CN213978120U - Mechanism for driving reverse and forward sewing, presser foot lifting and thread trimming device by single motor and sewing machine - Google Patents

Abstract

The utility model provides a single motor drive is down in the same direction as seam, is lifted presser foot and trimming device's mechanism and sewing machine belongs to sewing equipment technical field. The double-direction seam changing mechanism solves the technical problems that an existing driving mechanism for changing the reverse and forward seams, trimming the threads and lifting the presser foot is multiple in parts, large in structure and the like. The sewing machine comprises a machine shell, a swinging seat arranged in the machine shell and used for reversing seam conversion and adjusting needle pitch, a cutter shaft used for driving thread cutting action and a rear lever used for driving a presser foot to lift, the mechanism comprises a driving motor fixedly arranged on the machine shell, an output shaft of the driving motor extends into the machine shell, and a first driving component connected with the swinging seat and capable of driving the swinging seat, a second driving component connected with the rear lever and capable of driving the swinging seat and a third driving component connected with the cutter shaft and capable of driving the cutter shaft to rotate are arranged on the output shaft of the driving motor at intervals. The mechanism can drive three actions through one driving motor, and has the advantages of few parts and compact structure.

Description

Mechanism for driving reverse and forward sewing, presser foot lifting and thread trimming device by single motor and sewing machine

Technical Field

The utility model belongs to the technical field of sewing machine, a actuating mechanism among sewing machine is related to, especially single motor drive is down in the same direction as seam, is lifted presser foot and trimming device's mechanism and sewing machine.

Background

A sewing machine is a machine that uses one or more sewing threads to form one or more stitches in a material to be sewn, thereby interweaving or stitching one or more layers of material. The sewing machine can sew fabrics such as cotton, hemp, silk, wool, artificial fiber and the like and products such as leather, plastic, paper and the like, and the sewed stitches are neat, beautiful, flat and firm, the sewing speed is high, and the use is simple and convenient. The existing sewing machine is also provided with an automatic presser foot lifting structure, a stitch length adjusting structure, a backstitch structure and an automatic thread trimming structure, and the stitch length adjusting structure and the backstitch structure are combined together to have the functions of backstitch, seam thickening and the like. The traditional sewing machine has the defects of high noise, low precision and the like because the needle pitch adjustment and the backstitch driving are independently driven by an electromagnet; and the automatic presser foot lifting structure and the automatic thread trimming structure also need to be provided with a separate driving source for driving, so that the whole sewing machine is overstaffed in structure and large in occupied space.

For example, Chinese patent discloses (publication number: CN 109518363A; published: 2019-03-26) a backstitch and needle pitch adjusting structure of a sewing machine, which comprises a backstitch component and a needle pitch adjusting component, wherein the backstitch component comprises a backstitch crank which is arranged in a rotating way and a driving component which drives the backstitch crank to swing; the needle pitch adjusting assembly comprises a needle pitch adjusting piece, a connecting rod assembly and a swinging seat which is rotatably arranged and connected with the feeding shaft, one end of the connecting rod assembly is hinged with the needle pitch adjusting piece, the other end of the connecting rod assembly is hinged with the swinging seat, and the connecting rod assembly is connected with the backstitch crank in a sliding manner; the needle pitch adjusting piece is arranged on the machine shell and can be adjusted in length extending into the machine shell.

For example, the Chinese patent application (publication No. CN105821597A, published as 2016-08-03) discloses an automatic presser foot lifting and reversing sewing device of a sewing machine and the sewing machine, which comprises a presser foot lifting driver and a reversing sewing driver, and the purposes of reversing sewing switching and automatic presser foot lifting are respectively realized by two independent mechanisms.

These driving methods have the defects of complicated parts, large occupied space, high manufacturing cost and the like.

Disclosure of Invention

The utility model discloses to the above-mentioned problem that prior art exists, provide single motor drive in the same direction as seam, lift presser foot and trimming device's mechanism and sewing machine, the utility model aims to solve the technical problem that: how to provide a mechanism for changing back and forth sewing, trimming and lifting presser foot in a sewing machine with compact structure and wide application range.

The purpose of the utility model can be realized by the following technical proposal:

the sewing machine comprises a machine shell, a swinging seat arranged in the machine shell and used for reversing sewing conversion and needle pitch adjustment, a cutter shaft used for driving thread trimming action and a rear lever used for driving the presser foot to lift.

