Anti-thread-trapping shuttle

Abstract

The application provides a thread anti-pinch rotary hook, which comprises an outer hook, a triangular pyramid is arranged on the side wall of the outer hook, the tip of the triangular pyramid forms a hook tip of the outer hook, an inner wall of the outer hook is provided with a guide groove communicated with the triangular pyramid, a thread guide arc is formed from the hook tip of the outer hook to one side of the guide groove, a guide groove upper opening sharp corner and a guide groove lower opening sharp corner are arranged at the position where the guide groove end wall and the thread guide arc are connected, and the guide groove upper opening sharp corner and the guide groove lower opening sharp corner are sequentially arranged along the direction of the guide groove from the hook tip of the outer hook; the application further comprises a thread avoiding surface, the thread avoiding surface is arranged on the thread guide arc of the triangular pyramid and cuts off the guide groove lower opening sharp corner, when the hook tip hooks the surface thread to form a thread loop which rapidly expands along the thread guide arc, the thread loop rapidly passes through the guide groove lower opening sharp corner, the obstruction of the guide groove lower opening sharp corner to the movement of the thread loop is reduced, the problem that the thread loop stays in the middle of the guide groove is solved, the thread separating hook on the inner hook pushes the thread loop into the guide groove is avoided, and the risk that the thread separating hook and the inner wall of the guide groove clamp the thread loop is reduced.

Description

Technical Field

[0001] This application relates to the field of sewing machine accessories, and more particularly to an anti-thread-clamping rotary hook. Background Technology

[0002] The rotary shuttle is the core component of a sewing machine that forms a double-lock stitch. It mainly includes an outer shuttle and an inner shuttle. The outer shuttle is fitted outside the inner shuttle and rotates at high speed around the axis of the inner shuttle.

[0003] The working cycle of the rotary hook is divided into three stages: hooking the thread, separating the thread, and unhooking the thread. The rotary hook rotates twice for every one revolution of the main shaft, and the specific angle range corresponds to the hooking of the thread loop and the unhooking of the needle.

[0004] Specifically, such as Figure 2 As shown, a triangular pyramid 11 is provided on the side wall of the outer shuttle 1, wherein the tip of the triangular pyramid 11 forms the outer shuttle tip 12. A guide groove 13 is provided on the side wall of the outer shuttle 1. The thread divider hook 21 on the inner shuttle 2 is screwed into the guide groove 13 and slidably connected to the inner wall of the guide groove 13. The triangular pyramid 11 extends from the outer shuttle tip 12 to the guide groove 13 with a guide arc 14. The end wall of the guide groove 13 and the guide arc 14 form sharp angles at the junction, which are successively divided into the upper guide groove tip 131 and the lower guide groove tip 132. The outer shuttle tip 12 After hooking the thread on the needle, a loop is formed. The loop moves from the side of the outer shuttle tip 12 of the triangular cone 11 to the side of the guide groove 13 and gradually expands so that it can be hooked by the thread divider hook 21 on the inner shuttle 2, thereby transferring the loop to the inner shuttle 2. During the movement, the loop is prone to touching the lower opening sharp corner 132 of the guide groove 13, which affects the loop from passing the lower opening sharp corner 132. At this time, the thread divider hook 21 pushes the loop into the guide groove 13, which can easily cause the loop to get stuck at this position, thereby increasing the risk of thread breakage.

[0005] Therefore, how to design a rotary hook that solves the problem of the sharp corner at the bottom of the guide groove affecting the movement of the wire ring and causing the wire ring to be clamped has become a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0006] This application provides an anti-pinch rotary hook to at least solve the above-mentioned technical problems existing in the prior art.

[0007] A non-pinchable rotary hook is provided, including an outer hook, a triangular cone on the side wall of the outer hook, the tip of the triangular cone forming the outer hook tip, a guide groove communicating with the triangular cone on the inner wall of the outer hook, a lead wire arc forming from the outer hook tip to one side of the guide groove, and an upper opening sharp corner and a lower opening sharp corner of the guide groove at the junction of the end wall of the guide groove and the lead wire arc, the upper opening sharp corner and the lower opening sharp corner of the guide groove being arranged sequentially along the direction from the outer hook tip to the guide groove; it also includes a wire-avoiding surface, which is set on the lead wire arc of the triangular cone and cuts off the lower opening sharp corner of the guide groove.

