JPH0747187A - Upper looper for overlock sewing machine - Google Patents

Abstract

PURPOSE:To easily mount an attachment looper and to make the position thereof stable, where the looper 13 mounted on a standing upper looper when the number of threads for overedge-stitch is varied in an overlock sewing machine. CONSTITUTION:An attachment looper 8 wherein a recessed engagement part 12 to be fitted into a base 5 for the upper looper 2 has an edge surface 12a being in contact with the side of the base 5 in the state of its engagement and an engagement piece 13 being in contact with the undersurface 5b of the base 5 in the state thereof, is provided on the upper looper 2 fastened to an upper looper shaft 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an upper looper for an overlock sewing machine which cooperates with a sewing machine needle and a lower looper to selectively perform one-needle, three-thread overedging and one-needle, two-thread overedged sewing. Regarding the device.

[0002]

2. Description of the Related Art In Japanese Utility Model Publication No. 1-35739, in the above overlock sewing machine, an upper looper for one-needle, three-thread overedge sewing is fastened to an upper looper shaft, and separately from the upper looper. An upper looper device for an overlock sewing machine is disclosed, which is provided with an attachment looper for one-needle, two-thread edge-overlock stitching, and is used by attaching the attachment looper to the upper looper at the time of one-needle, two-thread edge-overlock stitching.

Specifically, the upper looper has a thread passage hole at the tip end side through which the first lower thread is inserted at the time of one-needle, three-thread overedging, and the second looper from the lower looper. A thread hooking portion on which the lower thread is hooked is provided at an upper edge of a boundary portion between the thread operating portion and the base portion. The attachment looper has, at one end, a protrusion that engages with the thread passage hole and a thread hook portion that protrudes from the upper edge and locks the lower thread from the lower looper at the time of one-needle, two-thread overlock stitching. , A locking portion for positioning the attachment looper to the upper looper by engaging a fitting portion having a U-shaped cross section at the other end portion so as to sandwich the base portion of the upper looper and elastic unevenness on the side surface of the base portion. It has a section.

Therefore, when attaching the attachment looper to the upper looper, the fitting portion of the attachment looper is gripped with a finger and fitted into the base portion of the upper looper. At this time, the locking portion is engaged with the side surface of the base portion by elastic unevenness. Whether or not this engagement is reliable and accurate is judged by the operator's sense. Further, the tip portion of the attachment looper is once bent so that the protrusion separates from the upper looper, and the protrusion is inserted into the thread passage hole of the upper looper. In the unmounted state, the tip of the attachment looper is bent to remove the protrusion of the attachment looper from the threaded hole of the upper looper, hold the fitting portion, and pull out from the base portion of the upper looper.

[0005]

However, when the attachment looper is mounted on the upper looper, the fitting of the base portion and the fitting portion is the engagement of the side surface of the base portion and the engaging portion by elastic unevenness, Such engagement is determined by whether the unevenness is engaged when the elastic force of the fitting portion having a U-shaped cross section is large or the frictional force when fitting the fitting portion to the base portion is large. Is difficult to judge by the operator's sense. If the positioning is not performed by this engagement, the positions of the protrusions and the thread passage holes will not be aligned, and the mounting work will require labor and time.

Further, the tip portions of the attachment looper and the upper looper are mostly long plate-shaped portions having substantially the same shape, and in order to bend the tip portion of the attachment looper, pick the attachment looper with both fingers. It is a work to bend and the workability is extremely poor. Further, the engagement between the side surface of the base portion and the locking portion due to the elastic unevenness causes the unevenness to be worn and loosened when the attachment and removal of the attachment looper is repeated, the positioning function is not fulfilled, and the stability of the mounting posture is impaired. .

Therefore, according to the present invention, the attachment looper and the upper looper can be surely mounted in a positioned state by a simple work, and can be easily removed, and an overlock sewing machine which always ensures a stable mounting posture. The purpose is to provide an upper looper device.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a base portion fastened to an upper looper shaft and a first bobbin thread extending from the base portion in a direction intersecting with a locus line of a needle bar and one needle three-thread overlock stitch An upper looper comprising a thread operating portion having a thread through hole through which the second looper thread from the lower looper is hooked and a thread operating section having a thread hooking section for hooking the second lower thread from the lower looper, An elastic portion having a projection to be inserted into the through hole, a thread hooking portion projecting from the thread operating portion to an upper edge to lock the lower thread from the lower looper, and an operation piece for pushing a finger, A recessed fitting portion having an end face that is connected to the elastic portion and fits into the base portion and abuts a side surface of the base portion in the fitted state; and the base portion extending from one end of the fitting portion. Of the attachment looper having an engaging piece that abuts the lower surface of the.

