CN113235239B - Driving wheel for cutting thread and lifting presser foot, sewing machine and control method - Google Patents

Abstract

The invention belongs to the technical field of sewing machines, and particularly relates to a driving wheel for thread cutting and presser foot lifting, a sewing machine and a control method, the driving wheel comprises a driving wheel body, a lifting and pressing cam part and a thread cutting curved surface part are respectively arranged on the driving wheel body, a non-executed lifting and pressing stroke surface I and a executed lifting and pressing top idle stroke surface II are respectively arranged on two sides of the lifting and pressing cam part, a lifting and pressing process stroke surface I and a lifting and pressing process stroke surface II are arranged between the non-executed lifting and pressing stroke surface I and the executed lifting and pressing top idle stroke surface II, and the thread cutting curved surface part is provided with a non-executed thread cutting idle stroke surface I, a executed thread cutting top idle stroke surface II, a thread cutting process stroke surface I and a thread cutting process stroke surface II.

Description

Driving wheel for cutting thread and lifting presser foot, sewing machine and control method

Technical Field

The invention relates to the technical field of sewing machines, in particular to a driving wheel for cutting threads and lifting presser feet, a sewing machine and a control method.

Background

Along with the continuous improvement of the degree of automation of the sewing machine, the sewing machine is generally provided with an automatic thread trimming mechanism and an automatic presser foot lifting mechanism, so that the actions of automatically lifting the presser foot and automatically trimming the thread are respectively realized, the time is saved, the labor force is reduced, and the working efficiency is improved.

For example, chinese patent publication No. CN109537194A discloses a sewing machine and an automatic presser foot lifting and thread cutting control method.

Although the automatic thread cutting or presser foot lifting action can be realized through the rotation of the motor, the thread cutting and presser foot lifting mechanism cannot work simultaneously, and only the thread cutting or presser foot lifting mechanism can be controlled independently in one period.

Therefore, the existing overedger structure needs to be further improved.

Disclosure of Invention

The invention aims to provide a driving wheel for cutting threads and lifting presser feet, a sewing machine and a control method, and the problem of single function is solved through the structure of a driving wheel body with novel design.

The purpose of the invention is realized in the following way: a driving wheel for cutting thread and lifting presser foot comprises

The driving wheel body is respectively provided with a lifting and pressing cam part and a shearing curve part, two sides of the lifting and pressing cam part are respectively provided with an un-executed lifting and pressing pressure stroke surface I and an executed lifting and pressing top end idle stroke surface II, a lifting and pressing process stroke surface I and a lifting and pressing process stroke surface II are arranged between the un-executed lifting and pressing top end idle stroke surface I and the executed lifting and pressing top end idle stroke surface II, two sides of the shearing curve part are provided with an un-executed shearing line idle stroke surface I and an executed shearing top end idle stroke surface II, and a shearing line process stroke surface I and a shearing line process stroke surface II are arranged between the un-executed shearing line idle stroke surface I and the executed shearing top end idle stroke surface II;

The presser foot lifting connecting rod assembly is positioned on the side surface of the presser foot lifting cam part, is connected with the presser foot lifting assembly and is used for executing the presser foot lifting action;

the thread cutting connecting rod assembly is positioned on the side face of the thread cutting curved face part, is connected with the thread cutting assembly and is used for executing thread cutting actions;

The rotating area of the driving wheel body can be divided into a first adjusting area, a second adjusting area, a third adjusting area, a fourth adjusting area and a fifth adjusting area, and the first adjusting area, the second adjusting area, the third adjusting area, the fourth adjusting area and the fifth adjusting area form a continuous circular area;

The first non-executing lifting pressure air travel surface and the first thread cutting travel surface correspond to a first adjusting area;

the first stroke surface and the first idle stroke surface which do not execute trimming in the lifting and pressing process correspond to a second adjusting area;

the second lifting and pressing top end idle stroke surface and the second stroke surface in the thread cutting process correspond to a third adjusting area;

The stroke surface II in the lifting and pressing process and the idle stroke surface II at the top end of the executed trimming are corresponding to a fourth adjusting area;

the second executed lifting top idle stroke surface corresponds to a fifth adjusting area;

The driving wheel body is provided with an origin, the origin is the junction point of the first adjusting area and the second adjusting area, the junction point between the first adjusting area and the fourth adjusting area is marked as a junction point I, the junction point between the fourth adjusting area and the third adjusting area is marked as a junction point II, the junction point between the third adjusting area and the fifth adjusting area is marked as a junction point III, and the junction point between the fifth adjusting area and the second adjusting area is marked as a junction point IV;

the driving wheel body can rotate by 360 degrees, the angle of the first junction point relative to the original point is 90 degrees+/-15 degrees, the angle of the second junction point relative to the original point is 180 degrees+/-15 degrees, the angle of the third junction point relative to the original point is 270 degrees+/-15 degrees, and the angle of the fourth junction point relative to the original point is 280 degrees+/-15 degrees;

when the driving wheel body rotates clockwise to the first adjusting area, the presser foot lifting connecting rod assembly and the thread cutting connecting rod assembly are positioned in the first adjusting area, the presser foot lifting assembly is in idle stroke contact, and the thread cutting assembly executes thread cutting action;

