HK1226109B - Sewing needle with double twist groove - Google Patents

Description

Sewing needle with double twist groove

Technical Field

The present invention relates to a sewing needle for a sewing machine, wherein the needle can therefore also be referred to as a machine sewing needle. The sewing needle comprises a needle body having a retaining portion at one end thereof, said retaining portion being used to clamp the sewing needle into a corresponding retaining arrangement of the sewing machine. On the side opposite the retaining portion, the needle body has a working portion terminating in a needle tip. In this working portion of the needle body, an eyelet is also provided, which extends completely through the needle body and through which an upper thread is passed during the sewing operation.

Background Art

Sewing needles are often manufactured using a stamping process. This process often results in a recessed portion adjacent to the eye of the needle along the longitudinal axis, known as the tip groove. This tip groove, also described in EP 1 127 973 B1, is designed to be deeper relative to the two side walls of the eye of the needle, so that when the sewing direction changes, the sewing thread slips over the flanks or edges between the tip groove and the side walls of the eye of the needle. This can result in twisting and displacement of the sewing thread.

A sewing needle for multi-directional sewing is known from document EP 1 127 973 B1. The sewing needle has an elongated eye that extends through the needle body and is delimited by two opposite side walls. The needle body extends along a longitudinal axis. In order to save thread guided through the eye during the sewing operation, the two side walls are curved concavely at their side wall edges, viewed in the direction of the longitudinal axis. When the thread emerges from the eye at an angle or laterally, it will be guided through one of the two concavely lowered side walls of the eye. Due to this measure, twisting displacements of the sewing thread will be avoided. When the thread moves over the side walls, the twisting effect of the sewing thread should be only minimally changed or not changed, as a result of which sewing errors are avoided and thread is saved.

Document DE 10 2009 004 033 A1 describes a sewing needle for a sewing machine. The needle has a groove in the needle body, on the side opposite the needle tip, extending in the direction of the longitudinal axis, which ends in the eye of the needle. At a point in the eye before the groove ends, the groove has a portion that is inclined at an angle relative to the longitudinal axis of the needle body. Due to this angled groove, the compressive force acting on the sewing thread in the area of the eye of the needle is intended to be directed in the direction of the inclination of the sewing thread, thereby achieving a detwisting of the sewing thread.

Document DE 86 32 106 U1 describes a tufting needle in which the needle tip is offset relative to the needle axis in the direction of feed of the backing. This is to prevent the backing from being pierced by previously applied thread and, therefore, damaged by the oscillation of the tufting needle. The tufting needle may also have a thread groove that extends obliquely from the eye relative to the longitudinal axis of the needle and terminates above the needle tip. This results in the thread being deflected from the longitudinal axis of the needle where the needle tip lies.

The needle described in GB 703 934 A is specifically designed for use in sewing shoes. It lacks an eye and has a recess in the working portion of the needle body, resulting in a hook-shaped projection. The needle pierces the material to be sewn. This projection allows the thread loop to be grasped, similar to crocheting, and pulled on the other side of the sewing material. Therefore, the needle is specifically designed to perform stitch type 101 in accordance with DIN 614:2002-04.

In view of this prior art, the object of the present invention may be seen as providing a sewing needle for a sewing machine which exhibits sufficient or improved stability in the region of the needle eye and, therefore, avoids or minimizes twisting displacements of the sewing thread.

Summary of the Invention

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

The sewing needle comprises a needle body extending along a longitudinal axis, the needle body comprising a retaining portion and a working portion. The retaining portion and the working portion are arranged on opposite end regions of the needle body. The retaining portion is arranged to clamp the sewing needle into a suitable retaining or clamping device of a sewing machine. Within the working portion, the needle body tapers towards the needle tip. Also arranged in the working portion is the eye of the needle, which extends completely through the needle body in a transverse direction from the front side to the rear side of the needle body and through which the upper thread is guided for sewing. The eye of the needle is delimited in a lateral direction by two opposite side walls, which are oriented at right angles to the longitudinal axis and the transverse direction.

