Weaving installation allowing the number of filaments in a strand to be determined

1. A weaving installation comprising:

a loom configured to receive a series of strands, and

at least one device adapted to measure a diameter of a strand comprising a defined number of filaments, the device comprising a diaphragm comprising an external ring forming a support on which are attached a series of strips forming an iris, the strips being movable and allowing defining, at the centre of the iris, a circular space with variable dimensions,

wherein the diaphragm is configured to adjust the dimensions of the space so as to:

allow a strand of the loom to pass through it, and

encircle the profile of the strand, so as to allow the number of filaments of said strand to be determined.

2. The installation according to claim 1 , wherein the strips of the iris of the diaphragm occupy a first position in which the strips encircle the strand so as to compress the filaments between them in the space in a center of the iris.

3. The installation according to claim 1 , wherein the device is attached to the loom.

4. The installation according to claim 1 , wherein the device comprises a control element.

5. The installation according to claim 4 , wherein the control element is a scale allowing a measurement of a dimension to be taken.

6. The installation according to claim 5 , wherein the control element is a microprocessor and the diaphragm comprises a motor (M) connected to the microprocessor.

7. The installation according to claim 6 , wherein the microprocessor is configured to determine dimension corresponding to dimensions of the space and to keep them in memory.

8. A method for determining a number of filaments in a strand by means of an installation according claim 1 , the method comprising the steps of:

positioning the strand in the measuring device,

activating the device, and

determining the number of threads constituting said strand.

9. The method according to claim 8 , further comprising the steps of:

opening the measuring device so that the space has a larger diameter than that of the strand, after laying said strand on the loom,

passing the strand through the space of the device,

actuating the strips of the device to close the iris around the strand so as to clamp it between the strips and to adjust the dimensions of the space to the diameter of the strand,

reading the dimension corresponding to the diameter of the measured strand, and

determining the number of filaments forming said strand.

10. The method according to claim 9 , wherein the measuring device is a diaphragm and the last three steps are performed automatically.