JP6843326B2 - Sewing needles, sewing needle manufacturing methods and sewing methods - Google Patents

Description

The present invention relates to a sewing needle characterized by a tip shape.

In some cases, the sewing needle is inserted diagonally with respect to the object to be sewn and sewn. For example, as described in Patent Document 1 (particularly, the third embodiment and the fourth embodiment), when the tatami mat is reverse-sewn using a straight sewing needle, the sewing needle is slanted with respect to the tatami mat to be sewn. Will enter.

Japanese Patent No. 3369476

By the way, in the tatami mat sewing as described above, it is necessary to sew a sewing needle through a stack of several interior materials called boards covered with a tatami mat surface. Therefore, the sewing needle needs to easily penetrate the sewing object and easily bite into the sewing object.

However, when a straight needle is used for the sewing needle, the needle tip may not bite the sewing object and the needle tip may slip on the surface of the sewing object (so-called needle flow occurs).

Therefore, an object of the present invention is to provide a sewing needle in which needle flow is unlikely to occur even when the sewing needle is slanted with respect to the object to be sewn and sewn.

The present invention has been made to solve the above-mentioned problems, and is characterized by the following.

The invention according to claim 1 is a sewing needle used by being attached to a sewing machine, which is provided with a needle tip having a shape in which the tip of a cone is cut off at an acute angle, and the needle tip is flat and inclined with respect to the center line of the cone. A surface is formed so that the acute angle angle formed by the center line of the cone and the flat surface is larger than the acute angle angle formed by the center line of the cone and the tapered surface of the cone. It is characterized in that it is formed in.

The invention according to claim 2 is characterized in that, in addition to the feature points of the invention according to claim 1, the tip of the sewing needle is located at an eccentric position with respect to the center line of the cone.

According to the third aspect of the present invention, in a sewing needle attached to a sewing machine and used, a flat surface inclined with respect to the center line of the cone is formed by cutting the tip of the sewing needle formed in a conical shape at an acute angle. The acute angle formed by the center line of the cone and the flat surface is larger than the angle of the acute angle formed by the center line of the cone and the tapered surface of the cone. It is characterized by that.

The present invention is as described above, and the sewing needle is provided with a needle tip having a shape in which the tip of the cone is cut off at an angle, and a flat surface inclined with respect to the center line of the cone is formed on the needle tip. By using such a sewing needle, it is possible to make it easier for the needle tip to bite into the sewing object by utilizing the flat surface.

Further, since this sewing needle can be manufactured only by diagonally cutting the tip of the needle manufactured in a normal manufacturing process, it is easy to process and can be manufactured at low cost.

If the flat surface is angled too much with respect to the taper angle of the cone, the bite is improved, but there is a problem that the penetration performance is lowered and the needle hole mark is increased. Therefore, it is necessary to set the angle and size of the flat surface in consideration of conditions such as the angle and hardness of the object to be sewn. In this respect, according to the sewing needle of the present invention, since sewing needles having various settings can be easily manufactured, the angle and size of the flat surface can be easily adjusted. Therefore, it is possible to easily manufacture a sewing needle that prevents needle flow, maintains penetrating force, and makes needle hole marks inconspicuous.

It is an enlarged view of the needle tip of a sewing needle, and is (a) a front view, (b) a plan view, and (c) a side view. It is the schematic when the sewing needle was used for tatami mat sewing. It is a figure which shows (a) the relationship between a sewing needle and a sewing object, and (b) is a figure which shows the relationship between a non-eccentric sewing needle and a sewing object. It is a figure for demonstrating the dimension of a sewing needle and the like.

An embodiment of the present invention will be described with reference to the drawings.

The sewing needle 10 according to the present embodiment is formed straight and is suitable for sewing such that the needle is inserted obliquely with respect to the sewing object 20, and is used by being reciprocated by the sewing machine 30. As shown in FIG. 1, the sewing needle 10 includes a rod-shaped needle trunk portion 13 to be inserted into the sewing object 20, and a needle tip portion 14 formed on the tip end side of the needle trunk portion 13. Although not shown in particular, a handle portion is provided on the anti-tip side of the needle trunk portion 13, and by attaching this handle portion to the needle support portion 31 of the sewing machine 30, the sewing needle 10 is fixed to the sewing machine 30 for use. (See Fig. 2). Further, the needle trunk portion 13 is formed with a needle hole for passing a thread used for sewing and a thread groove for guiding the thread into the needle hole.