The working principle is as follows: the swinging seat can swing around the mounting pin, and the needle pitch adjusting structure and the backstitch structure are connected with the swinging seat, and the structures are in the prior art and are not described in detail herein. The size of the needle pitch is adjusted by changing the position angle of the swinging seat; or when the swinging seat swings to a preset angle, the state change between the reverse sewing and the forward sewing is completed. In the technical scheme, the driving motor is fixedly arranged on the shell of the sewing machine, and the swinging seat is driven to swing by the driving assembly I so as to achieve the purpose of reverse and forward sewing conversion; after the maximum stitch length of the forward sewing or the backward sewing, the driving motor continues to rotate and drives the rear lever to swing through the driving cam so as to achieve the purpose of lifting the presser foot, and just opposite to the purpose of lifting the presser foot, after the maximum stitch length of the backward sewing or the forward sewing, the driving motor continues to rotate and drives the cutter shaft through the bevel gear, and then the cutter shaft drives the cutter rest to swing so as to achieve the purpose of trimming. The utility model can realize the functions of reverse and forward seam switching, automatic presser foot lifting and automatic thread trimming through one motor, has compact structure and low manufacturing cost and use cost, and is convenient for operators to install, operate and use; the cost is effectively reduced, and the use effect of the sewing machine is improved.

In the mechanism of the single-motor driven backward and forward sewing, presser foot lifting and thread trimming device, the casing is provided with a mounting hole, the driving motor is arranged outside the casing and is fixedly connected to the casing through a fixing bolt, and an output shaft of the driving motor penetrates through the mounting hole and extends into the casing. The mounting hole is obtained for the backstitch wrench shaft hole or based on the backstitch wrench shaft hole, and oil is sealed between the mounting hole and the output shaft of the driving motor through an oil seal piece. Furthermore, one end face of the driving motor, which is provided with an output shaft, is attached to the end face of the shell, and the sealing element is arranged between the end face of the driving motor and the end face of the shell; the shell of the driving motor is fixedly connected with the shell through four fixing bolts; the end of the shell of the driving motor is provided with the mounting boss, and the four fixing bolts are distributed at four corners of the mounting boss, so that the whole structure is more compact, and the sealing performance is good.

In the mechanism for driving the backward and forward sewing, the presser foot lifting and the thread trimming device by the single motor, the driving component II comprises a driving cam fixedly arranged on an output shaft of the driving motor, and the driving component III comprises a bevel gear I fixedly arranged on the output shaft of the driving motor.

In the mechanism for driving the backward and forward sewing, the presser foot lifting and the thread trimming device by the single motor, the driving assembly comprises an eccentric connecting rod and an eccentric wheel fixedly arranged on an output shaft of the driving motor, one end of the eccentric connecting rod is sleeved on the eccentric wheel, and the other end of the eccentric connecting rod is hinged with one side of the swinging seat.

In the mechanism of the single motor driven backward and forward sewing, presser foot lifting and thread trimming device, the eccentric wheel comprises a large diameter part and a small diameter part which are coaxially arranged, first eccentric holes are arranged on the large diameter part and the small diameter part, the axes of the first eccentric holes are parallel to the axes of the large diameter part and the small diameter part, and the output shaft of the driving motor penetrates through the first eccentric holes; one end of the eccentric connecting rod is sleeved on the small-diameter portion and an eccentric cover is arranged on the outer end face of the small-diameter portion, a second eccentric hole for the output shaft of the driving motor to penetrate through is formed in the eccentric cover, the eccentric cover is fixedly arranged on the outer end face of the small-diameter portion and carries out axial limiting on the eccentric connecting rod, and the first eccentric hole and the second eccentric hole are coaxially arranged.

In the mechanism of the single-motor driven backward and forward sewing, presser foot lifting and thread trimming device, a first vertical shaft sleeve and a second horizontal shaft sleeve are arranged on the machine shell, a vertical shaft is rotatably inserted in the first shaft sleeve, a second bevel gear and a third bevel gear are fixedly arranged at the upper end and the lower end of the vertical shaft respectively, and the second bevel gear is meshed with the first bevel gear; the cutter shaft is rotatably inserted in the second shaft sleeve, one end of the cutter shaft is fixedly provided with a tight ring, the other end of the cutter shaft is fixedly provided with a fourth bevel gear, and the fourth bevel gear is engaged with the bevel gear in three phases.

In the mechanism of the single-motor driven backward and forward sewing, presser foot lifting and trimming device, a driving transmission rod is arranged on the machine shell, one end of the driving transmission rod is hinged on the machine shell, the driving cam is connected with the middle part of the driving transmission rod through a driving rod, and a pin shaft is arranged at the other end of the driving transmission rod; the middle part of the rear lever is rotatably connected to the shell, a strip-shaped open slot is formed in one end of the rear lever, and the pin shaft is embedded in the strip-shaped open slot in a sliding mode.

In the mechanism of the single-motor driven backward and forward sewing, presser foot lifting and thread trimming device, as a second scheme that the driving cam is connected with the rear lever, the middle part of the rear lever is rotatably connected on the machine shell, the driving cam is provided with a vertical driving rod, and the upper end of the driving rod is hinged with one end of the rear lever.

