machine. The retainer has a thread-passing hole. When the sewing machine sews the first stitch, the capturing drive source drives the retainer to move to the top thread capturing position. The thread-passing hole is located directly below the needle, allowing the needle to pass through.

[0007] Furthermore, the retaining member moves by rotating around the central axis of the rotary shuttle.

[0008] Furthermore, the through hole is a circular hole or an oblong hole.

[0009] Furthermore, the sewing machine is equipped with a single-action thread-cutting mechanism, which includes a fixed blade, a rotatable active thread-cutting blade, and a thread-cutting drive source that is connected to the active thread-cutting blade. The retaining member is the active thread-cutting blade, and the capturing drive source is the thread-cutting drive source.

[0010] Furthermore, the active tangent is provided with a first tangent cutting edge; along the retraction rotation direction of the active tangent, the first tangent cutting edge and the through hole are distributed sequentially on the rotation path of the active tangent.

[0011] Furthermore, the sewing machine is equipped with a double-moving-blade thread-cutting mechanism, which includes a rotatable active thread cutter and an auxiliary moving thread cutter, and a thread-cutting drive source that is pulsatorically connected to both the active and auxiliary moving thread cutters. The retaining member is either the active or auxiliary moving thread cutter, and the capturing drive source is a thread-cutting drive source.

[0012] Furthermore, the active tangent is provided with a first tangent cutting edge, and the auxiliary active tangent is provided with a second tangent cutting edge;

[0013] When the retainer is an active tangent, the first tangent cutting edge and the through hole are distributed sequentially along the rotation path of the active tangent in the direction of its retraction rotation.

[0014] When the retainer is an auxiliary moving tangent, the second tangent cutting edge and the through hole are distributed sequentially along the rotation path of the auxiliary moving tangent in the direction of its retraction rotation.

[0015] This application also provides a sewing machine equipped with the thread-catching structure described above.

[0016] This application further provides a sewing control method using the thread-catching structure described above, the sewing control method comprising the following steps in sequence:

[0017] S1. When the sewing machine sews the first stitch, the capture drive source drives the holding member to move to the thread capture position. The thread through hole is located directly below the needle. The needle is threaded with a thread, and the thread has free sections distributed on one side of the needle.

[0018] S2. The sewing machine begins to sew the first stitch. The needle moves downward, passes through the thread through the hole, and moves down to the lowest point. Then, the needle moves upward, passes through the thread through the hole, and moves up to the highest point.

[0019] During the upward movement of the needle, the tip of the rotary hook catches the loop formed by the free segment of the thread and expands the loop; and when the needle moves upward from the thread through hole, the capture drive source drives the holding member to move to the initial position, and the free segment of the thread passes through the thread through hole.

[0020] S3. The sewing machine begins to sew the second stitch. The needle first moves down to the lowest point and then moves up to the highest point. During the upward movement of the needle, the tip of the rotary hook catches the loop generated by the free segment of the thread and expands the loop to form a stitch.

[0021] As described above, the thread-catching structure, sewing machine, and sewing control method of the present invention have the following beneficial effects:

[0022] This application, by setting a retainer with a thread through hole, can capture and hold the free segment of the top thread located on the needle side during the first stitch, and apply a holding force to the free segment of the top thread during the second stitch. This allows the free segment of the top thread to effectively generate a thread loop during the needle's upward movement while sewing the second stitch, thereby ensuring that the tip of the rotary hook can smoothly hook the thread loop, thus stabilizing the stitch and effectively guaranteeing sewing quality and stability. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the surface line capture structure in this application.

[0024] Figure 2 for Figure 1 A schematic diagram of the structure of the retainer.

[0025] Figures 3a to 3e This is a diagram illustrating the working process of the surface line capture structure in this application.

[0026] Component designation explanation

[0027] 10. Rotary Shuttle

[0028] 11. Spindle tip

[0029] 20 Retaining parts

[0030] 21 Through-hole

[0031] 30 Fixed tool

[0032] 40 Active Wire Cutting Blade

[0033] 41. First cutting edge

[0034] 50 needles

[0035] 60 ribs

[0036] 61 Free Section Detailed Implementation

[0037] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0038] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and objectives of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0039] This application provides a top thread capturing structure, a sewing machine equipped with the top thread capturing structure, and a sewing control method using the top thread capturing structure. The sewing machine is preferably a flatbed sewing machine, which includes a machine housing, a base plate, a needle plate fixed to the base plate, an upper shaft rotatably supported in the machine housing, a lower shaft rotatably supported in the base plate, a rotary hook fixed to the left end of the lower shaft, a needle bar mechanism driven by the upper shaft, and a needle. The rotary hook is located below the needle plate, and the needle bar mechanism drives the needle to reciprocate up and down.

