Sewing machine needle with groove

Abstract

A sewing machine needle (1) is described, which reduces the friction between the needle body of the sewing machine needle (1) and the sewing material and which can be produced in large quantities economically. The sewing machine needle (1) comprises a needle eye (3) and at least one groove (5), wherein the upper edge (6) of the groove (5) has a spacing from the width position of the axis (12) of the needle eye (3) which is different from the spacing of the lower edge (7) of the groove (5) from the width position of the axis (12) of the needle eye (3).

Description

Technical Field

[0001] This invention relates to a sewing machine needle with a groove. Background Technology

[0002] Sewing machine needles used in industrial sewing machines have been around for decades and continue to evolve. In recent years, synthetic fiber textiles have been increasingly used, while sewing speeds have continued to rise. A problem here is the fusibility of synthetic fibers at relatively low temperatures for sewing. As sewing speeds increase, the heat entering the fabric increases due to friction with the needle. As a result, when sewing speeds are too high, the synthetic fibers undesirably melt at the needle insertion point. Therefore, in order to further increase sewing speed despite this, attempts have been made to reduce friction between the needle and the fabric.

[0003] EP2896732A1 discloses a sewing needle with a double-twist structure, comprising a recess in which two oblique grooves are arranged. The oblique grooves reduce the cross-sectional area of ​​the needle body in the region of the recess, but the oblique grooves do not cause a reduction in friction between the needle body and the sewing material because the oblique grooves are arranged in the recess at locations that do not contact the sewing material during sewing even in a sewing needle without such oblique grooves.

[0004] DE962949C1 illustrates a sewing machine needle designed to reduce frictional heat generated during sewing. For this purpose, the sewing machine needle has longitudinal grooves extending from the eye of the needle to a tapered transition area between the needle body and the shank. This reduces the contact area between the needle body and the sewn fabric, and thus also reduces friction.

[0005] EP1 391548A1 discloses a sewing machine needle having recessed grooves on two opposite sides of the needle body. These recessed grooves are intended to reduce the contact area between the needle body and the sewn fabric, thereby reducing friction.

[0006] DE3149383A1 illustrates another example of a sewing machine needle in which friction between the needle body and the sewn fabric should be reduced. The needle body is V-shaped in cross-section and has ribs separated from recesses similar to grooves. The shape of the recesses is adjusted according to the style and number of ribs. Thus, one embodiment has a star-shaped cross-section with seven ribs separated from each other by multiple small recesses. Another embodiment shows only four ribs, where each pair of ribs is spaced apart by larger recesses. The recesses are grooves that fit into the sewing machine needle in such a way that they reduce the cross-section of the needle body. This "geometry" reduces the contact area with the sewn fabric and thus reduces friction. However, the surface area of ​​the needle body should be increased. This allows the generated heat to be dissipated to the ambient air more quickly.

[0007] It has been shown that this type of sewing machine needle, known from the prior art, requires a much higher manufacturing cost and, in some cases, additional manufacturing steps compared to a conventional sewing machine needle. Summary of the Invention

[0008] Therefore, based on the prior art, the object of the present invention is to describe a sewing machine needle that reduces friction between the needle body and the sewn fabric, and does not require additional or more complex manufacturing steps.

[0009] This objective is achieved by a sewing machine needle having the following features:

[0010] -The needle body, which extends basically longitudinally.

[0011] - The eye of the needle, which completely penetrates the sewing machine needle along its height direction, wherein the height direction extends perpendicular to the longitudinal direction.

[0012] - At least one groove that reduces the extension of the needle body along the width direction perpendicular to the height direction and longitudinal direction.

[0013] -In this design, at least one groove has an upper edge and a lower edge, and the groove terminates at the upper edge and the lower edge along the height direction.

[0014] -And wherein the groove has a height at at least one location in its longitudinally extending portion, the height corresponding to at least 30% of the needle body height at the corresponding location (the groove thus has at least one cross-section in a plane unfolded by the width and height directions, in which the height of the groove corresponds to at least 30% of the height of the needle body in this cross-section), and wherein, as an additional embodiment, the upper edge spacing corresponding in the width direction to the distance between the upper edge of the groove and the axis of the eye is different from the lower edge spacing corresponding in the width direction to the distance between the lower edge of the groove and the axis of the eye. The sewing machine needle advantageously includes a clamping region, mostly a shank, which has a cross-section larger than the needle body in a plane unfolded by the width and height directions, and a transition region immediately follows the needle body longitudinally toward the eye. The cross-section of this transition region tapers longitudinally toward the eye in a plane unfolded by the width and height directions. In a needle with such a transition region, the needle body immediately follows the transition region longitudinally toward the eye. The transition region can be tapered in different ways. All shapes known to those skilled in the art in the transition region between the needle body and the clamping area are conceivable in the transition region. The transition region may, for example, have a substantially tapered orientation, wherein the tapered axis extends longitudinally. The surface of the sewing machine needle in the transition region may also have steps or radii. The manufacture of the grooves of the sewing machine needle according to the invention can be integrated into manufacturing steps known to those skilled in the art. The grooves or multiple grooves can also be manufactured simultaneously with tool movement along the height direction and / or longitudinal direction, thus achieving efficient mass production. The grooves of the sewing machine needle can be manufactured using separate manufacturing processes, such as milling, and / or using forming manufacturing processes, such as forging or extrusion. If the tool matches the geometry of the longitudinal groove, then only tool movement along the height direction and / or longitudinal direction is required, regardless of the number and position of the grooves. The grooves are generated by machining the needle blank and, in the manner described above, reduce the cross-section of the needle blank in a plane unfolded by the width and height directions. The cross-section of the needle blank can have different shapes before machining, which can be, for example, circular, elliptical, trapezoidal, or triangular. A triangular shape with rounded corners is also conceivable. Other shapes not explicitly mentioned can also be advantageous. It is also advantageous to have a sewing machine needle comprising at least two grooves, wherein in each groove, the spacing between the upper edges differs from the spacing between the lower edges. Particularly advantageous is that the grooves are arranged such that the sewing machine needle is symmetrical along the plane extending longitudinally from the eye axis.

