JPH0528159B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is attached to an overlock sewing machine,
This overlock sewing machine cuts the empty ring that is created next to the seam formed on the edge of the fabric, leaving the required length on the sewing machine side, and the empty ring that remains on the sewing machine side is inserted into the seam of the next fabric. This invention relates to an empty chain sewing device for an overlock sewing machine.

[Conventional technology]

As recently disclosed in JP-A-53-128443, etc., an empty ring sewing device attached to an overlock sewing machine sucks the empty ring connected to the seam formed on the fabric from the rear side of the needle drop. Suction is drawn into the suction tube, the hollow ring is cut from the sewing machine side using a cutter installed in the opening of the suction tube, and the free end of the hollow ring remaining on the sewing machine side is moved to the front side of the needle drop by wind pressure. After moving the empty ring and sucking the free end of the empty ring thus moved by the empty ring free end suction unit,
The empty ring holding section provided on the working surface of the cross plate is operated to grip the free end of the empty ring, thereby holding the empty ring left on the sewing machine side on the upper surface of the throat plate, and removing the ring from the sewing machine. A method has been proposed in which an empty ring is sewn into the seam of the next fabric to prevent the seam from fraying at the beginning of the sewing without the need for special bar-tacking work.

In the conventional device disclosed in the above-mentioned Japanese Patent Application Laid-open No. 53-128443, as shown in FIG.
The air blown out through blows away the empty ring Ch remaining on the sewing machine side in the direction intersecting the sewing axis X indicated by the arrow R, thereby removing the empty ring Ch.
The free end of Ch was moved to the part on the near side of the needle drop where the clamping part 104 was installed.

[Problem that the invention seeks to solve]

However, in the conventional device as described above, the air blown out from the nozzle 102 suddenly creates an air ring.
In order to move the free end of Ch to the holding part 104 on this side of the needle drop, it is necessary to blow out a considerably strong wind force and a large amount of air from the nozzle 102. Moreover, since the nozzle 102 is oriented in a direction intersecting the sewing axis X on the rear side of the needle drop section 103, the air blown out from the nozzle 102 directly hits the left arm of the worker. Therefore, there is a problem in that workers are repeatedly exposed to cold air during long hours of work, which is not good for their health, especially in winter.

The present invention has been made in view of the above-mentioned circumstances, and has an object to move the free end of the empty ring remaining on the sewing machine side to the side of the empty ring holding part on the near side of the needle drop part without exposing the operator to air. The object of the present invention is to provide an empty chain sewing device for an overlock sewing machine that can perform the following operations.

[Means for solving problems]

In order to achieve the above object, the empty ring sewing device for an overlock sewing machine according to the present invention connects a blow pipe to a suction device that sucks the empty ring connected to the fabric behind the needle drop, and An air outlet is provided on the cross plate diagonally in front of the suction hole of the device and diagonally behind the empty ring holding part, and after the air ring is cut in the suction hole. Suction of air by the suction device is stopped, and then the free end of the empty ring remaining on the sewing machine side is discharged from the suction hole by the air sent through the blow pipe, and the discharged empty ring is blown out from the air outlet. This feature is characterized in that the ring is moved toward the empty ring holding portion by air.

[Operation] By doing the above, the empty ring that was cut in the suction hole of the suction device and remaining on the sewing machine side is discharged from this suction hole by the air blown from the blow pipe, and is discharged from this suction hole. The empty ring moved toward the empty ring holding part by air blown out from the air outlet provided on the cross plate.

〔Example〕

Hereinafter, the present invention will be explained based on the illustrated embodiments.

1 to 2F, reference numeral 1 denotes a cross plate of an overlock sewing machine, and a throat plate 2 is fitted into a working surface 1a of the cross plate 1 at a position corresponding to a sewing machine needle. This throat plate 2 is fixed to a bracket 171 attached to the sewing machine main body M by bolts 3, and its upper surface forms a part of the working surface 1a. Further, the throat plate 2 is formed with a needle drop part 4 that vertically penetrates the working surface 1a, and moves rearward (in the direction of arrow B in the figure) from a portion adjacent to the needle drop part 4 as a starting point. An extending tongue 5 is integrally formed. Furthermore, the second
The symbol X indicated by a dashed line in FIGS. A to 2F is the sewing axis of this overlock sewing machine, which coincides with the direction in which the cloth is fed through the needle drop portion 4.

