CN1036214C - Thread cutting device for multi-needle sewing machine - Google Patents

Abstract

A thread cutting device for a multi-needle sewing machine in which the hook needles make horizontal and linear reciprocating motions. The device is installed on a plate below the needle plate of a multi-needle sewing machine. The upper cutter and the lower cutter are to be When in position, retreat a considerable distance to avoid collision with the moving hook needle, and only push the upper cutter and the lower cutter forward to a certain point when cutting the thread, and then the lower cutter extends forward to catch the needle thread and hook thread And the hook thread is introduced into the clamping device so that the thread is clamped, and the needle thread and the hook thread are cut off successively by the upper cutter, so the thread will not fall off, the components of the cutting device will not collide with the hook needle, and the cut hook thread end is shorter , simple in structure and easy to manufacture.

Description

Thread cutting device for multi-needle sewing machine

The invention relates to a thread cutting device for a multi-needle sewing machine, in particular to a thread cutting device that can reliably prevent the components of the thread cutting device from colliding with and interfering with the hook needles that move horizontally and linearly in the sewing machine, and ensure that the thread cutting device does not interfere with each other during each sewing. Thread cutting device capable of sewing, cutting, clamping and sewing again.

Multi-needle sewing machines have been widely used at present, whether they are used in homes or factories, and most of the sewing of multi-needle sewing machines is carried by multiple needles on the needle board of the sewing machine, and there is a crochet thread under the needle board. Its sewing principle and action are not the issues discussed in this case and are omitted here. What the present invention will discuss is the problem when the sewing is finished and the thread needs to be cut off once and then engaged to continue the sewing. The known thread cutting device of multi-needle sewing machine, such as in the patent application No. 75288507 in Taiwan, discloses a kind of thread cutting device of multi-needle sewing machine, which uses a linkage device to affect the cutting knife of the thread cutting device to Carry out the angle movement to hook, cut, and clamp the thread, and sandwich the thread between the cutting plate and the catching member after each sewing to facilitate the next sewing action, although the patent application The discussed use of the overall mechanism to make an angular movement of the line to facilitate hooking, cutting, and clamping, but basically there are two disadvantages as follows:

(1) The movement track of the catch member is a prying type arc track, which is easy to collide with the hook needle and be damaged.

(2) Since the thread needs to be clamped, the catching member and the needle plate should not be too far apart. They need to be quite close to ensure thread clamping. However, if they are too close, they will easily interfere with the hook needle. If it is too far, the hook thread end that is cut off is too long.

Therefore, the object of the present invention is to provide a thread cutting device for a multi-needle sewing machine, the hook needles of the thread cutting device will not be damaged due to collision with the catch member, etc., and the cut hook thread ends are relatively short, and The cut hook thread end can be clamped instantly to ensure that it will not come off the thread, which is beneficial to the next sewing.

The present invention provides a thread cutting device for a multi-needle sewing machine, the hook of which moves horizontally and rectilinearly. The device is installed under the needle plate of a multi-needle sewing machine, including:

A plate body is provided with a configuration groove and a plurality of protruding shafts, and a return spring is provided on one of the protruding shafts, and the return spring is fixed to the plate through a spring seat and one of the plurality of protruding shafts On the body, the spring seat is also provided with a stage piece and a spring; the other of the plurality of protruding shafts is provided with a latch and is controlled by another spring;

The thread cutting device is formed by the juxtaposition of the lower cutter slide and the upper cutter slide, wherein one end of the lower cutter slide is provided with a lower cutter, the lower cutter has front and rear hooks, and the front hook The edge of the knife tip is provided with a downwardly curved guide piece to form a sloped side extending from the knife tip; and the upper side of one end of the upper knife slide is also provided with an upper knife, and is formed by the plate body The spring seat, the stage piece, and the spring are supported and restrained by the bamboo shoots, and the lower surface is provided with a clip to support the lower cutter; the device is arranged side by side according to the other ends of the two slides. and the lower cutter is located between the upper cutter and the clip; each of the two slides is provided with a flange that can pull each other, and one end of the lower cutter slide is provided with a The protruding handle, the upper cutter slide is provided with a push rod protruding from the roughly central part; the push rod is supported by the return spring set on one of the above-mentioned body protruding shafts;

A linkage device, a long plate, sleeved on one of the protruding shafts of the plate body and swinging with the protruding shaft as a fulcrum, one end is provided with a long slot, and the protruding handle of the lower cutter slide It is inserted into the chute; the other end is also provided with a long slot to receive the transmission power of the cylinder; the interlocking device is provided with a protruding shaft near the central part, so that when the interlocking device swings, it can pass through the setting The protruding shaft at the central part of the linkage device pushes the stage member of the plate body, and then rotates the angular orientation of the spring seat, so as to increase the elastic force of the return spring;