When the driving wheel body rotates anticlockwise to the second adjusting area, the presser foot lifting connecting rod assembly and the thread cutting connecting rod assembly are positioned in the first adjusting area, the thread cutting assemblies are in idle stroke contact, and the presser foot lifting assembly performs a presser foot lifting action;

when the driving wheel body rotates anticlockwise to the fifth adjusting area, the presser foot lifting connecting rod assembly is positioned in the fifth adjusting area, the presser foot lifting connecting rod assembly is lifted, and the thread cutting assembly can execute the presser foot lifting assembly in the third adjusting area to keep a lifted state through anticlockwise movement so as to execute thread cutting action;

The driving wheel body rotates clockwise to sequentially pass through the first adjusting area, the fourth adjusting area, the third adjusting area and the fifth adjusting area, the thread cutting assembly executes thread cutting action, the presser foot lifting assembly executes presser foot lifting action, and the presser foot lifting assembly resets clockwise after the actions are completed.

A sewing machine comprises a machine shell, wherein a motor is transversely arranged on one side of the machine shell, the output shaft of the motor is provided with a driving wheel body, a driving pin shaft which drives a thread cutting connecting rod assembly in a certain stroke is arranged in a thread cutting curved surface part, and the driving pin shaft is connected with the thread cutting connecting rod assembly.

Preferably, the presser foot lifting connecting rod assembly comprises a rotating shaft rotatably arranged in the machine shell, one end of the rotating shaft is provided with a middle lever, the upper end of the middle lever is positioned at one side of the presser foot lifting cam part, and the other end of the rotating shaft is connected with the presser foot lifting assembly.

Preferably, a driving block is arranged on the periphery of the rotating shaft, an arc-shaped groove is formed in the middle lever, a pushing block is formed at one end of the driving block, and the pushing block is arranged in the arc-shaped groove.

Preferably, a rotatable foot control lifting and pressing lever is arranged on the shell, one end of the foot control lifting and pressing lever is connected with the lower end of the middle lever through a pull rod, and the other end of the foot control lifting and pressing lever is connected with a foot control lifting and pressing assembly.

Preferably, a pushing part is formed at the upper end of the middle lever, and a rotatable rotating wheel is arranged on the pushing part.

Preferably, a reset torsion spring is arranged between the lower end of the middle lever and the casing.

Preferably, the wire cutting connecting rod assembly comprises a long rocker arm, the upper end of the long rocker arm is provided with the driving pin shaft, the middle part of the long rocker arm is hinged on the machine shell or the upper end of the long rocker arm is hinged on the machine body, the middle part of the long rocker arm is provided with the driving pin shaft, the lower end of the long rocker arm is hinged with a short rocker arm, the other end of the short rocker arm is hinged with a crank, and the other end of the crank is connected with the wire cutting assembly.

Preferably, the end part of the driving pin shaft is spherical; the lifting and pressing cam part is convexly arranged on the periphery of the driving wheel body; a plane bearing is arranged between the driving wheel body and the end face of the motor, and a limiting block is arranged at the outer end of the driving wheel body.

A thread cutting and presser foot lifting control method of a sewing machine comprises the following steps;

s1: starting the sewing machine, and initializing a motor by a controller to find an origin;

S2: when the driving wheel body is positioned at the original point position, the controller judges that the input signal is to cut lines alone or lift the presser foot, and then the presser foot is lifted after the line is cut or the line is cut and then the presser foot is lifted after the line is cut;

S3.1): when the controller judges that the input signal is single thread cutting, the driving wheel body rotates clockwise to the first adjusting area, so that the thread cutting connecting rod assembly passes through the first thread cutting process travel surface, the presser foot lifting connecting rod assembly passes through the first non-pressure lifting travel surface, the presser foot lifting assembly performs no action in idle stroke contact, the thread cutting assembly performs thread cutting action from the origin to the first boundary point, and after the thread cutting assembly reciprocates once, the driving wheel body rotates anticlockwise to reset to the origin;

S3.2): when the controller judges that the input signal is an independent presser foot lifting, the driving wheel body rotates anticlockwise to the second adjusting area, the presser foot lifting connecting rod assembly passes through the first stroke surface in the lifting process, the thread cutting connecting rod assembly passes through the first idle stroke surface without executing thread cutting, at the moment, the idle stroke contact of the thread cutting assembly does not execute action, the presser foot lifting assembly executes the presser foot lifting action from the origin to the junction point IV, and after the driving wheel body reciprocates once, the driving wheel body rotates clockwise to reset to the origin;