On the tongue bar 5 side with respect to the sewing axis X and at the needle drop portion 4
A recess 6 whose side parallel to the sewing axis A clamping plate 7 whose upper surface is on the same plane as the working surface 1a and forms a part of the working surface 1a is fitted therein.

The clamping plate 7 fits into a second clamping plate 72 formed in an L-shape when viewed from above, along the bottom side and one front side of the recess 6, and an L-shaped corner of the second clamping plate 72. These first clamping plates 7
1 and the second holding plate 72 are normally connected to the sewing axis X.
It is in close contact with the parallel sides.

The first holding plate 71 includes a cross plate 1
Arm portion 71a extending toward the front side of the sewing machine through the lower part of
On the other hand, as shown in FIG. 3, the second clamping plate 72 has an arm portion 71a integrally formed with the first clamping plate 71, which passes further below and extends toward the front side of the sewing machine. Extended arm portion 71
An arm portion 72a that makes sliding contact with the arm portion 72a is integrally formed with the arm portion 72a. The first clamping plate 71 and the second clamping plate 72 are rotatably attached to an auxiliary bracket 172 bolted to the bracket 171 by bolts 17 passing through the respective arm portions 71a and 72a. In addition, in Fig. 3, 118
is a torsion spring wrapped around the bolt 17,
One end of this torsion spring 118 comes into contact with an arm portion 72a that is integral with the second clamping plate 72, and urges the second clamping plate 72 and throat plate 2 to come into close contact with each other.

A cylindrical operation stud 71c is protruded from the lower surface of the first holding plate 71. Further, a rod 2 passes through the bracket 171 and the second holding plate 72 in a direction perpendicular to the sewing axis X.
An engaging member 22 is attached to one end of 1. Then, this engaging member 22 is attached to the operating stud 71.
By engaging with the first holding plate 71, the first holding plate 71 can be rotated by operating the rod 21. A male thread is provided on the protruding portion of the rod 21 from the bracket 171, and a spring receiver 23 is screwed into this male thread. Then, this spring receiver 23 and the bracket 1
A compression spring 24 is tensioned between the first clamping plate 71 and the second clamping plate 7 which are engaged with the rod 21 by the biasing force of the compression spring 24.
2 (direction of arrow C in the figure). On the other hand, a first air cylinder 20 is disposed below the cross plate 1, and when the piston rod 20a of the first air cylinder 20 is retracted, the first holding plate 71 is attached to the piston rod 20a of the first air cylinder 20. The rod pressing member 25 contacts or approaches the tip of the rod 21 in a state where the rod is in close contact with the second holding plate 72.
is attached. By extending the piston rod 20a, the first air cylinder 20 causes the rod pressing member 25 to press against the rod 21.
is attached at a position where it can be pressed against the biasing force of the compression spring 24.

With the above configuration, the first holding plate 7
1 can be independently escaped from the recess 6 by a rotation movement using the bolt 17 as a rotation axis, and thereby, as shown in FIG. An insertion opening H at the free end of the empty ring can be formed between the two.

On the other hand, the second holding plate 72 is driven by the second air cylinder 27 installed at the lower part of the cross plate 1 as a driving source. That is, the piston rod 27a of the second air cylinder 27, which moves forward and backward in the vertical direction, is brought into contact with the rod receiver 28b formed at one end of the L-shaped swinging arm 28, and
By bringing the other end of the swinging arm 28 into contact with the arm portion 72a of the second clamping plate 72, extending the piston rod 27a and pushing up the rod receiver 28b, the second clamping plate 7
2 can be rotated about the bolt 17 in the same direction as the first holding plate 71.

Reference numeral 8a denotes a presser foot that holds the fabric, which is a workpiece, between it and the throat plate 2, and this presser foot 8a is attached to the tip of a presser foot 8b that is pivotably supported on the sewing machine main body M on the rear side. This presser foot 8b
is oscillated by operating the air cylinder 8c, and moves the presser foot 8a up and down between the presser foot position and the presser release position.

