Thread clamping mechanism for a sewing machine

Abstract

The utility model provides a thread clamping mechanism of sewing machine belongs to sewing machine technical field. It solved the problem that the thread head is easy to be taken out when the existing sewing machine is sewing. The thread clamping mechanism of sewing machine, sewing machine includes bottom plate, needle, shuttle and the dynamic cutter of arc shape, the thread clamping mechanism of sewing machine includes the pressing line piece of flaky fixed in bottom plate downside, the front side of pressing line piece has the protruding pressing line part, the dynamic cutter is passed through and is set up and has the long strip -shaped thread -catching groove, and the one end of thread -catching groove is located below above needle, when the dynamic cutter swings around the axis of shuttle to the pressing line piece direction, the pressing line part can be moved to the upper side of dynamic cutter from the upper side of the one end of thread -catching groove to the upper side of the other end after another, and the upper side of dynamic cutter at the other end of thread -catching groove is attached. The thread clamping mechanism of sewing machine has the advantage that the sewing quality is good.

Description

Technical Field

[0001] This utility model belongs to the field of sewing machine technology and relates to a sewing machine thread clamping mechanism. Background Technology

[0002] A sewing machine is a machine that uses one or more sewing threads to form one or more stitches on fabric, so that one or more layers of fabric are interwoven or sewn together. It is widely used in the garment industry.

[0003] When a sewing machine is working, the needle first pulls the top thread through the fabric from top to bottom. Then, as the needle rises, the top thread forms a tiny loop under the fabric. Next, the rotating hook tip, located below the needle plate, passes through this small loop, enlarging it and causing it to wrap around the bobbin in a "jump rope" motion, lifting the bobbin thread to form a lockstitch.

[0004] However, in existing sewing machines, the top thread is held in the fabric solely by the friction between it and the fabric when sewing the first stitch. When the friction is low or the top thread is short, the remaining top thread on the fabric is easily carried away by the subsequent needle pull, leading to skipped stitches, missed stitches, and other issues that reduce sewing quality and efficiency. Utility Model Content

[0005] The purpose of this invention is to address the aforementioned problems in the existing technology by proposing a sewing machine thread clamping mechanism that solves the problem that the thread end is easily pulled out during sewing in existing sewing machines.

[0006] The objective of this utility model can be achieved through the following technical solutions: A thread clamping mechanism for a sewing machine, the sewing machine including a base plate, a needle vertically disposed above the base plate, a rotary hook disposed below the base plate, and an arc-shaped movable blade, the movable blade being disposed close to the rotary hook and capable of circumferentially swinging around the axis of the rotary hook, characterized in that the thread clamping mechanism of the sewing machine includes a sheet-shaped pressure plate fixed to the lower side of the base plate, the front side of the pressure plate having a protruding pressure portion, the movable blade having a long strip-shaped thread-grabbing groove penetrating through it, and one end of the thread-grabbing groove being located below the needle, when the movable blade swings around the axis of the rotary hook toward the pressure plate, the pressure portion can move relative to the movable blade from above one end of the thread-grabbing groove to above the other end and then abut against the upper side of the movable blade at the other end of the thread-grabbing groove.

[0007] When not in use, the thread holding mechanism of this sewing machine has the needle positioned above the base plate, the pressure plate on one side of the rotary hook, and the moving blade on the other side of the rotary hook, with one end of the thread-holding groove on the moving blade directly below the needle. When sewing begins, the needle pulls the thread through the needle eye downwards and through one end of the thread-holding groove on the moving blade. As the needle rises, the rotary hook causes the thread end to descend and pass through the thread-holding groove. Before the needle performs its next stitch, the existing thread-cutting motor drives the moving blade to swing towards the pressure plate. Because the pressure plate aligns with the thread-holding groove, it blocks the thread passing downwards through the groove. During the swinging motion, the pressure plate pushes the thread towards the other end of the thread-holding groove until the pressure plate abuts against the upper side of the moving blade at the other end of the groove, clamping the thread between the pressure plate and the moving blade, thus securing the thread. After that, the moving blade remains stationary, and the needle can continue sewing. After sewing several stitches, the moving blade can continue to swing under the drive of the thread-cutting motor until the pressing part disengages from the moving blade, releasing the clamping of the opposite thread.

[0008] In the thread clamping mechanism of this sewing machine, by setting up the pressure plate and cooperating with the thread gripping groove opened on the existing moving knife, the thread after the needle sews the first stitch can be clamped, avoiding situations such as skipped stitches and missed stitches, thus ensuring sewing quality and efficiency.

[0009] In the thread clamping mechanism of the sewing machine described above, the groove wall at the other end of the thread gripping groove is arc-shaped. The arc-shaped groove wall prevents the thread gripping groove itself from clamping the thread, ensuring smooth thread release when needed.