S3.3): when the controller judges that an input signal is to cut a wire when the presser foot is lifted, the driving wheel body rotates anticlockwise to a fifth adjusting area, the presser foot lifting connecting rod assembly is positioned in the fifth adjusting area, at the moment, the presser foot lifting assembly is lifted, the wire cutting assembly executes the wire cutting action in the third adjusting area through anticlockwise movement, the wire cutting assembly executes the wire cutting action from a third junction point to a second junction point, the wire cutting action is executed when the presser foot lifting assembly keeps a lifted state, the presser foot lifting assembly returns to the fifth adjusting area after being reciprocated once, and the wire cutting assembly can be manually controlled to repeatedly cut the wire through the controller under the condition that the presser foot lifting assembly keeps the lifted state;

S3.4): when the controller judges that the input signal is that the thread is cut and then the presser foot is continuously lifted, the driving wheel body clockwise executes the first half stroke of the thread cutting action from the original point to the first junction point, then continuously clockwise rotates, continuously executes the lifting state of the presser foot lifting action from the first junction point to the second junction point, then continuously clockwise rotates, continuously executes the second half stroke of the thread cutting action from the second junction point to the third junction point, until the continuous operation reaches the fifth adjusting area, and the presser foot is lifted to keep the lifting state of the fifth adjusting area after the thread cutting execution is finished;

S3.5): when the controller judges that the input signal is that the trimming is finished and then the presser foot is lifted, the step S3.1 is executed first, and then the step S3.2 is executed consecutively.

Compared with the prior art, the invention has the following outstanding and beneficial technical effects:

1. According to the invention, through the design of the driving wheel, the motion of the presser foot lifting assembly and the thread cutting assembly can be synchronously or asynchronously controlled by one motor, and the two motions can be completed by 360 DEG operation, so that the structure is simple, the manufacturing cost is reduced, the efficiency is high, the thread cutting motion can be realized in the state of lifting the presser foot, and the problem that the thread cutting can not be performed while lifting the presser foot in the prior motor driving technology is solved.

2. The invention can ensure the motor to operate at any angle through the design that the driving wheel can operate at 360 degrees, and can not cause the problems of various strong abrasion, breakage or damage caused by the blocking and the impact of the mechanical hinge.

Drawings

Fig. 1 is a schematic structural view of a driving wheel body.

Fig. 2 is a schematic structural view of a curved surface of a shear line on a driving wheel body.

Fig. 3 is a schematic structural view of a lifting cam portion on a driving wheel body.

Fig. 4 is a schematic structural view of the overedger.

Fig. 5 is a schematic structural view of the driving wheel, the presser foot lifting connecting rod assembly and the wire cutting connecting rod assembly.

Fig. 6 is a schematic diagram II of the structure of the driving wheel, the presser foot lifting connecting rod assembly and the wire cutting connecting rod assembly.

Fig. 7 is a schematic view of the structure of the driving wheel, the intermediate lever and the long rocker arm.

Fig. 8 is a schematic structural view of the driving wheel, the presser foot lifting connecting rod assembly and the thread cutting connecting rod assembly.

Fig. 9 is a logic diagram of a control method in the present invention.

Reference numerals: 1-a shell; 2-an electric motor; 3-reset torsion springs; 4-lifting the presser foot assembly; 5-a wire cutting assembly; 6-foot control lifting and pressing lever; 7-a pull rod; 8-plane bearings; 9-limiting blocks; 10-a driving wheel body;

12-cutting curved surfaces; 13-a spring; 14-lifting and pressing the cam part; 20-lifting a presser foot connecting rod assembly; 21-a rotation shaft; 22-an intermediate lever; 23-a drive block; 30-a wire cutting link assembly; 31-driving a pin shaft;

32-long rocker arms; 33-a rocker arm fixing plate; 34-short rocker arms; 35-crank

221-Arc grooves; 222-pushing part; 223-turning wheel; 231-pushing block;

121-executing no thread trimming idle stroke surface I; 122-executed trimming top idle stroke surface two; 123-stroke surface I of the thread cutting process;

124-stroke surface II in the thread cutting process;

141-non-executing the lift-press travel surface one; 142-the lifting and pressing of the top idle stroke surface II is executed; 143-a first stroke surface in the lifting and pressing process;

144-a stroke surface II in the lifting and pressing process;

a1-a first regulatory region; a2-a second regulatory region; a3-a third regulatory region; a4-fourth regulatory region;

a5-a fifth regulatory region;

p 0-origin; p 1-interface point one; p 2-junction two; p 3-junction three; p 4-junction four.

