CN215517905U

CN215517905U - Automatic lift presser foot mechanism

Info

Publication number: CN215517905U
Application number: CN202121398143.4U
Authority: CN
Inventors: 王华青; 童辉
Original assignee: Zhejiang Jiadao Sewing Machine Co ltd
Current assignee: Zhejiang Jiadao Sewing Machine Co ltd
Priority date: 2021-06-22
Filing date: 2021-06-22
Publication date: 2022-01-14
Anticipated expiration: 2031-06-22

Abstract

The utility model belongs to the technical field of sewing machines, and particularly relates to an automatic presser foot lifting mechanism which comprises a presser foot component; the elastic component is connected with the presser foot component and is used for providing pressing force for the presser foot component; the driving assembly is connected with the elastic assembly and is used for adjusting the compression amount of the elastic assembly; the elastic component is pressed between the presser foot component and the driving component; the elastic assembly includes: a buffer spring connected to the driving assembly, the driving assembly compressing the buffer spring; one end of the compression spring is connected with the buffer spring, and the other end of the compression spring is connected with the presser foot component; when the buffer spring is compressed, the pressing spring is pressed by the buffer spring, and the pressing spring presses the presser foot assembly again. The buffer spring is used as a buffer component of the pressing spring and the pressing foot component, so that the movement of the pressing foot component and the elastic component is smoother, and the instant acting force between the parts is smaller.

Description

Automatic lift presser foot mechanism

Technical Field

The utility model relates to the technical field of sewing machines, in particular to an automatic presser foot lifting mechanism.

Background

Most of existing lockstitch sewing machines utilize a knee rest device to achieve a function of lifting a presser foot, on some thick material lockstitch sewing machines, due to the fact that sewing materials are too thick, a presser foot spring is needed to provide large pressing force for a presser foot assembly, and a cloth feeding function can be normally performed, so that the knee rest device can completely lift the presser foot assembly only by overcoming the large pressing force of the presser foot spring in the presser foot lifting process, and labor intensity and operation difficulty of an operator are large.

The problem can be solved by the labor-saving knee rest device, the sewing machine and the presser foot lifting method which are disclosed in the Chinese patent application No. 201910233015.5, and the defect is that only one presser foot spring is provided, the spring is too direct in lifting and releasing and pressing the presser foot when descending, the direct resilience of the spring can cause larger acting force to relevant mechanisms of the presser foot, the service life of parts is shortened, and even the parts are damaged.

Disclosure of Invention

The utility model aims to provide an automatic presser foot lifting mechanism, which increases the force transmission layer number through two springs, namely a buffer spring and a compression spring, takes the buffer spring as a buffer component and solves the problem that the resilience of a single spring in the automatic presser foot lifting mechanism is large in acting force on parts.

The purpose of the utility model is realized as follows:

an automatic presser foot lifting mechanism comprises

A presser foot assembly;

the elastic component is connected with the presser foot component and is used for providing pressing force for the presser foot component; and

the driving assembly is connected with the elastic assembly and is used for adjusting the compression amount of the elastic assembly;

the elastic component is pressed between the presser foot component and the driving component;

the elastic assembly includes:

a buffer spring connected to the driving assembly, the driving assembly compressing the buffer spring; and

one end of the compression spring is connected with the buffer spring, and the other end of the compression spring is connected with the presser foot component;

when the buffer spring is compressed, the pressing spring is pressed by the buffer spring, and the pressing spring presses the presser foot assembly again.

Preferably, the drive assembly comprises:

a drive member;

one end of the screw rod is connected with the driving piece and is driven by the driving piece to rotate; and

the driving frame is in threaded connection with the screw rod; one end of the buffer spring is connected with the driving frame;

the buffer spring and the compression spring are sleeved on the screw rod.

Preferably, the presser foot assembly comprises:

a presser foot;

a pressing rod which is connected with the presser foot and can move up and down along the screw rod; and

the guide block is arranged on a shell of the sewing machine in a sliding mode, and the pressure lever is fixedly arranged on the guide block;

one ends of the buffer spring and the pressing spring are pressed between the driving frame and the guide block.

Preferably, the guide block is provided with a vertical fixing hole for mounting the compression bar; one side of the guide block is also provided with a transverse fixing hole which is communicated with the vertical fixing hole; the tail end of the fastener penetrates through the transverse fixing hole to extend into the vertical fixing hole and abut against the pressure rod, so that the pressure rod is fixed on the guide block.

