JP2543578Y2 - Overlock sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application field] The present invention relates to an overlock sewing machine, and more specifically, a single needle and three needles which are formed by three threads passed through an upper looper, a lower looper and a needle. The present invention relates to an overlock sewing machine capable of switching overlock stitching of a thread, and overlock sewing of a single needle and two threads performed by a lower looper and two threads passed through a needle.

[Related Art] Conventionally, in order to prevent the sewing cloth from fraying, the overlock stitching of three needles and three threads is performed.
When the overlock stitching is performed by the overlock stitching of the book, wrinkles are generated and the appearance is impaired, so that the overlock stitching of the single needle and the double thread is performed. Various overlock sewing machines have been considered in order to be able to switch overlock stitching of one needle and three threads and edge overlocking of one needle and two threads with one sewing machine. 2. Description of the Related Art A sewing machine having a configuration in which a lower looper is detached from an upper looper shaft and a key looper is attached when performing overlock stitching of a single needle and two threads is known.

In such a sewing machine, the upper looper and the key looper must be replaced every time the sewing machine is switched.
In the overlock sewing machine described in Japanese Patent Publication No. 48, after rotating the looper claw provided on the upper looper mounting base, the looper claw is moved along the rotation center line, and the tip thereof is inserted into the thread hole of the upper looper. The key looper is formed by the engagement, and the overlock sewing of the single needle and the two threads is performed.

[Problem to be Solved by the Invention] In such a conventional overlock sewing machine, a rotation operation of a looper claw and a movement operation of engaging the looper claw with a thread hole are required to form a key looper. Therefore, Japanese Patent Application Laid-Open No. 58-27586 discloses that the upper looper position is moved to a corresponding position in accordance with the switching between the overlock stitching of the single needle and three threads and the overlock stitching of the one needle and two threads. A structured overlock sewing machine is disclosed. However, in this type of overlock sewing machine, the upper looper must be moved to a corresponding position in accordance with the switching, and there is a disadvantage that the entire sewing machine has a complicated configuration.

Japanese Patent Laid-Open Publication No. Sho 60-129079 discloses that a key looper is formed by moving an engaging plate so that its tip is engaged with an upper looper, and disengaging by moving the engaging plate in the opposite direction. An overlock sewing machine that forms an upper looper is proposed. Also with this type of sewing machine, there is a problem that forming the key looper requires a double operation of moving the engagement plate and engaging and disengaging the tip of the engagement plate and the upper looper.

Accordingly, the present invention has been made in order to solve such a conventional drawback, and a key looper can be formed by a simple structure, and a single-needle double-thread overlock sewing and a single-needle three-thread overlock sewing can be performed. It is an object of the present invention to provide an overlock sewing machine capable of easily performing sewing and performing overcasting.

[Means for Solving the Problems] In order to solve such problems, according to the present invention, an edge of a single-needle three-thread performed by an upper looper, a lower looper, and three threads passed through a needle. In an overlock sewing machine capable of switching overlock stitching and edge overlocking of a single needle and two threads performed by using a key looper with a lower looper and two threads passed through a needle, the key looper is a wire spring. When the base end is fixed and cantilevered, it is elastically deformed and when the front end is engaged with the thread hole of the upper looper, it forms a key shape with the upper looper front end portion to catch the lower looper thread, and When the tip is removed from the thread hole of the upper looper, it retreats to a predetermined position where it does not hinder the sewing due to its elasticity. Thread hole It engaged with, and when the 1-needle three thread overedge stitching, to adopt a structure to perform overlock stitch so as to remove the tip of Kagirupa grid consisting hole of the upper looper.

[Operation] According to such a configuration, when performing the overlock stitching of the single needle and two threads, the key looper is elastically deformed so that the tip is engaged with the thread hole of the upper looper, and together with the tip of the upper looper. Form a key shape to catch the lower looper thread,
Also, when performing the overlock stitching of the single needle and three threads, the tip of the key looper is removed from the thread hole of the upper looper, and the key looper is retracted to a predetermined position which does not interfere with the sewing due to the elasticity of the key looper. In this way, it is possible to switch between the overlock stitching of the single needle and the double thread and the overlock stitching of the single needle and the third thread by a simple operation of merely engaging or disengaging the tip of the key looper with the thread hole of the upper looper. Will be possible.

