Abstract: A plurality of unidirectional sheets (30a, 30b, 30c) are superposed in different directions and they are bonded together. At least one of the unidirectional sheets is made by spreading a tow so as to obtain uniform thickness, width not less than 5 cm, and a weight of no more than 300 g/m2, cohesion being imparted to the sheet so as to enable it to be handled prior to being superposed with other sheets. Advantageously, the unidirectional sheets are made of carbon fibers and are obtained by spreading out large tows.

Abstract: Process and system for fabricating a multidirectional fibrous reinforcement designed to be a porous preform for producing a part made of a composite material. Reinforcing thread is deposited in successive layers on a support surface. A binder is provided in association with the reinforcing thread so as to adhere the reinforcing thread to the support surface and the successive layers of thread. The reinforcing thread is pressed against the support surface in a manner that exerts a pressure substantially perpendicular to the support surface at the point where the thread is deposited. The binder may be pre-applied to the support surface or it can be applied simultaneously with the reinforcement thread.

Abstract: Method and machine for producing multiaxial fibrous webs. A plurality of unidirectional sheets (30a, 30b, 30c) are superposed in different directions and they are bonded together. At least one of the unidirectional sheets is made by spreading a tow so as to obtain uniform thickness, width not less than 5 cm, and a weight of no more than 300 g/m2, cohesion being imparted to the sheet so as to enable it to be handled prior to being superposed with other sheets. Advantageously, the unidirectional sheets are made of carbon fibers and are obtained by spreading out large tows.

Abstract: A plurality of unidirectional sheets (30a, 30b, 30c) are superposed in different directions and they are bonded together. At least one of the unidirectional sheets is made by spreading a tow so as to obtain uniform thickness, width not less than 5 cm, and a weight of no more than 300 g/m2, cohesion being imparted to the sheet so as to enable it to be handled prior to being superposed with other sheets. Advantageously, the unidirectional sheets are made of carbon fibers and are obtained by spreading out large tows.

Abstract: A bias fabric is provided in that it is in the form of a cloth of length (L) and of finite width (l), being constructed by interlaced yarns (2, 3) extending in respective directions (D and d) that are oblique relative to the length (L), and each of which presents no knotting. The invention is applicable to engineering fabrics based on flat yarns.

Abstract: A woven fabric to be used in formation of a composite material includes multifilament warp and weft threads. Each of the warp threads and the weft threads have a total weight less than 80% of the weight of the fabric. The woven warp and weft threads have O twist/m and a torsion no greater than an original torsion of the threads before weaving. Each woven warp and weft thread has a width over the entire length thereof that is greater than or equal to an original width before weaving. The fabric is woven to have a given weight per unit area and a fiber volume ratio that is approximately constant throughout the fabric and that is satisfactory for use of the fabric in a composite material. The warp and weft threads of a yarn count that is greater than a yarn count traditionally used to achieve the fiber volume ratio for the given weight per unit area.

Abstract: A woven fabric to be used in formation of a composite material includes multifilament warp and weft threads. Each of the warp threads and the weft threads have a total weight less than 80% of the weight of the fabric. The woven warp and weft threads have 0 twist/m and a torsion no greater than an original torsion of the threads before weaving. Each woven warp and weft thread has a width over the entire length thereof that is greater than or equal to an original width before weaving. The fabric is woven to have a given weight per unit area and a fiber volume ratio that is approximately constant throughout the fabric and that is satisfactory for use of the fabric in a composite material. The warp and weft threads of a yarn count that is greater than a yarn count traditionally used to achieve the fiber volume ratio for the given weight per unit area.

Abstract: A multilayer textile article for the production of laminated materials has layers each consisting of a two-directional cloth, the layers being joined together by a third thread extending in a direction inclined to the direction in which the threads of the layers extend. According to the invention the third thread forms a continuous stitching (C), the stitching extending helically from one end of the layers to the other.

Abstract: The invention relates to a process for the production of hollow bodies of revolution formed from threads extending in three different directions, as well as to a machine for performing this process. The machining of a mandrel, the installation or implantation of retaining or locking rings on this mandrel, the winding and weaving of the threads in circumferential, longitudinal passages formed between the locking rings and the appropriate dimensional controls and checks are carried out on the same machine. On one side of the horizontal axis of the machine is provided a mobile support on which can be mounted the subassemblies for machining the mandrel, the implantation of the locking rings, winding and control, the weaving system being placed on the other side of the axis. In order the facilitate the weaving operations, the weaving carriage moves parallel to a fictitious generatrix joining the ends of the body, the weaving means being oriented perpendicular to said generatrix.

Abstract: An apparatus making it possible to fit retaining pins on a mandrel. The retaining pin arrives in the form of a continuous wire which is cut to the desired length by a wheel before being fitted in the mandrel. The end of the uncut retaining pin adjacent to the wheel is maintained in a gripper formed by two jaws. Simultaneously with the fitting of the cut retaining pin, a hole is made in the mandrel to permit the subsequent fitting of a retaining pin.

Abstract: A process for inserting points (38) in a mandrel (36) and a machine for performing this process. A working head (40) simultaneously ensures the insertion of a point and the making of a perforation (112) in the mandrel by means of a punch (94). The perforation is made in the same longitudinal row as the inserted point and towards the front with respect to the latter, in such a way that it is subsequently possible to guide a point following a rotation of one or more turns of the mandrel. The invention is applicable to the production of members or bodies of revolution made from three-dimensional material.

Abstract: A process for inserting points (38) on a mandrel (36) and a machine for performing this process. A working head (40) simultaneously ensures the insertion of a point and the making of a perforation (112) in the mandrel by means of a punch (94). The perforation is made in the same longitudinal row as the inserted point and towards the front with respect to the latter, in such a way that it is subsequently possible to guide a point following a rotation of one or more turns of the mandrel. The invention is applicable to the production of members or bodies of revolution made from three-dimensional material.

Abstract: A machine for the manufacture of rotational parts in a three-dimensional material is disclosed. A mandrel provided with rows of barbs is rotatably carried by the machine, whereby superimposed layers of threads are successively deposited in the longitudinal and circumferential corridors defined between the barbs. The machine additionally comprises a retractable member adapted to hold in place one extremity of a weft thread when the latter does not extend outside of the corresponding corridor, and a winding system which positions a holding thread in a circumferential corridor near the extremities of the weft threads to hold them in place when the retractable member has been retracted.

Abstract: The present invention relates to a process for manufacturing pieces of revolution made of three-dimensional material, of which the generatrix has at least one concave part, said process consisting in making a support mandrel provided with rows of pins defining therebetween longitudinal corridors and circumferential corridors, in disposing superposed layers of yarns in said corridors by winding and by filling, in densifying the assembly thus obtained, and, finally, in eliminating the support mandrel, wherein the longitudinal yarns are deposited in corresponding corridors and these yarns are maintained in the corridors at the level of said concave part. The invention also relates to a machine for carrying out this process.

Abstract: This invention relates to a body of three-dimensional fabric, a method of producing such bodies or parts of various shapes from three-dimensional fabric and also relates to apparatus for industrial performance of this method.