[0010] In the thread clamping mechanism of the sewing machine described above, the width of the thread gripping groove gradually decreases from one end to the other. The wider groove at one end facilitates the passage of the needle and thread, while the gradually narrowing groove guides the movement of the thread, ensuring that the pressing part can accurately clamp the thread in conjunction with the moving blade.

[0011] In the thread clamping mechanism of the sewing machine described above, a cutting notch is provided on the side of the moving blade away from the pressure plate. The cutting notch is located on the other side, so it does not affect the clamping of the thread, and the thread can be cut when the moving blade moves away from the pressure plate.

[0012] In the thread clamping mechanism of the sewing machine described above, there is a gap between the groove wall at one end of the thread gripping groove and the side of the moving blade facing the pressure plate. One end of the thread gripping groove does not penetrate the moving blade, which ensures the strength of the moving blade itself and effectively prevents the thread from slipping out of the thread gripping groove.

[0013] In another scenario, in the thread holding mechanism of the sewing machine described above, one end of the thread gripping groove extends to the side of the moving blade facing the pressure plate. The open end of the thread gripping groove provides more space for the needle and thread to pass through.

[0014] In the thread clamping mechanism of the sewing machine described above, the groove wall at the other end of the thread gripping groove and the upper side of the moving blade form a rounded transition. This rounded transition at the corners prevents cutting the thread during clamping, ensuring the stability of the thread clamping.

[0015] Compared with existing technologies, the thread clamping mechanism of this sewing machine, through the setting of the pressure plate and the additional thread-grabbing groove on the existing moving knife, can clamp the thread after the needle has made the first stitch, avoiding skipped stitches and missed stitches, thus ensuring sewing quality and efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the thread clamping mechanism of this sewing machine.

[0017] Figure 2 This is a schematic diagram of the moving blade in the thread clamping mechanism of this sewing machine.

[0018] Figure 3 This is a schematic diagram of the initial position of the thread clamping mechanism of this sewing machine during use.

[0019] Figure 4 This is a schematic diagram of the sewing machine's thread clamping mechanism after the needle descends for the first time during use.

[0020] Figure 5 This is a schematic diagram of the needle lifting mechanism when the thread clamping mechanism of this sewing machine is in use.

[0021] Figure 6 This is a schematic diagram of the structure of the thread clamping mechanism of this sewing machine, showing the movement of the moving blade towards the pressure plate.

[0022] Figure 7 This is a schematic diagram of the sewing machine's thread clamping mechanism for holding the thread.

[0023] Figure 8 This is a schematic diagram of the sewing machine's thread clamping mechanism, which allows the needle to continue sewing during operation.

[0024] Figure 9 This is a schematic diagram of the sewing machine's thread clamping mechanism when it releases the thread.

[0025] In the diagram, 1 is the base plate; 2 is the needle; 3 is the rotary hook; 4 is the moving knife; 4a is the thread-grabbing groove; 4b is the thread-cutting edge; 5 is the thread-pressing plate; and 5a is the thread-pressing part. Detailed Implementation

[0026] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0027] For ease of description, the following descriptions are based on the orientation shown in the attached diagram.

[0028] like Figure 1 As shown, the sewing machine includes a plate-shaped and horizontally arranged base plate 1, a needle 2 vertically arranged above the base plate 1, a rotary hook 3 rotatably arranged below the base plate 1, and an arc-shaped moving blade 4. The moving blade 4 is arranged coaxially with the rotary hook 3, the moving blade 4 is close to the rotary hook 3, and the moving blade 4 can swing back and forth around the axis of the rotary hook 3 under the drive of the thread cutting motor.

[0029] The sewing machine's thread clamping mechanism includes a long, flat pressing plate 5 fixed to the lower side of the base plate 1. The left end of the pressing plate 5 is fixed to the base plate 1, and the front side of the right end of the pressing plate 5 has a forward-protruding, flat pressing part 5a. The lower side of the pressing part 5a can abut against the upper side of the moving blade 4.

[0030] like Figure 2 As shown, a recessed tangent 4b is provided on the right side of the front part of the moving blade 4. A long, narrow wire-grabbing groove 4a is also provided through the moving blade 4. The wire-grabbing groove 4a is arc-shaped, with its left end located to the left of the tangent 4b and its right end extending to the rear of the tangent 4b. The width of the wire-grabbing groove 4a gradually decreases from one end to the other, with the width of the left end of the wire-grabbing groove 4a in the front-back direction being greater than the width of the right end of the wire-grabbing groove 4a in the front-back direction. In this embodiment, there is a gap between the groove wall at the left end of the wire-grabbing groove 4a and the left side surface of the moving blade 4. Of course, if needed, the left end of the wire-grabbing groove 4a can also extend to the left side surface of the moving blade 4, i.e., penetrating the left side of the cutting blade. The groove wall at the right end of the wire-grabbing groove 4a is arc-shaped, and the upper part of the groove wall at the right end of the wire-grabbing groove 4a and the upper side surface of the moving blade 4 form an arc transition.

