A mechanism and sewing machine driven by a single motor for reverse and forward sewing and presser foot lifting device

Abstract

The present invention belongs to the technical field of sewing equipment, and particularly refers to a mechanism and a sewing machine driven by a single motor for reverse and forward sewing and presser foot lifting; the driving motor is arranged on a sewing machine casing, the rotating shaft of the driving motor passes through a rotating shaft mounting hole and extends into the sewing machine casing, and the rotating shaft is connected to a swing seat through a driving mechanism; a driving cam is also arranged on the rotating shaft, the driving cam is connected to a driving rear lever through a driving rod, one end of the driving rear lever is hinged on the casing, and the other end is connected to one end of the rear lever, or the driving cam is connected to one end of the rear lever through a driving rod, and the middle part of the rear lever is rotatably connected to the sewing machine casing; when the rotating shaft of the driving motor continues to rotate to realize presser foot lifting after the forward or reverse sewing reaches the maximum stitch length; the present invention can realize reverse and forward sewing and automatic presser foot lifting through one motor, has a compact structure, reduces manufacturing costs, and is convenient for operators to install.

Description

Technical field:

[0001] The invention belongs to the technical field of sewing equipment, and in particular relates to a mechanism and a sewing machine driven by a single motor to drive a reverse and forward sewing and a presser foot lifting device. Background technology:

[0002] At present, the swing seat on the sewing machine is generally driven by the reverse stitching electromagnet, reverse stitching wrench and stitch length wheel on the mechanism. When the position of the swing seat needs to be adjusted, the stitch length must be adjusted first, and then the reverse stitching wrench or electromagnet drives the swing seat through the crank, connecting rod, etc., so as to finally adjust the stitch length. In order to improve the defects of manual reverse and forward stitching, automatic reverse and forward stitching conversion devices have appeared on the market. The automatic presser foot lifting device on the sewing machine has been well promoted. However, the driver for driving the automatic presser foot lifting and reverse and forward stitching switching is usually provided with two sets. For example, the Chinese invention patent application (publication number CN105821597 A, application date: 2016.05.23, application publication date 2016.08.03) discloses an automatic presser foot lifting and reverse and forward stitching device and a sewing machine of a sewing machine, including a presser foot lifting driver and a reverse and forward stitching driver, and the purpose of switching between reverse and forward stitching and automatic presser foot lifting is achieved respectively through two independent mechanisms, which has the defects of complex parts, large occupied space, and high manufacturing cost. Summary of the invention:

[0003] The object of the present invention is to provide a mechanism and a sewing machine with a single-motor driven reverse and forward sewing and presser foot lifting device which has a compact structure and reduces manufacturing costs.

[0004] The present invention is achieved in that:

[0005] One of the objects of the present invention is to provide a mechanism of a single-motor driven forward and reverse sewing and presser foot lifting device, comprising a sewing machine housing, a driving motor, and a swing seat, wherein the sewing machine housing is provided with a rotating shaft mounting hole, the driving motor is arranged on the sewing machine housing, the rotating shaft of the driving motor passes through the rotating shaft mounting hole and extends into the sewing machine housing, and the rotating shaft is connected to the swing seat through a driving mechanism; a driving cam is also provided on the rotating shaft, the driving cam is connected to a driving rear lever through a driving rod, one end of the driving rear lever is hinged on the housing, and the other end is connected to one end of the rear lever, and the middle part of the rear lever is rotatably connected to the sewing machine housing; or the driving cam is connected to one end of the rear lever through the driving rod, and the middle part of the rear lever is rotatably connected to the sewing machine housing; when the rotating shaft of the driving motor continues to rotate to realize presser foot lifting after the forward or reverse sewing reaches the maximum stitch length.

[0006] In the above-mentioned mechanism of a single-motor driven reverse sewing and presser foot lifting device, it also includes a limit frame connection, the limit frame is provided with a horizontal bending portion, the horizontal bending portion is provided with a through hole for the driving rod to pass through, the driving rod is provided with a limit ring, the lower end of the driving rod passes through the through hole and is connected with the driving cam, the limit ring is limited on the horizontal bending portion, and the limit frame is installed on the sewing machine casing.

