Thread trimming mechanism

Abstract

The utility model belongs to the technical field of sewing machines, and particularly relates to a thread trimming mechanism which is arranged on a seat body of a sewing machine shell and comprises a motor, a gear transmission mechanism, a rotating shaft, a movable cutter and a fixed cutter, the motor is arranged on the rear side of the seat body, the rotating shaft is arranged on the seat body, the gear transmission mechanism comprises a driving gear and an eccentric transmission piece, and the driving gear is coaxially sleeved on a main shaft of the motor. The eccentric transmission part is arranged at one end of the rotating shaft and provided with gear teeth meshed with the driving gear, the movable cutter is arranged at the end, away from the eccentric transmission part, of the rotating shaft, the fixed cutter is arranged on the front side of the base, and the movable cutter and the fixed cutter are matched to cut off sewing threads. The thread trimming mechanism omits manual thread trimming operation, shortens the period and time consumption of sewing operation, and effectively improves the efficiency and the yield.

Description

Technical Field

[0001] This utility model belongs to the field of sewing machine technology, and in particular relates to a thread-cutting mechanism. Background Technology

[0002] A sewing machine is a machine that uses one or more sewing threads to create one or more stitches on fabric, allowing one or more layers of fabric to interweave or sew together. In the garment industry, the sewing machine needs to cut the thread after sewing. Traditional operation relies on manual thread cutting, which requires interrupting the sewing process, is time-consuming, and is prone to accidentally cutting fabric, increasing the scrap rate. Utility Model Content

[0003] The purpose of this invention is to provide a thread-cutting mechanism to solve the problem that manual thread cutting is time-consuming and reduces efficiency after sewing is completed in existing sewing machines.

[0004] To achieve the above objectives, this utility model provides a thread-cutting mechanism mounted on the base of a sewing machine. The mechanism includes a motor, a gear transmission mechanism, a rotating shaft, a moving blade, and a fixed blade. The motor is located at the rear of the base, and the rotating shaft is mounted on the base. The gear transmission mechanism includes a driving gear and an eccentric transmission component. The driving gear is coaxially mounted on the main shaft of the motor. The eccentric transmission component is located at one end of the rotating shaft and has teeth that mesh with the driving gear. The moving blade is located at the end of the rotating shaft away from the eccentric transmission component, and the fixed blade is located at the front of the base. The moving blade and the fixed blade cooperate to cut the sewing thread.

[0005] Furthermore, the eccentric transmission component is a quarter-segment sector gear.

[0006] Furthermore, a crank is fitted onto the end of the rotating shaft, and a connecting rod is hinged to the other end of the crank. A moving tool holder is connected to the end of the moving tool, and the moving tool holder is rotatably connected to the base. The moving tool holder is provided with an outwardly extending support rod, and the connecting rod is hinged to the support rod.

[0007] Furthermore, the moving tool holder includes a collar, and the base body is provided with a positioning seat on the side facing the moving tool holder. The center of the positioning seat is provided with a disc extending toward the collar, and a baffle is connected to the end of the disc. The collar of the moving tool holder is sleeved on the outer periphery of the disc and rotatably connected to the disc. The outer diameter of the baffle is larger than the inner diameter of the collar.

[0008] Furthermore, the outer surface of the moving blade is provided with a protruding boss, and one side of the boss is provided with an inclined cutting edge to form a boss cutting edge. The moving blade is provided with a guide port, a guide groove and the boss cutting edge in sequence from near to far on the side of the fixed blade. The guide groove is a groove with an open top, and its inlet end connects to the guide port and its outlet end extends to the boss cutting edge.

[0009] Furthermore, the fixed blade is detachably mounted on the bottom of the fixed blade holder of the base. One end of the fixed blade holder is provided with a through screw hole, and an adjusting bolt is installed in the screw hole. The bottom end of the adjusting bolt abuts against the top surface of the fixed blade.

[0010] The above-mentioned one or more technical solutions in the wire-cutting mechanism provided in this embodiment of the utility model have at least the following technical effects:

[0011] This thread-cutting mechanism is located below the sewing needle on the sewing machine. After the garment is sewn, the needle returns to its original position, and the sewing thread connected to the needle is positioned between the moving and fixed blades. A motor drives a drive gear to rotate, causing an eccentric transmission component to rotate, which in turn drives a shaft to rotate the moving blade. As the moving blade rotates, it moves the sewing thread until it engages with the fixed blade, cutting the thread automatically. After the thread is cut, the motor drives the moving blade to rotate back, resetting it for the next thread cut. This mechanism eliminates manual thread cutting, shortens the sewing cycle time, and effectively improves efficiency and yield. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the wire-cutting mechanism provided in an embodiment of the present invention.

[0014] Figure 2 Another structural diagram of the wire-cutting mechanism provided in an embodiment of this utility model.

[0015] Figure 3 This is a front view of the wire-cutting mechanism provided in an embodiment of the present utility model.