Viewed in the direction of the longitudinal axis, a wire groove is provided in the front face of the needle body, between the eye of the needle and the needle tip. The wire groove is a twist groove. The wire groove is located between the eye of the needle and the needle tip and has two wire groove openings, which are arranged on different sides of a first longitudinal center plane passing through the needle body. Preferably, the wire groove or the twist groove formed thereby is arranged symmetrically with respect to the first longitudinal center plane passing through the needle body. The first longitudinal center plane extends along the longitudinal axis of the needle body and in a transverse direction. The transverse direction is oriented at right angles to the longitudinal axis. A wire groove recessed relative to the outer contour of the needle body is adjacent to the two wire groove openings. The wire groove opening forms a transition area where the inner surface of the wire groove is adjacent to the outer contour surface of the needle body. The wire groove terminates at the lower edge of the needle eye in the needle eye at a distance from the two wire groove openings.

Due to this construction of the sewing needle, at least when the sewing needle is above the sewing material, the thread moves from the sewing material through one of the two slot openings in the slot during the sewing operation and eventually passes through the eye of the needle. While or after the sewing material is pierced, the thread is pulled out of the slot and pulled through the needle tip away from the slot in the eye of the needle. However, due to the position of the slot, it is possible to ensure that the thread remains in the slot during the largest part of the needle stroke movement and at least when the needle is at a certain distance from the sewing material and/or when the sewing material is being transported. The slot prevents the thread from twisting or untwisting and, therefore, prevents the thread from being twisted and displaced. The side walls on the sewing needle body that define the eye of the needle can be dimensioned sufficiently large in the transverse direction to ensure the stability of the sewing needle in the area of the eye of the needle. Indeed, when the sewing material is pierced, the sewing thread is pushed out of the thread groove onto the side walls of the needle eye; however, it has been found that this stage of the sewing process has only a very small effect on the twisting displacement of the thread, so that therefore, the enlarged side walls can be provided to stabilize the sewing needle without any appreciable negative impact on the thread. The thread groove is provided to avoid any twisting displacement.

In an exemplary embodiment, the lateral distance between the two thread groove openings is at right angles to the first longitudinal center plane and is greater, at least at some points, and preferably at all points, than the lateral width of the thread groove at a point directly adjacent to the needle eye. In doing so, for example, a dimension of the thread groove can increase in the lateral direction, at least in sections, with increasing distance from the needle eye. The dimension of the thread groove in the lateral direction S accordingly corresponds to the maximum possible dimension.

The thread groove openings are located on different sides relative to the first longitudinal center plane. In doing so, the thread groove can preferably be constructed so as to be symmetrical relative to the first longitudinal center plane. As a result, the conveying direction of the sewing material or the sewing direction can be reversed, and the desired thread saving (threadsparing) along at least two sewing directions can be achieved. Therefore, it is acceptable to weaken the needle body in the area between the needle eye and the needle tip by means of a thread groove with two thread groove openings. It has been found that as a result of this, negative oscillations and impaired stability of the sewing needle do not occur as a result. On the contrary, due to the reinforcement of the needle body on both sides of the side wall of the needle eye, an overall significantly more stable needle is achieved, and no or at most insignificant twisting displacement of the thread is allowed.

Preferably, adjacent to the eye of the needle, the thread groove has a groove portion extending, in particular, in the direction of the longitudinal axis. This groove portion ends in the eye of the needle at the lower edge of the eye of the needle, the lower edge representing the edge of the eye of the needle closest to the needle tip. Preferably, the groove portion can be defined on both sides of the first longitudinal center plane by a side wall region respectively defining the side wall of the eye of the needle. Therefore, the side wall defining the eye of the needle accordingly has an area on the side wall that continues along the groove portion, thereby defining the groove portion in the lateral direction. The width of the groove portion in the lateral direction can be constant or can start from the eye of the needle and increase at least in sections as the distance from the eye of the needle increases.

The wire groove, and therefore the groove portion, also has a groove bottom or groove base. The groove bottom can be formed by a line connecting the vertices of the cross-sectional profile of the wire groove and the groove portion. Preferably, the groove bottom of the groove portion is inclined in the direction of the longitudinal axis. In particular, the distance of the groove bottom of the groove portion decreases along the longitudinal axis from the eye of the needle in the direction toward the needle tip.

Furthermore, it can be advantageous if the groove bottom of the thread groove is not at any point further away from a second longitudinal center plane than at a point directly adjacent to the needle eye. The second longitudinal center plane is aligned at right angles to the first longitudinal center plane and extends along the longitudinal axis and in a lateral direction.

Preferably, the needle body is made of one piece of cohesive material without any seams and joints.For example, the needle body can be made by means of a stamping process from at least one metallic starting element that is at least sectionally cylindrical.

