WO2004059056A1

WO2004059056A1 - Insertion device

Info

Publication number: WO2004059056A1
Application number: PCT/NL2003/000763
Authority: WO
Inventors: Joannes Josephus Henricus Marie Gorris
Original assignee: Te Strake Textile B.V.
Priority date: 2002-12-16
Filing date: 2003-11-04
Publication date: 2004-07-15
Also published as: CN1711380A; AU2003280891A1; NL1022173C2

Abstract

The invention relates to an insertion device for high-speed insertion of flexible yarns into a yarn-processing device, which insertion device comprises at least one insertion assembly, each insertion assembly being composed of: a housing provided with a through bore (12), an inlet member or insertion needle (6) accommodated in the bore (12), which is provided with a central channel for passing a yarn to be inserted, which central channel (7) ends into a mixing chamber (9) that forms part of the bore, a supply channel formed in the housing for supplying a medium under pressure, which supply channel (10) connects to the mixing chamber at evenly distributed positions around the insertion needle, as well as a yarn supply tube (4) connecting to the mixing chamber for supplying the yarn to the yarn-processing device. The object of the present invention is to provide to provide an insertion device, and more in particular a multiple insertion device, which not only has significantly reduced overall dimensions but also a low weight. According to the invention, the insertion device is characterized in that the insertion assembly is surrounded by an embedding envelope of a light, curable plastic.

Description

Insertion device.

DESCRIPTION

The invention relates to an insertion device for high-speed insertion of flexible yarns into a yarn-processing device, which insertion device comprises at least one insertion assembly, each insertion assembly being composed of: a housing provided with a through bore; an inlet member or insertion needle accommodated in the bore, which is provided with a central channel for passing a yarn to be inserted, which central channel ends into a mixing chamber that forms part of the bore; a supply channel formed in the housing for supplying a medium under pressure, which supply channel connects to the mixing chamber at evenly distributed positions around the insertion needle; as well as a yarn supply tube connecting to the mixing chamber for supplying the yarn to the yarn-processing device.

The invention furthermore relates to a method and a mould for manufacturing such an insertion device.

Such an insertion device is known, for example from Dutch patent No. 1004117 in the name of the present applicant. The current development in the yarn-processing devices, such as weaving machines, tends towards the use of insertion devices by means of which several yarns, up to as many as eight yarns, having different colours are introduced into the yarn-processing device. The use of several yarns having different colours requires the presence of several insertion assemblies - one for each yarn type and/or yarn colour - which, mounted on a chassis, form the insertion device. In an industrial application said assembled insertion device is mounted on the reciprocating entry side of the shed of the weaving machine in question.

Such multicolour insertion devices have considerable, increasing constructional dimensions, and consequently an increasing amount of space is required for building said devices into the weaving machine, which space is not always available, unless costly constructional measures are taken, such as modifying the weaving machine. In addition to that, the weight of such insertion devices continues to increase. In particular this latter aspect increasingly constitutes a limiting factor, since the increased weight leads to a higher mass inertia, as a consequence of which the insertion devices are less suitable for use in the current generation of weaving machines, which are operated at increasingly high speeds.

Accordingly it is an object of the present invention to provide an insertion device, and more in particular a multiple insertion device, which not only has significantly reduced overall dimensions but also a low weight. According to the invention, the insertion device is characterized in that the insertion assembly is surrounded by an embedding envelope of a light, curable plastic. More in particular, the insertion device comprises several insertion assemblies.

A considerable saving in weight can be achieved by surrounding the insertion assembly or assemblies with an embedding envelope of a light, curable plastic, because the insertion assembly or assemblies no longer need to be mounted on a chassis, which chassis constitutes a large part of the overall weight of the insertion devices that are currently known.

The plastic embedding envelope furthermore leads to an insertion device having limited constructional dimensions, which makes it possible to mount the insertion device in the weaving machine without any additional measures being required.

Especially the light construction makes it possible to use the insertion device according to the invention in high-speed weaving machines as well .

In a specific embodiment, each insertion assembly can be placed in a mould for the purpose of providing the plastic embedding envelope.

According to the invention, in order to obtain an adequate spatial connection between the various parts, each insertion assembly can be placed in the mould by means of at least one spacer.

More in particular, the insertion assemblies are to that end connected to each other and/or to the mould by means of several spacers.