Detailed Description

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

With reference to FIGS. 1,2 and 3, a drive wheel for cutting wire and lifting presser foot comprises

The driving wheel body 10 is respectively provided with a lifting and pressing cam part 14 and a thread cutting curved surface part 12, two sides of the lifting and pressing cam part 14 are respectively provided with a non-executed lifting and pressing air travel surface I141 and an executed lifting and pressing top end air travel surface II 142, a lifting and pressing process travel surface I143 and a lifting and pressing process travel surface II 144 are arranged between the non-executed lifting and pressing top end air travel surface I141 and the executed lifting and pressing top end air travel surface II 142, two sides of the thread cutting curved surface part 12 are provided with a non-executed thread cutting air travel surface I121 and an executed thread cutting top end air travel surface II 122, and a thread cutting process travel surface I123 and a thread cutting process travel surface II 124 are arranged between the non-executed thread cutting air travel surface I121 and the executed thread cutting top end air travel surface II 122;

The presser foot lifting connecting rod assembly 20 is positioned on the side surface of the presser foot lifting cam part 14, and the presser foot lifting connecting rod assembly 20 is connected with the presser foot lifting assembly 4 and is used for executing the presser foot lifting action;

The thread cutting connecting rod assembly 30 is positioned on the side surface of the thread cutting curved surface part 12, and the thread cutting connecting rod assembly 30 is connected with the thread cutting assembly 5 and is used for executing thread cutting actions;

The rotation area of the driving wheel body 10 can be divided into a first adjusting area A1, a second adjusting area A2, a third adjusting area A3, a fourth adjusting area A4 and a fifth adjusting area A5, wherein the first adjusting area A1, the second adjusting area A2, the third adjusting area A3, the fourth adjusting area A4 and the fifth adjusting area A5 form a continuous 360-degree circular area;

The non-lifting pressure stroke surface 141 and the lifting pressure top idle stroke surface 142 correspond to the lifting or lowering state of the lifting foot assembly 4;

the first lifting and pressing process travel surface 143 and the second lifting and pressing process travel surface 144 respectively correspond to the lifting or putting down process of the lifting and pressing foot assembly 4;

when the first non-performed thread cutting idle stroke surface 121 reaches the second performed thread cutting top idle stroke surface 122, the first thread cutting process stroke surface 123 and the second thread cutting process stroke surface 124 will be passed, so that the thread cutting assembly 5 performs thread cutting action.

The non-execution lifting pressure air stroke surface one 141 and the trimming process stroke surface one 123 correspond to the first adjustment area A1;

the lifting and pressing process stroke surface one 143 and the non-executing thread cutting idle stroke surface one 121 correspond to a second adjusting area A2;

The second lifting and pressing top idle stroke surface 142 and the second thread cutting stroke surface 124 correspond to a third adjusting area A3;

The second stroke surface 144 of the lifting and pressing process and the second idle stroke surface 122 of the top end of the executed trimming correspond to a fourth adjusting area A4;

the second end idle stroke surface 142 on which the lifting has been performed corresponds to the fifth adjustment area A5;

the driving wheel body 10 is provided with an origin p0, the origin p0 is the junction point of the first adjusting area A1 and the second adjusting area A2, the junction point between the first adjusting area A1 and the fourth adjusting area A4 is marked as a junction point p1, the junction point between the fourth adjusting area A4 and the third adjusting area A3 is marked as a junction point p2, the junction point between the third adjusting area A3 and the fifth adjusting area A5 is marked as a junction point three p3, and the junction point between the fifth adjusting area A5 and the second adjusting area A2 is marked as a junction point four p4;

The driving wheel body 10 can rotate 360 degrees without dead points to solve the problem that mechanical parts of a motor are stranded due to abnormal work, and the origin positioning is realized through programming of a system controller, clockwise and anticlockwise rotation,

The angle of the first boundary point p1 relative to the original point p0 is 90 degrees+/-15 degrees, the angle of the second boundary point p2 relative to the original point p0 is 180 degrees+/-15 degrees, the angle of the third boundary point p3 relative to the original point p0 is 270 degrees+/-15 degrees, the angle of the fourth boundary point p4 relative to the original point p0 is 280 degrees+/-15 degrees, and the angle range of each boundary point can be changed and can be adjusted according to actual conditions.

In the device, the adopted specific scheme is that the angle of the first junction point p1 relative to the original point p0 is 85 degrees, the angle of the second junction point p2 relative to the original point p0 is 195 degrees, the angle of the third junction point p3 relative to the original point p0 is 280 degrees, and the angle of the fourth junction point p4 relative to the original point p0 is 290 degrees.

The thread trimming and presser foot lifting control method of the sewing machine comprises the following steps;

s1: starting the sewing machine, and initializing a motor by a controller to find an origin p0;

s2: when the driving wheel body 10 is positioned at the origin p0, the controller judges that the input signal is

S3.1 separate trimming

Or S3.2 lifting the presser foot alone

Or S3.3 trimming when lifting the presser foot

Or S3.4 continuously executing the presser foot lifting after trimming

Or S3.5, after trimming is completed, the presser foot is lifted;

S3.1) the method for independently executing the thread cutting is as follows:

