US3733859A

US3733859A - Warp knit elastic fabric

Info

Publication number: US3733859A
Application number: US00069761A
Authority: US
Inventors: C Wittmann
Original assignee: Darlington Fabrics Corp
Current assignee: Darlington Fabrics Corp
Priority date: 1970-09-04
Filing date: 1970-09-04
Publication date: 1973-05-22
Anticipated expiration: 1990-05-22

Abstract

An elastic warp knit fabric having two base non-elastic yarns interlooped to form a net with one of the base yarns being knitted for a plurality of successive causes in a single wale and having in addition an elastic yarn laid in the successive courses of the base yarn and crossing over adjacent wales where it is laid in further successive courses whereby the elastic yarn may allow the fabric to stretch and contract in a plurality of directions. Method for making an elastic warp knit fabric which may stretch and contract in a plurality of directions comprising the steps of knitting two base non-elastic yarns to form a net where one of the base yarns is knitted into a plurality of successive courses in a single wale and laying in an elastic yarn in the successive courses and crossing the elastic yarn over adjacent wales and laying it into other successive courses.

Description

United States P316? 1 Wittmann [54] WARP KNIT ELASTIC FABRIC [75] Inventor: Christoph J. Wittmann, Newton,

[73] Assignee: Darlington Fabrics Corporation,

New York, N.Y. [22] Filed: Sept. 4, 1970 [21] Appl. No.: 69,761

[52] U.S. Cl ..66/193 [51] Int. Cl. ..D04b 23/06 [58] Field of Search ..66/192, 191, 195, 66/193 [56] References Cited UNITED STATES PATENTS 3,389,582 6/1968 Alexander ..66/l92 3,552,155 1/1971 Hartung 66/192 2,153,645 4/1939 Schonfeld 66/192 3,084,529 4/1963 Scheibe t .66/193 3,011,325 12/1961 Elsas et a1 ....66/192 X 3,241,341 3/1966 Winter ..66/193 FOREIGN PATENTS 0R APPLICATIONS 237,490 2/1962 Australia ..66/l92 1 3,733,859 1 May 22,1973

1,585,445 9/1969 Germany ..66/l92 Primary Examiner-James Kee Chi Att0rneyPennie, Edmonds, Morton, Taylor and Adams 57] ABSTRACT Method for making an elastic warp knit fabric which may stretch and contract in a plurality of directions comprising the steps of knitting two base non-elastic yarns to form a net where one of the base yarns is knitted into a plurality of successive courses in a single wale and laying in an elastic yarn in the successive courses and crossing the elastic yarn over adjacent wales and laying it into other successive courses.

5 Claims, 2 Drawing Figures Patented May 22, 1973 2 Sheets-Sheet 1 Patented May 2-2," 1973 2 Shootl-Shoet 9 1 WARP KNIT ELASTIC FABRIC FIELD OF THE INVENTION DESCRIPTION OF THE PRIOR ART Conventional types of elastic fabrics using bare or covered spandex yarns or bare or covered rubber yarns usually have the elastic yarns follow in the direction of the wales of the fabric when the fabric is relaxed. While such fabrics may stretch in both directions, they contract positively only in the direction of the wales and as such have higher power characteristics in the warp direction than in the side or weft direction. Such fabrics are for the most part used in foundation garments and since they effectively only contract in one direction, can result in discomfort to the wearer.

SUMMARY OF THE INVENTION Broadly described, a warp knit elastic fabric according to the invention is made up of at least two nonelastic base yarns and an elastic yarn. One of the base yarns is knitted for one loop or course in a first wale and then crosses over to an adjacent wale where it is knitted for one loop or course and then returned to the first wale where the pattern is repeated. The other base yarn is knitted for a plurality of successive loops or courses in the first wale and then crosses over to the adjacent wale where it is knitted for a plurality of successive loops or courses and then returned to the first wale where the pattern is repeated. The two base yarns are interlooped to form a net construction. An elastic yarn is laid into the successive loops or courses of the first wale and crosses in the weft direction over at least one wale where it is then laid into the successive loops or courses of a third wale formed by a thread ofa yarn not included in the first wale and then is returned to the first wale where the pattern is repeated. The elastic yarn will appear to have a zigzag appearance on the fabric and will be available to stretch and contract in the warp direction where it is laid into successive loops or courses and stretch and contract in the weft direction where it crosses over adjacent wales.

