JPH022299Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] An overlock sewing machine automatically sucks in an empty ring, and when sewing the empty ring around it, clamps it to the extent that it gives a slight tension to the sucked-in empty ring. This relates to a device for

[Prior art] Conventional overlock sewing machines use a lower wrapping method in which the empty ring is blown away from the front and is mechanically wrapped around the underside of the fabric for sewing. When sewing by suction and winding, the top winding method was used, in which the pipe moved in front of the needle drop, or the top winding method, in which the empty ring was sucked in by a vacuum in front of the needle, and the pipe moved back and forth.

[Problems to be solved by the invention] In the conventional sewing method, the appearance and feel of the stitches that are sewn by sucking in or blowing away the hollow ring are not good, and the ring-wrapping stitch is not good. The seams could not be finished well unless some tension was applied.

For this reason, tension was applied using a mechanical device, but this was extremely inconvenient to handle.

Furthermore, it lacked continuous operation performance and was difficult to automate.

[Means for Solving the Problem] In the device for applying tension to an empty ring according to the invention of this application, in front of the sewing section of the sewing machine in the cloth feeding direction,
The vacuum ring is sucked into the vacuum passage from the opening of the vacuum pipe, and the vacuum ring is held within the vacuum ring clamping casing by electromagnetic adsorption force, thereby imparting appropriate tension to the vacuum ring. And so.

[Operation] In the device for applying tension to a hollow ring according to the invention of this application, a hollow ring is created by empty stitching a predetermined number of stitches using an empty ring holding timer, and then the fabric is sucked into a pipe by a vacuum to detect the presence of cloth. At times, by adhering a magnet to the armature, sewing of the empty ring is started in a state in which tension can be applied while the empty ring is held and sewn in.
The sewing machine stops after completing the specified sewing.

Next, the thread breaks and one step of sewing is completed. Subsequently, the process moves to the next step of sewing, in which a predetermined number of empty stitches are performed to create an empty ring.

[Example] An example of an apparatus for applying tension to an empty ring according to this invention will be described based on the drawings.

As shown in FIG. 1, a vacuum ring suction pipe 2 is provided on the side surface of the presser arm 1, and a vacuum ring holding casing 3 is provided in the middle thereof.
That is, the vacuum pipe 2 is connected to the front and rear of the connecting pipe piece 4 of the casing 3. A presser foot 5 is provided at the front end of the presser arm 1, and a front open end 6 of a vacuum pipe is provided at the upper part of the presser foot 5 in front of the needle drop.

The rear part of the vacuum pipe 2 is connected to a vacuum device (not shown).

The structure of the hollow ring clamping casing 3 will be explained based on FIG.

The structure of the hollow ring holding casing 3 is such that a support body 7 is provided in the center of the casing, and vacuum pipe pieces 4 are provided at the front and rear of the support body 7 and are connected to the vacuum pipe 2.

An excitation coil 8 and an armature 9 are attached to one side of the support 7 perpendicular to the vacuum passage, and an air ring clamping plate 10 is provided at the end of the armature 9 on the passage side. teeth,
It faces the vacuum passage in the support 7.

A guide shaft 11 having a flat plate at both ends is movably supported on the other side of the support body 7, and the flat plate on the side of the vacuum passage has a guide shaft 11 with a vacuum passage in between.
A magnet 12 is provided opposite the holding plate. Further, a coil spring 13 is installed between the flat plate at the other end of the guide shaft 11 and the support body.

Next, the implementation steps will be described based on the flowchart of the steps shown in FIG.

The overlock sewing machine equipped with the empty ring clamping device according to the invention of this application is turned on, and data is set in the empty ring clamping timer.

The data to be set include the time for empty ring clamping and reset, the time for empty ring suction and suction stop, etc.

When the sewing machine starts, a predetermined number of empty loops are created by empty stitching, and then the sewing machine stops.

When presser 5 is raised, the air ring suction is turned on.
Therefore, the empty ring is sucked into the vacuum pipe 2.

When the fabric to be sewn is set and the presser foot 5 is lowered, the presence of fabric is detected, so the empty ring clamping device 3
The armature 9 is excited with a positive current, and as a result of this action, the clamping plate 10 attracts the magnet 12, so that sewing begins with the empty ring clamped.

The holding of the empty ring and the suction of the baguette combine to give the empty ring an appropriate tension, so that the empty ring connected to the edge of the fabric is sewn into the seam at the front edge of the fabric.

As the sewing continues, the empty ring slips out from the clamping plate 10, and the holding of the empty ring becomes time-up, and a reverse current is passed through the excitation coil 8, and a repulsive force is generated in the armature 9, which is in contrast to the restoring force of the return spring 13. Eventually, the magnet 12 returns to its original position and the clamping device 3 is reset.

Until the empty ring slips out of the clamping plate 10 and exits from the vacuum pipe opening 6, the empty ring is sewn into the hollow ring under tension due to the suction action of the vacuum tube.

As the sewing continues, the empty ring slips out of the vacuum pipe opening 6, and the prescribed sewing continues in that state. When the sewing machine stops, the "thread cutter" is turned "ON", the thread is cut, and the sewing machine is turned "OFF".

This completes one step of sewing, but the next step continues and a predetermined empty stitch is performed to create an empty ring.

In this way, continuous automatic sewing with empty ring wrapping is carried out.

In addition, if the strength of holding the empty ring is changed depending on the type of yarn forming the empty ring, this can be done appropriately by adjusting the strength of the voltage of the excitation coil 8.

[Other Examples] The structure of the empty ring clamping device is such that the armature moves back and forth with respect to the excitation coil, and when the current is turned on and
It is also possible to reciprocate the armature by turning it off, etc., and to sandwich the empty ring between the support wall or casing wall across the vacuum passage.

[Effects] Since the device of this invention is an empty ring clamping device that utilizes electromagnetic action, it is small and lightweight, and can be attached to the presser arm.

Furthermore, the tension applied to the empty ring can be adjusted by adjusting the strength of the voltage of the current to the electromagnetic coil. Therefore, the finish of the loop-wrapping seam was extremely good.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a state in which the device according to the invention of this application is attached to a presser arm. FIG. 2 is a sectional view of the empty ring clamping casing of this device. FIG. 3 is a flowchart of the process of implementing an overlock sewing machine equipped with the device according to the invention of this application. Note that the symbols in the figure are as follows. 1
...Holding arm, 2...Bakyum pipe, 3...
Empty ring clamping casing, 4... Connecting pipe piece, 5
... Holder, 6 ... Vacuum pipe front opening end, 7 ... Support body, 8 ... Excitation coil, 9 ... Armature, 10 ... Empty ring holding plate, 11 ... Guide shaft, 12 ... Magnet, 13 ……coil spring.

Claims (1)

[Claims for Utility Model Registration] 1. An empty ring holding casing is provided in the middle of an empty ring suction vacuum pipe that is installed parallel to the presser arm of an overlock sewing machine, and within the casing, a suction force is applied by electromagnetic action. A device for applying tension to a hollow ring, which is characterized by clamping the hollow ring which is being sucked into the air. 2. In carrying out the invention described in paragraph 1, the structure of the hollow ring holding casing is such that a support is provided in the center of the casing, pipe pieces for connection to the vacuum pipe are provided before and after this support, and the vacuum passage is An electromagnetic coil is fixedly installed on one side perpendicular to the passage, and the magnet installed on the other side can be attracted or repelled by the attraction force of the armature at the center of this coil. A device that applies tension to the empty ring of the structure.