GB707357A - Improvements in or relating to self lubricating gear drive unit - Google Patents

Abstract

707,357. Gas turbine plant; elastic-fluid turbines; stuffing-box substitutes. THOMPSON PRODUCTS. Inc. Aug. 22, 1952, No. 21119/52. Classes 110(3) and 122(5) [Also in Group XXXIV] A self-lubricating gear drive unit which may be driven by a gas turbine, comprises a gear chamber adapted to receive a charge of lubricant, and info which extends an end portion of a shaft journaled in bearings, the shaft being provided with a lubricating passage communicating with the bearings and opening axially outwardly at the end portion of the shaft, gear means on said end portion, and baffle means in the gear chamber at the end of the shaft to collect lubricant splashed by the gears, for direction into said lubricating passage. In the construction shown, a casing 10 is in two parts 12, 14. connected together to form a gear chamber C containing gears 50, 58 mounted on a shaft 52, and engaging, respectively, a gear 26 on a shaft 22 and a gear 60 on a shaft 62. The shaft 22 is driven by a turbine rotor 32, the blades 32b of which are supplied with fluid, for example air, under pressure conveyed through a shroud 42 and through openings 38c in a nozzle ring member 38. The shaft 22 has an axial passage 84 extending from the inner end of the shaft to a radial passage 84a to convey lubricant to the bearings 24. The lubricant is contained in the gear chamber C which is provided with a baffle 78 formed as shown in Fig. 2, with slots 78a, 78b intersecting at a point opposite the passage 84. As the gears rotate oil is splashed against the walls of the chamber and is partly collected by the baffle, from which it is drawn to the bearings through the passages 84, 84a as the shaft 22 rotates. A similar arrangement is made for lubricating the bearings 64 of shaft 62. This shaft has a splined end for driving connection to an engine accessory, for example a fuel pump of a jet-propulsion aircraft engine. Leakage of lubricant along shafts 22, 62 is prevented by sealing means 30, 72 constructed as shown in Fig. 4. A sheet metal sleeve 188 press-fitted over part of the shaft 22 has a projection 188a with a driving connection to a ring 190. The ring is engaged by a graphiteimpregnated ring 100 carried by a spring-pressed diaphragm 196. The diaphragm acts against the outer surface of an apertured wall 194 welded to a casing 192 which is secured to a casting 12. Synthetic rubber sealing rings 102, 104 are provided which together with the ring 100 completely seal the shaft 22 and casting 12.