EP3421653B1 - Warp knitting tool bar - Google Patents

Description

The invention relates to an active element carrier with a body which has a longitudinal direction, and an active element receiving.

Such an active element carrier is used in a warp knitting machine to carry knitting tools or knitting elements.

In the production of a knitted fabric similar active elements must also be moved in the same way. This purpose is served by the active element carrier, which is often referred to as "Barre". The active elements are arranged in the active element receiving.

The knuckle carrier usually has to be accelerated and decelerated once in one direction and then accelerated and decelerated in the opposite direction in a stitch forming operation. In some active element carriers, motion in one direction is added to the movement in one direction. It is therefore desirable to keep the mass of the active element carrier as low as possible.

Warp knitting machines are currently produced with working widths of several meters. The active element carrier must then have a length which corresponds to the working width. The subdivision of the active element carrier in several sections in the longitudinal direction is possible, but brings with it other difficulties.

With a low mass and a large length, there is the risk that the active element carrier is excited to vibrate, which has a negative effect on the maximum operating speed of the warp knitting machine.

One has therefore already in DE 10 2006 014 147 B4 proposed to form the body of the active element carrier made of a plastic. Before the plastic hardens, a fastener is installed here, which can be used later for attachment of the active element carrier to other machine elements.

DE 10 2007 038 589 A1 shows a further active element carrier with a body on which an active element receptacle is arranged. The body is formed of a carbon fiber reinforced plastic material and the active element receiving is formed in a plastic order.

DE 10 2010 045 049 B4 shows a method for producing a Wirkwerkzeugbarre using two different materials, wherein a first material for the body and a second material for the active element receiving is provided. Both materials are cured together in a tool.

EP 2 636 781 A1 shows a guide bar of a knitting machine in which a body is connected to a guide frame by a positive connection.

CN 101463530 A shows a bar assembly of a warp knitting machine with a base are fixed to the carrier, which form rails for ingots on which guide pins are attached. The bars can be pushed back and forth in the rails.

EP 1 770 194 A1 shows a further knitting tool bar of a knitting machine, in which a body of a fiber-reinforced plastic is provided, which extends in the longitudinal direction. The body is composed of several elements, each of which extends in the longitudinal direction.

EP 2 770 096 A1 shows a plastic Wirkwerkzeugbarre enclosing a cavity. In the cavity, a reinforcement is provided which divides the cavity into two parts.

DE 10 2004 023 802 B3 shows a Wirkelementbarre with active elements, which is connected via levers to the drive shaft. The active element bars and the associated drive shaft are formed from a plastic material with the same thermal expansion.

The use of carbon fiber reinforced plastics has been proven to form active element carrier with a low mass and a high rigidity and a low thermal expansion. However, carbon fiber reinforced plastics are relatively difficult to machine. The material and the processing lead to relatively high costs.

With the use of lightweight ingots, it is possible to increase the operating speed of a warp knitting machine. However, a high operating speed also leads to a high noise level during operation of the machine.

The invention has for its object to keep the volume during operation of the warp knitting machine small.

This object is achieved with a knuckle-carrier of the type mentioned above in that the body has a skeleton structure having a plurality of Korpusstäben which are interconnected at nodes.

A skeleton structure has a plurality of interconnected elements that have a primary supporting function. The skeleton structure does not form a closed surface, at least to the outside, which acts as a membrane.

Rather, openings are formed between the elements of the skeleton structure so that the skeleton structure has a surface that is not closed. Accordingly, the risk of sound generation by closed surfaces, which could generate sound at a corresponding vibration exposure, minimized. In addition, such a body builds relatively easily. Areas remain free of material between the elements. These "empty" areas thus contribute nothing to the mass of the active element carrier, so that one by leaving out material to a small Total mass of the active element carrier can come. The corpus rods form elements with the primary bearing function.

Preferably, fiber-reinforced plastic rods extend in the longitudinal direction, which are connected to the skeleton structure. The fiber-reinforced plastic rods, in which, for example, the plastic can be reinforced by carbon fibers, have a very high longitudinal stiffness. A change in length, for example due to the influence of heat, is thus negligibly small. In addition, the fiber-reinforced plastic rods can also positively influence the mass-specific flexural rigidity, the mass-specific transverse rigidity and the mass-specific torsional rigidity.

In one embodiment, it is provided that at least one plastic rod is formed continuously over the length of the active element carrier. Thus, the skeleton structure is prevented from stretching in the longitudinal direction.

Alternatively or additionally, it can be provided that at least one plastic rod has an interruption in the longitudinal direction, wherein at least one other plastic rod bridges the interruption. Even with this, a very high longitudinal rigidity can be achieved and a change in length due to external influences, for example heat, can be reliably kept very small.

