Oil-less sewing machine

Abstract

The utility model relates to an oil -free transmission type sewing machine, this is intelligent sewing machine and include head and machine base, be equipped with left thread hook, right thread hook, lower shaft, material mechanism and thread take -up mechanism on the head, left thread hook and right thread hook set up in the head one side facing the user, the end of lower shaft is connected with the rotating shuttle, material mechanism is located the direct upper side of rotating shuttle, thread take -up mechanism carries out thread take -up action under the drive of self -contained drive source, be equipped with main drive motor and main shaft on the machine base, and main drive motor drives main shaft rotation makes material mechanism carry out material action, and main shaft rotates with lower shaft in the drive of synchronous belt transmission under the drive of synchronous belt transmission, and independent drive source and main drive motor all are connected with the controller signal of intelligent sewing machine. The main shaft of the oil -free transmission type sewing machine only drives lower shaft homodirectional rotation through synchronous belt transmission, is completely oil -free, compact structure, and is convenient for arrangement.

Description

Technical Field

[0001] This utility model relates to the field of sewing equipment technology, and in particular to an oil-free transmission sewing machine. Background Technology

[0002] In modern flatbed sewing machines, a vertical shaft is installed between the main shaft (also known as the main drive shaft) and the lower shaft (also known as the rotary hook drive shaft). A pair of bevel gears connects the main shaft to the vertical shaft, and the vertical shaft to the lower shaft, ensuring that the main shaft and lower shaft rotate in opposite directions and that the lower shaft rotates at twice the speed of the main shaft. During high-speed operation, the gear pairs between the main shaft and lower shaft experience significant friction, wear, and noise, generating considerable heat. A lubrication system is needed to continuously spray oil to lubricate and cool the gears during machine operation. Therefore, an oil pan and an oil pump are typically located near the lower shaft to store oil. However, modern flatbed sewing machines often lack adequate sealing, failing to completely prevent oil leakage during high-speed operation. Oil leaks reduce production efficiency and increase scrap rates.

[0003] Currently, an improved transmission structure for the main shaft and lower shaft has emerged. An intermediate shaft is located between the main shaft and lower shaft, with the main shaft and intermediate shaft connected by a 1:1 synchronous belt. The intermediate shaft and lower shaft are connected by a pair of helical gears in a 1:2 ratio, and the helical gear set is installed in a gearbox and lubricated with grease, thus achieving oil-free transmission between the main shaft and lower shaft. However, although this improved transmission structure reduces reliance on lubricating oil compared to traditional transmission structures, its three-axis transmission structure still suffers from problems such as complex overall structure, large space requirement, and inconvenient layout. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides an oil-free transmission sewing machine that is completely oil-free, compact in structure, and easy to arrange.

[0005] The present invention adopts the following technical solution:

[0006] This utility model provides an oil-free transmission sewing machine, which is an intelligent sewing machine and includes a sewing head and a base. The sewing head is equipped with a left thread hook, a right thread hook, a lower shaft, a thread-feeding mechanism, and a thread-taking mechanism. The left and right thread hooks are located on the side of the sewing head facing the user. A rotary hook is connected to the end of the lower shaft. The thread-feeding mechanism is located directly above the rotary hook. The thread-taking mechanism performs the thread-taking action under the drive of its own independent drive source. The base is equipped with a main drive motor and a main shaft. The main drive motor drives the main shaft to rotate, causing the thread-feeding mechanism to perform the thread-feeding action. The main shaft rotates in the same direction as the lower shaft under the drive of a synchronous belt. Both the independent drive source and the main drive motor are connected to the controller signal of the intelligent sewing machine.

[0007] Preferably, a driving pulley is provided on the main shaft and a driven pulley is provided on the lower shaft. The driving pulley and the driven pulley are connected by a toothed belt drive, and the tooth ratio of the driving pulley to the driven pulley is 2:1.