A clamping device, including a mounting plate body, one end of the mounting plate body is provided with a straight pin, and a protruding shaft and a screw are arranged on the surface of the mounting plate body; a shrapnel is provided on the protruding shaft, and the shrapnel has a flange And there is a cover at the end of the shrapnel, which is located directly above the direct pin; the screw is used to fix a spring, and the spring presses the shrapnel so that the flange of the shrapnel is in contact with the direct pin; The mounting plate body is installed in the mounting groove of a mounting seat.

The thread cutting device of the multi-needle sewing machine provided by the present invention is provided with a thread clamping device at an appropriate position on the side of the above thread cutting device, so the cut hook thread ends can be instantly clamped by the thread clamping device to facilitate The next sewing is carried out.

Another feature of the present invention is that the above-mentioned thread cutting device is far away from and does not hinder the sewing stroke of the sewing needle and hook needle when the thread cutting action is not started, and when the thread cutting action is started, the sewing needle rises to the top dead center , the hook needle moves to the left dead point, and all the threads are loosened. At this time, the above-mentioned thread cutting device starts to act, and sends the upper and lower cutters used for thread cutting to a certain point for positioning, and then begins to cut the thread from this point. The lower cutter stretches out to catch the needle thread and hook thread. At this time, the lower cutter first pushes away the shrapnel on the thread clamping device, and then guides the hook thread into the clamping thread against the downward curved guide set on the edge of the lower cutter. Between the direct pin on the device and the pushed shrapnel, the lower cutter catches the needle thread and the hook thread continues to retreat to the fixed-point standby position of the upper cutter, and then cooperates with the upper cutter to cut off the needle thread first, and then cuts off the hook thread, and is cut off The crochet thread is clamped by the direct pin on the thread clamping device and the elastic piece that returns to the original position, so as to prepare for the next sewing.

The purpose and characteristics of the present invention are described in detail below with reference to the following drawings and their preferred embodiments:

Fig. 1 is a three-dimensional exploded schematic diagram of partial components of the thread cutting device of the multi-needle sewing machine of the present invention.

Fig. 2 is a combined perspective schematic diagram of the above-mentioned Fig. 1 of the present invention.

Fig. 3 is a three-dimensional exploded schematic diagram of the thread clamping device of the thread cutting device of the multi-needle sewing machine of the present invention.

Fig. 4 is a side view of the lower cutter of the thread cutting device of the multi-needle sewing machine of the present invention.

Fig. 5 A, B, C, D, E are the schematic diagrams of the continuous actions of the thread cutting device and the interlocking device of the thread cutting device of the multi-needle sewing machine of the present invention for standby, thread hooking, thread cutting, clamping, and return.

Fig. 6 Fig. A, B, C, D is the thread cutting device part and the thread clamping device part of the thread cutting device of the multi-needle sewing machine of the present invention, and the continuous action schematic diagram of thread hooking, thread cutting and clamping.

First of all, please refer to Fig. 1, Fig. 2 and Fig. 3, which is a preferred embodiment of the present invention, which is installed under the needle plate of a sewing machine with multiple needles; it includes a plate body 10 , a thread cutting device 20, a linkage device 30, and a thread clamping device 80, wherein:

The plate body 10 is provided with a disposing groove 11 and two protruding shafts 13 and 14 , and a return spring 140 is provided on the protruding shaft 14 . The protruding shaft 14 is fixed on the plate body 10 in cooperation with the spring seat 1400 , and the spring seat 1400 is provided with a stage plate 1401 and a spring 1402 . Also, on the protruding shaft 17 is provided with a latch 170 which can be controlled by a spring 171 .

The thread cutting device 20, as shown in Figure 1, comprises a lower cutter slide 21 and an upper cutter slide 22 juxtaposed, wherein an end A of the lower cutter slide 21 is provided with a lower cutter 210, and the lower cutter 210 is as shown in FIG. As shown in Figure 4, it has a front hook portion 2100 and a rear hook portion 2101, and a downwardly curved guide piece 2102 is provided on the edge of the knife tip of the front hook portion 2100. There is a sloped side that expands backward; the upper cutter 220 is certainly provided on the end B of the upper cutter slide 22, but the lower surface is provided with a clip 221 for supporting the lower cutter 210. In this device, the other ends C and D of the two sliding pieces are placed side by side in the above-mentioned board configuration groove 11, and the lower cutting knife 210 is located between the upper cutting knife 220 and the clamping piece 221. A protruding handle 211 is provided at the other end C of the lower cutter slide, and a push rod 223 protrudes from the upper cutter slide 22 approximately in the center. The above-mentioned return spring 140 is pressed on the ejector rod 223 for returning to the original position after the upper cutter device is shifted, and a positioning guide 225 is provided to make the ejector rod 223 a reference point for positioning.

