Technical field

The invention relates to a weaving machine system for pulling binding warp yarns out of a shed into a gap between upper and lower outer fabrics of a distance fabric during formation of loops of the binding yarns by means of a manipulating bar, coupleable to at least two electromagnets arranged reversibly displaceably above the upper outer fabric in the direction of the distance fabric take-up motion and back.

Background art

Distance fabrics contain two outer fabrics and a plurality of binding yarns connected to the outer fabrics and arranged between them.

US 8 015 999 B2 describes a method for forming this type of a distant fabric in which the distance fabric is formed on a weaving machine from two systems of warp yarns, whereby the system of basic warp yarns only serves to weave the two outer fabrics and the system of binding warp yarns serves to weave the two outer fabrics and, during the interruption of weaving, it is used to create the binding yarns by pulling the binding warp yarns out of a shed into a gap between the outer fabrics by means of a pulling means of the binding warp yarns.

Pulling the binding warp yarns out of the shed is carried out manually during the interruption of weaving, when, after crossing the binding warp yarns, one operator inserts a pulling bar into the shed from one side. The pulling bar is then gripped by a second operator and both operators pull the pulling bar towards themselves, while a third operator releases the binding warp yarns.

The aim of the invention is to provide a weaving machine system for pulling binding warp yarns out of a shed into a gap between the upper outer fabric and the lower outer fabric of a distance fabric during formation of loops of binding yarns in this gap. Principle of the invention

The aim of the invention is achieved by a weaving machine system whose principle consists in that a manipulating bar is in places in which it is coupleable to electromagnets provided with permanent magnets arranged in a Halbach array, whereby the electromagnets are provided at the bottom with non-magnetic material sliding parts in which the pole pieces of the respective electromagnet terminate.

Due to the length of the manipulating bar, a lightweight, high stiffness material is suitable for its production, such as a carbon composite or titanium or hard anodized duralumin.

In order to facilitate the production of the manipulating bar, it is advantageous if the bar comprises, in its central part, a support core of a lightweight, high stiffness material, to which end pieces are attached at the edges.

The core can be made of a carbon composite or titanium or hard anodized duralumin or another suitable material.

To strengthen the manipulating bar and reduce wear, at least a part of the manipulating bar is overlapped with cover plates of a high strength material selected from the group consisting of stainless steels.

In a preferred embodiment, the entire manipulating bar is overlapped with a high strength material.

For the cooperation with the electromagnets, it is advantageous if the permanent magnets arranged in Halbach arrays are situated at the ends of the manipulating bar, preferably in the end pieces of the manipulating bar.

The Halbach arrays of permanent magnets are formed by rows of at least five permanent magnets which are arranged perpendicular to the length of the manipulating bar and the Halbach arrays are arranged in the shed with their strong side upward against the corresponding electromagnets.

In order to obtain optimal forces for holding and transferring the manipulating bar, the pole pieces of the electromagnets are terminated with working parts which extend into the sliding part of the electromagnet in its front part.

The above-mentioned working parts of the pole pieces of the electromagnets are arranged in a direction perpendicular to the rows of permanent magnets arranged in the Halbach arrays.

To make the system more reliable, a manipulating bar loss sensor is arranged in each electromagnet.

Description of the drawings

An exemplary embodiment of the weaving machine system according to the invention is schematically represented in the drawings, wherein Fig. 1 is a schematic diagram of the weaving machine mechanism with the manipulating bar in the shed, Fig. 2 is a schematic diagram of the weaving machine with the manipulating bar in the gap between the outer fabrics, Fig. 3 is a view of the manipulating bar without cover plates, Fig. 4 is a view of the manipulating bar overlapped with cover plates, Fig. 5 shows an arrangement of the permanent magnets in the Flalbach array, Fig. 6 shows a cross-sectional view of an electromagnet, Fig. 7 is a view of an electromagnet without a winding and Fig. 8 is view of an electromagnet without a right-hand side cover.

