CN108374245B - Operation method of thread clamping device of sewing machine - Google Patents

Abstract

The invention provides a thread clamping device of a sewing machine and an operation method thereof. The thread clamping device comprises a machine head, a needle, a rotary hook, a first thread clamp, a second thread clamp and a thread take-up lever arranged on the machine head ; The needle is provided with a needle eye for the suture to pass through, and the suture passes through the second thread clamp, the thread take-up lever, the first thread clamp, and the needle eye of the machine needle in turn. When the needle pierces the sewing material downwards , the second thread clamp loosens the suture; when the thread is hooked by the hook located below the sewing material, and the thread take-up lever moves upward to take up the thread, the first thread clamp clamps the suture. The thread clamping device and the operation method thereof can precisely adjust the timing of thread clamping and thread loosening, control the amount of compensation for risks, avoid needle breakage or bottom thread during sewing operations, and ensure the beauty of sewn products.

Description

How to operate the thread clamping device of the sewing machine

This application is a divisional application for an invention patent application entitled "Sewing Machine Removing Bird's Nest Device and Using Method", the domestic application date is June 24, 2015, and the national application number is 2015103494116.

technical field

The invention relates to a sewing machine removing bird's nest device.

The invention also relates to a method for using the sewing machine to remove the bird's nest device.

Background technique

When the sewing machine sews fabrics, it is necessary to leave a certain length of thread at the needle eye of the machine needle at the beginning of sewing, so as to ensure that the thread end will not come out of the needle eye when starting the sewing, but a certain length of thread on the needle eye of the machine needle will start. When sewing, it will stay in the initial sewing position of the sewing material, which will affect the beauty of the sewing material.

The current processing methods mainly include the following.

One treatment method is to manually pull the thread end at the beginning of sewing, so that the thread end remains on the sewing material, and manually trim the thread end after the sewing work is finished.

Another treatment method is to use the thread puller to pull up the thread end at the end of the previous sewing, and in the next sewing, rely on the action of the sewing machine to stab the cloth and hook the thread to bring the thread end under the sewing material to ensure the front of the sewing material. beautiful.

At present, there is also a more common way to set an electronic thread clamp in the thread passage channel of the machine head. When the sewing starts, the electronic thread clamp acts to clamp the suture for a certain period of time, so that the dangling thread end is taken when the sewing starts. To the bottom of the sewing material, and by clamping the suture, the thread is supplied by pulling back the thread amount of the needle thread at the beginning of the seam, and finally the length of the thread under the sewing material is shortened.

The latter two ways of handling the thread ends, due to the rapid movement of the sewing machine, will accumulate the thread ends under the sewing material at the start of the seam, forming a bird's nest-like clump, commonly known as the "bird's nest" phenomenon, especially in the automatic reinforcement method at the beginning of the seam, the position of the seam The "Bird's Nest" phenomenon is particularly obvious. Although these two methods solve the problem of thread ends above the upper thread, they transfer the thread ends to the bottom of the sewing material, forming the problem of bird's nest thread.

At present, there is a method in the industry to clamp the thread end by sliding the thread clamping device, and set a blade on the presser foot. When the sewing starts, the thread end is cut off on the edge of the presser foot by the thread setting device and the sewing material, so as to solve the problem of "bird's nest". question. But in this way, because the thread end is clamped, when the first stitch is started, the upper thread is stretched and the thread end of the bottom thread will be brought to the sewing material, resulting in the problem of the bottom thread. One way to solve this problem is to loosen the upper thread in the thread path of the machine head through a set of thread punching device after clamping the thread end, so that there is enough upper thread amount when starting the seam, so as to avoid the problem of the bottom thread. However, the threading method in this method is unstable and often excessive, resulting in insufficient tightening of the starting thread, delay in the cutting time, and excessively long residual thread after cutting. At the same time, the fixed-stroke threading device cannot meet the needs The problem of instability of the starting seam and the closing thread with different distances and different thread quantities. In addition, due to the limited space at the machine head, the sliding thread clamping device needs to be close to the presser foot and the needle stop position of the machine needle, which will affect the passage of the fabric during normal sewing operations and cause the problem of hanging the cloth; the thread end is hooked and pulled In the thread clamping piece and the slide rail, when the hook leaves the thread clamping piece, the thread end is difficult to escape from the thread clamping piece, resulting in accumulation; in order to prevent the blade from being away from the sewing side, the bottom of the presser foot will be damaged and the thread groove, and the blade will cut off the normal sewing thread. , it is necessary to make the blade set a certain distance from the needle eye line of the sewing material, which will cause a long thread residue on the fabric when the thread is cut.

