JPH0135740Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Field of Application This invention relates to an overlock sewing machine that stitches the edges of cloth by operating a needle, an upper looper, and a lower looper in an interlocking manner.

Conventional technology Overlock sewing machines pass thread through upper and lower loopers, which are separate from the sewing machine's needle.
There are two types of stitching: one is to stitch three threads on one needle, and the other is to stitch two threads per needle, in which the thread is passed only through the lower looper.
Utility Model Publication No. 57-15386, Publication No. 60-18771,
As described in Publication No. 60-18772, etc., the base of a hook along the upper looper is pivotally attached to the upper looper holder, and when using three threads per needle, this hook is attached. The retaining piece is kept in a non-operating position, and when using two threads per needle, the retaining piece is brought into contact with and along the upper looper, and the lower looper forms the thread hooking part formed at the tip of the retaining piece. Some are designed to be engaged with loop threads. In addition, one upper looper has a threading hole for three threads per needle and two
In the mounting hole of the upper looper holder, which forms a thread hooking part for the main thread, and into which the mounting shaft of the upper looper fits.
There is a device in which one upper looper can be used for both three threads per needle and two threads per needle by rotating it by 90 degrees (Japanese Utility Model Publication No. 18077/1983).

Problems that the invention aims to solve Compared to the former, the latter conventional method has the advantage that it has fewer parts and can perform switching operations more reliably. Since the upper looper for 3 needle threads and the upper looper for 1 needle 2 threads are integrally formed, no matter which way you switch, there will be some overhang on the sides, which may cause the threads to intersect with the lower looper or loop threads. This has resulted in a drawback that it is difficult to engage smoothly. For this reason, it has become desirable to improve the upper looper so that it can be used in common, and no matter which way the upper looper is switched, the crossing with the lower looper and the engagement with the loop yarn are always performed smoothly.

Means for Solving the Problems Therefore, the present invention provides an overlock sewing machine in which a needle, an upper looper, and a lower looper are operated in an intersecting manner to hem the edge of a cloth. They are formed into a forked shape with a phase difference of 180° in the vertical direction from each other across the axis,
One upper looper piece is formed with a threading part for two threads per needle, and the other upper looper piece is formed with a threading hole for three threads per needle, and the mounting shaft of this upper looper is attached to the upper looper holder. This invention provides an overlock sewing machine characterized in that the sewing machine is mounted so as to be able to rotate through 180 degrees within a mounting hole formed in the sewing machine.

Function As described above, the present invention forms the upper looper in a bifurcated shape with a phase difference of 180° in the vertical direction across the axis of the upper looper, and one side is used as the upper looper for use with two threads per needle. One looper piece is formed, and the other is formed as an upper looper piece for one needle and three threads, so that one upper looper can be shared, so no matter which one is used, the other upper looper piece protrudes to the side. Since it is located directly above the upper looper piece that is in use, operations such as interlacing and engagement with the lower looper and the loop yarn are performed smoothly.

Embodiments Examples of the present invention will be described below with reference to the drawings.

In the figure, 1 is a sewing machine needle, 2 is an upper looper, and 3 is a lower looper.

As shown in FIG. 1, the upper looper 2 is formed into a bifurcated shape with a phase difference of 180° in the vertical direction from each other across the axis L of the upper looper 2. A threading part 4 for two needle threads is provided, a threading hole 5 for one needle and three threads is provided in the other upper looper piece b, a knob 6 for rotating operation is provided at the base, and both upper looper pieces A mounting shaft 7 common to both a and b is inserted into a mounting hole 9 provided in the upper looper holder 8, and fixed at a predetermined angle and position by a set screw 10. Note that the upper looper 2
In the state shown in the figure, the upper looper piece b for one needle and three threads is in the use position. In this state of use, the other upper looper piece a is located directly above it as shown in Fig. 2 (in the direction of the arrow in Fig. 1), and by aligning their axes in the vertical direction, the upper looper piece a protrudes laterally. The looper 3 is kept to a minimum so that the intersection with the lower looper 3 can be smoothly performed.

The fitting between the mounting shaft 7 of the upper looper 2 and the mounting hole 9 of the upper looper holder 8 is achieved by fitting the mounting shaft 7 of the upper looper 2 with the mounting hole 9 of the upper looper holder 8, as shown in FIGS.
A ball 13, which is pressed by a coil spring 12, is elastically fitted into the recess 11 from the side surface of the upper looper holder 8. As shown in the figure, a fan-shaped groove 14 with a V-shaped cross section is formed on the mounting shaft 7, and the inner end of the set screw 10 screwed into the side surface of the upper looper holder 8 is brought into contact with the end of the groove 14. By loosening the set screw 10 and rotating the upper looper 2 by 180 degrees in the vertical direction within the mounting hole 9,
It is configured such that the positions of the upper and lower looper pieces a and b can be switched to switch their use. Note that 15 is the upper looper shaft, and 16 is its bearing.

Effects of the invention As mentioned above, in the present invention, one upper looper is formed into a forked shape in the vertical direction, a thread hooking part for two threads per needle is formed on one upper looper piece, and the other A threading hole for three threads per needle was formed in the upper looper piece, and the upper looper mounting shaft was installed so that it could rotate 180° within the mounting hole formed in the upper looper holder. When the upper looper piece is placed in use, the other upper looper piece is placed directly above it to avoid interference with the lower looper, etc., and is placed on the side of the axis of the upper looper. Eliminates protruding parts and allows smooth oversewing at all times. Further, since each upper looper piece is formed into a forked shape, there is a practical effect that each piece can be made thick enough to have sufficient strength and rigidity.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway elevational view showing an embodiment of the present invention, Fig. 2 is a plan view of the upper looper along the arrow direction in Fig. 1, and Fig. 3 is a line A-A' in Fig. 1. 4 is a sectional view taken along line B-B' of FIG. 1; FIG. 1... Needle, 2... Upper looper, 3... Lower looper, L... Axis line, a... One upper looper piece, 4
...Thread hook part, b...Other upper looper piece, 5...
Threading hole, 7...Mounting shaft, 8...Upper looper holder, 9...Mounting hole, 10...Set screw, 11...
... recess, 12 ... coil spring, 13 ... ball,
14...Groove, 15...Upper looper shaft, 16...Bearing.

Claims (1)

[Scope of utility model registration request] In an overlock sewing machine in which a needle 1, an upper looper 2, and a lower looper 3 are operated in an intersecting manner to stitch the edges of cloth, the upper looper 2 is operated perpendicularly to each other across the axis L of the upper looper.
It is formed into a bifurcated shape with a phase difference of 180°, and one upper looper piece a has a thread hooking part 4 for two threads per needle, and the other upper looper piece b has a thread hooking part 4 for three threads per needle. The mounting shaft 7 of the upper looper 2 is inserted into the mounting hole 9 formed in the upper looper holder 8.
An overlock sewing machine that is equipped with a 180° rotation.