CN111101288B

CN111101288B - Composite needle of warp knitting machine

Info

Publication number: CN111101288B
Application number: CN201910141986.7A
Authority: CN
Inventors: K.布兰德尔; K.奥布曼
Original assignee: Carlmeyerstol R & D Co ltd
Current assignee: Carlmeyerstol R & D Co ltd
Priority date: 2018-10-25
Filing date: 2019-02-26
Publication date: 2022-05-24
Anticipated expiration: 2039-02-26
Also published as: KR102285359B1; CN111101288A; ES2890929T3; EP3643823A1; KR20200047327A; TWI766180B; EP3643823B1; TW202016384A

Abstract

The invention relates to a compound needle of a warp knitting machine, in particular to a compound needle (1) of a warp knitting machine, which is provided with: a needle (2) having a hook (3); a transition region (4) coupled to the hook (3), the cross-section of which is enlarged in a direction away from the needle (2); and a rod (5). The warp knitting machine can be operated reliably even in the case of difficult threads to be processed. For this purpose, the transition region (4) has an edge profile (14,15) which varies continuously between the hook (3) and the shank (5).

Description

Composite needle of warp knitting machine

Technical Field

The invention relates to a warp knitting machine compound needle (Ketten wirkmaschene-Schiebernadel) with a needle head having a hook portion, a transition region (the cross section of which expands in the direction away from the needle head) which is connected to the hook portion, and a shaft portion.

Background

Such a warp knitting machine compound needle is known, for example, from DE 2537502 a 1.

In operation of the warp knitting machine, the compound needle must absorb forces during coil formation. The compound needle is, for example, bent sideways as a result of load bearing on the thread laying (Verlegung), compressed as a result of thread tension (Fadenzug) and fabric take-up (Warenabzug) in the longitudinal and transverse directions and load bearing on the longitudinal axis as a result of compound needle lifting, in which case the compound needle forms a coil which must slide from the region of the hook onto the shank.

The composite needle is produced, for example, from a plate by stamping or from a wire by hammering. After the punching, the punching burr must be removed, which can be achieved, for example, by barrel polishing (Gleitschleifen). All sharp edges are also slightly rounded here.

The load of the composite needle described above also depends, inter alia, on the thread used for knitting. The more inelastic the wire, the greater the load overall. When, for example, mosquito nets (Moskitonetz) are to be produced, monofilaments (monofilame) are used for the lines, which monofilaments are relatively stiff. The load of the compound needles during operation of the warp knitting machine is so great even in the case of relatively small counts, that even increasingly leads to malfunctions which can propagate up to the breaking of the compound needles.

Disclosure of Invention

The aim of the invention is to be able to reliably operate a warp knitting machine even in the case of difficult threads to be processed.

This object is achieved in the case of a warp knitting machine compound needle of the type mentioned at the outset in that the transition region has an edge profile (kantenporrieung) which varies continuously between the hook and the shank.

The composite needle can thus remain substantially unchanged in its structure. In particular, the composite needle can be embodied so as to be reinforced up to a certain limit in order to be able to absorb the loads caused by the thread to be processed. The composite needle is however provided in a targeted manner with a predetermined edge profile, which can be produced, for example, by a machining step. Alternatively, the edge profile can also be produced by stamping. By means of the edge shaping, it can be achieved that the loops formed at the hook can slide more easily onto the shank when the composite needle is raised.

Preferably, the edge profile is configured as a radius. Thereby further facilitating movement of the coil from the hook portion onto the stem portion.

Preferably, the radius has a curvature that increases away from the hook. The transition region has a cross section that widens from the hook to the shank. In synchronization with the enlargement of the cross section, the curvature of the edge profile also increases in the direction away from the hook, so that the transition region becomes more and more "angular" (eckig). But in practice no sharp corners are constructed.

Alternatively or additionally, the edge shaping can be configured as a chamfer. A blend of rounding and chamfering is possible. An increasing curvature then corresponds to a decreasing chamfer width.

In a preferred embodiment, the ratio between the area determined by the width and depth of the transition region and the cross-sectional area of the transition region widens from the hook to the shank. This condition applies at any distance from the hook. In other words, the closer to the hook, the greater the area of the edge molding vacated (sometimes referred to as released) by the area determined by the width and depth of the transition zone. The width is here the direction in which the compound needles are arranged side by side in the guide bar of the warp knitting machine. The depth is perpendicular thereto and perpendicular to the direction of longitudinal extension of the composite needle.

Preferably, the ratio is at most 0.8 at the first end of the transition region adjacent to the hook. In other words, the actual cross-section of the transition region need only substantially pass through 80% of the area available by the product of the width and the depth of the transition region.

It is also advantageous if the ratio is at least 0.85 at the second end of the transition region adjacent to the shank. The edge profiling here results in that a maximum of 15% of the area defined by the width and depth of the transition region is not covered by the cross section of the transition region.