The interlocking device 30 is a long plate, which is sheathed in a protruding shaft 13 of the above-mentioned plate body, and swings with the protruding shaft as a fulcrum. Its one end F is provided with a long groove 31, and above-mentioned lower cutting knife slider lug 211 is inserted in this chute; And its other end E is also provided with a long groove 32, so that the transmission mechanism (not shown) of the sewing machine Transmission, this interlocking device is protrudingly provided with a protruding shaft 33 by central part.

This clamping device 80, as shown in Fig. 3, is installed in the mounting groove 91 of the mounting base 90, and is installed on the sewing machine body by means of the mounting base 90. It includes a mounting plate body 800, one end of the mounting plate body 800 is provided with a straight pin 803, and a protruding shaft 8041 is used to fix the elastic piece 802 so that it can swing, and a screw 8042 is used to fix the spring 801, and screws 8043 and 8044 are used to fix the mounting plate The body 800 is fixed in the installation groove 91 of the installation base 90 . The shrapnel 802 is provided with a flange 8022, under normal conditions, by means of the thrust of the spring 801, the flange 8022 is attached to the straight pin 803; Located directly above the direct sales 803.

Please refer to the 5th Fig. A, B, C, D, E and the 6th Fig. A, B, C, D shown in the following description, for the thread cutting device of the multi-needle sewing machine of the present invention carries out the continuous action of the thread cutting operation.

As shown in Fig. 5A, it is the standby position of the tangent. At this time, the cylinder (not shown) pushes the linkage device 30 to drive the lower cutter slide 21 to pull back, and the elastic force of the spring 140 and the spring 1402 pushes the upper cutter slide 22 forward, impelling the flange 214 and the flange The two points of 224 are close together and are in a standby position.

As shown in Figure 5B, the cylinder pulls the interlocking device 30 by command, so that the lower cutter slide 21 is pushed forward, and the upper cutter slide 22 is also pushed forward simultaneously by the elastic force of the springs 140 and 1402. The upper cutter slide 22 can maintain sufficient elastic force. At this time, the protruding shaft 33 on the interlocking device 30 pushes the stage piece 1401, and then rotates the angular orientation of the spring seat 1400 to enhance the elastic force of the spring. The spring 171 is pushed and rotated to form a clamping effect, which is used to block the positioning, thereby maintaining a certain sufficient elastic force. At this time, the upper cutter slide 22 moves to the top of the positioning guide 225 and stops, while the lower cutter slides. The sheet 21 is also driven by the interlocking device 30 to make the flanges 224 and 214 close together and shift to the fixed point.

As shown in Figure 5C, in the fixed-point positioning state of the upper cutter slide 22, the interlocking device 30 pushes the lower cutter 210 to the left dead point, and uses the rear hook 2101 and the front hook 2100 of the lower cutter 210 respectively. , to catch the needle thread 60 and the hook thread 61, and then the interlocking device 30 operates in reverse, and the lower cutter 210 is pulled back to do the cutting action. Please refer to Figures 6A, 6B, and 6C. When the front hook portion 2100 and the rear hook portion 2101 of the undercut 210 are used to protrude forward to catch the crochet thread 61 and the needle thread 60, the lower cutter 210 resists and pushes away. The elastic piece 802 on the thread clamping device 80 leans against the downwardly curved guide piece 2102 of the lower cutter 210 at the same time, and guides the hook thread 61 downward along the sloped side of the downwardly curved guide piece 2102 into the thread clamping device 80 between the upper straight pin 803 and the shrapnel 802 pushed away by the lower cutter 210 . In addition, the cover 8021 at the end of the elastic piece 802 can also guide the hook thread 61 to enter between the above-mentioned straight pin 803 and the elastic piece 802, and prevent the hook thread 61 from moving out of the gap. (for the clarity of the figure, the action of the needle thread 60 part is omitted in the 6th figure).