Preferably, the wire trough has two end sections, which, on the one hand, adjoin the trough portion and each have a wire trough opening. Each end section preferably transitions into the trough section without offset and/or edges. In a preferred exemplary embodiment, the two end sections are arranged on opposite sides of a first longitudinal center plane. Along the first longitudinal center plane, the two end sections may be separated from each other by an elevation. Preferably, the elevation transitions into the two end sections of the wire trough without edges and/or offsets. Thus, the inner surface of the end position transitions into the surface of the elevation without forming an offset or edge. As a result, when the feed direction or sewing direction of the sewing material changes, the thread can slide smoothly from one end section to the other via the elevation. Preferably, the elevation is convexly curved and arranged symmetrically with respect to the first longitudinal center plane. In particular, the apex of the convex curve of the elevation may lie on the longitudinal center plane.

In a preferred embodiment, the end portions of the wire groove terminate in the tapering region of the working portion. Thus, the end portions of the wire groove, at their respective ends opposite the groove portion, abut the outer contour surface of the needle body in the region tapering toward the needle tip. Furthermore, the groove portion may also be at least partially disposed in the working portion of the needle body, which tapers toward the needle tip.

In the lateral direction, the groove portion has a width that is greater than the width of the end portion. The width of the end portion of the wire groove is measured transversely to the wire groove extension direction or the wire guiding direction. The wire guiding direction or the wire groove extension direction of the two end portions are oriented obliquely with respect to the first longitudinal center plane. For example, the width of the end portion of the groove portion is measured at the point where the groove portion or the corresponding end portion abuts the outer contour surface of the needle body.

In a preferred embodiment, at least the two end portions of the trough, or the entire trough, extend through the needle body only on one side of the second longitudinal center plane. This configuration allows the sewing needle to be manufactured from a blank using a stamping process or another forming process. In a modification thereof, the trough, and in particular its end portions, can extend through the second longitudinal center plane. In this embodiment, the sewing needle can be produced using a cutting manufacturing process or a forming process.

It is advantageous if the two side walls, which are arranged on opposite sides of the first longitudinal center plane and which define the eye of the needle, adjoin the outer contour surface of the needle body. The side wall edges are at least partially at a greater distance from the second longitudinal center plane than the point of the protuberance at the greatest distance from the second longitudinal center plane and/or than the points of the two wire slot openings at the greatest distance. This embodiment gives the needle body particularly good stability in the area of the eye of the needle. As a result, the risk of needle breakage in the area of the eye of the needle is significantly reduced. Preferably, the side wall edge has at least one section which extends parallel to the longitudinal axis of the needle body and/or which is convexly curved in the direction of the longitudinal axis and, in particular, does not have a concave curvature in the direction of the longitudinal axis.

In a preferred exemplary embodiment, the needle body has a gripping recess near the eye of the needle along its longitudinal axis. Preferably, the gripping recess is symmetrical with respect to the first longitudinal center plane. The gripping recess is arranged on the side of the eye of the needle opposite the thread groove openings of the two end portions relative to the second longitudinal center plane.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantageous embodiments of the invention can be inferred from the dependent patent claims, the description and the drawings. This description is limited to the essential features of the invention. In the following, preferred exemplary embodiments of the invention are explained in detail with reference to the drawings. They show:

FIG1 shows a perspective view of an exemplary embodiment of a needle according to the present invention;

FIG2 shows a side view in a lateral direction of the working part of the needle body of the needle according to FIG1 ;

FIG3 shows a view of the working part according to FIG2 in a transverse direction;

FIG4 shows a cross-sectional view of the working portion according to FIG2 and FIG3 along the intersection line IV-IV in FIG3;

FIG5 shows a cross-sectional view of the working portion as shown in FIG2 to FIG4 along the intersection line V-V in FIG3 ;

FIG6 shows a view of the needle body according to FIG1 to FIG5 along the longitudinal axis L of the needle body toward the needle tip;

FIG7 shows a partial illustration of the working portion in the view as shown in FIG3 ;

FIG8 shows a cross-sectional view of a portion of the working portion shown in FIG7 taken along the intersection line VIII-VIII;

FIG9 shows a side view in a lateral direction of a portion of the working part according to FIG7 and FIG8;

10 to 14 each show a schematic diagram of the position of a sewing needle and thread during a sewing operation;

FIG15 is a perspective view of another exemplary embodiment of a needle according to the present invention;

FIG16 shows a side view in a lateral direction of the working portion of the needle body of the needle according to FIG15 ;

FIG17 shows a view of the working portion according to FIG16 in a transverse direction;

FIG18 shows a cross-sectional view of the working portion according to FIG16 and FIG17 along the intersection line XVIII-XVIII in FIG17 ;

FIG19 shows a cross-sectional view of the working portion according to FIG16 to FIG19 taken along the intersection line XIX-XIX as shown in FIG17; and

FIG. 20 shows a view of the needle body according to FIG. 15 to FIG. 19 along the longitudinal axis L of the needle body toward the needle tip.