In the mechanism of the single-motor-driven backward and forward sewing, presser foot lifting and trimming device, the casing is further fixedly provided with a limiting frame, a horizontal bending part is arranged on the limiting frame, a through hole for the driving rod to pass through is formed in the horizontal bending part, a limiting tight ring is arranged on the driving rod, the lower end of the driving rod penetrates through the through hole to be connected with the driving cam, the limiting tight ring is limited on the horizontal bending part, and a cushion pad is arranged between the limiting tight ring and the horizontal bending part.

In the above-mentioned mechanism of the single motor driven backward and forward sewing, presser foot lifting and thread trimming device, when the maximum eccentric amount of the eccentric wheel is set toward the rear window direction of the housing: the lower end of the driving rod is connected with the driving cam from the front side of the driving cam, the output shaft of the driving motor rotates anticlockwise to lift the presser foot, when the backstitch needle pitch is maximum, the output shaft of the driving motor rotates clockwise to lift the presser foot, the output shaft of the driving motor rotates clockwise to cut threads, and when the backstitch needle pitch is maximum, the output shaft of the driving motor rotates continuously to cut threads automatically; or the lower end of the driving rod is connected with the driving cam from the rear side of the driving cam, when the backstitch needle pitch is the maximum value, the output shaft of the driving motor continues to rotate to automatically cut threads, and when the backstitch needle pitch is the maximum value, the output shaft of the driving motor continues to rotate to lift the presser foot;

when the maximum eccentric amount of the eccentric wheel is arranged back to the direction of the rear window of the machine shell: the lower end of the driving rod is connected with the driving cam from the front side of the driving cam, an output shaft of the driving motor rotates anticlockwise to lift the presser foot, when the stitch pitch of the front stitch is the maximum value, the output shaft of the driving motor rotates clockwise to lift the presser foot, the output shaft of the driving motor rotates clockwise to perform backstitch, and when the stitch pitch of the backstitch is the maximum value, the output shaft of the driving motor rotates continuously to perform automatic thread trimming; or the lower end of the driving rod is connected with the driving cam from the rear side of the driving cam, when the stitch length of the front seam is maximum, the output shaft of the driving motor continues to rotate to automatically cut the thread, and when the stitch length of the back seam is maximum, the output shaft of the driving motor continues to rotate to lift the presser foot.

In the mechanism of the single-motor driven backward and forward sewing, presser foot lifting and thread trimming device, as a second scheme of the first driving component, the first driving component comprises a crank and a crank connecting rod, the crank is fixedly arranged on an output shaft of the driving motor, one end of the crank connecting rod is connected with the crank, and the other end of the crank connecting rod is connected with the swinging seat.

In the mechanism of the single-motor driven backward and forward sewing, presser foot lifting and thread trimming device, when the maximum eccentric amount of the crank is arranged towards the rear window direction of the shell, the lower end of the driving rod is connected with the driving cam from the front side of the driving cam, the output shaft of the driving motor rotates anticlockwise to perform backward sewing, when the backstitch needle pitch is the maximum value, the output shaft of the driving motor continues to rotate to lift the presser foot, the output shaft of the driving motor rotates clockwise to perform forward sewing, and when the forward sewing needle pitch is the maximum value, the output shaft of the driving motor continues to rotate to perform automatic thread trimming; or the lower end of the driving rod is connected with the driving cam from the rear side of the driving cam, when the backstitch needle pitch is the maximum value, the output shaft of the driving motor continues to rotate to automatically cut threads, and when the backstitch needle pitch is the maximum value, the output shaft of the driving motor continues to rotate to lift the presser foot. In the technical scheme, a structure with a driving transmission rod can be adopted, and two modes that the driving transmission rod is not adopted and the driving rod is directly connected with the rear lever can also be adopted.

The technical scheme also provides a sewing machine which comprises the single motor driven mechanism for reversing sewing, lifting the presser foot and trimming the thread device.

Compared with the prior art, the mechanism of the utility model can realize the functions of reverse and forward seam switching, automatic presser foot lifting and automatic thread trimming through one motor, has compact structure and low manufacturing cost and use cost, and is convenient for operators to install, operate and use; the cost is effectively reduced, and the use effect of the sewing machine is improved.

Drawings

Fig. 1 is a schematic diagram of the explosive structure of the mechanism in the first embodiment.

Fig. 2 is a schematic view of a partially enlarged structure of the present mechanism according to the first embodiment.

Fig. 3 is a schematic front view of the mechanism according to the first embodiment.

FIG. 4 is a schematic side view of the mechanism according to the first embodiment.

Fig. 5 is a schematic front view of the present mechanism according to the second embodiment.

FIG. 6 is a schematic side view of the mechanism according to the second embodiment.

Fig. 7 is a schematic front view of the present mechanism in the third embodiment.

FIG. 8 is a schematic structural diagram of the present mechanism in a side view in the third embodiment.

Fig. 9 is a front view schematically showing the structure of the present mechanism in the fourth embodiment.

FIG. 10 is a schematic side view of the mechanism according to the fourth embodiment.

Fig. 11 is a front view schematically showing the structure of the present mechanism in the fifth embodiment.

