EP2896732B1 - Sewing needle with double cording - Google Patents

Description

The invention relates to a sewing needle for a sewing machine, which can thus also be referred to as Maschinennähnadel. The sewing needle has a needle body having at one end a holding portion for clamping the sewing needle in a corresponding holding device of the sewing machine. On the opposite side of the holding portion of the needle body has a working portion which terminates in the needle point. In this working portion of the needle body and a Nadelöhr is arranged, which completely penetrates the needle body and passes through the sewing of the upper thread through.

Sewing needles are often made using a stamping process. In the process, in the direction of the longitudinal axis, following the eye of the needle, a depression, which is called a tip groove, often arises. This top trough is also at EP 1 127 973 B1 present and made deeper against the two sidewalls of the eye of the needle, so that the sewing thread slides over a fluke or edge between the tip groove and the side wall of the needle eye upon a change of the sewing direction. This can lead to a twist displacement of the sewing thread.

Out EP 1 127 973 B1 is a sewing needle for multidirectional sewing known. The sewing needle has an elongated eye of the needle, which passes through the needle body and is bounded by two opposite side walls. The needle body extends along a longitudinal axis. In order to preserve the thread guided through the eye of the needle when sewing, the two side walls are curved concavely viewed at their side wall edges in the direction of the longitudinal axis. If the thread emerges obliquely or laterally from the eye of the needle, it will guided over one of the two concave lowered side walls of the needle eye. By this measure a swirl displacement of the suture should be avoided. The twist of the suture should only slightly or not be changed when running the thread on the side wall, thereby avoiding sewing errors and a thread conservation should be achieved.

DE 10 2009 004 033 A1 describes a sewing needle for a sewing machine, which has a groove extending in the direction of the longitudinal axis in the needle body on the needle tip opposite side, which opens into the needle eye. At a point in front of the mouth of the groove in the eye of the needle, this has a relative to the longitudinal axis of the needle body angled section. By this angled groove, the pressing force acting on the sewing thread in the area of the needle eye, in the direction of the impact of the suture to be oriented in order to achieve unthreading of the suture.

DE 86 32 106 U1 describes a tufting needle, wherein the needle tip is offset in the transport direction of the backing with respect to the needle axis. This is to avoid that when piercing the backing of the previously deposited thread is pierced due to vibrations of the tufting needle and thus damaged. The tufting needle may also have a thread groove which extends obliquely from the needle eye obliquely to the longitudinal axis of the needle and ends above the needle point. This is intended to deflect the thread from the longitudinal axis of the needle where the needle point is located.

In the GB 703 934 A described needle is specially designed for use in sewing a shoe. The needle is designed without a needle eye and has in the needle body in a working area a recess, whereby a hook-like projection is formed. The needle is stung through the fabric. With this projection, a thread loop can be taken similar to crocheting, pulled through the fabric and a thread loop on the other side of the fabric. This needle is thus specially designed to execute a stitch type 101 according to DIN 61400: 2002-04.

Starting from this prior art, it can be regarded as an object of the present invention to provide a sewing needle for a sewing machine which has sufficient or improved stability in the region of the needle eye and avoids or minimizes a twist displacement of the sewing thread.

This object is achieved by a sewing needle with the features of claim 1.

The sewing needle has a needle body extending along a longitudinal axis with a holding portion and a working portion. The holding portion and the working portion are provided at opposite end portions of the needle body. The holding section is used for clamping the sewing needle in a corresponding holding or clamping device of the sewing machine. Within the working section, the needle body tapers towards the point of the needle. There is also a needle eye in the working section, which completely penetrates the needle body from a front side to a back side of the needle body in a transverse direction and through which the upper thread is passed for sewing. The bottleneck is bounded by two sidewalls facing each other in a lateral direction which is oriented perpendicular to the longitudinal axis and to the transverse direction.

As viewed in the direction of the longitudinal axis, a yarn channel is introduced into the front side of the needle body between the needle eye and the needle tip. The thread groove forms a Cordierung. The thread groove is located between the needle eye and the needle tip and has two thread groove mouths, which are arranged on different sides of a first longitudinal center plane through the needle body. Preferably, the thread groove or the cordation formed thereby is arranged symmetrically with respect to this first longitudinal center plane through the needle body. The first longitudinal center plane extends along the longitudinal axis of the needle body and in the transverse direction. The transverse direction is aligned at right angles to the longitudinal axis. At the two yarn channel openings, the recessed towards the outer contour of the needle body thread groove adjacent to the outer contour. The thread channel mouths form transition points at which the inner surface of the yarn channel adjoins the outer contour surface of the needle body. The yarn channel opens at a distance from the two yarn channel openings at a lower edge of the needle eye in the Nadelöhr.