[0008] In one embodiment, a thread-hanging surface is also included, which is disposed on the lead wire arc between the tip of the outer shuttle and the upper corner of the guide groove.

[0009] In one embodiment, the hanging surface is triangular in shape, with one of its sharp corners coinciding with the lead wire arc, while the other two sharp corners of the hanging surface do not extend to the guide groove.

[0010] In one embodiment, the device also includes an inner shuttle, the outer wall of which is provided with a thread hook extending radially outward along the inner shuttle. The end wall of the thread hook forms a first angle with the outer wall of the inner shuttle, and the first angle is used to hook a thread loop.

[0011] In one possible implementation, the first included angle is an acute angle.

[0012] Compared with the prior art, the anti-pinch rotary hook of this application has the following beneficial effects: This application provides a thread-avoiding surface at the pointed corner of the guide groove at the bottom of the outer shuttle guide groove, thereby cutting off the pointed corner of the guide groove. When the shuttle tip hooks the thread to form a thread loop and rapidly expands along the lead wire arc, it quickly passes over the pointed corner of the guide groove, reducing the obstruction of the pointed corner of the guide groove to the movement of the thread loop and solving the problem of the thread loop staying in the middle of the guide groove. This avoids the thread splitting hook on the inner shuttle pushing the thread loop into the guide groove, thereby reducing the risk of the thread splitting hook and the inner wall of the guide groove clamping the thread loop. Compared to the existing technology where the sharp corner of the guide groove at the bottom can easily obstruct the thread loop, in this application, the setting of the thread-avoiding surface allows the thread loop to smoothly pass around the bottom of the inner shuttle, thereby detaching the thread loop from the inner shuttle, making it easier for the top thread to pass around the bottom thread to form a thread lock and form a stitch on the sewn fabric.

[0013] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0014] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings. Several embodiments of this application are illustrated in the drawings by way of example and not limitation, in which: In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0015] Figure 1 A schematic diagram of the overall structure of the prior art is shown; Figure 2 A schematic diagram of the prior art is shown; Figure 3 A schematic diagram of the structure of the outer shuttle of this application is shown; Figure 4A partial cross-sectional view of the rotary hook of this application is shown; Figure 5 A cross-sectional view of the triangular pyramid of this application is shown.

[0016] Explanation of the labels in the diagram: 1. Outer shuttle; 10. Inner cavity; 11. Triangular pyramid; 12. Outer shuttle tip; 13. Guide groove; 131. Upper opening sharp angle of guide groove; 132. Lower opening sharp angle of guide groove; 14. Lead wire arc; 2. Inner shuttle; 21. Dividing line hook; 3. Avoid the line surface; 4. Hanging line surface; 5. First included angle. Detailed Implementation

[0017] To make the objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0018] The rotary shuttle includes an outer shuttle 1 and an inner shuttle 2. The outer shuttle 1 is fitted on the outside of the inner shuttle 2, and the outer shuttle 1 rotates at high speed around the axis of the inner shuttle 2.

[0019] The outer shuttle 1 is provided with an inner cavity 10 with an opening on one side, wherein the inner shuttle 2 is installed in the inner cavity 10 of the outer shuttle 1. It is worth noting that the outer shuttle 1 and the inner shuttle 2 are coaxially arranged.

[0020] The outer shuttle 1 has an opening on its side wall that communicates with one side of the inner cavity 10. A triangular pyramid 11 is formed at the opening on the side wall of the outer shuttle 1. The tip of the triangular pyramid 11 is provided with an outer shuttle tip 12. During operation, the outer shuttle tip 12 slides over the side of the needle and hooks the thread on the needle to form a loop. As the outer shuttle 1 continues to rotate, the triangular pyramid 11 continues to expand the loop, thereby expanding the loop.