When the controller judges that the input signal is single thread cutting, the driving wheel body 10 rotates clockwise to the first adjusting area A1, so that the thread cutting connecting rod assembly 30 passes through the thread cutting process travel surface I123, the presser foot lifting connecting rod assembly 20 passes through the non-executed pressure lifting travel surface I141, the idle stroke contact of the presser foot lifting assembly 4 does not execute action, the thread cutting assembly 5 executes thread cutting action from the origin p0 to the junction point I p1, and after one reciprocation, the driving wheel body 10 rotates anticlockwise to reset to the origin p0;

s3.2) the method for independently executing the presser foot lifting is as follows:

When the controller judges that the input signal is a single presser foot lifting, the driving wheel body 10 rotates anticlockwise to the second adjusting area A2, the presser foot lifting connecting rod assembly 20 passes through the first stroke surface 143 in the lifting process, the thread cutting connecting rod assembly 30 passes through the first idle stroke surface 121 without executing thread cutting, at the moment, the idle stroke contact of the thread cutting assembly 5 does not execute action, the presser foot lifting assembly 4 executes the presser foot lifting action from the origin point p0 to the four boundary points p4, and after the driving wheel body 10 rotates clockwise to reset to the origin point p0 after one reciprocation;

S3.3) the method for trimming when the presser foot is kept in a lifted state after the presser foot is lifted comprises the following steps:

When the controller judges that an input signal is to cut a wire when the presser foot is lifted, the driving wheel body 10 rotates anticlockwise to the fifth adjusting area A5, the presser foot lifting connecting rod assembly 20 is positioned in the fifth adjusting area A5, at the moment, the presser foot lifting assembly 4 is lifted, the wire cutting assembly 5 executes the wire cutting action in the third adjusting area A3 through anticlockwise movement, the wire cutting assembly 5 executes the wire cutting action from the junction point three p3 to the junction point two p2, the presser foot lifting assembly 4 executes the wire cutting action when keeping the lifted state, and returns to the fifth adjusting area A5 after reciprocating once, and the wire cutting assembly 5 can be manually controlled to repeatedly cut the wire through the controller when the presser foot lifting assembly 4 keeps the lifted state;

s3.4), the method for continuously executing the action of lifting the presser foot after trimming is as follows:

the driving wheel body 10 rotates clockwise to sequentially pass through the first adjusting area A1, the fourth adjusting area A4, the third adjusting area A3 and the fifth adjusting area A5, the thread cutting assembly 5 executes thread cutting action, the continuous presser foot lifting assembly 4 executes presser foot lifting action,

That is, the thread cutting and the presser foot lifting actions are completed within one circle of operation of the driving wheel body 10,

When the controller judges that the input signal is that the thread is cut and then the presser foot is continuously lifted, the driving wheel body 10 clockwise executes the first half stroke of the thread cutting action from the original point p0 to the first junction point p1, then continues clockwise rotation, continuously executes the lifted state of the thread lifting action from the first junction point p1 to the second junction point p2, then continues clockwise rotation, continuously executes the second half stroke of the thread cutting action from the second junction point p2 to the third junction point p3 until the thread cutting action continuously runs to the region of the fifth adjusting region A5, and the presser foot is lifted to keep the lifted state of the region of the fifth adjusting region A5 after the thread cutting action is finished;

after the above actions are completed, the presser foot lifting assembly is rotated clockwise to put down the presser foot until the reset origin p0 is reached. Realize 360 degrees of rotation to execute the actions of trimming and lifting the presser foot;

S3.5), the method for executing the presser foot lifting after the trimming is completed is as follows:

when the controller judges that the input signal is that the trimming is finished and then the presser foot is lifted, the step S3.1 is executed first, and then the step S3.2 is executed consecutively.

In the production and sewing application, different methods can be used for operation corresponding to different production process technical requirements, and various auxiliary functions are realized.

The driving wheel body 10 in the invention can independently control the action of the thread cutting assembly 5, has a simple structure, reduces the equipment cost, is convenient and practical, can execute the thread cutting action through an electric control when the presser foot is lifted and does not act, can execute the thread cutting action through the electric control when the presser foot is lifted and does not act, or can control the action of the thread cutting mechanism through a manual button to cut the thread manually, the motor is a closed loop stepping motor with an origin, and the absolute origin p0 position of the encoder is automatically found when the motor is started

Referring to fig. 4 to 7, a sewing machine includes a casing 1, a motor 2 is transversely disposed on one side of the casing 1, the driving wheel body 10 is disposed on an output shaft of the motor 2, a driving pin 31 for driving a thread cutting link assembly 30 in a certain stroke is disposed in a thread cutting curved surface portion 12, and the driving pin 31 is connected with the thread cutting link assembly 30.

According to the invention, through the design of the driving wheel body 10, the driving wheel body 10 can rotate clockwise or anticlockwise by 360 degrees to respectively execute synchronous or asynchronous thread trimming and presser foot lifting work, one motor 2 can respectively control the actions of the presser foot lifting assembly 4 and the thread trimming assembly 5 to finish two actions, the structure is simple, the equipment cost is reduced, the device is convenient and practical, and the thread trimming action can be executed while the presser foot lifting action is executed, so that the device is convenient to use.