Further, at the rear of the tongue 5, there are
As shown in Fig. F, a cloth guide 9 parallel to the sewing axis
It is installed standing up from a.

A loop cutting section 10 is provided on the back side of the guide surface of the cloth guide 9. This empty ring cutting part 10
A suction passage 11 is provided by using the back surface of the cloth guide 9 as a part of the inner wall, and the suction hole 1 of this suction passage 11 is provided.
1a is bored in the cloth guide 9 near the rear end of the throat plate 2, and a first cutter 12 is provided near the opening of the suction hole 11a.

The suction passage 11 is connected to an air suction source (not shown), and by operating this air suction source, the air ring created along the fabric is sucked through the suction hole 11a. This suction passage 11 is an air passage parallel to the sewing axis X of this sewing machine, and a suction hole 11a facing in a direction intersecting the sewing axis X is provided at the end of this air passage. Further, a small-diameter blow pipe 13 is connected to the suction passage 11 midway through the passage for feeding air under pressure to the suction hole 11a side.

The first cutter 12 includes a fixed blade 12a whose cutting edge is fixed to the rear lower end of the suction hole 11a, and a suction passage 11.
The movable blade 12b is rotatably supported on the outside of the suction passage 11 and inserted into the suction passage 11 from the upper surface of the suction passage 11.
By being driven by a member linked to the main shaft of the sewing machine, its cutting edge intersects with the cutting edge of the rigid blade 12a. Therefore, if the end of the fabric on which the hollow ring connected to the seam is formed is moved backwards and the hollow ring intersects with the cutter 12, the empty ring will leave some length on the sewing machine side. disconnected. The drive of the movable blade 12b does not necessarily have to be linked to the drive of the sewing machine; for example, the number of stitches that move after the end of the fabric passes through the needle drop section 4 is counted, and this number of stitches reaches a set number. After stopping the sewing machine at this point, the sewing machine may be driven by a solenoid, or alternatively, the operator may confirm that the required length of empty ring has been created, and then drive the sewing machine by operating a pedal, etc. It's okay.

On the working surface 1a on the opposite side of the tongue 5 across the sewing axis X, which is diagonally in front of the suction hole 11a and diagonally behind the holding plate 7, there is a sewing axis X and a sewing axis X as shown in FIG. Long hole 1 parallel to parallel sewing axis
A nozzle 15a of a blow pipe 15 connected to an air supply source (not shown) bulges out from this long hole 14. This nozzle 15
The tip of the blow pipe 15 whose end is closed is bent at right angles, and an air outlet is provided in the circumferential wall of the bent tip, which is horizontally elongated in the axial direction of the pipe and opens toward the tongue 5 side. 15aa. Air outlet 1 formed in this way
The air blown out from 5aa is blown out from one end of the nozzle 15a toward the other end along the working surface 1a, and therefore, as shown by arrow _E3 in FIG. 7
Head to the side.

Nozzle 1 16 is an air outlet at the tip.
6a, the blow pipe 16 is supported by the sewing machine main body M so as to blow air toward the insertion opening H side formed by driving the first holding plate 71. ing.

A second cutter 30 is disposed between the tongue 5 and the clamping plate 7, and includes a fixed blade 30a and a movable blade 30b, each having a cutting edge parallel to the sewing axis X. As will be described later, this second cutter 30 is provided to cut an empty ring that intersects with this second cutter 30 by driving the second holding plate 72.

Note that 31 is a cloth detection sensor that detects the presence or absence of cloth.

Next, the operating procedure of the above-mentioned empty ring sewing device will be explained.

First, in the hollow ring cutting section 10, the hollow ring connected to the end of the fabric is cut off from the fabric. That is, when the sewing machine is driven, the air suction source connected to the suction passage 11 is activated, and the suction passage 11
Air is sucked into the chamber as shown by arrow _E1 in FIG. 2A. Therefore, the empty ring created by connecting to the seam of the fabric is also automatically sucked into the suction hole 11a. Therefore, as shown in FIG. 2A, if the end of the fabric N is moved to the rear side of the suction hole 11a and the empty ring Ch intersects with the first cutter 12, this empty ring Ch will be placed on the sewing machine side. It is cut from the fabric N leaving a substantially constant length. An empty ring remains on the sewing machine side after being cut in this way.
The free end of Ch is the fixed blade 12a of the first cutter 12.
The suction hole 11a does not intersect with the movable blade 12b.
The liquid is sucked into the suction passage 11 through the front side of the tube.