In a specific embodiment, a spacer is embodied as a plate member provided with one or more openings for receiving the exit end of a yarn supply tube. The spacer may be made of a hard material, for example a ceramic material, in order to prevent friction grooves being formed by the yarn at the exit ends. The number of openings in the plate member may correspond to the number of insertion assemblies of the insertion device.

In another embodiment, the insertion device according to the invention is characterized in that flexible plastic hoses can be placed in the mould for forming internal channels in the embedding envelope, which internal channels connect to the supply channels for supplying medium under pressure.

According to the invention, a further significant weight reduction can be obtained if the insertion needle is made of a foil, preferably a metal foil.

The invention also relates to a mould suitable for manufacturing an insertion device according to the invention. The invention furthermore relates to a method for manufacturing an insertion device comprising at least one insertion assembly according to the invention, which method comprises the steps of: placing the insertion assembly in a mould; introducing a light, curable plastic embedding the insertion assembly into said mould.

The invention will be explained hereinafter with reference to the drawings, in which:

Figure 1 shows a multiple insertion device according to the prior art;

Figure 2 shows part of the insertion device of Figure 1;

Figure 3 shows an embodiment of an insertion device according to the present invention; and

Figure 4 shows an insertion device according to the present invention present in a mould according to the invention.

Figure 1 schematically shows an embodiment of an insertion device according to the prior art, more in particular a multiple insertion device comprising several insertion assemblies. The insertion device comprises a housing 1 accommodating a number of insertion assemblies. A number of yarn supply tubes 4 (eight in all) connect to the end face 3 of the housing 1, as do a number of hoses 5 for supplying a medium under pressure (e.g. compressed air). The housing 1, the block of supply hoses 5, as well as the yarn supply tubes 4 are mounted on a chassis 14-14a, which is in turn mounted on the entry side of the shed of the weaving machine.

Figure 2 is a sectional view of the housing 1. Said sectional view shows the housing being provided with a few through bores 12, each accommodating an insertion element. Each of said insertion elements comprises an insertion needle 6 provided with a central channel 7 for the passage therethrough of a yarn (not shown) to be transported. The insertion needle 6 extends with its downstream end 6a into one end of the mixing tube (indicated at 8), which is likewise accommodated in the bore 12.

The central channels 7 ends into the end face 2 of the housing 1 with its one end, whilst the mixing tube 8 and the yarn supply tube 4 connecting thereto connect to the end face 3 of the housing 1. The insertion needle 7 and the mixing tube 8 are held in position with respect to each other by the housing 1, which surrounds the two parts. The housing 1 bounds an annular mixing chamber 9 forming part of the bore 12, which surrounds the insertion needle 7.

A supply channel 10, which extends substantially parallel to the central axis of the central channel 7 and the mixing tube 8 in this known embodiment of the insertion device, connects to the mixing chamber 9. A medium under pressure, for example compressed air, can be supplied via said supply channel. As the Figure shows, the channel 10 substantially connects to a space 11 of the mixing chamber 9, which space 11 forms the connection between the chamber 9 and the mixing tube 8. The end 13 of the channel 10 connects to the end face 3 of the housing 1, and it will function as a connection for a flexible supply hose as shown in Figure 1.

The medium under pressure that is supplied through the channel 10 will flow in the direction of the space 11 and enter the mixing tube 8 via said space, carrying along a yarn present in the central channel 7 and onwards to and through the yarn supply tube 4. In this way differently coloured yarns can be blown or shot into the shed in succession in dependence on the adjusted weaving pattern by suitably controlling the various insertion assemblies by means of the medium under pressure.

A major drawback of insertion devices according to the prior art is the fact that an increasing number of insertion assemblies not only leads to increasing constructional dimensions, but above all to an increasing weight. The latter fact is inter alia caused by the chassis 14, which contributes in large measure to the weight of the overall insertion device. Said chassis 14 must be mounted on the moving part of the entry side of the shed of the weaving machine. An increasing weight of the known insertion devices causes the mass inertia to increase as well, which has a negative effect as regards the possibility to use multiple insertion devices in weaving machines. The increasing weight or mass inertia of the insertion device furthermore has a negative effect on the overall performance of weaving machines, which are currently being operated at increasingly high speeds.

Another drawback of the multiple insertion devices that are currently known is the fact that the insertion assemblies and the housing with the attached chassis are usually built into the weaving machine at a location where very little space is available for, for example, the connections of the supply channels for the pressurised medium. As a result, space must be reserved for connecting the supply channels for medium under pressure to the housing when building multiple insertion devices comprising large number of insertion assemblies into weaving machines. The constructional measures that have to be taken in this regard lead to additional cost.

