FR2496454A1 - TRICOTE ELASTIC BANDAGE - Google Patents

Abstract

THIS LIGHTWEIGHT POROUS KNITTED ELASTIC BANDAGE INCLUDES A CHAIN CONSISTING OF A SET OF 12 KNITTED TEXTURED YARNS IN A CHAINETTE AND A SET OF FLOATING YARNS 14. THESE TWO SETS COMBINED BY TWO SETS OF NON-ELASTIC WEFT YARNS 16, 18. OF WEFT 16, 18 ARE DEPLOYED IN A REGULAR DESIGN AND REPEATED THROUGHOUT THE WIDTH OF THE BANDAGE AND ARE INTERLACED IN 20 WITH THE MESH OF THE YARNS 12 KNITTED CHAINS, ONE OF THE SETS OF WEFT THREADING OVER AND OTHER BELOW FLOATING WIRES WITHOUT BEING INTERLACED WITH THEM.

Description

The present invention relates to an elastic bandage

than knitted.

  Elastic bandages have been manufactured in the past by weaving on narrow looms or looms, the contraction and support capacity being given by special catwire threads. The old bandages used overstretched cotton warp yarns, but the use of cotton warp was largely supplanted by the use of elastomeric warp yarns originally made of extruded or cut rubber but more recently synthetic elastomeric polymers. Such warp yarns

  elastomer material are usually wrapped in a

of non-elastomeric filaments.

  Such bandages, although they are effective in

  vice, have the disadvantage of being relatively expensive.

  They are produced one by one on a narrow craft using

  expensive wrapped elastomeric material yarns at

  these relatively slow production, inherent in the process

weaving.

  In order to try to avoid the limitations of

  weaving, it has already been proposed to produce bandages

knit elastics.

  Most of the knitted bandages that have been proposed use elastomeric threads as part of the chain structure and usually use very heavy weft threads to prevent lateral shrinkage of the bandage when stretched. These bandages are relatively heavy, weighing on average between 204 and 408 g per square meter, and, because of their compact structure, they quickly become

hot and uncomfortable to wear.

  In US Pat. No. 4,173,131 of the Applicant, the manufacture of a lightweight elastic bandage has been described in which the catenary yarns consist of a set of false twist yarns formed into chain stitches, a second yarn false twist whose direction of torsion is opposite being

  passed in each of said wires. The weft threads are depleted

  yés across catnip threads in various designs and

  cursive, so that the layers of the bandage

  crocheted to each other in a relative non-movable relative disposition. Bandages of this nature, although they are very satisfactory to use, are of a relatively complex manufacture due to the need to form each chain son chafnette with a second warp passed in each catnette and because of the complicated drawing of

weft threads.

  The present invention relates to an elastic bandage

  knitted scarf which includes a set of catnip threads

  Textured floats formed of net stitches, a set of textured floats that extend parallel to but not bound to said set of cat threads, and two sets of nonelastic weft yarns that are deployed

  following a regular and repetitive pattern across the

  bandage, the weft threads being intertwined with the

  of at least some of the warp knitted warp yarns

  net and a set of weft son passing above and one other set of weft son passing under the son

  floating without being intertwined with them.

  The elasticity of the bandage according to the invention is provided by the elongation and the inherent recovery of the textured warp yarns. Such yarns are continuous filament yarns to

  increased swelling and volume as well as an ex-

  elastic tensile for introduction into the crimson wire,

  loops, tendrils and undulations, by means of a false method

  twisting. Such yarns are produced industrially by well-known methods, and when the filamentary material is thermoplastic, as is the case when using nylon or polyester, a heat-setting step carried out at

  during the process of false torsion makes the configuration ex-

  Tensile and curly thread relatively permanent.