Examples of embodiment

The weaving machine system for pulling binding warp yarns 2 out of a shed P into a gap TO between an upper outer fabric T1 and a lower outer fabric T2 of a distance fabric T during formation of loops of binding yarns by means of a manipulating bar 4 coupleable to at least two electromagnets 5 arranged above the upper outer fabric T1 reversibly displaceably in the direction of the take-up motion of the distance fabric T and back will be briefly described with reference to schematic diagrams of the weaving machine mechanisms showing the manipulating bar 4 inserted into the shed P (Fig. 1 ) and captured by the electromagnets 5 and in the next step during the pulling of the binding warp yarns 2 into the gap TO between the outer fabrics T1 and T2 (Fig. 2). The number of the electromagnets 5 may be even higher, for example, three or four, two of them being disposed at the edges and the remaining electromagnet/electromagnets in the central part, whereby the manipulating bar 4 is at the respective points provided with permanent magnets 44 arranged in Halbach arrays 440.

The distance fabric T is formed from two warp systems, whereby the system of ground warp yarns 1 only serves to weave the two outer fabrics T1 , T2 and the system of the binding warp yarns 2 serves to weave the two outer fabrics T1 , T2 and, during the interruption of the weaving process, to form loops of binding yarns 200 by pulling the binding warp yarns 2 out of the shed P into the gap TO between the outer fabrics T1 , T2. Both warp yarns systems 1 , 2 pass in a known manner through heald shafts L and through a reed 31 of a beating-up mechanism 3.

Fig. 1 shows the manipulating bar 4 in the shed P held by the electromagnets 5 after crossing the binding warp yarns 2 before the insertion of the bar 4 into the shed. In doing so, a part of the upper outer fabric T1 is clamped between the electromagnet 5 and the bar 4. In the next step, the manipulating bar 4, still held by the electromagnets 5, is moved in the direction of the take-up motion of the distance fabric T by a specified distance and, at the same time, the manipulating bar 4 pulls the loops of the binding warp yarns 2 into the gap between the outer fabrics T1 , T2, whereby the binding warp yarns 2 are synchronously released from the respective warp beam.

In an exemplary embodiment of Figs. 3 and 4, the manipulating bar 4 comprises a supporting core 41 made of a lightweight, high stiffness material, in an exemplary embodiment made of a carbon composite, which guarantees sufficient stiffness even at lengths greater than 1 ,500 mm. The supporting core 41 may also be made of another suitable material, such as titanium or hard anodized duralumin. At the ends, end pieces 42, 43 are attached to the supporting core 41 , in which permanent magnets 44 are mounted, arranged in the Flalbach arrays 440. The end pieces 42, 43 are different from each other - a manipulating end piece 42 is facing on the side an unillustrated device of inserting the manipulating bar 4 into the shed P and pulling it out of the shed P, and a sliding end piece 43 is on the opposite side. Fixing holes 45 are formed in the manipulating bar 4 to provide for precise positioning of the bar 4 when manipulating it during the interruption of the weaving process, especially after returning the bar to the shed prior to pulling it out of the shed P and after the bar is reinserted into the shed P before being held by the electromagnets.

The Halbach arrays 440 of permanent magnets 44 are formed by rows of at least five cube-shaped magnets, as shown in the illustrated embodiment, whereby the rows are oriented in a direction perpendicular to the length of the manipulating bar 4 and the Halbach arrays are arranged with their strong side upward against the electromagnets 5. In a specific embodiment shown, nine Halbach arrays 440 are used, each consisting of five permanent magnets 44. The permanent magnets 44 in the individual Halbach arrays are glued to each other and the individual rows of the Halbach arrays are glued into holes formed in the respective end piece 42, 43 of the manipulating bar 4.

The manipulating end piece 42 of the manipulating bar 4 comprises a recess 421 at its free end 420 for gripping an insertion mechanism by manipulating tweezers. The front edge 4211 of the recess 421 is used as a sensing edge for a manipulating bar 4 loss sensor 56 disposed on the respective electromagnet 5.

The sliding end piece 43 is rounded at the edges to reduce the risk of yarn getting caught and a hole 431 is formed in the sliding end piece 43 at its free end 430, the front edge 4311 of the hole 431 is used as a sensing edge for the manipulating bar 4 loss sensor 56 disposed on the respective electromagnet 5.

In an unillustrated embodiment, the manipulating bar 4 can be made of one piece, wherein the permanent magnets 44 are mounted at the ends of the bar 4. In this embodiment, too, the end pieces at the free ends of the manipulating bar 4 are identical as or similar to the free ends 420, 430 of the end pieces 42, 43.