Therefore, in view of the above description, none of the existing devices can well solve the problem that the thread ends tend to accumulate under the sewing material during the sewing process, forming a bird's nest-shaped clump.

SUMMARY OF THE INVENTION

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a sewing machine removing bird's nest device and a method of use, which are used to solve the problem that the thread ends are easily accumulated under the sewing material during the sewing process of the sewing machine in the prior art, forming a bird's nest-shaped clump The problem.

In order to achieve the above purpose and other related purposes, the present invention provides a device for removing bird's nest from a sewing machine. The sewing machine includes a machine head and a needle plate below the machine head. Needle and presser foot plate, the hook is connected with the machine head through the rotating shaft, the needle is provided with a needle eye for the sewing thread to pass through, the presser foot plate is located on the needle plate, and the presser foot plate is provided with a thread passage corresponding to the needle. It extends along the moving direction of the sewing material, and there is a thread cutting knife at the bottom of the wire groove; the rotating shaft drives the hook to rotate around the axis of the rotating shaft between the needle and the thread clamping plate under the drive of the driving mechanism. When the hook is located under the needle , hook up the suture under the needle eye of the machine needle, when the retractor rotates to the position matched with the thread clamping plate, the retracting hook and the thread clamping plate clamp the suture.

Preferably, the clamping plate is fixedly connected to the handpiece through the connecting plate. Further preferably, a pressure plate spring is also fixed on the connection plate, the pressure plate spring is located on the side of the clamping plate facing away from the connection plate, and the pressure plate spring exerts pressure on the clamping plate in the direction of the connection plate. Further preferably, the connecting plate is fixedly connected with the pressure plate spring and the clamping plate through the pressure plate fixing bolts, and there is an adjustment gap between the clamping plate and the connecting plate; there is also a pressure plate adjuster on the connecting plate, and the pressure plate adjuster includes an adjuster. The head and the threaded connection part, the head of the adjuster is located on the side of the pressure plate spring facing away from the wire clamping plate, and the threaded connection part passes through the pressure plate spring, the wire clamping plate in turn, and is connected with the connecting plate threadedly after adjusting the gap.

Preferably, the opening and bottom of the wire-passing groove of the presser foot plate are located on the center line of the presser foot plate, the bottom of the wire-passing groove is divided into an off-line part and a secant line, the off-line part extends along the center line of the presser foot plate, and the secant part The starting end of the presser foot plate is located on the center line of the presser foot plate, the secant line is bypassed from one side of the off-line part, and extends in an arc to the center line of the presser foot plate, and the secant knife is located at the bottom of the secant line.

Preferably, the driving mechanism of the rotating shaft includes a bracket, a crank, a connecting rod and a suction iron core, the bracket is fixed to the machine head, the rotating shaft is located on the bracket and can rotate around the axis, and the rotating shaft is also fixedly connected to one end of the crank, and the end of the crank far from the rotating shaft It is hinged with one end of the connecting rod, the hinge axis of the connecting rod is parallel to the axis of the rotating shaft, and the other end of the connecting rod is connected with the suction iron core, which is controlled by the electromagnet to pull in; when the electromagnet is energized, the suction iron core is closed. Pulling and closing, the connecting rod drives the hook to rotate in the direction of the needle through the crank and the rotating shaft.

