GB610807A - Improvements in or relating to power transmission or drive systems - Google Patents

Abstract

610,807. Aircraft gun mountings. STEEL PRODUCTS ENGINEERING CO. Nov. 10, 1944, No. 22176. Convention date, Nov. 13, 1943. [Class 92 (i)] [Also in Group XXIV] In a shaft coupling applied. to an aircraft gun turret fire-control mechanism to provide an amount of self-protective firing cut-off proportional to the speed of gun traverse, a driving shaft 10, Fig. 1, rotating with the gun turret, carries a coupling chamber 40 in which are disposed vanes 45, Fig. 5, on a driven shaft 12 connected to the fire control mechanism.. The chamber 40 is divided into two operative compartments by stop members 55. With the shaft 10 stationary, the vanes are disposed centrally in the compartments under the action of a spring 62, Fig. 4, mounted on the chamber cover 41 so as to revolve with the driving shaft and having a tongued member 67 keyed to the driven shaft inserted between its free ends so that relative rotation in either direction between the shafts is resisted. Upon rotation of the coupling, a gear pump 17, 19 driven by the shaft 10 delivers oil to the compartments through passages 25, 27, Fig. 2, and an annulus 31 in the casing 15, passages 34, 35, Fig. 6, in the shaft 10 and passages 47, 48, Fig. 9, in the vane body 46, and exhausts it therefrom through passages 49, 50 in the vane body, passages 36, 37 in the shaft 10 and an annulus 32 and passages 28, 26 in the casing. The differential pressure thus set up on the opposite sides of the vanes causes them to rotate relative to the chamber and take up a position therein determined by the rate of escape of the oil round the vanes and by the restoring force of the spring 62. The stops 55 serve to limit the movement of the vanes, which are so arranged that the leakage round them at full deflection is sufficient to prevent the development of excess pressure in the system. The chamber 40 operates in an oil bath, replenished through a filler plug 72. If desired, only a single vane may be utilized and one of the stops dispensed with to provide a phase change up to approximately a full turn of the vane. As described, the phase of the driven shaft is always advanced relative to that of the driving shaft, but it may be retarded by reversal of the fluid connections from the pump. The coupling units may be duplicated, one being related to the motion of the gun in elevation and the other to its motion in azimuth.