Preferably, the front side of the composite needle has a first edge profile and the rear side of the composite needle has a second edge profile, wherein the first edge profile and the second edge profile are configured differently. This takes account of the fact that a groove is formed on the front side of the compound needle, in which groove the core moves during operation of the warp knitting machine.

Preferably, the first edge formation has a first maximum radius of curvature which is less than the thickness of the wall bounding the core groove (Schiebernut). Whereby the edge molding ends before it reaches the core groove. The geometry of the core groove can be retained unchanged.

In a preferred embodiment, it is provided that the second edge profile has a maximum second radius of curvature which lies in the range from 10% to 30% of the width of the composite needle. The largest second radius of curvature is therefore relatively large.

It is also advantageous if the edge shaping continues in the shank. The edge profile can, for example, end in the shaft (auslaufen), and therefore does not have to end directly with the end of the transition region.

It is also advantageous that the edge shaping is confined within the stitch forming area of the composite needle. The stitch forming area corresponds substantially to the lift or lift height of the compound needle when the warp knitting machine is in operation. Edge shaping protruding beyond this is not necessary.

Drawings

The invention is described hereinafter with reference to the drawings according to preferred embodiments. Wherein:

figure 1 shows a perspective view of a warp knitting machine compound needle from two viewing directions,

FIG. 2 shows an enlarged representation of the compound needle in the regions A and B according to FIG. 1 between the needle head and the shaft, and

fig. 3 shows a side view and two cross-sectional views of a composite needle.

Detailed Description

Like elements are provided with like reference symbols in all the figures. Fig. 1a and 2a show the compound needle from the left rear side, while fig. 1b and 2b show the compound needle from the right front side.

The warp knitting machine compound needle 1 has a needle head 2 having a hook portion 3.

Adjoining the hook 3 is a transition region 4, the cross-section of which widens in the direction away from the needle 2. The shaft 5 adjoins the transition region 4, at the end of which facing away from the needle 2a stitch 6 is arranged. The shank 5 has a bar support surface 7 adjacent to the stitch 6.

Fig. 1a shows the back side 8 of the needle, while fig. 1b shows the front side 9 of the needle. A core groove 10 is formed in the front side 9. The core recess serves to accommodate the core during operation of the warp knitting machine, with which the tucking space (fangrum) 11 is closed when the needle pulls the thread through the stitch (which has been previously formed on the area 12 where the stitch is formed) during the stitch forming process.

As can be seen, the cross-section of the transition region 4 increases from the needle 2 to the shaft 5. Correspondingly, when the compound needle 1 is raised for the next loop forming process, the loops already formed in the area of the needle head 2 must be widened in order to pull the warp thread through the loops previously formed on the compound needle again. This is generally known.

In the case of a wire which can be processed with difficulty, since the wire is, for example, relatively stiff, large forces act on the composite needle 1 in the case of such a coil forming process. Due to the laying line, the composite needle 1 is subjected to a load and bends laterally, i.e. in the width direction. Due to the thread stretch and fabric take-up, the compound needles are loaded in the longitudinal direction and in the depth direction. Due to the shape of the compound needle 1, the compound needle 1 is compressed in the longitudinal axis when it is lifted by being stressed by the coil sliding from the needle head 2 onto the shaft 5. The technical material, i.e. the thread or the formed coil, is also strongly stressed during the lifting, since the coil must slide from the needle 2 onto the shaft 5 and is strongly widened there. This widening can result in up to three times the size of the coil.

The reinforcement by the composite needle 1 can only withstand stresses to a limited extent. Stiffening of the width of the composite needle 1, i.e. parallel to the bar support surface 7, is only possible to a limited extent, since the thickness of the composite needle 1 that can be influenced by such stiffening is often already determined by the count (i.e. the number of composite needles per inch). Stiffening in the depth direction, i.e. in the direction between the back side 8 and the front side 9, is likewise only possible to a limited extent. Furthermore, the transition between the needle 2 and the shaft 5 cannot be carried out over a very short distance, since the coil may then widen too quickly.

Other approaches are now chosen in order to keep the load on the composite needle 1 small when the coil is widened. The compound needle 1 is provided with an edge profile which varies continuously between the hook 3, i.e. the needle tip 2, and the shaft 5. This continuous change does not have to be realized continuously over the entire distance between the needle 2 and the shaft 5. However, this continuous change should be realized in the coil-forming region 12, in which the coil must be widened during operation. This portion extends from the needle 2 approximately up to the position 13. The location 13 can however also be located at a different location in the case of different types of composite needles 1. The portion 12 forming the coil typically has a length of 7mm to 17 mm.

The edge shaping is composed of a first edge shaping 14 at the front side 9 of the compound needle 1 and a second edge shaping 15 at the rear side 8 of the compound needle 1. The first edge molding 14 and the second edge molding 15 are configured differently.