Preferably, the machine head is further provided with a first thread gripper, a second thread gripper, and a thread take-up lever, and the suture passes through the second thread gripper, the thread take-up lever, the first thread gripper, and the needle eye of the machine needle in sequence. . Further preferably, the first thread gripper includes an electromagnet base and a splint, the suture passes between the electromagnet base and the splint, and when the electromagnet base is energized, the electromagnet base and the splint are pulled together to clamp the suture. In another further preference, the second wire gripper includes a wire gripper, the wire gripper is provided with a wire gripping groove with variable width along the circumferential direction, one end of the wire gripper is threadedly connected with the wire gripping adjusting bolt, and the thread gripping adjusting bolt is sleeved There is a compression spring, the other end of the wire clamping piece is fixedly connected with the wire release ejector rod, and the end of the wire release ejector rod away from the wire clamping piece corresponds to the wire release electromagnet; the wire release electromagnet is energized, and the end of the wire release ejector rod It is attracted by the wire-releasing electromagnet, and the wire-clamping groove of the wire-clamping piece is widened.

In order to achieve the above-mentioned purpose and other related purposes, the present invention also provides a method for using the above-mentioned sewing machine to remove the bird's nest device, comprising the following steps:

1) After the thread trimming is completed at the end of the last sewing, the drive mechanism is energized, and the rotating shaft drives the hook to rotate under the needle under the drive of the drive mechanism, and hooks the thread end of the suture below the needle eye of the needle;

2) When the drive mechanism is powered off, the rotating shaft drives the retractor to reset, and the thread end hooked by the retractor is clamped between the retractor and the clamping plate;

3) Start sewing, the needle starts to sew, the suture is sewn on the sewing material, and the thread end is left on the sewing material;

4) The sewing material moves to the bottom of the thread slot of the presser foot plate during the sewing process. When the thread end sewn on the sewing material touches the thread cutter, the thread end is cut by the thread cutter, and the thread end is left in the hook and clamp. between the wire boards;

5) When the sewing is over and the thread trimming is completed, the drive system is powered on, and the rotating shaft drives the hook to rotate under the drive of the drive mechanism, and the thread ends originally clamped between the hook and the thread clamping plate fall off.

Preferably, the machine head is further provided with a first thread gripper, a second thread gripper, and a thread take-up lever, and the suture passes through the second thread gripper, the thread take-up lever, the first thread gripper, and the needle eye of the machine needle in sequence. ; Step 3) comprises the following steps:

①When the needle pierces the sewing material downward, the second thread clamp releases the sewing thread;

②When the thread is hooked by the hook located under the sewing material, and the thread take-up lever moves upward to take up the thread, the first thread clamp clamps the thread.

As mentioned above, the sewing machine of the present invention has the following beneficial effects:

The sewing machine removes the bird's nest device and the method of use, adopts the arc swinging hook and thread clamping device to clamp the thread end of the machine needle after the thread is trimmed. The next time the sewing machine is started, the thread release time of the two thread clamps is used to coordinate the thread release time. Start sewing to provide enough stable thread volume, so that the upper thread can be quickly tightened without the bottom thread, the clamped thread is cut near the needle hole of the sewing material, and the residual thread is short, which completely solves the problem of the bird's nest thread. question.

Description of drawings

Fig. 1 is a schematic diagram showing the structure of the device for removing bird's nest in the sewing machine of the present invention.

Fig. 2a is a schematic view of the structure of the sewing machine shown in Fig. 1 when the retractor of the bird's nest removing device is located below the needle.

Fig. 2b is a partially enlarged schematic view of the bird's nest removing device of the sewing machine shown in Fig. 2a.

FIG. 3 is a rear view showing the bird's nest device of the sewing machine shown in FIG. 1 .

FIG. 4 is a partial top view of the bird's nest removing device of the sewing machine shown in FIG. 1 .

Fig. 5a is a diagram showing the relative positional relationship between the sewing thread and the needle, the hook, the thread clamping plate and the presser foot plate during the sewing process of the bird's nest device of the sewing machine shown in Fig. 1 .

Fig. 5b shows a top view of the bird's nest removal device of the sewing machine shown in Fig. 5a.

