TWI826853B - Warp knitting tool bar for a warp knitting machine - Google Patents

Abstract

A warp knitting tool bar of a warp knitting machine is specified, with a base body (1), which is designed as a hollow profile. The aim is to be able to minimise problems associated with temperature changes under high mechanical loads. For this purpose, provision is made for the base body to be formed from steel.

Description

Warp knitting machine tool bar

Field of invention

The invention relates to a warp knitting tool bar for a warp knitting machine, which has a base body designed as a hollow profile.

Background of the invention

This warp knitting tool bar is a known technology, for example from EP 3 216 903 B1.

Such warp knitting tool bars are usually designed with a base body formed from a light metal such as magnesium or aluminum or from a fiber-reinforced plastic material. These materials are often used to keep the mass of warp knitting tool bars small. Many warp knitting tool bars involved in the warp knitting process must be accelerated and decelerated twice during the stitch forming operation. The smaller the mass of the warp-knitted bar, the smaller the force acting on the warp-knitted bar. This means that driving power and general wear can be kept low.

Warp-knitted tool bars made of fiber-reinforced plastic also have the advantage of high-temperature stability. The thermally induced length changes (ie thermal expansion) of the warp knitting tool bars are minimal. However, the manufacturing cost is relatively high.

Another warp knitting tool bar is known from DE 1 585 174 B. Here, the bar is formed from a light metal, which is joined on one side to a steel strip prestressed in the longitudinal direction. Here, the aim is to minimize thermal expansion.

If high fabric release forces occur, there is increased wear on the contact surfaces between the warp knitted fabric (ie the warp threads forming the warp knitted fabric) and the bars or other parts of the warp knitting machine to which the warp knitted fabric comes into contact. surface. An example of this situation is the so-called "clipped edge". For high fabric release forces, it is also important to have small deformations of the machine elements involved. For this reason, steel is used as material for fixed parts or parts that move less, specifically, steel plated with chromium on the surface in contact with the wire or warp knitted fabric.

However, with this material choice, problems associated with temperature changes arise. Steel has a different thermal expansion behavior than, for example, fiber-reinforced plastics or even light metals such as aluminum or magnesium.

Summary of the invention

The invention is based on the aim of minimizing problems associated with temperature changes under high mechanical loads.

This object is achieved with a warp-knitting tool bar of the type mentioned above, in which the base body is formed from steel.

With this design, the same material (ie steel) can be used for all bars and other parts running in the longitudinal direction of the warp knitting machine (ie in the working width). Since the base body is designed with a hollow profile, lightweight steel can also be used in this case, so that the mass of the warp-knitted bars can again be kept low.

The hollow profile preferably has at least one flat steel profile. Flat steel profiles may also be referred to as "plates" for short. Several flat steel profiles can be joined to form a hollow profile of the base body. For example, the joining process can take the form of welding, stamping, crimping or riveting.

Here, the flat steel profile is optimally formed. The forming process can take the form of bending or buckling. In the case of bending, the bending line is parallel to the longitudinal extent. In the case of buckling, the line at the center of the curve radius is also parallel to the longitudinal extent. Forming can be used to increase the mechanical stiffness of individual flat steel profiles. Therefore, the flat steel profile in question can be designed to be relatively thin. The flat steel profile can have a plurality of forming zones in the circumferential direction of the warp knitting tool bar.

Preferably, at least one flat steel profile has two areas that join each other. The flat steel profile then forms loops or loops in cross-section. The joining of the two areas can be performed directly, for example by welding the two areas together. It is also possible to arrange another element between the two areas, which element protrudes from the base body and serves, for example, as a mounting surface for the warp knitting tool.

Alternatively or additionally, at least two flat steel profiles may be provided that engage one another. In this case, the hollow contour of the base body is formed from a plurality of flat steel contours. Here, at least one or each flat steel profile can also have at least one curve or at least one bend.

At least one wall of the hollow profile preferably has at least one thickened region in which the attachment profile is provided. For example, the attachment profile can be designed as an internal thread. For example, thickened areas can be created by thermal drilling to create internal threads. Subsequently, the material displaced from the hole forms a thickened region.

The hollow profile preferably has at least two different wall thicknesses. Subsequently, the wall thickness can be adapted to different load situations. In some cases, the acceleration in a first direction is greater than the acceleration in a second direction transverse to the first direction. Subsequently, the wall thickness that must withstand the acceleration in the first direction can be chosen slightly larger.

It is also advantageous for at least one wall of the hollow profile to have at least two different wall thicknesses. It is also conceivable to have different wall thicknesses in one wall.