[0015] Advantageously, the groove has uniform sections that constitute at least 10%, but preferably at least 20%, of the total longitudinal extension of the groove, and the groove has a height at any point within the uniform sections that corresponds to at least 30% of the needle body height at the corresponding point. This creates a larger area of ​​the sewing machine needle in which friction is reduced. The uniform sections do not include the inlet and outlet portions of the groove, which are the longitudinally pointing end regions of the groove. In the inlet and outlet portions, the upper and lower edges generally approach each other in the height direction until they touch. The height of the groove at a point in its longitudinal extension within the uniform sections along the height direction is advantageously the maximum height of the groove. The uniform sections of the groove are sections of the needle body, which therefore includes the uniform sections of the groove.

[0016] Further advantageously, the upper edge spacing is smaller than the lower edge spacing. Particularly advantageous is a sewing machine needle in which the upper edge spacing is smaller than the lower edge spacing, at least in uniform sections of the groove. This geometry is particularly advantageous when the tool has tool movement during at least one manufacturing step, the tool movement having a width component in the height direction from the upper edge towards the lower edge or in the width direction. The upper edge defines the groove along the positive height direction. The lower edge defines the groove along the negative height direction. The positive height direction here is the direction extending from the lower edge towards the upper edge. The negative height direction extends accordingly in the opposite direction, i.e., from the upper edge towards the lower edge. This definition of positive and negative height directions is effective for all feasible implementations according to the teachings of the invention. In a preferred embodiment, the sewing machine needle includes at least one recess and / or at least one thread groove, wherein the recess is arranged on the upper side pointing towards the positive height direction and the thread groove is preferably arranged on the lower side pointing towards the negative height direction. Cable trays can also be placed on the upper side, pointing in the positive vertical direction.

[0017] A further advantage for all implementation methods is that,

[0018] • Sewing machine needles include a recess, which is manufactured in a shape that is advantageously formed.

[0019] • And at least one groove and recess shall at least partially overlap in the longitudinal direction.

[0020] The use of recesses in sewing machine needles is well known to those skilled in the art. Each known embodiment of the recess is advantageous. "Overlapping longitudinally" means that the recess and groove extend at least partially parallel longitudinally, i.e., without being spaced apart from each other longitudinally. Particularly advantageously, the groove overlaps with the recess for at least 10% of the longitudinal length of the recess, but preferably at least 70% of the longitudinal length of the recess. The length of the recess is here the longitudinal length of the needle, along which the needle surface decreases in height in the recess region compared to the surrounding needle region. The length of the recess thus includes the entry and exit portions of the recess. The needle body of a sewing machine needle with a recess can be divided into two sections: the main needle body region and the recess region. The recess region is here a region in which the recess, along with its entry and exit portions, extends longitudinally. The main needle body region is the remaining area of ​​the needle body. The previously described uniform segments of the groove advantageously do not overlap with the recess region. The uniform region of the groove is advantageously situated entirely within the main needle body region, thus perfectly coinciding with it longitudinally. The main needle body region advantageously has a cross-section that remains constant longitudinally (cylindrical needle body) or a cross-section that tapers slightly longitudinally (conical needle body). The groove in the needle body can extend in a similarly “conical” manner, independent of the needle body shape, i.e., its shape tapers longitudinally towards the needle eye. However, the groove can also extend in a “cylindrical” manner, i.e., having a shape and position that remain constant longitudinally, independent of the rest of the needle body orientation. In this case, the lateral spacing function s(h) is the same at every location in the longitudinally extending portion of the uniform region of the groove. This results in different possible combinations, such as:

[0021] -A cylindrical needle body with cylindrical grooves.

[0022] - A cylindrical needle body with conical grooves.

[0023] - A conical needle body with cylindrical grooves.

[0024] - Or a conical needle with a conical groove.

[0025] For all embodiments of the sewing machine needle, it is advantageous that, at least at one point in the longitudinally extending portion of the groove, but preferably at every point in the longitudinally extending portion of a uniform section, the distance in the height direction between the upper edge and the highest point of the needle body is at most 35% of the needle body height, but preferably at most 25% of the needle body height. This creates a large groove, which effectively reduces the friction surface between the sewing machine needle and the sewn fabric.