[0040] like Figure 1 and Figure 2 As shown, the thread-catching structure involved in this application includes a rotatable rotary hook 10 in a sewing machine, a movable retainer 20, and a catching drive source for driving the retainer 20. The rotary hook 10 has a hook tip 11. The retainer 20 is distributed on the outer periphery of the rotary hook 10 and located below the needle 50 in the sewing machine. A through thread hole 21 is provided on the retainer 20. When the sewing machine sews the first stitch, the catching drive source drives the retainer 20 to move to the thread-catching position. The through thread hole 21 is located directly below the needle 50, allowing the needle 50 to pass through.

[0041] The sewing control method involved in this application includes the following steps in sequence:

[0042] S1. When the sewing machine sews the first stitch, the capture drive source drives the retaining element 20 to move to the thread capture position, such as... Figure 1 As shown, at this time, the through hole 21 is located directly below the needle 50, and the needle 50 is provided with a top thread 60, which has a free section 61 distributed on one side of the needle 50.

[0043] S2. The sewing machine begins to sew the first stitch. The needle moves downwards at position 50. Figure 3a As shown, the needle 50 passes downward through the thread through hole 21 and moves to the lowest point; then, as... Figure 3bAs shown, the needle 50 moves upward, passing through the thread through hole 21 and reaching its highest point; therefore, the needle 50 has a downward movement from its highest point to its lowest point, and an upward movement from its lowest point to its highest point. During the upward movement of the needle 50, as... Figure 3b As shown, the free segment 61 of the thread 60 relaxes, thereby generating a loop. The rotary hook 10 rotates counterclockwise, and the hook tip 11 of the rotary hook 10 hooks the loop generated by the free segment 61 of the thread 60 and expands the loop. As the needle 50 continues to move upward, after the needle 50 moves upward from the thread through hole 21, as... Figure 3c As shown, the capture drive source drives the retaining member 20 to move to the initial position, while the free segment 61 of the face thread 60 is hooked by the shuttle tip 11 and rotates counterclockwise with the rotary shuttle 10, ultimately causing the free segment 61 of the face thread 60 to pass through the thread through hole 21, as shown. Figure 3d As shown.

[0044] S3. The sewing machine begins sewing the second stitch. The needle 50 first moves down to its lowest point and then up to its highest point. The retaining element 20, located in its initial position, is not on the movement path of the needle 50 and will not interfere with the up-and-down movement of the needle 50. During the upward movement of the needle 50 while sewing the second stitch, if... Figure 3e As shown, since the free segment 61 of the face thread 60 passes through the thread through hole 21, there is friction between the two. That is, the thread through hole applies a holding force to the free segment 61 of the face thread 60, effectively holding the free segment 61 of the face thread 60. This allows the free segment 61 of the face thread 60 to effectively generate a thread loop, thereby ensuring that the tip 11 of the counterclockwise rotating shuttle 10 can smoothly hook the thread loop generated by the free segment 61 of the face thread 60 and expand the thread loop, stably and smoothly forming a stitch.

[0045] Therefore, by providing a retainer 20 with a thread through hole 21, this application can capture and retain the free segment 61 of the top thread 60 located on the side of the needle 50 in the thread through hole 21 when sewing the first stitch. When sewing the second stitch, a retaining force is also applied to the free segment 61 of the top thread 60, so that the free segment 61 of the top thread 60 can effectively and stably generate a thread loop during the upward movement of the needle 50 when sewing the second stitch. This ensures that the tip 11 of the rotary hook 10 can smoothly hook the thread loop, avoiding the inability to hook the top thread 60 at the beginning of sewing, thereby stabilizing the stitch and effectively ensuring sewing quality and stability.

[0046] Preferably, the retainer 20 moves by rotating about the central axis of the rotary hook 10. The through hole 21 is a circular hole or an oblong hole.

[0047] Furthermore, the retainer 20 can be a newly added moving part in the sewing machine, or it can be an existing moving part in the sewing machine. In this embodiment, the retainer 20 uses the existing moving thread cutter in the sewing machine, so the capture drive source is also the thread cutting drive source that drives the moving thread cutter to rotate, thereby reducing costs and simplifying the manufacturing process. It only requires machining an additional thread through hole 21 on the existing moving thread cutter. Based on the different forms of the thread cutting mechanism in the sewing machine, there are multiple embodiments of the retainer 20.

[0048] Retaining component 20, embodiment 1: The sewing machine is equipped with a single-action thread-cutting mechanism; such as... Figure 1 As shown, the single-action thread-cutting mechanism includes a fixed blade 30, a rotatable active thread-cutting blade 40, and a thread-cutting drive source connected to the active thread-cutting blade 40. The fixed blade 30 is fixed to the base plate of the sewing machine, the retaining member 20 is the active thread-cutting blade 40, and the capturing drive source is the thread-cutting drive source. The thread-cutting drive source can be a stepper motor, a cylinder, or an electromagnet. Figure 2 As shown, the active tangent 40 is provided with a first tangent cutting edge 41; along the retraction rotation direction of the active tangent 40, the first tangent cutting edge 41 and the through hole 21 are distributed successively on the rotation path of the active tangent 40, so the first tangent cutting edge 41 is closer to the fixed blade 30 than the through hole 21.

