Textile tool and method for producing the textile tool

Abstract

The present invention relates to a textile tool (1) with a hook for use in textile machines. In order for the textile tool (1) to be suitable for use in high-speed textile machines and for processing difficult-to-process yarns, while simultaneously offering a long service life and cost-effective manufacturing, the cross-sectional area (X(s)) of the hook (3) increases along a linear coordinate (s) starting from the hook tip (5) and decreases again after reaching a maximum cross-sectional area (Xmax).

Description

[0001] The present invention relates to a textile tool with a hook for use in textile machines, such as knitting needles for knitting machines or warp knitting needles for warp knitting machines. Such textile tools with hooks have been known for well over 100 years in a wide variety of embodiments and using a wide variety of manufacturing processes. For example, knitting needles, such as those from CH398860A, are known in which the hook is formed by "cutting," i.e., by separating manufacturing processes. Similarly, lace needles, for example from US2436371, are also known in which the hook is formed by punching from a strip of sheet metal. However, the present invention relates to a textile tool with a hook in which the hook is typically formed by forming. It has been shown that a formed hook has better mechanical properties than a hook that is manufactured by machining or casting.Furthermore, the hook can be manufactured particularly cheaply by forming.

[0002] A corresponding textile tool and the associated manufacturing process are shown, for example, in DE3900162C1. The textile tool is produced by forming a blank, whereby the hook of the textile tool is formed from a substantially straight section of the blank by forging.

[0003] Increased operating speeds of textile machines and the use of difficult-to-process yarns, which place particular stress on the textile tools during operation, such as highly abrasive yarns or yarns with hard spots, have led to higher demands on the load-bearing capacity of the hooks of these tools in recent years. To address this, EP3617357A2 discloses the use of a "transition section" of the hook with increased material thickness to prevent undesired bending of the knitting needle and thus an expansion of the catch area (or hook interior). The increased material thickness therefore stiffens the hook. This publication does not provide any information on the cross-sectional area of ​​the hook.Since the contour of the hook cross-section can typically change along the centerline of textile tools, increasing the material thickness, even with a constant or reduced cross-sectional area, is only possible by modifying the contour. It has been shown that when using textile tools of the type described above, irregularities due to expanded loops in the finished textile can occur, particularly in the production of very fine textiles. It has also been shown that stiffening the hook can lead to premature hook failure in some applications.

[0004] The object of the present invention is therefore to provide a textile tool with a hook and an associated method for manufacturing the textile tool, wherein the textile tool is suitable for use in high-speed textile machines and for processing difficult-to-process yarns, while at the same time offering a long service life and cost-effective manufacturability.

[0005] The problem is solved by a textile tool according to claim 1 and a method for manufacturing the textile tool according to claim 8. The textile tool according to the invention, which is suitable for use in textile machines, has a shank and a hook, the shank extending substantially in a longitudinal direction. The hook connects to the shank longitudinally towards a front end of the textile tool and terminates with a hook point. The hook is formed by reshaping an initially straight blank section adjoining the shank and forms a hook area that extends longitudinally from the hook point to the front end of the textile tool. To solve the problem of the invention, the cross-sectional area X(s) of the hook increases along a linear coordinate s starting from the hook point and decreases again after reaching a maximum cross-sectional area Xmax.The line coordinate runs along a center line extending through the middle of the textile tool. The cross-sectional area of ​​the hook at a specific line coordinate is the area of ​​the hook's cross-section in a section plane that extends perpendicular to the center line at the location of the line coordinate. This means that the normal vector of the section plane is tangential to the center line at the location of the line coordinate. The cross-sectional area changes along the center line and is accordingly described as a function X(s) that depends on the line coordinate. According to the above definition, the hook lies entirely within the hook area. For the purposes of this patent application, all cross-sectional areas of the textile tool that lie outside the hook area are not considered cross-sectional areas of the hook.This means that the cross-sectional area X(s) of the hook decreases again within the hook area after reaching the maximum cross-sectional area Xmax. This results in a reduced cross-sectional area in the region between the maximum cross-sectional area and the shank of the textile tool. This measure allows the textile tool according to the invention to process even difficult-to-work yarns (e.g., yarns with knots, yarns with irregularities, or multifilament yarns) very effectively. The combination of the maximum cross-sectional area in the bending region with a subsequent decrease in cross-sectional area towards the shank is also advantageous because it achieves high stability in the bending region while simultaneously providing more space in the hook opening for processing yarns with increased space requirements, such as multifilament yarns.

