JPH01299590A - Over-lock machine capable of back tuck stitch - Google Patents

Abstract

PURPOSE:To eliminate the need for providing a member projecting above a machining-cloth supporting face by moving the cut end of a cut void ring to the cloth feed-in side of a needle falling point and sucking same downward from the suction port which opens on the machining-cloth supporting face. CONSTITUTION:On the cloth feed-out side of a needle falling point, a supporting body 11 having an air passage 10 which extends nearly along a cloth feeding direction is installed on a bed portion 3, forming a suction device with the air passage 10, a pipe body 13, and a first injection pipe 14 while also forming a moving means with the air passage 10, pipe body 13 and a second injection pipe 15. On the cloth feed-in side of the needle falling point, a suction port 20 is formed on a throat plate 6 and a block body 21 having a suction passage 21a is provided below the throat plate 6. the top-end opening 21b of the suction passage 21a is provided opposite to the suction port 20 while connecting a suction pipe 22 to the bottom end thereof and, by means of a suction air stream generated in the suction passage 21a by an injecting pipe 22a, the cut end of a void ring R is sucked into the suction passage 21a through the suction port 20 and opening 21b.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a suction device that suctions the empty ring of yarn connected to the workpiece cloth at the end of sewing toward the cloth feeding side of the needle drop point, and a suction device that uses the suction device. The present invention relates to an overlock sewing machine equipped with a cutting device that cuts an empty ring of suctioned thread.

[Conventional technology]

Conventionally, for example, Japanese Patent Application Laid-Open No. 53-128443 (Showa 5
In the sewing machine described in the publication (published on November 9, 2013), at the end of sewing, the empty ring of thread connected to the workpiece fabric is cut on the cloth feeding side from the needle drop point, and then the empty ring is cut by air blown from a nozzle. The end is blown back to the cloth feed side beyond the needle drop point, and the cut end of the empty ring is sucked by a suction device having an opening above the work cloth support surface on the cloth feed side from the needle drop point, and then the work cloth support A blade protrudingly disposed so as to be movable up and down on the surface presses and grasps the cut end of the hollow ring onto the work cloth support surface, and the cut end of the hollow ring is sewn into the work cloth to be sewn next. It has become.

[Problem to be solved by the invention]

However, in the above-mentioned sewing machine, the blade and suction device for grasping the cut end of the empty ring on the fabric feeding side rather than the needle drop point are arranged protruding from the workpiece fabric support surface.
When setting the work cloth on the work cloth support surface or transferring the work cloth, there is a problem in that it gets in the way and makes it impossible to handle the work cloth smoothly.

This invention was made in order to solve the above problem, and its purpose is to protrude above the work cloth support surface in order to hold the cut end of the hollow ring closer to the cloth feeding side than the needle drop point. To provide an overlock sewing machine capable of back tank sewing, which does not require the provision of a member to handle the work cloth, and allows easy handling of work cloth.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a moving means for moving the cut end of the empty ring cut by the cutting device to the fabric feed side from the needle drop point, and a moving means for moving the cut end of the empty ring cut by the cutting device to the fabric feed side from the needle drop point. A suction port opening on the work cloth support surface and a suction device for sucking the empty ring moved by the moving means downward from the suction port are provided.

[Effect]

Therefore, according to the present invention, the cut end of the empty ring cut by the cutting device at the end of sewing is moved by the moving means to the cloth feeding side rather than the needle drop point, and when the suction device is operated in this state, The cut end of the hollow ring passes through the suction port on the work cloth support surface and is sucked below the work cloth support surface.

〔Example〕

Hereinafter, one embodiment embodying the present invention will be described in detail with reference to the drawings. As shown in FIGS. 6 and 7, a needle bar 2 equipped with a needle 2a is supported on an arm 1 of the sewing machine so as to be movable up and down, and a needle bar 2 with a needle 2a is supported on a work cloth support surface 3a of a bed section 3. A throat plate 6 having a through hole 6a, a throat plate pawl 6b for forming a thread ring, and an opening 6C for a feed dog is attached. The feed dog 7 is retracted onto the throat plate 6 through the feed dog opening 6C.
In cooperation with the presser foot 8, the work cloth on the work cloth support surface 3a is fed in the direction shown by the arrow in FIG.
is operated in cooperation with the louver (path shown), thereby forming an overlock stitch along the edge of the work cloth on the throat plate pawl 6b.