In order to increase the strength and durability, the manipulating bar 4, at least on a part of its length in contact with the binding warp yarns 2, is overlapped with cover plates 40 from high strength material, such as high strength stainless steel. In an embodiment according to Fig. 4, the manipulating bar 4 is overlapped along its entire length as far as to the free ends 420, 430. Thus, a smooth, strong and durable coating is formed on the manipulating bar 4 surface which comes into contact with the yarns.

The electromagnets 5 are formed by a core 51 , around which a winding 52 is arranged, constituting a coil. A lower pole piece 53 and an upper pole piece 54 are disposed on the core 51. The lower pole piece 53 is embedded in a non-magnetic sliding part 55, which is provided with a smooth finish allowing the sliding part 55 to slide smoothly over the upper outer fabric T1 and the warp yarns 1. In the front part of the sliding part 55, the lower pole piece 53 is terminated by a working part 531. Attached to the upper pole piece 54 is a front part 540 of the upper pole piece 54 terminated in the sliding part 55 by a working part 541 which is arranged in the vicinity of the rear working part 531 of the lower pole piece 53 and is parallel to it, whereby the shape of the sliding part 55 and the working parts 531 and 541 of the pole pieces 53, 54 is adapted to achieve the shortest possible loop of the binding warp yarns 2 when they are pulled out of the shed P and at the same time to develop the maximum working force on the manipulating bar 4. In the electromagnet 5 is arranged a manipulating bar 4 loss sensor 56 in both directions of its motion, which is connected to means of a control system of the weaving machine. In a specific exemplary embodiment, the sensor 56 is formed by an inductive sensor with optical signalling and a sensor 56 of the right electromagnet 5 monitors the position of the front edge 4211 of the recess 421 for the manipulating tweezers in the free end 420 of the manipulating end piece 42 of the manipulating bar 4 and the sensor of the left electromagnet 5 monitors the position of the front edge 431 1 of the hole 431 in the free end 430 of the sliding end piece 43 of the manipulating bar 4. The electromagnets 5 are provided with covers 57 from the rear and lateral sides.

The dimensions and spacing of the working parts 531 of the lower pole piece 53 and the working parts 541 of the upper pole piece 54 are linked to the dimensions of the permanent magnets 44 in the manipulating bar 4 arranged in the Halbach arrays 440. In an exemplary embodiment, the width of the working parts 531 , 541 equals the length of the side of the permanent magnet 44 and the distance between the working parts 531 and 541 also equals the length of the side of the permanent magnet 44. The length of the working parts 531 and 541 of the pole pieces 53, 54 is equal to or less than the length of the Halbach arrays 440, i.e. the adjacent rows of permanent magnets 44 arranged in the Halbach arrays. The number of permanent magnets 5 may be even higher, for example, three or four, two being arranged at the edges and the remaining in the central part, whereby the manipulating bar 4 is at the respective points provided with permanent magnets 44 arranged in Halbach arrays 440.

The number of permanent magnets 44 in the Halbach array is given by 4n+1 , therefore the minimum number is five.

Industrial applicability

The invention is applicable in weaving machines manufacturing distance fabrics, wherein a system for pulling binding warp yarns out of a shed into a gap between the upper outer fabric and the lower outer fabric is formed duration formation of loops of binding yarns.

List of references

P shed

T distance fabric

T1 upper outer fabric

T2 lower outer fabric

TO gap between upper outer fabric and lower outer fabric L heald shafts

1 system of ground warp yarns

2 system of binding warp yarns

3 beating-up mechanism

31 reed

4 manipulating bar

40 coating of manipulating bar

41 supporting core of manipulating bar

42 manipulating end piece of manipulating bar

420 free end of manipulating end piece

421 recess for manipulating tweezers

421 1 front edge of recess

43 sliding end piece of manipulating bar

430 free end of sliding end piece

431 hole in free end of sliding end piece

431 1 front edge of hole

44 permanent magnets

440 Halbach array of permanent magnets

45 fixing holes

5 electromagnets

51 core of electromagnet

52 winding of electromagnet

53 lower pole piece

531 working part of lower pole piece

54 upper pole piece

540 working part of upper pole piece

541 front working part of upper pole piece

55 sliding part of electromagnet

56 manipulating bar loss sensor

57 cover