[0006] Further advantages arise when the maximum cross-sectional area Xmax is 10% to 100%, but preferably 15% to 50%, larger than a reduced cross-sectional area Xred of the hook, which is formed in the hook area extending from the maximum cross-sectional area towards the shank. Such a significant reduction in cross-section towards the shank can considerably increase the hook's service life because, due to its significantly lower stiffness, it is able to deform elastically in the event of irregularities in the yarn (for example, hard spots) and thus adapt to these irregularities. The frequency of hook breakage can therefore be reduced, even on particularly high-speed textile machines.

[0007] It is particularly advantageous if the maximum cross-sectional area X max is 1% to 100%, but preferably 10% to 25%, larger than the cross-sectional area in a hook tip section located directly before the hook bend, extending from the hook tip towards the shank. Advantageously, the cross-sectional area at this point is the largest within the hook tip section. The hook bend is the area of ​​the hook where the centerline is curved. It has been shown that within the aforementioned selection range, a good hook service life is achieved even when processing abrasive yarns. At the same time, the hook in the aforementioned selection range still exhibits sufficiently low stiffness to adapt to irregularities in the yarn through elastic deformation.

[0008] Further advantages arise when the hook's cross-section has a substantially round, oval, square, rectangular, trapezoidal, triangular, and / or polygonal contour. The hook's cross-section can also have other different contours. Particularly advantageous are substantially oval and / or rectangular cross-sections that have a greater height in a cross-sectional vertical direction, perpendicular to the centerline and perpendicular to a horizontal direction, than their width in the horizontal direction. The horizontal direction is the direction in which the textile tools are arranged side by side in a textile machine. With such a contour, the hook has very advantageous elastic properties that facilitate the processing of yarns with hard spots. If the cross-sectional contour has edges, these edges can be rounded to prevent, for example, damage to the yarn from sharp edges during operation.For example, in the case of a rectangular or trapezoidal cross-section, the four edges of the contour can be rounded. Even with rounded edges, such a contour is still considered a rectangular or trapezoidal contour within the meaning of the present patent application. The contour of the cross-section can change along the line coordinate in the hook area. The hook can therefore have several cross-sections with differently shaped contours. Combinations of the aforementioned contours are thus also possible.

[0009] It is particularly advantageous if the hook's cross-section has a substantially rectangular, square, or teardrop-shaped contour in the hook tip section and a substantially oval or round contour in the area of ​​the hook's bend. A square or rectangular contour in the hook tip section can surprisingly significantly reduce wear in this area of ​​the hook. This considerably extends the service life of the textile tool. A teardrop-shaped contour in the hook tip section is especially beneficial for textile tools with a slider. The teardrop-shaped contour provides better guidance for the slider when the hook closes. This allows the textile tool to be operated at higher speeds without excessive wear. In this way, both productivity and the service life of the textile tool can be increased.In the area of ​​its bend, the cross-section of the hook preferably has a round or oval contour. In combination with a square, rectangular, or teardrop-shaped contour in the hook tip section, the service life of the textile tool can surprisingly be improved significantly.

[0010] A particularly long service life of the textile tool when processing abrasive yarns can be achieved by ensuring that the maximum cross-sectional area Xmax is located in the hook bend. The hook bend is the section of the hook where the center line is curved. When processing abrasive yarns, particularly high wear occurs in the area of ​​the hook bend. Due to the large cross-sectional area, the hook in this region will not fail even if an abrasive yarn has already worn away a significant amount of the hook material during operation.

[0011] Further advantages arise when the hook's cross-section, with its maximum cross-sectional area Xmax, has a substantially oval contour. This oval contour reduces material removal when processing abrasive yarns. Combined with the increased cross-sectional area, this can extend the service life of the textile tool.

[0012] The features of the textile tool according to the invention described above can be combined with each other in all possible combinations in different embodiments of the teaching according to the invention.