[0009]

In the upper looper device of the present invention, the attachment looper in the state of being attached to the upper looper has an end surface in which a concave fitting portion that fits into the base portion abuts the side surface and the lower surface of the base portion in the fitted state. And an engaging piece. In this fitted state, the base part of the upper looper is surrounded by the concave fitting part, the end face of the fitting part, and the engaging piece from three sides, so that a stable mounting posture is always obtained. That is, in the attachment looper, the displacement of the base portion in one axial direction is restricted by the contact between the end surface of the fitting portion and the side surface of the base portion, and the displacement of the base portion in the swing direction is formed by the concave fitting portion and the engaging piece. Is regulated.

When the attachment looper is attached to the upper looper, the attachment looper is fitted to the base portion in a slightly oblique posture with respect to the upper looper.
After that, until the end face of the fitting portion contacts the side surface of the base portion and the engaging piece of the fitting portion engages with the lower surface of the base portion, the elastic portion is attached to the thread operating portion of the upper looper around the fitting portion. The operation piece on the elastic portion side may be pressed with a finger so that the attachment looper is rotated in the direction in which the two overlap. When the engagement between the end surface of the fitting part and the side surface of the base part and the engagement piece of the fitting part and the lower surface of the base part are confirmed, it means that the positioning has been done. Get involved in. When not engaged, the elastic portion is bent by the operation piece to be engaged. To remove the attachment, temporarily press the operating piece with your finger to bend the elastic part to release the engagement between the protrusion and the threading hole, and then operate in the opposite direction to the attachment release to move the attachment looper. Just rotate it.

[0011]

As described above, according to the present invention, the concave fitting portion that fits into the base portion of the upper looper is fastened to the upper looper shaft by the side surface of the base portion in the fitted state. Since an attachment looper having an end surface that abuts on the base and an engaging piece that abuts on the lower surface of the base is provided, after the fitting part is partially fitted to the base, the end face of the fitting is located on the side surface of the base. If the attachment looper is rotated around the fitting part until it comes into contact with the bottom surface of the base part, and the engaging piece of the fitting part contacts the lower surface of the base part,
The attachment looper can be attached to the upper looper, and it can be easily determined whether or not it is in a normal attached state, and the positional relationship between the protrusion and the thread passage hole is guaranteed, making it easy to engage them and attaching it to the upper looper of the attachment looper. The labor required for the work can be reduced and the wearing can be performed in a short time.

Further, according to the embodiment of the present invention, in which the base portion of the upper looper is surrounded by the concave fitting portion and the end surface of the fitting portion and the engaging piece from three sides, the attachment looper has the one axial direction of the base portion. And the displacement in the swinging direction of the base are regulated, and there is no part that loosens even if the attachment and detachment is repeated, and a stable mounting posture can always be maintained.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an upper looper device for an overlock sewing machine according to the present invention will be described below in detail with reference to FIGS. In the upper looper device of the overlock sewing machine of this embodiment, as in the conventional case, the upper looper shaft 1 is fastened with the upper needle 2 for one-needle, three-thread overedging, and separately from the upper looper 2. An attachment looper 8 for one-needle two-thread overedging is provided.

The upper looper 2 mainly comprises a base portion 5 and a thread operating portion 2a extending from the base portion 5 in a direction intersecting with a locus line (not shown) of the needle bar, and the thread operating portion 2a has a plate. A thread hooking portion 4 is formed by a step between the thread passage hole 3 in the thickness direction and the base portion 5 at the upper edge, and the base portion 5 is a part of the base portion 5 and is fastened so as to be orthogonal to the upper looper shaft 1. Has a flange portion 6 As shown in FIG. 4, the flange portion 6 has a mounting shaft 6 a that extends further and is inserted and fixed to the upper looper shaft 1.

The attachment looper 8 has a projection 7 that is engaged with the thread passage hole 3 and projects from the thread operating portion 2a to the upper edge so that the lower thread a from the lower looper (FIG. 7).
An elastic portion 11 including a thread hooking portion 9 to which the thread is hooked and a finger pushing operation piece 10 extending at a right angle behind the thread hooking portion 9, and a concave shape (a U-shaped section in cross section) continuously provided with the elastic portion 11. ) Fitting part 12
An engaging piece 13 extending from the lower end side of one piece of the fitting section 12 and engaging with the lower surface 5b of the base section 5, and a gripping piece 14 formed on the other piece of the fitting section 12. Consists of. The fitting portion 12 is configured such that the rear end surface 12a of one piece is brought into contact with the side surface 5a (FIG. 3) of the flange portion 6 while being fitted to the base portion 5.