[0016] Figure 4 The diagram shows the moving blade holder and positioning seat of the wire cutting mechanism provided in this embodiment of the utility model.

[0017] Figure 5 An exploded view of the moving blade holder and positioning seat of the wire cutting mechanism provided in an embodiment of this utility model.

[0018] Figure 6 This is a structural diagram of the moving blade of the wire-cutting mechanism provided in an embodiment of the present utility model.

[0019] In the diagram, 100 is the base, 110 is the positioning seat, 111 is the disc, and 112 is the baffle.

[0020] 200. Electric motor

[0021] 300. Gear transmission mechanism; 310. Drive gear; 320. Eccentric transmission component.

[0022] 400. Shaft; 410. Crank; 420. Connecting rod.

[0023] 500. Moving blade; 510. Moving blade holder; 511. Support rod; 512. Collar; 520. Boss; 521. Boss cutting edge; 530. Guide port; 540. Guide groove.

[0024] 600. Fixed tool; 610. Fixed tool holder; 620. Adjusting bolt. Detailed Implementation

[0025] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the embodiments of this utility model, and should not be construed as limiting the utility model.

[0026] In the description of the embodiments of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0027] 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] In this embodiment of the invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment of the invention according to the specific circumstances.

[0029] In one embodiment of the wire-cutting mechanism of this utility model, please refer to... Figures 1 to 6 The thread-cutting mechanism, located on the base 100 of the sewing machine, includes a motor 200, a gear transmission mechanism 300, a rotating shaft 400, a moving blade 500, and a fixed blade 600. The motor 200 is located at the rear of the base 100, and the rotating shaft 400 is located on the base 100. The gear transmission mechanism 300 includes a drive gear 310 and an eccentric transmission component 320. The drive gear 310 is coaxially mounted on the main shaft of the motor 200. The eccentric transmission component 320 is located at one end of the rotating shaft 400 and has teeth that mesh with the drive gear 310. The moving blade 500 is located at the end of the rotating shaft 400 away from the eccentric transmission component 320, and the fixed blade 600 is located at the front of the base 100. The moving blade 500 and the fixed blade 600 cooperate to cut the sewing thread.

[0030] Specifically, this thread-cutting mechanism is located below the sewing needle of the sewing machine. After the garment is sewn, the needle returns to its original position, and the sewing thread connected to the needle is positioned between the moving blade 500 and the fixed blade 600. The motor 200 drives the drive gear 310 to rotate, causing the eccentric transmission component 320, which in turn drives the rotating shaft 400 to rotate the moving blade 500. As the moving blade 500 rotates, it moves the sewing thread until it engages with the fixed blade 600, cutting the thread and achieving automatic thread cutting. The motor 200 and gear transmission mechanism 300 ensure the accuracy of the moving blade 500's rotation. After the thread is cut, the motor 200 drives the moving blade 500 to rotate back, resetting it for the next thread cutting. This thread-cutting mechanism eliminates manual thread cutting, shortens the sewing cycle time, and effectively improves efficiency and yield.

[0031] For further details, please refer to... Figure 2 The eccentric transmission component 320 is a quarter-sized sector gear. Specifically, the quarter-sized sector gear effectively reduces the area occupied by the gear transmission mechanism 300; and the range of teeth of the eccentric transmission component 320 limits the rotation stroke of the moving tool 500, avoiding the possibility that the moving tool 500 might collide with the fixed tool 600 after rotating one revolution.

[0032] For further details, please refer to... Figure 2 and Figure 3A crank 410 is fitted onto the end of the rotating shaft 400, and a connecting rod 420 is hinged to the other end of the crank 410. A moving tool holder 510 is connected to the end of the moving tool 500, and the moving tool holder 510 is rotatably connected to the base 100. The moving tool holder 510 has an outwardly extending support rod 511, and the connecting rod 420 is hinged to the support rod 511. Specifically, the crank 410 is clamped and fitted onto the end of the rotating shaft 400. When the motor 200 drives the gear transmission mechanism 300 to rotate, it drives the rotating shaft 400 to synchronously drive the crank 410 to rotate. The crank 410 drives the connecting rod 420 to move, thereby driving the moving tool holder 510 and the moving tool 500 to rotate on the base 100. The crank 410 and the connecting rod 420 are hinged to prevent interference when the moving tool holder 410 rotates.

[0033] For further details, please refer to... Figure 4 and Figure 5 The movable tool holder 510 includes a collar 512. A positioning seat 110 is provided on the side of the base 100 facing the movable tool holder 510. A disk 111 extending towards the collar 512 is located at the center of the positioning seat 110. A baffle 112 is connected to the end of the disk 111. The collar 512 of the movable tool holder is fitted around the outer circumference of the disk 111 and rotatably connected to it. The outer diameter of the baffle 112 is larger than the inner diameter of the collar 512. Specifically, the positioning seat 110 and the baffle 112 restrict the axial displacement of the collar 512. The movable tool holder 510 rotates around the axis of the disk 111 via the collar 512, preventing radial displacement of the movable tool holder 510 and effectively preventing misalignment between the fixed tool 600 and the movable tool 500, thus ensuring the stability of the movable tool 500's rotation.