Also, on the fabric feed side from the needle drop point, the bed portion 3
is equipped with a cutter device 9 for cutting the edges of the workpiece cloth prior to stitch formation.

A support body 11 having an air passage 10 extending substantially along the cloth feeding direction is mounted on the bed portion 3 on the cloth feeding side of the needle drop point, and its upper surface is covered with a cover 12. A tube body 13 connected to the rear end of the air passage 10 on the cover 12 has a first jet which generates an intake air flow in the air passage 10 to suck in the hollow ring R of the yarn connected to the end of the work cloth. The pipe 14 is connected at a predetermined interval to a second jet pipe 15 that generates a jet air flow in the air passage 10 for blowing back the empty ring R toward the cloth feeding side, and the first jet pipe 14 is supported. It is connected near the rear end of the body 11. A suction device is constituted by the air passage 10° pipe body 13 and the first ejection pipe 14, and the air passage 10
．． The pipe body 13 and the second ejection pipe 15 constitute a moving means.

The needle side opening 10 of the air passage 10 inside the cover 12
A fixed blade 16 is disposed at a, and a movable blade 17 is disposed so as to be reciprocally movable, and the first hollow ring cutting device 18 is constituted by both 16° 17. And air passage lO
The empty ring R sucked into the movable blade 17 is cut by cooperation with the fixed blade 16 as the movable blade 17 reciprocates. The first empty ring cutting device 18 has the same configuration as that described in Publication of Utility Model Publication No. 58-22705 (published on May 14, 1988) by the same applicant as this application. If so, please refer to it.

A suction port 20 is formed in the needle plate 6 on the cloth feeding side from the needle drop point, and the suction port 20 is formed in the needle plate 6, and
As shown in FIG. 5, a suction passage 21a is located below the throat plate 6.
A block body 21 is arranged, and its suction passage 21
The upper end opening 21b of a is arranged opposite to the suction port 20, and the lower end thereof is connected to a suction pipe 22. Then, due to the suction airflow generated in the suction passage 21a by the ejection pipe 22a connected to the suction pipe 22, the cut end of the hollow ring R is sucked into the suction passage 21a through the suction port 20 and the opening 21b. Ru.

A second ring cutting device 23 is disposed between the block body 21 and the throat plate 6. As shown in FIG. 5, the fixed blade 24 of the second hollow ring cutting device 23 has a substantially L-shaped plane, and is fixed to the upper part of the block body 21 by a plate 25. Further, the fixed blade 24 is formed with a blade portion 24a extending along the rear edge of the suction port 20. Above the fixed blade 24 is a block body 21 that extends in the cloth feeding direction with a slide piece 26C having a movable blade 26 attached to its lower surface.
The blade part 2 of the fixed blade 24 is arranged to be reciprocally movable by being slidably engaged with the guide groove 21C of the fixed blade 24.
A blade portion 26a for cutting the cut end of the hollow ring again is formed by cooperation with the cut end portion 4a.

As shown in FIGS. 2 and 3, below the movable blade 26, on the left side of the block body 21, an L-shaped rotating lever 27 is rotatably supported at its intermediate portion, and one end of the lever 27 is rotatably supported. A protruding pin 27a is engaged with the forked portion 26b of the movable blade 26. A piston 28a of an air cylinder 28 is connected to the other end of the rotary lever 27 via connecting rods 29a, 29b, and the piston 28a is connected to the other end of the rotating lever 27 via the connecting rods 29a, 29b and the rotating lever 27 based on the protruding and retracting movement of the piston 28a. Movable blade 26
is moved back and forth.