In the upper looper device having such a structure, when the overlock sewing machine is used for one-needle, three-thread overedge stitching, as shown in FIG. 6, an attachment looper for one-needle, two-thread overedge stitches is used. 8 is removed from the upper looper 2, the first lower thread b is inserted through the thread passage hole 3 of the upper looper 2, the second hook thread a from the lower looper is hooked on the thread hooking portion 4 of the upper looper 2, and the needle shaft To work with. Further, when using for one-needle two-thread overedging, as shown in FIG. 7, the attachment looper 8 is attached to the upper looper 2, and the thread hooking portion 9 is hooked with the lower thread a from the lower looper, Cooperate with the needle shaft.

Attachment looper 8 to upper looper 2
When attaching, the attachment looper is held in a slightly oblique posture with respect to the upper looper 2 (in this case, the gripping piece 14 is used), and the base portion 5 is inserted into the fitting portion 12. As described above, the base portion 5 is fitted to the fitting portion 12 by moving as it is. When the base portion 5 is fitted into the fitting portion 12, a resistance is generated in the fitting operation due to a slight elastic force and frictional action of the fitting portion 12, but if the fitting amount is deepened as it is, the fitting portion 12 The rear end face 12a of 12 is the flange 6
To the side surface 5a of the. At this time, as shown in FIG. 5, the operation piece 10 is continuously pressed downward with one finger to move the thread operation portion 2a.
Attachment looper 8 so that elastic part 11 overlaps
Rotate. This rotation operation is performed until the engagement piece 13 contacts the lower surface 5b of the base 5, as shown in FIG. Thus, the attachment looper 8 is positioned on the upper looper 2. After the above positioning, when the protrusion 7 is not engaged with the thread passage hole 3, the elastic portion 11 is once bent by the operation piece 10 and the force applied to the operation piece 10 is released as it is.
Securely engages the threading hole 3. In the non-wearing state, the attachment looper 8 is operated by the operation piece 10 in the opposite direction to the above.
Can be rotated.

Therefore, according to this embodiment, the end face 12a of the fitting portion 12 and the side surface 5a of the base portion 5 are brought into contact with each other and the engaging piece 13 is provided.
The normal attachment state of the attachment looper 8 to the upper looper 2 can be reliably determined by abutting the lower surface 5b of the base 5 and the attachment operation of the attachment looper to the upper looper can be performed very simply. Further, in the upper looper device, the attachment looper 8 is configured such that the end surface 12a and the engaging piece 13 respectively contact the side surface 5a and the lower surface 5b of the base 5 in the mounted state,
The movement of the base 5 in the one axis direction is restricted, and the movement of the base 5 in the swinging direction is restricted by the concave fitting portion 12 and the engagement piece 13, so that there is no part that is loosened even if the attachment / detachment is repeated. You can always maintain a stable wearing posture.

[Brief description of drawings]

FIG. 1 is a perspective view showing an upper looper device of an overlock sewing machine according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state before the protrusion of the attachment looper according to the present invention is engaged with the thread hole of the upper looper.

FIG. 3 is a perspective view showing an upper looper of the present invention.

FIG. 4 is a cross-sectional view showing the fastening structure of the upper looper of the present invention.

FIG. 5 is a perspective view illustrating a method of attaching and detaching the attachment looper of the present invention.

FIG. 6 is a perspective view showing a mode of use of the one-needle, three-thread overedging according to the present invention.

FIG. 7 is a perspective view showing a mode of use of the present invention at the time of one-needle, two-thread overedging.

[Explanation of symbols]

1 ... Upper looper shaft, 2 ... Upper looper, 3 ... Thread passage hole, 4 ...
Threading portion, 5 ... Base portion, 5a ... Side surface, 5b ... Lower surface, 6 ... Flange portion, 7 ... Projection, 8 ... Attachment looper, 9 ...
Threading portion, 10 ... Operation piece, 11 ... Elastic portion, 12 ... Fitting portion,
12a ... end face, 13 ... engaging piece.

Claims (1)

[Claims] 1. A base portion fastened to an upper looper shaft, a thread passage hole extending from the base portion in a direction intersecting with a locus line of a needle bar and through which a first lower thread is inserted at the time of one-needle three-thread edge overlock stitching, An upper looper including a thread operating portion having a thread hooking portion for hooking a second lower thread from the lower looper, and a projection that is engaged with the thread through hole during one-needle / two-thread overlock stitching, An elastic portion having a thread hooking portion projecting to the upper edge from the thread operating portion and hooked with the lower thread from the lower looper, and an operating piece for finger pushing, and an elastic portion that is connected to the elastic portion and is fitted to the base portion. And a concave fitting portion having an end face that abuts a side surface of the base portion in the fitted state, and an engaging piece that extends from one end of the fitting portion and abuts a lower surface of the base portion. Attachment looper, upper looper device for overlock sewing machine.