CN206783952U - The driving of sewing machine and thread cutting mechanism - Google Patents

Abstract

The utility model discloses a kind of driving of sewing machine and thread cutting mechanism, including drive mechanism and thread cutting mechanism；The drive mechanism includes power transmission shaft and drive shaft, and trimming driving cam crank assemblies are fixedly installed in drive shaft；The thread cutting mechanism includes trimming drive shaft, and trimming drive shaft is fixedly connected with trimming driving cam crank assemblies；The rotation of trimming driving cam crank assemblies can drive trimming drive shaft turns, and the rotation of trimming drive shaft drives trimming crank-swinging；The driving knife connecting rod that swings by of trimming crank drives driving knife group to rotate forward；At the same time, swing by secondary moving knife swing rod and the secondary moving knife connecting rod of trimming crank drive secondary movable cutter set to rotate backward, and driving knife is engaged with secondary moving knife, are acted so as to complete trimming.The control of the utility model trimming is accurate, and trimming biting point is stable, and trimming the end of a thread is short, without manually subtracting the end of a thread so as to reduce cost.

Description

Driving and thread trimming mechanism of sewing machine

technical field

The utility model relates to an accessory of a sewing machine, in particular to a driving and thread trimming mechanism of the sewing machine.

Background technique

With the increasing automation of sewing machines, many operations that previously required manual work have been automated, such as automatic thread trimming in sewing machines. The thread trimming device generally includes a driving mechanism, a transmission mechanism and a thread trimming mechanism. The driving mechanism generally adopts an electromagnet or a cylinder, and the thread trimming mechanism and the driving mechanism are connected by a transmission mechanism. The existing transmission mechanism has a complex structure, poor control accuracy, and the thread trimming mechanism is unstable in trimming the thread, and the length of the thread end is different, resulting in poor sewing quality and the need to increase the process of manual trimming of the thread end.

For example, the Chinese utility model patent document ZL94112770.2 discloses a thread trimming control device for a sewing machine. The thread trimming transmission mechanism includes a thread trimming cam, a thread trimming cam arm, a thread trimming link structure connected with The drive transmission structures such as the thread trimming arm of the present invention, the thread trimming connecting rod structure and the drive transmission structure are too complicated, there are many structural parts, the transmission efficiency is low, and the cost is high.

Contents of the invention

The technical problem to be solved by the utility model is to provide a sewing machine driving and thread trimming mechanism, which can solve the above problems more simply, quickly and with high reliability.

In order to solve the above-mentioned technical problems, the technical solution of the driving of the sewing machine of the present invention and the thread trimming mechanism is:

It includes a drive mechanism and a thread trimmer; the drive mechanism includes a drive shaft 1 and a drive shaft 13, a drive cam 2 is fixedly arranged on the drive shaft 1, and a first cam surface 2a and a second cam surface 2b are formed on the drive cam 2; The drive shaft 13 is fixedly provided with a thread trimming driving cam crank assembly 3, and the thread trimming driving cam crank assembly 3 is provided with a roller 3a, a reset pin 3b and a slider 3c; The first cam surface 2a of the cam 2 is corresponding; under the thread trimming state, the driving shaft 13 rotates under the action of the driving source, which can drive the thread trimming driving cam crank assembly 3 and the roller 3a on it to rotate, so that the roller 3a is in the Roll on the first cam surface 2a, thereby driving the transmission shaft 1 to rotate; the reset pin 3b of the thread trimming driving cam crank assembly 3 corresponds to the second cam surface 2b of the driving cam 2; when the thread trimming is completed, the second cam surface 2b and When the reset pin 3b touches, the thread trimming drive cam assembly 3 can be forcibly reset; the thread trimming mechanism includes a thread trimming drive shaft 5, which is fixedly connected to the thread trimming drive cam crank assembly 3; the thread trimming drive cam crank assembly The rotation of 3 can drive the thread trimming drive shaft 5 to rotate; the thread trimming drive shaft 5 is fixedly connected to one end of the thread trimming crank 7; the thread trimming crank 7 can swing around this end driven by the thread trimming drive shaft 5; the thread trimming crank 7 The middle section is provided with a first connection hole and a second connection hole; the thread trimmer crank 7 is connected to one end of the active knife connecting rod 10 through the first connecting hole, and the other end of the active knife connecting rod 10 is connected with the active knife group 11; the active knife group 11 is provided with driving knife 11a; Thread trimmer crank 7 connects the active end of auxiliary moving knife swing bar 8 through the second connecting hole; The driven end of auxiliary moving knife swing bar 8 is connected with an end of auxiliary moving knife connecting rod 9, The other end of the auxiliary movable knife connecting rod 9 is connected with the auxiliary movable knife group 12; the auxiliary movable knife group 12 is provided with an auxiliary movable knife 12a; The rotation of the cam crank assembly 3 can drive the thread trimmer drive shaft 5 to rotate, and the rotation of the thread trimmer drive shaft 5 drives the thread trimmer crank 7 to swing; the swing of the thread trimmer crank 7 drives the active knife group 11 to rotate forward through the active knife connecting rod 10; At the same time, the swing of the thread trimmer crank 7 drives the auxiliary movable knife group 12 to rotate in reverse through the auxiliary movable knife swing rod 8 and the auxiliary movable knife connecting rod 9, so that the active knife 11a and the auxiliary movable knife 12a are engaged, thereby completing the thread trimming action. .