The fabric may be made on conventional Raschel machines or other warp knitting machines, i.e., tricot machines. The method used for making the fabric involves knitting a first base yarn for a plurality of successive loops or courses in a first wale, then crossing the yarn over to an adjacent wale where it is knitted a plurality of successive loops or courses and then returning it to the first wale. The second base yarn is knitted for one loop or course in the first wale, then crossed over to an adjacent wale where it is knitted once and then returned back to the first wale. The elastic yarn is laid into the successive loops or courses of the first base yarn and then moved side-ways over an adjacent wale and laid into the successive loops or courses of a further first base yarn and then returned back to the first wale.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic sketch illustrating the preferred stitch configuration of a warp knit elastic fabric made according to the invention; and

FIG. 2 is a stitch construction diagram of the fabric of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 which illustrates a proposed embodiment of my invention, there is shown a warp knit elastic fabric having two

base yarns

2 and 3. The yarns are non-elastic and may comprise any natural or synthetic material. As shown, a guide bar 1 of a three bar Raschel knitting machine is threaded with the base yarn 2. Three chain or pillar stitches are knitted in succession to form three successive loops or

courses

4, 5 and 6, after which the guide bar shogs one needle width to the left where the additional successive loops or

courses

7, 8 and 9 are knitted. The guide bar 1 then moves back to its starting position where additional loops or courses similar to loops or

courses

4, 5 and 6 may be knitted to form a repeat pattern.

Guide bar 2 is threaded with a further non-elastic base yarn 3 and moves alternately from right to left forming a single loop or course at the end of each swing of the guide bar to form with the base yarn 2 an interknitted fabric net.

For ease in illustrating the fabric construction, only three of the base 2 yarns have been illustrated, namely 2, 2 and 2", and only two of the base 3 yarns are illustrated, namely 3 and 3'. It will be understood that when the base yarns are inter-knitted, that they will form wales 10 through 15. For further ease in understanding the drawings, only some of the guide bars have been illustrated, it being understood that each yarn will have an associated guide bar.

A guide bar 3 is threaded with an elastic yarn 16 which forms part of the body of the fabric. As shown, the elastic fabric is laid into the loops or courses 4', 5 and 6 of the 2' base yarn of wale 11 as well as the single loops or courses formed by the yarn controlled by the bars 2 of the machine. Bar 3 is then shogged to the left so that it passes under three needles as a short weft insertion and so that the elastic yarn crosses over at least one adjacent Wale 12 after which the elastic yarn is laid into the loops or courses 7", 8" and 9" of the base yarn 2" comprising wale 13. Bar 3 is then moved back to the right so that it passes under three needles and is returned to wale 11 where it is again in position to be laid into further loops or courses of yarn 2' to form a repeat pattern.

FIG. 2 is a stitch construction diagram of the fabric of FIG. 1 and illustrates diagrammatically the combined movement of the guide bars.

The elastic yarn may be a spandex yarn, a covered rubber yarn or a bare rubber yarn, the only requirement being that it stretch and contract positively. By following the pattern shown in the drawings, it is seen that the elastic fabric may stretch in the warp direction along the wales or in the weft direction across the wales and since the yarn also has contraction properties, it is seen that there will be positive contraction to the fabric when it is stretched in the warp, weft or in any intermediate direction.

It is seen by reference to the stitch diagram of FIG. 2, that the pattern of repeat occurs every six courses. The pattern of repeat, however, could be less, for example four courses, or more, for example eight courses. In such event, the number of successive loops or courses 4, S and 6 would be varied so that in the event a four course repeat pattern were used, the successive loops or courses would number preferably two, and in the event an eight course repeat pattern were used, the successive loops or courses would number four.