It is also advantageous for the hollow profile to have a maximum average wall thickness in the range of 1 to 10 mm, in particular in the range of 2 to 5 mm. Subsequently, the hollow profile can be formed with a relatively small mass. Wall thickness can be kept small.

At least one wall of the hollow profile preferably has at least one opening. By means of the opening, the mass of the base body can be reused.

The hollow profile preferably has a plurality of regions in the longitudinal direction. That is, instead of using one continuous hollow profile as the base body, multiple zones are used across the working width of the warp knitting machine. This has the advantage that the absolute thermal expansion of each zone is less than the thermal expansion of the bar as a whole. Using this method, the displacement of the warp knitting tool relative to other warp knitting tools can be kept small.

The abutment is preferably arranged between two areas on the bar of the warp knitting machine. This situation allows these sectors to be located in a convenient manner.

The hollow profile preferably has at least one reinforcing rib, which is designed in particular as a flat steel profile. Reinforcing ribs are used to reinforce the hollow profile so that the hollow profile can be relatively weak in other dimensions. If flat steel profiles are used, the stiffening ribs can be produced at low cost.

Preferably, the reinforcing rib is arranged at at least one end of the section. This situation promotes production.

It is also advantageous if the hollow profile has at least one reinforcing rib. For example, the reinforcing ribs can be formed by means of stamping.

Detailed description of preferred embodiments

FIG. 1 schematically shows a base body 1 of a warp knitting tool bar, which base body 1 is designed as a hollow profile and thus forms a hollow profile. The base body 1 has a cavity 2 which is formed by a flat steel profile 3 . The flat steel profile buckled multiple times. The flat steel profile 3 has two areas 4 , 5 which are joined to each other by a warp knitting tool holder 6 . In the present case, the regions 4, 5 are arranged at each end of the flat steel profile 3 extending parallel to the longitudinal direction. However, this is not mandatory. For example, areas 4, 5 are welded to the warp knitting tool frame 6. Other possible joint forms are conceivable.

In the present case, the flat steel profile 3 forming the base body 1 has a total of five curves 7 to 11 . The apex of each curve 7 to 11 is parallel to the longitudinal extent of the base body 1 .

The flat steel profile 3 has a thickened area 12 . A threaded hole 13 is provided in the thickened area 12 with which the base body 1 can be attached to a rod of a warp knitting machine (not shown).

In a similar manner, the warp knitting tool holder 6 has a thickened area 14 with holes 15 so that warp knitting tools (not shown in Figure 1) can be attached to the warp knitting tool holder 6. The warp knitting tool rack 6 can also be designed as a flat steel profile.

The thickened regions 12, 14 may be produced by drilling the holes 13, 15 by means of heat flow. This situation causes a displacement of material from the flat steel profile 3 or the warp knitting tool frame 6, which later forms the thickened areas 12, 14. Attachment contours, such as internal threads, may be provided in the holes 13, 15.

This internal thread can also be produced by other means, such as by using blind rivet nuts or weld nuts or captive nuts. However, production by means of hot flow drilling is advantageous since it does not increase the mass of the base body 1 .

FIG. 3 shows a second embodiment of the base body 1 as a hollow profile, in which a plurality of flat steel profiles 16 to 19 are assembled. Here, the flat steel profile 16 is designed as a flat profile. The flat steel profile 19 is designed as an L-shaped profile and therefore has a curve. The other two flat steel profiles 17, 18 are curved and therefore have rounded corners. The flat steel profile 16 is joined to the flat steel profile 17 along a weld seam 20 . There is a second weld seam 21 between the flat steel profile 16 and the flat steel profile 18 . There is a third weld seam 22 between the flat steel profile 18 and the flat steel profile 19 . There is a fourth weld seam 23 between the flat steel profile 17 and the flat steel profile 19 . Weld seams 20 to 23 join adjacent flat steel profiles in each case.

The L-shaped profile of the flat steel profile 19 contributes to the stiffness of the base body.

FIG. 4 shows a modified form of the embodiment of the base body 1 .

Here, the flat steel profile 16 is designed with two sections 24 , 25 which are joined together by a curve 26 . Region 24 has a greater wall thickness than region 25 . The region 25 of the flat steel profile 16 has a wall thickness that is greater than the wall thickness of the flat steel profiles 17 , 18 . The flat steel profile 16 is in turn joined to the flat steel profile 17 by a weld seam 20 . The flat steel profile 16 is joined to the flat steel profile 18 by a weld seam 21 . The flat steel profile 19 is joined to the flat steel profile 18 by a weld seam 22 . The flat steel profile 19 is joined to the region 24 of the flat steel profile 16 and to the flat steel profile 17 by a weld seam 23 .