[0026] Advantageously, the lateral spacing function s(h), which describes the distance in the width direction between the surface of the sewing machine needle and the axis of the eyelet in relation to the height coordinate h, monotonically, preferably strictly monotonically, decreases with increasing height for at least 90% of the height extension of the groove, but preferably throughout the entire height extension of the groove. The height extension of the groove is the extension of the groove along the height direction. In this way, side recesses (Hinterschnitt) are avoided and manufacturing is further facilitated. The lateral spacing function s(h) is also a function of the profile curve of the sewing machine needle surface in a plane unfolded by the height and width directions, which describes the lateral spacing in the width direction between the surface of the sewing machine needle and the axis of the eyelet in relation to the height coordinate h. The height coordinate h increases along the positive height direction H. Advantageously, the first derivative s′(h) of the lateral spacing function of the height coordinate is expressed with respect to the height coordinate h smaller than the upper edge. O And the height coordinate h of the lower edge U The height coordinate is negative, that is, when h U <h<h O When s′(h) < 0. Particularly advantageous is that the second derivative of the lateral spacing function s″(h) is less than the height coordinate h of the lower edge. U The height coordinate is greater than or equal to the height coordinate h of the upper edge. O The height coordinate is less than or equal to zero, that is, when h > h O Or h <h U When s″(h)≤0.

[0027] At least one groove spaced along the width from the axis of the eye of the needle at any location indicates a further positive effect. Advantageously, the distance between the groove and the axis of the eye of the needle in the width direction is greater than zero at any location of the groove. The plane unfolded by the axis and longitudinal direction of the eye of the needle does not intersect the groove in this way. It is particularly advantageous to have a needle with at least two such grooves, which are symmetrical with respect to the plane unfolded by the axis and longitudinal direction of the eye of the needle.

[0028] An advantageous implementation is achieved when the imaginary entry tangent at the upper edge of the groove forms an entry angle between 5° and 70°, but preferably between 10° and 40°, with the height direction. The entry tangent is a tangent in a plane expanded by the width and height directions, abutting the surface of the groove. The entry tangent touches the upper edge. According to the manufacturing method, rounded structures of varying sizes can be produced in the region of the upper edge of the groove. The entry tangent is not tangent to these rounded structures, in which the slope of the surface varies drastically in a plane expanded by the height and width directions. In a preferred embodiment, the entry tangent abuts the surface of the groove in a recessed area. Particularly advantageously, the imaginary tangent forms an angle of at least 5°, but preferably at least 10°, at any point on the surface of the groove in a plane expanded by the width and height directions.

[0029] A sewing machine needle may advantageously include at least one groove, which extends substantially longitudinally, following the eye of the needle along the direction of the needle body in a negative longitudinal direction, i.e., towards the eye, and is a recess in the height direction. In a preferred embodiment, the groove is arranged on the lower side of the needle in the negative height direction. The groove then "opens" in the negative height direction, i.e., it is not limited by the material of the sewing machine needle in the negative height direction. However, the groove can also be arranged on the upper side in the positive height direction. The groove then "opens" in the positive height direction. The groove is suitable for receiving the thread extending through the eye of the needle and guiding it longitudinally along the needle body. Advantageously, a groove terminates in the eye of the needle. The groove and the eye of the needle then merge longitudinally, so that no needle material is arranged between the eye of the needle and the groove in the longitudinal direction. However, the groove can also be spaced apart from the eye of the needle. The groove is a groove-shaped recess in the needle body. The groove is limited by the material of the needle on one side in the height direction and on both sides in the width direction. A sewing machine needle advantageously includes two grooves. A particularly advantageous type of sewing machine needle includes a first thread groove on its underside and a second thread groove on its upper side.

[0030] Advantageously, at least at one point in the longitudinally extending portion of the groove, but preferably at any point in the longitudinally extending portion of a uniform segment, it is effective that the surface of the sewing machine needle has such a orientation, in a plane unfolded by the height and width directions, in the region between the lower and upper edges of the groove, that this orientation is partially circular. The groove has a substantially constant radius, wherein the center point of the partial circle is preferably located outside the cross-section of the sewing machine needle in a plane unfolded in the height and width directions. The surface of the groove extends partially circularly in this cross-sectional plane, and the radius is the same at any point along the partial circle. This shape of the groove can be easily manufactured using both discrete and integral manufacturing processes. Further advantageously, the surface of the sewing machine needle, in the region between the lower and upper edges of the groove, has a direction in a plane unfolded in the height and width directions that consists of the partial circle and a straight line immediately following it. This straight line preferably connects tangentially to the partial circle.

[0031] A further advantage of this sewing machine needle is that, at least at one point in the longitudinally extending portion of the groove, but preferably at any point in the longitudinally extending portion of a uniform segment, the groove height corresponding to the distance along the height direction between the upper and lower edges is 60% to 170% of the maximum value of the lateral spacing function s(h), but preferably 75% to 160% of the maximum value of the lateral spacing function s(h). This selection range has proven advantageous for conventionally sized sewing machine needles because they enable an easy manufacturing process and simultaneously achieve a sewing machine needle that generates very little friction with the textile during sewing. Advantageously, a sewing machine needle is provided in which, at least at one point in the longitudinally extending portion of the recessed region, but preferably at least 20% of the longitudinally extending portion of the recessed region, the groove height corresponding to the distance along the height direction between the upper and lower edges is 25% to 150% of the maximum value of the lateral spacing function s(h), but preferably 35% to 105% of the maximum value of the lateral spacing function s(h). Particularly advantageous is a sewing machine needle in which, at least at 20% of the longitudinally extending portion of the recessed region, the groove height corresponding to the distance along the height direction between the upper and lower edges is 35% to 60% of the maximum value of the lateral spacing function s(h).