DETAILED DESCRIPTION

Figures 1 to 9 show an exemplary embodiment of a sewing needle 20 for use in a sewing machine. The sewing needle 20 has a needle body 21 extending along a longitudinal axis L. The needle body 21 is made of a cohesive material without seams or joints. Preferably, the needle body comprises metal or a metal alloy. As shown in Figures 1 or 15 , the needle body 21 has a retaining portion 22 at one end, which may be cylindrical, for example. The retaining portion 22 is configured to hold the sewing needle 20 in place in a first clamping arrangement of the sewing machine. In the end opposite the retaining portion 22, the needle body 21 has a working portion 23. The working portion 23 includes a tapered region 24, where the needle body 21 tapers toward a needle tip 25. As can be seen in Figure 1 , the working portion 23 can be connected to the retaining portion 22 via a shank 26. In the shank 26, the needle body 21 is at least partially cylindrical and may widen toward the retaining portion 22.

The first longitudinal center plane M1 and the second longitudinal center plane M2 are oriented at right angles to each other and intersect in the longitudinal axis L. The first longitudinal center plane M1 is generated by the longitudinal axis L and the transverse direction Q. The second longitudinal center plane M2 is generated by the longitudinal axis L and the lateral direction S. The lateral direction S and the transverse direction Q are oriented at right angles to each other.

In the working portion 23, the needle body 21 has an eye 30. The eye 30 extends completely through the needle body 21 in the transverse direction Q. Therefore, the upper thread can be threaded through the eye 30 close to the transverse direction Q. In the direction of the longitudinal axis L, the size of the eye 30 is larger than in the lateral direction S. It can be said that a type of elongated hole is formed. In the lateral direction S, the eye 30 is defined by two opposite side walls 31. According to the example, the side walls 31 extend at least in sections in a plane parallel to the longitudinal axis L and the transverse direction Q. Each side wall 31 has a first side wall edge 33 on the front side 32 of the needle body 21 and a second side wall edge 35 on the back side 34 of the needle body 21 opposite to the front side 32 in the transverse direction Q. At least in the region of the eye 30 where it has a developed clearance gauge profile 36 ( FIGS. 4 and 18 ), the two side wall edges 33 , 35 extend mainly parallel to the longitudinal axis L or are convexly curved away from the second longitudinal centre plane M2 .

The two side walls 31 defining the eye 30 are connected to each other on the side associated with the needle tip 25 by a lower transverse surface 40 and on the opposite side by an upper transverse surface 41. Thus, the gauge profile 36 is defined by the two transverse surfaces 40, 41 and the two side walls 31. Looking downward toward the eye 30, i.e., in the transverse direction Z, the transverse surfaces 40, 41 are arcuate ( FIGS. 3 and 17 ). Furthermore, the transverse surfaces 40, 41 may extend in an arcuate manner, at least in sections, in each projection plane parallel to the first longitudinal center plane M1 ( FIGS. 4 and 18 ).

A thread groove 39 is provided in the front face 32 of the needle body 21 in the tapered region 24 of the working portion 23. In the exemplary embodiment shown here, the thread groove is arranged symmetrically with respect to the first longitudinal center plane M1. The thread groove 39 has a groove portion 39a adjacent to the eye 30. On the side of the eye 30 associated with the tip 25, the groove portion 39a transitions into the eye 30. In other words, the groove portion 39a forms a lower edge 45 with the lower transverse surface 40.

Furthermore, the thread groove 39 has two thread groove openings 42, 43. In the embodiment described herein, the two end portions 39b, 39c of the thread groove 39 adjoin the groove portion 39a and each have one thread groove opening 42, 43, respectively. The thread groove 39 is arranged in the needle body 21 relative to the envelope or outer contour surface A of the working portion 23 of the sewing needle 20 and terminates at one end of the eye 30 and at two thread groove openings 42, 43 in the outer contour surface A at a distance from the eye 30. The twist groove formed by the thread groove can also be referred to as a double twist groove due to the thread groove openings 42, 43.