[0007] In the above-mentioned mechanism of a single-motor driven reverse and forward stitching and presser foot lifting device, a buffer pad is arranged between the limiting ring and the horizontal bending part, and the driving rod is passed through the buffer pad.

[0008] In the above-mentioned mechanism of a single-motor driven reverse and forward stitching and presser foot lifting device, the driving rod is penetrated through the spring seat and the spring, the lower end of the spring is arranged on the spring seat, and the upper end is arranged on the buffer pad.

[0009] In the above-mentioned mechanism of a single-motor driven reverse and forward sewing and presser foot lifting device, the lower end of the driving rod passes through a through hole on a limiting frame and is connected to a driving cam, and the limiting frame is mounted on a sewing machine casing.

[0010] In the above-mentioned single-motor driven reverse and forward stitching and presser foot lifting device, the shaft mounting hole is a reverse stitching wrench shaft hole or is obtained based on the reverse stitching wrench shaft hole, and the shaft mounting hole and the shaft are sealed with oil by an oil sealing member.

[0011] In the above-mentioned single-motor driven reverse stitching and presser foot lifting device, the driving mechanism is an eccentric wheel assembly, including an eccentric wheel and a first connecting rod. The eccentric wheel is connected to the rotating shaft, one end of the first connecting rod is connected to the eccentric wheel, and the other end is connected to the swing seat.

[0012] In the above-mentioned mechanism of a single-motor driven reverse and forward stitching and presser foot lifting device, the eccentric wheel includes a large diameter portion and a small diameter portion which are coaxially arranged, and a first eccentric hole is arranged on the large diameter portion and the small diameter portion, and the axis of the first eccentric hole is arranged parallel to the axis of the large diameter portion and the small diameter portion, the rotating shaft of the driving motor is connected to the first eccentric hole, one end of the first connecting rod is mounted on the small diameter portion, and an eccentric cover is arranged on the outer end surface of the small diameter portion, and the eccentric cover is provided with a second eccentric hole for the rotating shaft of the driving motor to pass through, and the eccentric cover is fixed on the outer end surface of the small diameter portion to axially limit the first connecting rod, and the first eccentric hole and the second eccentric hole are coaxially arranged.

[0013] In the above-mentioned mechanism of a single-motor driven reverse and forward stitching and presser foot lifting device, when the eccentric wheel has the largest eccentricity and is set toward the rear window of the sewing machine housing, the lower end of the driving rod is connected to the driving cam from the front side of the driving cam, and the rotating shaft of the driving motor rotates counterclockwise to cause the machine to reverse stitch, and when the reverse stitch length is at the maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot; the lower end of the driving rod is connected to the driving cam from the rear side of the driving cam, and the rotating shaft of the driving motor rotates clockwise to cause the machine to reverse stitch, and when the reverse stitch length is at the maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot;

[0014] When the eccentric wheel is set with the maximum eccentricity facing away from the rear window of the sewing machine case, the lower end of the driving rod is connected to the driving cam from the front side of the driving cam, and the rotating shaft of the driving motor rotates counterclockwise, and the machine is in forward sewing. When the forward sewing stitch length is at a maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot; the lower end of the driving rod is connected to the driving cam from the rear side of the driving cam, and the rotating shaft of the driving motor rotates clockwise, and the machine is in reverse sewing. When the reverse sewing stitch length is at a maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot.

[0015] In the above-mentioned single-motor driven reverse stitching and presser foot lifting device, one end of the rear lever is provided with a strip opening groove, and the other end of the driving rear lever is provided with a pin shaft, which is slidably arranged in the strip opening groove on the rear lever.

[0016] In the above-mentioned single-motor driven reverse stitching and presser foot lifting device, the driving mechanism is a crank-connecting rod mechanism, including a crank and a second connecting rod, the crank is fixed on the rotating shaft of the driving motor, one end of the second connecting rod is connected to the crank, and the other end is connected to the swing seat.