Fig. 5c is a cross-sectional view taken along the line A-A of the sewing machine shown in Fig. 5b for removing the bird's nest device.

Fig. 5d is a partial enlarged view of the bird's nest removing device of the sewing machine shown in Fig. 5b.

FIG. 6 is a schematic structural diagram of the first embodiment of the driving mechanism of the bird's nest removing device of the sewing machine shown in FIG. 1 .

FIG. 7 is a schematic structural diagram of the second embodiment of the driving mechanism of the bird's nest removing device of the sewing machine shown in FIG. 1 .

Fig. 8a is a schematic structural diagram of the first thread gripper of the bird's nest removing device of the sewing machine shown in Fig. 1 .

Fig. 8b is a schematic view of the first thread gripper of the bird's nest removing device of the sewing machine shown in Fig. 8a in the direction A-A.

Fig. 9a is a schematic view of the thread loosening electromagnet of the second thread gripper of the bird's nest device of the sewing machine shown in Fig. 1 when the power is turned off.

Fig. 9b is a schematic view of the sewing machine shown in Fig. 9a when the thread loosening electromagnet of the second thread gripper of the bird's nest device is energized.

Component label description

1 head

2 needle plate

3 hooks

301 Retractor hook head

4 clamp plate

5 needles

501 Eye of a Needle

6 Presser foot plate

601 Wireway

602 Wireway opening

603 Bottom of wire slot

604 Disconnection

605 Secant

7 reels

8 stitches

801 thread

9 cutting knife

901 Secant knife edge

10 drive mechanism

101 bracket

102 Crank

103 connecting rod

104 Leverage

105 suction core

106 Electromagnet

11 Connection board

111 Connecting plate long slot

12 Compression leaf spring

13 Platen fixing bolts

14 Adjust the gap

15 Platen adjuster

151 Adjuster head

152 Threaded connection

16 First thread clamp

161 Electromagnet Holder

162 splint

17 Second thread clamp

171 Wire clip

172 Wire Slot

173 Thread tension adjustment bolt

174 Compression spring

175 Line release ejector

176 Loose wire electromagnet

177 Adjusting spring

Detailed ways

The embodiments of the present invention are described below by specific embodiments, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

Please refer to Figure 1 to Figure 9b. It should be noted that the structures, proportions, sizes, etc. shown in the drawings in this specification are only used to cooperate with the contents disclosed in the specification, so as to be understood and read by those who are familiar with the technology, and are not used to limit the implementation of the present invention. Restricted conditions, it does not have technical substantive significance, any structural modification, proportional relationship change or size adjustment, without affecting the effect that the present invention can produce and the purpose that can be achieved, should still fall within the present invention. The scope of the disclosed technical content can be covered. At the same time, the terms such as "up", "down", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and clarity, and are not used to limit this specification. The implementable scope of the invention, and the change or adjustment of the relative relationship thereof, shall also be regarded as the implementable scope of the present invention without substantially changing the technical content.

As shown in FIGS. 1 to 4 , the present invention provides a device for removing bird’s nest in a sewing machine. The sewing machine includes a machine head 1 and a needle plate 2 located below the machine head 1 . The thread plate 4, the needle 5 and the presser foot plate 6, the hook 3 is connected to the machine head 1 through the rotating shaft 7, the needle 5 is provided with a needle eye 501 for the sewing thread 8 to pass through, the presser foot plate 6 is located on the needle plate 2, and the presser foot plate 6. There is a wire-passing groove 601 corresponding to the needle 5. The wire-passing groove 601 extends along the direction of the movement of the sewing material. The bottom 603 of the wire-passing groove 601 is provided with a cutting knife 9; the rotating shaft 7 is driven by the driving mechanism 10. Drive the retractor 3 to rotate around the axis of the rotating shaft 7 between the needle 5 and the thread clamping plate 4. When the retractor 3 is located under the needle 5, hook up the suture 8 under the needle eye 501 of the needle 5, and the retractor 3 rotates to In the position matched with the thread clamping plate 4, the hook 3 and the thread clamping plate 4 clamp the suture 8.