Preferably, the driving frame is provided with a long slot hole, the fastener passes through the long slot hole and is arranged on the guide block, and when the driving frame moves upwards and the fastener abuts against the lower end part of the long slot hole, the driving frame drives the guide block to move upwards.

Preferably, the shell is provided with a guide groove, a sliding block is formed on one side of the guide block, the sliding block is arranged in the guide groove, and two ends of the guide groove are used for limiting the guide block when moving up and down.

Preferably, the presser foot assembly further comprises:

the loop bar is fixedly arranged on the shell; one end of the loop bar is positioned in the shell, and the other end of the loop bar extends to the outer side of the shell; the pressure lever is arranged in the loop bar in a penetrating way.

Preferably, a groove is formed in the upper end of the compression bar, and the end of the screw rod can extend into the groove.

Preferably, the elastic coefficient of the buffer spring is smaller than that of the pressing spring.

Preferably, the driving piece is a stepping motor, and the screw rod is connected with the stepping motor through a coupler.

Compared with the prior art, the utility model has the outstanding and beneficial technical effects that:

1. according to the utility model, the buffer spring is used as the buffer component of the pressing spring and the presser foot component, the number of force transmission layers between the components in the presser foot lifting mechanism is increased, so that the movement of the presser foot component and the elastic component is smoother, the instant acting force between the components is smaller, further the components in the presser foot lifting mechanism can be prevented from being damaged due to the action of larger external force, and the service life of the components in the presser foot lifting mechanism is finally prolonged.

2. According to the utility model, the up-and-down movement of the guide block is limited by the upper end and the lower end of the guide groove, so that the presser foot component connected with the guide block is prevented from being lifted too high or moving too much downwards. The left side wall and the right side wall of the guide groove are attached to the sliding block, so that the transverse movement of the guide block is limited, the guide block is guided by the guide groove, the guide block can only move up and down, and the stability is improved.

3. The pressure lever is arranged in the loop bar in a penetrating mode and extends to the outer side of the loop bar, so that the pressure lever is protected through the loop bar, meanwhile, the position of the pressure lever can be limited through the loop bar, the pressure lever can only move along the axis direction of the loop bar, and the stability of the pressure lever during moving is further guaranteed.

Drawings

Fig. 1 is a schematic view of a structure applied to a sewing machine according to the present invention.

Fig. 2 is a schematic view of the overall structure of the present invention.

Fig. 3 is an exploded view of fig. 2.

Fig. 4 is a cross-sectional view of the present invention.

Reference numerals: 1-a presser foot assembly; 2-an elastic component; 3-a drive assembly; 4-a buffer spring; 5-a compression spring; 6-a driving member; 7-a screw rod; 8-a driving frame; 9-presser foot; 10-a compression bar; 11-a guide block; 12-vertical fixing holes; 13-transverse fixing holes; 14-a fastener; 15-slotted hole; 16-a guide groove; 17-a slide block; 18-a loop bar; 19-a groove; 20-a coupler; 21-shell.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

An automatic presser foot lifting mechanism, which is generally applied to a sewing machine, as shown in fig. 1-4, comprises a presser foot assembly 1, an elastic assembly 2 and a driving assembly 3. The driving assembly 3 is fixedly arranged on the sewing machine, the elastic assembly 2 is connected with the driving assembly 3, the presser foot assembly 1 is connected with the driving assembly 3 and the elastic assembly 2, the elastic assembly 2 is arranged between the presser foot assembly 1 and the driving assembly 3 in a pressing mode, and the presser foot assembly 1 and the driving assembly 3 are used as the supporting positions of the elastic assembly 2 when the two ends of the presser foot assembly rebound and compress. The driving component 3 drives the presser foot component 1 to move up and down, and the elastic component 2 provides pressing force for the presser foot component 1, so that the presser foot component 1 presses cloth. Meanwhile, the driving assembly 3 also applies force to the elastic assembly 2, and the force is used for adjusting the compression amount of the elastic assembly 2, so that the pressing force of the elastic assembly 2 on the presser foot assembly 1 is adjusted.

Referring to fig. 2 and 3, the elastic member 2 includes a buffer spring 4 and a pressing spring 5. There are a plurality of springs of the elastic assembly 2, and in the present embodiment, it is preferable that the number of the buffer springs 4 and the number of the pressing springs 5 are one. Buffer spring 4 is connected with drive assembly 3, and compression spring 5's one end is connected with buffer spring 4, and the other end is connected with presser foot subassembly 1. After the driving assembly 3 compresses the buffer spring 4, the pressing spring 5 is compressed by the buffer spring 4, and the pressing spring 5 presses the pressing foot assembly 1 again to compress the cloth.