The specific structure of the presser foot lifting link assembly 20 will be further described, the presser foot lifting link assembly 20 includes a rotating shaft 21 rotatably disposed in the casing 1, an intermediate lever 22 is mounted at one end of the rotating shaft 21, the upper end of the intermediate lever 22 is located at one side of the presser foot lifting cam portion 14, the intermediate lever 22 will be pushed and driven to rotate when the driving wheel body 10 rotates, and the other end of the rotating shaft 21 is connected with the presser foot lifting assembly 4, so as to drive the presser foot lifting assembly 4 to act.

The driving block 23 is installed on the periphery of the rotating shaft 21, the arc-shaped groove 221 is formed in the middle lever 22, the pushing block 231 is formed at one end of the driving block 23, the pushing block 231 is arranged in the arc-shaped groove 221, and in the actual working process, when the middle lever 22 rotates, the driving block 23 is driven to rotate through the cooperation of the arc-shaped groove 221 and the pushing block 231, and meanwhile the rotating shaft 21 is driven to rotate.

Be provided with rotatable foot control on casing 1 and lift and press lever 6, the foot control is lifted and is pressed the one end of lever 6 and is connected with the lower extreme of middle lever 22 through pull rod 7, and the other end of lever 6 is lifted and is pressed the subassembly to be connected with the foot control, and in actual working process, lift the clamp plate on the sewing machine through the foot control, will lift and press the subassembly through the foot control and drive the foot control and lift and press lever 6 rotation to lift middle lever 22 rotation in the presser foot link assembly 20 through pull rod 7 drive, thereby carry out the foot and lift the presser foot action.

The current market is generally structured as follows: the presser foot lifting and thread trimming cannot work simultaneously, but the presser foot lifting and thread trimming device is arranged in a separated structure between the presser foot lifting connecting rod assembly 20 and the driving wheel body 10, so that the presser foot lifting and thread trimming device can work simultaneously, the single-step feeding presser foot lifting and thread trimming device can be controlled by a stepping motor or can be controlled simultaneously with a traditional foot chain, when the presser foot is lifted by the foot chain, a button can be operated simultaneously to perform stepping thread trimming, and the presser foot lifting and thread trimming of the foot chain can be executed simultaneously when the thread trimming is performed, but the existing single-step thread trimming device cannot realize the functions of the invention.

The upper end of the intermediate lever 22 is formed with a pushing part 222, the pushing part 222 is provided with a rotatable rotating wheel 223, the rotating wheel 223 is used for contacting with the lifting cam part 14, so that friction force can be reduced, abrasion is reduced, and service life is prolonged.

A reset torsion spring 3 is arranged between the lower end of the middle lever 22 and the casing 1, and the reset torsion spring 3 is used for resetting the middle lever 22.

Next, a specific structure of the wire cutting link assembly 30 will be further described, the wire cutting link assembly 30 includes a long rocker arm 32, the upper end of the long rocker arm 32 is provided with the driving pin shaft 31, the middle part of the long rocker arm 32 is hinged with a rocker arm fixing plate 33, the other end of the rocker arm fixing plate 33 is connected with the casing 1, referring to fig. 8 specifically, the structure of the long rocker arm 32 may also be: the upper end of the long rocker arm 32 is hinged on the machine body, a driving pin shaft 31 is arranged in the middle of the long rocker arm 32, a short rocker arm 34 is hinged at the lower end of the long rocker arm 32, the other end of the short rocker arm 34 is connected with a wire cutting assembly 5, when the driving pin shaft 31 passes through the wire cutting curved surface portion 12, the long rocker arm 32 is pulled, the scissors assembly 5 is pulled to move through the short rocker arm 34, and when the driving pin shaft 31 passes through the wire cutting curved surface portion 12, the long rocker arm 32 is driven to rotate, and the scissors assembly 5 is driven to move through the short rocker arm 34.

The end of the driving pin 31 is spherical so that the end slides in the shear curved surface portion 12.

The curved line cutting part 12 is formed on one side surface of the driving wheel body 10, a driving groove is formed in the driving wheel body 10, and the curved line cutting part 12 is formed on the side wall of the driving groove.

The wire cutting connecting rod assembly 30 is further provided with a spring 13 for resetting the wire cutting connecting rod assembly, the spring comprises a tension spring or a torsion spring, and the like, and when only the wire cutting curved surface portion 12 unilaterally pushes the wire cutting assembly 5, the resetting of the wire cutting assembly 5 is reset under the action of the spring 13.

The plane bearing 8 is arranged between the driving wheel body 10 and the end face of the motor 2, so that the stability of the driving wheel body 10 during rotation can be improved, the limiting block 9 is arranged at the outer end of the driving wheel body 10, the moving position of the driving pin shaft 31 can be limited, and the position deviation of the driving pin shaft 31 is prevented from being separated from the driving wheel body 10.