The outer contour surface A of the needle body 21 is specified in the working portion 23 by an enclosing contour. This contour defines the surface that the working portion 23 would have if the needle eye 30 and the thread groove 39 were not present. The outer contour surface A is only schematically depicted in Figures 2, 16 and 18.

Here, it should be noted that the term "edge" in the present version is understood not to mean a sharp, angled edge. On the contrary, for example, the edges of the lower edge 45 or the side wall edges 33, 35 are rounded or have a radius so as not to form a sharp edge on the needle body 21 that could damage the thread.

In Figures 4 and 18 , the working portion 23 of the needle body 21 is segmented along a first center plane M1. There, the thread groove 39 has a vertex line that extends along the thread groove 39's progression or thread guiding direction and forms a groove bottom 46. In the groove portion 39a, this vertex line begins at the lower edge 45 and extends along the first longitudinal center plane M1. In the region of the groove portion 39a opposite the second longitudinal center plane M2, the groove bottom 46 extends at an angle. The distance of the groove bottom 46 from the longitudinal axis L and from the second longitudinal axis M2, respectively, decreases in the region of the groove portion 39a, starting from the eye 30 or the lower edge 45, in a direction toward the longitudinal axis L of the needle tip 25.

15 to 20 , the groove bottom 46 is preferably flat along the entire groove in the lateral direction S. As a modification thereof, it can also be convexly curved, unlike what is depicted.

Adjacent to the gap gauge profile 36, each of the two side walls 31 has a side wall region 47. The two side wall regions 47 define a groove portion 39a adjacent to the lower edge 45 in the lateral direction S. According to the example, the side wall region 47 transitions without an edge or offset into the region of the side wall 31 located adjacent to the gap gauge profile 47 of the needle eye 30. The upper side wall edge 33 continues in the side wall region 47 in an edge portion 48, which approaches the second longitudinal center plane M2 as the distance from the needle tip 25 decreases. According to the example, the edge portion 48 extends in an arcuate manner. The distance of the edge portion from the second longitudinal center plane M2 is less 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 gap gauge profile 36 (Figure 8).

Adjacent to the groove portion 39a, the wire groove 39 has two end portions 39b, 39c, each of which has a wire groove opening 42, 43. According to the example, the two end portions 39b, 39c extend on different sides of the first longitudinal center plane M1, and in doing so, the first longitudinal center plane M1 can serve as a dividing surface between the two end portions 39b, 39c.

In the exemplary embodiment shown in Figures 1 to 9, the two end portions 39b, 39c are separated from one another in the region of the first longitudinal center plane M1. The protuberance 51 is preferably symmetrical relative to the first longitudinal center plane M1 and, in the exemplary embodiment, is configured as a convex protuberance. In the transition region between the two end portions 39b, 39c, the protuberance 51 is rounded and has neither edges nor offsets. Thus, during the sewing operation, the thread can slide from one end portion 39b, 39c to the other end portion 39c and/or 39b, respectively, without being damaged.

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

Looking downward toward the protuberance 51 in the transverse direction Q, the width of the protuberance decreases continuously in the lateral direction S along the longitudinal axis L away from the needle tip 25. Similarly, the height of the protuberance 51 decreases in the transverse direction Q along the longitudinal axis L away from the needle tip 25. The protuberance 51 has an apex 51a at which the protuberance 51 is at its greatest distance from the second longitudinal center plane M2. The apex 51a lies in the first longitudinal center plane M1. The distance between the apex 51a and the second longitudinal center plane M2 in the transverse direction Q is less by a difference D than the distance between the first sidewall edge 33 and the second longitudinal center plane M2 in the transverse direction Q ( FIG. 8 ). The distance between the first sidewall edge 33 is measured in the region of the opening of the needle eye 30, i.e., in the region of the gauge profile 36. The distance between the second sidewall edge 35 and the second longitudinal center plane M2 is preferably also greater than the distance between the apex 51a and the second longitudinal center plane M2 and, for example, can be the same distance as the distance between the first sidewall edge 33 and the second longitudinal center plane M2. As a result, in the transverse direction Q, large-dimensioned side walls 31 can be achieved, which provide the sewing needle 20 with good stability in the region of the needle eye 30 .

