JPH0763554B2 - Sewing needle for sewing machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing needle used for a sewing machine, and more particularly to a sewing needle for a sewing machine having a long groove formed on one side thereof to communicate with an upper thread insertion hole.

[Prior Art] Generally, a sewing needle used for a sewing machine is provided with a long groove 4 as shown in Figs. 5 and 6 in order to reduce frictional resistance between the upper thread and the cloth when the cloth penetrates. . This long groove 4
Is vertically formed from a lower end of a cylindrical handle 1 to be gripped and fixed to a needle bar of a sewing machine to a needle thread insertion hole 3 provided in a sharp cloth penetrating portion 2 integrally formed with the handle 1. Cage,
The needle thread I1 fed from the filament thread supply source is inserted here. That is, when the sewing needle N penetrates the cloth W and descends, the upper thread located on the supply source side from the upper thread insertion hole 3
As shown in FIG. 3 (a), I1 is introduced into the long groove 4 and drawn with the sewing needle N below the cloth W. Therefore, the upper thread I1 penetrates the cloth W while being covered with one side surface of the sewing needle N, so that the frictional resistance generated between the needle thread I1 and the cloth W is very small.

By reducing the frictional resistance between the upper thread I1 and the cloth W in this manner, the upper thread I1 can be smoothly fed out below the cloth W. Therefore, except in special cases, most sewing needles for sewing machines can be used. The long groove 3 as described above is formed in the. In addition,
In the figure, 4 indicates a needle plate.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional sewing needle for a sewing machine, the long groove 4 is formed from the upper thread insertion hole 3 to the lower end portion of the handle portion 1, and the sewing needle N is at the lowest position. Even when the point is reached,
Since the upper thread I1 and the cloth W are in a non-resistance state, the upper thread loop formation state becomes unstable due to the influence of the upper thread swinging on the cloth and the upper thread loop by the rotary hook. The capture operation of was not performed reliably, and a phenomenon such as skipping occurred.

Further, since the upper thread I1 and the cloth W are in the non-resistance state, even when the sewing needle N reaches the lowermost point, the upper thread I1 is still pulled out to the lower surface of the cloth W, and as shown in FIG. Upper thread on the supply side
There was also a problem that I1 became unnecessarily long, the knot points of the upper and lower threads were pulled out to the lower surface of the cloth, and thread tightening failure occurred. In particular, such a problem remarkably appears when the upper thread I1 is made of chemical fiber and when the high-speed sewing operation is performed.

This invention was made in view of the above-mentioned problems, and the upper thread can be smoothly pulled out under the cloth as in the conventional case, and when the sewing needle reaches the lowermost point, the upper thread is further extra. SUMMARY OF THE INVENTION An object of the present invention is to provide a sewing needle for a sewing machine, which can reliably prevent the needle from being pulled out and the upper thread under the cloth from being influenced by the swing of the upper thread on the cloth, and which can form an appropriate stitch.

[Means for Solving the Problems] In order to solve the above conventional problems, a sewing needle for a sewing machine according to the present invention is provided with a structure described in any one of (a), (b), and (c) below. .

That is, (a) on one side surface of the cloth penetration portion that constitutes the sewing needle, a long groove through which the lower end communicates with the upper thread insertion hole is formed, and the upper end of the long groove is moved to the lowest position of the sewing machine needle bar. It is assumed that the fabric is formed up to the positions that are located within the upper and lower surfaces of the fabric.

(B) On one side surface of the cloth penetrating portion that constitutes the sewing needle, a long groove through which the lower end communicates with the needle thread inserting hole is formed, and the long groove is formed in the cloth penetrating portion of the sewing machine needle bar. It is engraved over the part located in the cloth thickness at the time of the lowest descent, and at least the cloth thickness is at least the depth of the groove in the part of the long groove below the cloth at the time of the descent of the needle bar. It is assumed that the groove located in the inside has a shallow depth.

(C) On one side surface of the cloth penetration portion that constitutes the sewing needle, a long groove through which the lower end communicates with the needle thread insertion hole is formed, and the long groove is formed in the cloth thickness when the sewing machine needle bar is at the lowest position. It is engraved over the part where it is located, and of its long groove,
At least the groove width in the portion located in the cloth thickness when the needle bar is at the lowest position is made narrower than the groove width in the portion located below it.

[Operation] When the sewing operation is performed using the sewing needle for a sewing machine having the configuration described in (a) above, the needle thread is inserted into the long groove formed in the cloth penetration portion in the descending process of the sewing needle. Since it passes through the cloth, it can be smoothly pulled out below the cloth with almost no frictional resistance with the cloth, as in the conventional case.
At the time when the sewing needle reaches the lowest point together with the sewing machine needle bar or immediately before that, the needle thread is pressed and locked to the cloth side by the upper ends of the long grooves located within the upper and lower surfaces of the cloth.
Even if the upper thread sways on the cloth, it is not transmitted to the upper thread located below the cloth, and a stable upper thread loop can always be formed. It is possible to reliably execute the capturing operation of.

