Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05C11/00—Component parts, details or accessories not specifically provided for in groups B05C1/00 - B05C9/00
  • B05C11/10—Storage, supply or control of liquid or other fluent material; Recovery of excess liquid or other fluent material
  • B05C11/1002—Means for controlling supply, i.e. flow or pressure, of liquid or other fluent material to the applying apparatus, e.g. valves
  • B05C11/1034—Means for controlling supply, i.e. flow or pressure, of liquid or other fluent material to the applying apparatus, e.g. valves specially designed for conducting intermittent application of small quantities, e.g. drops, of coating material
• • D—TEXTILES; PAPER
  • D05—SEWING; EMBROIDERING; TUFTING
  • D05B—SEWING
  • D05B17/00—Sewing machines for concurrently making thread and welded seams

Definitions

• This invention relates to sewing methods and machines, and more specifically to novel sewing method and machines in which threads are bonded to fabrics or to other threads, or the engagement of interlocking threads is strengthened, by means of adhesives, whereby to substitute or improve conventional sewing method and machines.
• a sewing machine which comprises adhesive means, constituted by thermoplastic or thermosetting synthetic bonding material, for bonding a thread into fixed positioned relationship with the fabric stock to be sewn.
• the sewing machine comprises, in combination with an upper thread bobbin and means for forming loops of said thread, as in conventional lock-stitch sewing machines, means for bringing a lower thread into contact with said loops, and means for bonding it in fixed positioned relationship to the fabric stock by bonding it to the underside of the fabric stock or to the -2-
• the invention generally, provides a sewing method which comprises bonding sewing threads to themselves or to one another, or bonding fabric layers together, by the use of an adhesive having a high elasticity.
• the elasticity of the bonding adhesive is preferably measured by its elongation at break, which must be at least 10-20% or higher, for instance, from 50 to 150%.A test for measuring the elongation at break of the adhesive will be described hereinafter, and the values of said elongation, as set forth in this specification and claims, are understood to be determined by said test.
• a Chain-Stitch is locked, at the points of interlocking of successive loops of its single or double thread, with a bonding adhesive.
• the resulting stitch becomes stabilized and cannot unravel as the ordinary Chain-Stitch, and in fact behaves like a Lock-Stitch, so that it could be called "pseudo Lock-Stitch".
• stitching is carried out by means of a single thread that is passed through the fabric from one side and bonded on the other side of the fabric by means of a bonding adhesive, having the elasticity hereinbefore defined.
• an upper or lower thread may be used and be bonded to the fabric at its other side.
• stitching is carried out by means of two threads, one of which that is passed through the fabric from one side and bonded, without interlocking, on the other side of the fabric to the other thread, by means of a bonding adhesive, having the elasticity hereinbefore defined.
• fabrics are bonded without the use of threads, by means of a bonding adhesive, having the elasticity hereinbefore defined.
• the elongation at break of the bonding adhesive, according to the invention, is measured by the following test.
• a thread having a diameter of 1 mm. is -4-
• polymeric adhesives useful for carrying the invention into practice are any adhesives that can be formed by curing a precursor by means of UV light. Acrylate based adhesives are an example, but chemically different polymeric adhesives are known to persons skilled in the art.
• the bonding adhesive is applied by injecting a precursor, which is monomeric or oligomeric, polymerizable substance, in a fluid state, at the point where the adhesive bond is to be produced, each injection lasting for a very short time, in the order of thousands of a second, and then polymerizing the same, preferably by irradiation with UV light.
• the UV light may be produced by laser or by another source.
• the appropriate wavelength of the UV light can be determined by skilled persons depending on the type of polymer precursor and polymer to be obtained therefrom. In any case, the suppliers of the polymer precursor will furnish the necessary information to whoever carries this invention into practice.
• the injection and polymerization must be carried out under such conditions that the polymerizing radiation will not impinge on the monomeric or oligomeric adhesive precursor before or at the time of its injection. This can -5-
• the injection nozzle, on the one hand, and the source of polymerizing radiation, on the other, are spatially separated to such an extent that any mutual influence is prevented, and the precursor, injected at one point, is then shifted to the point on which the polymerizing radiation impinges.
• the direction of the injection (injection axis) and the direction of the radiation (radiation axis) form an angle, so that the radiation impinges on the polymer adhesive precursor only at the intersection of the two axes, which is the point at which the adhesive bond must be formed.
• Fig. 1 schematically illustrates a prior art Lock -Stitch
• Fig. 2 schematically illustrates a prior art Chain-Stitch
• Fig. 3 schematically illustrates a Chain-Stitch strengthened according to an embodiment of the invention
• Fig. 4 schematically illustrates the use of an upper thread bonded to the lower side of the fabric, according to another embodiment
• Figs. 5a an 5b schematically illustrates the bonding of fabrics by adhesives without the use of a thread
• Figs. 6 and 7 schematically illustrate the bonding without interlocking of a thread, passing through the fabric from one side thereof, to another thread located on the other side of the fabric;
• Fig. 8 schematically illustrates an embodiment of the injection and polymerization phases of the method of the invention.
• Fig. 1 schematically illustrates in cross-section a conventional Lock-Stitch.
• the fabric stock to be sewn is shown as consisting of a single layer and being interrupted to leave open spaces where the two threads interlock.
• a similar style of illustration will be used in most figures, but it will be understood that in practice two or more layers of fabric are superimposed and stitched together and that threads pass though them without creating open spaces.
• the fabric stock is indicated by numeral 10, the upper thread by numeral 11, and the lower thread by numeral 12. It will be seen that loops of the two threads interlock at the points 13.
