JPH03224592A - Sewing needle for sewing machine - Google Patents

Abstract

PURPOSE:To prevent a fact that the needle thread is drawn out excessively and the needle thread under cloth is influenced by oscillation of the needle thread on cloth by forming a long groove in which the needle thread can be inserted through on one side face of a cloth- through part of a sewing needle up to the part in which its upper end part is positioned in both the upper and the lower faces of cloth at the time of the most descent of a sewing machine needle bar. CONSTITUTION:In a cloth-through part 12 of a sewing machine sewing needle N1, an needle thread insert-through hole 13 which passes through from its one side part 12a to the other side face 12b is formed, and on one side face 12a, a long groove 14 is formed. This long groove 14 is formed so that its lower end part communicates with the needle thread insert- through hole 13, and also, formed along the longitudinal direction of the cloth-through part 12 to the upper part of the needle thread insert-through hole 13, and the upper end part 14a of the long groove 14 is formed so that it is positioned at the same height as the upper face of cloth W at the point of time when the sewing needle N1 reaches the most descent point. Accordingly, at the point of time when the sewing needle N1 reaches the most descent point together with a sewing machine needle bar or immediately before it, the needle thread is held down to the cloth side by the upper end part 14a of the long groove 14 positioned in both the upper and the lower faces of the cloth W and stopped. In such a way, even if the needle thread is oscillated on the cloth W, it is not transferred to the needle thread positioned in the lower part of the cloth W.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a sewing needle for use in a sewing machine, and more particularly to a sewing needle for a sewing machine that has a long groove formed on its lower side surface to communicate with an upper thread insertion hole.

[Prior Art] In general, a sewing needle used in a sewing machine is formed with a long groove 4 as shown in FIGS. 5 and 6 in order to reduce the frictional resistance between the upper thread and the cloth when penetrating the cloth. . This long groove 4
is formed vertically extending from the lower end of the cylindrical handle l to be gripped and fixed to the needle bar of the sewing machine to the needle thread insertion hole 3 provided in the sharp cloth penetration part 2 formed integrally therewith. Ori,
The upper thread II paid out from the upper thread supply source is inserted through this hole. That is, when the sewing needle N passes through the fabric W and descends, the upper thread It located on the supply source side from the upper thread insertion hole 3 is introduced into the long groove 4 as shown in FIG. At the same time, the cloth W is pulled downward. For this reason, the needle thread 11 does not cover one side of the sewing needle N, but instead passes through the cloth W, and the frictional resistance generated between it and the cloth W becomes minimal.

In this way, by reducing the frictional resistance between the needle thread 11 and the cloth W, the needle thread It can be smoothly fed out downward from the cloth W (7), so that most sewing machines, except in special cases, The sewing needle is formed with the long groove 3 as described above. In Figure 1, numeral 4 indicates the throat plate.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional sewing needle for sewing machines, the long groove 4 is formed from the upper thread insertion hole 3 to the lower end of the handle 1, and the &I needle N. Even when the lowermost point has been reached, the upper thread 11 and the cloth W are in a state of no resistance, so
The formation state of the needle thread loop became unstable due to the influence of the swinging of the needle thread on the fabric, and the rotating shuttle did not reliably capture the needle thread loop, resulting in phenomena such as skipped stitches.

In addition, since the needle thread 11 and the cloth W are in a non-resistance state, even if the sewing needle N reaches its lowest point, the needle thread l or the cloth W
As shown in Fig. 6, the upper thread If on the supply source side becomes longer than necessary, and the knot points of both the upper and lower threads are pulled out to the lower surface of the fabric, or thread alignment defects occur. There was also the problem. Particularly, such a problem appears conspicuously when the upper thread If is made of chemical fiber and when high-speed sewing operation is performed.

This invention was made by focusing on the above-mentioned problem, and it is possible to smoothly pull out the needle thread under the fabric as before, and when the sewing needle reaches the lowest point, it is not necessary to pull it up any further. To provide a sewing needle for a sewing machine which can reliably prevent a thread from being pulled out or be influenced by the swinging of the upper thread under the cloth or on the cloth, and can form a proper seam.