When the presser foot assembly 1 descends to press the cloth, the buffer spring 4 is compressed, then the pressing spring 5 is compressed, and finally the pressing spring 5 provides pressing force for the presser foot assembly 1, so that the presser foot assembly 1 presses the cloth. When the presser foot assembly 1 rises to loosen cloth, the buffer spring 4 rebounds firstly, the pressing spring 5 is not pressed any more, the pressing spring 5 rebounds again, and when the pressing spring 5 does not provide pressing force for the presser foot assembly 1 any more, the driving assembly 3 can drive the presser foot assembly 1 to move upwards. Therefore, the buffer spring 4 is used as a buffer component of the pressure spring 5 and the pressure foot component 1, the number of transmission layers of force between components in the pressure foot 9 lifting mechanism is increased, the movement of the pressure foot component 1 and the elastic component 2 is smoother, the instant acting force between the components is smaller, further, the components in the pressure foot 9 lifting mechanism can be prevented from being damaged due to the action of large external force, and the service life of the components in the pressure foot 9 lifting mechanism is finally prolonged.

In the embodiment, the buffer spring 4 is preferably a thin spring, and the pressing spring 5 is preferably a thick spring, that is, the elastic coefficient of the buffer spring 4 is smaller than that of the pressing spring 5, and the buffer spring 4 is pressed more easily under force. Thereby making the transmission of force between the buffer spring 4 and the pressing spring 5 more apparent. Only when the buffer spring 4 is compressed to a large extent, the hold-down spring 5 can start to be compressed; when the buffer spring 4 rebounds, the compression spring 5 will begin to rebound. Further, the cushioning performance of the cushion spring 4 is further improved by the thin cushion spring 4, and the pressing spring 5 is prevented from generating a large acting force.

Referring to fig. 2 and 4, the driving assembly 3 includes a driving member 6, a lead screw 7, and a driving frame 8. The driving member 6 is fixedly provided on a housing 21 of the sewing machine. One end of the screw rod 7 is connected with the driving piece 6, and the other end is connected with the presser foot component 1. One end of the driving frame 8 is sleeved on the screw rod 7, and the end is in threaded connection with the screw rod 7. The buffer spring 4 and the pressing spring 5 are sleeved on the screw rod 7, and one end of the buffer spring 4 is connected with the driving frame 8 and is positioned on one side of the driving frame 8 close to the presser foot assembly 1.

The driving piece 6 is used for driving the screw rod 7 to rotate, the screw rod 7 rotates and then drives the driving frame 8 to move up and down through threaded connection, and therefore when the driving frame 8 moves downwards, the buffer spring 4 and the compression spring 5 are compressed, the presser foot assembly 1 is driven to move downwards, and the presser foot assembly 1 is compressed. As shown in fig. 2, the driving member 6 is preferably a stepping motor in this embodiment, and the lead screw 7 is connected to the stepping motor through a coupling 20, so that the lead screw 7 can be precisely controlled by the stepping motor. When the stepping motor rotates for more circles, the driving frame 8 of the screw rod 7 can move downwards for more strokes, so that the compression amount of the elastic component 2 is larger, and the pressing force on the presser foot component 1 is larger. When the stepping motor rotates for a few turns, the lead screw 7 driving frame 8 can move downwards for a small distance, so that the compression amount of the elastic component 2 is reduced, and the pressing force on the presser foot component 1 is reduced. And further realize the accurate control of the pressing force when the presser foot assembly 1 presses the cloth.

As shown in fig. 2, the presser foot assembly 1 includes a presser foot 9, a pressing rod 10, and a guide block 11. One end of the pressure lever 10 is connected with the end of the screw rod 7, the other end is connected with the pressure foot 9, and the pressure lever 10 can move up and down along the screw rod 7. The guide block 11 is slidably disposed on a housing 21 of the sewing machine, and the presser bar 10 is fixedly disposed on the guide block 11. One end of the pressing spring 5 is abutted against the guide block 11, namely, the buffer spring 4 and the pressing spring 5 are pressed between the driving frame 8 and the guide block 11. Therefore, the driving piece 6 drives the screw rod 7 to rotate, the screw rod 7 rotates to drive the driving frame 8 to move towards the guide block 11, so that the buffer spring 4 and the compression spring 5 are compressed, the guide block 11 is driven to slide downwards, the compression bar 10 is driven to move downwards, and finally the compression and the descending of the presser foot 9 are realized.

