GB649412A - Improvements in rotary compressors and engines - Google Patents

Abstract

649,412. Rotary engines and compressors; gas turbines. STEVENS, A. H. (Wright Aeronautical Corporation). Oct. 4, 1948, No. 25803. [Class 110(ii)] [Also in Group XXII] A rotor 10 is provided with helicospiral vanes 16 which. with abutments 43 on discs 42, form working chambers diminishing in capacity from the rotor periphery radially inwards. The vanes 16 may be hollow, Fig. 1, and have cooling fluid passed through them. A stator 22, supporting the discs 42, is toric-shaped to fit closely to the vane tips, between the discs. The latter ,are driven by main gears 74, 72 frcm the main shaft 76, and from a shaft 66 coupled to the discs through bevel gearing. The stator 22 is built up of segments 32, which carry the discs and their driving mechanism, and segments 34, surrounded by a band 38 secured by bolts 40. The disc axes are tangential to the pitch circle 14 of the toric stator t. The disc shafts 48, 78, carry end flanges 50 and nuts 52 to clamp nut members 54, 56 and the bevel gears in position. Each disc 42 is formed in two halves to facilitate assembly, the halves being secured between the members 54, 56 by screws 62. Each bevel gear 58 meshes with a bevel gear 64 formed integrally with the shaft 66 and gears 60, 84 mesh together. In the construction shown the speed ratio between the rotor 10 and each disc 42 is 12 : 8 to prevent contact between the vanes 16 and disc teeth 43. Labyrinth packings 112, carried by walls 33, 35, minimize leakage of working-fluid, or fluid being compressed, radially inwards. When operating as a compressor the rotor 10 turns anti-clockwise, Fig. 3, and fluid which enters an annular inlet 24 is compressed in the diminishing chambers and discharged through an annular outlet 26. The compression ratio may be varied by varying the number of abutment discs, with increase in the number of vanes 16 and/or increase in the angle subtended by each vane about the rotor axis between the peripheral and minimum diameter of the rotor. Lubricating oil, for the bearings and gears, is supplied through ducts 94, 96, 98, 100. Seals 102 prevent leakage of oil to the discs 42. To balance the axial thrust on the rotor 10, fluid under pressure passes through openings 102 into a chamber 104. Two rotors may be arranged back-to-back for balancing purposes. When the apparatus operates as an engine, high-pressure fluid is supplied through the duct 26. Cooling air may be admitted into a shaft extension 76 and flows into the vane interiors through holes 108 and discharged through holes 110. Where the compressor supplies a gas turbine, compressed air collected by a manifold 114 may be led to passages in or between the turbine blades for cooling purposes. As a rotary engine the apparatus may be used as a starter for aircraft power plants, such as gas turbines. Means to machine the rotor disc, and form the vanes, are described in the Specification.