[0013] The textile tool according to the invention can advantageously be manufactured from a blank state of the textile tool in a process with the following described process steps. First, a straight blank section of the textile tool adjoining the shaft is processed such that the cross-sectional area Y(s) of the blank section increases along the line coordinate s starting from the end of the blank section and decreases again within the blank section starting from a maximum cross-sectional area Ymax of the blank section. Subsequently, the hook is formed by shaping the straight blank section. After the hook has been formed, the end of the blank section forms the hook point.Due to the preceding processing of the straight blank section with the described change in the cross-sectional area Y(s), the cross-sectional area X(s) of the hook can be determined simply by forming the hook from the blank section. This area increases along the line coordinate s from the hook tip and decreases again after reaching the maximum cross-sectional area Xmax of the hook. However, the cross-sectional area can change slightly during the forming process. Therefore, the shape of the cross-sectional area Y(s) of the blank section along the line coordinate s is not necessarily the same as the shape of the cross-sectional area X(s) of the formed hook. The straight blank section has a substantially straight centerline. During the forming process, the centerline acquires a curved section in the hook area.

[0014] Further advantages arise when the cross-sectional areas Y(s) of the straight blank section are processed by forming with at least one forming tool, by machining processes, and / or by subtractive manufacturing processes. The desired shape of the cross-sectional areas Y(s) of the straight blank section can be produced particularly well and cost-effectively in this way. Furthermore, forming with at least one forming tool allows the straight blank section to be produced with excellent mechanical properties, ensuring a long service life for the manufactured textile tool.

[0015] The blank section can be particularly advantageously processed by forming with at least one forming tool and at least one counter-die matching that tool. The forming tool and the counter-die are tools that interact during the forming of the blank section in such a way that the desired shape of the blank section with the previously described cross-sectional areas Y(s) is achieved. For this purpose, the at least one forming tool and the at least one counter-die can preferably enclose a cavity together that essentially corresponds to the desired shape of the blank section. The forming is then carried out by die forming. Particularly advantageous mechanical properties can be achieved by cold forming. Furthermore, production by cold forming is more cost-effective and less energy-intensive.

[0016] Further advantages arise when the forming of the blank section is carried out in at least two forming steps. A forming step is characterized by a tool movement of the forming tool that is performed independently of other forming steps. In this way, cross-sectional areas Y(s) can be generated that exhibit even greater surface area differences along the blank section. The textile tool can thus be even better adapted to the stresses under operating conditions. The service life of the manufactured textile tool can therefore be improved. Fig. 1 Figure 1 Fig. 2 shows a textile tool (1) in a blank state (12). Figure 2 Fig. 3 shows an enlarged representation of a straight blank section (8) of the textile tool (1) in the blank state (12). Figure 3 Fig. 4 shows an enlarged view of the blank section (8) after its cross-sectional areas have been machined along a line coordinate (s). Figure 4 Fig. 5 shows a textile tool (1) according to the invention with a shaped hook (3). Figure 5 shows an enlarged view of the hook area (6) of the in Fig. 4 textile tool shown (1). Fig. 6 Figure 6 shows the cross-sections AA, BB and CC of a first embodiment of the in Fig. 5 hook area shown (6). Fig. 7 Figure 7 shows the cross-sections AA, BB and CC of an alternative embodiment of the in Fig. 5 hook area shown (6). Fig. 8 Figure 8 shows the cross-sections AA, BB and CC of another alternative embodiment of the in Fig. 5 shown hook area (6).

[0017] The Figure 1 Figure 1 shows a textile tool 1 in a blank state 12. In this state, the textile tool 1 comprises a straight blank section 8, which extends longitudinally L to a shaft 2 and whose end 9 forms the termination of the textile tool 1.

[0018] The Figure 2Figure 1 shows an enlarged representation of the straight blank section 8 of the textile tool 1 in the blank state 12. Starting from the end 9 of the straight blank section 8, a line coordinate s runs along a center line 7 extending centrally through the textile tool 1. The center line 7 is in Fig. 2 shown with a dashed line. The straight blank section 8 has a consistently large cross-section Y(s) along the line coordinate s, which corresponds to the in Fig. 2 The cuts GG and HH shown to the right of the textile tool 1 are illustrated.

[0019] In the Fig. 3 and 4 The textile tool 1 is shown before and after the blank section 8 has been shaped into the hook 3. As in Fig. 3As can be seen, the straight blank section 8 is first processed such that the cross-sectional area Y(s) of the blank section 8 increases along the line coordinate s starting from the end 9 of the blank section 8 until it reaches a maximum cross-sectional area Ymax of the blank section 8, and then decreases again within the blank section 8. The course of the cross-sectional area Y(s) of the blank section 8 is illustrated by the sections DD, EE, and FF, which follow one another in the above order, starting from the end 9 of the blank section 8 along the line coordinate s.Along the path s starting from end 9 of blank section 8 towards shaft 2, blank section 8 initially has a small cross-sectional area Y(si) at section DD at path s1. This area increases continuously until the maximum cross-sectional area Ymax = Y(s2) is reached at section EE at path s2. Subsequently, the cross-sectional area decreases again, so that blank section 8 has a smaller cross-sectional area Y(ss) at section EE at path s3.