As shown in FIGS. 1(a), (b), and FIG.
It is supported slidably along the cloth feeding direction by a pair of step screws 32 and 33 passing through 0a, and a fixed blade 2 is installed at the rear of the screw.
A clamping piece 30b extending above 4 is integrally formed. Usually, due to the biasing force of the coiled spring 34, the hollow ring clamping body 30 is placed in a standby position where the rear end of the elongated hole 30a engages with the rear step screw 33, and the clamping piece 30b is attached to the fixed blade 24. It is arranged above the blade part 24a. On the other hand, a pressing piece 35 is fixed to the upper surface of the movable blade 26 for clamping the cut end of the empty ring between it and the clamping piece 30b, and its tip is arranged to protrude to the rear side of the blade part 26a of the movable blade 26. has been done.

Then, due to the forward movement of the pressing piece 35 in conjunction with the forward movement of the movable blade 26, the cut end of the empty ring is clamped between the tip of the pressing piece 35 and the clamping piece 30b, and then resists the biasing force of the coiled spring 34. When both of them are moved together by the amount of protrusion of the pressing piece 35, the blade portion 26a of the movable blade 26 overlaps the blade portion 24a of the fixed blade 24, and the cut end of the empty ring becomes the clamped portion. It is re-cut below.

Subsequently, the clamping position of the cut end of the empty ring is moved to the rear of the rear edge of the suction port 20, and the front end of the elongated hole 30a is engaged with the stepped screw 32 to restrict its movement. At this time, the cut end of the hollow ring is bent backward, tension is applied to the hollow ring R, and the width of the hollow ring is narrowed.

As shown in FIGS. 1(a) and 1(b), an adjustment plate 36 is attached to the upper part of the needle plate 21 so that its position can be adjusted along the cloth feeding direction. An opening 37 having substantially the same shape as the suction port 20 is formed in the upper bent piece 36a inserted therebetween. block body 21
The front end bifurcated portion 36b of the adjustment plate 36 is fitted into the adjustment screw 38 screwed onto the front surface of the block body 21, and the right side surface of the block body 21 is fitted into the elongated hole 39 formed in the intermediate portion 36C of the adjustment plate 36. The guide screw 40 screwed into is pushed through, and the guide screw 40
By adjusting the amount of protrusion of the adjusting screw 38 with the opening 37 loosened, the arrangement position of the opening 37 is changed from the position shown in FIG. 1(a) to the front, and the rear edge of the opening 37 and the empty ring are The engagement position with the cut end is moved forward, and the suction port 20
The ring path from the rear edge to the position where the ring holding member 30 and the like hold the ring is extended. Therefore, the entire path length of the empty ring R from the needle 2a to the clamping position is extended.

Next, the operation of the overlock sewing machine configured as described above will be explained. When the sewing machine is operated with the work cloth placed on the work cloth support surface 3a being pressed against the feed dog 7 by the presser foot 8, the work cloth moves in the direction of the arrow in FIG. After being transported and having its edges cut by the cutter device 9, a stitch is formed by the cooperation of the needle 2a and the looper at the needle drop point. When the sewing up to the cloth feeding side end of the work cloth is completed, an empty ring R is formed which is connected to the work cloth at one end and connected to the needle 2a via the throat plate pawl 6b at the other end. When the air ring R reaches a predetermined length, a suction air flow is generated in the air passage 10 by the air ejected from the first ejection pipe 14, and based on this, the air ring R is sucked into the air passage 10. Ru. Then, the loop R is cut off from the work cloth by the first loop cutting device 18, which is always operated while the sewing machine is operating.

Next, the operation of the sewing machine is stopped at the recording position, the presser foot 8 is raised, and the air jetting operation from the first jetting pipe 14 is stopped, and then the air passage 1 is discharged from the second jetting pipe 15.
Air is ejected into 2a, thereby blowing the cut end of the empty ring back toward 2a. Subsequently, when the suction pipe 22 forms an intake air flow within the suction passage 21a,
The cut end of the empty ring passes through the suction port 20 of the throat plate 6 and enters the suction passage 2.
It is sucked into 1a.