Further, since the upper thread is locked when the sewing needle is at the lowest position, the upper thread is not excessively supplied to the lower side of the cloth, good thread tightening can be obtained, and at the proper position. It is possible to form knot points of upper and lower yarns.

In the sewing needle for a sewing machine having the configuration described in (b) above, the needle thread can be smoothly pulled out below the cloth in the descending process of the sewing needle, and when the sewing needle reaches the lowest point. In the above, since the upper thread is pressed against the cloth side and locked by the portion of the long groove where the depth of the groove is shallow, the same effect as (a) can be obtained.

Furthermore, even with the sewing machine sewing needle having the configuration described in (C) above, since the groove width of the long groove located in the cloth thickness is narrow when the sewing needle reaches the lowermost position, this portion The upper thread is not inserted into the long groove but is released to the outside and is pressed against the cloth and locked.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

First, a sewing needle N1 for sewing machine according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

The sewing needle N1 for the sewing machine in this embodiment, as in the conventional case,
The handle portion 11 for fixing to the needle bar of the sewing machine and the sharp cloth penetrating portion 12 integrally formed at the lower end portion thereof are roughly divided into one, and the cloth penetrating portion 12 includes one side surface 12a to the other side surface 12b. A needle thread insertion hole 13 that penetrates to the
4 are formed. The lower end of the long groove 14 communicates with the upper thread insertion hole 13 and is formed above the upper thread insertion hole 13 along the longitudinal direction of the cloth penetration portion 12. The upper end 14a of the long groove 14 has a sewing needle N1 as shown in FIG.
Is formed so as to be positioned at the same height as the upper surface of the cloth W when the point reaches the lowest point. Here, the long groove 14
The bottom portion 14b is gently inclined outward toward the upper end portion 14a.

The sewing needle configured as described above moves up and down integrally with the needle bar of the sewing machine that holds the handle 11, and during the lowering process, the needle thread I1 on the needle thread supply source side fits into the long groove 14. Since it is pulled out below the cloth W while being inserted, almost no frictional resistance is generated between the upper thread I1 and the cloth W, and the upper thread I1 is smoothly drawn below the cloth W. Then, when the sewing needle N reaches the lowermost point, the upper end 14a of the long groove 14 is located at the same height as the upper surface of the cloth W, so that the gap between the sewing needle N1 and the cloth W is extremely narrowed, and the upper thread is placed in this gap. I1 is pinched.

Therefore, even if the upper thread I1 swings in a cloth W shape, the swing is blocked by the sandwiching portion between the upper end portion 14a and the cloth W and is transmitted to the upper thread I1 located below the cloth W. There is no such thing. Therefore, thereafter, the upper thread loop formed by the raising of the sewing needle N1 is stably formed at an appropriate position, and the upper thread loop can be reliably caught by the rotary hook.

Further, as soon as the sewing needle N1 reaches the lowest point, the supply of the thread to the lower side of the cloth is stopped, so that the amount of the upper thread below the cloth does not become longer than necessary, and as shown in FIG. The upper needle thread I1 on the side is maintained in an appropriate amount. Therefore, the thread tightening failure does not occur and the knot point between the upper thread and the lower thread is not pulled out to the lower surface of the cloth, and a good stitch can be formed.

In the above-described embodiment, the upper end 14a of the long groove 14 is formed at a position where it becomes at the same height as the upper surface of the cloth W when the sewing needle N1 reaches the lowest point. Even if the height is set to be the same as the bottom surface of the cloth or the bottom surface of the cloth, the effect similar to that of the above-described embodiment can be expected.

Next, the sewing needle N2 for the sewing machine in the second embodiment of the present invention will be explained based on FIGS. 3 (a) and 3 (b). The same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

The sewing needle N2 in this embodiment is one in which long grooves 24 having different depths are partially formed on one side surface 12a of the cloth penetration portion 12. That is, in this embodiment, the long groove 24 is formed from the upper end (lower end of the handle portion) of the cloth penetration portion 12 to the upper thread insertion hole 13, and the sewing needle N2 of the long groove 24 reaches the lowest point. A part (upper part) located at a height above the upper surface of the cloth W at the time of
The depth H1 of the groove of a is set to be larger than the diameter of the upper thread I1, and the depth H2 of the groove of the portion (lower part) 32b located below the lower thread is smaller than the diameter of the upper thread I1. .

Then, according to the sewing needle N2, when the sewing needle N2 reaches the lowest point, the upper thread I1 is formed on the lower end portion of the upper portion 24a formed by making the groove depth of the long groove 24 shallow and the cloth W. Since the upper thread loop is sandwiched between the upper and the lower thread, it is possible to stabilize the upper thread loop and optimize the length of the upper thread supplied below the cloth.

In this embodiment, the upper portion 24a of the long groove 24 is provided with the sewing needle N.
Although the upper part 24a is formed to extend beyond the upper surface of the cloth W when the cloth W is at the lowest position, the upper portion 24a may be formed above the same position as the lower surface of the cloth W.