[0032] A further advantage of this sewing machine needle is that, at least at a point along the longitudinal extension of the groove, but preferably at any point along the longitudinal extension of a uniform segment, the upper edge spacing O is 10% to 60%, but preferably 25% to 45%, of the maximum value of the lateral spacing function s(h). The upper edge spacing O corresponds to the lateral spacing function at the height coordinate h of the upper edge. O The value at the location. Therefore, O = s(h) OThe selected range has proven advantageous for conventionally sized sewing machine needles because they achieve the largest possible groove, thus reducing friction and allowing for easy manufacturing, while also ensuring sufficient stability of the sewing machine needle. It is advantageous for a sewing machine needle in which, at least at one point in the longitudinal extension of the recessed region, but preferably at 20% of the longitudinal extension of the recessed region, the upper edge spacing O is 10% to 75% of the maximum value of the lateral spacing function s(h), but preferably 35% to 65% of the maximum value of the lateral spacing function s(h).

[0033] A further advantage of this sewing machine needle is that, at least at one point in the longitudinal extension of the groove along the longitudinal direction, but preferably at any point in the longitudinal extension of a uniform segment, the lower edge spacing U is 50% to 100% of the maximum value of the lateral spacing function s(h), but preferably 70% to 95% of the maximum value of the lateral spacing function s(h). The lower edge spacing U corresponds to the lateral spacing function at the height coordinate h of the lower edge. U The value at the location. Therefore, U = s(h) U The selected range has proven advantageous for conventionally sized sewing machine needles because they achieve the largest possible groove, thus reducing friction and allowing for easy manufacturing, while also ensuring sufficient needle stability. It is advantageous to have a sewing machine needle in which, at any point in the longitudinal extension of the recessed region, the lower edge spacing U is 50% to 100% of the maximum value of the lateral spacing function s(h), but preferably 70% to 95% of the maximum value of the lateral spacing function s(h).

[0034] A method for manufacturing a sewing machine needle, the sewing machine needle having a needle body extending substantially longitudinally, and the sewing machine needle having an eye penetrating the sewing machine needle in a height direction perpendicular to the longitudinal extension, the method achieving the object of the invention by means of:

[0035] - At least one groove defined by the upper and lower edges along the height direction, manufactured by tool movement that travels only along the height direction and / or longitudinally.

[0036] -And wherein, the upper edge spacing, which corresponds to the distance between the upper edge of the groove and the axis of the eye in the width direction, is different from the lower edge spacing, which corresponds to the distance between the lower edge of the groove and the axis of the eye in the width direction.

[0037] By restricting tool movement to two or even only one direction of motion, particularly efficient manufacturing is achieved. Sewing machine needles can therefore be mass-produced in this manner. This method is particularly advantageous for sewing machine needles in which the groove has a height at least 30% of the needle body height at the corresponding location at at least one location in its longitudinally extending portion.

[0038] One method offers a further advantage, in which at least one groove is preferably manufactured separately by milling. The groove can be manufactured by movement along the height and longitudinal directions when the milling cutter has a profile corresponding to the groove's contour. Additional movement along the width direction is not necessary. This approach can also be advantageously used in conjunction with other separate manufacturing processes, such as grinding or etching.

[0039] One method offers a further advantage, in which at least one groove is preferably formed by extrusion. When the extrusion tool consists of an upper die and a lower die that reflect the contour of at least one groove or a plurality of grooves, the groove can be formed by tool movement that travels only in the height direction. The groove can therefore be machined into a sewing machine needle particularly easily and efficiently. However, the groove can also be formed using an extrusion tool comprising more than two tool parts, such as an extrusion tool comprising three, four, or five tool parts. Attached Figure Description

[0040] Figure 1 A sewing machine needle (1) with a groove (5) is shown;

[0041] Figure 2 Shown in a view rotated 180° around the needle axis Figure 1 The same sewing machine needle (1);

[0042] Figure 3 A side view of a sewing machine needle (1) with a groove (5) is shown;

[0043] Figure 4 It is shown in a plane expanded by the width direction (B) and the height direction (H). Figure 3 The cross section AA of the sewing machine needle (1);

[0044] Figure 5 It shows Figure 4 The same profile and the direction of the lateral spacing function s(h);

[0045] Figure 6 It is shown in a plane expanded by the height direction (H) and the longitudinal direction (L). Figure 3 and Figure 4 The cross-section BB of the sewing machine needle (1);

[0046] Figure 7 A cross-section of the sewing machine needle (1) at the eye of the needle (3) is shown;

[0047] Figure 8 Various variations of the needle blank (8) and the reduction of the cross-section through the groove (5) and the slot (4) are shown;

[0048] Figure 9 A cross-section of a sewing machine needle (1) and a textile sewing fabric (29) with an insertion hole (28) is shown;

