BLADE SPAR OF AERODYNAMIC MODEL OF PROPELLER AND METHOD OF ITS MANUFACTURE Russian patent published in 2018 - IPC B64C27/473 

FIELD: aircraft engineering.

SUBSTANCE: invention relates to structures and methods for manufacturing of propeller blades. Blade spar of the aerodynamic model of the propeller made of composite polymeric materials consists of upper and lower shaped caps connected with a filler. Filler consists of front, rear, central root inserts and a central insert of the main part. Front and rear inserts consist of shells in the form of a channel, filled with a light foamed polymer material. Thickness of the spar cap is 0.1÷0.2 of the spar width, and the width is from 0.5 to 0.85 of the blade chord length at a distance from the shank of 0.1÷0.2 of the blade length. Along the entire length of the spar the thickness of the caps gradually decreases to 0.02 of the width of the spar, and the width of the caps gradually decreases to 0.45÷0.55 of the blade chord length. Method for manufacturing the spar includes the manufacture of the filler, the overlay on the front and rear inserts of several layers of fabric impregnated with a polymer binder, and the pressing procedure. Sequence of laying and the direction of fabric fibers depend on the specified parameters of strength and stiffness of the spar.

EFFECT: invention enables to control the balancing and stiffening properties of the blade.

8 cl, 12 dwg