One end of the drive shaft 13 is provided with a compression spring 4; when the drive shaft 13 rotates under the driving source, the compression spring 4 can store elastic potential energy, and the compression spring 4 can reset the drive shaft 13 after the drive source is disconnected .

A knife rest torsion spring 6 is housed on the described thread trimmer drive shaft 5; one end of the knife rest torsion spring 6 is connected to the thread trimmer crank 7, and the other end of the knife rest torsion spring 6 is connected to the thread trimmer drive shaft 5, and the knife rest torsion spring 6 is used for The thread cutter unit is reset.

The auxiliary movable knife swing bar 8 is provided with three holes, which are respectively opened at the active end of the auxiliary movable knife swing bar 8, the driven end of the auxiliary movable knife swing bar 8 and the middle part of the auxiliary movable knife swing bar 8. The three holes distributed in a triangle.

There is a clearance fit between the auxiliary movable knife swing lever 8 and the thread trimming drive shaft 5 .

The open slot of the thread trimming driving shaft 5 is matched with the slider 3c of the thread trimming driving cam crank assembly 3, and the thread trimming driving cam crank assembly 3 is fixedly connected to the thread trimming driving shaft 5 through the slider 3c.

The drive shaft 13 is arranged parallel to the transmission shaft 1 .

The thread cutting drive shaft 5 is arranged parallel to the drive shaft 13 .

The driving source is an electromagnet or a cylinder.

In the initial state, the roller 3a of the thread trimming driving cam crank assembly 3 is in a state of being staggered from the first cam surface 2a of the driving cam 2;

In the thread trimming state, the driving shaft 13 rotates under the action of the driving source, driving the thread trimming driving cam crank assembly 3 and the roller 3a on it to rotate, so that the ball 3a of the thread trimming driving cam crank assembly 3 and the first roller 3a of the driving cam 2 A cam surface 2a is in contact with each other, and the compression spring 4 is in a compressed state at the same time; the drive shaft 13 continues to rotate, so that the roller 3a rolls on the first cam surface 2a of the drive cam 2, driving the drive cam 2 to rotate, so that the drive shaft 1 Rotation; the rotation of the transmission shaft 1 drives the second cam surface 2b to rotate synchronously until the second cam surface 2b of the drive cam 2 contacts the reset pin 3b on the thread trimmer drive cam assembly 3; at the same time, the thread trimmer drive cam crank The rotation of the component 3 drives the thread trimmer drive shaft 5 to rotate, and the rotation of the thread trimmer drive shaft 5 drives the thread trimmer crank 7 to swing; the swing of the thread trimmer crank 7 drives the active knife group 11 to rotate forward through the active knife connecting rod 10; at the same time , the swing of the thread trimmer crank 7 drives the auxiliary movable knife group 12 to rotate in reverse through the auxiliary movable knife swing rod 8 and the auxiliary movable knife connecting rod 9, so that the active knife 11a and the auxiliary movable knife 12a are engaged, thereby completing the thread trimming action;

After the driving source is disconnected, the thread trimmer crank 7 resets under the action of the torsion spring 6 of the tool holder, so that the active knife 11a and the auxiliary movable knife 12a are reset; at the same time, the compression spring 4 makes the drive shaft 13 and the thread trimming drive cam assembly 3 reset.

The technical effect that the utility model can reach is:

The utility model has the advantages of simple and compact structure, convenient installation and maintenance, high reliability and low cost.

