GB468365A - Improvements in means for damping vibrations of aircraft fixed wings, or supporting surfaces having a limited pivotal movement - Google Patents

Abstract

468,365. Vibration-dampers; damping vibrations in aircraft parts, floors, and pipes ; mounting motors. ROUY, A. L. M. A. Dec. 30, 1935, Nos. 36012 and 36013. Convention dates, Dec. 29, 1934 and May 8, 1935. [Class 108 (iii)] [Also in Groups X, XXVI, and XXXIII] Fixed aircraft wings or aircraft supporting surfaces having a limited pivotal movement comprise at least one vibration-damping system arranged so as to destroy the energy tending to maintain the vibrations. The fluid-friction vibration-damper shown in Fig. 2 is preferably arranged at the free end of an aeroplane wing and comprises a mass in the form of a circumferentially-grooved piston 2 which is adapted to reciprocate against the action of springs 1 in a cylinder 7 and to force a liquid or gas through a valve-controlled pipe 8 connecting the ends of the cylinder. To prevent the piston knocking the ends of the cylinder the fluid resistance may be increased, as the piston approaches the end of its stroke, by the closing of the pipeopening by the piston, or the piston or cylinder ends may be formed, for example, of leather. Fig. 5 shows a modified construction fixed inside an aeroplane wing-spar by means of a bracket 21 and tightening collar 22, the springs 1 being of the flattened, double-conical type. Fig. 7 shows the invention applied to an aileron 23, the damping-device being pivoted between the free ends of arms 25 fixed to the aileron and being reciprocable in an aperture 26 in the wing. In another construction shown in plan view in Fig. 4, the mass 4, or members moving therewith, is or are carried by jaws 3 adjustably spring-pressed into frictional contact with guides 5 secured to the vibrating part, the contact surfaces being of steel and guaiacum respectively. It is stated that the energy absorbed by a device according to the invention may be dissipated in any form such as electrical, mechanical, or thermal. The Specification as open to inspection under Sect. 91 describes also means for damping vibrations in floors, particularly on ships. In one form, a member 32, Fig. 11 (Cancelled), projecting upwardly from one floor 34 is adapted to engage between spring-pressed friction plates mounted between cheeks 30 depending from an upper floor 31. The Specification also describes (a) means for damping vibrations in pipes, particularly oil and petrol pipes on aircraft, the connection between the piping and its support comprising relatively-displaceable frictional parts, or the piping itself being formed in a plurality of such parts, and (b) the application of the invention to motors, particularly aircraft motors, as shown in Fig. 5 (Cancelled), in which the motor casing 13 is resiliently connected to a cradle 14 spring-mounted on a support 15, friction or other dampers 17 being interposed between the cradle and support. A spring-controlled inertiamass 2 acting as a vibration-damper is mounted beneath the motor. This subject-matter does not appear in the Specification as accepted.