FIG. 12 is a schematic side view of the mechanism according to the fifth embodiment.

Fig. 13 is a front view schematically showing the structure of the present mechanism in the sixth embodiment.

FIG. 14 is a schematic side view of the mechanism according to the sixth embodiment.

Fig. 15 is a front view schematically showing the structure of the present mechanism in the eighth embodiment.

FIG. 16 is a schematic side view showing the structure of the present mechanism in accordance with the eighth embodiment.

Fig. 17 is a front view schematically showing the structure of the present mechanism in the eighth embodiment.

FIG. 18 is a schematic side view of the mechanism according to the eighth embodiment.

In the figure, 1, a housing; 1a, mounting holes; 2. a swing seat; 3. a cutter shaft; 4. a rear lever; 4a, a strip-shaped open slot; 5. a drive motor; 61. an eccentric link; 62. an eccentric wheel; 62a, a large diameter portion; 62b, a small diameter part; 62c, a first eccentric hole; 63. an eccentric cover; 63a, a second eccentric hole; 64. a crank; 65. a crank connecting rod; 7. a drive cam; 8. A first bevel gear; 9. fixing the bolt; 10. a first shaft sleeve; 11. a second shaft sleeve; 12. a vertical shaft; 13. a second bevel gear; 14. a third bevel gear; 15. a fourth bevel gear; 16. tightening a ring; 17. A drive transmission rod; 18. a drive rod; 19. a pin shaft; 20. a limiting frame; 20a, a horizontal bending part; 20a1, vias; 21. a position-limiting tight ring; 22. a cushion pad; 23. a rear window; 24. A rear lever link.

Detailed Description

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

Example one

As shown in fig. 1 to 4, the sewing machine includes a housing 1, a swing seat 2 disposed in the housing 1 for changing between a forward direction and a backward direction and adjusting a needle pitch, a cutter shaft 3 for driving a thread cutting operation, and a rear lever 4 for driving a presser foot to lift, the mechanism includes a driving motor 5 fixedly disposed on the housing 1, an output shaft of the driving motor 5 extends into the housing 1, a first driving component connected to the swing seat 2 and capable of driving the swing seat to swing, a second driving component connected to the rear lever 4 and capable of driving the swing seat to swing, and a third driving component connected to the cutter shaft 3 and capable of driving the cutter shaft to rotate are sequentially disposed at intervals on the output shaft of the driving motor 5. Specifically, the second driving assembly comprises a driving cam 7 fixedly arranged on an output shaft of the driving motor 5, the third driving assembly comprises a bevel gear 8 fixedly arranged on an output shaft of the driving motor 5, the swinging seat 2 can swing around the mounting pin, and the needle pitch adjusting structure and the backstitch structure are connected with the swinging seat 2. The size of the needle pitch is adjusted by changing the position angle of the swinging seat 2; or when the swinging seat 2 swings to a preset angle, the state change between the backward sewing and the forward sewing is completed. In the embodiment, the driving motor 5 is fixedly arranged on the shell 1 of the sewing machine, and the driving component drives the swinging seat 2 to swing so as to achieve the purpose of reverse and forward sewing conversion; after the maximum needle pitch of the forward sewing or the backward sewing, the driving motor 5 continuously rotates and drives the rear lever 4 to swing through the driving cam 7 so as to achieve the purpose of lifting the presser foot, the driving motor 5 continuously rotates and drives the cutter shaft 3 through the bevel gear I8 just opposite to the presser foot lifting, and then the cutter shaft 3 drives the cutter rest to swing so as to achieve the purpose of trimming. The utility model can realize the functions of reverse and forward seam switching, automatic presser foot lifting and automatic thread trimming through one motor, has compact structure and low manufacturing cost and use cost, and is convenient for operators to install, operate and use; the cost is effectively reduced, and the use effect of the sewing machine is improved.

Further, as shown in fig. 1 and 2, a mounting hole 1a is formed in the machine case 1, the driving motor 5 is disposed outside the machine case 1 and is fixedly connected to the machine case 1 through a fixing bolt 9, and an output shaft of the driving motor 5 penetrates through the mounting hole 1a and extends into the machine case 1. The mounting hole 1a is obtained for a backstitch wrench shaft hole or based on the backstitch wrench shaft hole, and oil is sealed between the mounting hole 1a and an output shaft of the driving motor 5 through an oil seal piece. Furthermore, one end face of the driving motor 5 with an output shaft is abutted against the end face of the machine shell 1, and a sealing piece is arranged between the end face and the end face; the shell of the driving motor 5 is fixedly connected with the shell 1 through four fixing bolts 9; the end of the shell of the driving motor 5 is provided with a mounting boss, and the four fixing bolts 9 are distributed at four corners of the mounting boss, so that the whole structure is more compact, and the sealing performance is good.

