Cloth feeding mechanism of edge-covering sewing machine

Abstract

The utility model provides a cloth feeding mechanism of a hemming sewing machine, and belongs to the technical field of sewing machines. The edge covering sewing machine solves the technical problems that when an existing edge covering sewing machine covers edges, indentations are generated, and cloth feeding is not stable. According to the cloth feeding mechanism of the hemming sewing machine, an upper rotating shaft and an upper walking wheel are connected through an upper one-way needle bearing, a lower rotating shaft and a lower walking wheel are connected through a lower one-way needle bearing, the lower end of an upper crank can slide in a reciprocating mode along a long-strip-shaped hole of the upper crank, and a presser foot is fixedly connected to the front side face of an upper support. The upper end of the upper support is fixedly connected with an adjusting rod capable of adjusting the height of the upper support. The upper one-way needle bearing and the lower one-way needle bearing are arranged, so that wrinkles or creases of fabrics due to different linear speeds of the upper walking wheel and the lower walking wheel are avoided; the adjusting rod, the adjusting nut and the upper support are matched to adaptively adjust the gap between the upper walking wheel and the lower walking wheel, the fabric does not generate indentations at the edge covering position, and the attractiveness of an edge-covered product is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of sewing machines, in particular to a cloth feeding mechanism of an overlock sewing machine. Background Art

[0002] The hemming sewing machine is used to hem the edges of flexible fabrics of a certain thickness, which not only makes such fabrics more beautiful but also increases the strength of the fabrics. Traditional hemming sewing machines use a presser foot to press the flexible fabric against the work surface during the hemming process, resulting in obvious dents on the edges of the fabric after hemming.

[0003] In this regard, the invention patent with patent number 201310268652.9 discloses a three-dimensional hemming sewing machine, which is provided with an upper roller and a lower roller. The upper roller is driven downward by a pressing pedal, a push rod, a second reversing rod, a reversing shaft, a first reversing rod, a vertical support plate, a horizontal support plate and a roller shaft, thereby pressing the flexible fabric between the upper roller and the lower roller. The upper roller and the lower roller are respectively driven by small motors to realize the movement of the flexible fabric.

[0004] The above-mentioned three-dimensional hemming sewing machine adopts the design of upper and lower rollers, which increases the contact area with the flexible fabric, thereby avoiding the generation of dents to a certain extent or making the generated dents smaller in amplitude. However, the three-dimensional hemming sewing machine needs to manually step on the pressing pedal when working, and the force and amplitude of each manual stepping are different. If the stepping is too heavy or the amplitude is too large, the amplitude and force of the upper roller pressing the flexible fabric downward will be large, and it is likely to produce larger and deeper dents on the edge of the flexible fabric. In addition, the difference in the force and amplitude of each pressing will also lead to different quality of the product after hemming and lower stability. Furthermore, the upper roller and the lower roller are driven by independent small motors respectively, and according to their attached Figure 3 It can be clearly seen that the diameters of the upper roller and the lower roller are different, so it is difficult to control the linear speeds of the upper roller and the lower roller to be the same. The different linear speeds of the side walls of the upper roller and the lower roller will cause the upper and lower sides of the flexible fabric to move at different speeds, thereby causing the flexible fabric to curl or form creases, affecting the hemming effect. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model aims to provide a cloth feeding mechanism for an overlock sewing machine which has no dents and has more stable cloth feeding.

[0006] The purpose of the utility model can be achieved through the following technical solutions:

[0007] A cloth feeding mechanism of an overlock sewing machine comprises an upper bracket, a lower bracket, and an upper feeding wheel and a lower feeding wheel arranged in parallel, wherein the fabric passes through a gap between the upper feeding wheel and the lower feeding wheel, and is characterized in that an upper rotating shaft is rotatably mounted on the upper bracket, an upper feeding wheel is sleeved on the upper rotating shaft, and the upper rotating shaft and the upper feeding wheel are connected via an upper one-way needle bearing; one end of the upper rotating shaft extends out of the upper bracket and is fixedly connected to the middle part of the upper crank, the upper end of the upper crank is hinged to the front end of the connecting rod, and the lower end of the upper crank is connected to the upper end of the lower crank; the lower rotating shaft is rotatably mounted on the lower bracket, and the lower rotating shaft is sleeved with the lower feeding wheel. The lower rotating shaft and the lower feeding wheel are connected by a lower one-way needle bearing; the lower end of the lower crank is fixedly connected to the fixing sleeve of the lower rotating shaft or the lower one-way needle bearing, and the lower crank is provided with a long hole, and the length direction of the long hole is parallel to the length direction of the lower crank; a connecting piece is installed at the lower end of the upper crank, and the connecting piece can slide back and forth along the long hole; a presser foot is fixedly connected to the front side of the upper bracket, and an adjusting rod is fixedly connected to the upper end of the upper bracket, and the adjusting rod passes through the body of the overlock sewing machine and extends from the upper end of the body, and the upper end of the adjusting rod is threadedly connected to an adjusting nut, and the height of the upper bracket can be adjusted by rotating the adjusting nut.

[0008] The overlock sewing machine comprises a base, a work surface and a body, wherein the work surface is mounted on the base, and the body is mounted on the work surface. A window is arranged on the work surface, and the upper edge of the lower feeding wheel passes through the window and is located on the upper side of the work surface.

[0009] The cloth feeding mechanism realizes unidirectional rotation of the upper feeding wheel and the lower feeding wheel by arranging an upper unidirectional needle roller bearing and a lower unidirectional needle roller bearing, thereby driving the fabric to move. The cloth feeding mechanism realizes synchronous rotation of the upper feeding wheel and the lower feeding wheel by cooperating with the upper crank and the lower crank, thereby driving the fabric to move backward along the worktable. In the cloth feeding mechanism, even if the linear velocity of the outer peripheral surface of the upper feeding wheel is greater than the linear velocity of the outer peripheral surface of the lower feeding wheel, since the lower feeding wheel is connected to the rotating shaft through the lower unidirectional needle roller bearing, the lower feeding wheel can rotate backward faster under the action of friction, thereby avoiding wrinkles or folds in the fabric due to the different linear velocity of the upper and lower feeding wheels, making the cloth feeding of the cloth feeding mechanism more stable, and making the hemming sewing machine have a better hemming effect.

[0010] The above-mentioned adjusting rod, adjusting nut and upper bracket cooperate to adaptively adjust the gap between the upper feeding wheel and the lower feeding wheel according to fabric parameters such as fabric thickness and fabric elasticity. Under the premise of ensuring that the upper and lower feeding wheels cooperate to stably transport the fabric, no indentation will be generated at the hemming part of the fabric, thereby improving the aesthetics of the product after hemming. And because the gap between the upper feeding wheel and the lower feeding wheel can remain unchanged after adjustment, it ensures that the pressure of the upper feeding wheel and the lower feeding wheel on the fabric during the entire hemming process is relatively constant, so that the product after hemming has better consistency and better quality.

[0011] In the above-mentioned cloth feeding mechanism of the overlock sewing machine, the upper feeding wheel and the lower feeding wheel can rotate in opposite directions.

[0012] The upper feeding wheel and the lower feeding wheel which can rotate in opposite directions can jointly drive the fabric to move backwards during the fabric feeding process, and the stability is high.

[0013] In the above-mentioned cloth feeding mechanism of an overlock sewing machine, the upper one-way needle roller bearing and the lower one-way needle roller bearing both include a fixed sleeve and an outer ring, the fixed sleeve is fixedly connected to the corresponding upper rotating shaft or lower rotating shaft, the fixed sleeve and the outer ring are rotatably connected in one direction, and the outer ring is tightly connected to the corresponding upper feeding step wheel and lower feeding step wheel.

[0014] Since the upper sending step wheel is fixedly connected to the outer ring and the fixed sleeve is fixedly connected to the upper rotating shaft, the upper sending step wheel and the corresponding outer ring always rotate synchronously, and the upper rotating shaft and the corresponding fixed sleeve always rotate synchronously. Similarly, the lower sending step wheel and the corresponding outer ring always rotate synchronously, and the lower rotating shaft and the corresponding fixed sleeve always rotate synchronously.