Unlike the first exemplary embodiment according to Figures 1 to 9 , the two end portions 39b, 39c in the second exemplary embodiment according to Figures 15 to 20 are not separated by a ridge 51. Instead, the groove base 46 is preferably open (patent) in the lateral direction S, so that the two end portions 39b, 39c merge directly into one another in the first longitudinal center plane M1 without offset or edge. Consequently, the two wire groove openings 42, 43 abut directly against one another in the first longitudinal center plane M1. Therefore, viewing the working portion 23 in the transverse direction A, the wire groove 39 has a profile that, beginning at the needle eye 30, initially widens along the first groove portion 39a toward the needle tip 25 in the lateral direction S. The two end portions 39b, 39c begin at the point where the edge 48 of the side wall region 47 transitions into the groove base 46. Together, the two end portions 39b, 39c share a common profile that tapers from the groove portion 39a toward the needle tip 25. Thus, the wire groove 39 has a dimension in the lateral direction S that decreases, starting at the groove portion 39a, in the direction of the needle tip 25 along the two end portions 39b, 39c. As a result, the wire groove 39 has a triangular profile at both end portions 39b, 39c, as viewed in the transverse direction Z, wherein the lateral lines of the triangle may extend in an arcuate manner. In this exemplary embodiment, the wire groove 39 has its largest dimension in the lateral direction S at the transition point between the groove portion 39a and the two end portions 39b, 39c.

The ridge 51 forms the essential difference between the two exemplary embodiments illustrated and described herein. In the second exemplary embodiment according to Figures 15 to 20, the ridge 51 between the two end portions 51 is removed and replaced by an open inner surface of the thread groove. Apart from this, the two exemplary embodiments of the sewing needle 20 are identical.

The wire trough 39 is open toward the front face 32. At two wire trough openings 42, 43, the wire trough 39 is additionally open in the lateral direction S on both sides of the first longitudinal center plane M1. In the exemplary embodiment, the wire trough 39, or at least the two end portions 39b, 39c, are arranged only on one side, as viewed relative to the second longitudinal center plane M2. Therefore, the wire trough 39 does not extend through the second longitudinal center plane M2, but it can reach the second longitudinal center plane M2.

In a modification thereof, at least the two end portions 39b, 39c can also extend through the second longitudinal center plane M2, as illustrated in a highly schematic manner in FIG. 9 by chain lines. In an extension of the last-mentioned embodiment, the entire wire duct 39 can even be located on the other side of the second longitudinal center plane M2, as viewed from the front side 32. Additionally or alternatively, the duct portion 39a can also extend through the longitudinal center plane M2.

However, in a preferred embodiment, the second longitudinal center plane M2 does not intersect the thread groove 39 at any point and at most touches it. This has the advantage that the sewing needle 20 can be manufactured in a very simple manner by forming, in particular by stamping.

The line groove 39 represents the twist groove of the sewing needle 20, which is configured so as to be symmetrical relative to the first longitudinal center plane M1 in the exemplary embodiment shown. Preferably, the sewing needle 20 as a whole is configured so as to be symmetrical relative to the first longitudinal center plane M1.

FIG3 schematically illustrates the width of the twist groove or wire groove 39 at various points in the first exemplary embodiment according to FIG1 to FIG9 . The groove portion 39a has a width B1 in the lateral direction S that is at least as great as the minimum distance between the two side walls 31 in the lateral direction S. Each of the two end portions 39b, 39c has a width B2 that is smaller than the width B1 of the groove portion 39a. The width B2 of the respective end portion 39b, 39c is measured at right angles to the wire guiding direction F. The wire guiding direction F is determined by the direction of the respective edge portion 48 adjoining the respective end portion 39b, 39c.

A gripper opening 53 is provided in the working portion 23 of the needle body 21 on the front face 32 on the side of the eye 30 opposite the thread groove 39. Therefore, in the area of the gripper opening 53, the needle body 21 has a lower thickness in the transverse direction Q than in the two adjacent areas along the longitudinal axis L. This gripper opening 53 enables the sewing machine's gripper to better grasp the needle thread running along the needle body 21 on the front face 32 and wind it around the bobbin thread. The gripper opening 53 has two bevels 54 arranged symmetrically with respect to the first longitudinal center plane M1 (Figures 3 and 5 or Figures 17 and 19). However, it is also possible to provide the bevels on only one side, or to design the opening so as to be symmetrical in another manner with respect to the longitudinal center plane M1. The sewing needle 20 can interact with the sewing machine's gripper, which, viewed in the lateral direction S, grips the thread from one or the other side. As a result, the sewing needle 20 is also suitable for use in sewing machines having two sewing needles. Due to the symmetrical configuration of the sewing needle 20 relative to the first longitudinal center plane M1, there is no risk of confusion even when using two needles in a sewing machine. In such a sewing machine, the two described sewing needles 20 can be used without the risk of confusion.

