Inner shuttle structure of sewing machine

Abstract

The utility model provides an inner shuttle structure of a sewing machine, and belongs to the technical field of sewing machine accessories. The problem that in the prior art, thread throwing is prone to being generated in the sewing process is solved. The inner shuttle structure of the sewing machine comprises a cylindrical inner shuttle body, the outer edge of the inner shuttle body is provided with a needle falling groove and an anti-injury protruding edge arranged in the radial direction of the inner shuttle body in a protruding mode, the inner edge of the inner shuttle body is provided with a protruding block, and the protruding block and the anti-injury protruding edge are located on the same side of the inner shuttle body. A blocking face and a guiding face which intersect with the inner edge face of the inner shuttle body are arranged on the sides, close to and away from the needle falling groove, of the protruding block respectively, the guiding face and the blocking face are in smooth transition connection, and the included angle between the guiding face and the inner edge face of the inner shuttle body is an obtuse angle. The included angle between the blocking face and the inner edge face of the inner shuttle body is smaller than the included angle between the guide face and the inner edge face of the inner shuttle body. The sewing machine has the advantages that the probability of thread throwing and thread breaking in the sewing process can be effectively reduced, and the sewing quality is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of sewing machine accessories and relates to an inner shuttle structure of a sewing machine. Background Art

[0002] The rotary shuttle is an important component of the sewing machine. The rotary shuttle includes an inner shuttle and an outer shuttle rotatably nested outside the inner shuttle. The outer shuttle is provided with a shuttle tip, and a bobbin core for supplying the bottom line is sleeved on the central axis of the inner shuttle. When working, the shuttle tip of the outer shuttle hooks the upper thread loop and rotates and expands with the upper thread loop. When the shuttle tip carries the upper thread around the lowest point of the inner shuttle, the thread take-up rod rises rapidly and pulls the upper thread, so that the upper thread loop slides off the shuttle tip and interweaves with the bottom line in the inner shuttle bobbin core to form a lock stitch. In this process, when the upper thread loop slides off the shuttle tip, due to the inertia of high-speed rotation, the upper thread loop will swing and self-entangle after leaving the shuttle tip. The self-entangled upper thread loop is pulled by the thread take-up rod to form a thread knot, and is blocked in the needle eye of the cloth and cannot be completely reeled in, thus forming a thrown thread. In severe cases, the thread will break during the pulling process, affecting the sewing quality of the clothing. Summary of the invention

[0003] The purpose of the utility model is to solve the above problems in the existing technology and propose an inner shuttle structure of a sewing machine. The technical problem to be solved by the utility model is to effectively reduce the probability of thread throwing and thread breaking during sewing to improve the sewing quality.

[0004] The purpose of the utility model can be achieved through the following technical solutions:

[0005] An inner shuttle structure of a sewing machine comprises an inner shuttle body in the shape of a tube, the outer edge of the inner shuttle body having a needle drop groove and an anti-injury convex edge radially thereof, and is characterized in that a protrusion is provided on the inner edge of the inner shuttle body, and the protrusion and the anti-injury convex edge are located on the same side of the inner shuttle body, and the side of the protrusion close to and away from the needle drop groove respectively have a blocking surface and a guide surface intersecting with the inner edge surface of the inner shuttle body, and the guide surface and the blocking surface are smoothly transitionally connected, the angle between the guide surface and the inner edge surface of the inner shuttle body is an obtuse angle, and the angle between the blocking surface and the inner edge surface of the inner shuttle body is smaller than the angle between the guide surface and the inner edge surface of the inner shuttle body.