In a preferred embodiment, it is provided that the skeleton structure has a light metal structure. Although light metal, for example aluminum or magnesium, has a greater specific mass, based on the stiffness, than many of the carbon fiber reinforced plastics. Since, however, only relatively little light metal is required because of the skeleton structure, the mass of the active element carrier can be kept small overall.

In an advantageous embodiment it is provided that the body has a plurality of juxtaposed body elements which have body posts and are interconnected. This facilitates the production. The body elements may be made for example by die casting. Another possibility is to print the carcass elements as three-dimensional objects. In both cases, a shorter overall length is easier to produce than a longer overall length. The entire length of the active element carrier is then achieved by assembling a plurality of such body elements.

Here, it is preferable that the skeleton structure is formed in a plane on which the longitudinal direction is perpendicular, in the manner of a polygon. The skeletal structure may then enclose a polygonal cavity, further contributing to a low overall mass.

It is preferred that at least two plastic rods are arranged at corners of the polygon. However, it is advantageous if more than two plastic rods are used. For example, in the case of a quadrilateral, four plastic rods can be arranged at the four corners of the polygon, resulting in excellent flexural rigidity, excellent transverse shear stiffness, and excellent torsional rigidity.

Preferably, the skeleton structure has first body pillars extending in a width direction transverse to the longitudinal direction and second body pillars extending at an angle in the range of 30 ° to 60 °, in particular from 40 ° to 50 ° to the longitudinal direction. In a particularly advantageous embodiment, the second carcass rods extend at an angle of 45 ° to the longitudinal direction. The first corpus rods then form "slices", so to speak, which are connected to each other by the second corpus rods. Since the second carcass rods are at an angle to the longitudinal direction, a longitudinal expansion of the second carcass rods now leads to a smaller one Compressive stress in the plastic rods when the second body rods expand or contract due to, for example, a temperature change. The compressive stress can be readily absorbed by the plastic rods. A corresponding dimensional change results in the width direction. This is not critical.

It can also be provided that, if necessary, in addition to the bars, which run in the longitudinal direction, only takes bars which enclose an angle in the order of plus / minus 60 ° to the longitudinal direction. The angles may preferably be in a range of 45 ° to 75 °, in particular in a range of 55 ° to 65 °. An angle of 60 ° is preferred. This results in a "accordion-like" training. In particular, when these carcass rods are made of aluminum or another light metal, these carcass rods contribute virtually nothing to the longitudinal stiffness. The longitudinal stiffness is then achieved by the plastic rods. Overall, you can then dimension the active element carrier with relatively little material.

Preferably, the skeleton structure has mounting areas for machine elements and a density of the second bars is greater in the region of the attachment areas than a density of the second bars between the attachment areas. This takes into account the fact that the power flow between the attachment areas is less than at the attachment areas. For example, levers of the warp knitting machine can act on the attachment areas.

Preferably, the body has an upper side and a lower side, and the second body rods are arranged on the upper side and / or on the lower side. This takes account of the burden situation. Preferably, the second carcass rods intersect at least one further first carcass rod between two first carcass rods. This results in a very stable skeleton structure in the manner of a truss.

In a preferred embodiment, it is provided that the first body rods and the second body rods intersect at least one longitudinal edge of the body at a distance from this longitudinal edge and form a multi-finger arrangement. If a first carcass rod and a second carcass rod intersect, then there are two fingers on the longitudinal edge. If two second carcass rods and a first carcass cutting intersect, then there are three fingers in the region of the longitudinal edge of the carcass.

It is preferred here that the active element receptacle is supported on the multi-finger arrangement. This increases the stability of the active element recording.

Fig. 1

eine stark schematisierte Seitenansicht eines Wirkelement-Trägers,

Fig. 2

eine perspektivische Ansicht eines Ausschnitts des Wirkelement-Trägers,

Fig. 3

eine Draufsicht auf den Wirkelement-Träger und

Fig. 4

eine Draufsicht auf eine abgewandelte Ausführungsform des Wirkelement-Trägers.

The invention will be described below with reference to a preferred embodiment in conjunction with the drawings. Herein show:

Fig. 1

a highly schematic side view of an active element carrier,

Fig. 2

a perspective view of a section of the active element carrier,

Fig. 3

a plan view of the active element carrier and

Fig. 4

a plan view of a modified embodiment of the active element carrier.

One in the Fig. 1 and 2 schematically illustrated active element carrier 1 has a body 2 and an active element holder 3. The body 2 is formed as a skeleton structure, that is, it has a plurality of body rods 4-11. The carcass rods are interconnected at junctions 12-15. They form, so to speak, a framework-like structure.