10 to 14 , the use of the sewing needle 20 in the sewing machine is explained when sewing material 60. This explanation applies to all exemplary embodiments, even though FIG. 10 to FIG. 4 shows the first exemplary embodiment of the sewing needle 20 according to FIG.

In Figure 10 , the needle 20 is positioned at a distance from the sewing material 60. The upper thread 61 extends from the last stitch in the sewing material 60 through the eye 30 of the needle 20. The sewing material 60 is moved in a first transport direction T1. This first transport direction T1 is oriented parallel to the lateral direction S of the needle 20. In doing so, the needle 20 moves downward along its longitudinal axis L toward the sewing material 60. At least until the needle tip 25 pierces the sewing material 60, the upper thread 61 remains within one of the two thread slot openings 42, 43, in this example, the first thread slot opening 42. This prevents unintended twisting of the upper thread 61.

In Figure 12, after its return stroke from the sewing material 60, the needle 20 is again in its initial position as shown in Figure 1. Now, assume that the conveying direction of the sewing material 60 is reversed. For the continued sewing process, the sewing material moves along a second conveying direction T2, which is opposite to the first conveying direction T1. During this direction reversal, the portion of the upper thread 61 extending from the needle eye 30 to the sewing material 60 moves from the first thread slot opening 42 to the second thread slot opening 43, optionally via the existing protuberance 51 (Figures 13 and 14). In doing so, if the protuberance 51 is present, the upper thread 61 slides over the convex protuberance 51, which has no edge or offset between the two end portions 39b, 39c. In doing so, twisting and displacement of the upper thread 61 is at least substantially avoided. The upper thread 61 does not move over a sharp edge or offset that is tilted at an angle that is approximately aligned with the direction of extension of the upper thread 61, which could cause the upper thread 61 to twist or untwist.

After the reversal of the transport direction is performed, the sewing material 60 is subsequently moved into the second transport direction T2, and the sewing needle 20 performs a stroke movement along its longitudinal axis L. In doing so, similar to the situation shown in Figures 10 and 11, the upper thread 61 remains in the second thread groove opening 43 as long as the sewing needle 20 has not yet pierced the sewing material 60.

According to the example, the sewing needle 20 is therefore provided for sewing in at least two opposite transport directions T1 , T2 .

The sewing needle according to the invention is preferably equipped with a displacement tip or a cutting tip.

The present invention relates to a sewing needle 20 for use in a sewing machine. The sewing needle 20 has a working portion 23 with an eye 30 and a region 24 that tapers toward a needle tip 25. The eye 30 extends through the needle body 21 of the sewing needle 20 in a transverse direction Q, perpendicular to the longitudinal axis L of the needle body 21. A twist groove is introduced into the front face 23 of the needle body 21 in a recessed manner relative to the outer contour of the needle body 21, extending from the eye 30 in the direction of the needle tip 25. The twist groove is formed by a thread groove 39 having two thread groove openings 42, 43. The twist groove is preferably symmetrical with respect to a first longitudinal center plane M1, which is generated by the longitudinal axis L and the transverse direction Q. The thread groove 39 has a groove portion 39a adjacent to the eye 30. The thread groove has two end portions 39b, 39c at a distance from the eye 30, each of which includes a thread groove opening 42, 43. In an exemplary embodiment, a convex rounded ridge 51 can separate the two end portions 39b, 39c from each other. The ridge 51 is preferably configured so as to be symmetrical with respect to the first longitudinal center plane M1.

List of reference numerals:

20 sewing needles

21 needle body

22 Needle holding part

23 Work Department

24 Gradually tapering area

25 needle tip

26 handle

30 needle eye

31 sidewall

32 Front

33 First side wall edge

34 rear side

35 Second side wall edge

36 Gage Profile

39 Wire Slot

39a Wire duct

39b First end portion

39c Second end portion

40 Lower lateral surface

41 Upper lateral surface

42 First wire slot opening

43 Second wire slot opening

45 bottom edge

46 groove bottom

47 Sidewall area

48 Edge

51 bulge

51a Vertex

53 grip opening

54 bevel

60 Sewing materials

61 Noodles

A Outer contour surface

B1 Groove width

B2 Width of the end portion

F line guidance direction

L longitudinal axis

M1 First longitudinal center plane

M2 Second longitudinal center plane

Q Horizontal direction

S lateral direction

T1 First conveying direction

T2 Second conveying direction.