With reference to fig. 3 and 4, a vertical fixing hole 12 for installing the pressing rod 10 is formed in the guide block 11, a horizontal fixing hole 13 is further formed in one side of the guide block 11, the horizontal fixing hole 13 is communicated with the vertical fixing hole 12, so that the pressing rod 10 is prevented from rotating and moving up and down on the guide block 11 by penetrating the horizontal fixing hole 13 through a fastener 14, and the tail end of the fastener 14 extends into the vertical fixing hole 12 and abuts against the pressing rod 10, thereby ensuring that the pressing rod 10 is fixed on the guide block 11.

Referring to fig. 2 and 3, the driving frame 8 is provided with a long slot 15, and the fastener 14 is disposed on the guide block 11 through the long slot 15. When the driving frame 8 moves upwards and the fastening piece 14 is not abutted against the lower end part of the long slotted hole 15, the driving frame 8 rises, namely the elastic component 2 relaxes and rebounds, the buffer spring 4 relaxes and rebounds first, then the pressing spring 5 relaxes and rebounds, and finally the pressing force applied to the presser foot component 1 can be slowly and stably reduced, so that the acting force between parts is reduced. When the driving frame 8 moves upwards and the fastening piece 14 abuts against the lower end part of the long slotted hole 15, the driving frame 8 can drive the guide block 11 to move upwards, at the moment, the elastic component 2 does not apply force to the presser foot 9 any more, or only has small force, so that the guide block 11 can be more stable when driving the presser foot component 1 to rise, and is not easy to be influenced by the elastic component 2.

As shown in fig. 1, a guide groove 16 is formed on the housing 21, a slider 17 is formed on one side of the guide block 11, and the slider 17 is disposed in the guide groove 16, so that the guide block 11 slides on the housing 21. Meanwhile, the up-and-down movement of the guide block 11 can be limited through the upper end and the lower end of the guide groove 16, and the presser foot component 1 connected with the guide block 11 is prevented from being lifted too high or moving too much downwards. The left and right side walls of the guide groove 16 are also attached to the slider 17, so that the lateral movement of the guide block 11 is limited, the guide block 11 is guided by the guide groove 16, the guide block 11 can only move up and down, and the stability is improved.

Further, with reference to fig. 1 and 4, the presser foot assembly 1 further includes a loop bar 18, the loop bar 18 is fixedly disposed on the housing 21, one end of the loop bar 18 is located in the housing 21, and the other end extends to the outside of the housing 21. The compression bar 10 penetrates through the sleeve rod 18 and extends to the outer side of the sleeve rod 18, so that the compression bar 10 is protected by the sleeve rod 18, meanwhile, the compression bar 10 can be limited by the sleeve rod 18, the compression bar 10 can only move along the axis direction of the sleeve rod 18, and the stability of the movement of the compression bar 10 is further ensured.

The above-described effects can be achieved without the end portions between the presser bar 10 and the lead screw 7 being connected together, i.e., without an overlapping portion, but overlapping the end portions of the presser bar 10 and the lead screw 7 can make the presser bar 10 more stable when moving up and down in the axial direction of the lead screw 7. As shown in fig. 4, a groove 19 is formed at the upper end of the pressing rod 10, and an opening of the groove 19 is located at the upper end of the pressing rod 10, so that when the guide block 11 drives the pressing rod 10 to move up and down, the lower end of the screw rod 7 can extend into the groove 19, so that the pressing rod 10 can move up and down on the screw rod 7, and meanwhile, the end of the screw rod 7 abuts against the inner wall of the groove 19 to limit the transverse movement of the pressing rod 10 and prevent the pressing rod 10 from shaking.

The specific working process of the scheme is as follows:

when cloth needs to be compressed tightly, the driving piece 6 rotates to drive the screw rod 7 to rotate, the screw rod 7 rotates to drive the driving frame 8 to move downwards, the driving frame 8 compresses the buffer spring 4, then compresses the compression spring 5, then applies force downwards to the guide block 11 through the compression spring 5 to drive the guide block 11 to move downwards, and finally the guide block 11 drives the presser foot assembly 1 to press downwards, so that the cloth can be compressed tightly.