The foregoing has shown and described the basic principles and main features of the present invention and the advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (10)

1. A drive wheel for cutting lines and lifting presser feet is characterized by comprising

The driving wheel body (10), the driving wheel body (10) is respectively provided with a lifting and pressing cam part (14) and a shearing curve surface part (12), two sides of the lifting and pressing cam part (14) are respectively provided with a non-executed lifting and pressing top idle stroke surface (141) and a executed lifting and pressing top idle stroke surface (142), a lifting and pressing process stroke surface (143) and a lifting and pressing process stroke surface (144) are arranged between the non-executed lifting and pressing top idle stroke surface (141) and the executed lifting and pressing top idle stroke surface (142), two sides of the shearing curve surface part (12) are provided with a non-executed shearing idle stroke surface (121) and a executed shearing top idle stroke surface (122), and a shearing process stroke surface (123) and a shearing process surface (124) are arranged between the non-executed shearing idle stroke surface (121) and the executed shearing top idle stroke surface (122);

The presser foot lifting connecting rod assembly (20) is positioned on the side surface of the presser foot lifting cam part (14), and the presser foot lifting connecting rod assembly (20) is connected with the presser foot lifting assembly (4) and is used for executing the presser foot lifting action;

the thread cutting connecting rod assembly (30) is positioned on the side face of the thread cutting curved face part (12), and the thread cutting connecting rod assembly (30) is connected with the thread cutting assembly (5) and is used for executing thread cutting actions;

The rotating area of the driving wheel body (10) can be divided into a first adjusting area (A1), a second adjusting area (A2), a third adjusting area (A3), a fourth adjusting area (A4) and a fifth adjusting area (A5), and the first adjusting area (A1), the second adjusting area (A2), the third adjusting area (A3), the fourth adjusting area (A4) and the fifth adjusting area (A5) form a continuous circular area;

the non-execution lifting pressure air travel surface one (141) and the thread cutting process travel surface one (123) correspond to a first adjusting area (A1);

The first lifting and pressing process stroke surface (143) and the first non-cutting idle stroke surface (121) correspond to a second adjusting area (A2);

the second lifting and pressing top end idle stroke surface (142) and the second thread cutting stroke surface (124) correspond to a third adjusting area (A3);

The second lifting and pressing process stroke surface (144) and the second executed thread cutting top idle stroke surface (122) correspond to a fourth adjusting area (A4);

The second (142) of the top idle stroke surface which has been lifted corresponds to the fifth adjusting area (A5);

an origin (p 0) is arranged on the driving wheel body (10), the origin (p 0) is the junction point of the first adjusting area (A1) and the second adjusting area (A2), the junction point between the first adjusting area (A1) and the fourth adjusting area (A4) is marked as a junction point I (p 1), the junction point between the fourth adjusting area (A4) and the third adjusting area (A3) is marked as a junction point II (p 2), the junction point between the third adjusting area (A3) and the fifth adjusting area (A5) is marked as a junction point III (p 3), and the junction point between the fifth adjusting area (A5) and the second adjusting area (A2) is marked as a junction point IV (p 4);

The driving wheel body (10) can rotate by 360 degrees, the angle of a first boundary point (p 1) relative to an original point (p 0) is 90 degrees+/-15 degrees, the angle of a second boundary point (p 2) relative to the original point (p 0) is 180 degrees+/-15 degrees, the angle of a third boundary point (p 3) relative to the original point (p 0) is 270 degrees+/-15 degrees, and the angle of a fourth boundary point (p 4) relative to the original point (p 0) is 280 degrees+/-15 degrees.

2. The sewing machine is characterized by comprising the driving wheel for thread cutting and presser foot lifting according to claim 1, and comprises a machine shell (1), wherein a motor (2) is transversely arranged on one side of the machine shell (1), the driving wheel body (10) is arranged on an output shaft of the motor (2), a driving pin (31) for driving a thread cutting connecting rod assembly (30) in a certain stroke is arranged in a thread cutting curved surface portion (12), and the driving pin (31) is connected with the thread cutting connecting rod assembly (30).

3. A sewing machine as defined in claim 2, wherein: the wire cutting connecting rod assembly (30) comprises a long rocker arm (32), the upper end of the long rocker arm (32) is provided with the driving pin shaft (31), the middle part of the long rocker arm (32) is hinged on the machine shell (1) or the upper end of the long rocker arm (32) is hinged on the machine body, the middle part of the long rocker arm (32) is provided with the driving pin shaft (31), the lower end of the long rocker arm (32) is hinged with a short rocker arm (34), the other end of the short rocker arm (34) is hinged with a crank (35), and the other end of the crank (35) is connected with the wire cutting assembly (5).

4. A sewing machine as defined in claim 2, wherein: the end part of the driving pin shaft (31) is spherical; the lifting and pressing cam part (14) is convexly arranged on the periphery of the driving wheel body (10); a plane bearing (8) is arranged between the driving wheel body (10) and the end face of the motor (2), and a limiting block (9) is arranged at the outer end of the driving wheel body (10).