[0020] The Figure 4 The textile tool 1 is shown after a hook 3 has been formed by reshaping the blank section 8. The end 9 of the blank section 8 forms the hook point 5 of the hook 3. The area in the longitudinal direction L from the hook point 5 to the front end 4 of the textile tool 1 is the hook area 6.

[0021] In the Figure 5This hook area 6 is shown enlarged to illustrate the features of the hook 3 according to the invention. Due to the bending 11 of the hook 3, the center line 7 in the hook area 6 also has a curved path. For the following considerations, it is assumed that the distance coordinate s runs from the hook tip 5 along this now curved center line 7.

[0022] In the Figure 6 The three cuts AA, BB and CC through the hook 3 are from Fig. 5 The diagram shows the sections traversed from the hook tip 5 in the aforementioned order. The position of each section is shown in the enlarged view of the hook area 6. Fig. 5The sections are represented by dashed lines. The cutting planes are oriented such that their normal vector is tangent to the center line 7. The cutting plane thus corresponds to the plane spanned by the cross-sectional height direction Hund and the cross-sectional width direction B. The cross-sectional area X(s) of the hook 3 has a circular contour in all three sections, but the size of the cross-sectional area X(s) differs. In section AA, which lies at the line coordinate s 1 (s = s 1 ) in the hook tip section 10, the hook 3 has a comparatively small cross-sectional area X(si). However, further along the line coordinate, the cross-sectional area X(s) increases until the maximum cross-sectional area X max of the hook 3 is reached in section BB at the line coordinate s 2.Starting from this maximum cross-sectional area X max, the cross-sectional area then decreases again in the direction of the shaft 2, as shown by the section CC with the reduced cross-sectional area X red at the line coordinate s 3.

[0023] Figure 7 shows an alternative embodiment of the in Fig. 5 and Fig. 6 textile tool 1 shown. This embodiment differs from the first embodiment only in the size and shape of the cross-sectional areas X(s). The representation of the Fig. 5 Therefore, this embodiment does not differ, which is why this embodiment can only be determined based on the in Fig. 7 The cuts shown are AA, BB and CC, which correspond to the one in Fig. 5The sections shown correspond to the sections described below. In section AA at the line coordinate si, which lies in the hook tip section 10, the cross-sectional area X(si) has a teardrop-shaped contour that increases in width from top to bottom in the cross-sectional height direction H. Due to the smaller width in the upper region of the cross-sectional area X(si), a slider used to close the hook 3 can be guided more effectively on this hook tip section 10. This is particularly advantageous due to the increased flexibility of the hook 3 of the textile tools 1 according to the invention and, despite this flexibility, allows the use of sliders in conjunction with the textile tools 1 according to the invention. Further along the line coordinate s, the cross-sectional area X(s) increases and changes its shape, so that the maximum cross-sectional area Xmax is reached at the line coordinate s2 in the bend 11 of the hook 3 and has an oval contour there.Therefore, X(s 2 ) = X max . The oval contour is oriented such that the cross-sectional area X(s 2 ) has a greater height in the vertical direction H than its width in the horizontal direction B. This ensures that the textile tool 1 achieves a very long service life even when processing highly abrasive yarn. Towards the shaft 2, the cross-sectional area X(s) then decreases again until, at the line coordinate ss, the reduced cross-sectional area X red = X(s 3 ).