The suture 8 passes through the needle eye 501 of the machine needle 5 , and the suture 8 located under the needle eye 501 of the machine needle 5 is the thread head 801 . Before sewing starts, the drive mechanism 10 is powered on, and the rotating shaft 7 drives the retractor 3 to rotate under the needle 5 under the drive of the drive mechanism 10, and the hook head 301 of the retractor 3 hooks up the thread end 801 below the needle eye 501 of the needle 5; The drive mechanism 10 is powered off, the rotating shaft 7 drives the retracting hook 3 to reset, and the thread end 801 hooked by the retracting hook 3 is clamped between the retracting hook 3 and the wire clamping plate 4 . Start sewing, the needle 5 starts to sew, the sewing thread 8 is sewn on the sewing material, and the thread end 801 is left on the sewing material; When the thread end 801 sewn on the sewing material touches the thread cutter 9, the thread end 801 is cut by the thread cutter 9, and the thread end 801 is left between the hook 3 and the thread clamping plate 4; when the sewing ends, the cutting is completed. After threading, the drive system 10 is energized, the rotating shaft 7 drives the retractor 3 to rotate under the drive of the drive mechanism 10, the thread end 801 originally clamped between the retractor 3 and the thread clamping plate 4 falls off, and the retractor 3 is located in the needle eye 501 of the needle 5. The new thread end 801 below is hooked up, waiting for the start of the next sewing.

As shown in FIG. 2 b , the clamping plate 4 is fixedly connected to the handpiece 1 through the connecting plate 11 .

A pressure plate spring 12 is also fixed on the connecting plate 11 . The pressure plate spring 12 is located on the side of the clamping plate 4 facing away from the connecting plate 11 . By using the pressure plate spring 12 to exert pressure on the clamping plate 4, there is a certain holding force between the clamping plate 4 and the hook 3, and the retaining force can ensure that the thread end 801 is clamped by the clamping plate 4 and the hook 3 without fall.

A specific structure in which the connecting plate 11 is connected with the pressure plate spring 12 and the clamping plate 4 is shown in FIG. 2 . The connecting plate 11 is fixedly connected with the pressure plate spring 12 and the clamping plate 4 through the pressure plate fixing bolts 13, and an adjustment gap 14 is provided between the clamping plate 4 and the connecting plate 11; The regulator 15 includes a regulator head 151 and a threaded connection part 152. The regulator head 151 is located on the side of the pressure plate spring 12 facing away from the clamping plate 4. The threaded connection part 152 passes through the pressure plate spring 12, the clamping plate 4, and the adjustment gap in sequence. After 14, it is screwed with the connecting plate 11. By rotating the adjuster head 151 to adjust the size of the adjustment gap 14, the pressure of the pressure plate spring 12 on the wire clamping plate 4 can be adjusted, thereby adjusting the holding force between the wire clamping plate 4 and the hook 3.

As shown in FIGS. 5 a to 5 d , the opening 602 and the bottom 603 of the wire passage groove 601 of the presser foot plate 6 are located on the center line of the presser foot plate 6 , and the bottom 603 of the wire passage groove 601 is divided into an off-line part 604 and a secant part 605 , the off-line portion 604 extends along the centerline of the presser foot plate 6, the starting end of the secant portion 605 is located on the centerline of the presser foot plate 6, and the secant-line portion 605 bypasses one side of the off-line portion 604 and extends in an arc until On the center line of the presser foot plate 6, the cutting knife 9 is located at the bottom of the cutting part 605, and the cutting edge 901 of the cutting knife 9 faces the direction of the opening 602 of the wire groove 601.

Since the side close to the needle plate 2 is provided with the off-thread part 604, and the cutting part 605 bypasses the off-thread part 604, the stitches sewed on the sewing material during sewing are usually placed on the off-thread part 604, and will not be cut. In the thread part 605, the sewing thread during sewing is prevented from being rubbed off by the thread cutting knife 9 arranged in the cutting thread part 605; and the bottom of the cutting thread part 605 is located on the center line of the presser foot plate 6, so that the thread cutting knife 9 and The distance between the stitches of the sewing material is the shortest, so that the stitches where the thread end 801 is cut are close to the stitches of the sewing material, so as to ensure that the remaining thread ends on the sewing material are short.