The first edge contour 14 and the second edge contour 15 can be configured, for example, as a radius. The rounding can follow a circumferential line in cross section, even if this is not necessarily necessary. The circumferential line is applied for the purpose of simplifying the explanation. In this case, the radius of curvature can be defined. In general, the edge shapes 14,15 each have a rounding, wherein the feature here is that each rounding has a curvature which increases away from the hook 3. This means that the radius of curvature decreases in a direction away from the needle 2 on the basis of the curvature of the circumferential line.

Alternatively to the rounding, the first edge contour 14 and the second edge contour 15 can also be designed as chamfers. It is also possible to configure one of the edge shapes 14,15 as a rounding and the

other edge shape

14,15 as a chamfer or to make the rounding in one or both edge shapes 14,15 possible to transition into a chamfer or vice versa. The increased curvature corresponds to a reduced width of the chamfer, i.e. the edge profile is then "sharper".

It is now possible to define an area which is formed by the product of the width (i.e. the spacing between the left-hand side face 16 and the right-hand side face 17) and the depth (i.e. the spacing between the front side 7 and the rear side 8). The ratio of the cross-sectional areas at the same point of the transition region 4 can be set. This ratio now expands from the hook 3 to the stem 5.

Thus, the ratio can be at most 0.8 at the first end of the transition region 4 (which is adjacent to the hook 3), i.e. the cross-sectional area is 80% of the area defined by the product of width and depth. At the other end of the transition region 4, the ratio can be at least 0.85, i.e. the cross-sectional area here occupies at least 85% of the area formed by the product of width and depth.

As can be seen from the drawings, the second contour 15 at the rear side 8 has a smaller curvature, i.e. a larger radius of curvature, than the first edge contour 14 at the front side 9 of the composite needle 1.

The radius of curvature of the first edge profile is furthermore limited by the core groove 10. The core groove 10 is constructed between two

walls

18, 19. The first edge formations 14 each have a first, largest radius of curvature which is smaller than the thickness of the

walls

18,19 bounding the core groove 10.

The second edge profile on the other hand has a maximum second radius of curvature which lies in the range from 10% to 30% of the width of the composite needle 1 (i.e. the distance between the left flank 16 and the right flank 17).

The edge profiles 14,15 can continue in the shaft 5 in a manner not shown in more detail. As set forth above, but sufficient are: the

edge formations

14,15 are limited to the loop forming area 12 of the composite needle 1.

The hook 3 often has a circular cross-section. At least the hook 3 likewise has an edge profile with a corresponding curvature. It can now be ensured that the first edge profile 14 and in particular also the second edge profile 15 continuously merge into the hook 3.

Fig. 3 shows a side view of the composite needle 1, in which two sectional views C-C and D-D can be seen. Fig. 3b shows a cross-sectional view of the composite needle 1 along line C-C. Fig. 3c shows a cross-sectional view of the composite needle 1 along the line D-D. The change in edge profile can be clearly seen by comparing fig. 3b with fig. 3 c.

Claims

1. A warp knitting machine compound needle (1) with: a needle (2) having a hook (3); a transition region (4) coupled to the hook (3), the cross-section of which is enlarged in a direction away from the needle (2); and a shaft (5), wherein the transition region (4) has an edge profile (14,15) which varies continuously between the hook (3) and the shaft (5), characterized in that the edge profile (14,15) is designed as a radius, wherein the radius has a curvature which increases away from the hook (3).

2. The compound needle as claimed in claim 1, characterized in that the edge shaping (14,15) is configured as a chamfer.

3. Composite needle according to claim 1 or 2, characterized in that the ratio between the cross-sectional area of the transition zone (4) and the area determined by the width and depth of the transition zone (4) expands from the hook (3) to the shank (5).

4. A composite needle according to claim 3, characterized in that the ratio is at most 0.8 at the first end of the transition region (4) adjacent to the hook (3).

5. A composite needle according to claim 3, wherein the ratio is at least 0.85 at a second end of the transition region (4) adjacent to the shaft (5).

6. The composite needle according to claim 1 or 2, characterized in that the front side (9) of the composite needle (1) has a first edge contour (14) and the back side (8) of the composite needle (1) has a second edge contour (15), wherein the first edge contour (14) and the second edge contour (15) are configured differently.

7. Composite needle according to claim 6, characterized in that the first edge profile (14) has a maximum first radius of curvature which is smaller than the thickness of the walls (18,19) bounding the core groove (10).

8. Composite needle according to claim 6, characterized in that the second edge shaping (15) has a maximum second radius of curvature which lies in the range of 10% to 30% of the width of the composite needle (1).

9. Composite needle according to claim 1 or 2, characterized in that the edge shaping (14,15) continues in the shaft (5).

10. A composite needle according to claim 1 or 2, characterized in that the edge shaping (14,15) is limited within a stitch forming area of the composite needle (1) which extends from the needle head (2) over a length in the range from 7mm to 17 mm.