[0008] Preferably, the needle insertion mechanism includes a needle bar crank, a thread take-up crank, a needle bar connecting rod, a needle bar connecting post, a needle bar, and a needle. The needle bar crank is rotatably mounted on the main shaft. One end of the thread take-up crank is hinged to the needle bar crank, and the other end of the thread take-up crank is hinged to the head end of the needle bar connecting rod. The tail end of the needle bar connecting rod is hinged to the needle bar connecting post. The needle bar connecting post is vertically and vertically limited within the guide groove. The needle bar is snapped and fixed on the needle bar connecting post. The needle is located at the bottom of the needle bar and directly above the rotary hook.

[0009] Preferably, the thread-taking mechanism includes a thread-taking rod and a thread-taking drive motor. The machine head has a vertically opening slot on the side facing the user. One end of the thread-taking rod is located inside the machine head, and the other end of the thread-taking rod has a thread-passing hole and extends out of the opening slot. The thread-taking drive motor is located on the side of the machine head away from the machine base, and the drive shaft of the thread-taking drive motor passes through the machine head and is vertically connected to the thread-taking rod. The thread-taking drive motor drives the thread-taking rod to perform reciprocating swinging motion in the opening slot.

[0010] Preferably, the thread-carrying mechanism includes a thread-carrying rod and a thread-carrying drive motor. The thread-carrying rod is located on the side of the machine head facing the user, and the thread-carrying drive motor is located on the side of the machine head away from the user. The drive shaft of the thread-carrying drive motor extends out of the machine head and is perpendicularly connected to one end of the thread-carrying rod. The other end of the thread-carrying rod extends vertically to a thread-carrying column, which performs a complete circular motion under the drive of the thread-carrying drive motor.

[0011] Preferably, the thread take-up mechanism further includes a thread guide plate, which is located on the side of the machine head facing the user and between the machine head and the thread take-up lever. The thread guide plate is provided with a bushing for threading the thread.

[0012] Preferably, the thread-taking mechanism further includes a position adjustment component. Two guide rail grooves are symmetrically provided on the thread-taking reel. The center lines of the two guide rail grooves are perpendicular to the rotation axis of the thread-taking rod. Each guide rail groove is provided with a bushing. The position adjustment component is connected to the bushing and drives the bushing to move within the guide rail groove.

[0013] Preferably, the bushing is equipped with a sensing sensor, and both the position adjustment component and the sensing sensor are connected to the controller signal of the intelligent sewing machine.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] In actual use, the oil-free transmission sewing machine of this utility model drives the lower shaft to rotate in the same direction as the lower shaft of a traditional flat sewing machine via a synchronous belt drive. The feeding mechanism also performs feeding action under the drive of the main shaft. The thread take-up mechanism also maintains the timing coordination with the feeding mechanism and the thread taking-up mechanism under the rotation control of the independent drive source by the controller of the intelligent sewing machine, so as to perform normal sewing.

[0016] Obviously, compared with traditional flatbed sewing machines, the oil-free transmission sewing machine of this invention has a more compact transmission structure between the main shaft and the lower shaft, a lower space occupation rate, a longer service life, and a smoother transmission, which can reduce transmission noise under high-speed operation. In addition, since the synchronous belt drive does not require lubrication, the risk of oil leakage at this point can be avoided during machine use. At the same time, the oil pan, oil pump and other oil supply mechanisms at the bottom of the machine can be eliminated, which can effectively simplify the complexity of the overall machine structure, facilitate layout, and reduce the overall cost of the machine. Attached Figure Description

[0017] Figure 1 This is a diagram showing the supply and demand relationship of flatbed sewing machines in the current technology.

[0018] Figure 2 This is a structural diagram of an oil-free transmission sewing machine after removing the machine head and base, according to an embodiment of this utility model.

[0019] Figure 3 This is a structural diagram of the material feeding mechanism of an oil-free transmission sewing machine in an embodiment of this utility model.

[0020] Figure 4 This is an installation diagram of the first type of thread take-up mechanism on an oil-free transmission sewing machine according to an embodiment of this utility model.