[0006] The inner shuttle structure of the sewing machine is provided with a protrusion on the side of the inner edge of the surface thread loop leaving the inner shuttle body. The longer surface thread loop can be automatically mounted on the protrusion when it reaches the thread-off position, so that the two strands of the surface thread loop are separated by the protrusion, thereby preventing the surface thread loop from swinging and self-entanglement. Subsequently, under the pulling action of the thread taking-up rod, the surface thread loop itself gradually shrinks. In addition, the guide surface and the blocking surface are smoothly transitioned and connected, the angle between the guide surface and the inner edge surface of the inner shuttle body is an obtuse angle, and the angle between the blocking surface and the inner edge surface of the inner shuttle body is smaller than the angle between the guide surface and the inner edge surface of the inner shuttle body, so that one strand of the surface thread loop is blocked and limited by the blocking surface located at the upper end of the protrusion, and the other strand of the thread gradually moves from the lower end of the protrusion to the upper end along the guide surface at the lower end of the protrusion, so that the shrunk thread loop can smoothly separate from the protrusion and the inner shuttle body, thereby effectively reducing the probability of thread throwing and thread breakage to improve the sewing quality.

[0007] In the above-mentioned inner shuttle structure of a sewing machine, the blocking surface and the guide surface are both smooth surfaces, the angle between the blocking surface and the inner edge surface of the inner shuttle body is a right angle or an obtuse angle, and the blocking surface and the guide surface are arranged to be inclined toward each other. By setting both the blocking surface and the guide surface as smooth surfaces, it is beneficial for the upper thread loop to move on the blocking surface and the guide surface, so that the upper thread loop can finally escape from the protrusion. At the same time, by setting the angle between the blocking surface and the inner edge surface of the inner shuttle body to a right angle or an obtuse angle, the blocking surface is made steeper, which is beneficial for the blocking thread loop to escape from the protrusion outward. In addition, by setting the blocking surface and the guide surface to be inclined toward each other, the protrusion is arranged to be small at the top and large at the bottom, which is more reasonable and also beneficial for the sleeve and escape of the upper thread loop.

[0008] In the above-mentioned inner shuttle structure of a sewing machine, the length of the blocking surface is smaller than the length of the guide surface. By setting the length of the blocking surface to be smaller than the length of the guide surface, the structure is more reasonable, so that the upper thread loop itself can be gradually reduced to a certain extent before it can be separated from the protrusion, and at the same time, the upper thread loop can be prevented from being retained on the protrusion.

[0009] In the above-mentioned inner shuttle structure of a sewing machine, there is a transition surface between the guide surface and the blocking surface, and the transition surface is an arc surface. By setting the transition surface as an arc surface, the transition surface is smoother and has an arc top, which is conducive to the temporary positioning of the upper thread loop on both sides of the transition surface and the ability to detach from the transition surface.

[0010] In the above-mentioned inner shuttle structure of a sewing machine, the protrusion is integrally formed on the inner edge of the inner shuttle body. By integrally forming the protrusion on the inner edge of the inner shuttle body, the molding can be done in one step, and the strength and durability of the parts are greatly improved.

[0011] In the inner shuttle structure of the sewing machine, the protrusion is welded and fixed on the inner edge of the inner shuttle body, so that the structural strength of the protrusion and the inner shuttle body after connection is high, and it is not easy to produce excessive deformation under the action of external force, and no additional connecting parts are required, and the weight of the two after connection is lighter.

[0012] In the above-mentioned inner shuttle structure of a sewing machine, the protrusion is threadedly connected to the inner edge of the inner shuttle body, so that the protrusion and the inner shuttle body can be manufactured separately, and at the same time has the advantages of simple structure, reliable connection, and convenient assembly and disassembly.

[0013] In the inner shuttle structure of the above-mentioned sewing machine, the inner end of the inner shuttle body has a strip bottom plate, and each of the two sides of the strip bottom plate has an opening, and both ends of the strip bottom plate have guide wire surfaces. On the one hand, the strip bottom plate can be used to set the central axis of the inner shuttle, and on the other hand, each of the two sides of the strip bottom plate has an opening, which can reduce the collision probability of the upper thread loop when moving. In addition, the guide wire surfaces are provided at both ends of the strip bottom plate, which can also guide the moving path of the upper thread loop, so that the upper thread loop can move along the inner edge of the inner shuttle body, so that the longer upper thread loop can automatically fit on the protrusion when it reaches the thread-off position.