Thereafter, when the piston 28a of the air cylinder 28 is protruded and the rotary lever 27 is rotated from the solid line position in FIG. It is moved to the right in (a). After the hollow ring R is pressed by the pressing piece 35 against the holding piece 30b of the hollow ring holding body 30, these 35 and 30 are integrally attached to the coiled spring 3.
During the forward movement of the empty ring holding body 30, the blade portion 26a of the movable blade 26 moves forward against the urging force of the fixed blade 24.
4a, the end of the empty ring R is cut again.

Subsequently, the cut end of the empty ring is bent backward from the rear edge of the suction port 20 and held under tension.

On the other hand, if the arrangement position of the adjustment plate 36 is adjusted prior to this cutting operation and the opening 37 is located at a position spaced forward from the suction port 20, the opening 37 is adjusted according to the amount of separation. The engagement position between the rear edge and the cut end of the hollow ring is changed, and the hollow ring holding body 3 is moved from the rear side edge of the suction port 20.
The empty ring path leading to the clamping position by the zero etc. is extended. Therefore, the remaining amount (sewn-in length) after the empty ring is re-cut can be adjusted.

After that, when a new work cloth is placed on the work cloth support surface 3a and a sewing operation is performed, the above-mentioned empty ring R is moved between the needle 2a and the empty ring holding body 30 as the work cloth is fed. When it is sewn into the edge of the workpiece cloth in a tensioned state, and just before the end of the sewing operation, the piston 28a of the air cylinder 28 is retracted and the movable blade 26 and the pressing piece 35 are moved back together. , the empty ring holding body 30 separates from the pressing piece 35. Therefore,
There is no risk that the sky 111R will protrude from the seams and spoil the aesthetic appearance.

As described above, in this embodiment, in order to hold the cut end of the hollow ring on the cloth feeding side rather than the needle drop point, the air is drawn downward through the suction pipe 22 through the suction port 20 of the throat plate 6. Since the cut end of the ring is sucked in, there is no need to provide a member that protrudes above the work cloth support surface, and operations such as placing the work cloth on the work cloth support surface and applying feed can be performed smoothly. I can do it.

Note that this invention is not limited to the above embodiments,
Omitting the second hollow ring cutting device 23, the hollow ring holding body 30, etc.,
It is also possible to simplify the configuration.

〔Effect of the invention〕

As described in detail above, this invention eliminates the need to provide a member that protrudes above the work cloth support surface in order to hold the cut end of the empty ring closer to the cloth feed side than the needle drop point. It exhibits the excellent effect of being easy to handle.

[Brief explanation of the drawing]

FIG. 1(a) is a partial right side view showing the main parts of an overlock sewing machine embodying the present invention, FIG. 1(b) is a partial right side view showing the operating state of the second loop cutting device, and FIG. Fig. 2 is a partial front view, Fig. 3 is a partial left side view, Fig. 4 is a partial plan view, Fig. 5 is a partially exploded perspective view, Fig. 6 is a left side view of the overlock sewing machine, and Fig. 7 is an overlock sewing machine. It is a top view of a lock sewing machine. 3a...Working cloth support surface, 10...Air passage, 13.
... Pipe body, 14 ... First ejection pipe (10, 13.1 above)
4 constitutes a suction device), 15... A second ejection pipe constituting a moving means together with 10.13 above, 1
8... First empty ring cutting device, 20... Suction port, 22
. . . Suction pipe, 22a . . . Ejection pipe that constitutes a suction device together with the above 22, R . . . Empty ring. Patent applicant Brother Industries, Ltd. Agent
Patent Attorney On 1) Hironobu Diagram 2

Claims (1)

[Claims] 1. A suction device (10, 13,
14), and a cutting device (18) that cuts the empty ring (R) of the thread sucked by the suction device (10, 13, 14).
an overlock sewing machine comprising: a moving means (10, 13, 15) for moving the cut end of the empty ring (R) cut by the cutting device (18) to the fabric feeding side from the needle drop point; A suction port (
20), and a suction device (22, 22a) for sucking the empty ring (R) moved by the moving means (10, 13, 15) downward from the suction port (20). An overlock sewing machine that allows back tack sewing.