[0017] In the above-mentioned mechanism of a single-motor driven reverse and forward sewing and presser foot lifting device, when the maximum eccentricity of the crank-connecting rod mechanism is set toward the rear window direction of the sewing machine housing, the lower end of the driving rod is connected to the driving cam from the front side of the driving cam, the rotating shaft of the driving motor rotates counterclockwise to cause the machine to reverse sew, and when the reverse stitch length is at the maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot; the lower end of the driving rod is connected to the driving cam from the rear side of the driving cam, the rotating shaft of the driving motor rotates clockwise to cause the machine to reverse sew, and when the reverse stitch length is at the maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot;

[0018] When the maximum eccentricity of the crank-connecting rod mechanism is set to face away from the rear window of the sewing machine casing, the lower end of the driving rod is connected to the driving cam from the front side of the driving cam, and the rotating shaft of the driving motor rotates counterclockwise, and the machine is in forward sewing. When the forward sewing stitch length is at a maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot; the lower end of the driving rod is connected to the driving cam from the rear side of the driving cam, and the rotating shaft of the driving motor rotates clockwise, and the machine is in reverse sewing. When the reverse sewing stitch length is at a maximum value, the rotating shaft of the driving motor continues to rotate to lift the presser foot.

[0019] Another object of the present invention is to provide a sewing machine comprising the above-mentioned single-motor driven reverse and forward sewing and presser foot lifting device.

[0020] The outstanding advantages of the present invention compared with the prior art are:

[0021] The invention can realize reverse and forward sewing and automatic presser foot lifting through a motor, has a compact structure, reduces manufacturing costs, and is convenient for operators to install. Description of the drawings:

[0022] Figure 1 is an exploded schematic diagram of the first embodiment without the limiting frame;

[0023] Figure 2 It is an exploded schematic diagram of the first embodiment having a limit frame but no spring;

[0024] Figure 3 is an exploded schematic diagram of the first embodiment with a limit frame and a spring;

[0025] Figure 4 is a front view of the first embodiment;

[0026] Figure 5 is a side view of the first embodiment;

[0027] Figure 6 is a front view of the second embodiment;

[0028] Figure 7 is a side view of the second embodiment;

[0029] Figure 8 is a front view of the third embodiment;

[0030] Fig. 9 is a side view of embodiment 3;

[0031] Fig.10 is a front view of the fourth embodiment;

[0032] Fig.11 is a side view of the fourth embodiment;

[0033] Fig.12 is a front view of the fifth embodiment;

[0034] Fig.13 is a side view of the fifth embodiment;

[0035] Fig.14 is an explosion diagram of Embodiment 6;

[0036] Fig.15 is a front view of the sixth embodiment;

[0037] Fig.16is a side view of embodiment 6;

[0038] Fig.17 is a front view of Embodiment 7;

[0039] Fig.18 is a side view of Embodiment 7;

[0040] Fig.19 is a front view of the eighth embodiment;

[0041] Fig. 20 It is a side view of the eighth embodiment.

[0042] In the figure: 1, sewing machine casing; 2, driving motor; 3, swing seat; 4, shaft mounting hole; 5, shaft; 6, first connecting rod; 7, large diameter portion; 8, small diameter portion; 9, first eccentric hole; 10, eccentric cover; 11, second eccentric hole; 12, retaining spring; 13, driving cam; 14, driving rod; 15, driving rear lever; 16, rear lever; 17, strip opening groove; 18, pin shaft; 19, skeleton oil seal; 20, limit frame; 21, through hole; 22, push rod; 23, axial screw; 24, rear window; 25, crank; 26, second connecting rod; 27, limit ring; 28, buffer pad; 29, spring seat, 30, spring. Specific implementation method:

[0043] The present invention will be further described below with specific embodiments.

[0044] Example 1: See Figure 1 —5:

[0045] A sewing machine reverse and forward sewing and presser foot lifting driving device comprises a sewing machine housing 1, a driving motor 2, and a swing seat 3. The driving motor 2 is a stepping motor or a servo motor, and the present embodiment preferably uses a stepping motor. The sewing machine housing 1 is provided with a rotating shaft mounting hole 4, the driving motor 2 is fixed to the sewing machine housing 1 by screws, the rotating shaft 5 of the driving motor 2 passes through the rotating shaft mounting hole 4 and extends into the inner cavity of the sewing machine housing 1, and the rotating shaft 5 is connected to the swing seat 3 through a driving mechanism, and the rotating shaft 5 of the driving motor 2 rotates clockwise or counterclockwise to drive the driving mechanism to drive the swing seat 3 to swing to achieve the purpose of reverse and forward sewing conversion.

