GB735593A - Improvements in and relating to epicyclic gearboxes - Google Patents

Abstract

735,593. Toothed gearing. BRITISH THOM. SON-HOUSTON CO., Ltd., and METALASTIK, Ltd. March 10, 1954 [March 16, 1953], No. 7189/53. Class 80 (1). The reaction annulus 2 of an epicyclic sun - planets - annulus gear train is located with respect to an outer fixed casing 1 by two or more links 3 which are substantially tangential to a circle concentric with the pitch circle of the annulus and are resiliently connected to ears on the annulus and casing through rubber-bushed pins 7 so that the axis of the annulus has limited freedom for radial and tilting movements to centre the annulus on the planets and to maintain uniform pressure over the face width of the teeth, while a high resistance to rotation of the annulus is maintained. Each rubber bush, Fig. 2 (not shown), is mounted between two metal sleeves to which it may be bonded, and if natural rubber is employed, oil-resistant synthetic rubber seals may be provided at each end of the bush. In a modification of the four-link arrangement shown in Fig. 1 one of the casing-ears is dispensed with and two of the four links are turned through 180 degrees so that two links share a common ear on the casing. In a further modification the four links shown in Fig. 1 are duplicated so that each of four ears on the annulus has two links disposed in opposite tangential directions and each of four ears on the casing receives two substantially perpendicular links. According to Fig. 5, three ears are provided on both the annulus and the casing and are coupled by two end-connected links 18 and a single link 17 having a resilient connection at its mid-point. In a modification of this arrangement the annulus is supported by only two single links whose mid-points are resiliently connected to diametrically opposite ears on the annulus. Specifications 581,464 and 732,436, -[both in Group XXXII], are referred to.