[0049] Figure 10a A first variant of the orientation of the lateral spacing function s(h) in the region of the groove (5) is shown;

[0050] Figure 10b A second variation of the orientation of the lateral spacing function s(h) in the region of the groove (5) is shown;

[0051] Figure 10c A third variation of the orientation of the lateral spacing function s(h) in the region of the groove (5) is shown;

[0052] Figure 10d A fourth variation of the orientation of the lateral spacing function s(h) in the region of the groove (5) is shown. Detailed Implementation

[0053] Figure 1 The sewing machine needle 1 with a groove (5) is shown in the spatial diagram (the second groove 5 is obscured in this diagram). The sewing machine needle 1 includes a clamping region 18, a transition region 19, a needle body region 23, a main needle body region 22, a uniform section 37, a recess 16, and a needle eye 3. The axis 12 of the needle eye 3 extends along the height direction H and is centrally located between the two sidewalls 9 of the needle eye 3 along the width direction B. In this embodiment, the uniform section 37 corresponds to the main needle body region 22, and the two regions therefore completely overlap. In other embodiments according to the teachings of the invention, it may be advantageous for the main needle body region 22 and the uniform section 37 to only partially overlap. The uniform section here does not overlap with the recessed region 24.

[0054] Figure 2 Shown in a view rotated 180° around the longitudinal axis 17 Figure 1 The sewing machine needle 1. The thread groove 4 extends on the underside of the sewing machine needle 1 in the negative height direction H, and extends longitudinally L from the needle eye 3 to the transition area 19. The thread groove 4 thus overlaps with the needle body area 23 and the transition area 19 longitudinally L.

[0055] Figure 3A side view of a sewing machine needle 1 is shown, including a clamping region 18, a needle body region 23, and a tapering region 20. Advantageously, in all embodiments, a needle shank 25 is arranged in the clamping region 18. The clamping region 18, in all embodiments, is suitable for being housed in the sewing machine and driven longitudinally for sewing motion. The needle body region 23 is a region in which the needle body 2 extends longitudinally. The needle body region includes a main needle body region 22 and a recessed region 24, wherein the main needle body region 22 is arranged longitudinally L before the recessed region 24 towards the eye 3. The recessed region 24 is a region in which a recess 16 extends longitudinally. The needle body 2 has a constant cross-section along the longitudinal direction L in the main needle body region 22. This is referred to by those skilled in the art as a cylindrical needle body orientation. Equally advantageous in all embodiments of the invention is that the cross-section of the needle body 2 decreases longitudinally L towards the eye 3 in the main needle body region 22. This is referred to by those skilled in the art as a tapered needle body orientation. The needle body region 23 has a smaller cross-section than the clamping region 18. A tapered transition region 19 is arranged between the clamping region 18 and the needle body region 23, or between the main needle body region 22, balancing this difference in cross-section between the clamping region 18 and the needle body region 23. A tapering region 20 connects to the needle body region 23 in a direction along the longitudinal direction L away from the clamping region 18. The cross-section of the needle monotonically decreases in this region and ends at the needle tip 21. A groove 5 is arranged in the needle body region 23, which also partially overlaps with the transition region 19 along the longitudinal direction L. The groove includes a uniform region 37 that completely coincides with the main needle body region 22. The uniform region 37 is defined along the longitudinal direction L at the same location as the main needle body region 22. However, in other embodiments according to the teachings of the invention, the boundary of the uniform region 37 may differ from the boundary of the main needle body region 22. The groove 5 is defined along its height by an upper edge 6 and a lower edge 7. It is also advantageous for all embodiments that the groove 5 is entirely within the needle body region 23, and thus both the beginning and end of the groove 5 along the longitudinal direction L are within the needle body region 23. The groove 5 overlaps with the recess 16 along the longitudinal direction by an overlap length 26. The groove is therefore also partially within the recess region 24. In this example, the overlap length 26 corresponds to 90% of the recess length 27 along the longitudinal direction L. However, it is advantageous for all embodiments that the overlap length 26 is at least 10% of the recess length, preferably at least 70% of the recess length 27. It is equally advantageous for the sewing machine needle 1 according to the invention that the groove 5 does not overlap with the recess 16 along the longitudinal direction L.

[0056] Figure 4 It shows in Figure 3The section AA of the sewing machine needle 1 is shown at the location depicted. The section, along the longitudinal direction L, lies directly before the beginning of the transition region 19 at the end of the needle body region 23, thus showing the cross-section of the needle body 2, which is furthest from the eye 3 along the longitudinal direction L. The needle body 2 has two grooves 5 and a thread groove 4. The grooves 5 reduce the cross-section of the needle body 2 and have a concave shape in the section plane. Behind the section plane, the needle shank 25 is shown, which has a larger cross-section than the needle body 2. The upper edge 6 and lower edge 7 are cut by the section plane and define the grooves 5 both upwards and downwards along the height direction H. The width position of the axis 12 of the eye 3 is also shown. The upper edge 6 is spaced from the axis 12 of the eye 3 along the width direction B by an upper edge spacing O. The lower edge 7 is spaced from the axis 12 of the eye 3 along the width direction B by a lower edge spacing U. The upper edge spacing O and the lower edge spacing U are not the same size: in this case, the upper edge spacing O is smaller than the lower edge spacing U. In all embodiments of the invention, the groove height 11 corresponding to the distance between the upper edge 6 and the lower edge 7 in the height direction H is more than 30% of the needle body height 10 of the needle body 2 along the height direction H. The positions of the surface 13 of the sewing machine needle 5 and the axis 12 of the eye 3 are spaced apart by a lateral distance s in the width direction, wherein the lateral distance s can be described by a lateral distance function s(h), which is related to the height coordinate h in the height direction, i.e., s = f(h) = s(h). In the end region of the groove 5, the entry tangent 14, which is tangent to the curve of the lateral distance function s(h) at the upper edge 6, forms an entry angle 15 greater than 5° relative to the height direction H. However, for all embodiments of the sewing machine needle 1, the range of choices for the entry angle 15 mentioned in the preceding paragraph is advantageous.