[Embodiment] Hereinafter, the present invention will be described in detail with reference to an embodiment shown in the drawings.

FIG. 1 shows an overlock sewing machine according to an embodiment of the present invention. In FIG. 1, a frame indicated by reference numeral 1 is a frame, and an upper looper swing shaft 2 is provided below the frame 1. Have been. An upper looper swing arm 3 is attached to the upper looper swing shaft 2, and an upper looper attachment shaft 4 is swingably attached to a tip of the upper looper swing arm 3. An upper looper 6 is mounted on the upper part of the upper looper mounting shaft 4 by using a set screw 4a in the direction of the sewing machine needle 5 having a needle thread hole 5a that moves up and down. The upper looper thread hole 6a is formed. The upper looper 6 raises the thread passing through the threaded hole 6a of the upper looper through the swinging motion of the upper looper swinging shaft 3 and the up and down and swinging motions of the upper looper mounting shaft 4 in accordance with the sewing operation as is known. Form a looper.

A lower looper swinging shaft 7 is swingably supported at a lower portion of the frame 1, and a lower looper swinging arm 8 is attached to the lower looper swinging shaft 7, and a lower looper 9 is attached to a tip of the lower looper swinging arm 8. Have been. A thread hole 9 a is formed at the tip of the lower looper 9, and the thread passing therethrough forms a lower looper according to the swinging motion of the lower looper swing arm 8.

A key looper 11 is provided at the upper end of the upper looper mounting shaft 4.
Is attached. The key looper 11 is guided by a key looper guide 12 as shown in FIGS. 2 to 4 and one end is attached to the mounting base 10 via a set screw 13.
The mounting base 10 is mounted on the upper looper mounting shaft 14 by a set screw 14. The key looper 11 is formed of an elastic body (wire spring), and is normally retracted to a predetermined position from the threaded hole 6a of the upper looper due to its elasticity, as shown in FIG. When performing the overlock stitching of the thread, it is held at a position where it does not hinder the sewing operation.

The tip 11a of the key looper 11 can be engaged with the thread hole 6a of the upper looper by hand or the like as shown in FIG.
Overlock stitching of two needles can be performed.

Next, the operation of the overlock sewing machine thus configured will be described.

First, when performing the overlock stitching of the single needle and three threads, the tip 11a of the key looper 11 is separated from the upper looper thread hole 6a as shown in FIG. At this time, the key looper 11 retreats to a predetermined position which does not interfere with sewing which is restricted by the restricting piece of the key looper guide 12 due to its elasticity. Then, thread holes of the sewing machine needle 5, the upper looper 6, and the lower looper 9 are respectively provided.
As is well known, overlocking of a single needle and three threads is performed by operating the sewing machine through the threads 5a, 6a and 9a.

Also, when performing overlock stitching of one needle and two threads,
The thread is pulled out from the thread hole 6a of the upper looper, and as shown in FIG. 3, the key looper 11 is moved rearward and downward with a fingertip to insert the tip 11a of the key looper into the thread hole 6a of the upper looper. The state in which the key looper is inserted into the thread hole 6a of the upper looper in this way is also illustrated in FIG. 5 (a view corresponding to a cross section taken along line AA 'in FIG. 3). Since the key looper has elasticity, it is held in the thread hole 6a of the upper looper by its elastic force,
The upper part of the upper looper is combined with the key looper 11 to form a key shape. If the sewing machine is operated in this state, the needle 5 and the two loops inserted into the thread holes 5a and 9a of the lower looper 9 can perform the overlock stitching of the single needle and the double thread.

In this state, when the sewing machine is switched to the overlock stitching of the single needle and three threads, the key looper 11 is pushed backward against the elastic force with the fingertip so that the tip 11a of the key looper is moved from the upper looper thread hole 6a. The key looper 11 can be returned to the predetermined position shown in FIG. 2 by its elastic force.