As shown in fig. 2, fig. 3 and fig. 4, the first driving assembly includes an eccentric connecting rod 61 and an eccentric wheel 62 fixed on the output shaft of the driving motor 5, one end of the eccentric connecting rod 61 is sleeved on the eccentric wheel 62, and the other end is hinged to one side of the swing seat 2. Specifically, the eccentric wheel 62 includes a large diameter portion 62a and a small diameter portion 62b which are coaxially arranged, a first eccentric hole 62c is arranged on the large diameter portion 62a and the small diameter portion 62b, the axis of the first eccentric hole 62c is arranged in parallel with the axis of the large diameter portion 62a and the small diameter portion 62b, and the output shaft of the driving motor 5 passes through the first eccentric hole 62 c; one end of the eccentric connecting rod 61 is sleeved on the small-diameter part 62b, an eccentric cover 63 is arranged on the outer end face of the small-diameter part 62b, a second eccentric hole 63a for the output shaft of the driving motor 5 to pass through is arranged on the eccentric cover 63, the eccentric cover 63 is fixedly arranged on the outer end face of the small-diameter part 62b and limits the eccentric connecting rod 61 in the axial direction, and the first eccentric hole 62c and the second eccentric hole 63a are arranged coaxially. A vertical shaft sleeve I10 and a transverse shaft sleeve II 11 are arranged on the machine shell 1, a vertical shaft 12 is rotatably inserted in the shaft sleeve I10, a bevel gear II 13 and a bevel gear III 14 are fixedly arranged at the upper end and the lower end of the vertical shaft 12 respectively, and the bevel gear II 13 is meshed with the bevel gear I8; the cutter shaft 3 is rotatably inserted in the second shaft sleeve 11, one end of the cutter shaft 3 is fixedly provided with a tight ring 16, the other end of the cutter shaft is fixedly provided with a fourth bevel gear 15, and the fourth bevel gear 15 is meshed with the third bevel gear 14. A driving transmission rod 17 is arranged on the machine shell 1, one end of the driving transmission rod 17 is hinged on the machine shell 1, the driving cam 7 is connected with the middle part of the driving transmission rod 17 through a driving rod 18, and a pin shaft 19 is arranged at the other end of the driving transmission rod 17; the middle part of the rear lever 4 is rotatably connected on the machine shell 1, one end of the rear lever 4 is provided with a strip-shaped open slot 4a, and the pin shaft 19 is embedded in the strip-shaped open slot 4a in a sliding manner.

As shown in fig. 1 and 2, a limiting frame 20 is further fixedly disposed on the housing 1, a horizontal bent portion 20a is disposed on the limiting frame 20, a through hole 20a1 for the driving rod 18 to pass through is disposed on the horizontal bent portion 20a, a limiting tight ring 21 is disposed on the driving rod 18, the lower end of the driving rod 18 passes through the through hole 20a1 and is connected with the driving cam 7, the limiting tight ring 21 is limited on the horizontal bent portion 20a, and a cushion pad 22 is disposed between the limiting tight ring 21 and the horizontal bent portion 20 a.

As shown in fig. 3 and 4, when the maximum eccentric amount of the eccentric wheel 62 is set toward the rear window 23 of the housing 1: the lower end of the driving rod 18 is connected with the driving cam 7 from the front side of the driving cam 7, the output shaft of the driving motor 5 rotates anticlockwise to perform backstitch, when the backstitch needle pitch is maximum, the output shaft of the driving motor 5 continues to rotate to lift the presser foot, the output shaft of the driving motor 5 rotates clockwise to perform main stitch, and when the main stitch needle pitch is maximum, the output shaft of the driving motor 5 continues to rotate to perform automatic thread trimming.

In the present embodiment, the driving motor 5 is a stepping motor or a servo motor, and preferably a stepping motor. The front side in the present embodiment means that, with reference to fig. 1, the direction of the drive motor 5 is left, the other side is right, the lower end of the drive lever 18 is forward when the drive cam 7 is blocked toward the window, and is rearward when the drive cam 7 is not blocked.

The installation steps of the parts in the embodiment are as follows:

firstly, other parts of the automatic wire cutting structure except the bevel gear I8 are preferentially installed in the position. Firstly, reforming and shaping a machine shell 1, normally assembling the machine according to the original assembly, firstly, knocking a first shaft sleeve 10 and a second shaft sleeve 11 in an automatic wire cutting structure into corresponding positions of the machine shell 1 and installing the machine shell in place, then the vertical shaft 12 is inserted into the hole of the first shaft sleeve 10 from bottom to top, simultaneously the second bevel gear 13 is sleeved into the vertical shaft 12 from the upper end and is installed in place by the locking screw, the third bevel gear 14 is sleeved into the vertical shaft 12 from the lower end of the vertical shaft 12 and is installed in place by the locking screw, the cutter shaft 3 is inserted into the machine shell 1 from the position of the original cutter shaft at the front end of the machine shell 1 to replace the original cutter shaft, then sleeved with a tight ring 16, inserted into a hole of the second shaft sleeve 11, sleeved with a fourth bevel gear 15, adjusting the gap between the third bevel gear 14 and the fourth bevel gear 15, locking a fastening screw at the fourth bevel gear 15, then the tight ring 16 is locked at the other end of the second shaft sleeve 11 and the axial clearance is noticed, and finally a tool rest is sleeved at the corresponding end of the cutter shaft 3; and finishing the assembly of the parts at the earlier stage of the automatic trimming structure.