[0049] Embodiment 2: A sewing machine is equipped with a double-moving-blade thread-cutting mechanism. This double-moving-blade thread-cutting mechanism includes a rotatable active thread cutter 40 and an auxiliary moving thread cutter, and a thread-cutting drive source that is pulsatorically connected to both the active thread cutter 40 and the auxiliary moving thread cutter. The retaining member 20 is either the active thread cutter 40 or the auxiliary moving thread cutter, and the retaining drive source is the thread-cutting drive source. The thread-cutting drive source can be a stepper motor, a cylinder, or an electromagnet. The active tangent 40 is provided with a first tangent cutting edge 41, and the auxiliary active tangent 40 is provided with a second tangent cutting edge. When the retainer 20 is the active tangent 40, the first tangent cutting edge 41 and the through hole 21 are distributed sequentially on the rotation path of the active tangent 40 along the retraction rotation direction of the active tangent 40. Therefore, the first tangent cutting edge 41 is closer to the second tangent cutting edge than the through hole 21. When the retainer 20 is the auxiliary active tangent 40, the second tangent cutting edge and the through hole 21 are distributed sequentially on the rotation path of the auxiliary active tangent 40 along the retraction rotation direction of the auxiliary active tangent 40. Therefore, the second tangent cutting edge is closer to the first tangent cutting edge 41 than the through hole 21.

[0050] The following description uses the active wire cutter 40 in the single-action wire cutting mechanism of the retainer 20 as an example to illustrate the working principle of the wire capturing structure.

[0051] First, when the sewing machine begins sewing the first stitch, the thread-cutting drive source drives the active thread cutter 40 to rotate clockwise to the top thread capture position; or, when the sewing machine continues sewing the first stitch after thread cutting, the thread-cutting drive source drives the active thread cutter 40 to rotate to the top thread capture position. When the active thread cutter 40 is in the top thread capture position, as... Figure 1 As shown, the thread through-hole 21 is located directly below the needle 50, through which the top thread 60 passes. The top thread 60 has free segments 61 distributed on one side of the needle 50. The top thread capturing position and the thread cutting position of the active thread cutter 40 can be the same position or different positions. In this embodiment, the top thread capturing position of the active thread cutter 40 is located clockwise from the thread cutting position; therefore, when cutting the thread, the thread cutting drive source first drives the active thread cutter 40 to rotate clockwise to the thread cutting position to cut the top thread 60; then, when starting the next sewing, the thread cutting drive source continues to drive the active thread cutter 40 to rotate clockwise to the top thread capturing position.

[0052] Second, begin sewing the first stitch. The needle 50 first moves down to the lowest point, then moves up to the highest point. The active thread cutter 40 remains in the top thread capture position. The needle 50 then passes downwards through the thread guide hole 21 of the active thread cutter 40 and moves down to the lowest point. Figure 3a As shown; then, the needle 50 passes upward through the thread through hole 21 of the active thread cutter 40 and moves to the highest point, as shown. Figure 3b As shown. During the upward movement of the needle 50, the rotary hook 10 rotates counterclockwise, and the hook tip 11 of the rotary hook 10 hooks the loop of thread formed by the free segment 61 of the thread 60 and expands the loop; when the needle 50 moves upward from the thread through hole 21, as... Figure 3c As shown, the thread-cutting drive source drives the active thread cutter 40 to rotate counterclockwise to the initial position, and the active thread cutter 40 resets. The first stitch will not form a complete stitch; the free segment 61 of the top thread 60 finally passes through the thread through hole 21 of the active thread cutter 40, as shown. Figure 3d As shown.

[0053] Third, begin sewing the second stitch. The needle 50 first moves down to its lowest point, then moves up to its highest point. The active thread cutter 40 remains in its initial position throughout. During the upward movement of the needle 50 while sewing the second stitch, if... Figure 3eAs shown, since the free segment 61 of the top thread 60 passes through the thread through hole 21, there is friction between them. That is, the thread through hole applies a holding force to the free segment 61 of the top thread 60, effectively holding the free segment 61 of the top thread 60. This allows the free segment 61 of the top thread 60 to effectively form a loop, thus ensuring that the tip 11 of the counterclockwise rotating rotary hook 10 can smoothly hook the loop formed by the free segment 61 of the top thread 60 and expand the loop, forming a stable and smooth stitch. During the second stitch, under the combined action of the tip 11 of the rotary hook 10 expanding the loop and the fabric being moved forward, the free segment 61 of the top thread 60 will come out of the thread through hole 21 of the active thread cutter 40. The resulting bird's nest is almost the same size as during normal sewing, without affecting the sewing quality.