[0015] like Figure 8 As shown, when the connecting rod pushes the upper crank to swing forward (as shown by arrow A'), the upper crank drives the upper rotating shaft and the fixed sleeve to rotate clockwise (as shown by arrow D'). Since the upper one-way needle roller bearing is locked when the fixed sleeve rotates clockwise relative to the outer ring, the outer ring and the upper feeding wheel will rotate clockwise synchronously with the lower rotating shaft (as shown by arrow C'); at the same time, the upper crank swinging forward will drive the lower crank to swing backward (as shown by arrow B'), and the lower crank swinging backward will drive the lower rotating shaft and the fixed sleeve to rotate counterclockwise (as shown by arrow F'). Since the lower one-way needle roller bearing is locked when the fixed sleeve rotates counterclockwise relative to the outer ring, the outer ring and the lower feeding wheel will rotate counterclockwise synchronously with the lower rotating shaft (as shown by arrow E').

[0016] like Fig. 9As shown, when the connecting rod pulls the upper crank to swing backward (as shown by arrow A”), the upper crank drives the upper rotating shaft and the fixed sleeve to rotate counterclockwise (as shown by arrow D”). Since the upper one-way needle bearing is smooth and not locked when the fixed sleeve rotates counterclockwise relative to the outer ring, the outer ring and the upper feeding wheel will remain stationary or rotate clockwise driven by the inertia of the fabric (as shown by arrow C”); at the same time, the upper crank swinging backward will drive the lower crank to swing forward (as shown by arrow B”), and the lower crank swinging forward will drive the lower rotating shaft and the fixed sleeve to rotate clockwise (as shown by arrow F”). Since the lower one-way needle bearing is smooth and not locked when the fixed sleeve rotates clockwise relative to the outer ring, the outer ring and the lower feeding wheel will remain stationary or rotate counterclockwise driven by the inertia of the fabric (as shown by arrow E”).

[0017] Above Figure 8 and Fig. 9 The arrow O in the figure is the moving direction of the fabric.

[0018] In the above-mentioned cloth feeding mechanism of the overlock sewing machine, small protrusions are evenly distributed on the outer peripheral surfaces of the upper feeding wheel and the lower feeding wheel.

[0019] The design of the small protrusions can increase the friction between the upper and lower feeding wheels and the fabric, so that the fabric feeding mechanism can convey the fabric more smoothly.

[0020] In the above-mentioned cloth feeding mechanism of an overlock sewing machine, the connecting member is a pin shaft, and the lower part of the upper crank is provided with at least two pin holes along the length direction, and the pin shaft can pass through the pin hole and the long hole and slide back and forth relative to the long hole.

[0021] The design of multiple pin holes can adjust the rotation amplitude of the lower crank as needed, thereby adjusting the rotation angle of the lower feeding wheel and adjusting the linear speed of the outer peripheral surface of the lower feeding wheel, thereby controlling the linear speed between the upper and lower feeding wheels, making the linear speeds of the two closer, and improving the smoothness of the fabric conveying process. Furthermore, the above-mentioned connecting piece can also be a columnar protrusion directly formed on the lower part of the upper crank.

[0022] In the above-mentioned cloth feeding mechanism of an overlock sewing machine, the presser foot includes a connecting plate, a foot handle and a pressing plate, the two ends of the foot handle are fixedly connected to the connecting plate and the pressing plate respectively, the connecting plate is fixedly connected to the front side of the upper bracket, the pressing plate can be pressed on the upper surface of the fabric, and a needle hole for the needle and thread to pass through is provided on the pressing plate, and the lower side of the pressing plate is higher than the lower edge of the upper feeding wheel.

[0023] Since this overlock sewing machine is mainly used for overlocking thicker and more elastic fabrics, the lower side of the pressing plate is higher than the lower edge of the upper feed wheel, which can ensure that the pressing plate can be pressed on the upper side of the fabric, so that the needle and thread can sew the overlock normally, and can ensure that excessive pressure will not be applied to the fabric to cause indentations.

[0024] In the above-mentioned cloth feeding mechanism of an overlock sewing machine, waist-shaped holes are provided on both sides of the connecting plate, the length direction of the waist-shaped holes is parallel to the vertical direction, and a mounting hole matching the waist-shaped holes is provided on the front side surface of the upper bracket, and the connecting plate and the upper bracket are fixedly connected by fasteners.