[0057] Figure 5 It shows Figure 4 The same cross-section is shown again, and the lateral spacing function s(h) is shown once more. The upper edge spacing O is at the height coordinate h of the upper edge 6. O The value of the corresponding lateral spacing function s(h), i.e., O = s(h) O The lower edge spacing U is located at the height coordinate h of the lower edge 7. U The value of the corresponding lateral spacing function s(h), i.e., U = s(h) U In this embodiment, the lateral spacing s decreases strictly monotonically with increasing height coordinates in the height extension region of the groove 5. Therefore, applicable over the entire groove height 11, the derivative of the lateral spacing function s(h) is less than 0 (for h). O h>h U(s′(h)<0). This curve trend is advantageous for all embodiments. Also advantageous for all variations is that the lateral spacing decreases monotonically with increasing height, i.e., the derivative of the lateral spacing function s(h) is less than or equal to 0 (for h). O h>h U , s′(h)≤0). For the height coordinate h less than the lower edge 7. U The height coordinates and the height coordinates h for the upper edge greater than 6. O The second derivative of the lateral spacing function, s″(h), is less than zero when h > h. O Or h <h U When s″(h)<0).

[0058] Figure 6 The diagram shows a cross-section BB of the sewing machine needle 1 in a plane developed by the axis 12 of the eye 3 and the longitudinal direction L. The position of cross-section BB is also... Figure 4 As shown in the diagram. The eyelet 3 is arranged in the tapered region 20 of the sewing machine needle 1, and the axis 12 of the eyelet 3 is centrally located in the eyelet 3 along the longitudinal direction L. From the observer's perspective, behind the cross-sectional plane, the eyelet 3 is defined by the sidewall 9 in the width direction B. On the underside of the sewing machine needle 1, a groove 4 connects to the eyelet 3. The eyelet 3 and the groove 4 are not spaced apart from each other along the longitudinal direction L, but rather merged together. The groove 4 extends through the entire needle body region 23 and terminates within the transition region 19. The groove 4 is a recess in the needle body 2 of the sewing machine needle 1, which is adapted to accommodate the sewing thread during sewing. The groove 4 has been known to those skilled in the art over many years in various embodiments. The teachings of the present invention allow for advantageous combinations with any known pattern and shape of the groove 4.

[0059] Figure 7 The diagram shows the position of the sewing machine needle 1 at the eye 3 in a plane formed by the height direction H and the width direction B. Figure 6 The same section CC. The location of section CC is... Figure 6 The eyelet 3 is defined on both sides along the width direction B by a sidewall 9. The axis 12 of the eyelet 3 extends through the eyelet 3 precisely in the width direction B. In all other embodiments of the invention, the axis 12 of the eyelet 3 also has this position along the width direction B. Furthermore, a thread groove 4 is shown on the underside of the sewing machine needle 1, which is directly connected to the eyelet 3.

[0060] Figure 8The possible shapes of the needle blank 8 and possible arrangements of the grooves 5 for any shape are shown. The cross-section of the needle blank 8 can be circular 32, elliptical 33, trapezoidal 34, triangular 30, or triangular 31 with rounded corners. However, the needle blank can also have a cross-sectional shape 35 consisting of two partial circles and two inclined straight lines, wherein the partial circles have different radii and are connected to each other by the two inclined straight lines. Furthermore, in Figure 8 The second column shows how the groove 5 according to the invention reduces the cross-section of the needle blank 8 of this shape. Figure 9 The third column shows how the groove 4 reduces the cross-section of the needle blank 8 of this shape. The teachings of the invention can also be advantageously applied to needle blanks 8 having all the other cross-sectional shapes already known for sewing machine needles 1.

[0061] Figure 9 A cross-section of the sewing machine needle 1 and the sewing fabric 29 at the location of the insertion hole 28 in the textile sewing fabric 29 is shown. The sewing fabric 29 does not have contact with the sewing machine needle 1 in the region of the groove 5. Therefore, friction is also absent in this region, which generally leads to reduced friction between the sewing machine needle 1 and the sewing fabric 29. The insertion hole 28 is in... Figure 9 Ideally, it is shown as a circle. Depending on the textile and mechanical properties of the sewing fabric 29 and the shape of the needle cross-section, other shapes of the insertion hole 28 can also be produced. However, what they have in common is that the sewing fabric 29 does not have contact with the sewing machine needle 1 in the area of ​​the groove 5.