• Fig. 1 is merely illustrative of the prior art and does not relate to an embodiment of the invention.
• Fig. 2 illustrates, similarly to Fig. 1, a conventional Chain-Stitch. Two juxtaposed fabrics are indicated at 50-51, the thread at 52, and it is seen that the various loops of the threads interlock at points 54-.
• Fig. 3 shows the same Chain-Stitch as Fig. 2, but with the interlocking points 54 strengthened by an adhesive bond 53.
• the bond being made of a sufficiently elastic material, does not detract significantly from the flexibility and the elasticity of the textile structure, but secures the Chain-Stitch against unraveling.
• Fig. 4 shows a (single or double) thread 26 that passes from the upper side of fabric 27 to the lower side thereof and is adhesively bonded thereto as indicated at 28.
• Fig. 5a shows two fabrics 50 and 51 connected by adhesive seals 49 at spaced points.
• Fig. 5b shows how the adhesive bond is obtained.
• the two fabrics are advanced in the direction of the arrow and are spread apart as shown at 58 to permit injection therebetween of adhesive drops 55 by means of an injector 56.
• the fabrics are advanced by increments equal to the distance between successive seals 52 and are juxtaposed.
• Sources of UV light such as optical bundles 57 connected to a UV light generator, not shown, are placed at a predetermined position on the two sides of the fabrics. When each adhesive drop 55 reaches a position between said sources, UV radiation, is applied for a time and with a fluence sufficient to effect polymerization of the adhesive and transform the drops 55 into the seals 52.
• the fabrics could be advanced continuously and the UV light sources could be moved synchronically with it, so as to remain in the same relative position with respect to the fabrics for the time required to produce polymerization. If the polymerization occurs rapidly enough, depending on the type of the adhesives and on the fluence of the irradiation, no motion of the UV light sources will be required. In the embodiment shown in Figs. 5b, the UV light passes through the fabrics. Most fabrics are sufficiently permeable to the light to permit a sufficiently strong irradiation to permeate therethrough and produce the polymerization. Otherwise, it would be possible to move the UV light sources alternatively towards and away from the fabrics, to cause them to penetrate into the fabrics better to irradiate the adhesive. Synchronizing -8-
• Fig. 6 shows the stitching of a fabric 30 by means of an upper thread 31 which is passed through the fabric as shown at 32, and a lower thread 33, which is not passed through the fabric.
• the lowermost points of thread 31, closest to thread 33, are bonded to said thread 33 by adhesive 34.
• said lowermost portions of thread 31 are broadened to form loops 35, which afford a better area for the bonding to the thread 33 through the adhesive 34.
• Fig. 7 shows a similar embodiment in which a fabric 40 is stitched by means of a lower thread 41, which passes through the fabric as shown at 42, and a thread 43 which does not pass through the fabric.
• the two threads are bonded to one another by adhesive 44, which bond is permitted by bending thread 41 in hook-like shape, as indicated at 45.
• Fig. 8 illustrates the injection and polymerization of the adhesive in one embodiment of the invention.
• two fabric layers 50 and 51 are shown as stitched together by means of a Chain-Stitch generally indicated at 53.
• the adhesive is applied to the interlocking portions 54 of the Chain-Stitch.
• an injector 55 is shown having a nozzle 56, and a single drop 57 of polymer precursor is schematically shown as directed towards one of the points of interlock 54 in direction indicated by broken line 60, which will be called "the injection axis".
• a source of UV light 58 generates UV light radiation, which is directed by means of a fiber optic channel 59 or other suitable means to the same point of interlock 54, in a direction schematically indicated by broken line 61, which will be called "the radiation axis".
• the injector 55 may be of any suitable type, e.g., a piston injector, but works in a pulsed manner, viz. produces a drop of polymer precursor at a time.
• the UV generator may work in a pulsed or CW mode, as preferred, but at any rate, the radiation does not impinge on the polymer precursor's drops 57 until they have reached a place 54 where thread loops interlock. In this manner, premature polymerization is avoided. It will be understood that the distance between the injector and the generator and the angle between the ejection and the radiation axes may depend on the type of UV generator and of injector used, and, particularly, on whether the UV generator works in pulsed or CW mode.
• the apparatus of the invention shifts the fabrics, with the thread, synchronically with the ejection of a drop 57, at such a rate that the fabrics and the thread advance by a distance equal to the distance between two successive points of thread loop interlock in a time equal to the interval between the ejection of successive drops, and remains standing in a position in which one of such points will receive a polymer precursor drop during a period of time sufficient for the drop to reach its destination point and for the -10-
• the embodiment of Fig. 8 can be modified, if desired,, by causing the injection axis and the radiation axis not to intersect one another, but to intersect the thread to be bonded at points having a distance from one another that is equal to or a multiple of the distance between two successive points of thread loop interlock, or, in general, the distance between two successive bonding points.
• a drop of adhesive precursor will the deposited at a bonding point, and then polymerized at a position successively assumed by said bonding point.
• Fig. 8 shows the adhesive injection and polymerization in the case of the strengthening of Chain-Stitch, it will be evident that the adhesive can be so injected and polymerized in any embodiment of the invention.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Sewing Machines And Sewing (AREA)
• Laminated Bodies (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=11071418

Family Applications (1)

Country Status (4)

Families Citing this family (5)

Family Cites Families (10)

• 1999
  • 1999-04-12 AU AU33429/99A patent/AU3342999A/en not_active Abandoned
  • 1999-04-12 WO PCT/IL1999/000198 patent/WO1999052710A1/en not_active Ceased
  • 1999-04-12 JP JP2000543299A patent/JP2002511326A/ja active Pending
  • 1999-04-12 EP EP99914734A patent/EP1117536A4/de not_active Withdrawn

Also Published As

Similar Documents

Legal Events