Abstract: The invention relates to the field of aerial propellers, in particular the field of variable-pitch propellers, specifically for unducted fans. More specifically, the invention relates to a pivot (15) for a blade (14) of a propeller (3a, 3b), the pivot including at least a proximal portion (15a) made of metal and suitable for being retained in a radial orifice of a propeller hub, while being capable of turning in said orifice about a longitudinal axis (Z) of the pivot (15), and a distal portion (15b) including a receptacle (20) suitable for retaining a blade root, and at least one arm (17) of organic matrix composite material extending laterally relative to said longitudinal axis (Z) and supporting a flyweight (16).

Abstract: The invention relates to the field of aerial propellers, in particular the field of variable-pitch propellers, specifically for unducted fans. More specifically, the invention relates to a pivot (15) for a blade (14) of a propeller (3a, 3b), the pivot including at least a proximal portion (15a) made of metal and suitable for being retained in a radial orifice of a propeller hub, while being capable of turning in said orifice about a longitudinal axis (Z) of the pivot (15), and a distal portion (15b) including a receptacle (20) suitable for retaining a blade root, and at least one arm (17) of organic matrix composite material extending laterally relative to said longitudinal axis (Z) and supporting a flyweight (16).

Abstract: The invention relates to the field of aerial propellers, in particular the field of variable-pitch propellers, specifically for unducted fans. More specifically, the invention relates to a pivot (15) for a blade (14) of a propeller (3a, 3b), the pivot including at least a proximal portion (15a) made of metal and suitable for being retained in a radial orifice of a propeller hub, while being capable of turning in said orifice about a longitudinal axis (Z) of the pivot (15), and a distal portion (15b) including a receptacle (20) suitable for retaining a blade root, and at least one arm (17) of organic matrix composite material extending laterally relative to said longitudinal axis (Z) and supporting a flyweight (16).

Abstract: A method of braiding reinforcing fibers on a mandrel (8) with a machine having a ring (9) carrying at least two series of reels of fibers, by moving the mandrel at a predetermined forward speed while moving the two series of reels along the ring (9) so that they cross while rotating in opposite directions and at a predetermined speed of rotation about an axis (AX) of the ring. The braid is formed on the mandrel (8) in the vicinity of a region of convergence (R) of the fibers that together define a conical shape (C). The method comprises: a step of reconfiguring the machine in which the angle (a2) at the apex of the cone (C) defined by the fibers takes on a new value (a2); and a step of restarting braiding in which the movement of the reels along the ring (9) and the forward movement of the mandrel (8) are re-established with a new speed of rotation and a new speed of advance.

Abstract: The invention relates to the field of aerial propellers, in particular the field of variable-pitch propellers, specifically for unducted fans. More specifically, the invention relates to a pivot (15) for a blade (14) of a propeller (3a, 3b), the pivot including at least a proximal portion (15a) made of metal and suitable for being retained in a radial orifice of a propeller hub, while being capable of turning in said orifice about a longitudinal axis (Z) of the pivot (15), and a distal portion (15b) including a receptacle (20) suitable for retaining a blade root, and at least one arm (17) of organic matrix composite material extending laterally relative to said longitudinal axis (Z) and supporting a flyweight (16).

Abstract: The invention relates to a method for the operation of a plaiting machine (1) that comprises a ring (2) carrying fiber spools (3) for plaiting layers (16, 22) of fibers (3) about a mandrel (13, 17) carried by a carrier (12) capable of movement along the axis (AX) of the ring (2), wherein after plaiting the fibers (3) are cut in order to withdraw the mandrel (13, 17), and that comprises: a hub (5, 6; 18) carried by the carrier (12) and secured to the mandrel (13; 17) while being mounted upstream therefrom; an operation for tightening the fibers (3) around the hub (5, 6; IS) with a link (11, 14) surrounding said fibers (3) after the mandrel (13, 17) has passed through the ring (2); and in which the fibers (3) are cut between the mandrel (13, 17) and the hub (5, 6; 18) before withdrawing the mandrel (13, 17).

Abstract: A method of fabricating a composite material part such as a link. The method comprises the successive operations of applying reinforcing fiber layers (14a, 14b, 14c) that are braided around a mandrel over all or part of the length of the mandrel, the layers being superposed one on another. The method includes a step of cutting an intermediate reinforcing fiber layer (14a, 14b, 14c) after it has been applied, a step of withdrawing a cut portion prior to applying the following braided layer (14b, 14c), thereby locally building up an extra thickness of reinforcing layers on each portion of the cut layer that has remained in place, the extra thickness constituting local reinforcement of the part. Resin is subsequently injected into the various braided layers prior to the resin being polymerized in order to prepare a blank. The method applies in particular to the field of aviation.

Abstract: The invention relates to a method of braiding reinforcing fibers on a mandrel (8) with a machine having a ring (9) carrying at least two series of reels of fibers, by moving the mandrel at a predetermined forward speed while moving the two series of reels along the ring (9) so that they cross while rotating in opposite directions and at a predetermined speed of rotation about an axis (AX) of the ring, the braid being formed on the mandrel (8) in the vicinity of a region of convergence (R) of the fibers that together define a conical shape (C), the method being characterized in that it comprises: a step of reconfiguring the machine in which the angle (a2) at the apex of the cone (C) defined by the fibers takes on a new value (a2); and a step of restarting braiding in which the movement of the reels along the ring (9) and the forward movement of the mandrel (8) are re-established with a new speed of rotation and a new speed of advance.

Abstract: The invention relates to a method for the operation of a plaiting machine (1) that comprises a ring (2) carrying fiber spools (3) for plaiting layers (16, 22) of fibers (3) about a mandrel (13, 17) carried by a carrier (12) capable of movement along the axis (AX) of the ring (2), wherein after plaiting the fibers (3) are cut in order to withdraw the mandrel (13, 17), and that comprises: a hub (5, 6; 18) carried by the carrier (12) and secured to the mandrel (13; 17) while being mounted upstream therefrom; an operation for tightening the fibers (3) around the hub (5, 6; IS) with a link (11, 14) surrounding said fibers (3) after the mandrel (13, 17) has passed through the ring (2); and in which the fibers (3) are cut between the mandrel (13, 17) and the hub (5, 6; 18) before withdrawing the mandrel (13, 17).

Abstract: A method of fabricating a composite material part such as a link. The method comprises the successive operations of applying reinforcing fiber layers (14a, 14b, 14c) that are braided around a mandrel over all or part of the length of the mandrel, the layers being superposed one on another. The method includes a step of cutting an intermediate reinforcing fiber layer (14a, 14b, 14c) after it has been applied, a step of withdrawing a cut portion prior to applying the following braided layer (14b, 14c), thereby locally building up an extra thickness of reinforcing layers on each portion of the cut layer that has remained in place, the extra thickness constituting local reinforcement of the part. Resin is subsequently injected into the various braided layers prior to the resin being polymerized in order to prepare a blank. The method applies in particular to the field of aviation.