[0046] The driving mechanism described in this embodiment is an eccentric wheel assembly, including an eccentric wheel and a first connecting rod 6, the eccentric wheel is connected to the rotating shaft 5, one end of the first connecting rod 6 is connected to the eccentric wheel, and the other end is connected to the swing seat 3; the eccentric wheel includes a large diameter portion 7 and a small diameter portion 8 arranged coaxially, and a first eccentric hole 9 is arranged on the large diameter portion 7 and the small diameter portion 8, the axis of the first eccentric hole 9 is arranged parallel to the axis of the large diameter portion 7 and the small diameter portion 8, and the rotating shaft 5 of the driving motor 2 is connected to the first eccentric hole 9; one end of the first connecting rod 6 is sleeved on the small diameter portion 8, and an eccentric cover 10 is arranged on the outer end surface of the small diameter portion 8, and the eccentric cover 10 is provided with a second eccentric hole 11 for the rotating shaft 5 of the driving motor 2 to pass through, the eccentric cover 10 is fixed on the outer end surface of the small diameter portion 8 to axially limit the first connecting rod 6, and the first eccentric hole 9 and the second eccentric hole 11 are arranged coaxially. The other end of the first connecting rod 6 is connected to a pin on the swing seat 3 and is limited by a retaining spring 12 .

[0047] The rotating shaft 5 of the present invention is also provided with a driving cam 13, which is fixed on the rotating shaft 5 by radially arranged screws. The driving cam 13 is connected to a driving rear lever 15 through a driving rod 14, one end of the driving rear lever 15 is hinged on the sewing machine housing 1 through an axial screw, and the other end is connected to one end of a rear lever 16, one end of the rear lever 16 is provided with a strip opening groove 17, and the other end of the driving rear lever 15 is provided with a pin 18, which is slidably arranged in the strip opening groove 17 on the rear lever 16. The middle part of the rear lever 16 is rotatably connected to the sewing machine housing 1, and the other end of the rear lever 16 is connected to the pull rod of the presser foot lifting mechanism. Since the presser foot lifting mechanism belongs to the prior art, it will not be described here.

[0048] The present invention integrates the conversion of reverse and forward sewing and the presser foot lifting driving device together, and realizes two actions by driving a driving motor 2, has a compact structure, and effectively reduces the manufacturing cost.

[0049] like Figure 2 As shown, in order to eliminate the idle stroke during the presser foot lifting process, the present embodiment further provides a limit frame 20, and a horizontal bending portion is provided on the limit frame 20, and a through hole 21 is provided on the horizontal bending portion for the lower end of the driving rod 14 to pass through, and a limit ring 27 is provided on the driving rod 14. The specific position of the limit ring 27 is set according to actual conditions, and the lower end of the driving rod 14 passes through the through hole 21 on the limit frame 20 and is connected to the driving cam 13, and the limit ring 27 is limited on the horizontal bending portion, and the limit frame 20 is installed on the sewing machine housing 1.

[0050] In order to reduce noise, a buffer pad 28 is further provided on the driving rod 14 in this embodiment. The buffer pad 28 is located between the limiting ring 27 and the horizontal bending portion.

[0051] In order to increase the buffer, a spring may be further added to the present embodiment, and the structure is as follows: a spring seat 29 and a spring 30 are passed through the driving rod, the lower end of the spring 30 is arranged on the spring seat 29 , and the upper end is arranged on the buffer pad 28 .

[0052] The shaft mounting hole 4 of the present invention is a reverse-sewing spanner shaft hole or is obtained based on the reverse-sewing spanner shaft hole, which is obtained based on the reverse-sewing spanner shaft hole, such as by expanding the hole or processing it into a stepped hole. The improvement to the sewing machine housing 1 is small, and it is suitable for mass promotion and application. The shaft mounting hole 4 and the shaft 5 are sealed with oil by an oil sealing member, and the preferred oil sealing member in this embodiment is a skeleton oil seal 19.

