BAG OF TEXTILE MATERIAL PROVIDED WITH PIPINGS AND METHOD AND MACHINE FOR ITS MANUFACTURTNG
TECHNICAL FIELD The invention relates to a method and a machine for the manufacturing of a bag of textile material consisting of two single or multilayered sheets of fabric or other textile material, here denoted fabric sheets, which are sewn together with the on top of each other arranged fabric sheets having their back sides exposed, at the same time as a piping, here denoted cord, or other continuously formed inset, is sewn in in-between the fabric sheets along at least three of the side edges of the bag, when the fabric sheets have their back sides turned out and their right sides facing each other. The invention also relates to the bag manufactured according to the method and by the machine.
By fabric sheets it is here not only intended sheets of woven fabric but also tricot, felt and other textile materials, including composite materials.
PRIOR ART
From US-A-5,540,167 there is known a bag of the above described type and a method and device for the manufacturing of the same. According to that prior art technique, a first cord segment is arranged in-between a pair of first side edge sections along a first side edge of the two fabric sheets, so that a first edge of the first cord segment will face inwards and a second edge of the cord segment will be essentially in register with said first side edge. Thereafter, the first side edge sections of the two fabric sheets and a cord segment arranged in-between are sewn together by a first seam which extends along the entire length of the first side edge. Thereafter, an incision is made in one of the two fabric sheets in each end of the outer bottom edge of the bag, the length of each such incision essentially corresponding to the width of the first cord segment, whereafter a pair of cord segments are arranged in-between the fabric sheets, along the two side edges next to the first side edge in a similar manner as the first cord segment has been arranged along the first side edge but such that the additionally inserted cord segments are brought to protrude through the two incision openings adjacent the two corners in the bottom of the bag. Finally, the two other side edge sections together with cord segment arranged in-between are sewn together to form the bag as desired.
The described technique has the disadvantage that a through incisions are made in the fabric and that these incisions will be present in the final bag next to the inner corners of the bag, where they will constitute a potential risk for weakening of the construction.
Moreover, the performing of said incisions constitutes a complication in the manufac¬ turing, especially considering that they have to performed with a certain precision, at the same time as it complicates the equipment and require control and maintenance.
BRIEF ACCOUNT OF THE INVENTION
The objective of the invention is to provide a bag of the above described type which has at least equal - or better - properties than the bag according to said US 5,540,167 and to provide a method and a machine for manufacturing of the bag which are more simple and thereby better than the technique described in said patent, by the invention not requiring the making of any incisions in the fabric sheets to lead out the overlapping cord segments on the outside of the corners during the manufacturing, whereby there is not needed any maintenance demanding knives or other cutting means to make the incisions in the edge sections of the fabric sheets.
These and other objectives can be attained by that which is described in the appended claims.
Additional characteristics and aspects of the invention are clear from the description of a preferred embodiment of the invention.
BRIEF DESCRIPTION OF DRAWINGS
In the following description of a preferred embodiment, reference will be made to the appended drawing figures, of which:
Fig. 1 is a planar view which schematically illustrates a manufacturing line in a sewing machine for manufacturing of the bag according to the invention, Fig. 2A is showing in greater detail a, in Fig. 1 marked, section A of the side edge in the web shaped material which is to form bottom of the bag in series- production of bags,
Fig. 2B is showing a marked corner section B in Fig. 1 in greater detail,
Fig. 3 is showing a corner section C in Fig. 3 in greater detail, during a final phase of the manufacturing, Fig. 4 showing a corner section of the final bag, before a protruding cord section is cut and the bag is wrung, and
Fig. 5 is showing the same corner with an upper piece of fabric being cut off in the corner to illustrate how the cord segments are overlappingly arranged between the fabric sheets in the area of the corner.