As shown in Figure 5D, the lower cutter 210 and the upper cutter 220 positioned at the fixed point constitute a cutting mechanism, which first cuts off the needle thread 60 positioned at the rear hook portion 2101, and then cuts off the hook needle thread 61 positioned at the front hook portion 2100. . At this time, please refer to Figure 6D again. During the process of the lower cutter 210 returning from the left fixed point and cooperating with the upper cutter 220 positioned at the fixed point to cut off the needle thread 60 and hook thread 61, the lower cutter 210 leaves the thread clamping device 80 of the elastic piece 802, the elastic piece 802 is pressed by the spring 801 on the clamping device 80, so that the convex line 8022 on the elastic piece 802 returns to the state of being in contact with the straight pin 803, and thus clamps the The cut crochet thread 61 between the flange 8022 and the straight pin 803 .

Afterwards, as shown in Figure 5E, the interlocking device 30 swings back to its original position, and at the same time drives the upper cutter slide 22 and the lower cutter slide 21 to return to the original standby position, and the cut hook thread 61 has been clamped in the clip. Between the direct pin 803 of the wire device 80 and the elastic piece 802 . In this way, the thread end can be knotted smoothly in the next sewing, and the thread will never come off, and the sewing can be done again and again.

The features of the present invention are as follows: (1) Since the present invention adopts the upper and lower cutters to do the maximum displacement to avoid the collision that may occur when the needle moves horizontally, when cutting the thread, the upper cutter 220 and the lower cutter 210 are moved together Send out to a fixed point location, then just stretch out the lower cutter 210 here to catch the needle thread 60 and hook thread 61, then pull back to this fixed point location and do the cutting action with the upper cutter 220 on standby here. Therefore, the cut hook thread ends are the shortest. (2) After the thread cutting action is completed, the cut hook thread 61 is clamped by the direct pin 803 on the thread clamping device 80 and the flange 8022 on the shrapnel 802, so that the thread end can be smoothly tied when the next sewing is done. Not to go offline. (3) The thread clamping device 80 of the present invention has a simple structure, is easy to manufacture, and can play a good role, meeting the industrial utilization value.

The illustrations and descriptions disclosed above are only preferred embodiments of the present invention, and those who are familiar with the art, the modifications or equivalent changes made according to the spirit of this case should still be included in the patent scope of this application .

Claims (1)

1. A thread cutting device for a multi-needle sewing machine, in which the hook needles do horizontal and linear reciprocating motions. The device is installed under the needle plate of a multi-needle sewing machine, including: A plate body is provided with a configuration groove and a plurality of protruding shafts, and a return spring is provided on one of the protruding shafts, and the return spring is fixed to the plate through a spring seat and one of the plurality of protruding shafts On the body, the spring seat is also provided with a stage piece and a spring; the other of the plurality of protruding shafts is provided with a latch and is controlled by another spring; The thread cutting device is formed by the juxtaposition of the lower cutter slide and the upper cutter slide, wherein one end of the lower cutter slide is provided with a lower cutter, the lower cutter has front and rear hooks, and the front hook The edge of the knife tip is provided with a downwardly curved guide piece to form a sloped side extending from the knife tip; and the upper side of one end of the upper knife slide is also provided with an upper knife, and is formed by the plate body The spring seat, the stage piece, and the spring are supported and restrained by the bamboo shoots, and the lower surface is provided with a clip to support the lower cutter; the device is arranged side by side according to the other ends of the two slides. and the lower cutter is located between the upper cutter and the clip; each of the two slides is provided with a flange that can pull each other, and one end of the lower cutter slide is provided with a The protruding handle, the upper cutter slide is provided with a push rod protruding from the roughly central part; the push rod is supported by the return spring set on one of the above-mentioned body protruding shafts; A linkage device, a long plate, sleeved on one of the protruding shafts of the plate body and swinging with the protruding shaft as a fulcrum, one end is provided with a long slot, and the protruding handle of the lower cutter slide It is inserted into the chute; the other end is also provided with a long slot to receive the transmission power of the cylinder; the interlocking device is provided with a protruding shaft near the central part, so that when the interlocking device swings, it can pass through the setting The protruding shaft at the central part of the linkage device pushes the stage member of the plate body, and then rotates the angular orientation of the spring seat, so as to increase the elastic force of the return spring; A clamping device, including a mounting plate body, one end of the mounting plate body is provided with a straight pin, and a protruding shaft and a screw are arranged on the surface of the mounting plate body; a shrapnel is provided on the protruding shaft, and the shrapnel has a flange And there is a cover at the end of the shrapnel, which is located directly above the direct pin; the screw is used to fix a spring, and the spring presses the shrapnel so that the flange of the shrapnel is in contact with the direct pin; The mounting plate body is installed in the mounting groove of a mounting base.

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