GB478427A - Improvements in and relating to devices for accelerating aircraft for launching purposes - Google Patents

Abstract

478,427. Catapult for launching aircraft. MITCHELL, C. C. May 18, 1936, No. 14074. [Class 4] A device for accelerating aircraft for launching comprises at least one cylinder or duct having a longitudinally extending slot or opening in the wall thereof, in which cylinder or duct fluid pressure can be generated or introduced, a piston carrying a pin or platelike member projecting through the slot or opening and a tlexible belt or the like located within the cylinder or duct and by which the opening can be sealed. In one form, Fig. 1, a long cylinder a closed by end covers b, b is provided with a narrow slot c, Fig. 3. A piston comprises end elements d interconnected by girders e, elements d being provided with packing devices. Between girders e are mounted pulleys f, f <1>, f<2> pulley f <1> being at a lower level than the others. A flexible belt or packing strip g passes through covers b at each end of the cylinder and is tensioned by spring means. Belt g extends along slot c to pulley f, passes beneath pulley f which is peripherally grooved, then over pulley f<2> thence along the slot to the other end of the cylinder. The sides of the slot are tapered slightly and the belt is of vee-section. A bracket h secured to girders e carries a fm i passing through the slot and attached to means for communicating movement of the piston to the aircraft or acting directly on the craft. The piston carries rollers j, j j<1> at each end. Fluid pressure is admitted to cylinder a by a port k. An air exhaust port l, a transfer duct for effecting braking and a safety valve bl are provided at the remote end of the cylinder. Valves may be provided in port l and duct m to enable the piston to perform the return stroke under fluid pressure. Alternatively, the device may be made capable of launching an aircraft in either direction by duplication of the ports and ducts. Where the piston is to be purely single acting, the leading pulley is removed and the leading end of the piston omitted or cut away to permit it to pass over the belt lying on the bottom of the cylinder or duct. In a modification, Figs. 5 and 6, two cylinders are arranged side by side and the pistons are interconnected by members n attached to pins i, i<1> so as to constitute a launching carriage. The pistons are provided with two grooved pulleys p, p in place of the single pulley f<1> of Fig. 1, and have additional rollers q, q<1> bearing on the cylinder wall. Means may be provided for introducing fluid under pressure at an intermediate point during the working stroke. The cylinder may be other than circular in cross-section.