The driving mechanism 10 of the rotating shaft 7 has various specific implementations. The driving mechanism 10 includes a bracket 101 fixed with the machine head 1, and the rotating shaft 7 is located on the bracket 101 and can rotate around the axis. When the driving mechanism 10 is energized, the rotating shaft 7 drives the retractor 3 to rotate in the direction of the needle 5, and the needle 5 is rotated. The thread end 801 below the needle eye 501 is hooked up, and when the driving mechanism 10 is powered off, the rotating shaft 7 is reset, and the thread end 801 hooked by the retractor 3 is clamped between the retractor 3 and the thread clamping plate 4. The specific implementation of the drive mechanism 10 is shown in the figure 6 and Figure 7.

As shown in FIG. 6 to FIG. 7 , the driving mechanism 10 of the rotating shaft 7 includes a bracket 101 , a crank 102 , a connecting rod 103 and a suction iron core 105 , the bracket 101 is fixed to the handpiece 1 , and the rotating shaft 7 is located on the bracket 101 and can rotate around the axis , the rotating shaft 7 is also fixedly connected with one end of the crank 102, the end of the crank 102 away from the rotating shaft 7 is hinged with one end of the connecting rod 103, the hinge shaft of the connecting rod 103 is parallel to the axis of the rotating shaft 7, and the other end of the connecting rod 103 is connected to the suction iron The core 105 is connected, and the pull-in iron core 105 is controlled by the electromagnet 106 to pull in; when the electromagnet 106 is energized, the pull-in iron core 105 pulls in, and the connecting rod 103 drives the hook 3 to rotate in the direction of the needle 5 through the crank 102 and the rotating shaft 7 . The connecting rod 103 and the suction iron core 105 are connected in two ways. The first connection method is shown in FIG. 6 . 101 Fixed connection; the second connection mode is shown in FIG.

The electromagnet 106 in the above-mentioned driving mechanism 10 can be replaced by an air cylinder or a motor.

As shown in FIG. 6 to FIG. 7 , the connecting plate 11 can also be fixed on the bracket 101 , a long slot 111 is provided at the fixing place between the connecting plate 11 and the bracket 101 , and the connecting plate 11 is fixed by a bolt passing through the long slot 111 and fixing the bracket 101 11 and bracket 101. Since the bolt has a certain space for movement in the long groove 111 , the relative position of the connecting plate 11 and the bracket 101 can also be adjusted, thereby adjusting the relative position of the clamping plate 4 fixed on the connecting plate 11 .

As shown in Figures 1 and 8a to 9b, the machine head 1 is also provided with a first thread gripper 16, a second thread gripper 17, and a thread take-up lever, and the suture 8 passes through the second thread gripper 17, The thread take-up lever, the first thread clamp 16, and the needle eye 501 of the needle 5.

As shown in FIGS. 8 a to 8 b , the first thread gripper 16 includes an electromagnet seat 161 and a clamping plate 162 , and the suture 8 passes between the electromagnet seat 161 and the clamping plate 162 . When the electromagnet base 161 is energized, the electromagnet base 161 and the splint 162 are pulled together to clamp the suture 8; when the electromagnet base 161 is powered off, the electromagnet base 161 and the splint 162 release the suture 8.

As shown in FIGS. 9 a to 9 b , the second thread gripper 17 includes a thread tensioning piece 171 . The thread tensioning piece 171 is provided with a thread clamping groove 172 of variable width along the circumferential direction. Connection, the tensioning adjustment bolt 173 is covered with a compression spring 174, and the other end of the tensioning piece 171 is fixedly connected with the release ejector rod 175, and the end of the release ejector rod 175 away from the tensioning piece 171 is in contact with the release electromagnet 176. Correspondingly: when the wire-releasing electromagnet 176 is energized, the end of the wire-releasing ejector rod 175 is attracted to the wire-releasing electromagnet 176, and the wire clamping slot 172 of the wire clamping piece 171 is widened. An adjustment spring 177 is also sleeved on the thread release ejector rod 175 .

