GB469473A - Improvements in shock-absorbing struts for aircraft undercarriages - Google Patents

Abstract

469,473. Shock-absorbers. FAUDI, F. Nov. 23, 1935, No. 32548. [Class 108 (iii)] In a shock-absorbing strut for aircraft undercarriages employing highly-compressed air as the shock-absorbing medium, in order to enable the strut to respond to shocks occurring when the aircraft is moving on the ground in an unloaded or lightly - loaded condition, a spring is arranged in the strut to oppose the force exerted by the compressed air. As shown, the strut comprises an outer cylinder B, connected to the aircraft, in which slides a piston A having a tubular rod D adapted to carry a landing-wheel, skid, float, &c., the spring E being arranged in the annular space J between the cylinder and rod and abutting at its upper end the piston A and at its lower end packing C which closes the annular space J. On extension of the strut the compressed air in chamber G acts as a damping medium. For this purpose openings H in the piston are controlled by a spring-pressed, apertured valve F so that when the strut is compressed the valve F opens and air flows into the annular space J, while, when the strut is extended the valve F is closed and the air passes back to the chamber G only through the restricted apertures in the valve. When the aircraft is being flown, the piston may abut a stop before the spring E is compressed sufficiently to counter - balance the pressure of the compressed air. The Specification contains a certain amount of theoretical discussion illustrated by graphs. Specifications 25033/06 and 28283/08, [both in Class 108], are referred to.