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

That is, (a) a long groove through which the upper thread can be inserted is formed on one side of the fabric penetrating part constituting the sewing needle, and the lower end communicates with the upper thread insertion hole, and the upper end of the long groove is connected to the lowermost part of the sewing machine needle bar. At the same time, it is assumed that it is formed up to a point located within both the upper and lower surfaces of the cloth.

(b) A long groove through which the upper thread can be inserted is formed on one side of the cloth penetrating part of the sewing needle, and the lower end communicates with the upper thread insertion hole. The long groove is carved over the part of the fabric that is located in the thickness when the needle bar is lowered to its lowest position, and the depth of the long groove is at least in the lower part of the fabric when the needle bar is lowered to its lowest position. The depth of the groove in the portion located at is made shallow.

(c) A long groove through which the upper thread can be inserted is formed on one side of the fabric penetrating part constituting the N needle, and the lower end communicates with the upper thread insertion hole. It is engraved over the part where it is located, and among the long grooves,
At least the groove width in the portion located in the inventory when the needle bar is at its lowest position is made narrower than the groove width in the portion located below it.

[Function] When sewing is performed using a sewing needle for a sewing machine having the configuration described in (a) above, the upper thread is inserted into the long groove formed in the fabric penetrating portion during the descending process of the sewing needle. Because it passes through the cloth, it is pulled out smoothly below the cloth without creating any frictional resistance with the cloth, as in the past.
At or just before the sewing needle reaches its lowest point together with the sewing machine needle bar, the upper thread is pressed against the fabric by the upper end of the long groove located on both the upper and lower sides of the fabric.
Even if the needle thread oscillates on the fabric, it will not be transmitted to the needle thread located below the fabric, and a stable needle thread loop can be formed at all times. The capture operation can be executed reliably.

In addition, by locking the upper thread when the sewing needle is lowered to its lowest point, the upper thread is not fed downward into the fabric, making it possible to obtain a good thread alignment and to ensure proper positioning. It is possible to form a knot point for both the upper and lower threads.

In addition, even with the sewing machine needle having the configuration described in (b) above, during the descending process of the sewing needle, the upper thread can be smoothly pulled out below the fabric, and when the sewing needle reaches the lowest point, In this case, the same effect as in (a) can be obtained because the needle thread is pressed and locked against the fabric side by the shallow part of the long groove.

Furthermore, even with the sewing machine needle having the configuration described in (c) above, the groove width of the long groove located in the inventory is narrow when the sewing needle reaches the lowest position, so the width of the long groove in this part is narrow. The needle thread is not inserted into the long groove but comes out to the outside, comes into pressure contact with the cloth, and is locked.

[Embodiments of the Invention] Examples of the present invention will be described below with reference to FIGS. 1 to 4.

First, a sewing needle Nl for a sewing machine according to a first embodiment of the present invention will be explained based on FIGS. 1 and 2.

As with the conventional sewing machine needle Nl in this embodiment, it is roughly divided into a handle part 11 for fixing to the needle bar of the sewing machine, and a sharp cloth penetrating part 12 integrally formed at its lower end. The cloth penetrating portion 12 has a side surface 12a to the other side surface 12a.
An upper thread insertion hole 13 penetrating through the b is formed, and the -
A long groove 14 is formed in the side surface 12a. This long groove 1
4 communicates with the needle thread insertion hole 13 at its lower end, and is formed above the needle thread insertion hole 13 along the longitudinal direction of the fabric penetrating portion 12. The upper end portion 14 of the long groove 14
As shown in FIG. 2, a is formed to be located at the same height as the upper surface of the cloth W when the sewing needle Nl reaches its lowest point. In this case, the bottom portion 14b of the long groove 14 extends to the upper end portion 14a and is gently inclined outward.