[0054] Fourth, continue sewing until it is finished, starting from the second stitch, to effectively form a stitch on the fabric.

[0055] Fifth, after sewing is completed, the thread is automatically cut. The thread cutting drive source drives the active thread cutter 40 to rotate clockwise to the thread cutting position. After the thread is cut, the thread cutting drive source drives the active thread cutter 40 to rotate clockwise to the top thread capture position, and enters the next sewing, continuing to capture the free segment 61 of the top thread 60.

[0056] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0057] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A sewing control method using a thread catching structure including a rotatable rotating hook (10) in a sewing machine, the rotating hook (10) having a hook tip (11), characterized by: The thread catching structure further comprises movable holders (20) distributed on the outer circumferential side of the rotating hook (10) and located below the needle (50) in the sewing machine, and overline through holes (21) are formed in the holders (20); The sewing control method comprises the following steps in sequence: S1. When the sewing machine sews the first needle, the catching driving source drives the holders (20) to rotate clockwise to a thread catching position, the overline through holes (21) are located directly below the needle (50), the needle (50) is provided with the thread (60), and the thread (60) has a free section (61) distributed on one side of the needle (50); S2. The sewing machine starts to sew the first needle, the needle (50) moves downward, the needle (50) passes through the overline through holes (21) downward and moves downward to the lowest point, then the needle (50) moves upward, the needle (50) passes through the overline through holes (21) upward and moves upward to the highest point; The rotating hook (10) rotates counterclockwise, in the upward movement process of the needle (50), the hook tip (11) of the rotating hook (10) hooks the thread loop generated by the free section (61) of the thread (60) and expands the thread loop, and when the needle (50) moves out of the overline through holes (21) upward, the catching driving source drives the holders (20) to rotate counterclockwise to the initial position, and the free section (61) of the thread (60) is provided in the overline through holes (21); S3. The sewing machine starts to sew the second needle, the needle (50) moves downward to the lowest point and then moves upward to the highest point, in the upward movement process of the needle (50), the free section (61) of the thread (60) is provided in the overline through holes (21) and friction exists between them, so that the overline through holes (21) hold the free section (61) of the thread (60), thereby the hook tip (11) of the rotating hook (10) hooks the thread loop generated by the free section (61) of the thread (60) and expands the thread loop, and a stitch is formed; In the process of sewing the second needle, under the combined action of the expansion of the thread loop by the hook tip (11) of the rotating hook (10) and the forward movement of the fabric, the free section (61) of the thread (60) is separated from the overline through holes (21) of the holders (20).

2. The sewing control method according to claim 1, characterized by: The holders (20) rotate around the central axis of the rotating hook (10).

3. The sewing control method according to claim 1, characterized by: The overline through holes (21) are circular holes or waist-shaped holes.

4. The sewing control method according to claim 1, characterized by: The sewing machine is provided with a single-action knife thread trimming mechanism, the single-action knife thread trimming mechanism comprises a fixed fixed knife (30), a movable driving thread cutting knife (40), and a thread trimming driving source in transmission connection with the driving thread cutting knife (40), the holders (20) are the driving thread cutting knife (40), and the catching driving source is the thread trimming driving source.

5. The sewing control method according to claim 4, characterized by: The active thread cutting knife (40) is provided with a first thread cutting edge (41); along the retreat direction of the active thread cutting knife (40), the first thread cutting edge (41) and the thread passing hole (21) are distributed in sequence in the rotation path of the active thread cutting knife (40).

6. The sewing control method according to claim 1, characterized by: The sewing machine is provided with a double-acting knife thread trimming mechanism, which comprises an active thread cutting knife (40) and an auxiliary active thread cutting knife, which can rotate, and a thread trimming driving source in driving connection with the active thread cutting knife (40) and the auxiliary active thread cutting knife; the holding member (20) is the active thread cutting knife (40) or the auxiliary active thread cutting knife, and the capture driving source is the thread trimming driving source.

7. The sewing control method according to claim 6, characterized by: The active thread cutting knife (40) is provided with a first thread cutting edge (41), and the auxiliary active thread cutting knife is provided with a second thread cutting edge; When the holding member (20) is the active thread cutting knife (40), along the retreat direction of the active thread cutting knife (40), the first thread cutting edge (41) and the thread passing hole (21) are distributed in sequence in the rotation path of the active thread cutting knife (40); When the holding member (20) is the auxiliary active thread cutting knife, along the retreat direction of the auxiliary active thread cutting knife, the second thread cutting edge and the thread passing hole (21) are distributed in sequence in the rotation path of the auxiliary active thread cutting knife.

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