Claims (16)

1. A sewing needle for a sewing machine (20). The device has a needle body (21) extending along a longitudinal axis (L), the needle body including a holding part (22) for holding the sewing needle (20) in the sewing machine, and a working part (23) including the needle tip (25) of the sewing needle (20). It has a needle eye (30) provided in the working part (23) of the needle body (21), the needle eye extending completely through the needle body (21) in the transverse direction (Q). It has a groove (39) disposed between the eye (30) and the tip (25), and terminates in the eye (30) at the lower edge (45) of the eye (30) facing the tip (25). The groove (39) has a first groove opening (42) and a second groove opening (43) at a certain distance from the eye of the needle (30). The openings are arranged on different sides of a first longitudinal center plane (M1) passing through the needle body (21), wherein the first longitudinal center plane (M1) is defined by the longitudinal axis (L) and the transverse direction (Q). 2. The sewing needle according to claim 1, The feature is that the distance between the two slot openings (42, 43) on the lateral direction (S) perpendicular to the first longitudinal center plane (M1) is greater than the width of the slot (39) along the lateral direction (S) at at least several points at the point adjacent to the eye (30). 3. The sewing needle according to claim 1 or 2, The feature is that the groove (39) has a dimension that starts from the eyelet (30) and increases in the direction of the two groove openings (42, 43) in a lateral direction (S) perpendicular to the first longitudinal center plane (M1). 4. The sewing needle according to claim 1 or 2, The feature is that the groove (39) has a groove (39a) that is directly adjacent to the eye (30). 5. The sewing needle according to claim 4, The groove (39a) is characterized on the opposite side by a sidewall region (47) that defines the sidewall of the eye (30). 6. The sewing needle according to claim 4, The groove (39a) is characterized in that the bottom (46) of the groove approaches the longitudinal axis (L) from the eye of the needle (30) along the direction of the needle tip (25). 7. The sewing needle according to claim 4, The feature is that the groove (39) has two end portions (39b, 39c) extending between a corresponding groove opening (42, 43) and the groove portion (39a). 8. The sewing needle according to claim 7, The feature is that the end portions (39b, 39c) of the groove are disposed in the region (24) of the working part (23), the region gradually tapering toward the needle tip (25). 9. The sewing needle according to claim 7 or 8, The feature is that the width (B2) of the end portion (39b, 39c) is smaller than the width (B1) of the groove portion (39a). 10. The sewing needle according to claim 7 or 8, The feature is that the protrusion (51) is disposed between the two end portions (39b, 39c) of the groove (39). 11. The sewing needle according to claim 10, The feature is that the bulge (51) transitions into the two end portions (39b, 39c) of the groove (39) without any edges. 12. The sewing needle according to claim 10, The feature is that the bulge (51) is convexly curved and has a vertex (51a) on the first longitudinal center plane (M1). 13. The sewing needle according to claim 1 or 2, The feature is that the groove (39) does not extend through the second longitudinal center plane (M2) passing through the needle body (21), the plane being oriented at a right angle relative to the first longitudinal center plane (M1). 14. The sewing needle according to claim 1 or 2, The needle eye (30) is defined on opposite sides of the first longitudinal center plane (M1) by a sidewall (31), wherein the sidewall (31) is adjacent to the outer contour surface (A) of the needle body (21) on a sidewall edge (33, 35). 15. The sewing needle according to claim 10, The needle eye (30) is defined on the opposite side of the first longitudinal center plane (M1) by a sidewall (31), wherein the sidewall (31) is adjacent to the outer contour surface (A) of the needle body (21) on a sidewall edge (33, 35), wherein the sidewall edge (33, 35) is at the maximum distance from the second longitudinal center plane (M2) which is oriented at right angles relative to the first longitudinal center plane (M1), and the distance is greater than the maximum distance of the bulge (51) relative to the second longitudinal center plane (M2). 16. Use of a sewing needle (20) according to any one of claims 1 to 15 in the sewing machine for sewing sewing material (60) fed through the sewing machine in at least two conveying directions (T).