[0025] The waist-shaped hole design can fine-tune the height of the presser foot as needed, ensuring that the presser foot can work normally without causing indentations on the upper side of the fabric.

[0026] In the above-mentioned cloth feeding mechanism of an overlock sewing machine, at least two guide holes are provided on the lower bracket, guide rods are inserted into the guide holes, positioning holes that can be connected to the guide holes are provided on the front side wall and / or the rear side wall of the lower bracket, positioning screws for fixing the guide rods and the lower bracket are provided in the positioning holes, and the lower end of the guide rod is fixedly connected to the tugboat bracket.

[0027] The guide rod cooperates with the positioning screw to adjust and fix the lower bracket and the guide rod, and the height of the lower bracket can be fine-tuned as needed, thereby controlling the height of the lower feeding wheel protruding from the work surface, making the feeding process of the feeding mechanism smoother and more stable.

[0028] Compared with the prior art, the technical effects of the utility model are:

[0029] 1. The utility model realizes the unidirectional rotation of the upper and lower feeding wheels by arranging the upper and lower unidirectional needle bearings, thereby driving the fabric to move. The cloth feeding mechanism realizes the synchronous rotation of the upper and lower feeding wheels by the cooperation of the upper crank and the lower crank, thereby driving the fabric to move backward along the work surface.

[0030] 2. In the utility model, even if the linear speed of the outer peripheral surface of the upper feeding wheel is greater than the linear speed of the outer peripheral surface of the lower feeding wheel, since the lower feeding wheel is connected to the rotating shaft through the lower one-way needle bearing, the lower feeding wheel can rotate backward faster under the action of friction, thereby avoiding wrinkles or creases on the fabric due to the different linear speeds of the upper and lower feeding wheels, making the fabric feeding of the feeding mechanism more stable and the hemming sewing machine having a better hemming effect.

[0031] 3. The adjustment rod, the adjustment nut and the upper bracket in the utility model cooperate to adaptively adjust the gap between the upper feeding wheel and the lower feeding wheel according to fabric parameters such as fabric thickness and fabric elasticity. Therefore, on the premise of ensuring that the upper and lower feeding wheels cooperate to stably transport the fabric, no indentation will be generated at the hemming of the fabric, thereby improving the aesthetics of the product after hemming.

[0032] 4. The utility model ensures that the gap between the upper feeding wheel and the lower feeding wheel remains unchanged after adjustment, thereby ensuring that the pressure exerted by the upper feeding wheel and the lower feeding wheel on the fabric is relatively constant during the entire hemming process, so that the hemmed product has better consistency and better quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0034] Figure 2 The utility model is a cross-sectional view Figure 1 .

[0035] Figure 3 The utility model is a cross-sectional view Figure 2 .

[0036] Figure 4 It is a schematic diagram of the explosion structure at the upper delivery step wheel of the utility model.

[0037] Figure 5 It is a schematic diagram of the explosion structure at the lower delivery step wheel of the utility model.

[0038] Figure 6 It is a structural schematic diagram of the upper bracket of the utility model.

[0039] Figure 7 It is a structural schematic diagram of a presser foot of the utility model.

[0040] Figure 8 It is a schematic diagram of the rotation direction of each component when the connecting rod of the utility model moves forward.

[0041] Fig. 9 It is a schematic diagram of the rotation direction of each component when the connecting rod of the utility model moves backward.

[0042] In the figure, 1, upper bracket; 11, upper feeding wheel; 12, upper one-way needle bearing; 13, upper rotating shaft; 14, mounting hole; 2, lower bracket; 21, lower feeding wheel; 22, lower one-way needle bearing; 23, lower rotating shaft; 24, guide hole; 25, positioning hole; 3, upper crank; 31, connecting piece; 4, lower crank; 41, long hole; 5, connecting rod; 6, presser foot; 61, connecting plate; 611, waist-shaped hole; 62, foot handle; 63, press plate; 631, needle hole; 7, adjusting rod; 71, adjusting nut; 8, guide rod; 81, tugboat bracket; 9, fabric; 101, fixing sleeve; 102, outer ring. DETAILED DESCRIPTION

[0043] 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.

