摘要:
The invention provides a balance bar twin blade hub. A beam is formed of a tube made from a composite material of evolutive form whose section is cylindrical at its end on the blade side and progressively elliptical as far as its central connection part. It is connected to a support stirrup 2 conical stratified stops 4 forming balance bar bearings identical to the conical stratified stops forming the centrifugal force take up and angle of attack bearings providing the connection between the blade 16 and the beam.
摘要:
The blade has its lower-surface and upper-surface skins of its shell, its front and rear filling bodies and its spar made of a composite material having the same thermoplastic matrix, preferably made of PEEK, reinforced preferably with carbon fibres. The spar is extended outside the shell by an integrated rooting part with linkage attachment, in a loop or laminate, in the same thermoplastic composite. The method consists in assembling, by melting, under pressure, all the thermoplastic composite components of the blade, in a single step after manufacturing these components in the form of prefabricated elementary pieces.
摘要:
The blade has its lower-surface and upper-surface skins of its shell, its front and rear filling bodies and its spar made of a composite material having the same thermoplastic matrix, preferably made of PEEK, reinforced preferably with carbon fibres. The spar is extended outside the shell by an integrated rooting part with linkage attachment, in a loop or laminate, in the same thermoplastic composite. The method consists in assembling the spar with the skins, after manufacturing these components in the form of prefabricated elementary pieces, by injecting under pressure a fluidized thermoplastic composite with short reinforcing fibres moulding the filling bodies.
摘要:
The flexible girder made of composite materials and with high energy absorption is in the form of an elongate box of laminated structure comprising two rigid flanges (6,7) connected by two webs (9) which have aligned apertures (13). A deformable energy-absorbing block (14') is arranged between the two flanges (6,7) at the apertures and comprises a block of an elastomeric material (15). The block (14') absorbs the buckling deformation energy of the flange (6) which is subjected to compressive stress during flexion of the girder, by resting on the other flange (7) which is subjected to tensile stress. The block (14') controls the buckling of the flange (6) and only gives back part of the energy absorbed. Application to the equipment in particular of skid landing gear for helicopters and tail skids for aircraft.
摘要:
The invention relates to a process and an apparatus for the metallic impregnation of a substrate that is in the form of a web of conductive fibres, in which the said substrate is placed in an inert atmosphere that is under partial vacuum (chamber 1), a potential difference is created between the said substrate (cathode) and a metal for impregnation in the said atmosphere, the metal for impregnation is supplied in molten form into the said atmosphere and is maintained at its vaporization temperature by heating.The invention is of use in the manufacture of semi-finished products for the aeronautical industry.
摘要:
The semi-finished product according to the invention consists exclusively of liquid crystal thermoplastic polymers (LCP), whereof at least one first liquid crystal thermoplastic polymer (LCP) is in the form of fibers (18) and has a given melting point, and whereof at least one second liquid crystal thermoplastic polymer (LCP) (16) has a melting point below that of the first LCP. This semi-finished product is in particular a fabric. By simply heating under pressure at a temperature equal to the melting point of the second LCP, followed by cooling, a composite material with improved mechanical and physicochemical performance characteristics are obtained.
摘要:
The invention concerns laminated stops of curved shapes, particularly for helicopter rotors. The stop has an inner fitting and an outer fitting connected by cupped elements of a resistant and rigid material alternating with layers of flexible material. The layers of flexible material increase in thickness from their centers outwardly, and the mean thickness of the flexible layers increase from the inner fitting to the outer fitting.