[0024] Figure 8 shows another alternative embodiment of the in Fig. 5 and Fig. 6 textile tool 1 shown. This embodiment is also exclusively based on the one shown in Fig. 8 The cuts shown are AA, BB and CC, which correspond to the one in Fig. 5 The sections shown correspond to those described. Fig. 8 The illustrated embodiment largely corresponds to the one shown in Fig. 6in the first embodiment shown. However, the contour of the cross-sectional area X(si) at the line coordinate s 1 in the hook tip section 10 and the contour of the reduced cross-sectional area X red at the line coordinate s 3 are changed in this embodiment. In the Fig. 8 In the illustrated embodiment, the cross-sectional area X(si) has a substantially rectangular contour with rounded edges instead of a circular contour. The reduced cross-sectional area Xred has a contour with planar boundary surfaces pointing in the width direction B instead of a circular contour. Surprisingly, the modified contours further increase the service life of the textile tool 1 according to the invention. Furthermore, the hook 3 of the textile tool 1 with changing cross-sectional contours can be manufactured particularly cost-effectively using the method described above. Reference symbol list 1 Textile tool 2 shaft 3 Hook 4 Front end of the textile tool (1) 5 hook point 6 Hook area 7 center line 8 blank section 9 End of blank section (8) 10 Hook tip section 11 Bending of the hook (3) 12 Textile tool blank B Latitude H Cross-sectional height direction L Longitudinal direction s Route coordinates X(s) Cross-sectional area of ​​the hook 3 X max Maximum cross-sectional area X red Reduced cross-sectional area Y(s) Cross-sectional area of ​​blank section 8 Y max Maximum cross-sectional area of ​​the blank section 8

Claims

1. Textile tool (1) suitable for use in textile machines, comprising: • a shank (2) extending substantially in a longitudinal direction (L), • a hook (3) extending longitudinally (L) towards a front end (4) of the textile tool (1) to the shank (2) and terminating with a hook point (5), • wherein the hook (3) is formed by deforming an originally straight blank section (8) adjoining the shank (2) to form a bend (11), • and wherein the hook (3) forms a hook area (6) extending longitudinally (L) from the hook point (5) to the front end (4) of the textile tool (1). characterized by the fact that • the cross-sectional area (X(s)) of the hook (3) increases along a line coordinate (s) starting from the hook tip (5) and after reaching a maximum cross-sectional area (X max) decreases again, • where the distance coordinate (s) runs along a center line (7) extending centrally through the textile tool (1).

2. Textile tool (1) according to the preceding claim characterized by the fact that the maximum cross-sectional area (X max ) 10% to 100%, but preferably 15% to 50%, is larger than a reduced cross-sectional area (X) red ) of the hook (3), which in the hook area (6) starting from the maximum cross-sectional area (X) max ) in the direction of the shaft (2).

3. Textile tool (1) according to one of the preceding claims characterized by the fact that the maximum cross-sectional area (X max ) 1% to 100%, but preferably 10% to 25%, is larger than the cross-sectional area in a hook tip section (10) which is located directly in front of the bend (11) of the hook (3) starting from the hook tip (5).

4. Textile tool (1) according to one of the preceding claims characterized by the fact thatthe cross-section of the hook (3) has a substantially round, oval, square, rectangular, trapezoidal, triangular and / or polygonal contour.

5. Textile tool (1) according to the preceding claim characterized by the fact that the cross-section of the hook (3) in the hook tip section (10) has a substantially rectangular, square or teardrop-shaped contour and in the area of ​​the bend (11) of the hook (3) has a substantially oval or round contour.

6. Textile tool (1) according to one of the preceding claims characterized by the fact that the maximum cross-sectional area (X max ) lies in the hook arc, where the hook arc is the section of the hook (3) in which the midline (7) is curved.

7. Textile tool (1) according to one of the preceding claims characterized by the fact that the cross-section of the hook (3) with the maximum cross-sectional area (X) max ) has a substantially oval contour.

8. Method for manufacturing a textile tool (1) according to one of the preceding claims, wherein the manufacturing from a blank state (12) is carried out with the following process steps in the specified order: • Machining a blank section (8) of the textile tool (1) that is straight in the blank state (12) and adjoins the shaft (2), such that the cross-sectional area (Y(s)) of the blank section (8) increases along the line coordinate (s) starting from the end (9) of the blank section (8) and within the blank section (8) starting from a maximum cross-sectional area (Y max ) of the blank section (8) decreases again, • forming the hook (3) by reshaping the straight blank section (8), • wherein the end (9) of the blank section (8) forms the hook point (5) after forming the hook (3).

9. Procedure according to the preceding claim characterized by the fact thatthe cross-sectional areas Y(s) of the straight blank section (8) are machined by forming with at least one forming tool, by machining processes and / or by separating manufacturing processes.

10. Procedure according to the foregoing claim characterized by the fact that the blank section (8) is processed by forming with the at least one forming tool and at least one counter-form suitable for the at least one forming tool.

11. Method according to one of the foregoing claims characterized by the fact that the forming of the blank section (8) takes place in at least two forming steps.

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