With the free end side of the thus cut empty ring Ch being sucked into the suction passage 11, the driving of the sewing machine is stopped, and the presser foot 8a is pressed by stepping back on the footboard (not shown) of the sewing machine, etc. to rise.

Next, the operation of the air suction source connected to the suction passage 11 is stopped, and air is pumped through the blow pipe 13. The air forced from this blow pipe 13 is sent to the suction hole 11a side as shown by the arrow _E2 in FIG. 2B, but since the suction passage 11 is parallel to the sewing axis X, this suction passage Air discharged from the suction hole 11a opened on the side of the housing 11 heads diagonally to the front side. Therefore, the empty ring remaining on the sewing machine side that was sucked into this suction hole 11a is removed from the air outlet 15 located diagonally in front of the suction hole 11a, as shown in FIG. 2B.
Pushed out before aa. In addition, blow pipe 13
The air pumped from the suction hole 11a only has to be enough to discharge the free end side of the empty ring Ch located inside the suction hole 11a to the outside of the suction hole 11a, so a large air volume is not required and the delivery time is short. It can be instantaneous. Therefore, the air pumped from the blow pipe 13 has almost no effect on the operator.

After the empty ring Ch is released from the suction passage 11 and the pressure feeding of air from the blow pipe 13 is stopped, air is blown out from the nozzle 15a of the blow pipe 15 and the first air cylinder 20 is operated to close the piston rod 20a. is stretched, and air is also blown out from the nozzle 16a of the blow pipe 16.

Since the air blown out from the nozzle 15a of the blow pipe 15 is blown out along the work surface 1a toward the holding plate 7 side as described above, the air is blown out in front of the nozzle 15a by the blow pipe 13. The free end of the empty ring Ch is now moved toward the holding plate 7 by the air blown out from the nozzle 15a. The air blown out from the nozzle 15a of this blow pipe 15 is
Since the air is directed diagonally from the opposite side of the tongue bar 5 to the front side (from the left side to the front right side of the sewing axis X in the figure) with respect to the sewing axis X, generally work with your body on the left side of the sewing axis X. It will not hit the worker.

Meanwhile, at the same time, as the piston rod 20a is extended, the first holding plate 71 rotates around the bolt 17 to open the insertion port H on the near side of the needle drop. Further, the free end of the empty ring Ch is blown into the insertion port H by the air blown down from the nozzle 16a, as shown in FIG. 2C.

When the empty ring Ch is blown into the insertion port H in this way, the drive of the first clamping plate 71 is stopped, the piston rod 20a is retreated, the insertion port H is closed, and the first clamping plate 71 is closed. An empty ring Ch is held between the second holding plates 72.
By making the time for blowing air from the nozzle 16a longer than the driving time for the first air cylinder 20, the air can be blown from the nozzle 16a even from the time the piston rod 20a begins to retreat until the insertion port H is closed. As shown in Fig. 2D, the empty ring Ch is held in place without loosening.

In addition, in order to more reliably hold the empty ring Ch without loosening, a suction pipe having an opening may be provided below the insertion port H, and may be used in combination with the blow pipe 16.

After holding the empty ring Ch as shown in FIG. 2D as described above, the presser foot 8a is moved to the throat plate 2.
Lower it to the upper cloth holder position.

Next, by operating the footboard for raising the presser foot of the sewing machine, the presser foot 8a is raised to the presser release position and the fabric (not shown) is inserted into a predetermined position, and then the presser foot 8a is lowered. This presser foot 8a
The fabric is sandwiched between the sewing machine and the throat plate 2, and in this state the sewing machine is driven to form a seam at the edge of the fabric.

In this embodiment, the presence or absence of cloth may be detected by the cloth detection sensor 31, and the movement of the presser foot 8a may be controlled via the air cylinder 8c based on the signal.