The object of the insertion device according to the invention is to obviate these drawbacks. According to the invention, each individual insertion assembly, four insertion assemblies in Figure 3, is to that end surrounded by an embedding envelope 15 of a light, curable plastic. Parts that correspond to parts shown in the embodiment of Figures 1 and 2 are indicated by the same numerals as in Figures 1 and 2.

The advantages of this embodiment of an insertion device according to the invention will be apparent. The chassis 14-14a as shown in Figure 1, which contributes in large measure both to the spatial constructional dimensions and to the weight of the multiple insertion device can be left out altogether now. This leads to a significant weight reduction and also to a more compact construction than was previously possible.

The constructional connection between the various parts is now provided by a light plastic embedding envelope 15 which closely surrounds the various insertion assemblies. In particular this latter aspect leads to a compact insertion device, which enables easy mounting in the weaving machines without all kinds of constructional adaptations being required. As a result of the considerable weight reduction obtained by the light, plastic embedding envelope 15, the insertion device according to the invention is furthermore characterized by a low, more favourable mass inertia, which enables implementation thereof in new- generation weaving machines, which are operated at higher speeds. This latter aspect, too, provides constructional and economic advantages, as the constructional requirements that are made of the weaving machine may be less stringent as well.

Spacers 16, 18 may be used for effecting a correct spatial orientation of the various insertion assemblies with respect to each other, which spacers position the individual insertion assemblies a suitable distance apart and fix them in said positions before embedding the overall spatial construction in a light, curable plastic so as to obtain the embedding envelope 15.

The spacer 18 is made up of a plate member having bent-over edges 19, which plate member 18 is provided with openings in which the end 14b of each yarn supply tube 4 can be accommodated. Preferably, the spacer 18 has a number of openings equal to the number of yarn supply tubes 4 of the multiple insertion device to be constructed, with the openings being arranged an equal distance apart.

The spacer 16 in particular functions to orient supply hoses 5 for supplying medium under pressure and fix them in position, which supply hoses 5 each connect to a corresponding supply channel 10, which is in turn connected to the mixing chamber 9 in the housing 1.

Furthermore, a point of attachment 22 is provided in the plastic embedding envelope 15, which point of attachment enables easy fitting or mounting of the insertion device in the weaving machine.

A mould, such as the mould that is shown in Figure 4, is used for manufacturing a single or multiple insertion device according to the invention. The mould 21, which preferably has a simple, rectangular shape, is built up of a number of wall members 21a, 21b, 21c, 21d, 21e, which wall members form one integrated unit, or which can be assembled into a mould 21 by means of suitable connectors, such as screws.

On the other hand, the mould 21 may also be in one piece or be assembled from fewer (for example two) parts to be interconnected.

The mould 21 has an open space, in which the various components of the insertion device can be positioned by means of suitable spacers 16, 18.

The spacers 16, 18 are preferably embodied as plate members having bent-over edges provided with openings or screw holes that enable mounting thereof in one of the walls 21a-21e of the mould 21. Thus, the various components (insertion assemblies) can be connected to each other and/or to the mould by means of various spacers. The spacers thus ensure a correct spatial orientation of the insertion assemblies with respect to each other and with respect to the mould. The embedding envelope 15 can subsequently be provided around the various components in a simple manner by closing the mould with a sixth wall member (not shown) and filling the (now enclosed) open space in the mould containing the various components with a light, curable plastic. After curing, the various wall members of the mould 21 can be removed.

The multiple insertion device thus obtained is characterized by its compact dimensions and its low weight, which, as already said before, makes it possible to use the insertion device in high-speed weaving machines. The plastic embedding envelope 21 has a supporting function, so that a further weight reduction can be obtained by using a lighter construction of the various metal components of each insertion assembly. Think of the housing 1,8 in this connection, which may be stripped of all sorts of excess material. After all, the various components are kept together by the plastic embedding envelope 21.

An even further weight reduction can be obtained by forming the yarn supply tubes 4 from a thin metal foil, which may or may not be hardened, rather than using metal pipe members for this purpose. Thus, the metal components which come into contact with the flexible yarn to be passed through the insertion device in use can be made as light as possible. A thin layer of material, preferably a hardened metal, remains necessary so as to prevent friction grooves being formed in the plastic material of the embedding envelope 21 by the flexible yarn. It has become apparent, however, that a satisfactory operation is obtained if the yarn supply tubes 4 are made of a (hardened) metal foil, since the yarn supply tube 4 no longer needs to perform a supporting function. This latter function is now taken over by the plastic embedding envelope 1.