The sewing needle configured as described above moves up and down in unison with the needle bar of the sewing machine that grips the handle 11, but during the descending process, the needle thread 11 on the needle thread supply source side is inside the long groove 14. Since the needle thread II is pulled out below the cloth W while being inserted into the thread IaW, almost no frictional resistance is generated between the needle thread II and IaW, and the needle thread II is smoothly pulled out below the fabric W. and,
When the sewing needle N reaches the lowest point, the upper end 14a of the long groove 14
Since the sewing needle Nl is located at the same height as the upper surface of the cloth W, the gap between the sewing needle Nl and the cloth W is extremely narrow, and the needle thread II is held in this gap.

For this reason, even if the needle thread 11 swings in the shape of the cloth W,
The swinging motion is blocked by the sandwiching portion between the upper end portion 14a and the cloth W, and is not transmitted to the needle thread If located below the cloth W. Therefore, after that, the needle thread loop formed by raising the sewing needle Nl is stably formed at an appropriate position, and the needle thread loop can be reliably captured by the rotary shuttle.

In addition, as soon as the 1M needle Nl reaches its lowest point, the supply of thread to the lower part of the fabric stops, so the amount of upper thread at the lower part of the fabric does not become longer than necessary, and the supply source The side needle thread It is maintained at an appropriate amount. For this reason, it is possible to form a good seam without causing thread alignment defects or having the node between the upper thread and the bobbin thread pulled out to the bottom surface of the cloth.

3. In the above embodiment, the long groove 1 is located at the same height as the upper surface of the cloth W when the sewing needle Nl reaches its lowest point.
4, the upper end 14a of the long groove 14 is formed.
Even if a is set to a height that is submerged in the inventory or a height that is the same as the lower surface of the cloth, substantially the same effect as in the above embodiment can be expected.

Next, a sewing needle N2 for a sewing machine according to a second embodiment of the present invention will be explained based on FIGS. 3(a) and 3(b). Note that the same parts as in the first embodiment are given the same reference numerals, and detailed explanation thereof will be omitted.

The sewing needle N2 in this embodiment is one side 1 of the cloth penetrating portion 12.
Long grooves 24 having different depths are formed in portions 2a. That is, in this embodiment, the long groove 24 is formed from the upper end of the cloth penetrating portion 12 (lower end of the handle) to the needle thread insertion hole 13, and the long groove 24 is formed in the long groove 24 when the sewing needle N2 reaches its lowest point. At this point, the depth Hl of the groove in the part (upper part) 24a located at a height higher than the upper surface of the cloth W is set to be larger than the diameter of the upper thread If, and the depth Hl of the groove in the part (lower part) 32b located below it The depth H2 of the groove is smaller than the diameter of the upper thread 11.

According to this sewing needle N2, when the sewing needle N2 reaches the lowest point, the needle thread 11 is moved between the lower end portion of the upper portion 24a of the long groove 24 formed with a shallower groove depth and the cloth W. Since it is held between the upper and lower ends of the cloth, it is possible to stabilize the looseness of the upper thread and to optimize the amount of upper thread supplied to the lower part of the fabric.

In this embodiment, the upper part 24a of the long groove 24 is formed so as to extend beyond the upper surface of the cloth W when the sewing needle N is lowered to its lowest position, or the upper part 24a is formed to extend beyond the position where it is the same as the lower surface of the cloth W. It may be formed into

Next, a sewing needle N3 according to a third embodiment of the present invention will be explained with reference to FIGS. 4(a) and 4(b). In the figure, the same parts as in the above embodiment are given the same reference numerals.

In this embodiment, the sewing needle N3 has a groove width Tl of a portion (upper portion) of the long groove 34 formed in the handle 12, which is located above the upper surface of the cloth W when the sewing needle N3 is lowered to the lowest level, by the needle thread ■1. The groove width T of the portion (lower portion) 24b that communicates with the upper thread insertion hole 13 from the lower end of this portion 34a
2 is made smaller than the diameter of the upper thread II. In addition,
Here, the groove width Tl is formed to become narrower as it goes upward.

