November 09, 2009.
To: Suzhou Wanping Sewing Equipment Co. Ltd.
Add.: 1 Wanping Road, Wanping Town, Wujiang County, Suzhou City, Jiangsu Province, CHINA.
P.C.: 215223
TEL.: ***8
From: Mr. Zarif Sh. Tadjibaev,
Inventor-Applicant of U.S. Patent No. 6095069,
Doctor of philosophy in tecnics.
E-mail: ***mail.ru , ***
Website: ***
RE: New technology of obtaining of double thread chain stitch «ZARIF» with use of rotating looper.
The historical information:
1. In 1858 the American inventor James Gibbs has invented rotating looper for obtaining of one thread chain stitch.
2. In 1994 the Uzbek inventor Tadjibaev Zarif used rotating looper for obtaining of double thread chain stitch.
Dear Sirs,
We in 29 of August of this year on your post address sent the letter with a DVD disk where our film No.1 has been written down.
We ask you inform us, you have received this our letter with a DVD disk or have not received.
If you have not received our a DVD disk, we are ready to send to you new our a DVD disk where our films No.1 and No.2 are written down and also our patent of the USA No. 6095069.
We in 1994 have invented new technology of obtaining of a stitch and on the basis of our technology in the future can be made the various industrial sewing-machines, special sewing-machines, sewing semiautomatic devices and automatic machines etc.
Thereupon, we would like to learn your interest in application of our new technology of obtaining of a stitch in your Products or to make new Products on the basis of our invention.
We are always ready to co-operate with your company in use of our new technology of obtaining of a stitch in various sewing technicians if your company has an interest in our invention.
Now we used our new technology of obtaining of a stitch in the sewing-machine with a flat platform and the bottom feed, for sewing by a one-linear line double thread chain stitch, both in a direct moving, and in reverse moving of a material.
Our pre-production model of the sewing-machine is made of the lockstitch sewing-machine 1022 classes of Belarus Company «Orsha».
The design of the lockstitch sewing-machine 1022 classes has two conic gear drives. We to place our new technology of obtaining of a stitch in a design of the lockstitch sewing-machine 1022 classes used two more cylindrical gear drives and one conic gear drive.
Because of a considerable quantity of gear drives our pre-production model of the new sewing-machine at sewing publishes high noise.
At manufacturing of a production version of our sewing-machine with a flat platform it is possible to use only one cylindrical gear drive (look our Website: *** section «Documents», Pages No.3). A shaft of looper very short, weight of looper small and at sewing-machine work on looper the big loadings from threads do not operate. All these circumstances allow us to make a cylindrical gear drive of special plastic or from textolite. The quantity of consumed oil and noise as a result less at sewing-machine work.
Our new sewing-machine surpasses in technical and technological indicators of existing sewing-machines lockstitch and double chain stitches.
The most basic problem of lockstitch sewing-machines it, frequent refuelling of a spool of a hook with the bottom thread. Unfortunately, this problem to be among not solved problems.
And the most basic problem of existing sewing-machines double chain stitch it, participations of a needle in preliminary tensioning of a loop of the top thread being on the previous stitch.
Because of this problem in the sewing-machine the needle with two long groove is applied, impossibly densely to connect medium, heavy and leather materials.
Our new sewing-machine is the most perfect for sewing of various materials by an one-linear stitch line.
You can be convinced of it having looked our films No.1 and No.2.
In our films No.1 and No.2 we did not regulate working units of the sewing-machine, at change of a thickness and rigidity of a sewed material, and also at change of number of a needle.
Therefore our new sewing-machine is very simple in maintenance service.
For the first time our new sewing-machine could connect densely sewed materials a line of double thread chain stitch, at the expense of application in it new technology of obtaining of a stitch.
As is known, that with the help of double thread chain stitch to obtaining dense connection of materials it is necessary as it is possible to tighten more strongly a loop of the top thread in a stitch.
In a film No.1 it is reached at a normal tension of the top thread, at the expense of know-how application. In a film No.2 it is reached by increase in a tension of the top thread.
Very interestingly that in both films the bottom thread has a normal tension and remains to constants. All it is reached at the expense of application of other know-how.
Our films show technical and technological possibilities of our new sewing-machine. During demonstration we have not opened know-how of new technology of obtaining of a stitch.
We are ready, to open to you all a know-how of new technology of obtaining of a stitch if your company is interested in our invention and is ready to co-operate with us on use of our invention in the sewing technics.
