Field of the Invention

The present invention concerns a method for producing fibre fill for use as filling material in clothing, sleeping bags, pillows and duvets and of the kind indicated in claim 1.

Background of the Invention

Prior art filling of polymeric fibres or filaments which are either solid or made as very thin tubular fibres or filaments have a tendency of becoming flat, i.e. after blowing into clothing, sleeping bags, pillows or duvets, the fibres or filaments do not retain their volume but collapse into incoherent flat pieces which are experienced as products with reduced volume.

Object of the Invention

On that background it is the object of the invention to indicate a method for making an improved filling material for use in blowing into duvets and pillows, and which appears as a much improved filling material which will keep returning to its original state at the blowing.

Description of the Invention

The method according to the invention is peculiar in that the fibre rope is divided into fibre bundles or fibre cords with a relatively large number of fibres or filaments of the magnitude 200-2000 pes, and then passing a gluing or welding unit, e.g. an ultrasound welding head, performing a punctiform gluing or welding together of the filaments spaced apart about 6-20 mm, the bundles subsequently passing a cutter or scissors which e.g. is controlled synchronously with the welding head and which shortens the filaments into lengths of about 6-20 mm, after which the shortened fibre down is either packed in shipping bales or are used directly for blowing into pillows or duvets as filling.

Surprisingly it has appeared that the thus produced polymeric, artificial fibre down appears as a very improved filling material which is capable of continuously maintaining a good filling capability and continuously returning to its original condition at the blowing.

The method according to the invention is suitably executed in such a way that tubular filaments or fibres with 1-9 holes and with a fibre thickness of 0.9 - 30 dtx are used, preferably about 0.9 - 7 dtx.

Alternatively, the method according to the invention can be executed in such a way that solid filaments or fibres with a fibre thickness of 0.9 - 30 dtx are used, preferably about 0.9 - 7 dtx.

Description of the Drawing

The invention is explained more closely in the following with reference to the drawing, on which: Fig. 1 shows a sketch of an embodiment of a very simplified facility according to the invention for opening/spreading polymeric fibres or filaments;

Fig. 2 shows a view of an embodiment of a comb with a number of twisted tubes having internal grooves;

Fig. 3 shows a much enlarged view of some finished fibre down; and

Fig. 4 shows a system of curving rods for spreading out fibre rope to bundles of fibres with e.g. 200-2000 fibres or filaments. Detailed Description of Embodiments of the Invention

Fig. 1 shows a much simplified facility 2 for making polymeric fibre down from a fibre rope 3 which is supplied in a cardboard packing containing about 40 kg of a fibre rope 3 with 30,000 - 80,000 fibres or filaments with a thickness of 0.9 - 30 dtx.

By means of pulling rollers 4 at the left side of Fig. 1 , the fibre rope 3 is drawn up from the cardboard packing and moved over a system of curving rods 6 (Fig. 4) with the intention of spreading out the fibre rope 3 in fan shape to a wide fibre cloth 8 (Fig. 4) which via rollers 10 is moved to a comb 12 with a large number of teeth 14 (of which only four are shown in Fig. 2).

The teeth 14 divide the fibre cloth 8 into fibre bundles, each containing, for example, 200-2000 fibres which are gathered in a circular tube 16 tapering from an inlet opening 13 and running twistedly towards an outlet 15 with a diameter of about 1 mm.

It is to be mentioned that the shown circular tubes 16 alternatively can have any desired cross-sectional shape - four-edged or polygonal.

In other words, the shown embodiment for a comb 12 is connected with the circular tubes 16 which in the direction of movement of the fibre rope 3 have a length of about 50-70 mm and which have a decreasing diameter and an internal groove towards the outlet 15 so that the fibre rope 3 leaves the circular tube 16 as a very thin intertwined fibre rope 3.

The shown insertion openings 13 are funnel-shaped and twisted, i.e. the fibre rope 3 is immediately compressed before being further intertwined - e.g. with 3-4 twists per centimetre - at the passage through the grooves of the circular tube towards the central outlet 15.

The twisted fibre bundles are moved from the outlet 15 as a fibre cord through a gluing or spot welding unit 18, e.g. an ultrasound welding unit, by which a punctiform bonding or welding is performed on each fibre bundle with a spacing of about 6 - 20 mm.

Afterwards, the cords or fibre bundles pass through a cutting unit 20 (knife or scissors) which cuts the fibre bundles into lengths of about 6-20 mm into actual fibre down 22, which is shown e.g. on Fig. 3.

The fibre down 22 formed thereby will still be gathered in a tight shape, which subsequently will entail that the fibre down 22 by blowing into duvets or pillows afterwards, at the earliest, will "open up" and get its final shape which is very like natural down because the punctiform welds are similar to the pointed end of the down. The fibre down 22 thus produced can either be packed into shipping bales or be used for directly blowing into duvets or pillows where the "opening up" itself of the fibre down occurs in connection with the blowing; in other words, the produced polymeric fibre down 22 will have appreciably less volume until it "experiences" a blowing operation for the first time, after which the fibre down 22 is provided a larger volume corresponding to natural down.

Decitex is actually an indication of fibre thickness (titer) as dtx is the weight in grams of a fibre or filament of 10,000 metres, i.e. 9 dtx means that 10,000 metres of fibre weighs 9 grams.