As shown in FIG. 9a , the thread release electromagnet 176 is powered off, and the thread clamping slot 172 clamps the suture 8 ; as shown in FIG. 9b , the thread release electromagnet 176 is energized, and the thread is released at this time. The end of the ejector rod 175 engages with the thread release electromagnet 176 , the thread clamping groove 172 is widened, and the suture 8 can slide in the thread clamping groove 172 without resistance.

The power-on and power-off time points of the above-mentioned loosening electromagnet 176 and the electromagnet base 161 are intelligently switched by the electronic control mode according to different operations.

At the beginning of sewing, the thread end 801 continues to be clamped. As the needle 5 pierces the cloth downward, the thread loosening electromagnet 176 is energized, and the thread clamping slot 172 releases the thread, ensuring that the machine can sew downward without any resistance to the thread supply; Rotary hook hooks the thread, when the thread take-up lever moves upward to take up the thread to near the highest point, because the thread end 801 is clamped above when the sewing starts, and a thread loop is sewn to consume a part of the thread, if the thread continues to take up at this time, it will cause In order to avoid the phenomenon that the loop formed before is pulled out of the sewing material and the end of the bottom thread is taken out, the first thread clamp 16 is powered on at this time to clamp the seam between the thread take-up lever and the needle 5 thread 8, so that when the thread take-up lever continues to rise, it will not take up the thread from one side of the needle 5, but can draw the thread from one side of the second thread gripper 17, so as to ensure that the thread loop and the bottom thread are not taken out. The sewing material can also ensure that the sewing thread 8 is not torn when the thread is taken up. Through the time matching of the above-mentioned loosening and clamping, it is ensured that there is no bottom thread at the start of the seam, the stitches are beautified, and the performance of the bird's nest removing device is stabilized.

The above-mentioned method of using the sewing machine to remove the bird's nest device mainly includes the following steps:

1) After the thread trimming is completed at the end of the previous sewing, the driving mechanism 10 is energized, and the rotating shaft 7 drives the retractor 3 to rotate to the bottom of the needle 5 under the driving of the driving mechanism 10, and the thread end of the suture 8 below the needle eye 501 of the needle 5 is removed. 801 hook up;

2) The drive mechanism 10 is powered off, the rotating shaft 7 drives the pull hook 3 to reset, and the thread end 801 hooked by the pull hook 3 is clamped between the pull hook 3 and the wire clamping plate 4;

3) Start sewing, the needle 5 starts to sew, the thread 8 is sewn on the material, and the thread end 801 is left on the material; wherein, when the needle 5 pierces the material downward, the second thread clamp 17 is released The suture 8; when the suture 8 is hooked by the hook located under the sewing material, and the thread take-up lever moves upward to take up the thread, the first thread clamp 16 clamps the suture 8;

4) The sewing material moves toward the bottom 603 of the thread-passing groove 601 of the presser foot plate 6 during the sewing process. When the thread end 801 sewn on the sewing material touches the thread cutting knife 9, the thread end 801 is cut by the thread cutting knife 9. The thread end 801 is left between the draw hook 3 and the thread clamping plate 4;

5) When the sewing is finished and the thread trimming is completed, the drive system 10 is powered on, and the rotating shaft 7 drives the hook 3 to rotate under the drive of the drive mechanism 10, and the thread end 801 originally clamped between the hook 3 and the thread clamping plate 4 falls off.