As shown in FIG. 1, the needle tip portion 14 of the sewing needle 10 has a shape in which the tip of a cone is cut off diagonally. Specifically, as shown in FIG. 4, when the center line X of the sewing needle 10 connecting the cross-sectional centers of the needle trunk 13 is assumed, the conical portion 15 which is a part of the conical shape having an apex on the center line X is assumed. And a flat surface 16 formed when the apex portion of the conical portion 15 is cut by a predetermined plane are formed on the needle tip portion 14. In the present embodiment, the conical portion 15 is a part of the perfect conical shape, but the conical shape forming the conical portion 15 does not have to be a perfect conical shape. The conical portion 15 may have a conical shape that is tapered, for example, may have a cannonball shape, or the cross section corresponding to the bottom surface may have an elliptical shape.

Since the flat surface 16 is inclined with respect to the center line X of the sewing needle 10, the flat surface 16 is tapered in the tip direction, and the most tip side is the needle tip 11 of the sewing needle 10. As shown in FIG. 4, the needle tip 11 is formed at a position eccentric with respect to the center line X of the sewing needle 10. By eccentricity of the needle tip 11 of the sewing needle 10 with respect to the center line X of the sewing needle 10 in this way, the side closest to the needle tip 11 (left side in FIG. 4) and the side farthest from the needle tip 11 (right side in FIG. 4). ) And the needle tip 11 are formed so that the inclination angles toward the needle tip 11 are different.

Specifically, on the side closest to the needle tip 11, the tapered surface of the conical portion 15 extends to the needle tip 11, so that the tapered surface determines the inclination angle toward the needle tip 11. This inclination angle is defined as an angle A formed by the center line X and the tapered surface of the conical portion 15. Further, since the flat surface 16 is provided on the side farthest from the needle tip 11, the inclination angle toward the needle tip 11 is determined by the flat surface 16. This inclination angle is defined as an angle B formed by the center line X and the flat surface 16. At this time, it is formed so that the relationship of angle A <angle B holds.

As will be described in detail later, if the angle B is increased, needle slippage is less likely to occur, but the needle hole mark becomes larger and it becomes difficult to penetrate the sewing object 20. Therefore, the angle B needs to be an appropriate value that balances the improvement of the needle slip, the reduction of the needle hole trace, and the securing of the penetrating force. The value of the well-balanced angle B varies depending on the thickness of the sewing object 20 and the sewing needle 10, but it is desirable that the angle B is in the range of 25 to 50 degrees. Further, in comparison with the angle A, it is desirable that the angle B is in the range of 2 to 20 times the angle A. Further, in order to obtain a sufficient penetrating force, the angle (value of angle A + angle B) of the needle tip 11 of the sewing needle 10 is preferably in the range of 20 to 60 degrees, and is in the range of 30 to 45 degrees. Is even more desirable.

Further, considering the damage to the sewing object 20, the length of the flat surface 16 when viewed in the center line X direction is also important. This is because if the length of the flat surface 16 is increased, needle slippage is less likely to occur, but the needle hole mark becomes large. Here, as shown in FIG. 4, assuming that the length of the flat surface 16 when viewed in the center line X direction is L1 and the length of the conical portion 15 when viewed in the center line X direction is L2, L1 ≦ The relationship of L2 is established. The value of L1 is preferably 50% or less of L2, and more preferably 20 to 40% of L2.

When manufacturing the sewing needle 10, first, a needle whose tip is not eccentric is prepared by a known method. That is, a needle is created such that the tip of the conical portion 15 is the tip of the sewing needle 10. Then, by cutting the tip of the conical portion 15 diagonally, a flat surface 16 inclined with respect to the center line X of the sewing needle 10 is formed on the needle tip portion 14.

In this embodiment, the flat surface 16 is plated (for example, electroless Ni plating). By plating the cutting surface in this way, it is difficult for an object to adhere to the needle tip portion 14. Therefore, for example, when the sewing needle 10 is used for tatami mat sewing, it is possible to prevent the components of the board from adhering to the sewing needle 10 when the board formed by solidifying the wooden powder is penetrated.

FIG. 2 is a diagram illustrating a sewing method using the sewing needle 10. As shown in FIG. 2, the sewing needle 10 is attached to the needle support portion 31 of the sewing machine 30 and used. The sewing machine 30 includes a drive unit 32 for reciprocating the needle support portion 31 on which the sewing needle 10 is mounted. When the drive unit 32 operates, the sewing needle 10 reciprocates, whereby the sewing object 20 is sewn. At this time, the sewing object 20 is diagonally fixed to the sewing machine 30. In FIG. 2, the tatami mat, which is the object to be sewn 20, is fixed obliquely to the sewing machine 30, and the edge of the tatami mat is arranged so as to face the needle tip 11 of the sewing needle 10. When the sewing machine 30 is operated in such a state, the sewing needle 10 enters the sewing object 20 at an angle as shown in FIG. 3A. At this time, the sewing needle 10 is attached so that the flat surface 16 faces the side (right side in FIG. 3A) where the surface 21 of the sewing object 20 and the center line X of the sewing needle 10 form an obtuse angle. By arranging and using the sewing needle 10 in this way, the needle flow can be effectively prevented.