Further, the portion of the elastic fabric extending over the wales could be varied so that the yarn could extend over more than one adjacent wale. The general requirement in order to provide fabric having the same general degree of stretchability and contractability in all directions would be that the elastic yarn would extend over more wales when the greater number of successive loops or courses of the basic yarn are formed and over less wales when a minimum number of successive loops or courses of the base yarn are used. Also, the laps formed by the base yarns over the needles of the machine may be open or closed laps or a combination of the same.

The fabric as constructed according to the invention is applicable for use in situations requiring positive twoway stretch and recovery such as foundation garments, swimming suits, athletic wear, footwear, upholstery fabric or in industrial applications where uniform highdirectional stretch and stress becomes a factor such as use with inflatable domes.

I claim:

1. An elastic warp knit fabric having a base net configuration comprising a plurality of first and second base yarns knitted in side-by-side relation in parallel wales with one of said base yarns being knitted for a plurality of successive courses in a first wale and then having a first cross-over portion extending into a second wale where it is knitted for a plurality of successive courses and then having a second cross-over portion extending back into said first wale, one of said second base yarns being knitted into said first wale for one course and then having a first cross-over portion extending over into said second wale where it is knitted into said second wale for one course and then having a second cross-over portion extending back to said first wale such that said first and second base yarns are interlooped, and an elastic yarn inlaid into the plurality of successive courses in said first wale and then having a first cross-over portion extending over at least said second wale and then being inlaid in a third wale into a plurality of successive courses formed by another first base yarn and then having a second cross-over portion extending back over said second wale to said first wale.

2. An elastic warp knit fabric according to claim 1 wherein the first base yarn is knitted upon itself for at least three successive courses in a single wale.

3. An elastic warp knit fabric comprising two sets of base yarns with each base yarn of one set knitted for a single course in a first wale and then for a single course in a second wale and having cross-over portions zigzagging between said first and second wales, each base yarn of the other set knitted for a plurality of successive courses in said first wale and then for a plurality of successive courses in said second wale and having crossover portions connecting said first and second wales, said two sets of base yarns being in interlooped relation; and an elastic yarn laid into the plurality of successive courses in said first wale and into a plurality of successive courses in a third wale formed from a base yarn separated from said first wale and where said elastic yarn has cross-over portions connecting said first and third wales.

4. A method of making an elastic warp knit fabric comprising the steps of knitting each of a first set of base yarns to form a plurality of successive courses in a first wale, shifting each of said first set of yarns laterally and forming a plurality of successive courses in a second wale adjacent to said first wale, shifting each of said first set of base yarns laterally back to said first wale to repeat the pattern; knitting each of a second set of base yarns to form an individual course in one wale, shifting each said second set of base yarns laterally to form an individual course in a second wale, and then shifting each said second set of base yarns to said first wale to repeat the pattern; and laying an elastic yarn in the plurality of successive courses in said one wale, shifting said elastic yarn laterally at least one wale, laying said elastic yarn in a plurality of successive courses of a yarn of the first set of base yarns different from that in said first wale, and returning said elastic yarn to said first wale to repeat the pattern.

5. A method of making an elastic knit fabric according to claim 4 wherein each of said first set of base yarns is knitted to form three consecutive loops.

Claims

3. An elastic warp knit fabric comprising two sets of base yarns with each base yarn of one set knitted for a single course in a first wale and then for a single course in a second wale and having cross-over portions zigzagging between said first and second wales, each base yarn of the other set knitted for a plurality of successive courses in said first wale and then for a plurality of successive courses in said second wale and having cross-over portions connecting said first and second wales, said two sets of base yarns being in interlooped relation; and an elastic yarn laid into the plurality of successive courses in said first wale and into a plurality of successive courses in a third wale formed from a base yarn separated from said first wale and where said elastic yarn has cross-over portions connecting said first and third wales.