[0014] In the above-mentioned inner shuttle structure of a sewing machine, the guide wire surface is triangular in shape, the guide wire surface close to the needle drop groove is inclined from the inside to the outside in a direction from close to the needle drop groove to the direction away from the needle drop groove, and the guide wire surface away from the needle drop groove is inclined from the outside to the inside in a direction from close to the needle drop groove to the direction away from the needle drop groove. The guide wire surface of the above-mentioned structure can better guide the upper thread loop to move along the inner edge of the inner shuttle body, so that the longer upper thread loop can be automatically set on the protrusion when it reaches the thread-off position.

[0015] In the above-mentioned inner shuttle structure of a sewing machine, there are two protrusions which are arranged adjacent to each other.

[0016] Compared with the prior art, the inner shuttle structure of the present sewing machine has the following advantages: a protrusion is provided on the inner edge side of the upper thread loop leaving the inner shuttle body, and the longer upper thread loop can automatically be mounted on the protrusion when it reaches the thread-off position, so that the two strands of the upper thread loop are separated by the protrusion, thereby preventing the upper thread loop from swinging and self-entanglement, and then under the pulling action of the thread taking-up rod, the upper thread loop itself gradually shrinks, and one strand of the upper thread loop is blocked and limited by the blocking surface located at the upper end of the protrusion, and the other strand of the upper thread gradually moves from the lower end of the protrusion to the upper end along the guide surface at the lower end of the protrusion, so that the shrunken thread loop can smoothly detach from the protrusion and the inner shuttle body, thereby effectively reducing the probability of thread throwing and thread breakage to improve the sewing quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional structural schematic diagram of the inner shuttle structure of the sewing machine in the first embodiment when in use.

[0018] Figure 2 It is a three-dimensional structural schematic diagram of the inner shuttle structure and the upper thread loop state of the sewing machine in the first embodiment.

[0019] Figure 3 yes Figure 2 A partial enlarged view of point A in the middle.

[0020] Figure 4 It is an exploded view of the inner shuttle structure of the sewing machine in the second embodiment.

[0021] Figure 5 It is a three-dimensional structural schematic diagram of the inner shuttle structure of the sewing machine in the third embodiment.

[0022] Figure 6 It is a three-dimensional structural schematic diagram of the inner shuttle structure of the sewing machine when the protrusion is removed and the upper thread loop state.

[0023] In the figure, 1, inner shuttle body; 1a, inner edge surface; 1b, strip bottom plate; 1b1, guide wire surface; 1c, opening; 1d, needle drop groove; 1e, convex edge; 2, bump; 2a, blocking surface; 2b, guide surface; 2c, transition surface; 3, outer shuttle; 3a, shuttle tip; 4, surface thread loop. DETAILED DESCRIPTION

[0024] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0025] Embodiment 1

[0026] An inner shuttle structure of a sewing machine, referring to Figure 1-3 and Figure 6 , including a cylindrical inner shuttle body 1, the outer edge of the inner shuttle body 1 has a needle drop groove 1d and an anti-injury convex edge 1e protruding along its radial direction, the inner edge of the inner shuttle body 1 is provided with a protrusion 2, and the protrusion 2 and the anti-injury convex edge 1e are located on the same side of the inner shuttle body 1, and the side of the protrusion 2 close to and away from the needle drop groove 1d respectively has a blocking surface 2a and a guide surface 2b intersecting with the inner edge surface 1a of the inner shuttle body 1, and the guide surface 2b and the blocking surface 2a are smoothly transitioned and connected, the angle between the guide surface 2b and the inner edge surface 1a of the inner shuttle body 1 is an obtuse angle, and the angle between the blocking surface 2a and the inner edge surface 1a of the inner shuttle body 1 is smaller than the angle between the guide surface 2b and the inner edge surface 1a of the inner shuttle body 1.

[0027] Further, refer to Figure 1-3 and Figure 6 The length of the blocking surface 2a is smaller than the length of the guiding surface 2b.