That is, when the conventional sewing needle 10'is used as shown in FIG. 3B, the maximum angle θ2 formed by the needle tip portion 14'and the surface 21 of the sewing object 20 is close to an obtuse angle. The force pushing 10'was easy to work in the horizontal direction with respect to the surface 21 of the sewing object 20. By applying such a force, the sewing needle 10'becomes slippery on the surface 21 of the sewing object 20. Further, when such a conventional sewing needle 10'is used for tatami sewing, it is necessary to penetrate the stacked boards, so that the sewing needle 10'needs to be bitten on the board many times. At this time, since the tension of the needle thread increases each time the needle penetrates the board, the sewing needle 10'bends and the needle slips easily.

The sewing needle 10 according to the present embodiment is for solving such a problem of the conventional sewing needle 10'and effectively preventing needle slippage. That is, as shown in FIG. 3A, since the flat surface 16 is provided, the angle θ1 formed by the flat surface 16 and the surface 21 of the sewing object 20 is close to a right angle, and the sewing needle 10 is pushed. The force tends to act in the direction perpendicular to the surface 21 of the sewing object 20. Further, when the flat surface 16 hits the surface 21 of the sewing object 20, the surface hits the sewing object 20 and the friction becomes large. Therefore, the sewing needle 10 easily bites into the surface 21 of the sewing object 20, and the sewing needle 10 penetrates the sewing object 20 without slipping on the surface 21 of the sewing object 20.

By the way, although there have been needles with an eccentric tip, it has been difficult to process the tip. Therefore, there are problems that the manufacturing cost is high and that it is not possible to easily manufacture a needle having the optimum setting for each sewing object 20. In this respect, according to the present embodiment, it is possible to easily change what kind of flat surface 16 is formed by cutting. Therefore, the sewing needle 10 suitable for the usage environment can be easily obtained in consideration of the approach angle of the needle, the hardness of the sewing object 20, the allowable range of the needle hole mark, and the like.

In the above-described embodiment, an example in which the sewing needle 10 is used for tatami mat sewing has been described, but the embodiment of the present invention is not limited to this. For example, the sewing needle 10 of the present invention can be used for sewing using an overlock sewing machine, a sewing machine for a bending needle, or the like (sewing in which the needle enters diagonally) or for sewing in which a penetrating force is required.

As described above, according to the present embodiment, the sewing needle 10 includes a needle tip having a shape in which the tip of a cone is cut off at an angle, and the needle tip has a flat surface 16 that is inclined with respect to the center line X of the sewing needle 10. Is formed. If such a sewing needle 10 is used, the needle tip can easily bite into the sewing object 20 by utilizing the flat surface 16.

Further, since the sewing needle 10 can be manufactured only by diagonally cutting the tip of the needle manufactured in a normal manufacturing process, it is easy to process and can be manufactured at low cost.

If the flat surface 16 is angled too much with respect to the taper angle of the cone, the bite is improved, but there is a problem that the penetration performance is lowered and the needle hole mark is increased. Therefore, the angle and size of the flat surface 16 need to be set in consideration of conditions such as the angle and hardness of the sewing object 20. In this regard, according to the sewing needle 10 of the present embodiment, since the sewing needle 10 having various settings can be easily manufactured, the angle and size of the flat surface 16 can be easily adjusted. Therefore, it is possible to easily manufacture the sewing needle 10 in which the needle flow is prevented, the penetrating force is maintained, and the needle hole trace is inconspicuous.

10,10'Sewing needle 11,11'Needle tip 13,13'Needle trunk 14,14'Needle tip 15,15'Cone 16 Flat surface 20 Sewing object 21 Surface 30 Sewing machine 31 Needle support 32 Drive part X center line

Claims (3)

A sewing needle that is attached to a sewing machine and used.
A needle tip having a shape in which the tip of the cone is cut off at an angle is provided, and a flat surface inclined with respect to the center line of the cone is formed on the needle tip.
The angle of the acute angle formed by the center line of the cone and the flat surface is formed so as to be larger than the angle of the acute angle formed by the center line of the cone and the tapered surface of the cone. The characteristic sewing needle. The sewing needle according to claim 1, wherein the tip of the sewing needle is located at a position eccentric with respect to the center line of the cone. In sewing needles used by attaching to sewing machines
By cutting the tip of the sewing needle formed in a conical shape diagonally, a flat surface inclined with respect to the center line of the cone is formed at the needle tip.
The feature is that the angle of the acute angle formed by the center line of the cone and the flat surface is larger than the angle of the acute angle formed by the center line of the cone and the tapered surface of the cone. How to make a sewing needle.

Images