GB839999A - Improvements in or relating to helicopters - Google Patents

Abstract

839,999. Gas turbine plant. SUD-AVIATION SOC. NATIONALE DE CONSTRUCTIONS AERONAUTIQUES. May 3, 1957 [May 15, 1956; June 26, 1956], No. 14200/57. Class 110(3). [Also in Group XXXIII] Groups of one or more free turbine engines with built-in reduction gears are all coupled to drive a helicopter rotor shaft. In one layout, Figs. 3 and 4, a single front engine 18 is supported by a pair of side struts 26 and elastic joints 27 (one shown) and a tripod 28 at the rear. The engine drives a shaft 32 containing a freewheel 104 and universal joints 33, 34. The shaft is coupled through reduction bevel gears 30, 47 to an epicyclic gear (not shown) driving the rotor shaft. Two rear turbines 19, 20 are coupled to a common gear-box 36 driving a shaft 42 containing universal joints 43, 44 and driving a bevel gear 31 meshing with gear 47. Each rear turbine is supported at the front by struts 26a similar to struts 26, and at the rear by a support 46 for the gear-box 36. Alternatively, the engines may be supported by a pyramidal structure at the front, and two lateral struts at the rear, Fig. 11 (not shown). Other engine layouts of two, three, four or six engines are described. Splinec connections allowing axia expansion may connect the shafts to the engines Throttle controls for three engines are shown in Fig. 7 where individual controls 17a, 17b, 17c for each engine are coupled by cables such as 93 to the lower ends of three floating levers such as 95. The intermediate pivots of all three levers are movable by a twist grip control 105, and the upper ends of the levers are connected to the control mechanisms of the three engines respectively. Operation of one of levers 17a, 17b or 17c will affect the corresponding engine only, whereas operation of the twist grip will affect all three engines equally. Specification 790,876 is referred to.