Fiber reinforced plastic rods 16-19 are connected to the skeleton structure. The plastic rods 16-19 are preferably formed as pultruded rods of unidirectional fiber reinforced plastic (CFRP). They have a very high longitudinal stiffness and have virtually no relevant thermal expansion in the longitudinal direction. The length of the plastic rods 16-19 preferably corresponds to the entire length of the active element carrier 1. It can also be provided that at least one of the plastic rods 16-19 is divided in the longitudinal direction and thus an interruption is provided, wherein at least one other plastic rod interruption bridged.

The carcass rods 4-11 are formed at least predominantly of a light metal. As light metal, for example, aluminum or magnesium is considered. Thus, the skeleton structure of the body 2 is formed as a light metal structure. The rods 4-11 can be assembled to form individual body elements, wherein a plurality of such body elements are arranged side by side in the longitudinal direction. The body elements may be glued together, for example. The carcass elements are also connected to the plastic rods 16-19 and are held together by the plastic rods 16-19 in the longitudinal direction. It can be provided that the plastic rods 16-19 are connected with a certain bias to the body elements.

A warp knitting machine typically has, for each knit element carrier, a series of levers which control the movement of the knit element carriers. You can provide one lever each body element.

For attachment of the body to such levers a mounting portion 20 is provided, in the example, a threaded screw can be screwed. In order to increase a thread length, the attachment region may have a thickening 21.

Fig. 1 shows the body in a sectional plane on which the longitudinal direction of the active element carrier is vertical. It can be seen that the skeleton structure is formed in the manner of a polygon with four corners. This does not mean a polygon in the mathematically strict sense. The long sides of the polygon can certainly also have a curvature, as the body post 7 shows. The plastic rods 16-19 are arranged at the corners of the polygon.

The skeleton structure of the body 2 has first bars 4-7 which extend in a width direction, ie transversely to the longitudinal direction of the active element carrier. Only these 4-7 corpus sticks are in Fig. 1 shown. These corpus rods form a kind of "disk" of the skeleton structure.

Furthermore, there are, as in particular in the Fig. 2 and 3 can recognize next to the first Korpusstäben 4-7 second body rods 8-11, which extend at an angle of ± 45 ° to the longitudinal direction. In this case, the second body rods 8 extend at an angle of -45 ° and the second body rods 9 extend at an angle of 45 ° to the longitudinal direction. The longitudinal direction is in Fig. 3 indicated by an arrow 22. The first corpus rods 4-7, however, run in the width direction, ie perpendicular to the longitudinal direction, ie at an angle of 90 °. The width direction is in Fig. 3 represented by a dimension line 23.

The active element carrier 1 has an upper side and a lower side. The term 'top' and 'bottom' refers to the representation of the Fig. 1 , When using the active element carrier 1 in a warp knitting machine different orientations may result. The second body post 8-11 are arranged only at the top and at the bottom, as in Fig. 2 can recognize.

By arranging the second body rods 8-11 at an angle, on the one hand, it is ensured that the body 2 has the necessary cohesion and sufficient flexural rigidity, transverse thrust and torsional rigidity in the longitudinal direction. On the other hand, the risk of longitudinal expansion due to the influence of heat is kept small. If the second body rods 8-11 expand or contract under the influence of temperature, then only part of this expansion takes place parallel to the longitudinal direction 22. The tension generated thereby can be absorbed by the plastic rods 16-19. In the direction of width 23, a change in dimension may result. This is not critical.

How to get in Fig. 3 can recognize, the density of the second body rods 8, 9 in the region of the attachment regions 20 is greater than between the attachment regions 20 or outside of the attachment regions 20. Thus one takes into account the fact that the power flow between the attachment regions 20 is less than at the attachment regions 20th ,

The second body rods 8, 9 are arranged such that they intersect at least one further body stem 7 between two first body rods 7 so that they form a further node 24 here. In the region of the longitudinal edges 25, 26 of the active element carrier 1, however, the first body rods 7 and the second body rods 8, 9 intersect with one another certain distance, so that in the region of the longitudinal edges 25, 26, the first carcass rods 7 and the second carcass rods 8, 9 each form a multi-finger arrangement. In the region of the longitudinal edge 26, the active element receptacle is supported on these multiple-finger arrangements.

