This invention relates to a method of preparing ribbed ticks comprising a textile top sheet and a textile bottom sheet which are connected at their edges, and partition walls which at their longitudinal edges are welded to the top sheet and bottom sheet, respectively, to form ducts in the tick, in which method partition walls folded about a longitudinal central line and covered at their outer sides along their longitudinal edges with a heat-sensitive binding material, are introduced between the top and bottom sheets, and the binding material is heated to melt and after cooling connects the partition wall to the top sheet and bottom sheet, respectively, whereafter, if necessary, these are cut into suitable lengths and connected along their edges.

A known method of the above-mentioned kind is described in the DK Patent Specifications Nos. 132,517 and 134,384. In this known method two webs of textile material are used as the top and bottom sheets, and said webs are conveyed at the same time while parallel coherent partition- wall strips are introduced between the two webs in a number corresponding to the desired number of ducts in the finished tick. Thereafter, the web product thus formed is heated in the zones corresponding to the introduced partition-wall strips and after cooling the product formed is cut into suitable lengths. Finally, the two webs of textile material are connected along their edges, e.g. by sewing. During practical production of ribbed ticks according to the described method it has appeared that the melted thermoplastic binding material penetrates the partition- wall strips so that the overlapping portions of the strips are not only bound to the two webs of textile material but are also bound together.

Consequently, it has been necessary to use unfolded partition-wall strips and to place coatings of a thermo-

plastic binding material at each side edge and at opposite sides of each strip. This means that the upper and lower webs of textile material must be placed laterally offset until the textile upper sheet and bottom sheet are to be sewn together.

The known method is not usable in the production of partition walls either, which extend obliquely to or both lengthwise and crosswise of the machine direction, so that it is impossible to obtain any desired placing of the partition walls and, consequently, a desired stabilization of the insulating material, e.g. in the form of down and/or feathers, to be introduced in the ribbed tick.

These drawbacks are eliminated by the method according to the invention, said method being characteristic in that lengths of the folded partition-wall strips with outer edge zones covered with binding material are provided with a strip-shaped barrier placed therebetween and adapted to prevent melted binding material from the two zones from flowing together, said strip-shaped barrier being placed in a desired pattern between the top and bottom sheets before these are heated simultaneously from both sides.

By using, instead of coherent partition-wall strips, lengths thereof and by heating the entire surface simultaneously it becomes possible to place folded partition- wall strips in any desired pattern. This is preferably done by stepwise carrying a lower length of textile material on to a light table showing the desired placing pattern and by manually placing the lengths of partition-wall strips in the shown pattern and, thereafter, placing an upper length of textile material on the lower one before the two lengths are carried through a heating apparatus capable of heating the joint in a zone extending from one side edge of the joint to the other.

The strip-shaped barrier between the two overlapping portions of the partition-wall strips effectively prevent these from melting together and it is therefore possible to

sew the edges of the textile lengths together without it being necessary to move one of them relative to the other.

An example of a suitable barrier material is cotton, preferably in the shape of two ribbons which are placed at the inner side of the folded partition wall within each binder-coated edge zone. In connection with binders activated at a relatively low temperature, teflon or a corresponding material may be used as well, preferably in the shape of film strips connected with one of the overlapping portions of the partition-wall strip and preventing penetration of melted binding material.

It is particularly expedient to fasten the ribbons forming the strip-shaped barrier to the partition-wall strips by point-thermofixation. Moreover, the invention concerns an apparatus for carrying out the method described above. This apparatus is characteristic in that it comprises means for conveying a web of textile material upon which partition-wall strips are placed as described above in a desired pattern, means for placing a second web of textile material upon said first web of textile material, and means for heating all parts of the joint of textile webs and partition-wall strips placed therebetween.

In the following the invention is described in details with reference to the drawing, where

Figure 1 shows a perspective view of a partition- wall strip to be used in the method according to the invention,

Figure 2 a sectioned view of the folded partition- wall strip according to Figure 1,

Figures 3 to 5 three different placing patterns for lengths of partition-wall strips to be used in the method according to the invention,

Figures 6 and 7 a perspective resp. sectioned view of a second embodiment of a partition-wall strip to be used in the method according to the invention,

Figure 8 a schematic side view of an apparatus for carrying out the method according to the invention.

Figure 9 a schematic plan view of the apparatus according to Figure 6, and Figure 10 a detailed view of gripping members forming part of the apparatus shown in Figures 8 and 9.