[0021] Furthermore, the outer shuttle 1 has a guide groove 13 distributed along the circumference of the inner cavity 10 on its peripheral wall, and the inner shuttle 2 has a dividing hook 21 extending radially outward along its outer wall. After the inner shuttle 2 is installed in the inner cavity of the outer shuttle 1, the dividing hook 21 extends into the guide groove 13.

[0022] When the tip 12 of the outer shuttle hooks the top thread to form a loop, the loop is enlarged by the triangular cone 11 and hooked by the thread divider hook 21, thereby transferring the loop to the thread divider hook 21 of the inner shuttle 2. The outer shuttle 1 continues to rotate. At this time, one side thread of the loop separates from the outer shuttle 1 and goes around the bottom thread in the inner shuttle 2. The other side thread of the loop slides from the bottom of the inner shuttle 2 and loops the bottom thread in the middle. Then the loop is tightened to form a stitch on the fabric.

[0023] In order for the triangular pyramid 11 to enlarge the loop and fit it onto the dividing hook 21, at this time, as Figure 2 As shown, a lead wire arc 14 is provided on the triangular pyramid 11, wherein the wire loop is gradually stretched open as the lead wire arc 14 extends to one side of the guide groove 13.

[0024] Specifically, such as Figure 2 As shown, at the junction of the end wall of the guide groove 13 and the lead wire arc 14, an upper opening sharp corner 131 and a lower opening sharp corner 132 of the guide groove are formed. The upper opening sharp corner 131 and the lower opening sharp corner 132 of the guide groove are sequentially arranged on the lead wire arc 14 along the direction from the outer shuttle tip 12 to the guide groove 13.

[0025] During operation, in order for the thread ring to be better hooked by the splitting hook 21 and transferred to the inner shuttle 2, the thread ring needs to quickly cross the lower corner 132 of the guide groove. In practice, the thread ring is easily obstructed by the lower corner 132 of the guide groove. At this time, the thread ring will stop in the middle of the guide groove 13. When the splitting hook 21 contacts the thread ring, the splitting hook 21 and the inner wall of the guide groove 13 will clamp the thread ring, which can easily lead to thread breakage.

[0026] To address the obstruction of the wire loop by the sharp corner 132 at the bottom of the guide groove, in this embodiment, as follows: Figure 3 As shown, the lead wire arc 14 is provided with a wire-avoiding surface 3 for cutting off the sharp corner 132 at the bottom of the guide groove.

[0027] By setting the wire-avoiding surface 3, when the wire ring moves along the lead wire arc 14, it can quickly pass the lower opening sharp corner 132 of the guide groove, reducing the obstruction of the lower opening sharp corner 132 of the guide groove on the movement of the wire ring, so that the wire-separating hook 21 can hook the wire ring and realize the transfer of the wire ring from the outer shuttle 1 to the inner shuttle 2.

[0028] After the outer shuttle tip 12 hooks the face thread to form a loop, the loop moves along the guide arc 14, thereby gradually expanding the loop so that the split hook 21 can hook the loop. The guide arc 14 is on the triangular pyramid 11, and the guide arc 14 is one of the edges of the triangular pyramid 11. At this time, the friction between the loop and the guide arc 14 is relatively large, which results in a slow movement speed of the loop and is not conducive to the rapid sliding of the loop.

[0029] Therefore, in this embodiment, as Figure 3 and Figure 5As shown, in order to reduce the friction between the wire loop and the lead wire arc 14, a wire hanging surface 4 is also included. The wire hanging surface 4 is disposed between the upper tip corner 131 of the guide groove and the outer shuttle tip 12. The placement of the wire hanging surface 4 can increase the included angle formed after the wire loop and the lead wire arc 14 come into contact, reduce the shearing force of the lead wire arc 14 on the wire loop, thereby reducing the friction between the wire loop and the lead wire arc 14, so that the wire loop can slide quickly on the triangular pyramid 11.

[0030] Furthermore, such as Figure 3 As shown, the hanging surface 4 is triangular in shape, including three sharp corners and three sides, all of which are arcs. The sharp corner of the hanging surface 4 near the outer shuttle tip 12 coincides with the lead wire arc 14. At this time, the other two sharp corners of the hanging surface 4 do not contact the guide groove 13, thus ensuring the integrity of the upper opening sharp corner 131 of the guide groove.

