JP2763621B2 - Needle plate of overlock sewing machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an overlock sewing machine, and more particularly, to a structure of a needle plate thereof.

[Prior Art] Generally, an overlock sewing machine draws an elliptical locus so as to intersect with a locus of a needle 2 which moves up and down through a needle plate 1 as shown in FIG. 3 and a lower looper 4 that reciprocates in an arc-shaped trajectory, and the point of the lower looper 4 scoops the needle thread of the needle 2 rising from the lowest point below the needle plate. The upper looper 3 scoops the thread of the lower looper 4 just before reaching the rightmost point, and the needle 2 descending from the top dead center above the needle plate 1 scoops the thread of the upper looper 3 descending from the uppermost point. Overlock sewing is performed. Here, since the upper looper 3 and the lower looper 4 are each configured to be able to draw a locus in a plane substantially perpendicular to the needle plate 1, the needles are inclined in the cloth feeding direction A as shown in FIG. It is configured to move up and down at an angle of about 70 degrees with respect to the needle plate surface, and penetrates the cloth 7 obliquely. Or
The needle 2 is moved up and down almost perpendicularly to the needle plate 1 and the upper looper 3 is moved.
In some cases, the lower looper 4 is configured to move along a locus in a plane inclined about 20 degrees with respect to the needle 2, and the needle 2 penetrates the cloth 7 vertically.

In any case, a needle drop groove 5 is formed in the direction of the cloth feeding direction and a thread slide claw 6 parallel to the needle drop groove is formed so that the sewing thread over the cloth end can easily come out of the needle drop section. (FIG. 6).

[Problems to be Solved by the Invention] In such a conventional needle plate of an overlock sewing machine, the needle drop portion is formed as a groove 5 which is elongated in the cloth feeding direction. Both are pressed into the needle drop groove 5, and in the case of a cloth such as a tricot fabric which is soft and stretchable and has poor needle passage, the cloth 7 falls into the needle drop groove, whereby the needle 2 is bent in the cloth feeding direction. (Figure 7). Further, when the cloth 7 falls into the needle drop groove 5, the end of the cloth moves, so that the cut width becomes unstable or the cloth shifts at the time of stitching. Further, when the needle bends, as shown in FIG. 8, the lower looper 4 which advances the agri 2a of the needle 2 which rises from the lowermost point passes through the lower looper 4 and the positional relationship is not determined when the needle thread is scooped, thereby causing a jump. The lower looper 4 collides with the bent needle 2, causing the needle 2 to be broken or the lower looper blade tip to be damaged. In order to prevent such a collision between the needle 2 and the lower looper 4, a point at which the trajectories of the needle 2 and the lower looper 4 intersect, that is, a point at which the lower looper 4 retreats and the needle 2 descends toward the lowest point; At the time when the needle 2 rises from the lowermost point and the point of the lower looper 4 hooks the needle thread, the needle receiver 8 for correcting the needle position with respect to the lower looper 4 to a normal position is attached to the lower portion of the needle plate. 2 was forcibly guided to the required position.

However, below the needle plate of the overlock sewing machine,
The lower looper drive mechanism, upper looper drive mechanism, cloth feed mechanism, lower knife device and upper and lower looper thread guide device for forming stitches are concentrated, and it is easy to install the front and rear needle receivers in the gap between them. In addition, the needle receiver itself must also have a position adjusting function for guiding the needle to an appropriate position, and there is a problem in that assembly and adjustment are difficult, and the cost of parts increases.

In particular, in a small overlock sewing machine, such a needle receiver must be provided, so that the cost cannot be reduced.

The present invention has been made in order to solve such a conventional problem, and there is provided an overlock sewing machine capable of forming a stable and beautiful seam without a fall of a cloth, preventing generation of a needle bend. It is intended to provide a needle plate.

A further object of the present invention is to provide an inexpensive needle plate for an overlock sewing machine which does not require a needle holder or the like for forcibly stabilizing the needle, and has a small number of components.

Means for Solving the Problems A needle plate of the overlock sewing machine of the present invention that achieves the above object is a needle plate of an overlock sewing machine provided with a needle that moves up and down vertically or inclined with respect to the needle plate. And
It has a cylindrical needle drop hole through which the needle penetrates, and a groove opened between the needle drop hole and the side edge of the needle plate, and the groove faces the side edge with respect to the cloth feeding direction of the needle drop hole. It is opened diagonally forward.

[Function] The groove for removing the sewing thread from the needle drop hole is not provided continuously in the cloth feed direction as in the conventional case, but is opened to the side thereof. It is possible to prevent the cloth from dropping in the feeding direction. By making the width of the groove smaller than the inner diameter of the needle drop hole, the drop of the cloth can be further prevented. By preventing the cloth from dropping, it is possible to prevent the accompanying jumping and bending of the needle.