As a result of this configuration of the sewing needle, the thread runs during the sewing process from the sewing material through one of the two thread groove openings into the thread groove and finally through the eye of the needle, at least when the sewing needle is located above the sewing material. During or after the piercing of the material, the thread is pulled out of the thread groove and in the Nadelöhr of the needle tip and the thread groove away. However, the position of the thread groove can ensure that the thread remains within the thread groove at least during the largest part of the needle stroke movement - and at least when the sewing needle has a distance from the sewing material and / or during the material transport. Through the yarn channel is a twisting or Entzwirnen the thread and thus a twist displacement avoided. The side walls delimiting the needle eye on the sewing needle body can be dimensioned sufficiently large in the transverse direction in order to ensure the stability of the sewing needle in the region of the needle eye. Although the sewing thread is pushed out of the thread groove on the side wall of the Nadelöhrs when piercing the material. However, it has been found that this phase of the sewing process has little effect on the twist displacement of the thread, so that correspondingly enlarged side walls can be provided for stabilizing the sewing needle without significant negative thread influence. In order to avoid the swirl displacement, the thread groove is present.

In one embodiment, the distance between the two yarn channel openings in a side direction perpendicular to the first longitudinal center plane at least at some and preferably at all points greater than the width of the yarn channel in the lateral direction at the immediately adjacent to the needle eye point. It is possible, for example, that a dimension of the yarn groove in the lateral direction at least partially increases with increasing distance from the needle eye. The dimension of the yarn channel in the lateral direction S corresponds in each case to the largest possible dimension.

The thread groove mouths are located on different sides with respect to the first longitudinal center plane. The thread groove may preferably be formed symmetrically with respect to the first longitudinal center plane. This makes it possible to reverse the direction of transport of the sewing material or the sewing direction and to achieve the desired yarn protection in at least two directions. The weakening of the needle body in a region between the needle eye and the needle tip through the thread groove with the two thread channel mouths can be accepted. It has demonstrated that this will not cause any negative vibration and stability impairments of the sewing needle. On the contrary, by strengthening the needle body on the two side walls of the eye of the needle, an overall much more stable sewing needle is achieved and no or at most insignificant twist displacement of the thread is permitted.

Preferably, the thread groove has, following the needle eye, a channel section which extends in particular in the direction of the longitudinal axis. This channel section opens into the eye of the needle at the lower edge of the needle eye, which represents the edge of the needle eye closest to the needle tip. The gutter section can preferably be delimited on both sides of the first longitudinal center plane by a respective side wall region of a side wall delimiting the needle eye. The side walls delimiting the eye of the needle accordingly each have a side wall region which continues along the groove section and delimits it in the lateral direction. The width of this channel section in the lateral direction can be constant or, starting at the bottleneck, become larger, at least in sections, as the distance from the eye of the needle increases.

The yarn channel and thus also the gutter section has a channel bottom or channel bottom. This channel bottom can be formed by a connecting line of the vertices of the cross-sectional profiles of the thread groove or the channel section. Preferably, the channel bottom of the channel section is inclined in the direction of the longitudinal axis of the needle body. In particular, the distance of the channel bottom of the channel section decreases along the longitudinal axis of the needle eye in the direction of the needle tip down.

It may also be advantageous if the distance of the channel bottom of the thread groove from a second longitudinal center plane at any point is greater than immediately adjacent to the bottleneck. The second longitudinal center plane is aligned at right angles to the first longitudinal center plane and extends along the longitudinal axis and in the lateral direction.

The needle body is preferably made in one piece from a uniform material without seam and joint. It may for example be made of an at least partially cylindrical output element made of metal by an embossing process.

The thread groove preferably has two end sections, which, on the one hand, adjoin the channel section and each have a thread groove mouth. Each end section is in particular stepped and / or edged into the gutter section. The two end portions are arranged in a preferred embodiment on opposite sides of the first longitudinal center plane. Along the first longitudinal median plane, the two end sections can be separated from one another by a protrusion. The survey is preferably edge and / or continuously in the two end portions of the yarn channel over. The inner surfaces of the end portions thus go into the surface of the survey without the formation of a step or edge. This allows a thread gently from the one end portion slide over the survey in the other end portion when the transport direction of the sewing material or the sewing direction changes. The survey is preferably convex and arranged symmetrically to the first longitudinal center plane. In particular, a vertex of the convex curvature of the survey can be arranged on the longitudinal center plane.