[0053] The eccentric wheel with the largest eccentricity in this embodiment is arranged toward the rear window 24, and the lower end of the driving rod 14 is connected to the driving cam 13 from the front side of the driving cam 13. The front side here refers to the Figure 1 As a reference, the direction where the driving motor 2 is located is the left, the direction where the driving cam 13 is located is the right, the lower end of the driving rod 14 is in the front when it blocks the driving cam 13, and is in the rear when it does not block the driving cam 13, which is only for the convenience of description, and is not used to limit the scope of the present invention. When the rotating shaft 5 of the driving motor 2 rotates counterclockwise to the maximum value of the reverse stitch length, the rotating shaft 5 of the driving motor 2 continues to rotate, driving the driving rod 14 to pull down the driving rear lever 15, so that the driving rear lever 15 rotates downward around the hinge of the sewing machine housing 1, and the pin 18 slides outward in the strip opening groove 17 in the rear lever 16, driving the rear lever 16 to rotate around the middle so that the other end is lifted upward, and then pulling the pull rod of the presser foot lifting mechanism to realize the presser foot lifting action.

[0054] In order to retain the function of manually controlling the presser foot to lift, a push rod 22 is connected to the rear lever 16 .

[0055] The installation steps of this embodiment are as follows:

[0056] First, insert the first connecting rod 6 into the corresponding position of the eccentric wheel, install the eccentric cover 10 on the end surface of the small diameter part 8 of the eccentric wheel, and lock it with screws.

[0057] Knock the skeleton oil seal 19 into the shaft mounting hole 4 of the sewing machine casing 1, insert the shaft 5 of the driving motor 2 into the sewing machine casing 1 through the skeleton oil seal 19, and sequentially insert the eccentric wheel and the driving cam 13 on the shaft 5 from the inner cavity of the sewing machine casing 1 to the corresponding positions. At the same time, insert the small end of the first connecting rod 6 into the corresponding pin of the swing seat 3, and insert the retaining ring 12 into the corresponding retaining ring groove of the swing seat 3.

[0058] Insert the push rod 22 into the corresponding hole of the rear lever 16, fix the rear lever 16 to the corresponding position on the sewing machine housing 1 with the axial screw, and replace the original rear lever assembly of the machine at the same time.

[0059] Insert the driving rod 14 and the cylindrical pin into the corresponding position holes of the driving rear lever 15 in sequence and lock the cylindrical pin with a nut, and fix the driving rear lever 15 to the corresponding position of the sewing machine housing 1 with the axial screw 23.

[0060] Insert the limit ring 27 and the limit frame 20 into the driving rod 14 in sequence, or insert the limit ring 27, the limit frame 20, the spring 30, and the spring seat 29 into the driving rod 14 in sequence, and fix the limit frame 20 in the corresponding position of the sewing machine housing 1 with screws. Adjust the position of the rear lever 16 to eliminate the gap stroke and then lock the limit ring 27 against the limit frame 20.

[0061] Power on the drive motor 2 to find the motor zero position, find the mechanical zero position by adjusting the eccentric wheel assembly and lock it with a screw, run the machine to the maximum backstitch stitch length state, adjust the drive cam 13 to the corresponding position and lock it with a screw. At this point, the assembly process is basically completed.

[0062] The purpose of controlling the reverse and forward seams is achieved by controlling the eccentric wheel assembly to rotate counterclockwise or clockwise through the control system to control the swing seat to swing.

[0063] When the presser foot needs to be lifted, the drive motor 2 can be controlled to rotate counterclockwise to the maximum backstitch stitch length and then continue to rotate through the drive cam 13, the drive rod 14, and the drive rear lever 15 to drive the rear lever 16 to swing, thereby achieving the purpose of lifting the presser foot.

[0064] Example 2: See Figure 6-7 :

[0065] The structure of this embodiment is basically the same as that of the first embodiment, and the difference is that the lower end of the driving rod 14 of this embodiment is connected to the driving cam from the rear side of the driving cam 13. The rotating shaft 5 of the driving motor 2 rotates clockwise for reverse sewing, and the presser foot is lifted when the rotating shaft 5 of the driving motor 2 continues to rotate when the reverse sewing stitch length is at the maximum value to achieve the purpose of lifting the presser foot.