Consequently, the invention also relates to the mould as shown in Figure 4, as well as to a method for manufacturing an insertion device by using a mould according to the invention.

An even further weight reduction can be obtained by providing plastic hoses, which may or may not be flexible, between the housing 1, 8 and the spacer 18 instead of using the yarn supply tubes 4, which flexible hoses are removed or pulled from the plastic embedding envelope 15 that has been formed in the mould after said embedding envelope has cured. The channels in the plastic embedding envelope 15 that have thus been created can subsequently be coated with a suitable metal foil (for example by means of a vapour-depositing process), so that each yarn supply tube 4 no longer has a supporting function, but only functions to pass a weaving yarn therethrough. The applied thin metal foil layer only functions to prevent friction grooves being formed in the plastic material 15 by the yarn being passed. Likewise, flexible plastic hoses can be set up in the mould for forming internal channels 5 in the plastic embedding envelope 15, which internal channels function as supply channels for the medium to be supplied under pressure to the mixing chamber 9 in each housing 1.

Likewise, a spacer may be provided round the ends 4b of the yarn supply tubes 4, which spacer is made of a hard material, for example a ceramic material, to prevent friction grooves being formed in the ends 4b by the passing yarn.

Various materials, for example, various epoxy resins, thermoplastic or thermosetting materials, can suitably be used for embedding the insertion assembly of the insertion device. Likewise, various foaming plastics (polystyrene foam) may be used. Also combinations of the above materials are possible, for example in the form of a sandwich construction.

What is essential is the fact that the use of such plastics leads to a light insertion device having limited constructional dimensions, which on the one hand enables mounting thereof in a weaving machine, without additional measures being required, but which also enables the use thereof in high-speed yarn-processing devices, such as weaving machines.

Claims

1. An insertion device for high-speed insertion of flexible yarns into a yarn-processing device, which insertion device comprises at least one insertion assembly, each insertion assembly being composed of: a housing provided with a through bore; an inlet member or insertion needle accommodated in the bore, which is provided with a central channel for passing a yarn to be inserted, which central channel ends into a mixing chamber that forms part of the bore; a supply channel formed in the housing for supplying a medium under pressure, which supply channel connects to the mixing chamber at evenly distributed positions around the insertion needle; as well as a yarn supply tube connecting to the mixing chamber for supplying the yarn to the yarn-processing device, characterized in that said insertion assembly is surrounded by an embedding envelope of a light, curable plastic.

2. An insertion device according to claim 1, characterized in that the insertion device comprises several insertion assemblies.

3. An insertion device according to claim 1 or 2, characterized in that each insertion assembly can be placed in a mould for the purpose of providing the plastic embedding envelope.

4. An insertion device according to claim 3, characterized in that each insertion assembly can be placed in the mould by means of at least one spacer.

5. An insertion device according to claim 4, characterized in that the insertion assemblies are connected to each other and/or to the mould by means of several spacers.

6. An insertion device according to claim 4 or 5, characterized in that a spacer is embodied as a plate member provided with one or more openings for receiving the exit end of a yarn supply tube.

7. An insertion device according to claim 6, characterized in that said spacer is made of a hard material, for example a ceramic material, in order to prevent friction grooves being formed by the yarn at the exit ends.

8. An insertion device according to claim 6 or 7, characterized in that the number of openings in the plate member corresponds to the number of insertion assemblies of the insertion device.

9. An insertion device according to any one or more of the claims 3-8, characterized in that flexible plastic hoses can be placed in the mould for forming internal channels in the embedding envelope, which internal channels connect to the supply channels for supplying medium under pressure, which plastic hoses can be removed after curing of the embedding envelope.

10. An insertion device according to any one or more of the preceding claims, characterized in that the insertion needle is made of a foil, preferably a metal foil.

11. An insertion device according to any one or more of the preceding claims, characterized in that the yarn supply tube is made of a foil, preferably a metal foil.

12. A mould suitable for manufacturing an insertion device according to any one or more of the preceding claims.

13. A method for manufacturing an insertion device comprising at least one insertion assembly according to any one or more of the claims 1-11, which method comprises the steps of: placing the insertion assembly in a mould; introducing a light, curable plastic embedding the insertion assembly into said mould.