In a preferred embodiment, the end portions of the thread groove open in a tapered region of the work section. Thus, the end sections of the thread groove adjoin the outer contour surface of the needle body in the area tapering towards the needle tip at their respective end opposite the channel section. In addition, the channel section may also be arranged at least partially in the region of the working section of the needle body which tapers towards the needle tip.

The channel section has a width in the lateral direction that is greater than the width of the end sections. The width of the end sections of the thread groove is measured transversely to the thread groove running direction or to the thread guiding direction. The thread guide direction or thread groove course direction of the two end sections is aligned obliquely to the first longitudinal center plane. The width of the end portions or the gutter portion is measured in each case at the widest point, for example at the point at which the gutter portion or the respective end portion adjoins the outer contour surface of the needle body.

In a preferred embodiment, at least the two end sections of the thread groove or the entire thread groove run through the needle body only on one side of a second longitudinal center plane. By this configuration, it is possible to produce the sewing needle by a stamping process or another forming process from a blank. In a modification to this, the yarn channel and in particular its end portions could enforce the second longitudinal center plane. In this embodiment, the sewing needle can be produced by a machining production process or a primary molding process.

It is advantageous if the two arranged on opposite sides of the first longitudinal center plane and The side walls bounding the eye of the needle each adjoin the outside core surface of the needle body at a side wall edge. The side wall edge has, at least in sections, a greater distance from the second longitudinal center plane than the point furthest from the second longitudinal center plane and / or the furthest point of the two yarn channel openings. The risk of needle breaks in the area of the eye of the needle is thereby considerably reduced. Preferably, this side wall edge has at least one section which runs parallel to the longitudinal axis of the needle body and / or is convexly curved in the direction of the longitudinal axis and in particular does not have a concavely curved course in the direction of the longitudinal axis.

In a preferred embodiment, the needle body in the direction of its longitudinal axis adjacent the Nadelöhr a gripper recess. The gripper recess is preferably formed symmetrically to the first longitudinal center plane. The gripper recess is arranged with respect to the second longitudinal center plane on the thread groove openings of the two end portions in the needle eye opposite side.

• Figur 1 ein Ausführungsbeispiel einer erfindungsgemäßen Nadel in perspektivischer Darstellung,
• Figur 2 den Arbeitsabschnitt des Nadelkörpers der Nadel aus Figur 1 in einer Seitenansicht in Seitenrichtung,
• Figur 3 den Arbeitsabschnitt aus Figur 2 in einer Ansicht in Querrichtung,
• Figur 4 den Arbeitsabschnitt aus Figuren 2 und 3 in einem Schnittbild gemäß Schnittlinie IV-IV in Figur 3,
• Figur 5 ein Schnittbild durch den Arbeitsabschnitt aus den Figuren 2 bis 4 gemäß der Schnittlinie V-V in Figur 3,
• Figur 6 eine Ansicht des Nadelkörpers gemäß der Figuren 1 bis 5 entlang der Längsachse L des Nadelkörpers auf die Nadelspitze,
• Figur 7 eine Teildarstellung des Arbeitsabschnittes in der Ansicht gemäß Figur 3,
• Figur 8 ein Schnittbild durch den in Figur 7 dargestellten Teil des Arbeitabschnittes gemäß Schnittlinie VIII-VIII,
• Figur 9 den Teil des Arbeitsabschnittes aus den Figuren 7 und 8 in einer Seitenansicht in Seitenrichtung,
• Figuren 10 bis 14 jeweils eine schematische Darstellung einer Position der Nähnadel und des Fadens während dem Nähen,
• Figur 15 ein weiteres Ausführungsbeispiel einer erfindungsgemäßen Nadel in perspektivischer Darstellung,
• Figur 16 den Arbeitsabschnitt des Nadelkörpers der Nadel aus Figur 15 in einer Seitenansicht in Seitenrichtung,
• Figur 17 den Arbeitsabschnitt aus Figur 16 in einer Ansicht in Querrichtung,
• Figur 18 den Arbeitsabschnitt aus Figuren 16 und 17 in einem Schnittbild gemäß Schnittlinie XVIII-XVIII in Figur 17,
• Figur 19 ein Schnittbild durch den Arbeitsabschnitt aus den Figuren 16 bis 19 gemäß der Schnittlinie XIX-XIX in Figur 17 und
• Figur 20 eine Ansicht des Nadelkörpers gemäß der Figuren 15 bis 19 entlang der Längsachse L des Nadelkörpers auf die Nadelspitze.

