GB1577472A

GB1577472A - Method and apparatus for forming yarns

Info

Publication number: GB1577472A
Application number: GB3034677A
Authority: GB
Original assignee: Institute Po Obleklo I Textil
Current assignee: Institute Po Obleklo I Textil
Priority date: 1977-07-19
Filing date: 1977-07-19
Publication date: 1980-10-22

Description

(54) METHOD AND APPARATUS FOR FORMING YARNS (71) We, INSTITUTE PO OBLEKLO I TEXTIL, 48 Voyvodina Mogila Street, Sofia, BULGARIA, a Research Institute organized under the Laws of Bulgeria, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a method of, and an apparatus for, stopping a rotating hollow spindle twisting machine in response to breakage of at least one of the component threads of the fancy yarn being produced.

A method for stopping such a machine is known, according to which method each of the component threads is controlled individually. For this purpose, provided in the path of each thread is a protective device which reacts, for example, to a reduction in the tension of the thread, to a lack of supply of the thread, or to parting of the thread.

However, with this method it is difficult to follow directly the path of the tie thread which unwinds freely from the hollow spindle. This requires the use of complex equipment which, even so, does not guarantee good results.

The present invention therefore aims to provide a method of, and a apparatus for, stopping the machine in the event of the base thread or the tie thread parting.

According to one aspect of the present invention there is provided a method of stopping a rotating hollow spindle twisting machine in response to breakage of at least one of the component threads of the fancy yarn being produced, wherein the loops of the yarn are restrained by means of a hook in the case of parting of at least one of the component threads so as to reduce the tension in the yarn and to actuate a tensometer which senses the tension in the produced yarn, the tensometer, in turn, stopping the machine.

According to a second aspect of the present invention there is provided an apparatus for effecting the method of the present invention, which apparatus comprises a contact tensometer having a sensing arm which in use is in contact with the yarn in a region between a pair of pressing rollers and a yarn guide and a hook, for restraining the loops of the yarn when at least one of the component threads parts, located immediately upstream of the yarn guide.

The tensometer may be in the form of a strain gauge.

For a better understanding of the present invention and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawing which shows one embodiment of an apparatus for effecting the method of the present invention.

The apparatus comprises a thread guide 3 to which are supplied a base thread 2 and an effect thread 1. After passing through the thread guide 3, the two threads pass between a first pair of pressing rollers 4.

Located between the first pressing rollers 4 and a second pair of pressing rollers 7 is a hollow spindle 5 having wound thereon a tie thread 6. Between the two pairs of pressing rollers, the threads 1 and 2 are twisted together and, at the same time, the tie thread 6 is twisted into the threads 1 and 2 to form the desired fancy yarn. After passing between the second pressing rollers 7, the yarn passes through a yarn guide 10 to a roller 13.

Disposed about 0.5 mm upstream (with regard to the yarn) of the yarn guide 10 is a small hook 9 and disposed between the yarn guide 10 and the second pressing rollers is a contact tensometer 12 having a sensing arm 11. The contact tensometer may be, for example, in the form of a strain gauge.

In operation of the apparatus, should the tie thread 6 part, the loops formed around the base thread 2 by the effect thread 1 will - increase in size. Some of these loops will be caught by the small hook 9 and this will interrupt the winding of the finished yarn over the roller 13. However, the second pressing rollers 7 will continue to feed the base thread 2 and effect thread 1 and this will cause a reduction in the tension in the yarn between the yarn guide 10 and the second pressing rollers 7 and the sensing arm 11 will be deflected and will operate the tensometer 12 to stop one or more working positions of the machine of which the device forms a part.

If the base thread 2 should part, the tension of the yarn between the yarn guide 10 and the second pressing rollers 7 will again be reduced and the one or more working positions of the machine will again be stopped.

WHAT WE CLAIM IS: 1. A method of stopping a rotating hollow spindle twisting.machine in response to breakage of at least one of the component threads of the fancy yarn being produced, wherein the loops of the yarn are restrained by means of a hook in the case of parting of at least one of the component threads so as to reduce the tension in the yarn and to actuate a tensometer which senses the ten sion in the produced yarn, the tensometer, in turn, stopping the machine.

2. A method according to claim 1 and substantially as hereinbefore described with reference to the accompanying drawing.

3. An apparatus for effecting the method according to claim 1 or 2, which apparatus comprises a contact tensometer having a sensing arm which in use is in contact with the yarn in a region between a pair of pressing rollers and a yarn guide, and a hook, for restraining the loops of the yarn when at least one of the component threads parts, located immediately upstream of the yarn guide.

4. An apparatus as claimed in claim 3, wherein the tensometer comprises a strain gauge.

5. An apparatus for stopping a rotating hollow spindle twisting machine substantial ly as hereinbefore described with reference to, and as shown in, the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

the base thread 2 by the effect thread 1 will - increase in size. Some of these loops will be caught by the small hook 9 and this will interrupt the winding of the finished yarn over the roller 13. However, the second pressing rollers 7 will continue to feed the base thread 2 and effect thread 1 and this will cause a reduction in the tension in the yarn between the yarn guide 10 and the second pressing rollers 7 and the sensing arm 11 will be deflected and will operate the tensometer 12 to stop one or more working positions of the machine of which the device forms a part.

If the base thread 2 should part, the tension of the yarn between the yarn guide

10 and the second pressing rollers 7 will again be reduced and the one or more working positions of the machine will again be stopped.

WHAT WE CLAIM IS: 1. A method of stopping a rotating hollow spindle twisting.machine in response to breakage of at least one of the component threads of the fancy yarn being produced, wherein the loops of the yarn are restrained by means of a hook in the case of parting of at least one of the component threads so as to reduce the tension in the yarn and to actuate a tensometer which senses the ten sion in the produced yarn, the tensometer, in turn, stopping the machine.
2. A method according to claim 1 and substantially as hereinbefore described with reference to the accompanying drawing.
3. An apparatus for effecting the method according to claim 1 or 2, which apparatus comprises a contact tensometer having a sensing arm which in use is in contact with the yarn in a region between a pair of pressing rollers and a yarn guide, and a hook, for restraining the loops of the yarn when at least one of the component threads parts, located immediately upstream of the yarn guide.
4. An apparatus as claimed in claim 3, wherein the tensometer comprises a strain gauge.
5. An apparatus for stopping a rotating hollow spindle twisting machine substantial ly as hereinbefore described with reference to, and as shown in, the accompanying drawing.