[0031] like Figure 3 As shown, when the sewing machine's thread clamping mechanism is not in use, the needle 2 is located above the base plate 1, the thread passes through the needle hole on the lower side of the needle 2, the pressure plate 5 is located on the left side of the rotary hook 3, and the moving knife 4 is mostly located on the right side of the rotary hook 3. The left end of the thread gripping groove 4a on the moving knife 4 is located directly below the needle 2, and there is a gap between the upper left end of the moving knife 4 and the pressure plate 5.

[0032] like Figure 4 As shown, when the sewing work begins, the needle 2 drives the thread downward and passes through the left end of the thread-grabbing groove 4a on the moving knife 4.

[0033] like Figure 5 As shown, the needle 2 is raised, and the rotary hook 3 makes the thread end of the top thread go down and pass through the thread gripping groove 4a, that is, the thread end is located below the thread gripping groove 4a.

[0034] like Figure 6As shown, before the needle 2 performs the next sewing, the upper left end of the moving blade 4 is driven by the existing thread-cutting motor of the sewing machine to swing towards the pressure plate 5. Since the lower side of the pressure plate 5a abuts against the upper side of the moving blade 4, and the position of the pressure plate 5a corresponds to the position of the thread-grabbing groove 4a, during the swing of the moving blade 4, the pressure plate 5a will block the top thread passing through the thread-grabbing groove 4a from top to bottom, and cause the top thread to move relative to the moving blade 4 towards the right end of the thread-grabbing groove 4a.

[0035] like Figure 7 As shown, the moving blade 4 moves relative to the pressing part 5a until it abuts against the upper side of the moving blade 4 at the right end of the gripping groove 4a, clamping the face thread between the pressing part 5a and the moving blade 4, thereby clamping and fixing the face thread.

[0036] like Figure 8 As shown, the moving blade 4 remains stationary, while the needle 2 continues to move up and down to sew the fabric.

[0037] like Figure 9 As shown, after sewing several stitches, the moving blade 4 can continue to swing in the previous direction under the drive of the thread-cutting motor until the pressing part 5a disengages from the right end of the moving blade 4, thus releasing the clamping of the opposite thread. After that, the fabric is fed forward normally, and the normal sewing process begins.

[0038] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A thread clamping mechanism for a sewing machine, the sewing machine comprising a base plate (1), a needle (2) vertically disposed above the base plate (1), a rotary hook (3) disposed below the base plate (1), and a circularly shaped moving blade (4), wherein the moving blade (4) is disposed close to the rotary hook (3) and the moving blade (4) is circumferentially oscillating around the axis of the rotary hook (3), characterized in that, The sewing machine's thread clamping mechanism includes a sheet-shaped pressing plate (5) fixed to the lower side of the base plate (1). The front side of the pressing plate (5) has a protruding pressing part (5a). The moving blade (4) has a long strip-shaped thread-grabbing groove (4a) through it, and one end of the thread-grabbing groove (4a) is located below the aforementioned needle (2). When the moving blade (4) swings around the axis of the rotary hook (3) toward the pressing plate (5), the pressing part (5a) can move relative to the moving blade (4) from above one end of the thread-grabbing groove (4a) to above the other end and then abut against the upper side of the moving blade (4) at the other end of the thread-grabbing groove (4a).

2. The thread clamping mechanism for a sewing machine according to claim 1, characterized in that, The groove wall at the other end of the wire-grabbing groove (4a) is arc-shaped.

3. A thread clamping mechanism for a sewing machine according to claim 1 or 2, characterized in that, The width of the wire gripping groove (4a) gradually decreases from one end to the other.

4. A thread clamping mechanism for a sewing machine according to claim 1 or 2, characterized in that, The moving blade (4) has a cutting notch (4b) on the side away from the pressure plate (5).

5. A thread clamping mechanism for a sewing machine according to claim 1 or 2, characterized in that, There is a gap between the groove wall at one end of the wire gripping groove (4a) and the side of the moving knife (4) facing the wire pressing piece (5).

6. A thread clamping mechanism for a sewing machine according to claim 1 or 2, characterized in that, One end of the wire gripping groove (4a) is opened to the side of the moving knife (4) facing the wire pressing piece (5).

7. A thread clamping mechanism for a sewing machine according to claim 1 or 2, characterized in that, The groove wall at the other end of the wire-grabbing groove (4a) and the upper side of the moving knife (4) are connected by an arc transition.

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