Advantageous embodiments of the invention will become apparent from the dependent claims, the description and the drawings. The description is limited to essential features of the invention. Hereinafter, preferred embodiments of the invention will be explained in detail with reference to the accompanying drawings. Show it:

• FIG. 1 An embodiment of a needle according to the invention in a perspective view,
• FIG. 2 the working portion of the needle body of the needle FIG. 1 in a side view in side direction,
• FIG. 3 the work section FIG. 2 in a transverse view,
• FIG. 4 the work section FIGS. 2 and 3 in a sectional view along section line IV-IV in FIG. 3 .
• FIG. 5 a sectional view through the working section of the FIGS. 2 to 4 according to the section line VV in FIG. 3 .
• FIG. 6 a view of the needle body according to the FIGS. 1 to 5 along the longitudinal axis L of the needle body to the needle tip,
• FIG. 7 a partial view of the working section in the view according to FIG. 3 .
• FIG. 8 a sectional view through the in FIG. 7 represented part of the working section according to section line VIII-VIII,
• FIG. 9 the part of the working section from the FIGS. 7 and 8 in a side view in side direction,
• FIGS. 10 to 14 each a schematic representation of a position of the sewing needle and the thread during sewing,
• FIG. 15 another embodiment of a needle according to the invention in a perspective view,
• FIG. 16 the working portion of the needle body of the needle FIG. 15 in a side view in side direction,
• FIG. 17 the work section FIG. 16 in a transverse view,
• FIG. 18 the work section FIGS. 16 and 17 in a sectional view according to section line XVIII-XVIII in FIG. 17 .
• FIG. 19 a sectional view through the working section of the FIGS. 16 to 19 according to the section line XIX-XIX in FIG. 17 and
• FIG. 20 a view of the needle body according to the FIGS. 15 to 19 along the longitudinal axis L of the needle body to the needle point.

In the FIGS. 1 to 9 An embodiment of a sewing needle 20 for use in a sewing machine is illustrated. The sewing needle 20 has a needle body 21 extending along a longitudinal axis L. The needle body 21 is made in one piece from a uniform material without seams and joints. It is preferably made of metal or a metal alloy. As in the FIGS. 1 or 15 illustrated, the needle body 21 at one end portion has a holding portion 22 which is cylindrical, for example. The holding section 22 serves to clamp the sewing needle 20 in a clamping device of the sewing machine. At the end region opposite the holding section 22, the needle body 21 has a working section 23. In the working section 23 there is a tapered region 24, in which the needle body 21 tapers towards the needle tip 25. The working section 23 can, as in FIG. 1 can be connected via a shaft portion 26 with the holding portion 22. In the shaft section 26, the needle body 21 is, for example, at least partially cylindrical and may expand towards the retaining section 22.

In the longitudinal axis L intersect a first longitudinal center plane M1 and a second longitudinal center plane M2, which are aligned at right angles to each other. The first longitudinal center plane M1 is stretched by the longitudinal axis L and a transverse direction Q. The second longitudinal center plane M2 is spanned by the longitudinal axis L and a lateral direction S. The lateral direction S and the transverse direction Q are oriented at right angles to each other.

In the working area 23, the needle body 21 has a needle eye 30. The needle eye 30 passes through the needle body 21 in the transverse direction Q completely. Thus, an upper thread for sewing in the transverse direction Q can be threaded through the needle eye 30 become. The needle eye 30 has in the direction of the longitudinal axis L a larger dimension than in the lateral direction S. It arises, so to speak, a kind of slot. The needle eye 30 is bounded in the lateral direction S by two opposing side walls 31. The side walls 31 extend according to example at least in sections in a plane parallel to the longitudinal axis L and the transverse direction Q. Each side wall 31 has on a front side 32 of the needle body 21, a first side wall edge 33 and on one of the front 32 in the transverse direction Q opposite back 34 of the needle body 21 a second side wall edge 35. The two side wall edges 33, 35 extend substantially parallel to the longitudinal axis L or convexly arched away from the second longitudinal center plane M2, at least in the region of the needle eye 30 in which the needle eye 30 in the transverse direction Q has a continuous, free space profile 36 ( FIGS. 4 and 18 ).

The two side walls 31 delimiting the needle eye 30 are connected to each other at the needle tip 25 side by a lower transverse surface 40 and on the opposite side by an upper transverse surface 41. The clearance space 36 is thus limited by the two transverse surfaces 40, 41 and the two side walls 31. The transverse surfaces 40, 41 are curved in plan view of the Nadelöhr 30, so seen in the transverse direction Q ( Figures 3 and 17 ). In addition, the transverse surfaces 40, 41 may have a curved course at least in sections in each sectional plane which is arranged parallel to the first longitudinal center plane M1 ( FIGS. 4 and 18 ).