In this way, in this sewing needle N3, since the groove width T2 at the upper part 34a of the long groove 34 is narrower than the diameter of the needle thread II, when the sewing needle N3 reaches the lowest point,
The upper thread II is pushed outward from the long groove 34 in the upper part 34a, is pressed against the cloth W, and is locked. Therefore, in this embodiment as well, the same effects as in the above embodiment can be obtained. Moreover, substantially the same effect can be expected even if the part (upper part 34a) of the long groove 34 having a groove width narrower than the diameter of the needle thread is kept in stock or extended to the lower surface of the cloth W.

[Effects of the Invention] As explained above, according to the sewing needle for a sewing machine according to the present invention, the needle thread can be smoothly fed downward into the cloth in the lowering process of the sewing needle, as in the conventional case, and moreover, the sewing needle Since the needle thread is held between the sewing needle and the fabric when it reaches the lowering point, it is possible to prevent vibrations of the needle thread on the fabric from being transmitted to the needle thread located below the fabric. In this way, it is possible to maintain an appropriate amount of the needle thread that is let out downward from the fabric, thereby making it possible to stabilize the needle thread loop and optimize the stitching.

[Brief explanation of drawings]

FIG. 1 is a partially longitudinal side view showing a first embodiment of the invention;
2 is an enlarged vertical sectional side view of the main part showing the state of the sewing needle shown in FIG. 1 when it is at its lowest point; FIG. ) is a longitudinal sectional side view of the thing shown in FIG. 4(a), FIG. 4(a) is a plan view showing the third embodiment of the present invention, and 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 of the sewing needle shown in FIG. 5, showing the state in which it is used. In the figure, 1...Handle part 2...Fabric penetration part 3...Needle thread insertion hole 4...Long groove 4a...Long groove upper end 23 ...Long groove Hl, H2-...Long groove depth 33...Long groove TI, T2...Long groove groove width

Claims (3)

[Claims] (1) A handle supported by a needle bar of a sewing machine that moves up and down, a sharp cloth penetrating part integrally formed on the handle, and an upper thread insertion hole passing through from one side of the cloth penetrating part to the other side. and a long groove formed along the longitudinal direction of the cloth penetrating part, the long groove having a lower end communicating with the needle thread insertion hole and allowing the upper thread to pass therethrough, the long groove comprising: A sewing needle for a sewing machine, characterized in that an upper end portion thereof extends to a position below both the upper and lower surfaces of the cloth when the needle bar is lowered to its lowest position. (2) A handle supported by a needle bar of a sewing machine that moves up and down; a sharp cloth penetrating part integrally formed in the handle; and an upper thread insertion hole penetrating from one side of the cloth penetrating part to the other side; In a sewing needle for a sewing machine, the sewing needle has a long groove carved along the longitudinal direction on one side of the cloth penetrating portion, the lower end of which communicates with the needle thread insertion hole and into which the upper thread can be passed, Among the long grooves, the grooves are carved over the part of the fabric that is located in the thickness when the needle bar is lowered to its lowest position, and among the long grooves, the groove is located below the fabric when the needle bar is lowered to its lowest position. A sewing needle for a sewing machine, characterized in that the depth of the groove is shallower at least in a portion located in the thickness of the fabric. (3) A handle supported by the needle bar of the sewing machine that moves up and down, a sharp cloth penetrating part integrally formed in the handle, and an upper thread insertion hole penetrating from one side of the cloth penetrating part to the other side. and a long groove formed on one side of the fabric penetrating portion along its longitudinal direction, the long groove having a lower end communicating with the upper thread insertion hole, the long groove being located at the top of the needle bar. It is carved over the part of the material that is located in the thickness of the material when the needle bar is lowered, and the groove width of the part of the long groove that is located in the material thickness when the needle bar is lowered is the same as that of the part that is located below the long groove. A sewing needle for a sewing machine characterized by being narrower than the groove width.