Month in the Patent Office

A ring 51 behind the cowl 1 of an aircraft engine defines a passage for air from the outside of the cowl and, by a venturi effect, aspirates air through the cowl 1. The ring 51 is radially extensible under the control of the pilot and normally forms a continuation of the cowl 1. Two mechanisms for operating the cowl are described. In one (fig. 6), each of the segments 8, 8 is carried at its extremities by levers 13, 14 and 28, the latter being secured to the axle 27 of an electric motor. The lever 13, 14 is connected for operation with the lever 28 by a toothed sector 26 engaging teeth 25 on a circular rack 24 having further teeth 23 adapted to operate a toothed sector 22 connected by a linkage 21, 19 to the lever 13, 14. In the other operating mechanism, the two segments 8, 8 arc guided to move diametrically outwards under the force of a fluid‐pressure jack. Flaps 31 ensure continuity between the fixed and moving parts, 7, 8 of the ring 51.