The other parts are continuously assembled, firstly, the big end of the eccentric connecting rod 61 is sleeved on the corresponding position of the eccentric wheel 62, the eccentric cover 63 is placed on the corresponding position of the small end surface of the eccentric wheel 62, and the eccentric cover is locked by a screw. Knocking a framework oil seal into a corresponding position hole of a machine shell 1, inserting a driving motor 5 into the machine shell 1 through the framework oil seal, sequentially sleeving an eccentric wheel 62, a driving cam 7 and a bevel gear I8 from the inner cavity of the machine shell 1 to corresponding positions, sleeving a small head end of an eccentric connecting rod 61 on a corresponding pin of a swinging seat 2, clamping the small head end of the eccentric connecting rod 61 into a corresponding clamping groove of the swinging seat 2 by using a clamping spring so as to limit and connect the eccentric connecting rod 61, inserting a rear lever connecting rod 24 into a corresponding hole of a rear lever 4, fixing the rear lever connecting rod to the corresponding position of the machine shell 1 by using a shaft position screw, and simultaneously replacing an original rear lever 4 component of the machine. The driving rod 18 and the cylindrical pin are sequentially inserted into the corresponding position holes of the driving transmission rod 17 and are locked by nuts, and the driving transmission rod 17 is connected to the corresponding position of the machine shell 1 by a shaft position screw. The limit retainer 21, the cushion 22 and the limit frame 20 are sequentially sleeved in the driving rod 18 and fixed to corresponding positions by screws and bolts respectively.

Then the driving motor 5 is electrified to search the zero position of the driving motor 5, the eccentric wheel 62 is adjusted to search the mechanical zero position and the mechanical zero position is locked by a screw, the machine is operated to the maximum backstitch needle pitch state, the driving cam 7 is adjusted to the corresponding position and the mechanical zero position is locked by the screw, the machine is operated to the maximum backstitch needle pitch state, the bevel gear I8 is adjusted to the corresponding position, meanwhile, the gap between the bevel gear I8 and the bevel gear II 13 is adjusted, and the mechanical zero position is locked by the screw, so that the assembly process is basically finished.

The control system controls the eccentric wheel 62 to rotate anticlockwise or clockwise to control the swinging seat 2 to swing, thereby achieving the purpose of controlling the backward and forward sewing. When the presser foot needs to be lifted, the driving motor 5 can be controlled to rotate anticlockwise until the backstitch stitch length is maximum, the driving motor continues to rotate, the driving cam 7, the driving rod 18 and the driving transmission rod 17 drive the rear lever 4 to swing, so that the purpose of lifting the presser foot is achieved, and meanwhile, the function of manual knee control is reserved through the rear lever connecting rod 24; when thread cutting is needed, the driving motor 5 can be controlled to rotate clockwise to the maximum distance of the positive sewing needle and continue to rotate, and the cutter frame is driven to swing through the bevel gear I8, the bevel gear II 13, the vertical shaft 12, the bevel gear III 14, the bevel gear IV 15 and the cutter shaft 3, so that the purpose of thread cutting is achieved.

Example two

As shown in fig. 1, the present embodiment is substantially the same as the first embodiment, except that the structure of the present embodiment is substantially the same as that of the first embodiment, and the differences are as follows: the lower end of the drive lever 1814 of the present embodiment is connected to the drive cam 7 from the rear side of the drive cam 713. The rotating shaft 5 of the driving motor 52 rotates clockwise to realize backstitch, and the purpose of lifting the presser foot is achieved by continuously rotating the rotating shaft 5 of the driving motor 52 when the backstitch gauge is maximum.

Example two

As shown in fig. 5 and 6, the present embodiment is substantially the same as the first embodiment except that the lower end of the drive lever 18 is connected to the drive cam 7 from the rear side of the drive cam 7, and the output shaft of the drive motor 5 continues to rotate to perform automatic thread cutting at the maximum backstitch, and the output shaft of the drive motor 5 continues to rotate to perform presser foot lifting at the maximum backstitch.

EXAMPLE III

As shown in fig. 7 and 8, the present embodiment is substantially the same as the first embodiment except that the maximum eccentric amount of the eccentric wheel 62 is set back toward the rear window 23 of the housing 1 in the present embodiment, and as the name suggests, the maximum eccentric amount of the eccentric wheel 62 is set back toward the rear window 23. At this time, the lower end of the drive lever 18 is connected to the drive cam 7 from the front side of the drive cam 7, the counterclockwise rotation of the output shaft of the drive motor 5 is a normal stitch, the continuous rotation of the output shaft of the drive motor 5 lifts the presser foot at the maximum value of the normal stitch pitch, the clockwise rotation of the output shaft of the drive motor 5 is a reverse stitch, and the continuous rotation of the output shaft of the drive motor 5 is an automatic thread trimming at the maximum value of the reverse stitch pitch.