Next, a sewing needle N3 in the third embodiment of the present invention will be described with reference to FIGS. In the figure, the same parts as those in the above embodiment are designated by the same reference numerals.

The sewing needle N3 in this embodiment has a long groove 34 formed in the handle portion 12.
Among these, the groove width T1 of the portion (upper portion) 34a located above the upper surface of the cloth W when the sewing needle N3 is at the lowest position is made smaller than the diameter of the needle thread I1, and the needle thread insertion hole 13 is provided from the lower end of this portion 34a. The groove width T2 of the portion (lower portion) 24b communicating with the is smaller than the diameter of the needle thread I1. Here, the groove width T1 is formed so as to become narrower as it goes upward.

Thus, in this sewing needle N3, the upper portion 34 of the long groove 34 is
Since the groove width T2 at a is smaller than the diameter of the upper thread I1, the upper thread I1 is pushed outward from the long groove 34 at the upper portion 34a when the sewing needle N3 reaches the lowest point, and the cloth W Is pressed against and locked. Therefore, also in this embodiment, the same effect as that of the above embodiment can be obtained. Further, the same effect can be expected when the portion of the long groove 34 having a groove width narrower than the diameter of the upper thread (upper portion 34a) is extended to the middle of the cloth thickness or the lower surface of the cloth W.

[Effects of the Invention] As described above, according to the sewing needle for a sewing machine of the present invention, the upper thread can be smoothly supplied to the lower side of the cloth in the descending process of the sewing needle as in the conventional case, and the sewing needle can be used at the maximum. When the lowering point is reached, the upper thread is clamped between the sewing needle and the cloth, so that swing of the upper thread on the cloth can be prevented from being transmitted to the upper thread located below the cloth. As a result, it is possible to maintain an appropriate amount of the upper thread fed below the cloth, and to stabilize the upper thread loop and optimize the stitches.

[Brief description of drawings]

1 is a partially longitudinal side view showing a first embodiment of the present invention,
FIG. 2 is an enlarged vertical side view of an essential part showing a state when the sewing needle shown in FIG. 1 is at the lowest position, FIG. 3 (a) is a front view showing the second embodiment of the present invention, and FIG. ) Is a vertical sectional side view of what is shown in FIG. 4A, FIG. 4A is a plan view showing a third embodiment of the present invention, and FIG. 4B is a vertical section of what is shown in FIG. FIG. 5 is a side view, FIG. 5 is a partially longitudinal side view showing a conventional sewing needle for a sewing machine, and FIGS. 6 (a) and 6 (b) are enlarged views of essential parts showing the usage state of the one shown in FIG. In the figure, 11 …… Handle part 12 …… Cloth penetration part 13 …… Needle thread insertion hole 14 …… Long groove 14a …… Upper end of long groove 23 …… Long groove H1, H2 …… Deep groove 33 …… Long groove T1 , T2 ... Groove width of long groove

Claims (3)

[Claims] 1. A handle portion supported by a needle bar of an ascending / descending sewing machine, a sharp cloth penetrating portion integrally formed with the handle portion, and a needle thread penetrating from one side surface of the cloth penetrating portion to the other side surface. A sewing needle for a sewing machine, comprising: an insertion hole; and a longitudinal groove formed on one side surface of the cloth penetrating portion along a longitudinal direction thereof and having a lower end communicating with the upper thread insertion hole. Is a sewing needle for a sewing machine, wherein an upper end portion thereof is formed up to a position located below the upper and lower surfaces of the cloth when the needle bar is at the lowest position. 2. A handle portion that is supported by a needle bar of a sewing machine that moves up and down, a sharp cloth penetrating portion that is integrally formed with the handle portion, and a needle thread that penetrates from one side surface of the cloth penetrating portion to the other side surface. A sewing needle for a sewing machine, which has an insertion hole and a long groove through which a lower end portion communicates with the upper thread insertion hole and which is formed on one side surface of the cloth penetration portion along the longitudinal direction thereof, wherein the long groove is The cloth penetrating portion is engraved over a portion of the cloth penetrating portion located in the cloth thickness when the needle bar is at the lowest position, and is positioned below the cloth in the long groove when the needle bar is at the lowest position. A sewing needle for a sewing machine, characterized in that the depth of the groove located at least in the cloth thickness is made shallower than the depth of the partial groove. 3. A handle portion supported by a needle bar of an ascending / descending sewing machine, a sharp cloth penetrating portion integrally formed with the handle portion, and a needle thread penetrating from one side surface to the other side surface of the cloth penetrating portion. A sewing needle for a sewing machine having an insertion hole and a long groove formed on one side surface of the cloth penetration portion along a longitudinal direction thereof and having a lower end communicating with the needle thread insertion hole, wherein the long groove is the needle bar. Is engraved over the portion located in the fabric thickness at the lowest descent, and the groove width of at least the portion of the long groove located in the fabric thickness at the lowest descent is located below it. Sewing needle for sewing machines, characterized in that it is smaller than the groove width of the part.