In the tapered region 24 of the working portion 23, a thread groove 39 is introduced into the front side 32 of the needle body 21. The thread groove is arranged symmetrically in the embodiments shown here with respect to the first longitudinal center plane M1. The thread trough 39 has adjacent to the Nadelöhr 30 a channel portion 39 a. The gutter section 39a merges into the needle eye 30 on the lower side of the needle eye 30 assigned to the tip 25. In other words, the channel section 39a forms a lower edge 45 with the lower transverse surface 40.

The thread groove 39 also has two thread groove openings 42, 43. In the embodiments described here, two end sections 39b, 39c of the thread groove 39, each with a thread groove opening 42 or 43, adjoin the channel section 39a. The thread groove 39 is inserted into the needle body 21 opposite an envelope or outer contour surface A of the working section 23 of the needle 20 and opens at one end into the needle eye 30 and at a distance to the two thread troughs 42, 43 in the outer contour surface A. The through the Thread channel formed Cordierung can be referred to as Doppelcordierung because of the two Fadenrinnenmündungen 42, 43.

The outer contour surface A of the needle body 21 is predetermined in the working section 23 by the enveloping contour. This contour describes an area that the working section 23 would have if the needle eye 30 and the thread groove 39 were not present. The outer contour surface A is in the Figures 2 . 16 and 18 only shown schematically.

It should be noted at this point that the term "edge" in the present development is to be understood as meaning not a sharp, angled edge. Rather, the edges, for example, the lower edge 45 or the side wall edges 33, 35 rounded or provided with a radius to form no sharp edges on the needle body 21, which damage the thread could.

In the FIGS. 4 and 18 the working section 23 of the needle body 21 is cut along the first longitudinal center plane M1. The thread groove 39 has there a crest line which extends along the course direction of the thread groove 39 and the thread guide direction and forms a channel bottom 46. In the channel section 39a, the apex line extends from the lower edge 45 along the first longitudinal center plane M1. The channel bottom 46 extends inclined in the region of the channel section 39a with respect to the second longitudinal center plane M2. The distance of the channel bottom 46 from the longitudinal axis L or from the second longitudinal center plane M2 decreases in the region of the channel section 39a in the direction of the longitudinal axis L starting from the needle eye 30 and the lower edge 45 to the needle tip 25 from.

In the embodiment of the sewing needle 20 according to the FIGS. 15 to 20 is the channel bottom 46 in the lateral direction S preferably just along the entire yarn channel 39. In a modification to this, he could also - differently than shown - be convexly curved.

Each of the two side walls 31 has a side wall region 47 following the clearance 36. The two side wall portions 47 delimit the channel portion 39a following the lower edge 45 in the lateral direction S. The side wall portion 47, for example edge and infinitely into the adjacently arranged to the clearance 36 of the needle eye 30 portion of the side wall 31 via. The upper side wall edge 33 continues in the side wall region 47 in an edge section 48, which approaches the second longitudinal center plane M2 as the distance to the needle point 25 decreases. The edge portion 48 has, for example, a curved course. His distance to the second longitudinal center plane M2 is smaller at each point than the distance of the first side wall edge 33 from the second longitudinal center plane M2 in the region of the clearance space profile 36 (FIG. 8).

Following the channel section 39a, the thread channel 39 has two end sections 39b, 39c, each of which has one of the two thread channel openings 42, 43. By way of example, the two end sections 39b, 39c extend on different sides of the first longitudinal center plane M1, which can thus serve as a separating surface between the two end sections 39b, 39c.

In the one embodiment according to the FIGS. 1 to 9 are the two end portions 39b, 39c separated by a survey 51 in the region of the first longitudinal center plane M1. The elevation 51 is preferably executed symmetrically to the first longitudinal center plane M1 and designed as a convex elevation or as a bump, for example. In the transition to the two end portions 39b, 39c, the elevation 51 is rounded and has neither edges nor steps. Therefore, during sewing, a thread can slide without damage from one end section 39b, 39c to the other end section 39c or 39b.

The bump 51 between the two end portions 39b, 39c of the first embodiment ( FIGS. 1 to 9 ) does not protrude through this outer contour surface A.