Example four

As shown in fig. 9 and 10, the present embodiment is substantially the same as the third embodiment, except that in the present embodiment, the lower end of the drive lever 18 is connected to the drive cam 7 from the rear side of the drive cam 7, and when the normal stitch pitch is maximum, the output shaft of the drive motor 5 continues to rotate to perform automatic thread trimming, and when the backstitch is maximum, the output shaft of the drive motor 5 continues to rotate to perform presser foot lifting.

EXAMPLE five

As shown in fig. 11 and 12, as a second scheme for connecting the driving cam 7 with the rear lever 4, the middle part of the rear lever 4 is rotatably connected to the housing 1, a vertical driving rod 18 is arranged on the driving cam 7, and the upper end of the driving rod 18 is hinged with one end of the rear lever 4.

EXAMPLE six

As shown in fig. 13 and 14, the present embodiment is substantially the same as the first embodiment, except that, as a second solution of the first driving assembly, the first driving assembly in the present embodiment includes a crank 64 and a crank connecting rod 65, the crank 64 is fixed on the output shaft of the driving motor 5, one end of the crank connecting rod 65 is connected to the crank 64, and the other end of the crank connecting rod 65 is connected to the swing seat 2.

EXAMPLE seven

As shown in fig. 13 and 14, the present embodiment is substantially the same as the sixth embodiment, in the present embodiment, the maximum eccentric amount of the crank 64 is provided toward the rear window 23 of the housing 1, the lower end of the driving lever 18 is connected to the driving cam 7 from the rear side of the driving cam 7, the output shaft of the driving motor 5 continues to rotate to automatically cut the thread at the maximum backstitch distance, and the output shaft of the driving motor 5 continues to rotate to lift the presser foot at the maximum backstitch distance.

Example eight

As shown in fig. 15 to 18, the present embodiment is substantially the same as the seventh embodiment, except that in the present embodiment, the lower end of the drive lever 18 is connected to the drive cam 7 from the front side of the drive cam 7, the counterclockwise rotation of the output shaft of the drive motor 5 is set as backstitch, when the backstitch pitch is maximum, the output shaft of the drive motor 5 continues to rotate to lift the presser foot, the clockwise rotation of the output shaft of the drive motor 5 is set as backstitch, and when the backstitch pitch is maximum, the output shaft of the drive motor 5 continues to rotate to automatically cut the thread.

In the seventh and eighth embodiments, the structure with the driving transmission rod 17 may be adopted, and two modes that the driving transmission rod 17 is not adopted and the driving rod 18 is directly connected with the rear lever 4 may be adopted.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Although 1, a housing is used more herein; 1a, mounting holes; 2. a swing seat; 3. A cutter shaft; 4. a rear lever; 4a, a strip-shaped open slot; 5. a drive motor; 61. an eccentric link; 62. an eccentric wheel; 62a, a large diameter portion; 62b, a small diameter part; 62c, a first eccentric hole; 63. an eccentric cover; 63a, a second eccentric hole; 64. a crank; 65. a crank connecting rod; 7. A drive cam; 8. a first bevel gear; 9. fixing the bolt; 10. a first shaft sleeve; 11. a second shaft sleeve; 12. a vertical shaft; 13. a second bevel gear; 14. a third bevel gear; 15. a fourth bevel gear; 16. Tightening a ring; 17. a drive transmission rod; 18. a drive rod; 19. a pin shaft; 20. a limiting frame; 20a, a horizontal bending part; 20a1, vias; 21. a position-limiting tight ring; 22. a cushion pad; 23. A rear window; 24. rear lever links, etc., but does not exclude the possibility of using other terms. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed in a manner that is inconsistent with the spirit of the invention.

Claims (10)

1. The sewing machine comprises a machine shell (1), a swing seat (2) arranged in the machine shell (1) and used for reversing sewing and adjusting needle pitch, a cutter shaft (3) used for driving thread cutting and a rear lever (4) used for driving the presser foot to lift, and is characterized in that the mechanism comprises a driving motor (5) fixedly arranged on the machine shell (1), an output shaft of the driving motor (5) extends into the machine shell (1), and a first driving component connected with the swing seat (2) and capable of driving the swing, a second driving component connected with the rear lever (4) and capable of driving the swing and a third driving component connected with the cutter shaft (3) and capable of driving the cutter shaft to rotate are arranged on the output shaft of the driving motor (5) at intervals.