[Example] Hereinafter, a needle plate of an overlock sewing machine of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the needle plate 10 has an opening 11 into which the cloth feed dog is fitted and a needle drop hole 12 for the needle 20 to penetrate, and cuts the cloth into a concave portion 13a of the side edge 13. Lower knife 30 for (3rd
(Fig.) Is fixed to the sewing machine main body so that it is positioned.

As shown in FIG. 2, the needle 20 moves up and down at an angle of about 20 degrees in front of the cloth feeding direction A, and penetrates the needle plate upper surface 10a at an angle of about 70 degrees.

As shown in FIG. 3, the needle drop hole 12 has an inner diameter slightly larger than the diameter of the needle 20, and a groove 14 is opened diagonally forward from the right toward the side edge 13. This groove 14 is for overlocking stitches formed at the cloth edge formed by the upper and lower looper threads and the needle thread to be discharged from the needle plate. The minimum width required to get out of the needle drop section. Further, the opening on the side edge 13 side of the groove 14 is preferably rounded so that the sewing thread can be easily removed.

In this embodiment, the groove 14 is provided in a straight line obliquely to the right with respect to the cloth feeding direction A, but as shown in FIG.
14 may be cut open to the side of the needle drop hole 12 in the cloth feeding direction, and may be configured to extend in parallel with the cloth feeding direction. In this case, the groove
It is preferable to provide a thread sliding claw 15 between the needle plate 14 and the needle plate side edge 13 for improving thread sliding. In short, the groove 14 need not be opened directly in the cloth feed direction from the needle drop hole 12,
In addition, any shape may be used as long as the thread can easily fall out of the needle drop hole 12.

As shown in FIG. 2, at least the side surface 12a of the needle drop hole 12 on the front side in the cloth feeding direction is inclined in the thickness direction corresponding to the inclination of the needle 20 as shown in FIG. That is, the angle of the inclined surface 12a with respect to the needle plate upper surface 10a is equal to the angle between the needle plate upper surface 10a and the needle 20.

In this case, the distance between the needle and the upper edge 12b of the needle drop hole 12 can be made narrower than in the conventional needle plate, so that the cloth can be prevented from dropping further. The side surface of the groove 14 is also a continuous inclined surface 12a, so that the sewing thread of the stitch can easily fall out of the needle drop hole 12.

As described above, the needle plate of the overlock sewing machine in which the needle is configured to move up and down with respect to the needle plate has been described. However, the present invention relates to an overlock sewing machine in which the needle vertically moves with respect to the needle plate. Needless to say, it can be applied to a needle plate. In this case, the side surfaces of the needle drop hole 12 and the groove 14 are naturally perpendicular to the needle plate.

[Effects of the Invention] As is clear from the above embodiments, according to the needle plate of the overlock sewing machine of the present invention, the needle drop hole is formed in a cylindrical shape, and the needle drop hole is formed on the side edge with respect to the cloth feeding direction. Since the groove for the sewing thread to be pulled out diagonally forward and diagonally forward is opened, it is possible to prevent the cloth from dropping into the opening at the time of needle stick. In particular, it is soft and stretchable, and it can prevent dropping of poorly sewn cloth, eliminating problems associated with it, such as needle bending, eye jumping, unstable cutting width, misalignment of sewing seams, and damage to the blade point. it can. Further, since the opening for removing the needle thread from the needle drop portion and the needle drop portion can be minimized, the above effect can be further enhanced.

Further, according to the needle plate of the overlock sewing machine of the present invention, a needle holder or the like for correcting the position of the needle can be eliminated, so that the number of parts can be reduced and the cost of the overlock sewing machine can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the needle plate of the present invention, FIG. 2 is a diagram showing a relationship between the needle plate and the needle, FIG. 3 is a plan view of a main part of the needle plate of the present invention, FIG. Fig. 5 is a view showing another embodiment of the needle plate of the present invention. Fig. 5 is a view showing the movement of the needle and the upper and lower loopers of the overlock sewing machine. Fig. 6 is a view showing the conventional needle plate.
FIG. 8 and FIG. 8 are diagrams showing the state of falling of the cloth and bending of the needle in the conventional needle plate, respectively. 10 Needle plate 12 Needle drop hole 12a Slope 13 Needle plate side edge 14 Groove 20 Needle A Feed direction

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Claims (1)

(57) [Claims] 1. A needle plate of an overlock sewing machine provided with a needle (20) that moves vertically or obliquely with respect to a needle plate (10), wherein the needle needle hole (20) penetrates the needle. 12)
And a groove (14) opened between the needle drop hole and the needle plate side edge (13), wherein the groove is formed on the side edge with respect to the cloth feeding direction (A) of the needle drop hole. A needle plate of an overlock sewing machine, characterized in that the needle plate is opened diagonally forward toward.