In the transverse direction Q, in plan view of the elevation 51 whose width decreases in the lateral direction S along the longitudinal axis L of the needle tip 25 away continuously. Likewise, the height of the bump 51 in the transverse direction Q along the longitudinal axis L decreases away from the needle tip 25. The elevation 51 has a vertex 51a on which the elevation 51 has the greatest distance from the second longitudinal center plane M2. The vertex 51a is arranged in the first longitudinal center plane M1. The distance of the apex 51a in the transverse direction Q from the second longitudinal center plane M2 is smaller by a difference D than the distance of the first side wall edges 33 in the transverse direction Q from the second longitudinal center plane M2 (FIG. FIG. 8 ). The distance of the first side wall edges 33 is measured in the region of the opening of the needle eye 30, ie in the region of the clearance 36. The distance of the second side wall edges 35 from the second longitudinal center plane M2 is preferably also greater than the distance of the apex 51a from the second longitudinal center plane M2 and may for example be exactly the same as the distance of the first side wall edges 33 from the second longitudinal center plane M2. As a result, it is possible in the transverse direction Q to reach large-dimensioned side walls 31, which give the sewing needle 20 good stability in the region of the needle eye 30.

In contrast to the first embodiment according to the FIGS. 1 to 9 are the two end portions 39b, 39c in the second embodiment according to the FIGS. 15 to 20 not separated by a survey 51. Rather, the channel bottom 46 is preferably continuous in the lateral direction S, so that the two end sections 39b, 39c at the first longitudinal mid-plane M1 merge into one another continuously steplessly and without edges. The two thread groove openings 42, 43 thus abut each other directly in the first longitudinal center plane M1. In plan view along the transverse direction Q on the working section 23, therefore, the thread groove 39 has a contour which widens in the lateral direction S along the first channel portion 39a starting from the needle eye 30 in the direction of the needle tip 25 out first. At the point where the edge portions 48 of the side wall portions 47 merge into the channel bottom 46, begin the two end portions 39b, 39c. The two end sections 39b, 39c have in common a tapering from the channel portion 39a to the needle tip 25 contour. The thread groove 39 thereby has a dimension in the lateral direction S, which decreases starting from the channel section 39a along the two end sections 39b, 39c in the direction of the needle tip 25. Characterized the thread groove 39 has at the two end portions 39b, 39c viewed in the transverse direction Q triangular contour, the side lines of this triangle can be curved. The thread groove 39 has in this embodiment at the transition point between the channel portion 39a to the two end portions 39b, 39c out in the lateral direction S, the largest dimension.

The elevation 51 forms the essential difference between the two embodiments illustrated and described here. In the second embodiment according to the FIGS. 15 to 20 the elevation 51 between the two end portions 51 is removed and replaced by a continuous inner surface of the thread groove. Otherwise, the two embodiments of the sewing needle 20 are identical.

The yarn channel 39 is open to the front 32. At the two thread channel openings 42, 43, the thread groove 39 additionally opens in the lateral direction S on both sides of the first longitudinal center plane M1. In the exemplary embodiments, the thread trough 39 or at least the two end sections 39b, 39c, viewed in relation to the second longitudinal center plane M2, are provided exclusively on one side. The thread groove 39 thus does not pass through the second longitudinal center plane M2, but can reach the second longitudinal center plane M2.

In a modification to this, it is also possible that at least the two end portions 39b, 39c, the second longitudinal center plane M2 enforce what is highly schematized in FIG. 9 is illustrated by the dashed line. As an extension of the last-mentioned embodiment, it is even possible for the entire yarn channel 39, viewed from the front side 32, to lie on the other side of the second longitudinal center plane M2. Additionally or alternatively, the gutter section 39a can pass through the longitudinal center plane M2.

In the preferred embodiment, however, the second longitudinal center plane M2 is penetrated by the thread groove 39 at any point and possibly touched. This has the advantage that the sewing needle 20 can be made very easily by forming, in particular embossing, from a blank.

The thread groove 39 represents a Cordierung a sewing needle 20, which is configured symmetrically in the illustrated embodiment to the first longitudinal center plane M1. Preferably, the sewing needle 20 is generally symmetrical to the first longitudinal center plane M1.

In FIG. 3 is schematically the width of the Cordierung or the thread groove 39 at different points of the first embodiment according to the FIGS. 1 to 9 shown. The gutter portion 39a has a width B1 in the lateral direction S which is at least as large as the minimum distance between the two side walls 31 in the lateral direction S. The two end portions 39b, 39c each have a width B2 which is smaller than the width B1 of the gutter portion 39a. The width B2 of each end portion 39b, 39c is measured at right angles to a yarn guiding direction F. The yarn guide direction F results from the direction of the respective edge portion 48 which is adjacent to the respective end portion 39b, 39c.