The use of light metal body members to form the body 2 in skeleton construction allows the body 2 to be designed for high lateral bending stiffness, high transverse shear stiffness, and sufficiently high torsional rigidity. There is little longitudinal stiffness to avoid thermal expansion in the longitudinal direction. As a result, sound-emitting surfaces are kept small. You can choose in the attachment areas 20 an optimal shape for attaching the body 2 to levers or other machine elements. The individual length of a body element can correspond to the distance between two levers. The lightweight design allows good workability for functional surfaces and fasteners, such as threads. You can choose the bar distribution to match the power flow, for example, thicker on the lever attachments, where there is a force application, and thinner between the levers.

The active element receptacle 3 may be formed as an extruded plastic profile. This results in good machinability and low density. The length can be selected according to the length of the active element carrier.

The plastic rods 16-19 act on the one hand as a longitudinal reinforcement and also produce a very high flexural rigidity of the body 2. The ratio between the plastic rods 16-19 and the body rods 4-11 is suitably chosen so that the longitudinal stiffness of the body 2 to a very large Share is dominated by the plastic rods 16-19.

Fig. 4 shows a modified embodiment of an active element carrier 1. Here there are between the longitudinal edges 25, 26 of the active element carrier only body post 27, 28, which are arranged at an angle of about 60 ° to the longitudinal direction of the active element carrier. The angle may also be more generally in a range of 45 ° to 75 °, in particular 55 ° to 65 °. 60 ° are preferred.

In all embodiments, the body rods 7-9, 27, 28 may be formed of aluminum, which are held together in the longitudinal direction of the active element carrier 1 by the plastic rods 16-19. In the embodiment according to Fig. 4 results in a "concertina-like" training in which the carcass rods 27, 28 contribute little to the longitudinal stiffness. The longitudinal rigidity is achieved by the plastic rods 16-19.

All embodiments have a skeleton structure in which the size of sound-emitting surfaces is minimized. Even at higher working speeds, this results in a relatively low noise level.

Claims (14)

1. Knitting element bar (1) having a main body (2), which has a longitudinal direction (22), and a knitting element receptacle (3), characterized in that the main body (2) has a skeleton structure, which has a multiplicity of main body rods (4 - 11, 27, 28) which are interconnected at intersection points (12 - 15, 24).
2. Knitting element bar according to Claim 1, characterized in that fibre-reinforced plastic rods (16 - 19) which are connected to the skeleton structure run in the longitudinal direction (22).
3. Knitting element bar according to Claim 2, characterized in that at least one plastic rod (16 - 19) is configured so as to be continuous across the length of the knitting element support.
4. Knitting element bar according to Claim 2 or 3, characterized in that at least one plastic rod (16 - 19) in the longitudinal direction (22) has an interruption, wherein at least one other plastic rod bridges the interruption.
5. Knitting element bar according to one of Claims 1 to 4, characterized in that the skeleton structure has a light metal structure.
6. Knitting element bar according to one of Claims 1 to 5, characterized in that the main body (2) has a plurality of main body elements which are disposed beside one another and have main body rods and are interconnected.
7. Knitting element bar according to one of Claims 1 to 6, characterized in that the skeleton structure is configured in the manner of a polygon in a plane to which the longitudinal direction (22) is perpendicular.
8. Knitting element bar according to Claim 7 as far as this is related back to claims 2 to 6, characterized in that at least two plastic rods (16 - 19) are disposed on corners of the polygon.
9. Knitting element bar according to one of Claims 1 to 8, characterized in that the skeleton structure has main body rods (27, 28) which in relation to the longitudinal direction (22) run at an angle of 45° to 75°, in particular at an angle of 55° to 65°.
10. Knitting element bar according to one of Claims 1 to 9, characterized in that the skeleton structure has first main body rods (4 - 7) which run in a width direction (23) that is transverse to the longitudinal direction (22), and second main body rods (8 - 11) which in relation to the longitudinal direction (22) run at an angle in the range from 30° to 60°, in particular from 40° to 50°.
11. Knitting element bar according to Claim 10, characterized in that the skeleton structure has fastening regions (20) for machine elements, and a density of the second rods (8 - 11) in the region of the fastening regions (20) is higher than a density of the second rods (8 - 11) between the fastening regions (20).
12. Knitting element bar according to Claim 10 or 11, characterized in that the main body (2) has an upper side and a lower side, and the second main body rods are (8 - 11) disposed on the upper side and/or on the lower side.
13. Knitting element bar according to one of Claims 10 to 12, characterized in that the first main body rods (4 - 11) and the second main body rods (8 - 11) intersect in the region of at least one longitudinal edge (25, 26) of the main body (2) so as to be spaced apart from said longitudinal edge (25, 26), and form a multiple-finger arrangement.
14. Knitting element bar according to Claim 13, characterized in that the knitting element receptacle (3) is supported on the multiple-finger arrangement.

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