[0066] Example 3: See Figure 8-9 :

[0067] The eccentric wheel with the largest eccentricity end of this embodiment is arranged toward the inside of the sewing machine housing 1, which is, as the name implies, the reverse installation method with the eccentric wheel with the largest eccentricity end arranged toward the rear window 24. Therefore, the basic structure of this embodiment is the same as that of the first embodiment, and the difference lies in the installation direction of the eccentric wheel with the largest eccentricity end. In this embodiment, the lower end of the driving rod 14 is connected to the driving cam 13 from the front side of the driving cam 13. At this time, the driving motor 2 rotates counterclockwise to achieve the purpose of lifting the presser foot when the machine is in the normal sewing state. When the normal sewing stitch length is at the maximum value, the rotating shaft 5 of the driving motor 2 continues to rotate to achieve the purpose of lifting the presser foot.

[0068] Example 4: See Figure 10-11 :

[0069] The basic structure of this embodiment is the same as that of the third embodiment, except that the lower end of the driving rod 14 is connected to the driving cam 13 from the rear side of the driving cam 13. The rotating shaft 5 of the driving motor 2 rotates clockwise to perform reverse stitching, and the presser foot is lifted when the rotating shaft 5 of the driving motor 2 continues to rotate when the reverse stitch length is at the maximum value to achieve the purpose of lifting the presser foot.

[0070] Example 5: See Figure 12-13 :

[0071] The structure of this embodiment is basically the same as that of the first embodiment, except that the driving rod 14 of this embodiment is directly connected to the rear lever 16. The specific structure is as follows:

[0072] The lower end of the driving rod 14 is connected to the driving cam 13 , and the upper end is connected to one end of a rear lever 16 . The middle part of the rear lever 16 is rotatably connected to the sewing machine housing 1 .

[0073] The structure of this embodiment also includes the structure of Embodiments 1 to 4 that the presser foot can be lifted by clockwise or counterclockwise rotation. When the presser foot is lifted, the driving cam 13 rotates with the rotating shaft 5 of the driving motor 2, driving the driving rod 14 to move downward, thereby driving one end of the rear lever 16 to rotate downward and the other end to rotate upward to pull the pull rod of the presser foot lifting mechanism to lift the presser foot.

[0074] Example 6: See Figure 14-16 :

[0075] The structure of this embodiment is basically the same as that of the first embodiment, except that:

[0076] The driving mechanism of this embodiment is a crank-connecting rod mechanism, including a crank 25 and a second connecting rod 26 . The crank 25 is fixed on the rotating shaft 5 of the driving motor 2 . One end of the second connecting rod 26 is connected to the crank 25 , and the other end is connected to the swing seat 3 .

[0077] In this embodiment, the lower end of the driving rod 14 is connected to the driving cam 13 from the rear side of the driving cam 13. The rotating shaft 5 of the driving motor 2 rotates clockwise for reverse stitching, and the presser foot is lifted when the rotating shaft of the driving motor continues to rotate when the reverse stitch length is the maximum to achieve the purpose of lifting the presser foot.

[0078] Example 7: See Figure 17-18 :

[0079] This embodiment is substantially the same as the sixth embodiment, except that in this embodiment, the lower end of the driving rod 14 is connected to the driving cam 13 from the front side of the driving cam 13 .

[0080] The rotating shaft 5 of the driving motor 2 rotates counterclockwise for the machine to perform normal sewing. When the presser foot is lifted, the rotating shaft of the driving motor 2 continues to rotate when the normal sewing stitch length is at the maximum value to achieve the purpose of lifting the presser foot.

[0081] Example 8: See Figure 19-20 :

[0082] The structure of this embodiment is basically the same as that of the sixth embodiment, except that the lower end of the driving rod 14 of this embodiment is connected to the driving cam 13, and the upper end is connected to one end of the rear lever 16, and the middle part of the rear lever 16 is rotatably connected to the sewing machine housing 1.

[0083] In this embodiment, the lower end of the driving rod 14 is connected to the driving cam 13 from the front side of the driving cam 13. At this time, the rotating shaft 5 of the driving motor 2 rotates counterclockwise for the machine to be sewn, and when the presser foot is lifted, the rotating shaft of the driving motor 2 continues to rotate when the stitch length of the sewing is at the maximum value to achieve the purpose of lifting the presser foot.

[0084] Another object of the present invention is to provide a sewing machine, comprising the above-mentioned automatic reverse sewing and presser foot lifting device for the sewing machine.