On the thread groove 39 opposite side of the needle eye 30, a gripper recess 53 is present in the working section 23 on the front side 32 of the needle body 21. In the region of the gripper recess 53, the needle body 21 thus has a smaller thickness in the transverse direction Q than at the two regions adjoining the gripper recess 53 along the longitudinal axis L. Through this gripper recess 53, a gripper of a sewing machine can better grip a top thread running along the front side 32 of the needle body 21 and loop around the lower thread. The gripper recess 53 has two chamfers 54, which are arranged symmetrically with respect to the first longitudinal center plane M1 ( Figures 3 and 5 or 17 and 19). However, it is also possible to provide the chamfer only on one side or to make the recess otherwise asymmetrical to the longitudinal center plane M1. The sewing needle 20 can cooperate with grippers of a sewing machine, which, viewed in the lateral direction S seize the thread from one side or the other. As a result, the sewing needle 20 is also suitable for use in a sewing machine with two sewing needles. Due to the symmetrical design of the sewing needle 20 relative to the first longitudinal center plane M1, it can not be confused even when used in sewing machines with two needles. In such a sewing machine, two of the described sewing needles 20 can be used without the risk of confusion.

Based on FIGS. 10 to 14 The use of the sewing needle 20 in a sewing machine when sewing a sewing material 60 will be explained. This explanation applies to all embodiments, even if the FIGS. 10 to 14 By way of example, the first embodiment of the sewing needle 20 according to the FIGS. 1 to 9 demonstrate.

In FIG. 10 the needle 20 has a distance to the fabric 60. The upper thread 61 extends from the last stitch in the fabric 60 through the needle eye 30 of the needle 20. The fabric 60 is moved in a first transport direction T1. The first transport direction T1 is aligned parallel to the lateral direction S of the needle 20. In this case, the needle 20 moves along its longitudinal axis L down to the fabric 60 back. At least until the piercing of the needle tip 25 into the sewing material 60, the upper thread 61 remains within one of the two thread groove mouths 42, 43 and, for example, in the first thread groove mouth 42. This prevents undesired twisting of the upper thread 61.

In the FIG. 12 has the needle 20 after its return stroke from the fabric 60 again in FIG. 10 illustrated starting position. It is now assumed that the transporting direction of the sewing material 60 is reversed. For the further sewing process, the sewing material is moved in a second transport direction T2, which is opposite to the first transport direction T1. In this reversal of direction extending from the needle eye 30 to the fabric 60 thread section of the upper thread 61 of the first thread groove mouth 42 - possibly on the existing elevation 51 - in the second thread groove mouth 43 is moved ( Figures 13 and 14 ). In this case, the upper thread 61 slides over the edge and continuously running convex elevation 51 between the two end portions 39b, 39c, if this is present. A swirl displacement of the upper thread 61 is at least substantially avoided. The upper thread 61 is moved over no angled sharp edge or step, which coincides with the extension direction of the upper thread 61 approximately, which can lead to a Aufzwirnen or Entzwirnen the upper thread 61.

After performing the reversal of the transport direction, the sewing material 60 is then in the second transport direction T2 moves and the sewing needle 20 performs a lifting movement along its longitudinal axis L. Analogous to that in the FIGS. 10 and 11 In this case, the upper thread 61 remains in the second thread groove mouth 43, as long as the sewing needle 20 has not yet pierced into the sewing material 60.

The sewing needle 20 is thus provided for sewing in at least two example opposite transport directions T1, T2.

Sewing needles according to the invention are preferably equipped with a displacement tip or a cutting tip.

The invention relates to a sewing needle 20 for use in a sewing machine. The sewing needle 20 has a working portion 23 with a needle eye 30 and a tapered to a needle tip 25 area 24. The needle eye 30 passes through a needle body 21 of the sewing needle 20 in a transverse direction Q perpendicular to a longitudinal axis L of the needle body 21. On a front side 23rd of the needle body 21 is recessed relative to the outer contour of the needle body 21 introduced a Cordierung extending from the needle eye 30 in the direction of the needle tip 25 out. The Cordierung is formed by a thread groove 39 with two thread channels 42, 43. The Cordierung is preferably carried out symmetrically to a first longitudinal center plane M1, which is spanned by the longitudinal axis L and the transverse direction Q. The thread groove 39 has a channel section 39a following the needle eye 30. At a distance from the needle eye 30, the thread groove 39 has two end sections 39b, 39c, each with a thread groove mouth 42, 43. A convex, rounded elevation 51 may, in one embodiment, separate the two end portions 39b, 39c from each other. The elevation 51 is preferably symmetrical to the first longitudinal center plane M1 executed.