In the empty chain sewing device of the overlock sewing machine of this embodiment, when the edge of the fabric has passed through the needle drop and several stitches have been sewn, the first clamping plate 71 is moved again as shown in FIG. 2E. is rotated to release the clamping, thereby preventing the leading end of the fabric from being pulled by the empty ring and curling.

Further, in this embodiment, the second air cylinder 27 is operated to extend the piston rod 27a a predetermined time after the sewing machine is driven to form a seam. As a result, the swing arm 28 swings around the corner portion 28a,
Arm portion 72 integrally formed with second holding plate 72
a is pressed by the upper tip 28d of the swing arm 28, and the second clamping plate 72 rotates toward the first clamping plate 71. During this rotation, the second clamping plate 72 pushes the empty ring Ch toward the first clamping plate 71 as shown in FIG. 2F, and
This empty ring Ch is crossed with the second cutter 30. Therefore, the empty ring Ch is inserted between the fixed blade 30a and the movable blade 30b of the second cutter 30 and cut. As is clear from this, in the apparatus of this embodiment, by appropriately setting the timing of driving the second holding plate 72, the length of the empty ring Ch to be sewn into the fabric can be changed.

It should be noted that the present invention is of course not limited to the above-mentioned embodiment, and for example, the blow pipe 15 may be movable up and down so that it can be sunk below the work surface 1a when unnecessary. In addition, various mechanisms other than the above-mentioned embodiments can be used as the mechanism for holding the empty ring, and the processing steps for the empty ring once held can also be changed as desired. Furthermore, if the air outlet is made horizontally long as in the above embodiment, air can be blown in a widely diffused state along the work surface, and the air outlet can be moved in front of the air outlet. Although there is an advantage in that it can reliably handle even if there is a certain degree of difference in the position of the empty ring each time, in the present invention, the air outlet does not have to be such a horizontally long one,
It may be a circular outlet like a general nozzle, or a large number of small circular nozzles may be arranged side by side in the horizontal direction. However, in this case, it is necessary to direct the air outlet itself toward the empty ring holding part.

〔Effect of the invention〕

As is clear from the above description, according to the empty ring sewing device of the overlock sewing machine according to the present invention, a small amount of air is required to discharge the free end of the empty ring sucked into the suction hole of the suction device. Furthermore, since the evacuation time is instantaneous, the air blown out by the blow pipe connected to the suction device hardly ever hits the operator. Furthermore, since the air blown out from the air outlet on the cross plate is directed in the direction where the worker is not present, this air will not hit the worker either. Therefore, the worker will not be exposed to cold air repeatedly, which will damage his health.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view showing an embodiment of the empty ring sewing device of an overlock sewing machine according to the present invention, and Figs. 2A to 2F show the process of processing an empty ring by the embodiment device. A schematic plan view of the main parts, FIG. 3 is an enlarged perspective view of the empty ring holding part, and FIG. 4 is an enlarged sectional view of the main parts explaining the blow pipe.
FIG. 5 is a schematic plan view illustrating a conventional example. 1a... Working surface, 4... Needle drop part, 7... Holding plate (empty ring holding part), 11... Suction passage (suction device), 11a... Suction hole, 12... Cutting device, 1
3...Blow pipe, 15aa...Air outlet.

Claims (1)

[Scope of Claims] 1. An empty ring created in connection with a seam formed at the edge of the fabric is sucked into a suction hole of a suction device provided on the rear side of the needle drop and is cut within this suction hole. Then, the free end of the empty ring remaining on the sewing machine side is moved to the front side of the needle drop by wind pressure, this moved empty ring is clamped on the front side of the needle drop, and this clamped empty ring is attached to the next fabric. In the hollow ring sewing device of the overlock sewing machine, which is configured to sew into the seam being formed, a blow pipe is connected to the suction device, and a cross is connected diagonally in front of the suction hole and diagonally behind the hollow ring holding part. An air outlet for blowing out air is provided on the plate on the side of the empty ring holding part, and after the air ring is cut in the suction hole, suction of air by the suction device is stopped, and then air is sent through the blow pipe. The free end of the empty ring remaining on the sewing machine side is discharged from the suction hole by air,
An empty ring sewing device for an overlock sewing machine, characterized in that the discharged empty ring is moved toward the empty ring holding part by air blown from the air outlet.