[0031] Compared to the lead wire arc 14 in the prior art, the setting of the hanging surface 4 can quickly expand the wire ring and increase its diameter before the wire hook 21 enters the guide groove 13, so that the wire hook 21 can hook the wire ring.

[0032] It is worth noting that before the wire ring enters the guide groove 13, the larger the diameter of the wire ring, the lower the wire ring is on the side closer to the inner shuttle 2, and the closer it is to the outer wall of the inner shuttle 2, so that the wire ring can be hooked by the wire ring by the wire hook 21.

[0033] To improve the hooking effect of the split hook 21 on the loop, such as Figure 4 As shown, a first included angle 5 is formed between the end wall of the dividing hook 21 and the outer wall of the inner shuttle 2. The first included angle 5 is an acute angle. When the dividing hook 21 and the outer wall of the inner shuttle 2 hook each other at the first included angle 5, the risk of the wire loop coming off the dividing hook 21 is reduced.

[0034] In this embodiment, the hanging surface 4 also reduces the risk of the rotary hook skipping.

[0035] Here is an explanation of the jumper thread: After the outer shuttle tip 12 hooks the opposite thread to form a loop, the loop will expand along the direction of the lead wire arc 14. When the diameter of the loop is small, the loop is far from the outer wall of the inner shuttle 2, and there is a risk that the splitting hook 21 will not hook the loop, thus causing the jumper thread problem.

[0036] In this embodiment, after the thread loop is rapidly expanded by the hanging surface 4, the diameter of the thread loop increases rapidly, and the thread loop is closer to the outer wall of the inner shuttle 2. The root of the first included angle 5 on the dividing hook 21 will hook the thread loop, further reducing the risk of the thread loop detaching from the first included angle 5 on the dividing hook 21.

[0037] In this embodiment, the thread-avoiding surface 3 is set on the thread-leading arc 14 at the lower corner 132 of the guide groove. After the lower corner 132 of the guide groove is cut off, the obstruction of the lower corner 132 of the guide groove to the thread loop is solved, and the thread loop can smoothly pass around the bottom of the inner shuttle 2, so that the thread loop can be separated from the inner shuttle 2, so that the top thread and the bottom thread can form a thread lock, thereby forming a stitch on the sewing material.

[0038] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this application can be achieved, and this is not limited herein.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0040] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A type of anti-pinch shuttle, comprising an outer shuttle (1), a triangular cone (11) on the side wall of the outer shuttle (1), the tip of the triangular cone (11) forming an outer shuttle tip (12), a guide groove (13) communicating with the triangular cone (11) on the inner wall of the outer shuttle (1), a lead wire arc (14) forming from the outer shuttle tip (12) to one side of the guide groove (13), and an upper guide groove tip (131) and a lower guide groove tip (132) at the junction of the end wall of the guide groove (13) and the lead wire arc (14), the upper guide groove tip (131) and the lower guide groove tip (132) being arranged sequentially along the direction from the outer shuttle tip (12) to the guide groove (13); characterized in that, It also includes a wire avoidance surface (3), which is set on the lead arc (14) of the triangular cone (11) and cuts off the sharp corner (132) at the bottom of the guide groove.

2. The anti-pinch rotary hook according to claim 1, characterized in that, It also includes a hanging surface (4), which is set on the lead wire arc (14) between the outer shuttle tip (12) and the upper opening tip (131) of the guide groove.

3. The anti-pinch rotary hook according to claim 2, characterized in that, The hanging surface (4) is triangular in shape. One of the sharp corners of the hanging surface (4) coincides with the lead wire arc (14), while the other two sharp corners of the hanging surface (4) do not extend to the guide groove (13).

4. A wire-clamping rotary hook according to claim 2 or 3, characterized in that, It also includes an inner shuttle (2), on the outer wall of which is provided a line hook (21) extending radially outward along the inner shuttle (2). The end wall of the line hook (21) forms a first angle (5) with the outer wall of the inner shuttle (2), and the first angle (5) is used to hook the line loop.

5. A rotary hook for preventing thread pinching according to claim 4, characterized in that, The first included angle (5) is an acute angle.

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