[0028] Furthermore, refer to Figure 1-3 and Figure 6The inner end of the inner shuttle body 1 has a strip bottom plate 1b, and there is an opening 1c on each side of the strip bottom plate 1b. Both ends of the strip bottom plate 1b have wire surfaces 1b1; the wire surfaces 1b1 are triangular in shape, and the wire surface 1b1 close to the needle drop groove 1d is inclined from the inside to the outside in a direction from close to the needle drop groove 1d to away from the needle drop groove 1d, and the wire surface 1b1 away from the needle drop groove 1d is inclined from the outside to the inside in a direction from close to the needle drop groove 1d to away from the needle drop groove 1d.

[0029] In this embodiment, preferably, the blocking surface 2a and the guiding surface 2b are both smooth surfaces, the angle between the blocking surface 2a and the inner edge surface 1a of the inner shuttle body 1 is a right angle or an obtuse angle, and the blocking surface 2a and the guiding surface 2b are inclined toward each other; preferably, there is a transition surface 2c between the guiding surface 2b and the blocking surface 2a, and the transition surface 2c is a curved surface; preferably, the protrusion 2 is integrally formed on the inner edge of the inner shuttle body 1.

[0030] The following describes the working principle of the inner shuttle structure of this sewing machine:

[0031] When working, the sewing machine needle is located on the outer edge side of the inner shuttle body 1, and the protrusion 2 is located on the inner edge surface 1a of the inner shuttle body 1 and is arranged on the side where the upper thread loop leaves. The upper thread loop 4 rotates and expands around the inner shuttle body 1 driven by the shuttle tip 3a of the outer shuttle 3. When the shuttle tip 3a brings the upper thread loop 4 around the lowest point of the inner shuttle body 1, the thread take-up rod rises rapidly to pull the upper thread, causing the upper thread loop 4 to slide off the shuttle tip 3a. At this time, the shuttle tip 3a of the outer shuttle 3 is located below the protrusion 2, and the root of the upper thread loop 4 is on the needle, that is, located above the protrusion 2 and on the outer edge side of the inner shuttle body 1. In addition, the length of the upper thread loop 4 is relatively long and the upper thread loop 4 has the inertia of moving around the inner edge of the inner shuttle body 1, so that the upper thread loop 4 can be automatically set on the protrusion 2 with a small upper part and a large lower part, so that the upper thread loop 4 is temporarily positioned on the protrusion 2, and at the same time, the two ends of the upper thread loop 4 The strands of thread can be separated by the protrusion 2, thereby preventing the upper thread loop 4 from swinging and self-entanglement. Subsequently, under the pulling action of the thread take-up rod, the upper thread loop 4 itself gradually shrinks, so that one strand of the upper thread loop 4 is blocked and limited by the blocking surface 2a located at the upper end of the protrusion 2. In addition, the guide surface 2b and the blocking surface 2a are smoothly connected by the transition surface 2c, and the angle between the guide surface 2b and the inner edge surface 1a of the inner shuttle body 1 is an obtuse angle. The other strand of the upper thread loop 4 gradually moves from the lower end of the protrusion 2 to the upper end along the smooth guide surface 2b at the lower end of the protrusion 2, so that the reduced thread loop can smoothly break away from the protrusion 2 and the inner shuttle body 1. Finally, the upper thread loop 4 is wrapped around the bottom line, the outer shuttle 3 is reversed and reset, and the thread take-up rod tightens the stitches, so that the interlacing point of the upper thread loop 4 and the bottom line is located in the center of the sewing material, and the feed dog pushes the sewing material to complete a stitch length, thereby effectively reducing the probability of thread throwing and thread breakage to improve sewing quality.

[0032] Embodiment 2

[0033] The structure and principle of this embodiment are basically the same as those of the first embodiment, except that: Figure 4 The protrusion 2 is threadedly connected to the inner edge of the inner shuttle body 1. A fixing plate is provided on the protrusion 2, and a positioning hole is provided on the fixing plate. A fixing hole with an internal thread is provided at a position corresponding to the positioning hole on the side wall of the inner shuttle body 1. The protrusion 2 is connected to the fixing hole of the inner shuttle body 1 by a bolt penetrating the positioning hole.

