Patent RU-2626523-C1 (RU)
Inventor: ESKIN IZOLD DAVIDOVICH
IPC: F01D5/26
Filed: 2016-06-08
Granted: 2017-07-28
Abstract: FIELD: ventilation. 
     SUBSTANCE: proposed hollow wide chord fan blade, consisting of a shell made of a sheet of a titanium alloy, and heavy-duty supporting elements rigidly connected to it: plate girder, made of a titanium alloy, and others, made of unidirectional fiber metal matrix material of high composite modulus. Wherein n+1 heavy-duty supporting elements are made in the form of "swallowtail" locks and are placed between the other n heavy-duty supporting elements and on the edges of the blade lock, n-1 heavy-duty supporting elements, made of composite material, have a locking portion formed as a "swallowtail", and disposed within the shell portion in the form of a rod with a constant or gradually narrowing towards the end of the blade quadrangular cross-section, with a side or sides being in contact with the shell and following its shape. All the supporting elements are fixed to each other and the shell through the locking portions by means of diffusion welding at the temperature and pressure, and parts, located inside the shell, are connected with the shell. The plate girder consists of a locking portion made in the form of a "swallowtail" blade lock, made in one piece with a central rod having a box-shaped quadrangular cross-section, columns with a transverse quadrangular cross-section, with sides fastened with a shell and following its shape. Between each column and the central plate girder rod there is a rectangular slot. Each slot is embedded in the locking portion of the side member; in each of these two slots there is a smooth, steel, hardened or cold worked ground tape, and on the plate girder rod there is a smooth, steel, hardened or cold worked ground tape with grooves along the arc of the circle at one side of the tape. In each slot between the smooth tape and the insert strip with the required interference along the corrugation peaks δ>Y ∂ , where Y ∂  is the allowable deformation of the compression of the package corrugation in mm, so a multi-span package, assembled "corrugation into corrugation" from one, two or more steel, hardened or cold-worked ground corrugated tape is placed so that the corrugations of the package resting on the insert tape are placed in its And the tops of the corrugations are supported by grooves in their plane of symmetry, and ƒ≥Y ∂ +h, where ƒ - the arrow of the crest of the corrugation and h is the depth of the groove of the insert tape. Flanges are made on the free end of the plate girder rod. An insert tape is supported on each flange by a bent end, and a smooth tape is bent to the end of the column and the bent end rests on the bent end of the insert tape so that when the blade oscillates, mutual elastic slippage occurs of the bent ends of these tapes with dry friction. Corrugated tapes of the package, smooth tapes and insert tapes are made of heat-resistant stainless steel, which does not lose its elastic properties at 600°C, and the contacting surfaces of these tapes are covered with a wear-resistant coating that retains its protective properties at this temperature. 
     EFFECT: high strength and static rigidity that persists or accrues during the process cycle, with a highly efficient damping device that reduces dynamic stresses in the blade during impact and vibration to a safe level in all working conditions of the aircraft engine and increases the life and reliability of the fan. 
     11 cl, 9 dwg