We think, that the following technical and technology characteristics on our new sewing-machine, can interest buyers of industrial sewing-machines very much:
1. One sewing-machine for all materials (light, medium, heavy, elastic and leather). Thus the thickness of a sewed material can be to 7 mm at a needle bar stroke of 32 mm (films No.1 and No.2);
2. The mechanical design of the sewing-machine and a design of working units are very simple;
3. Working units of the sewing-machine have high service life as they in the course of work do not collide among themselves and other details of the sewing-machine;
4. All working units of the sewing-machine are located on the ends of shaft because of what they are easy for removing and can be replaced on new if necessary. Thus, all working units of the sewing-machine have low cost, as they very simple on a design;
5. In the sewing-machine for reception of qualitative connection of materials, depending on type of materials it is possible to regulate only pressure of a pressing leg upon a material and height of lifting toothed rack from a surface of needle plates. However we in our films No.1 and No.2 did not regulate these parameters;
6. In the sewing-machine for obtaining of double thread chain stitch is used the needle with one long groove as in our new technology the needle does not accept participation in an tension of a loop of the top thread which is on the previous stitch. It is known, that a needle with one long groove more a rack on a bend, than a needle with two long groove;
7. The sewing-machine at sewing does not skip any stitch, it is very important, as double thread chain stitch lines are very easily dismissed from a place of the skip of a stitch (films No.1 and No.2);
8. The sewing-machine works without breakages of threads, under a condition if on threads there will be no small knots. Our experiments have shown, what even at increase in a tension of threads there are no breakages of threads. It is possible to explain it to that reductions and tension of threads occur smoothly without blows on threads, by means of two rotating two dick-shaped cam thread tensioner for the top and bottom threads (films No.1 and No.2);
9. Top rotating two dick-shaped cam thread tensioner supply the top thread to a needle at turn of the main shaft for 50 therefore, the sewing-machine at needle bar stroke of 32 mm can sew materials with a thickness of 7 mm (films No.1 and No.2);
10. The sewing-machine densely connects textile and leather materials a line of double thread chain stitch. Thus, dense connection of materials can be received in two ways. In the first way, not changing a normal tension of the top thread, by know-how application (film No.1). In the second way, increasing a tension of the top thread (film No.2);
11. The sewing-machine allows receiving a smooth line on light materials and an elastic stitch line on elastic materials. Thus, the smooth and elastic stitch line can be received in two ways. In the first way, not changing a normal tension of the top thread, by know-how application (film No.1). In the second way, reducing a tension of the top thread (film No.2);
12. The sewing-machine can carry out all three ways the fixations the stitch line end: reducing length of a stitch to 0,5 mm; reverse seam; forming threads a chain on the brink of a material, by sewing without a material (films No.1 and No.2);
13. In the sewing-machine at transition to other type of a material or at change of a thickness and rigidity of materials, height of lifting of a needle from extreme bottom position, adjustments are not made for formation of a loop-overlap from the top thread as this height is constant. Also, at transition to other number of a needle it is not regulated looper concerning a needle as the maximum gap between a needle and a nose of looper is equal 0,5 mm (films No.1 and No.2);
14. The sewing-machine at sewing through thick places of a material standard needle DPx5 does not skip a stitch, therefore there is no necessity for application of special needles for prevention of the skip of a stitch (film No.1).
Except sewing-machines, our new technology of obtaining of a stitch can be used on various sewing semiautomatic devices and automatic machines.
Now in the majority sewing automatic machines the lockstitch is used. The most basic lack of these sewing automatic machines it, frequent refuelling of the bottom thread of a spool of a hook.
On the basis of our new method of obtaining double thread chain stitch, it is possible to create many the sewing automatic machines sewing in direct and in the reverse movement of a material.
For us are available ideas, on obtaining of double thread chain stitch at material moving to a range 3600. If it is possible to us on the basis of our new method of obtaining of double thread chain stitch, it will be possible to create sewing automatic machines where moving of materials occurs on a difficult trajectory.
As is known, in all automated sewing-machines and sewing semiautomatic devices, automatic machines, automatic thread trimmer are used.
We have developed recently very simple method of cutting of threads under needle a plate, with the subsequent clip of the end of the bottom thread, that the bottom thread not to fill anew.
After of cutting of threads, the end of the bottom thread it will appear passed through last loop of the top thread that allows receiving not dismissed stitch line from the end.
We in the future plan to patent this method of cutting of threads.
Replacement of a lockstitch on double thread chain stitch will lead to service life increase of thread connections.
It is known that, double thread chain stitch stronger in a cross-section direction, than a lockstitch. It was confirmed also with our experiments (look our Website: www.zarif.pisem, net section «Experiments»).
This results from the fact that in a lockstitch through a loop of the top thread there passes one branch of the bottom thread, and on double thread chain stitch through a loop of the top thread passes two branches of the bottom thread.
Besides, double thread chain stitch line is more elastic, than a lockstitch line.
Our new technology of obtaining of a stitch allows receiving very easily highly elastic double thread chain stitch line, by a tension of a loop of the top thread not to the end (films No.1 and No.2).
We are ready to co-operate with your company in application of our new method of obtaining double thread chain stitch in the industrial sewing-machines, special industrial sewing-machines (needle feed, differential feed, top and bottom feed, cylindrical platform, columnar platform etc.), sewing semiautomatic devices and automatic machines.
We ask you after reception of our letter and detailed studying of materials of the letter to direct us your decision concerning our invention, i.e. your company is interested or not interested in use of our invention in your Products or to make new Products on the basis of our invention.
If for decision-making it is necessary for you to look our films No.1 and No.2 we are ready to send them to you.
We ask you to direct your answer to ours e-mail: ***mail.ru
With impatience we wait for your e-mail.
Very truly yours,
Zarif Sh. Tadjibaev,
Contact Add: TS-13, d. 14, kv. 1, 100128 Tashkent, Uzbekistan.