  The thread can be twisted in the direction of the needle

  does not show or in the opposite direction during the process of false twist to produce so-called S twist or torsion wires

  Z. In most light bandages, it is desirable to

  use an approximately balanced number of S-twisted yarns and Z-twisted yarns in the

  the tendency of the bandage to bend when

  the. To reduce the tendency of the bandage according to the invention to bend or twist, it is preferable that there be a contribution approximately equal to the torque of the twist wires S and the torsion wires Z which form the whole of the cha bandage. This can be achieved in various ways,

  as described in more detail below.

  Other features and advantages of the invention

  will be apparent from the following description, given as

  of non-limiting example and with reference to the attached drawing, on the-

what:

  FIG. 1 is an enlarged isometric view

  both a pattern of the basic structure of a knitted elastic bandage according to the invention; FIG. 2 is a sectional view on a large scale of a false twisted string wire; FIG. 3 schematically represents the paths of

  catenary son and a set of weft threads in the seg-

  bandage shown in FIG. 1; FIG. 4 shows the paths of the two sets of weft yarns interlaced with a warp yarn; and

  FIG. 5 represents, on a large scale, a detailed

  the interlacing of the two sets of weft yarns with

  a warp thread formed into net knits.

  Fig. 1 shows a drawing pattern of a bandage 10 which comprises two sets of catenary wires 12 and 14 which have

  both textured nature and are likely to

  ger. Each yarn 12 is formed into a series of cat stitches.

  net, as shown in Fig.5, and two weft son

  inelastic 16 and 18 are passed in each of his mail-

  the, as indicated by reference 20. Each wire 14 is a floating wire which simply passes between the weft son 16

  and 18 and is not knitted with the other threads of the bandage.

  Floating yarns increase the stability of the bandage and

  increase the hedge index (ie, next

  American standard, the number of threads per inch (2.54 cm)

  covered by the square root of the title of the thread). The preferred range of combination warp yarns and yarns is 20 to 40 threads (2.54 cm) (about 8 to about 16 threads per centimeter), and these threads are preferably between 70 and

230 deniers.

  The warp knitted yarns 12 as well as the floating yarns 14 may be constituted by a mixture of

  son & torsion S and Z twist wires. They are not born

  ceased to come back in a strictly al-

  tary, since a beam of twisted wires S and

  a beam of Z-twist wires can be mixed

  random pattern to form a stable bandage without torpor

  provided that the number of wires of each type of tor-

  is approximately the same. In addition, it is not essential that there be the same number of floating wires and

  warp threads alternating across the width of the bandage.

  Since the main function of the floating yarns is to give weight and stability to the bandage, the ratio of the chain-knit yarns to the floating yarns can range from two or more to one and one to two or more, depending on the

title of the threads.

  As a variant, a more convenient method that can be used for

  balance torsion wires S and torsion wires Z con-

  It is possible to use warp yarns all having the same type of twist and floating yarns all having the opposite type of twist. This is the preferred method when there are approximately equal numbers of knitted warp yarns and

  floating yarns having a similar degree of torsion.

  Although in FIG. 1 the weft yarns 16 and 18 have been shown as passed through 20 in the stitches of all knitted yarns 12 chained, this feature is not essential. The main function of the weft threads, apart from keeping the assembled chalk threads in a unitary structure, is to give

  bandage transverse stability and resistance to

  required, when lying down. This varies depending on the number and the number of weft threads, which are preferably cotton threads with a title ranging from 1: 1 to 30: 1, with 10 to 20 weft threads per inch (2.54 cm). )

  (from about 4 to about 8 threads per centimeter).

  The weft threads are deployed in a regular pattern.

  tie and repeat across the width of the bandage, each thread

  weft extending above 5 to 9 catenary threads.

  As shown in FIG. 2, each chalk yarn is a false twist yarn 22 formed of textured filaments 24. FIG. 3 schematically shows how the weft yarns 16 are passed, at 20, into the stitches of the yarns 12 of FIG. chalne. Fig. 4 shows the interlacing of the two weft threads 16 and 18 with

the wires 12 of chalne in 26.