[0085] The terms such as "front", "back", "first", "second", etc. cited in this specification are only for the convenience of description and are not intended to limit the scope of implementation of the present invention. Changes or adjustments to their relative relationships should be regarded as within the scope of implementation of the present invention without substantially changing the technical content.

[0086] The above embodiment is only one of the preferred embodiments of the present invention, and is not intended to limit the scope of implementation of the present invention. Therefore, any equivalent changes made based on the shape, structure, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A mechanism for a single motor driven reverse sewing and presser foot lifting device, characterized in that: The sewing machine comprises a sewing machine housing (1), a driving motor (2), and a swing seat (3); the sewing machine housing (1) is provided with a rotating shaft mounting hole (4); the driving motor (2) is arranged on the sewing machine housing (1); a rotating shaft (5) of the driving motor (2) passes through the rotating shaft mounting hole (4) and extends into the sewing machine housing (1); and the rotating shaft (5) is connected to the swing seat (3) via a driving mechanism; a driving cam (13) is also provided on the rotating shaft (5); the driving cam (13) is connected to a driving rear lever (15) via a driving rod (14); One end of the driving rear lever (15) is hinged on the sewing machine housing (1), and the other end is connected to one end of the rear lever (16), and the middle part of the rear lever (16) is rotatably connected to the sewing machine housing (1); or the driving cam (13) is connected to one end of the rear lever (16) through the driving rod (14), and the middle part of the rear lever (16) is rotatably connected to the sewing machine housing (1); when the rotating shaft (5) of the driving motor (2) continues to rotate after the forward sewing or reverse sewing reaches the maximum stitch length, the rotating shaft (5) of the driving motor (2) is lifted. It also includes a limit frame (20), the limit frame (20) is provided with a horizontal bending portion, the horizontal bending portion is provided with a through hole (21) for the driving rod (14) to pass through, the driving rod (14) is provided with a limit ring (27), the lower end of the driving rod (14) passes through the through hole (21) and is connected to the driving cam (13), the limit ring (27) is limited on the horizontal bending portion, the limit frame (20) is installed on the sewing machine housing (1), the position of the rear lever (16) is adjusted to eliminate the gap stroke, and then the limit ring (27) is locked against the limit frame (20); The rear lever (16) is connected to a push rod (22).

2. The mechanism of the single-motor driven reverse and forward sewing and presser foot lifting device according to claim 1, characterized in that: A buffer pad (28) is provided between the limiting ring (27) and the horizontal bending portion, and the driving rod (14) is passed through the buffer pad (28).

3. The mechanism of the single-motor driven reverse and forward sewing and presser foot lifting device according to claim 2, characterized in that: The driving rod (14) is inserted into the spring seat (29) and the spring (30); the lower end of the spring (30) is arranged on the spring seat (29) and the upper end is arranged on the buffer pad (28).

4. A mechanism for a single-motor driven reverse and forward sewing and presser foot lifting device according to any one of claims 1 to 3, characterized in that: The rotating shaft mounting hole (4) is a reverse-seam spanner shaft hole or is obtained based on a reverse-seam spanner shaft hole, and oil is sealed between the rotating shaft mounting hole (4) and the rotating shaft (5) via an oil sealing member.

5. A mechanism for a single-motor driven reverse and forward sewing and presser foot lifting device according to any one of claims 1 to 3, characterized in that: The driving mechanism is an eccentric wheel assembly, comprising an eccentric wheel and a first connecting rod (6), wherein the eccentric wheel is connected to the rotating shaft (5), one end of the first connecting rod (6) is connected to the eccentric wheel, and the other end is connected to the swing seat (3).

6. The mechanism of the single-motor driven reverse and forward sewing and presser foot lifting device according to claim 5, characterized in that: The eccentric wheel comprises a large diameter portion (7) and a small diameter portion (8) which are coaxially arranged. A first eccentric hole (9) is arranged on the large diameter portion (7) and the small diameter portion (8). The axis of the first eccentric hole (9) is arranged parallel to the axis of the large diameter portion (7) and the small diameter portion (8). The rotating shaft (5) of the driving motor (2) is connected to the first eccentric hole (9). One end of the first connecting rod (6) is sleeved on the small diameter portion (8). An eccentric cover (10) is arranged on the outer end surface of the small diameter portion (8). The eccentric cover (10) is provided with a second eccentric hole (11) for the rotating shaft (5) of the driving motor (2) to pass through. The eccentric cover (10) is fixedly arranged on the outer end surface of the small diameter portion (8) to axially limit the first connecting rod (6). The first eccentric hole (9) and the second eccentric hole (11) are coaxially arranged.