[0044] The cloth feeding mechanism of the overlock sewing machine comprises an upper bracket 1, a lower bracket 2, and an upper feeding wheel 11 and a lower feeding wheel 21 arranged in parallel, the fabric 9 passes through the gap between the upper feeding wheel 11 and the lower feeding wheel 21, an upper rotating shaft 13 is rotatably mounted on the upper bracket 1, the upper rotating shaft 13 is sleeved with the upper feeding wheel 11, and the upper rotating shaft 13 and the upper feeding wheel 11 are connected by an upper one-way needle bearing 12; one end of the upper rotating shaft 13 extends out of the upper bracket 1 and is fixedly connected to the middle part of the upper crank 3, the upper end of the upper crank 3 is hinged to the front end of the connecting rod 5, and the lower end of the upper crank 3 is connected to the upper end of the lower crank 4; a lower rotating shaft 23 is rotatably mounted on the lower bracket 2, the lower rotating shaft 23 is sleeved with the lower feeding wheel 21, and the lower rotating shaft 23 is sleeved with the lower feeding wheel 21. The shaft 23 and the lower feeding wheel 21 are connected through the lower one-way needle bearing 22; the lower end of the lower crank 4 is fixedly connected to the fixing sleeve 101 of the lower rotating shaft 23 or the lower one-way needle bearing 22, and the lower crank 4 is provided with an elongated hole 41, the length direction of the elongated hole 41 is parallel to the length direction of the lower crank 4; the lower end of the upper crank 3 is installed with a connecting piece 31, and the connecting piece 31 can slide back and forth along the elongated hole 41; the front side of the upper bracket 1 is fixedly connected with a presser foot 6, and the upper end of the upper bracket 1 is fixedly connected with an adjusting rod 7, the adjusting rod 7 penetrates the body of the hemming sewing machine and extends from the upper end of the body, and the upper end of the adjusting rod 7 is threadedly connected with an adjusting nut 71, and the height of the upper bracket 1 can be adjusted by rotating the adjusting nut 71. The hemming sewing machine includes a base, a work surface and a body, the work surface is installed on the base, and the body is installed on the work surface, and a window is provided on the work surface, and the upper edge of the lower feeding wheel 21 passes through the window and is located on the upper side of the work surface.

[0045] The cloth feeding mechanism realizes the unidirectional rotation of the upper feeding wheel 11 and the lower feeding wheel 21 by setting the upper one-way needle roller bearing 12 and the lower one-way needle roller bearing 22, thereby driving the fabric 9 to move. The cloth feeding mechanism realizes the synchronous rotation of the upper feeding wheel 11 and the lower feeding wheel 21 by the cooperation of the upper crank 3 and the lower crank 4, thereby driving the fabric 9 to move backward along the work surface; in the cloth feeding mechanism, even if the linear velocity of the outer peripheral surface of the upper feeding wheel 11 is greater than the linear velocity of the outer peripheral surface of the lower feeding wheel 21, since the lower feeding wheel 21 is connected to the rotating shaft through the lower one-way needle roller bearing 22, the lower feeding wheel 21 can rotate backward faster under the action of friction, thereby avoiding the fabric 9 from wrinkling or creases due to the different linear velocities of the upper and lower feeding wheels 21, making the cloth feeding mechanism The cloth is more stable, so that the hemming sewing machine has a better hemming effect; the above-mentioned adjusting rod 7, adjusting nut 71 and upper bracket 1 cooperate to adaptively adjust the gap between the upper feeding step wheel 11 and the lower feeding step wheel 21 according to the fabric 9 parameters such as the thickness of the fabric 9 and the elasticity of the fabric 9, so that on the premise of ensuring that the upper and lower feeding step wheels 21 cooperate to stably transport the fabric 9, the fabric 9 will not produce indentations at the hemming part, thereby improving the aesthetics of the product after hemming; and because the gap between the upper feeding step wheel 11 and the lower feeding step wheel 21 can remain unchanged after adjustment, it is ensured that the pressure of the upper feeding step wheel 11 and the lower feeding step wheel 21 on the fabric 9 during the entire hemming process is relatively constant, so that the product after hemming has better consistency and better quality.