  The bandage may be made on a crochet machine using three thread guide bars per pattern which

  operate in a vertical plane perpendicular to the

  the horizontal of the machine. Two of the bars are moved across the width of the bandage to introduce the wires

  weft 16 and 18 in 20/1 cotton, and the third bar is used

  to introduce the textured floating yarns 14, which are

  Z-twist textured and heat-set nylon yarns of approx.

  about 140deniers. Yarns 12 knitted in a chain have the same title, but they have a twist S. As shown in FIG. 1, there are five knitted yarns in chain and four floating yarns per complete pattern of the drawing. The design of the weft threads is that shown in FIGS. 1 and 3, in which all the weft threads 16 and 18 in cotton are interlaced with

  each of the warp yarns 12 knitted in a chain but not

  simply feel above and below the floating wires 14 without being intertwined with them. There are 18 picks per inch

  (2.54 cm) (about 7 centimeters per centimeter of

dage>

  Since the bandage, as formed on the machine,

  has a certain degree of internal stress due to the tensions applied to the various wires during the treatment, it has been conditioned by exposing it to wet steam at 80 ° C.

  for about two minutes, after which it was dried.

  The weight of the dried and relaxed bandage was 140 g / m The finished bandage had an air porosity of more than 3 2

  220 m / m per minute at a pressure of 1.27 cm, during

  using the Frazier air permeability meter. At 100% elongation, the bandage had 9 picks

  or weft threads (2.54 cm) (about 3.5

  timètre). The hedging index was therefore 2 according to American standards (9 / VaTO, the title of the wire being 20). This is a very low hiding index, characteristic of an open mesh net. Combined with the scattered, fluffy pattern of textured warp yarns, this ensures breathability and comfort to the use that one

  does not get with conventional elastic bandages.

  Apart from being light and comfortable to wear

  ter, the bandage according to the invention is absorbent and can be

  washed and sterilized without degradation. Since it does not

  holds neither rubber nor synthetic elastomeric material, it can be used in cases where elastomeric threads

  in contact with the skin produce an allergic reaction.

  It will be understood by those skilled in the art that, unlike the manufacture of bandages woven on a narrow loom, the knit bandages according to the invention can be produced on a wide flat needle machine, and a series of bandages can be produced if desired. of various widths, in one

  unique operation of the machine using a wire assembly

  between individual bandages, if necessary. The sons of

  can be produced by needles that move

  back and forth between adjacent bandages and can

  be easily removed afterwards by a fray operation

ge.

Claims (7)

  1 - Knitted elastic bandage warp, characterized in   it comprises a set of parallel threads tex-   (12) formed of chain stitches, a set of textured floats (14) extending parallel to but not bound to said set of warp threads, and two sets of non-elastic weft threads (16, 18) which are deployed in a regular and repetitive pattern across   the width of the bandage (10), the weft threads being   laced with the stitches of at least some of the warp knitted warp yarns and a set of weft threads   above and the other set of weft wires passing over   under floating wires without being intertwined with them.   2 - Bandage according to claim 1, characterized in that the number of chain son (12) knitted in chain   is approximately equal to the number of floating wires (14).   3 - Bandage according to claim 2, characterized in   what the yarns (12) are knitted in chains and the yarns are   tants (14) alternate over the width of the bandage.   4 - Bandage according to claim 1, characterized in that   that the total number of warp yarns (12) knitted   net and floating wires (14) contains an approximate   correspondingly equal to S twist wires and Z twist wires. - A tire according to Claim 2, characterized in that   that the floating yarns (14) and the yarns (12) knitted in cat- net have opposite twists.   6 - Bandage according to claim 1, characterized in that   that the weft threads (16, 18) are interlaced with the mail-   of all the yarns (12) knitted in a chain.   7 - Bandage according to claim 1, characterized in   textured warp threads are made of a thermo material heat-set plastic.   8 - Bandage according to claim 1 characterized in that   that the sets of weft threads (16, 18) are deployed   above five to nine warp threads.