FIG. 5 shows a design of the base body 1 corresponding to the base body 1 of FIG. 4 .

In contrast to the design in Figure 4, the flat steel profile 17 is mostly planar in design. Only in the area of the weld seam 20 is the flat steel profile 17 slightly inclined, so that a relatively large contact area is formed between the two flat steel profiles 16 , 17 .

Figures 6 and 8 show another design of the base body 1, in which two further features are added.

In one feature, the base body 1 is provided with reinforcing ribs 27, 28 on both end faces in its longitudinal direction. The reinforcing ribs 27, 28 can be welded to the flat steel profiles 16 to 19, for example. The reinforcing ribs 27, 28 may have openings 29, 30 in order to make the reinforcing ribs 27, 28 less massive. The reinforcing ribs 27, 28 can also be designed as flat steel profiles.

In addition, the flat steel profiles 16 and 18 are also provided with openings 31 and 32 in order to reduce the mass of the flat steel profiles 16 and 18. Furthermore, the flat steel profile 18 has reinforcing ribs 33 , which can be punched into the flat steel profile 18 , for example.

It should be emphasized that the reinforcing ribs 27, 28 can be provided in all base bodies. In the design according to Figures 6 and 8, reinforcing ribs 27, 28 are arranged at each end of the base body. In the design according to FIG. 7 , the reinforcing rib 27 can also be arranged in the center of the base body 1 , that is to say in the cavity 2 . The design according to Figure 7 is described in more detail below.

The openings 31 , 32 can be provided not only in the flat steel profiles 16 , 18 but in principle in all flat steel profiles, ie also in the flat steel profiles 3 , 17 , 19 . Reinforcing ribs 33 can also be provided in all flat steel profiles 3, 16 to 19.

In the design according to FIG. 7 , only three flat steel profiles 16 , 17 , 19 are provided, of which only the flat steel profiles 16 , 17 are joined to one another by means of weld seams 20 . The reinforcing ribs 27 join the two flat steel profiles 16 , 17 and at the same time join the flat steel profiles 16 , 17 to the flat steel profile 19 , which in turn is L-shaped. For example, the joining can be carried out by means of welding. In the design according to FIG. 7 , the hollow profile is open on the side where the reinforcing ribs 27 protrude beyond the flat steel profiles 16 , 17 .

Figures 9 to 11 show the base body 1 and the warp knitting tools 34, which in this embodiment example are designed as warp knitting needles. Other warp knitting tools are also possible.

In the design according to Figure 9, the needle holder 35 is joined to the base body, as illustrated in Figures 1 and 2. The needle holder 35 is simultaneously engaged to the warp knitting tool holder 6 . The connection is made here by means of screws screwed into holes 15 . The warp knitting tool 34 is held in the needle holder 35 by a cover 36 known per se. The needle holder 35 is supported on the rounded corner 11 of the flat steel profile 3 . The rounded corner 11 is adjacent to the warp knitting tool holder 6 .

FIG. 10 shows the base body 1 according to FIG. 3 with a needle holder 35 to which a warp knitting tool 34 in the form of a warp knitting needle is attached. The needle holder 35 is engaged to the flat steel profile 19 . The needle holder 35 is coupled to one leg of the L-shaped flat steel profile 19 and can be supported on the other leg of the L-shaped flat steel profile 19 .

In the design according to FIG. 11 , the needle holder 35 of the warp knitting tool 34 is joined (more precisely welded) to the base body 1 along two welding lines 37 , 38 . A welding line 37 is arranged on the flat steel profile 17 . Another welding line 38 is arranged at one end of the flat steel profile 18 , which end is in this case welded directly to the flat steel profile 17 , ie to the weld seam 39 . In the design according to Figure 11, only three flat steel profiles 16, 17, 18 are provided.

Only base bodies with hollow profiles with different wall thicknesses are shown here in connection with FIG. 4 . However, it will be apparent that different wall thicknesses may be used in other forms of embodiment. For example, different wall thicknesses can be implemented since a single steel plate profile has a different wall thickness than the wall thickness of other flat steel profiles. In other designs, it is also possible to provide flat steel profiles designed with two different wall thicknesses.

In all cases, buckled or curved flat bar profiles can be combined with mostly planar flat bar profiles.