[0046] The upper feeding wheel 11 and the lower feeding wheel 21 in the cloth feeding mechanism are rotatable in opposite directions. The upper feeding wheel 11 and the lower feeding wheel 21, which are rotatable in opposite directions, can work together to drive the cloth to move backward during the cloth feeding process, and have high stability. Further, the upper one-way needle roller bearing 12 and the lower one-way needle roller bearing 22 each include a fixed sleeve 101 and an outer ring 102, the fixed sleeve 101 is fixedly connected to the corresponding upper rotating shaft 13 or the lower rotating shaft 23, the fixed sleeve 101 and the outer ring 102 are rotatably connected in one direction, and the outer ring 102 is tightly connected to the corresponding upper feeding wheel 11 and the lower feeding wheel 21. Since the upper sending step wheel 11 is fixedly connected to the outer ring 102, and the fixed sleeve 101 is fixedly connected to the upper rotating shaft 13, the upper sending step wheel 11 and the corresponding outer ring 102 always rotate synchronously, and the upper rotating shaft 13 and the corresponding fixed sleeve 101 always rotate synchronously. Similarly, the lower sending step wheel 21 and the corresponding outer ring 102 always rotate synchronously, and the lower rotating shaft 23 and the corresponding fixed sleeve 101 always rotate synchronously.

[0047] like Figure 8As shown, when the connecting rod 5 pushes the upper crank 3 to swing forward (as shown by arrow A'), the upper crank 3 drives the upper rotating shaft 13 and the fixed sleeve 101 to rotate clockwise (as shown by arrow D'). Since the upper one-way needle bearing 12 is locked when the fixed sleeve 101 rotates clockwise relative to the outer ring 102, the outer ring 102 and the upper stepping wheel 11 will rotate clockwise synchronously with the lower rotating shaft 23 (as shown by arrow C'); at the same time, the upper crank 3 swinging forward will drive the lower crank 4 to swing backward (as shown by arrow B'), and the lower crank 4 swinging backward will drive the lower rotating shaft 23 and the fixed sleeve 101 to rotate counterclockwise (as shown by arrow F'). Since the lower one-way needle bearing 22 is locked when the fixed sleeve 101 rotates counterclockwise relative to the outer ring 102, the outer ring 102 and the lower stepping wheel 21 will rotate counterclockwise synchronously with the lower rotating shaft 23 (as shown by arrow E').

[0048] like Fig. 9 As shown, when the connecting rod 5 pulls the upper crank 3 to swing backward (as shown by arrow A”), the upper crank 3 drives the upper rotating shaft 13 and the fixed sleeve 101 to rotate counterclockwise (as shown by arrow D”). Since the upper one-way needle bearing 12 rotates smoothly and not locked relative to the outer ring 102 in the counterclockwise direction of the fixed sleeve 101, the outer ring 102 and the upper feeding wheel 11 will remain stationary or rotate clockwise (as shown by arrow C”) driven by the inertia of the fabric 9; at the same time, the upper crank 3 moves backward. The swinging upper crank 3 drives the lower crank 4 to swing forward (as shown by arrow B”), and the swinging lower crank 4 drives the lower rotating shaft 23 and the fixed sleeve 101 to rotate clockwise (as shown by arrow F”). Since the lower one-way needle bearing 22 is smooth and not locked when the fixed sleeve 101 rotates clockwise relative to the outer ring 102, the outer ring 102 and the lower stepping wheel 21 will remain stationary or rotate counterclockwise (as shown by arrow E”) driven by the inertia of the fabric 9. Figure 8 and Fig. 9 The arrow O in the figure is the moving direction of the fabric.

[0049] Further, small protrusions are evenly distributed on the outer circumferences of the upper feeding wheel 11 and the lower feeding wheel 21. The design of the above-mentioned small protrusions can increase the friction between the upper and lower feeding wheels 21 and the fabric 9, so that the fabric feeding mechanism can convey the fabric 9 more smoothly.