LIST OF REFERENCE NUMBERS

20

sewing needle

21

needle body

22

holding section

23

working section

24

rejuvenating area

25

pinpoint

26

shank portion

30

eye of a needle

31

Side wall

32

front

33

first sidewall edge

34

back

35

second sidewall edge

36

Gauge

39

thread groove

39a

Channel cutting

39b

first end section

39c

second end section

40

lower transverse surface

41

upper transverse surface

42

first thread trough mouth

43

second thread trough mouth

45

lower edge

46

channel bottom

47

Sidewall region

48

edge portion

51

survey

51a

vertex

53

gripper recess

54

chamfer

60

workpiece

61

upper thread

A

Outer contour surface

B1

Width of the gutter section

B2

Width of an end section

F

Thread guide direction

L

longitudinal axis

M1

first longitudinal median plane

M2

second longitudinal median plane

Q

transversely

S

lateral direction

T1

first transport direction

T2

second transport direction

Claims (16)

1. Sewing needle (20) for a sewing machine,
   having a needle body (21) extending along a longitudinal axis (L), said needle body having a retaining section (22) for fixing the sewing needle (20) in the sewing machine, and a working section (23) which contains the needle tip (25) of the sewing needle (20),
   having a needle eye (30) arranged in the working section (23) of the needle body (21), said needle eye completely pushing through the needle body (21),
   having a thread groove (39) which is arranged between the needle eye (30) and the needle tip (25), and which leads into the needle eye (30) on a lower edge (45) of the needle eye (30) which is facing towards the needle tip (25), characterised in that
   the thread groove (39) has a first thread groove mouth (42) and a second thread groove mouth (43) that are at a distance from the needle eye (30), said mouths being arranged on different sides of a first longitudinal central plane (M1) through the needle body (21).
2. Sewing needle according to claim 1,
   characterised in that the distance between the two thread groove mouths (42, 43) in a lateral direction (S) at right angles to the first longitudinal central plane (M1) is, at least at certain points, greater than the width of the thread groove (39) in the lateral direction (S) at the point adjoining the needle eye (30).
3. Sewing needle according to claim 1 or 2,
   characterised in that a dimension of the thread groove (39) in a lateral direction (S) at right angles to the first longitudinal central plane (M1) increases from the needle eye (30) in the direction of both thread groove mouths (42, 43).
4. Sewing needle according to one of the preceding claims,
   characterised in that the thread groove (39) has a groove section (39a) which is directly attached to the needle eye (30).
5. Sewing needle according to claim 4,
   characterised in that the groove section (39a) is bordered on opposite sides by a respective side wall region (47) of a side wall (31) that borders the needle eye (30).
6. Sewing needle according to claim 4 or 5,
   characterised in that a groove base (46) of the groove section (39a) approaches the longitudinal axis (L) from the needle eye (30) in the direction towards the needle tip (25).
7. Sewing needle according to one of claims 4 to 6,
   characterised in that the thread groove (39) has two end sections (39b, 39c) which extend between a respective thread groove mouth (42, 43) and the groove section (39a).
8. Sewing needle according to claim 7,
   characterised in that the end sections (39b, 39c) of the thread groove (39) are arranged in a region (24) of the working section (23) that tapers towards the needle tip (25).
9. Sewing needle according to claim 7 or 8,
   characterised in that the width (B2) of the end sections (39b, 39c) is smaller than the width (B1) of the groove section (39a).
10. Sewing needle according to one of claims 7 to 9,
    characterised in that an elevation (51) is present between the two end sections (39b, 39c) of the groove thread (39).
11. Sewing needle according to claim 10,
    characterised in that the elevation (51) passes into both end sections (39b, 39c) of the thread groove (39) without edges.
12. Sewing needle according to claim 10 or 11,
    characterised in that the elevation (51) is curved convexly and has a vertex (51a) on the first longitudinal central plane (M1).
13. Sewing needle according to one of the preceding claims,
    characterised in that the thread groove (39) does not push through a second longitudinal central plane (M2) through the needle body (21), said plane being configured at right angles to the first longitudinal central plane (M1).
14. Sewing needle according to one of the preceding claims,
    characterised in that the needle eye (30) is bordered on opposite sides of the first longitudinal central plane (M1) by a respective side wall (31) which adjoins the outer contour surface (A) of the needle body (21) at a side wall edge (33, 35).
15. Sewing needle according claim 14 and according to one of claims 10 to 12,
    characterised in that the side wall edge (33, 35) has a maximum distance from a second longitudinal central plane (M2) that is configured at right angles to the first longitudinal central plane (M1), said distance being greater than the maximum distance from the elevation (51) to the second longitudinal central plane (M2).
16. Use of the sewing needle (20) according to one of the preceding claims in a sewing machine when sewing a sewing material (60), said sewing material being transported by the sewing machine in at least two transportation directions (T).

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