The utility model has precise thread trimming control, stable thread trimming occlusal points, short thread trimming thread ends, and no need to manually reduce the thread ends to reduce costs.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment, the utility model is described in further detail:

Fig. 1 is the three-dimensional schematic view that the driving and thread trimming mechanism of the sewing machine of the present invention are arranged in the casing;

Fig. 2 is the three-dimensional schematic view of the utility model;

Fig. 3 is a three-dimensional schematic diagram of another angle of the utility model;

Fig. 4 is an exploded schematic view of the linkage mechanism of the present invention.

Explanation of the reference signs in the figure:

1 is the transmission shaft, 2 is the driving cam,

3 is the thread trimmer drive cam crank assembly, 4 is the compression spring,

5 is the thread trimming drive shaft, 6 is the knife rest torsion spring,

7 is the thread trimmer crank, and 8 is the auxiliary moving knife swing bar,

9 is the auxiliary moving knife connecting rod, and 10 is the driving knife connecting rod,

11 is the active knife group, 12 is the auxiliary knife group,

13 is the drive shaft, 2a is the first cam surface,

2b is the second cam surface, 3a is the roller,

3b is a reset pin, 3c is a slider,

11a is the active knife, 12a is the auxiliary knife,

100 is the casing.

detailed description

In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution of the embodiment of the utility model will be clearly and completely described below in conjunction with the accompanying drawings of the embodiment of the utility model. Apparently, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the described embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work shall fall within the protection scope of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by those skilled in the art to which the present invention belongs. As used herein, "first", "second" and similar words do not imply any order, quantity or importance, but are used only to distinguish different components. "Comprising" and similar words mean that the elements or items appearing before the word include the elements or items listed after the word and their equivalents, and do not exclude other elements or items.

As shown in Figures 1 to 3, the driving and thread trimming mechanism of the sewing machine of the present utility model includes a driving mechanism and a thread trimming mechanism;

The drive mechanism includes a transmission shaft 1 and a drive shaft 13 arranged in the casing 100, and the drive shaft 13 is arranged in parallel with the transmission shaft 1; the drive shaft 13 can rotate under the action of the drive source; the drive source can be a straight line such as an electromagnet or a cylinder. driving device;

A driving cam 2 is fixedly arranged on the transmission shaft 1; a first cam surface 2a and a second cam surface 2b are formed on the driving cam 2;

The drive shaft 13 is fixedly provided with a trimming drive cam crank assembly 3; one end of the drive shaft 13 is provided with a compression spring 4; when the drive shaft 13 rotates under the drive of the drive source, the compression spring 4 can store elastic potential energy;

The thread trimming drive cam crank assembly 3 is provided with a roller 3a, a reset pin 3b and a slider 3c;

The roller 3a of the thread trimming driving cam crank assembly 3 corresponds to the first cam surface 2a of the driving cam 2; in the thread trimming state, the roller 3a rolls on the first cam surface 2a; the reset of the thread trimming driving cam crank assembly 3 The pin 3b corresponds to the second cam surface 2b of the driving cam 2; when the thread trimming is completed, the second cam surface 2b touches the reset pin 3b, so that the thread trimming driving cam assembly 3 can be forcibly reset.

The thread trimming mechanism includes a thread trimming drive shaft 5, which is arranged in parallel with the drive shaft 13; the thread trimming drive shaft 5 is mounted in the casing 100 through a bushing; the slider 3c of the thread trimming drive cam crank assembly 3 and the The opening groove of the thread trimming drive shaft 5 matches, and the thread trimming drive cam crank assembly 3 is fixedly connected to the thread trimming drive shaft 5 through the slider 3c; the rotation of the thread trimming drive cam crank assembly 3 can drive the thread trimming drive shaft 5 to swing;

As shown in Figure 4, the thread trimming drive shaft 5 is fixedly connected to one end of the thread trimming crank 7; the thread trimming crank 7 can swing around this end driven by the thread trimming drive shaft 5;

The middle section of the thread cutter crank 7 is provided with a first connecting hole and a second connecting hole;

The thread trimmer crank 7 is connected to one end of the active knife connecting rod 10 by a screw passing through the first connecting hole, and the other end of the active knife connecting rod 10 is connected to the active knife group 11; the active knife group 11 is provided with an active knife 11a;

The thread trimmer crank 7 is connected to the driving end of the auxiliary knife swing rod 8 through the screw passing through the second connecting hole; connected, the other end of the auxiliary movable knife connecting rod 9 is connected with the auxiliary movable knife group 12; the auxiliary movable knife group 12 is provided with an auxiliary movable knife 12a;

The middle part of the auxiliary knife swing rod 8 is sleeved on the thread trimming drive shaft 5;

The tool rest torsion spring 6 is installed on the thread trimming drive shaft 5; one end of the tool post torsion spring 6 is connected to the thread trimmer crank 7, and the other end of the tool post torsion spring 6 is connected to the thread trimming drive shaft 5, and the tool post torsion spring 6 is used for thread trimming Knife group reset.