[0062] Figures 10a to 10d Four alternative cross-sectional shapes for the groove 5 in the sewing machine needle 1, or the corresponding orientation of the lateral spacing function s(h), are shown. These alternative cross-sectional shapes can be advantageously combined with all feasible embodiments of the invention. Figure 10a In this embodiment, the lateral spacing function s(h) between the upper edge 6 and the lower edge 7 of the groove 5 consists of two straight lines with different slopes, wherein the slopes are not equal to 0. Figure 10b In one embodiment, the lateral spacing function s(h) between the upper edge 6 and the lower edge 7 of the groove 5 consists of five straight lines, wherein adjacent lines have different slopes, and each slope is not equal to 0. Figure 10c In one embodiment, the lateral spacing function s(h) between the upper edge 6 and the lower edge 7 of the groove 5 is composed of three partial circles. Figure 10dAn embodiment with a lateral spacing function s(h) is shown, which consists of a partial circle and a straight line connecting the partial circle along the positive height direction H. The figure shows the transition point 36 between the straight line and the partial circle: the partial circle begins at the lower edge 7 along the positive height direction H and terminates at the transition point 36. At this transition point 36, a straight line is tangentially connected to the partial circle, continuing its course in the positive height direction H and terminating at the upper edge 6.

[0063] List of reference numerals in the attached diagram:

[0064] 1 Sewing machine needle

[0065] 2 needle body

[0066] 3 pinholes

[0067] 4 cable trays

[0068] 5 grooves

[0069] 6. Upper edge of groove (5)

[0070] 7. Lower edge of groove (5)

[0071] 8 needle blanks

[0072] 9. Sidewall of the needle eye (3)

[0073] 10 needle body height

[0074] 11. Height of groove (5)

[0075] 12. The axis of the needle eye (3)

[0076] 13 Surface of sewing machine needle (1)

[0077] 14 Entering the tangent

[0078] 15 Entry Angle

[0079] 16 recess

[0080] 17. Vertical axis

[0081] 18 Clamping Area

[0082] 19 Transition Zone

[0083] 20 Gradual contraction zone

[0084] 21 needle tip

[0085] 22 Main needle body

[0086] 23 Needle body area

[0087] 24 concave area

[0088] 25 needle handle

[0089] 26 Coincidence Length

[0090] 27. Length of the recess (16)

[0091] 28. Penetration hole

[0092] 29. Sewing materials

[0093] 30 Needle blanks with a triangular cross-section 8

[0094] 31. Needle blank with a triangular cross-section and rounded corners.

[0095] 32. Needle blank with a circular cross-section 8

[0096] 33. Needle blank with an elliptical cross-section 8

[0097] 34. Needle blank with a trapezoidal cross-section 8

[0098] 35. A needle blank having a cross-sectional shape consisting of two partial circles and two straight lines.

[0099] 36 Transition Points

[0100] 37 Uniform sections of groove (5)

[0101] B Width direction

[0102] L longitudinal

[0103] H (height direction)

[0104] h height coordinates

[0105] s Lateral spacing

[0106] s(h) is the lateral spacing function related to the height coordinate (h).

[0107] O Upper edge spacing

[0108] U-shaped lower edge spacing

[0109] h O The height coordinate at the height of the upper edge 6

[0110] h U The height coordinates at the height of the lower edge 7.

Claims

1. A sewing machine needle (1), which has the following characteristics: • The needle body (2), which extends substantially along the longitudinal direction (L), • The eye of the needle (3) completely penetrates the sewing machine needle (1) along the height direction (H), wherein, The height direction (H) extends perpendicular to the longitudinal direction (L). • A recessed region (24) extending longitudinally (L) of the needle body (2), wherein the recessed region (24) includes a recess (16). • At least one groove (5) formed in the needle body, wherein the at least one groove is configured to reduce friction between the needle body (2) and the sewing material, wherein the at least one groove (5) extends longitudinally (L) beyond the recessed area (24) and reduces the extension of the needle body (2) in the width direction (B) perpendicular to the height direction (H) and the longitudinal direction (L). • In this groove (5), at least one groove has an upper edge (6) and a lower edge (7), and the groove (5) terminates at the upper edge and the lower edge along the height direction (H). Furthermore, the groove (5) has a height (11) at at least one location in its longitudinally extending portion along the longitudinal direction (L), the height corresponding to at least 30% of the needle height (10) of the needle body (2) at the corresponding location. Its features are, • The upper edge spacing (O) corresponds to the distance in the width direction (B) between the upper edge (6) of the groove (5) and the axis (12) of the eye (3) in the width direction. This upper edge spacing (O) is different from the spacing in the width direction (B) between the upper edge (6) of the groove (5) and the axis (12) of the eye (3). • Lower edge spacing (U), which corresponds to the spacing in the width direction (B) between the lower edge (7) of the groove (5) and the axis (12) of the eye (3) in the width direction (B).

2. The sewing machine needle (1) according to claim 1, characterized in that, The groove (5) has uniform segments (37) that constitute at least 10% of the total extension of the groove (5) along the longitudinal direction (L). Furthermore, the groove (5) has a height (11) at any location in the uniform section (37), which corresponds to at least 30% of the needle height (10) of the needle body (2) at the corresponding location.