2. The mechanism of the single-motor driven backward and forward sewing, presser foot lifting and trimming device according to claim 1, characterized in that the housing (1) is provided with a mounting hole (1a), the driving motor (5) is arranged outside the housing (1) and is fixedly connected to the housing (1) through a fixing bolt (9), and an output shaft of the driving motor (5) penetrates through the mounting hole (1a) and extends into the housing (1).

3. The mechanism of the single-motor driven backward and forward sewing, presser foot lifting and trimming device according to claim 1 or 2, characterized in that the driving assembly one comprises an eccentric connecting rod (61) and an eccentric wheel (62) fixedly arranged on the output shaft of the driving motor (5), one end of the eccentric connecting rod (61) is sleeved on the eccentric wheel (62), and the other end is hinged with one side of the swinging seat (2).

4. The mechanism of the single-motor driven backstitch, presser foot and thread trimming device according to claim 3, wherein the eccentric wheel (62) comprises a large diameter part (62a) and a small diameter part (62b) which are coaxially arranged, a first eccentric hole (62c) is arranged on the large diameter part (62a) and the small diameter part (62b), the axis of the first eccentric hole (62c) is arranged in parallel with the axes of the large diameter part (62a) and the small diameter part (62b), and the output shaft of the driving motor (5) passes through the first eccentric hole (62 c); one end of the eccentric connecting rod (61) is sleeved on the small-diameter portion (62b) and an eccentric cover (63) is arranged on the outer end face of the small-diameter portion (62b), a second eccentric hole (63a) for an output shaft of the driving motor (5) to penetrate is formed in the eccentric cover (63), the eccentric cover (63) is fixedly arranged on the outer end face of the small-diameter portion (62b) and limits the eccentric connecting rod (61) in the axial direction, and the first eccentric hole (62c) and the second eccentric hole (63a) are coaxially arranged.

5. The mechanism of single motor driven backstitch, presser foot and thread trimmer device of claim 3, characterized in that said driving assembly three comprises a bevel gear one (8) fixed on the output shaft of said driving motor (5); a first vertical shaft sleeve (10) and a second horizontal shaft sleeve (11) are arranged on the machine shell (1), a vertical shaft (12) is rotatably inserted into the first shaft sleeve (10), a second bevel gear (13) and a third bevel gear (14) are fixedly arranged at the upper end and the lower end of the vertical shaft (12) respectively, and the second bevel gear (13) is meshed with the first bevel gear (8); the cutter shaft (3) is rotatably inserted in the second shaft sleeve (11), one end of the cutter shaft (3) is fixedly provided with a tight ring (16), the other end of the cutter shaft is fixedly provided with a fourth bevel gear (15), and the fourth bevel gear (15) is meshed with the third bevel gear (14).

6. The mechanism of the single motor driven backstitch, presser foot and thread trimming device according to claim 3, wherein the second driving assembly comprises a driving cam (7) fixedly arranged on an output shaft of the driving motor (5); a driving transmission rod (17) is arranged on the machine shell (1), one end of the driving transmission rod (17) is hinged to the machine shell (1), the driving cam (7) is connected with the middle part of the driving transmission rod (17) through a driving rod (18), and a pin shaft (19) is arranged at the other end of the driving transmission rod (17); the middle part of the rear lever (4) is rotatably connected to the shell (1), one end of the rear lever (4) is provided with a strip-shaped open slot (4a), and the pin shaft (19) is embedded in the strip-shaped open slot (4a) in a sliding manner; still set firmly spacing (20) on casing (1), be provided with horizontal bending portion (20a) on spacing (20), be provided with through-hole (20a1) that supply actuating lever (18) to pass through on horizontal bending portion (20a), be provided with spacing tightring (21) on actuating lever (18), the lower extreme of actuating lever (18) is passed through-hole (20a1) with drive cam (7) are connected, spacing tightring (21) are spacing on horizontal bending portion (20a) just be provided with blotter (22) between spacing tightring (21) and the horizontal bending portion (20 a).

7. The mechanism of the single-motor driven backward and forward sewing, presser foot lifting and thread trimming device according to claim 6, characterized in that the middle part of the rear lever (4) is rotatably connected to the machine shell (1), the driving cam (7) is provided with a vertical driving rod (18), and the upper end of the driving rod (18) is hinged with one end of the rear lever (4).

8. The mechanism of the single-motor driven backward and forward sewing, presser foot lifting and thread trimming device according to claim 1 or 2, characterized in that the driving assembly one comprises a crank (64) and a crank connecting rod (65), the crank (64) is fixedly arranged on the output shaft of the driving motor (5), one end of the crank connecting rod (65) is connected with the crank (64), and the other end of the crank connecting rod (65) is connected with the swinging seat (2).

9. The mechanism of the single motor driven backstitch, presser foot and thread trimming device according to claim 8, characterized in that the second driving assembly comprises a driving cam (7) fixed on the output shaft of the driving motor (5).

10. A sewing machine comprising a single motor driven reversible sewing, presser foot lifting and thread trimming device mechanism as claimed in any one of claims 1 to 9.

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