[0050] like Figure 3 and Figure 4As shown, the connecting member 31 is a pin shaft, and the lower part of the upper crank 3 is provided with at least two pin holes along the length direction, and the pin shaft can pass through the pin hole and the long hole 41 and slide back and forth relative to the long hole 41. The design of multiple pin holes can adjust the rotation amplitude of the lower crank 4 as needed, thereby adjusting the rotation angle of the lower feeding step wheel 21 and adjusting the linear speed of the outer peripheral surface of the lower feeding step wheel 21, thereby controlling the linear speed between the upper and lower feeding step wheels 21, making the linear speeds of the two closer, and improving the smoothness of the fabric 9 during transportation. Further, the above-mentioned connecting member 31 can also be a columnar protrusion directly formed on the lower part of the upper crank 3.

[0051] like Figure 6 and Figure 7 As shown, the presser foot 6 includes a connecting plate 61, a foot handle 62 and a pressing plate 63, the two ends of the foot handle 62 are fixedly connected to the connecting plate 61 and the pressing plate 63 respectively, the connecting plate 61 is fixedly connected to the front side of the upper bracket 1, the pressing plate 63 can be pressed on the upper surface of the fabric 9, and the pressing plate 63 is provided with a needle hole 631 for the needle and thread to pass through, and the lower side of the pressing plate 63 is higher than the lower edge of the upper feeding wheel 11; waist-shaped holes 611 are provided on the left and right sides of the connecting plate 61, and the length direction of the waist-shaped holes 611 is parallel to the vertical direction, and a mounting hole 14 matching the waist-shaped holes 611 is provided on the front side of the upper bracket 1, and the connecting plate 61 and the upper bracket 1 are fixedly connected by fasteners. Since this overlock sewing machine is mainly used for overlocking thicker and more elastic fabrics 9, the lower side of the pressing plate 63 is higher than the lower edge of the upper feed wheel 11, which can ensure that the pressing plate 63 can be pressed on the upper side of the fabric 9, so that the needle and thread can sew the overlock normally, and can ensure that excessive pressure is not applied to the fabric 9 to cause indentations; the design of the waist-shaped hole 611 can fine-tune the height of the presser foot 6 as needed, ensuring that the presser foot 6 can work normally without causing indentations on the upper side of the fabric 9.

[0052] like Figure 3 and Figure 5 As shown, at least two guide holes 24 are provided on the lower bracket 2, and guide rods 8 are inserted into the guide holes 24. Positioning holes 25 that can communicate with the guide holes 24 are provided on the front side wall and / or the rear side wall of the lower bracket 2. Positioning screws for fixing the guide rods 8 and the lower bracket 2 are provided in the positioning holes 25, and the lower end of the guide rod 8 is fixedly connected to the tugboat bracket 81. The guide rods 8 can be adjusted to fix the lower bracket 2 and the guide rods 8 in cooperation with the positioning screws, and the height of the lower bracket 2 can be fine-tuned as needed, thereby controlling the height of the lower feeding step wheel 21 protruding from the work surface, so that the feeding process of the cloth feeding mechanism is smoother and more stable.

[0053] When the cloth feeding mechanism of the overlock sewing machine is working, the driving motor arranged on the machine body drives the connecting rod 5 to swing forward and backward. When the connecting rod 5 swings forward, the upper feeding wheel 11 and the lower feeding wheel 21 are driven to rotate through the upper crank 3 and the lower crank 4, thereby driving the fabric 9 to move from front to back. When the connecting rod 5 swings backward, the upper crank 3 and the lower crank 4 are reset. At the same time, due to the setting of the upper one-way needle bearing 12 and the lower one-way needle bearing 22, the upper feeding wheel 11 and the lower feeding wheel 21 will not rotate in the opposite direction as the connecting rod 5 swings backward. The above actions are repeated to realize the movement of the fabric 9.

[0054] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope defined by the claims of the present invention.