5. A sewing machine as defined in claim 2, wherein: the presser foot lifting connecting rod assembly (20) comprises a rotating shaft (21) rotatably arranged in the machine shell (1), one end of the rotating shaft (21) is provided with a middle lever (22), the upper end of the middle lever (22) is positioned on one side of the presser foot lifting cam part (14), and the other end of the rotating shaft (21) is connected with the presser foot lifting assembly (4).

6. A sewing machine as defined in claim 5, wherein: the driving block (23) is arranged on the periphery of the rotating shaft (21), the middle lever (22) is provided with an arc-shaped groove (221), one end of the driving block (23) is provided with a pushing block (231), and the pushing block (231) is arranged in the arc-shaped groove (221).

7. A sewing machine as defined in claim 5, wherein: the machine shell (1) is provided with a rotatable foot control lifting and pressing lever (6), one end of the foot control lifting and pressing lever (6) is connected with the lower end of the middle lever (22) through a pull rod (7), and the other end of the foot control lifting and pressing lever (6) is connected with a foot control lifting and pressing assembly.

8. A sewing machine as defined in claim 5, wherein: the upper end of the middle lever (22) is provided with a pushing part (222), and the pushing part (222) is provided with a rotatable rotating wheel (223).

9. A sewing machine as defined in claim 5, wherein: a reset torsion spring (3) is arranged between the lower end of the middle lever (22) and the casing (1).

10. A thread cutting and presser foot lifting control method for a sewing machine, characterized by having the driving wheel for thread cutting and presser foot lifting according to claim 1, comprising the steps of;

s1: starting the sewing machine, and initializing a motor by a controller to find an origin (p 0);

s2: when the driving wheel body (10) is positioned at the original point (p 0), the controller judges that the input signal is single thread cutting or single presser foot lifting or presser foot lifting, thread cutting is carried out, then the presser foot lifting is carried out after continuous execution of thread cutting or thread cutting is finished, and then the presser foot lifting is carried out;

S3.1): when the controller judges that an input signal is single thread cutting, the driving wheel body (10) rotates clockwise to a first adjusting area (A1), so that the thread cutting connecting rod assembly (30) passes through a thread cutting process travel surface I (123), the presser foot lifting connecting rod assembly (20) passes through an unexecuted pressure lifting travel surface I (141), the presser foot lifting assembly (4) performs no action in idle stroke contact, the thread cutting assembly (5) performs thread cutting action from an origin point (p 0) to a junction point I (p 1), and after one reciprocation, the driving wheel body (10) rotates anticlockwise to return to the origin point (p 0);

s3.2): when the controller judges that an input signal is a single presser foot lifting, the driving wheel body (10) rotates anticlockwise to the second adjusting area (A2), the presser foot lifting connecting rod assembly (20) passes through a first stroke surface (143) in the lifting and pressing process, the thread cutting connecting rod assembly (30) passes through a first idle stroke surface (121) without executing thread cutting, at the moment, the thread cutting assembly (5) does not execute an idle stroke contact action, the presser foot lifting assembly (4) executes the presser foot lifting action from an origin (p 0) to a junction point four (p 4), and after one reciprocation, the driving wheel body (10) rotates clockwise to reset to the origin (p 0);

S3.3): when the controller judges that an input signal is to lift the presser foot and cut a line, when the driving wheel body (10) rotates anticlockwise to the fifth adjusting area (A5), the presser foot lifting connecting rod assembly (20) is positioned in the fifth adjusting area (A5), at the moment, the presser foot lifting assembly (4) is lifted, the line cutting assembly (5) executes the line cutting action in the third adjusting area (A3) through anticlockwise movement, so that the line cutting assembly (5) executes the line cutting action from the junction point III (p 3) to the junction point II (p 2), the line cutting action is executed when the presser foot lifting assembly (4) keeps the lifted state, the line cutting action is executed after the presser foot lifting assembly returns to the fifth adjusting area (A5) after the presser foot lifting assembly (4) keeps the lifted state, and the line cutting assembly (5) can be controlled to repeatedly cut a line through the controller manually;

S3.4): when the controller judges that the input signal is that the presser foot is continuously lifted after trimming, the driving wheel body 10 clockwise executes a first half stroke of the trimming action from an original point (p 0) to a junction point I (p 1), then continues clockwise rotation, continuously executes a lifted state of the presser foot lifting action from the junction point I (p 1) to a junction point II (p 2), then continues clockwise rotation, continuously executes a second half stroke of the trimming action from the junction point II (p 2) to a junction point III (p 3), until the driving wheel body continuously runs to a fifth adjusting area (A5), and the presser foot is lifted after trimming execution is finished to maintain a lifted state of the fifth adjusting area (A5);

S3.5): when the controller judges that the input signal is that the trimming is finished and then the presser foot is lifted, the step S3.1 is executed first, and then the step S3.2 is executed consecutively.