[0021] Figure 5 This is a diagram showing the thread-carrying state of the first type of thread take-up mechanism on an oil-free transmission sewing machine, according to an embodiment of this utility model.

[0022] Figure 6 This is a schematic diagram illustrating the calculation of thread supply for the first type of thread take-up mechanism on an oil-free transmission sewing machine, as described in this embodiment of the present invention.

[0023] Figure 7 This is a first type of thread supply and demand diagram for the first type of thread take-up mechanism on an oil-free transmission sewing machine, as described in this utility model embodiment.

[0024] Figure 8 This is a second thread supply and demand diagram for the first thread take-up mechanism on an oil-free transmission sewing machine, as described in this embodiment of the utility model.

[0025] Figure 9 This is an installation diagram of the second type of thread take-up mechanism on an oil-free transmission sewing machine according to an embodiment of this utility model.

[0026] Figure 10 This is a diagram showing the thread-carrying state of the second type of thread take-up mechanism on an oil-free transmission sewing machine in this embodiment of the present invention.

[0027] The reference numerals in the attached figures are explained as follows:

[0028] 1. Machine head; 101. Opening slot; 2. Machine base; 3. Left hook; 4. Right hook; 5. Lower shaft; 6. Feeding mechanism; 601. Needle bar crank; 602. Thread take-up crank; 603. Needle bar connecting rod; 604. Needle bar connecting column; 605. Needle bar; 606. Needle; 607. Guide groove; 7. Thread take-up mechanism; 701. Thread take-up rod; 702. Thread take-up drive motor; 703. Thread take-up column; 704. Thread guide plate; 705. Bushing; 706. Guide rail groove; 707. Thread pass hole; 8. Rotary hook; 9. Main shaft; 10. Driving pulley; 11. Driven pulley; 12. Toothed belt. Detailed Implementation

[0029] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. These embodiments are only used to illustrate this utility model and are not intended to limit it.

[0030] In the description of this utility model, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They 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, and therefore should not be construed as a limitation on this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0032] Furthermore, in the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0033] See Figure 2 , Figure 4 and Figure 9 This embodiment provides an oil-free transmission sewing machine, which is an intelligent sewing machine and includes a sewing head 1 and a base 2. The sewing head 1 is equipped with a left thread hook 3, a right thread hook 4, a lower shaft 5, a thread-feeding mechanism 6, and a thread-taking mechanism 7. The left thread hook 3 and the right thread hook 4 are located on the side of the sewing head 1 facing the user. A rotary hook 8 is connected to the end of the lower shaft 5. The thread-feeding mechanism 6 is located directly above the rotary hook 8. The thread-taking mechanism 7 performs the thread-taking action under the drive of its own independent drive source. The base 2 is equipped with a main drive motor and a main shaft 9. The main drive motor drives the main shaft 9 to rotate, causing the thread-feeding mechanism 6 to perform the thread-feeding action. The main shaft 9 rotates in the same direction as the lower shaft 5 under the drive of the synchronous belt drive. Both the independent drive source and the main drive motor are connected to the controller signal of the intelligent sewing machine.

[0034] In actual use, the oilless transmission sewing machine of this embodiment drives the lower shaft 5 to rotate in the same direction as the lower shaft of a traditional flat sewing machine via a synchronous belt drive. The material feeding mechanism 6 also performs material feeding action under the drive of the main shaft 9. The thread take-up mechanism 7 also maintains the timing coordination with the material feeding mechanism and the thread feeding mechanism under the rotation control of the independent drive source by the controller of the intelligent sewing machine, so as to perform normal sewing.

[0035] Obviously, compared with traditional flatbed sewing machines, the transmission structure between the main shaft 9 and the lower shaft 5 in the oilless transmission sewing machine of this embodiment is more compact, has a lower space occupation rate, a longer service life, and a smoother transmission, which can reduce transmission noise under high-speed operation. In addition, since the synchronous belt drive does not require lubrication, the risk of oil leakage at this point can be avoided during machine use. At the same time, the oil pan, oil pump and other oil supply mechanisms at the bottom of the machine can be eliminated, which can effectively simplify the complexity of the overall machine structure, facilitate layout, and reduce the overall machine cost.