DESCRIPTION OF A PREFERRED EMBODIMENT
A pair of web-shaped fabric materials 1' and 2', having the same width, are arranged on top of each other with the web 1' on top, on a transport line 3. The web-shaped materials 1' and 2' are arranged to be fed stepwise on the schematically illustrated material line 3 in the direction of the arrow 4. The arrow 4 is also schematically indicating the actuating means for the feeding in the direction of the arrow. A first cord 5 is arranged between the web materials V and 2'. along one longitudinal edge 6 of the materials, by aid of a feeding-in device 11 known per se. The cord 5 is of a known type and exhibits a thicker part 7, which is to form the visible part of the piping in the final bag, and a thinner part 8. The thicker part 7 exhibits a first edge 9 which is inwardly turned (forms an outer edge of the piping in the final, wrung bag) and a second edge 10 which will be essentially in register with said first side edge 6 of the two web materials 1' and , as is shown in Fig. 2 A.
The web materials 1' and 2' are sewn together by a first seam 12 in the area between the two edges 9, 10 of the cord 5, in parallel with the side edge 6. More specifically, the seam 12 is arranged adjacent the thickened part 9 of the cord. The sewing machine for making the seam 12 has been shown schematically by 13.
The first seam 12 is performed with certain interruptions, i.e. so that certain lengths are seamless. These lengths have an extension of 2L, Fig. 2A. The purpose of these shall be explained in the following. The end points of the thus formed first seams 12 have been denoted X and Y.
Bags are to be formed from the web materials 1' and 2 thus sewn together. In the next step of the manufacturing, a bag blank is accordingly cut off by a cut 15 across the entire width of the sewn together web materials, Fig. 2 A which is accomplished by aid of a cutting machine 16. The cut 15 is performed halfway between the adjacent end points X and Y of the first seams 12, Fig. 2 A, so that each corner, which is to form an inner corner of the bag, has a seamless section with the length L between the end points X and Y, respectively, of the first seam 12 and the side edges 18 and 19, respectively, of the thus cut off fabric sheets 1 and 2, next to said first side edge 6. The bag blanks 20, which are sewn together in the bag bottom to be, by the first seam 2 are now trans-
ported in the direction of the arrow 21 by actuating means symbolised by the same arrow 21. A second cord segment 22, of the same structure as the first cord segment 5, is now arranged in-between the fabric sheets 1 and 2 in the bag blank 20 in the area of a second pair of side edge sections along the second side edge 18, and a third cord seg- ment 23 of the same type is inserted in a corresponding manner between a third pair of side edge sections along the third side edge of the two fabric sheets 1 and 2. The thus, by the insertions 30 and 31 inserted cord segments 22 and 23, as well as the cord segment 22 which is inserted in the manner shown in Fig. 3, are now sewn in place between the fabric sheets 1 and 2 in the same way as the first cord segment 5 was sewn in place along the first side edge 6. The thus formed second and third seams have been denoted 24 and 25, respectively, and the sewing machines for accomplishing these seams have been denoted 26 and 27 respectively, in Fig. 1. At the same time, the edge sections are trimmed in a manner known per se, so that the final side edge 18' becomes even and tidy. The cut away edge material has been denoted 29.
The insertion of cord segments 22 and 23 between the fabric sheets 1 and 2 continues beyond the end points X and Y of the first seam 12 and beyond the first side edge 6. Thus, the cord segments 22 and 23, as well as the cord segment 22, Fig. 3, are arranged such that the inner edge 9 of the thicker part 7 is brought to abut the end of the seam 12 in the points X and Y and such that the cord segments 22 are brought to overlap and directly abut the first cord segment 5, Fig. 5, in the area of the corners of the bag, whereafter the seams 24 and 25 are fulfilled all the way out to the first side edge 6, and even a distance beyond the same, but here only in a protruding cord section, such as cord section 22' in Fig. 4.
As to be understood by the description above, the sections L have a length which corresponds to the width of the cord 22 and 23 in the final bag plus the width of the edge material 29 which optionally is cut off in the trimming of the edges.
In connection with the making of the seams 12, 24 and 25, these are also overcast by over-lock seams denoted 30 and 31. Finally, the protruding cord sections, such as section 22', are cut off before the bag is wrung. In the final, wrung bag, the corners with their visible parts of cords/pipings have the same outer appearance as the bag described in above mentioned US-A-5,540,160.