Figures 1 and 2 show a partition-wall strip 1 which is folded about the longitudinal axis 2 thereof to form a half 3 overlapping another half 4. At their outer sides along an edge zone thereof, the halves 3 and 4 a covered with a heat activated binding material in the shape of fastened film strips 5 and 6 of a thermoplastic material. The film strips are fastened to the parts 3 and 4 of the partition-wall strip in points 7. In the embodiment according to Figures 1 and 2, a strip-shaped barrier placed between the strip portions 3 and 4 consists of two cotton ribbons 8 ensuring that the strip is allowed to be provided from both sides with heat sufficient to activate the binding material (the film strips 5 and 6) - and thus to fasten the partition wall to the top and bottom sheets - without heat from one of these heating systems spreading to the other to such a degree that melt from one edge zone penetrates into the other zone and binds the two halves 3 and 4 of the partition wall together. In the embodiment according to Figures 6 and 7, the barrier between the two halves 3 and 4 of the partition wall consists of a ribbon 8' of a material, such as teflon, which prevents melted material formed by heating of the film strips 5 and 6 and penetrating the adjacent strip portion, from contacting the opposite portion. The strip 8 ¹ is preferably fastened to one strip portion by spot welding. This barrier - possibly in the shape of two ribbons 8' - is applicable if the binding material is activated at a relatively low temperature, or if the material in the partition wall is less liable to be penetrated by binding material.

Figures 3 to 5 show preferred placing patterns for folded strip portions 1 placed at a web 9 of textile material.

The apparatus shown in Figures 8 and 9 consists of a mounting table 20 and a welding table 21. The mounting table 20 comprises a number of beam-shaped elements 22 (cf. Figure 8) placed at a short distance from each other and supported by a rest 23. At the left end thereof, the mounting table 20 is made as a light table 24 so constructed that given patterns are allowed to appear at the top of the light table. Placed at a short distance above the beam-shaped elements 22 a supporting plate 25 for a web of textile material is provided. A set of gripping members 26 is located under the supporting plate 25. As shown in Figure 10, the gripping members 26 comprise a frame 30 which is connected to a carrier plate 31 reciprocating on guides 32 mounted at beams 33 which are located at both sides of the mouting table 20. The movement of the carrier plate 31 is controlled by a V- belt carried around a pulley 35 which is connected to a motor not shown. At the lower beam 36 of the frame, in the spaces between the beam-shaped elements 22, bar-shaped stopping devices 37 are located, which cooperate with clamping means 38 placed on the upper beam 39 of the frame 30 in a way so as to be moved automatically in vertical direction by means of moving members not shown.

Placed above the supporting plate 25, brackets 40 are provided at the sides of the table, said brackets being connected to each other by a crossbeam 41 to which a pivoting arm 42 is secured, which carries an apparatus 43 cutting predetermined lenghts of a partition-wall strip introduced into the apparatus 43 from a roller 44 and over rollers 45.

The welding table 21 consists of a table top 50 placed at a rest 51. In the table top 50 a plate-shaped heating element 52 is mounted, which extends across the table top 50. A heating shoe 53 movable in vertical direction and extending across the width of the table 50 is mounted above the heating

element 52 together with an extractor screen 54 comprising a suction tube 55, said screen and tube being connected with a suction apparatus not shown.

In the immediate vicinity of the table top 50 gripping members 56 are mounted, which are adapted to grip and hold two webs of textile material placed on top of each other, and to stepwise convey said webs towards the opposite end of the welding table 21.

The mode of operation of the apparatus is described in the following.

The edges of a web 60 of textile material, which is placed at the supporting plate 25, and another web 61 of textile material, a part of which lies over the light table 24 and the opposite end of which is hanging down along the end of the mounting table 20, are introduced into the area between the stopping devices 37 and the movable clamping means 38 which are then made to hold the textile webs firmly therebetween.

Partition-wall strips are now placed in the pattern shown on the light table 24.

The gripping members 26 are then conveyed by one step towards the opposite end of the mounting table 20 whereafter a new section of the textile web 61 is carried on to the light table 24. Other partition-wall strips are now placed at the textile web 61, and the textile webs 60 and 61 are conveyed by another step.

These operations are repeated until partition-wall strips are placed all over the surface of the textile web 61, and the textile web 61 has been covered by the web 60. Thereafter, the gripping members 62 are released and carried back a short distance. Then again, they are made to firmly hold the textile webs between them, and said webs are now conveyed so far that the foremost edge is introduced into the gripping members 56 which are made to grip the material. After this, the gripping members 26 are carried back to

their starting position.

A stepwise conveyance of the two textile webs is now made by means of the gripping members 56 whereby between each step of conveyance a welding of the partition-wall strips to the two textile webs 60 and 61 is produced by the heating shoe 53 being lowered and made to press the textile webs 60 and 61 together in the area between the heating element 52 and the heating shoe 53.

When all parts of the two textile webs 60 and 61 have been heated as described, the gripping members 56 are carried back to their starting position, and the edges of the two textile webs 60 and 61 are sewn together.