3. The sewing machine needle (1) according to claim 2, characterized in that, The uniform segments constitute at least 20% of the total extension of the groove (5) along the longitudinal direction (L).

4. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that, The upper edge spacing (O) is smaller than the lower edge spacing (U).

5. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that, The sewing machine needle (1) includes a recess (16) which is advantageously formed. Furthermore, the at least one groove (5) and the recess (16) at least partially overlap along the longitudinal direction (L).

6. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that, • It is effective at least at one point in the longitudinal extension of the groove (5) along the longitudinal direction (L). The distance between the highest point of the upper edge (6) and the needle body (2) in the height direction (H) is at most 35% of the needle body height (10).

7. The sewing machine needle (1) according to claim 6, characterized in that, The distance between the upper edge (6) and the highest point of the needle body (2) in the height direction (H) is at most 25% of the needle body height (10).

8. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that, The lateral spacing function (s(h)) describes the spacing in the width direction (B) between the surface (13) of the sewing machine needle (1) and the axis (12) of the eye (3) based on the height coordinate (h), and the lateral spacing function decreases monotonically with increasing height for at least 90% of the height extension of the groove (5).

9. The sewing machine needle (1) according to claim 8, characterized in that, The lateral spacing function decreases strictly monotonically with increasing height throughout the entire height extension of the groove (5).

10. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that, The at least one groove (5) is spaced apart from the position of the axis (12) of the eye (3) in the width direction (B) at any location.

11. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that, The entry tangent (14) of the groove (5) at the upper edge (6) forms an entry angle (15) between 5° and 70° relative to the height direction (H).

12. The sewing machine needle (1) according to claim 11, characterized in that, The entry tangent (14) of the groove (5) at the upper edge (6) forms an entry angle (15) between 10° and 40° relative to the height direction (H).

13. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that... At least one groove (4) extends substantially in the longitudinal direction (L), the groove follows the eyelet (3) in the negative longitudinal direction (L), and the groove is a recess in the height direction (H).

14. The sewing machine needle (1) according to any one of claims 1 to 3, characterized in that, • It is effective at least at one point in the longitudinal extension (L) of the groove (5), The surface (13) of the sewing machine needle (1) has a partially circular orientation in the region between the lower edge (7) and the upper edge (6) in a plane unfolded by the height direction (H) and the width direction (B), with a substantially constant radius. • The center point of a portion of the circle lies outside the cross-section of the sewing machine needle (1) in a plane unfolded by the height direction (H) and the width direction (B).

15. The sewing machine needle (1) according to claim 8, characterized in that, • It is effective at least at one point in the longitudinal extension of the groove (5) along the longitudinal direction (L). The groove height (11) corresponds to the distance between the upper edge (6) and the lower edge (7) along the height direction (H), and the groove height is 60% to 170% of the maximum value of the lateral spacing function (s(h)).

16. The sewing machine needle (1) according to claim 15, characterized in that, The groove height is 75% to 160% of the maximum value of the lateral spacing function (s(h)).

17. The sewing machine needle (1) according to claim 8, characterized in that, • It is effective at least at one point in the longitudinal extension of the groove (5) along the longitudinal direction (L). • The upper edge spacing (O) is 10% to 60% of the maximum value of the lateral spacing function (s(h)).

18. The sewing machine needle (1) according to claim 17, characterized in that, The upper edge spacing (O) is 25% to 45% of the maximum value of the lateral spacing function (s(h)).

19. The sewing machine needle (1) according to claim 8, characterized in that, • It is effective at least at one point in the longitudinal extension of the groove (5) along the longitudinal direction (L). • The lower edge spacing (U) is 50% to 100% of the maximum value of the lateral spacing function (s(h)).

20. The sewing machine needle (1) according to claim 19, characterized in that, The lower edge spacing (U) is 70% to 95% of the maximum value of the lateral spacing function (s(h)).

21. A method for manufacturing a sewing machine needle (1), The sewing machine needle has a needle body that extends substantially longitudinally (L). Furthermore, the sewing machine needle has an eye (3) that extends through the sewing machine needle (1) along a height direction (H) perpendicular to the longitudinal direction (L). Its features are, • At least one groove (5) defined by the upper edge (6) and the lower edge (7) along the height direction (H) is manufactured by tool movement that travels only along the height direction (H) and / or the longitudinal direction (L). Furthermore, the upper edge spacing (O) corresponds to the distance in the width direction (B) between the upper edge (6) of the groove (5) and the axis (12) of the eye (3), which is different from the lower edge spacing (U), which corresponds to the distance in the width direction (B) between the lower edge (7) of the groove (5) and the axis (12) of the eye (3). The sewing machine needle (1) has a recessed region (24) extending longitudinally (L) of the needle body (2), wherein the recessed region (24) includes a recess (16); wherein at least one groove (5) is formed in the needle body and is configured to reduce friction between the needle body (2) and the sewn material, wherein the at least one groove (5) extends longitudinally (L) beyond the recessed region (24).

22. The method for manufacturing a sewing machine needle according to claim 21, characterized in that, The at least one groove (5) is manufactured separately by milling or formed by extrusion.

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