Thus, it is possible to switch between the overlock stitching of the single needle and the double thread and the overlock stitching of the single needle and the three thread by operating the fingertip without performing a complicated switching operation.

Further, since the key looper can be easily mounted on the upper looper mounting shaft, even if it is damaged, it can be easily replaced. Further, since the attachment to the upper looper mounting shaft can be adjusted by the screw 14, the engagement or removal of the tip of the key looper with the upper looper thread hole can be adjusted.

FIG. 6 shows another embodiment of a key looper, in which a key looper 11 has a guide groove 12a formed in a guide 12.
Guided through. In this embodiment, the same effects as in the embodiment shown in FIG. 4 can be obtained.

[Effects of the Invention] As described above, according to the overlock sewing machine of the present invention, the key looper is formed by a wire spring, is fixed at the base end, is cantilevered, elastically deforms, and has a distal end formed by the upper looper. When engaged with the thread hole, it becomes a key shape with the tip of the upper looper and catches the lower looper thread.When the tip is removed from the thread hole of the upper looper, it is in a predetermined position that does not interfere with sewing due to its elasticity. When performing the overlock stitching of the single needle and two threads, the tip of the key looper is engaged with the threaded hole of the upper looper, and the overlock stitch of the single needle and three threads is performed. When performing the above, it is possible to switch between the overlock sewing of the single needle and the double thread and the overlock sewing of the single needle and the three threads by a simple operation of simply removing the tip of the key looper from the thread hole of the upper looper. . The key looper can be formed at a low cost with a simple structure made of a wire spring, and the key looper can be supported at a low cost with a simple structure only by fixing the base end. Further, the key looper made of a wire spring is located at an engaging position for engaging with the threaded hole of the upper looper or at a predetermined retracting position which does not hinder sewing, and does not stay halfway between the engaging position and the retracting position. Therefore, the overlock sewing can be reliably switched, and an excellent effect that the key looper does not hinder the sewing can be obtained.

[Brief description of the drawings]

FIG. 1 is a side view showing the structure of the overlock sewing machine according to the present invention, and FIG. 2 (A) is a top view showing the position of a key looper when performing overlock sewing of a single needle and three threads. , FIG. 2 (B) is a side view thereof, and FIG.
Top view showing the position of the key looper when performing the overlock stitching of the two needles, FIG. 3 (B) is a side view thereof, FIG. 4 is an exploded perspective view illustrating attachment of the key looper, FIG. Is a sectional view taken along line AA 'in FIG. 3 (B) showing a state where the key looper and the upper looper are engaged, and FIG. 6 is an exploded perspective view showing another embodiment of the key looper. . 5 ... sewing machine needle 6 ... upper looper 9 ... lower looper 5a, 6a, 9a ... thread hole 11 ... key looper

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-129079 (JP, A) JP-A-54-115948 (JP, A) JP-A-2-172490 (JP, A)

Claims (2)

(57) [Scope of request for utility model registration] 1. An overlocking of a single needle and three threads performed by three threads passed through an upper looper, a lower looper and a needle,
An overlock sewing machine capable of switching overlock sewing of a single needle and two threads performed by a lower looper and two threads passed through a needle using a key looper, wherein the key looper is formed of a wire spring. When the end is fixed and cantilevered and elastically deformed and the tip engages with the threaded hole of the upper looper, it forms a key with the tip of the upper looper to catch the lower looper thread, and the tip ends with the upper looper. When it is removed from the thread hole, it is retracted to a predetermined position where it does not interfere with sewing due to its elasticity. In the case of overlock sewing with one needle and two threads, the tip of the key looper is inserted into the thread hole of the upper looper. An overlock sewing machine wherein the overlock sewing machine is engaged so as to remove the end of the key looper from the thread hole of the upper looper when the overlock sewing is performed with one needle and three threads. 2. The overlock sewing machine according to claim 1, wherein said key looper is detachably mounted on an upper looper mounting shaft.