Improvements in and relating to jet reaction propulsion devices

摘要

613,989. Propelling aircraft. POWER JETS (RESEARCH & DEVELOPMENT), Ltd., BRAME, E., and JOHNSTONE, A. P. July 21, 1945, Nos. 18760/45 and 19342/46. [Class 4] [Also in Group XXVI] In an aircraft gas turbine fitted with a jet pipe having a nozzle end 14 for efflux of the working fluid, jet spoiling means associated with the nozzle end comprises at least one pair of pivotable jaw members having a crosssectional shape presenting a hollow body conforming to that of the nozzle end and, when they are in the non-spoiling position being disposed co-axially therewith to provide a wholly unimpeded flow path for the working fluid, but being movable to a jet-spoiling position where they form a baffle across but spaced from the nozzle end. The jaws 10, 11, Fig. 3, are pivoted to radius rods 22, 23 and operated by a push-pull rod 15 secured to. adjacent corners 45, 46. Forward movement of the rod sets the jaws across the end 14 of the nozzle and cowls 18, 19 on them give a reverse component to the jet. In another form the jaws are pivoted at 45, 46 and the radius links are connected to the push-pull rod, the cowls 18, 19 being omitted. As shown in Fig. 5, the jaws 20, 21 pivot about a single pin 20a and in their open position form part of the nacelle 38 as do extension flaps 29 pivoted to the jaws at 29a and secured to operating rods 27. These rods are connected to a nut 30 on a screwed rod 31 adapted to be rotated through a sprocket 32 by a chain encircling the jet pipe 14a and driven by an electric motor. Rearward displacement of the rod 27 turns the jaws to the spoiling position and disposes the flaps 29, to reverse the jet, as shown in the heavy chain lines. The jaws may form a continuation of the jet pipe and be provided with outer shields continuing the nacelle, the air flow induced between the nacelle and the jet pipe serving to cool the pipe and being deflected outwards by a flange on the end of the jet pipe. Alternatively the jaws, arranged to form a continuation of the jet pipe, taper rearwardly and so give some reverse thrust when in the jet-spoiling position.