[0036] It should be noted that when the lower shaft 5 rotates in the same direction as the lower shaft of a traditional flatbed sewing machine, the main shaft 9 rotates in the opposite direction. This alters the timing coordination between the traditional thread take-up mechanism, the thread take-up mechanism, and the feeding mechanism, preventing the normal sewing function. Therefore, this oil-free transmission sewing machine is specifically equipped with a thread take-up mechanism 7 with an independent drive source to work in conjunction with the synchronous belt drive structure. The controller of the intelligent sewing machine can control the rotation of the main shaft 9 and the thread take-up action of the thread take-up mechanism 7 separately, ensuring proper timing coordination. Since the reverse rotation of the main shaft 9 does not affect the timing coordination between the thread take-up mechanism and other mechanisms, the thread take-up mechanism 6 is still driven by the main shaft 9 to perform the thread take-up action.

[0037] Preferably, see Figure 2The main shaft 9 is equipped with a drive pulley 10, and the lower shaft 5 is equipped with a driven pulley 11. The drive pulley 10 and the driven pulley 11 are connected by a toothed belt 12, and the tooth ratio of the drive pulley 10 to the driven pulley 11 is 2:1, that is, the transmission ratio of the drive pulley 10 to the driven pulley 11 is 1:2, so that the rotational speed of the lower shaft 5 is twice that of the main shaft 9, and the direction of rotation of the lower shaft 5 is the same as that of the main shaft 9.

[0038] Preferably, see Figure 3 The needle bar mechanism 6 includes a needle bar crank 601, a thread take-up crank 602, a needle bar connecting rod 603, a needle bar connecting post 604, a needle bar 605, and a needle 606. The needle bar crank 601 is rotatably mounted on the main shaft 9. One end of the thread take-up crank 602 is hinged to the needle bar crank 601, and the other end of the thread take-up crank 602 is hinged to the head end of the needle bar connecting rod 603. The tail end of the needle bar connecting rod 603 is hinged to the needle bar connecting post 604. The needle bar connecting post 604 is vertically and vertically limited within the guide groove 607. The needle bar 605 is snapped and fixed on the needle bar connecting post 604. The needle 606 is located at the bottom of the needle bar 605 and directly above the rotary hook 8. In actual use, the main shaft 9 rotates and drives the needle bar connecting rod 603 to pull the needle bar connecting column 604 up and down in the guide groove 607 through the needle bar crank 601 and the thread take-up crank 602, thereby driving the needle 606 together with the needle bar 605 to perform the material piercing action.

[0039] This embodiment of the oil-free drive sewing machine has two different specific implementation schemes for the thread take-up mechanism, which are described in detail below:

[0040] Example 1 of the thread-picking mechanism:

[0041] See Figure 4 and Figure 5 In this embodiment, the thread-taking mechanism 7 includes a thread-taking rod 701 and a thread-taking drive motor 702. The thread-taking rod 701 is located on the side of the machine head 1 facing the user, and the thread-taking drive motor 702 is located on the side of the machine head 1 away from the user. The drive shaft of the thread-taking drive motor 702 passes through the machine head 1 and is perpendicularly connected to one end of the thread-taking rod 701. The other end of the thread-taking rod 701 extends vertically to a thread-taking column 703. The thread-taking column 703 performs a complete circular motion under the drive of the thread-taking drive motor 702.

[0042] When using the thread-taking mechanism 7 of this embodiment to take the thread, the thread passes around the thread-taking post 703 on the thread-taking rod 701. In addition, in this embodiment, since the thread-taking rod 701 can make a complete circular motion in the same direction, there is no problem of sudden acceleration when the thread-taking rod 701 rotates to a critical position. The average load and heat generation of the thread-taking drive motor 702 are significantly less than those of the swing-type thread-taking mechanism.