[0034] For further details, please refer to... Figure 6 The outer surface of the moving blade 500 is provided with a protruding boss 520. One side of the boss 520 is provided with an inclined cutting edge to form a boss cutting edge 521. On the side of the moving blade 500 near the fixed blade 600, a guide port 530, a guide groove 540 and a boss cutting edge 521 are provided in sequence from near to far. The guide groove 540 is a groove with an open top. Its inlet end connects to the guide port 530 and its outlet end extends to the boss cutting edge 521. Specifically, the motor 200 drives the moving blade 500 to rotate toward the fixed blade 600. The guide port 530 guides the sewing thread into the guide port 530 and moves synchronously with the moving blade 500, and constrains the sewing thread to prevent it from detaching from the moving blade 500. When the guide port 530 rotates to below the fixed blade 600, the blade of the fixed blade 600 abuts against the sewing thread. As the moving blade 500 rotates, the blade of the fixed blade 600 abuts against the sewing thread and enters the guide groove 540, preventing the sewing thread from deviating during movement, until the sewing thread contacts the boss blade 521. The blade of the fixed blade 600 and the boss blade 521 engage to achieve automatic and precise cutting of the sewing thread.

[0035] For further details, please refer to... Figure 1The fixed blade 600 is detachably mounted on the bottom of the fixed blade holder 610 of the base. One end of the fixed blade holder 610 has a through screw hole, into which an adjusting bolt 620 is installed. The bottom end of the adjusting bolt 620 abuts against the top surface of the fixed blade 600. Specifically, one end of the fixed blade 600 is locked and fixed to the bottom of the fixed blade holder 610 by a locking device. When the fixed blade 600 wears down due to long-term use, causing a reduction in its engagement force with the boss cutting edge 521, the locking device can be loosened to loosen the fixed blade 600. Then, the adjusting bolt 620 can be turned downwards, causing the bottom end of the adjusting bolt 620 to push the fixed blade 600 downwards, allowing the fixed blade 600 to move downwards stably. After the fixed blade 600 moves downwards, its cutting edge re-engages tightly with the side of the boss cutting edge 521, thereby increasing the engagement force. After adjustment, the locking device is tightened again to fix the fixed blade 600. The adjusting bolt 620 can effectively reduce the replacement frequency of vulnerable parts of the fixed tool 600, thereby reducing maintenance costs. The upper and lower limit design of the locking part and the adjusting bolt 620 ensures that the fixed tool 600 remains stably on the fixed tool holder 510 during and after adjustment.

[0036] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A thread-cutting mechanism, disposed on the base of a sewing machine, characterized in that, The device includes a motor, a gear transmission mechanism, a rotating shaft, a moving blade, and a fixed blade. The motor is located at the rear of the base, and the rotating shaft is mounted on the base. The gear transmission mechanism includes a driving gear and an eccentric transmission component. The driving gear is coaxially mounted on the main shaft of the motor. The eccentric transmission component is located at one end of the rotating shaft and has teeth that mesh with the driving gear. The moving blade is located at the end of the rotating shaft away from the eccentric transmission component, and the fixed blade is located at the front of the base. The moving blade and the fixed blade cooperate to cut the sewing thread.

2. The wire-cutting mechanism according to claim 1, characterized in that: The eccentric transmission component is a quarter-segment sector gear.

3. The wire-cutting mechanism according to claim 1, characterized in that: A crank is fitted at one end of the rotating shaft, and a connecting rod is hinged to the other end of the crank. A moving tool holder is connected to the end of the moving tool, and the moving tool holder is rotatably connected to the base. The moving tool holder is provided with an outwardly extending support rod, and the connecting rod is hinged to the support rod.

4. The wire-cutting mechanism according to claim 3, characterized in that: The moving tool holder includes a collar, and the base body has a positioning seat on the side facing the moving tool holder. The center of the positioning seat has a disc extending toward the collar, and the end of the disc is connected to a baffle. The collar of the moving tool holder is sleeved on the outer circumference of the disc and rotatably connected to the disc. The outer diameter of the baffle is larger than the inner diameter of the collar.

5. The wire-cutting mechanism according to any one of claims 1 to 4, characterized in that: The outer surface of the moving blade is provided with a protruding boss. One side of the boss is provided with an inclined cutting edge to form a boss cutting edge. The moving blade is provided with a guide port, a guide groove and the boss cutting edge in sequence from near to far on the side of the fixed blade. The guide groove is a groove with an open top. Its inlet end connects to the guide port and its outlet end extends to the boss cutting edge.

6. The wire-cutting mechanism according to claim 2, characterized in that: The fixed blade is detachably mounted on the bottom of the fixed blade holder of the base. One end of the fixed blade holder is provided with a through screw hole, and an adjusting bolt is installed in the screw hole. The bottom end of the adjusting bolt abuts against the top surface of the fixed blade.

Images