The sewing machine of the present invention removes the bird's nest device through the arc swinging hook 3 and the thread clipping plate 4 to clamp the thread, and cooperates with the optimally designed presser plate 6 with a secant knife 9 to secant the thread when starting the sewing; the arc swinging hook 3 and the thread clamp The setting of the plate 4 completely solves the problem of the sewing operation space, and the one-way thread clamping structure is adopted, so that the thread end 801 can be quickly released from the thread clamping sheet 4, and the accumulation of thread ends is avoided; In this way, the off-line part 604 of the presser foot plate 6 is protected, and at the same time, the secant knife 9 is close to the needle hole line of the sewing material, so that the knife edge is closer to the needle hole line when the secant knife 9 cuts the line, and the residual thread on the sewing material is shorter. At the same time, the hooking range is effectively controlled; through the coordination of the time between the first thread clamp 16 and the second thread clamp 17 on the thread passage channel of the machine head 1 to clamp the thread and release the thread, it can solve the problem caused by the thread end being clamped. The problem of the bottom thread of the seam belt saves the threading device, and stabilizes the amount of thread for starting the seam, avoiding the unstable threading amount and the inability of the threading device with a fixed stroke to meet the need for different thread quantities due to different stitch lengths. The problem of unstable sewing thread.

To sum up, the sewing machine of the present invention removes the bird's nest device and the method of use, adopts the arc swinging hook thread clamping device, clamps the thread end of the machine needle after the thread is trimmed, and loosens the thread through the clamping of the two thread clamps when the sewing starts next time. The coordination of the thread time provides a stable enough thread volume for the start of sewing, so that the upper thread can be quickly tightened without the bottom thread, and the clamped thread ends are cut off at the position close to the needle hole of the sewing material, and the remaining thread ends are short. Completely solve the problem of the bird's nest thread. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

The above-mentioned embodiments merely illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed in the present invention should still be covered by the claims of the present invention.

Claims (4)

1. The operating method of the thread clamping device of the sewing machine is characterized in that the thread clamping device comprises a machine head (1), a machine needle (5), a rotating shuttle, a first thread clamping device (16) arranged on the machine head (1), a second thread clamping device (17) and a thread take-up lever; a needle eye (501) for the suture (8) to pass through is arranged on the machine needle (5), and the suture (8) sequentially passes through the second thread clamp (17), the take-up lever, the first thread clamp (16) and the needle eye (501) of the machine needle (5); the method comprises the following steps:

firstly, when the needle (5) pierces the sewing material downwards, the second thread grip (17) loosens the sewing thread (8);

secondly, when the thread (8) is hooked by the rotating shuttle positioned below the sewing material and the take-up lever moves upwards to take up the thread, the first thread clamping device (16) clamps the thread (8).

2. The method of operating a thread tension device of a sewing machine according to claim 1,

in the second step, when the suture (8) passes through the rotating shuttle hook wire and the take-up lever moves upwards to take up the suture to be close to the highest point, the first thread clamping device (16) clamps the suture (8) between the take-up lever and the machine needle (5).

3. The method of claim 1, wherein the first thread clamping device (16) comprises an electromagnet base (161) and a clamping plate (162), the thread (8) passes through the space between the electromagnet base (161) and the clamping plate (162), when the electromagnet base (161) is energized, the electromagnet base (161) and the clamping plate (162) are attracted to clamp the thread (8), and when the electromagnet base (161) is de-energized, the electromagnet base (161) and the clamping plate (162) loosen the thread (8).

4. The operating method of the thread clamping device of the sewing machine is characterized in that the second thread clamping device (17) comprises a thread clamping sheet (171), the thread clamping sheet (171) is provided with a thread clamping groove (172) with variable width along the circumferential direction, one end of the thread clamping sheet (171) is in threaded connection with a thread clamping adjusting bolt (173), a compression spring (174) is sleeved on the thread clamping adjusting bolt (173), the other end of the thread clamping sheet (171) is fixedly connected with a thread releasing ejector rod (175), and the end part of the thread releasing ejector rod (175), which is far away from the thread clamping sheet (171), corresponds to a thread releasing electromagnet (176); the thread releasing electromagnet (176) is electrified, the end part of the thread releasing ejector rod (175) is attracted with the thread releasing electromagnet (176), and a thread clamping groove (172) of the thread clamping piece (171) is widened.

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