There are three holes on the auxiliary knife swing bar 8, which are respectively opened on the active end of the auxiliary knife swing bar 8, the driven end of the auxiliary knife swing bar 8 and the middle part of the auxiliary knife swing bar 8, and the holes at one end The thread trimming crank 7 is fixedly connected by screws, the hole opened at the other end is hinged with the auxiliary knife connecting rod 9 through the axial screw, and the hole set in the middle section is set on the thread trimming drive shaft 5; the three holes are distributed in a triangle;

There is a clearance fit between the auxiliary knife swing lever 8 and the thread trimming drive shaft 5;

The working principle of the utility model is as follows:

In the initial state, the roller 3a of the thread trimmer drive cam crank assembly 3 is in a staggered state from the first cam surface 2a of the drive cam 2;

When the driving shaft 13 rotates under the action of the driving source, it drives the thread trimmer drive cam crank assembly 3 and the roller 3a on it to rotate, so that the ball 3a of the thread trimmer drive cam crank assembly 3 and the first cam surface 2a of the drive cam 2 are in contact with each other, and the compression spring 4 is in a compressed state at the same time;

The drive shaft 13 continues to rotate, so that the roller 3a rolls on the first cam surface 2a of the drive cam 2, driving the drive cam 2 to rotate, thereby making the transmission shaft 1 rotate; the rotation of the transmission shaft 1 drives the second cam surface 2b to rotate synchronously, Until the second cam surface 2b of the drive cam 2 contacts the reset pin 3b on the thread trimming drive cam assembly 3;

At the same time, the rotation of the thread-cutting drive cam crank assembly 3 drives the thread-cutting drive shaft 5 to rotate, and the rotation of the thread-cutting drive shaft 5 drives the thread-cutting crank 7 to swing; the swing of the thread-cutting crank 7 drives the active knife through the active knife connecting rod 10 Group 11 rotates in the forward direction; at the same time, the swing of thread trimmer crank 7 drives auxiliary moving knife group 12 to rotate reversely through auxiliary moving knife swing rod 8 and auxiliary moving knife connecting rod 9; due to the active knife group 11 and auxiliary moving knife group The rotation direction of 12 is opposite, so that the active knife 11a and the auxiliary movable knife 12a are engaged to complete the thread trimming action;

After the driving source is disconnected, the thread trimmer crank 7 resets under the action of the torsion spring 6 of the tool holder, so that the active knife 11a and the auxiliary movable knife 12a are reset; at the same time, the compression spring 4 makes the drive shaft 13 and the thread trimming drive cam assembly 3 reset.

Although the embodiments of the present invention have been described in detail above, it is obvious for those skilled in the art that various modifications and changes can be made to these embodiments. However, it should be understood that such modifications and changes belong to the scope and spirit of the present invention described in the claims. Moreover, the invention described herein is capable of other embodiments and of being practiced or carried out in various ways.

Claims (9)