7. The mechanism of the single-motor driven reverse and forward sewing and presser foot lifting device according to claim 6, characterized in that: When the eccentric wheel is set toward the rear window (24) of the sewing machine housing (1) at the maximum eccentricity, the lower end of the driving rod (14) is connected to the driving cam (13) from the front side of the driving cam (13), the rotating shaft (5) of the driving motor (2) rotates counterclockwise to cause the machine to perform reverse stitching, and when the reverse stitching stitch length is at the maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot; the lower end of the driving rod (14) is connected to the driving cam (13) from the rear side of the driving cam (13), the rotating shaft (5) of the driving motor (2) rotates clockwise to cause the machine to perform reverse stitching, and when the reverse stitching stitch length is at the maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot; When the eccentric wheel is set to face away from the rear window of the sewing machine housing (1) at the maximum eccentricity, the lower end of the driving rod (14) is connected to the driving cam (13) from the front side of the driving cam (13), and the rotating shaft (5) of the driving motor (2) rotates counterclockwise to perform forward sewing. When the forward sewing stitch length is at a maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot; the lower end of the driving rod (14) is connected to the driving cam (13) from the rear side of the driving cam (13), and the rotating shaft (5) of the driving motor (2) rotates clockwise to perform reverse sewing. When the reverse sewing stitch length is at a maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot.

8. A mechanism for a single-motor driven reverse and forward sewing and presser foot lifting device according to any one of claims 1 to 3, characterized in that: One end of the rear lever (16) is provided with a strip-shaped opening groove (17), and the other end of the driving rear lever (15) is provided with a pin shaft (18), and the pin shaft (18) is slidably arranged in the strip-shaped opening groove (17) on the rear lever (16).

9. A mechanism for a single-motor driven reverse and forward sewing and presser foot lifting device according to any one of claims 1 to 3, characterized in that: The driving mechanism is a crank-connecting rod mechanism, comprising a crank (25) and a second connecting rod (26); the crank (25) is fixedly mounted on a rotating shaft (5) of a driving motor (2); one end of the second connecting rod (26) is connected to the crank (25) and the other end is connected to a swing seat (3).

10. The mechanism of the single-motor driven reverse and forward sewing and presser foot lifting device according to claim 9, characterized in that: When the maximum eccentricity of the crank-connecting rod mechanism is set toward the rear window direction of the sewing machine housing (1), the lower end of the driving rod (14) is connected to the driving cam (13) from the front side of the driving cam (13), the rotating shaft (5) of the driving motor (2) rotates counterclockwise to cause the machine to perform reverse stitching, and when the reverse stitching stitch length is at a maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot; the lower end of the driving rod (14) is connected to the driving cam (13) from the rear side of the driving cam (13), the rotating shaft (5) of the driving motor (2) rotates clockwise to cause the machine to perform reverse stitching, and when the reverse stitching stitch length is at a maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot; When the maximum eccentricity of the crank-connecting rod mechanism is set away from the rear window direction of the sewing machine housing (1), the lower end of the driving rod (14) is connected to the driving cam (13) from the front side of the driving cam (13), and the rotating shaft (5) of the driving motor (2) rotates counterclockwise to achieve forward sewing. When the forward sewing stitch length is at a maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot; the lower end of the driving rod (14) is connected to the driving cam (13) from the rear side of the driving cam (13), and the rotating shaft (5) of the driving motor (2) rotates clockwise to achieve reverse sewing. When the reverse sewing stitch length is at a maximum value, the rotating shaft (5) of the driving motor (2) continues to rotate to lift the presser foot.

11. A sewing machine, characterized in that: A mechanism comprising a single-motor driven reverse stitching and presser foot lifting device as described in any one of claims 1-10.

Images