Claims

1. A cloth feeding mechanism of an overlock sewing machine, comprising an upper bracket (1), a lower bracket (2), and an upper feeding wheel (11) and a lower feeding wheel (21) arranged in parallel, wherein a fabric (9) can pass through a gap between the upper feeding wheel (11) and the lower feeding wheel (21), and characterized in that: An upper rotating shaft (13) is rotatably mounted on the upper bracket (1), an upper stepping wheel (11) is sleeved on the upper rotating shaft (13), and the upper rotating shaft (13) and the upper stepping wheel (11) are connected via an upper one-way needle bearing (12); one end of the upper rotating shaft (13) extends out of the upper bracket (1) and is fixedly connected to the middle part of the upper crank (3), the upper end of the upper crank (3) is hinged to the front end of the connecting rod (5), and the lower end of the upper crank (3) is connected to the upper end of the lower crank (4); a lower rotating shaft (23) is rotatably mounted on the lower bracket (2), a lower stepping wheel (21) is sleeved on the lower rotating shaft (23), and the lower rotating shaft (23) and the lower stepping wheel (21) are connected via a lower one-way needle bearing (22); the lower crank (4) The lower end of the upper bracket (1) is fixedly connected to the fixing sleeve (101) of the lower rotating shaft (23) or the lower one-way needle bearing (22); the lower crank (4) is provided with an elongated hole (41), the length direction of the elongated hole (41) is parallel to the length direction of the lower crank (4); the lower end of the upper crank (3) is installed with a connecting piece (31), and the connecting piece (31) can slide back and forth along the elongated hole (41); the front side of the upper bracket (1) is fixedly connected to a presser foot (6); the upper end of the upper bracket (1) is fixedly connected to an adjusting rod (7), the adjusting rod (7) passes through the body of the hemming sewing machine and extends from the upper end of the body; the upper end of the adjusting rod (7) is threadedly connected to an adjusting nut (71), and the height of the upper bracket (1) can be adjusted by rotating the adjusting nut (71).

2. The cloth feeding mechanism of the overlock sewing machine according to claim 1, characterized in that: The upper stepping wheel (11) and the lower stepping wheel (21) can rotate in opposite directions.

3. The cloth feeding mechanism of the overlock sewing machine according to claim 2, characterized in that: The upper one-way needle roller bearing (12) and the lower one-way needle roller bearing (22) both comprise a fixed sleeve (101) and an outer ring (102); the fixed sleeve (101) is fixedly connected to the corresponding upper rotating shaft (13) or the lower rotating shaft (23); the fixed sleeve (101) and the outer ring (102) are rotatably connected in one direction; and the outer ring (102) is tightly connected to the corresponding upper stepping wheel (11) and the lower stepping wheel (21).

4. The cloth feeding mechanism of the overlock sewing machine according to claim 1, characterized in that: Small protrusions are evenly distributed on the outer circumferences of the upper stepping wheel (11) and the lower stepping wheel (21).

5. The cloth feeding mechanism of an overlock sewing machine according to claim 1, characterized in that: The connecting member (31) is a pin shaft, and the lower part of the upper crank (3) is provided with at least two pin holes along the length direction. The pin shaft can pass through the pin hole and the elongated hole (41) and reciprocate relative to the elongated hole (41).

6. A cloth feeding mechanism for an overlock sewing machine according to any one of claims 1 to 5, characterized in that: The presser foot (6) comprises a connecting plate (61), a foot handle (62) and a pressing plate (63); the two ends of the foot handle (62) are fixedly connected to the connecting plate (61) and the pressing plate (63) respectively; the connecting plate (61) is fixedly connected to the front side of the upper bracket (1); the pressing plate (63) can be pressed on the upper surface of the fabric (9); a needle hole (631) is provided on the pressing plate (63) for the needle and thread to pass through; the lower side of the pressing plate (63) is higher than the lower edge of the upper feeding wheel (11).

7. The cloth feeding mechanism of the overlock sewing machine according to claim 6, characterized in that: The left and right sides of the connecting plate (61) are both provided with waist-shaped holes (611), the length direction of the waist-shaped holes (611) is parallel to the vertical direction, the front side surface of the upper bracket (1) is provided with mounting holes (14) matching with the waist-shaped holes (611), and the connecting plate (61) and the upper bracket (1) are fixedly connected by fasteners.

8. A cloth feeding mechanism for an overlock sewing machine according to any one of claims 1 to 5, characterized in that: The lower bracket (2) is provided with at least two guide holes (24), guide rods (8) are inserted into the guide holes (24), and positioning holes (25) that can communicate with the guide holes (24) are provided on the front side wall and / or the rear side wall of the lower bracket (2), and positioning screws for fixing the guide rods (8) and the lower bracket (2) are provided in the positioning holes (25), and the lower end of the guide rod (8) is fixedly connected to the tugboat bracket (81).

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