GB546630A - Improvements in bevel-gearing - Google Patents

Abstract

546,630. Toothed gearing. BRISTOL AEROPLANE CO., Ltd., FEDDEN, A. H. R. BUTLER, L. F. G., THOMAS, F. M., and PRICE, P. R. Jan. 17, 1941, No. 702. [Class 80 (i)] [Also in Group XXXIII] Consists, in a bevel-gear transmission, of the combination with a driving bevel and a driven bevel gear meshing with it, of a second driving connection between them through two idler gears. In a gear train for an airscrew drive in which the airscrews are spaced away laterally from the engine or engines, a driving shaft 10 is flexibly coupled at 11 to a shaft 12 mounted in bearings 13 in a casing 14 and carrying a bevel pinion 15. This meshes with a bevel wheel 16 on a shaft 17 mounted in bearings 18 and flexibly coupled at 19 to a driven shaft 20. The inner end of shaft 12 is carried by a bearing 21 in a housing 22 supported by webs in casing 14. According to the invention a second bevel wheel 23 and a bevel pinion 26, both idlers, are incorporated in the drive. The wheel 23 is mounted on a short shaft 24 carried in bearings 25 coaxial with shaft 17 and the pinion 26 is coaxial with the pinion 15. With this arrangement, tooth loading is reduced with a consequent reduction of tooth dimensions and weight of gear train. In a modified construction, the driven shaft is rotated oppositely to that in Fig. 1, by arranging the wheel 16 to engage the pinion 15 on the opposite side to that shown in Fig. 1, the shaft of this wheel extending across the axis of the pinion 15 and passing through the short hollow shaft of the corresponding idler wheel. In order to provide a satisfactory distribution of tooth loading, the bearings for the pinions 15 32. Fig. 3, are of a type which will permit of slight axial movement and these two pinions are coupled together by a tie-member 35. Fig. 3, which engages each of them by a radial and thrust bearing 36 so that they move in unison. In Fig. 3, means are also shown for lubricating the gear train comprising a gear-pump 37 driven by a bevel gear 38 which receives a drive from the gear wheel 31 and the wheel opposite thereto. Two or more spaced idler pinions may be used. To drive two airscrews in opposite directions from the same engine, one of each kind of gearing would be employed.