In all cases, relatively low wall thicknesses are used. The wall thickness of the hollow profile and of the flat steel profile ranges from 1 to 10 mm, in particular from 2 to 5 mm. Overall, the mass of the base body 1 can be kept low, since the average wall thickness lies in the range of 1 to 10 mm, in particular in the range of 2 to 5 mm.

The warp knitting tool bar formed by means of the base body 1 has a plurality of sections. For example, one section has a length in the range of 1 to 1.5 m. Reinforcing ribs 27, 28 may be provided at each end of such zones, as described above. If necessary, other reinforcing ribs 27 can also be provided in the center of such areas.

The section preferably ends where the warp knitting machine has a bar with which the warp knitting tool bars are moved.

1:Matrix 2:Cavity 3,16~19: Flat steel profile 4,5:Area 6: Warp knitting tool holder 7~11,26: Curve 12,14: thickened area 13,15:hole 20,39:weld 21:Second weld 22:Third weld 23: The fourth weld 24,25:District 27,28: Reinforced ribs 29,30,31,32: Opening 33: Reinforcement ribs 34: Warp knitting tools 35: Needle holder 36:Lid 37,38:Welding wire

The present invention will be described below with reference to preferred examples of embodiments and in conjunction with the accompanying drawings. here: Figure 1 shows a schematic cross-section of a first form of embodiment of a base body of a warp knitting tool bar, FIG. 2 shows the base body according to FIG. 1 in a perspective view, Figure 3 shows a schematic perspective view of a second form of embodiment of the base body of a warp knitting tool bar, Figure 4 shows a schematic perspective view of a third form of embodiment of the base body of a warp knitting tool bar, Figure 5 shows a schematic perspective view of a fourth form of embodiment of the base body of a warp knitting tool bar, Figure 6 shows a perspective view of the base body of the warp knitting tool bar according to different angles, Figure 7 shows a schematic perspective view of a part of the base body of a warp knitting tool bar, FIG. 8 shows a schematic perspective view of the base body according to FIG. 6 from a perspective corresponding to FIGS. 2 to 5 , FIG. 9 shows a side view of a warp knitting tool bar with the base body according to FIG. 1 , Figure 10 shows a schematic perspective view of a warp knitting tool bar with a basic body according to Figure 3, and Figure 11 shows a schematic cross-section through a warp knitting tool bar of a seventh embodiment of the base body.

In all figures, identical and corresponding elements are provided with the same reference numerals.

1:Matrix

2:Cavity

3: Flat steel profile

4,5:Area

6: Warp knitting tool holder

7~11: Curve

12,14: thickened area

13,15:hole

Claims (15)

A warp knitting tool bar for a warp knitting machine, which has a base body (1) designed as a hollow profile, characterized in that the base body (1) is made of steel. The warp knitting tool bar according to claim 1, wherein the hollow profile has at least one flat steel profile (3; 16, 17, 18, 19). The warp knitting tool bar as claimed in claim 2, wherein the flat steel profile (3; 16, 17, 18, 19) is formed. Warp knitting tool bar according to claim 2 or 3, wherein at least one flat steel profile (3) has two areas (4, 5) that join each other. Warp knitting tool bar according to claim 2 or 3, wherein at least two flat steel profiles (16, 17, 18, 19) are joined to each other. Warp knitting tool bar according to claim 1 or 2, wherein at least one wall of the hollow profile has at least one thickened area (12, 14) in which an attachment profile (13, 15) is provided. The warp knitting tool bar according to claim 1 or 2, wherein the hollow profile (16, 17, 18, 19) has at least two different wall thicknesses. The warp knitting tool bar of claim 7, wherein at least one wall of the hollow profile has at least two different wall thicknesses. The warp knitting tool bar of claim 1 or 2, wherein the hollow profile has a maximum average wall thickness in the range of 1 to 10 mm, specifically in the range of 2 to 5 mm. Warp knitting tool bar as claimed in claim 1 or 2, wherein at least one wall of the hollow profile has at least one opening (31, 32). The warp knitting tool bar according to claim 1 or 2, wherein the hollow profile has a plurality of sections in the longitudinal direction. The warp knitting tool bar as claimed in claim 11, wherein a bridge is disposed between two sections on a rod of a warp knitting machine. Warp knitting tool bar according to claim 1 or 2, wherein the hollow profile has at least one reinforcing rib (27, 28), the at least one reinforcing rib is specially designed as a flat steel profile. The warp knitting tool bar according to claim 13, wherein the reinforcing rib (27, 28) is arranged at at least one end of a region. The warp knitting tool bar according to claim 1 or 2, wherein the hollow profile has at least one reinforcing rib.