[0034] Embodiment 3

[0035] The structure and principle of this embodiment are basically the same as those of the first embodiment, except that: Figure 5 There are two protrusions 2 and they are arranged adjacent to each other.

[0036] Embodiment 4

[0037] The structure and principle of this embodiment are basically the same as those of the first embodiment, except that the protrusion 2 is welded and fixed to the inner edge of the inner shuttle body 1 (not shown in the figure).

[0038] The specific embodiments described herein are merely examples of the spirit of the present invention. A person skilled in the art of the present invention may make various modifications or additions to the specific embodiments described or replace them in a similar manner, but this will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. An inner shuttle structure of a sewing machine, comprising a cylindrical inner shuttle body (1), the outer edge of the inner shuttle body (1) having a needle drop groove (1d) and an anti-injury convex edge (1e) convexly arranged along its radial direction, characterized in that: The inner edge of the inner shuttle body (1) is provided with a protrusion (2), and the protrusion (2) and the anti-injury convex edge (1e) are located on the same side of the inner shuttle body (1), and the sides of the protrusion (2) close to and away from the needle drop groove (1d) respectively have a blocking surface (2a) and a guide surface (2b) intersecting with the inner edge surface (1a) of the inner shuttle body (1), and the guide surface (2b) and the blocking surface (2a) are smoothly transitionally connected, the angle between the guide surface (2b) and the inner edge surface (1a) of the inner shuttle body (1) is an obtuse angle, and the angle between the blocking surface (2a) and the inner edge surface (1a) of the inner shuttle body (1) is smaller than the angle between the guide surface (2b) and the inner edge surface (1a) of the inner shuttle body (1).

2. The inner shuttle structure of a sewing machine according to claim 1, characterized in that: The blocking surface (2a) and the guiding surface (2b) are both smooth surfaces, the angle between the blocking surface (2a) and the inner edge surface (1a) of the inner shuttle body (1) is a right angle or an obtuse angle, and the blocking surface (2a) and the guiding surface (2b) are arranged to be inclined toward each other.

3. The inner shuttle structure of a sewing machine according to claim 1, characterized in that: The length of the blocking surface (2a) is smaller than the length of the guiding surface (2b).

4. The inner shuttle structure of a sewing machine according to claim 1, characterized in that: A transition surface (2c) is provided between the guide surface (2b) and the blocking surface (2a), and the transition surface (2c) is a curved surface.

5. An inner shuttle structure of a sewing machine according to claim 1 or 2 or 3 or 4, characterized in that: The protrusion (2) is integrally formed on the inner edge of the inner shuttle body (1).

6. An inner shuttle structure of a sewing machine according to claim 1 or 2 or 3 or 4, characterized in that: The protrusion (2) is welded and fixed on the inner edge of the inner shuttle body (1).

7. An inner shuttle structure of a sewing machine according to claim 1 or 2 or 3 or 4, characterized in that: The protrusion (2) is threadedly connected to the inner edge of the inner shuttle body (1).

8. An inner shuttle structure of a sewing machine according to claim 1 or 2 or 3 or 4, characterized in that: The inner end of the inner shuttle body (1) has a strip bottom plate (1b), both sides of the strip bottom plate (1b) have an opening (1c), and both ends of the strip bottom plate (1b) have wire guide surfaces (1b1).

9. The inner shuttle structure of a sewing machine according to claim 8, characterized in that: The conductor surface (1b1) is triangular in shape, the conductor surface (1b1) close to the needle drop groove (1d) is inclined from the inside to the outside in a direction from close to the needle drop groove (1d) to away from the needle drop groove (1d), and the conductor surface (1b1) away from the needle drop groove (1d) is inclined from the outside to the inside in a direction from close to the needle drop groove (1d) to away from the needle drop groove (1d).

10. An inner shuttle structure of a sewing machine according to claim 1 or 2 or 3 or 4, characterized in that: There are two protrusions (2) which are arranged adjacent to each other.

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