[0043] Preferably, see Figure 5The thread-taking mechanism 7 also includes a thread guide plate 704, which is disposed on the side of the machine head 1 facing the user and located between the machine head 1 and the thread-taking lever 701. The thread guide plate 704 is provided with a bushing 705 for threading. When using the thread-taking mechanism 7 of this embodiment to take out the thread, the top thread passes through the bushing 705 on the thread guide plate 704.

[0044] Preferably, see Figure 5 The thread take-up mechanism 7 also includes a position adjustment component. Two guide rail grooves 706 are symmetrically arranged on the thread guide plate 704. The center lines of the two guide rail grooves 706 intersect perpendicularly with the rotation axis of the thread take-up lever 701. Each guide rail groove 706 contains a bushing 705. The position adjustment component is connected to the bushing 705 and drives the bushing 705 to move within the guide rail groove 706. In actual use, the thread take-up mechanism 7 of this embodiment can fix the two bushings 705 at appropriate positions on the guide rail grooves 706 according to the sewing conditions, thereby adapting to different sewing conditions.

[0045] Preferably, in this embodiment, the position adjustment component can be a linkage group driven by a rotary motor or a linear motor.

[0046] In this embodiment, see Figure 5 The thread-carrying mechanism 7 passes the thread as follows: the top thread first passes through the right hook 4, then through the bushing 705 near the right hook 4 to the side of the thread-carrying rod 701 of the thread-carrying disc 704, then passes under the thread-carrying column 703, then passes through the bushing 705 on the left hook 3 to the side of the head 1 of the thread-carrying disc 704, and finally passes through the left hook 3.

[0047] The existing supply and demand relationship of flatbed sewing machines is as follows: Figure 1 As shown, curve I represents the thread requirement for sewing thin fabrics with a small stitch pitch, curve II represents the thread requirement for sewing thick fabrics with a large stitch pitch, curve III represents the standard thread supply, and curve IV represents the thread supply after shifting the right hook to the left. Figure 1 It can be seen that curve III can form an envelope of curve I, and the supply and demand of line quantity are reasonably matched; however, curves II and III have obvious interference in regions a, b, and c, with insufficient line quantity, which can easily cause poor stitches or even line breakage. At this time, it is necessary to move the right hook to the left to fine-tune the line quantity to obtain curve IV. However, although the supply and demand line quantity matching in region b is significantly improved, moving the right hook to the left has little effect on regions a and c. This is because the "quasi-sine" shape of the supply and demand line quantity curve is determined by the structural form and lever length parameters of the four-bar linkage. Changing the position of the right hook alone can only fine-tune the peak value of the line quantity.

[0048] In this embodiment, the wire picking mechanism is driven independently by a newly added drive source. Therefore, the shape and size of the wire supply curve can be freely adjusted without affecting the shape and size of the wire demand curve. Thus, the wire supply can be adaptively adjusted according to the wire demand by changing the drive source control logic.

[0049] like Figure 7 and Figure 8 The diagram shows the supply and demand relationship of the two thread-taking mechanisms in this embodiment. It can be seen that... Figure 7 and Figure 8 Curves II and IV in the diagram have no interference in regions a, b, and c, ensuring sufficient thread supply, resulting in smoother and more aesthetically pleasing stitches, reduced thread tension, and a lower breakage rate. In this embodiment, when the take-up drive motor 702 controls the take-up lever 701 to rotate at a constant speed, the timing ratio of its thread feeding and take-up stages is 1:1. However, if the rotation speed of the take-up lever 701 during the thread feeding stage is reduced to half of that during constant speed movement, it can achieve... Figure 1 The standard line supply for curve III; if the line-taking drive motor 702 controls the line-taking lever 701 to rotate from the highest point to the lowest point, stop at the lowest point for a period of time, and then rotate back to the highest point, then the following can be achieved: Figure 7 The amount of wire supplied for curve IV; and so on, further modifications to the control logic of the wire-picking drive motor 702 can ultimately achieve the desired result. Figure 8 The amount of thread supplied to curve IV. Therefore, the thread take-up mechanism 7 in this embodiment can enhance sewing adaptability by changing the matching relationship between the supply and demand of thread by altering the drive source control logic.

