US3406647A

US3406647A - Single thread knotted lockstitch seam

Info

Publication number: US3406647A
Application number: US617312A
Authority: US
Inventors: Michael K Rohrlick; Clein Brian
Original assignee: Elwood Realties Ltd
Current assignee: Elwood Realties Ltd
Priority date: 1967-02-20
Filing date: 1967-02-20
Publication date: 1968-10-22
Anticipated expiration: 1985-10-22

Description

Oct. 22, 1968 M. K. ROHRLICK ETAL 3,406,547

SINGLE THREAD KNOTTED LOCKSTITCH SEAM Filed Feb. 20, 1967 W n ran: I Mic/me! If. ROI/ Brian United States Patent 3,406,647 SINGLE THREAD KNOTTED LOCKSTITCH SEAM Michael K. Rohrlick and Brian Clein, Montreal, Quebec, Canada, assignors to Elwood Realties Ltd., Lachrne, Quebec, Canada, a corporation of Canada Filed Feb. 20, 1967, Ser. No. 617,312 4 Claims. (Cl. 112-438) ABSTRACT OF THE DISCLOSURE A novel type of single thread sewing stitch characterized in that a loop of the thread is pushed through the material at each of a series of consecutive stitch points and the base portion of each loop is attached to the end portion of the adjacent previous loop by making one backwardly pitching turn therearound and forwardly around itself and hence through the said end portion.

The present invention relates to the art of forming seams by means of successive stitches or chain stitches and particularly to a novel ravel proof stitch.

The novel stitch of the present invention may be defined as a ravel proof, seam forming, single thread, knotted lockstitch.

Single thread lockstitches are known as such and belong to an art which may be examplified by US. Patent No. 3,224,399 of Dec. 21, 1965, for instance.

Lockstitched seams are seams which are not susceptible to unravelling from some skipped or ruptured stitch positions. Seams formed of stitches such as outlined in the US. Government publication entitled Federal Standard No. 751a, classes 300 and 700 therein, have for their general characteristic, the interlacing of the threads. Interlacing requires that a quantity of thread be wound onto a bobbin or reel in the lower mechanism of a sewing machine. Since it is necessary for this bobbin or reel to pass through the loop formed by the needle of the machine, it follows that there is a practical limit to the size which may be given to the bobbin and therefore, to the actual amount or length of thread which may be held in reverse therein. As a result, frequent replenishment of the thread supply of the bobbin occasions equally frequent sewing work stoppages; this is a disadvantage which the present invention seeks to eliminate.

It is an object of the present invention to produce a seam which consists of positively interlocked stitches whereby unravelling of the seam in the event of any skipped or ruptured stitch is rendered impossible.

It is a further object of the invention to present a seam the stitches of which are formed from a single thread, thereby eliminating the necessity for using bobbins or reels in the lower mechanism of the sewing machine and for attending to their frequent replenishment.

It is a further object of the invention that the seam shall consist of stitches formed by the interlooping of the thread with itself rather than by the interlacing of one thread with itself or with another thread.

A better understanding of the invention will be had hereinafter from the disclosure of an embodiment of the invention, reference being bad to the annexed drawing wherein:

FIG. 1 is a perspective view of a scam in accordance with the present invention, the material in which the seam is practiced not being shown for the sake of clarity;

FIG. 2 is a top plan view of a seam in accordance with the invention;

FIG. 3 is a vertical cross section of the same, taken along line 3-3 of FIG. 2;

FIG. 4 is a bottom plan view of the same and FIG. 5 is an enlarged perspective view of a stitch in accordance with the invention and wherein the thread is shown loosened for easier visualizing.

In FIGS. 2, 3 and 4 the stitched seam is observed to be applied to two superposed layers of fabric 11 and 12. A single thread 13 is used throughout to form the seam. Loops of the thread 13 are passed through the layers 11 and 12 of the fabric at evenly spaced intervals by means of appropriate pointed instruments such as by means of a conventional eye pointed needle. A series of successive points at which the loops of the thread are passed through the layers of fabric 11 and 12 are indicated at 14 through 18 inclusively. The illustrated seam is formed by successive stitches and progresses from left to right as indicated by arrow 6.

In the fomation of the stitches illustrated in FIGS. 2, 3 and 4, the first loop 30 is temporarily detained by proper retainer means, such as by means of a hook. The following loop 31 which projects through the fabric layers 11 and 12 at 15 is taken around the bight 20 of loop such as by means of a looper or similar device. The loop 31 is then passed over itself at point 21 and therefrom through the bight 20 of loop 30. The loop 31 thus formed is pulled tight such as by means of the aforementioned hook (not shown in the drawing) which had previously retained the bight'ZO of loop 30. The bight 23 of loop 31 is now positioned for the next stitch to be made by the loop 32 formed at point of penetration 16.

We claim:

1. A stitch for the production of seams in fabric and the like materials from a single thread and characterized in that, at spaced apart points along a seam line, loops of said thread project through the material, each loop presenting a bight which is located adjacent the point at which the next loop projects through the material, said next loop first encircling the bight portion of the previous loop, then passing around itself and finally projecting through the bight of the said previous loop.

2. A stitch in a seam comprising a series of consecut1ve stitches in a material and formed from a single thread, said stitches being characterized in that they each present a loop projecting through the material, each loop extending across and terminating at a position adjacent to the corresponding loop of the next stitch and presenting a bight, said loop of the next stitch encircling the adjacent portion of the first mentioned loop, extending around itself from behind and passing through the bight of said first mentioned loop.

3. A seam of stitches in a material, said stitches produced from a single thread generally extending longitudinally of said seam and characterized in that each stitch comprises a loop of the thread which is forced through said material, encircles the end portion of the corresponding loop of the previous stitch and then passes around itself and through the end of the said corresponding loop of the previous stitch.

4. A single thread knotted lockstitch seam presenting a series of consecutive stitches through a material, each stitch consisting of a loop of the single thread passing through the material from one side to the reverse side thereof, extending therefrom fully around the loop of the preceding stitch and thence around itself and through the said loop of the preceding stitch to terminate in the vicinity of the following stitch.

References Cited UNITED STATES PATENTS 23,984 5/1859 McCurdy 112438 1,657,989 1/1928 Baker 112-197 2,906,224 9/1959 Henry 112-262 3,224,399 12/ 1965 Lightner et al. 112-262 RICHARD J. SCANLAN, JR., Primary Examiner.