When the presser foot 9 needs to be lifted, the driving piece 6 rotates reversely to drive the screw rod 7 to rotate reversely, so that the driving piece 6 is driven to move upwards, the driving frame 8 does not exert downward force on the buffer spring 4, the buffer spring 4 rebounds, the compression spring 5 rebounds, and the spring assembly does not provide pressing force for the presser foot assembly 1 any more; when the lower end of the upper long slotted hole 15 of the driving frame 8 abuts against the fastening piece 14, the driving frame 8 drives the guide block 11 to move upwards, and finally the guide block 11 drives the presser foot assembly 1 to ascend, so that the presser foot 9 is lifted.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the utility model as claimed. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. An automatic presser foot lifting mechanism comprises

A presser foot assembly (1);

the elastic component (2) is connected with the presser foot component (1) and is used for providing pressing force for the presser foot component (1); and

the driving assembly (3) is connected with the elastic assembly (2) and is used for adjusting the compression amount of the elastic assembly (2);

it is characterized in that the preparation method is characterized in that,

the elastic component (2) is arranged between the presser foot component (1) and the driving component (3) in a pressing mode;

the elastic assembly (2) comprises:

a buffer spring (4) connected to the drive assembly (3), the drive assembly (3) compressing the buffer spring (4); and

a compression spring (5), one end of which is connected with the buffer spring (4), and the other end of which is connected with the presser foot component (1);

when the buffer spring (4) is compressed, the pressing spring (5) is compressed by the buffer spring (4), and the pressing spring (5) presses the presser foot assembly (1) again.

2. The automatic presser foot lifting mechanism of claim 1, wherein: the drive assembly (3) comprises:

a driver (6);

one end of the screw rod (7) is connected with the driving piece (6) and is driven by the driving piece (6) to rotate; and

the driving frame (8) is connected to the screw rod (7) in a threaded manner; one end of the buffer spring (4) is connected with the driving frame (8);

the buffer spring (4) and the compression spring (5) are sleeved on the screw rod (7).

3. The automatic presser foot lifting mechanism of claim 2, wherein: the presser foot assembly (1) comprises:

a presser foot (9);

a pressure lever (10) connected to the presser foot (9); and

a guide block (11) which is arranged on a shell (21) of the sewing machine in a sliding way, and the pressure lever (10) is fixedly arranged on the guide block (11);

the buffer spring (4) and the compression spring (5) are arranged between the driving frame (8) and the guide block (11) in a pressing mode.

4. An automatic presser foot lifting mechanism according to claim 3, wherein: the guide block (11) is provided with a vertical fixing hole (12) for mounting the compression bar (10); one side of the guide block (11) is also provided with a transverse fixing hole (13), and the transverse fixing hole (13) is communicated with the vertical fixing hole (12); the tail end of the fastener (14) penetrates through the transverse fixing hole (13) to extend into the vertical fixing hole (12) and abut against the compression bar (10), so that the compression bar (10) is fixed on the guide block (11).

5. The automatic presser foot lifting mechanism of claim 4, wherein: the driving frame (8) is provided with a long slotted hole (15), the fastener (14) penetrates through the long slotted hole (15) and is arranged on the guide block (11), and when the driving frame (8) moves upwards and the fastener (14) abuts against the lower end part of the long slotted hole (15), the driving frame (8) drives the guide block (11) to move upwards.

6. An automatic presser foot lifting mechanism according to claim 3, wherein: a guide groove (16) is formed in the shell (21), a sliding block (17) is formed in one side of the guide block (11), the sliding block (17) is arranged in the guide groove (16), and two ends of the guide groove (16) are used for limiting the guide block (11) during up-down movement.

7. An automatic presser foot lifting mechanism according to claim 3, wherein: the presser foot assembly (1) further comprises:

a loop bar (18) fixedly arranged on the shell (21); one end of the loop bar (18) is positioned in the shell (21), and the other end of the loop bar extends to the outer side of the shell (21); the compression bar (10) is arranged in the loop bar (18) in a penetrating way.

8. An automatic presser foot lifting mechanism according to claim 3, wherein: a groove (19) is formed in the upper end of the compression bar (10), and the end of the screw rod (7) can extend into the groove (19).

9. An automatic presser foot lifting mechanism according to any one of claims 1 to 8, wherein: the elastic coefficient of the buffer spring (4) is smaller than that of the pressing spring (5).

10. An automatic presser foot lifting mechanism according to any one of claims 2 to 8, wherein: the driving piece (6) is a stepping motor, and the screw rod (7) is connected with the stepping motor through a coupler (20).