[0050] Preferably, a sensing sensor is provided on the bushing 705, and both the position adjustment component and the sensing sensor are connected to the controller signal of the intelligent sewing machine.

[0051] See Figure 6 The principle for calculating the line supply of the circumferential rotating line-taking mechanism in this embodiment is as follows: During operation, the spatial position of the line-taking column 703 continuously changes, that is, the lengths of line segments ED and EF change, and the lengths of the two line segments are denoted as L. ED and L EF The sum of the two line segments is denoted as R. （φ） =L ED +L EF Where φ is the principal axis rotation angle, and R （φ） It varies with the value of φ. Within one working cycle, when point E is at its lowest point, R... （φ） It has a maximum value R （φ）max Maximum value R （φ）max Subtract the sum R of the line segments at a certain moment （φ） The excess thread can be used to form a loop and rotate around the rotary hook 8 to form a stitch, so this difference is the amount of thread supplied, denoted as ΔR. （φ） In other words, ΔR（φ） =R （φ）max -R （φ） .

[0052] Since the bushing 705 can be adjusted in relative position on the guide rail groove 706, the maximum value R of the sum of the line segments ED and EF at both ends is increased. （φ）max The changes are so that for certain special scenarios, such as when the fabric suddenly goes too far during sewing, or when the fabric thickness and stitch length suddenly increase, the height of the bushing 705 can be adjusted by feedback control from the sensing sensor to increase the amplitude of the thread supply curve in region b, thereby adapting to the over-stitching condition and reducing or avoiding the occurrence of skipped stitches, broken threads, etc.

[0053] Example 2 of the thread-picking mechanism:

[0054] See Figure 9 and Figure 10 In this embodiment, the thread-taking mechanism 7 includes a thread-taking rod 701 and a thread-taking drive motor 702. The machine head 1 has an opening slot 101 vertically on the side facing the user. One end of the thread-taking rod 701 is located inside the machine head 1, and the other end of the thread-taking rod 701 has a thread-passing hole 707 and extends out of the opening slot 101. The thread-taking drive motor 702 is located on the side of the machine head 1 away from the machine base 2, and the drive shaft of the thread-taking drive motor 702 passes through the machine head 1 and is vertically connected to the thread-taking rod 701. The thread-taking drive motor 702 drives the thread-taking rod 701 to perform reciprocating swinging motion in the opening slot 101.

[0055] In this embodiment, the thread guide mechanism 7 follows the same thread-passing method as a traditional flat sewing machine, see [link to documentation]. Figure 10 The thread first passes through the right hook 4, then through the thread hole 707 of the thread take-up rod 701, and finally through the left hook 3. During operation, the thread take-up drive motor 702 acts as the drive source, and works with the main shaft 9 to control the reciprocating swing motion of the thread take-up rod 701, thereby performing the thread take-up function.

[0056] Furthermore, since the thread take-up drive motor 702, as an independent drive source, is connected to the controller signal of the intelligent sewing machine, the controller of the intelligent sewing machine can achieve the following by controlling the rotation logic of the thread take-up drive motor 702 when the thread take-up lever 701 is performing the thread take-up and take-down movement: Figure 7 and Figure 8 The amount of thread supplied to curve IV is adjusted to achieve a better matching relationship between supply and demand, thereby improving the quality of the stitches. This will not be elaborated further here.

[0057] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. An oil-free transmission sewing machine, characterized in that, The oil-free transmission sewing machine is an intelligent sewing machine and includes a head (1) and a base (2). The head (1) is equipped with a left thread hook (3), a right thread hook (4), a lower shaft (5), a thread-feeding mechanism (6), and a thread-taking mechanism (7). The left thread hook (3) and the right thread hook (4) are located on the side of the head (1) facing the user. The end of the lower shaft (5) is connected to a rotary hook (8). The thread-feeding mechanism (6) is located directly above the rotary hook (8). The thread-taking mechanism (7) performs thread-taking action under the drive of its own independent drive source. The base (2) is equipped with a main drive motor and a main shaft (9). The main drive motor drives the main shaft (9) to rotate so that the thread-feeding mechanism (6) performs the thread-feeding action. The main shaft (9) rotates in the same direction as the lower shaft (5) under the drive of the synchronous belt drive. The independent drive source and the main drive motor are both connected to the controller signal of the intelligent sewing machine.