1. A driving and thread trimming mechanism of a sewing machine, characterized in that: comprising a driving mechanism and a thread trimming mechanism; The drive mechanism includes a drive shaft (1) and a drive shaft (13), a drive cam (2) is fixedly arranged on the drive shaft (1), and a first cam surface (2a) and a second cam surface (2a) are formed on the drive cam (2). Cam surface (2b); the drive shaft (13) is fixed with a thread trimming driving cam crank assembly (3), and the thread trimming driving cam crank assembly (3) is provided with a roller (3a), a reset pin (3b) and a slide Block (3c); the roller (3a) of the thread trimming drive cam crank assembly (3) corresponds to the first cam surface (2a) of the drive cam (2); in the thread trimming state, the drive shaft (13) is at the drive source Under the action of the rotation, it can drive the thread trimming drive cam crank assembly (3) and the roller (3a) on it to rotate, so that the roller (3a) rolls on the first cam surface (2a), thereby driving the transmission shaft (1 ) rotation; the reset pin (3b) of the thread trimming driving cam crank assembly (3) corresponds to the second cam surface (2b) of the driving cam (2); when the thread trimming is completed, the second cam surface (2b) and the reset pin (3b) Touching can make the thread trimming drive cam assembly (3) reset forcibly; The thread trimming mechanism includes a thread trimming drive shaft (5), which is fixedly connected to the thread trimming drive cam crank assembly (3); the rotation of the thread trimming drive cam crank assembly (3) can drive the thread trimming drive shaft (5) Rotate; the thread trimming drive shaft (5) is fixedly connected to one end of the thread trimming crank (7); the thread trimming crank (7) can swing around this end driven by the thread trimming drive shaft (5); the thread trimming crank ( The middle section of 7) is provided with a first connection hole and a second connection hole; the thread trimming crank (7) is connected to one end of the driving knife connecting rod (10) through the first connecting hole, and the other end of the driving knife connecting rod (10) is connected to the driving knife connecting rod (10). The knife groups (11) are connected; the active knife group (11) is provided with a driving knife (11a); the thread trimmer crank (7) is connected to the active end of the auxiliary moving knife swing rod (8) through the second connection hole; the auxiliary moving knife The driven end of the swing rod (8) is connected with one end of the auxiliary movable knife connecting rod (9), and the other end of the auxiliary movable knife connecting rod (9) is connected with the auxiliary movable knife group (12); the auxiliary movable knife group (12) The auxiliary movable knife (12a) is arranged on the top; the middle part of the auxiliary movable knife swing rod (8) is sleeved on the thread trimming drive shaft (5); The rotation of the thread trimmer drive cam crank assembly (3) can drive the thread trimmer drive shaft (5) to rotate, and the rotation of the thread trimmer drive shaft (5) drives the thread trimmer crank (7) to swing; the swing of the thread trimmer crank (7) is driven by the active The knife connecting rod (10) drives the active knife group (11) to rotate forward; at the same time, the swing of the thread trimming crank (7) drives the auxiliary moving knife through the auxiliary moving knife swing rod (8) and the auxiliary moving knife connecting rod (9). The knife group (12) rotates in reverse to make the active knife (11a) engage with the auxiliary knife (12a), thereby completing the thread trimming action. 2. The driving and thread trimming mechanism of the sewing machine according to claim 1, characterized in that: one end of the driving shaft (13) is provided with a compression spring (4); when the driving shaft (13) is driven by the driving source While rotating, the compression spring (4) can store elastic potential energy, and the compression spring (4) can reset the drive shaft (13) after the driving source is disconnected. 3. The driving and thread trimming mechanism of the sewing machine according to claim 1 or 2, characterized in that: the thread trimming drive shaft (5) is equipped with a knife rest torsion spring (6); the knife rest torsion spring (6) One end is connected to the thread trimmer crank (7), the other end of the tool holder torsion spring (6) is connected to the thread trimmer drive shaft (5), and the tool holder torsion spring (6) is used for resetting the thread trimmer group. 4. The driving and thread trimming mechanism of the sewing machine according to claim 1, characterized in that: there are three holes on the auxiliary movable knife swing rod (8), respectively opened in the active part of the auxiliary movable knife swing rod (8). End, the driven end of the auxiliary moving knife swing bar (8) and the middle part of the auxiliary moving knife swing bar (8), three holes form a triangular distribution. 5. The driving and thread trimming mechanism of a sewing machine according to claim 1 or 4, characterized in that: the auxiliary knife swing lever (8) and the thread trimming drive shaft (5) are in clearance fit. 6. The driving and thread trimming mechanism of a sewing machine according to claim 1, characterized in that: the opening slot of the thread trimming drive shaft (5) is connected with the slider (3c) of the thread trimming drive cam crank assembly (3) ), the thread trimmer drive cam crank assembly (3) is fixedly connected to the thread trimmer drive shaft (5) through the slider (3c). 7. The driving and thread trimming mechanism of the sewing machine according to claim 1, characterized in that: the driving shaft (13) is arranged parallel to the transmission shaft (1). 8. The driving and thread trimming mechanism of a sewing machine according to claim 1 or 7, characterized in that: the thread trimming drive shaft (5) is arranged parallel to the drive shaft (13). 9. The driving and thread trimming mechanism of the sewing machine according to claim 1, wherein the driving source is an electromagnet or an air cylinder.