2. The oil-free transmission sewing machine according to claim 1, characterized in that, The main shaft (9) is provided with a drive pulley (10), and the lower shaft (5) is provided with a driven pulley (11). The drive pulley (10) and the driven pulley (11) are connected by a toothed belt (12), and the ratio of the number of teeth of the drive pulley (10) to the driven pulley (11) is 2:

1.

3. The oil-free transmission sewing machine according to claim 1, characterized in that, The needle insertion mechanism (6) includes a needle bar crank (601), a thread take-up crank (602), a needle bar connecting rod (603), a needle bar connecting post (604), a needle bar (605), and a needle (606). The needle bar crank (601) is rotatably mounted on the main shaft (9). One end of the thread take-up crank (602) is hinged to the needle bar crank (601), and the other end of the thread take-up crank (602) is hinged to the head end of the needle bar connecting rod (603). The tail end of the needle bar connecting rod (603) is hinged to the needle bar connecting post (604). The needle bar connecting post (604) is vertically and vertically limited within the guide groove (607). The needle bar (605) is snapped and fixed on the needle bar connecting post (604). The needle (606) is located at the bottom of the needle bar (605) and directly above the rotary hook (8).

4. The oil-free transmission sewing machine according to claim 1, characterized in that, The thread-taking mechanism (7) includes a thread-taking rod (701) and a thread-taking drive motor (702). The machine head (1) has an opening slot (101) on the side facing the user. One end of the thread-taking rod (701) is located inside the machine head (1), and the other end of the thread-taking rod (701) has a thread hole (707) and extends out of the opening slot (101). The thread-taking drive motor (702) is located on the side of the machine head (1) away from the machine base (2), and the drive shaft of the thread-taking drive motor (702) passes through the machine head (1) and is vertically connected to the thread-taking rod (701). The thread-taking drive motor (702) drives the thread-taking rod (701) to perform reciprocating swinging motion in the opening slot (101).

5. The oil-free transmission sewing machine according to claim 1, characterized in that, The thread-carrying mechanism (7) includes a thread-carrying rod (701) and a thread-carrying drive motor (702). The thread-carrying rod (701) is located on the side of the machine head (1) facing the user. The thread-carrying drive motor (702) is located on the side of the machine head (1) away from the user. The drive shaft of the thread-carrying drive motor (702) passes through the machine head (1) and is perpendicularly connected to one end of the thread-carrying rod (701). The other end of the thread-carrying rod (701) extends vertically to a thread-carrying column (703). The thread-carrying column (703) makes a complete circular motion under the drive of the thread-carrying drive motor (702).

6. The oil-free transmission sewing machine according to claim 5, characterized in that, The thread-taking mechanism (7) also includes a thread guide (704), which is located on the side of the machine head (1) facing the user and between the machine head (1) and the thread-taking rod (701). The thread guide (704) is provided with a bushing (705) for threading the thread.

7. The oil-free transmission sewing machine according to claim 6, characterized in that, The thread-taking mechanism (7) also includes a position adjustment component. Two guide rail grooves (706) are symmetrically provided on the thread guide plate (704). The center line of the two guide rail grooves (706) intersects perpendicularly with the rotation axis of the thread-taking rod (701). A bushing (705) is provided in each guide rail groove (706). The position adjustment component is connected to the bushing (705) and drives the bushing (705) to move in the guide rail groove (706).

8. The oil-free transmission sewing machine according to claim 7, characterized in that, The bushing (705) is equipped with a sensing sensor, and both the position adjustment component and the sensing sensor are connected to the controller signal of the intelligent sewing machine.

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