Patent GB-585930-A (GB)
Title: Improvement in means for lubricating power transmitting mechanism
IPC: F16H57/04
Filed: 1944-04-06
Abstract: 585,930. Lubricating variable-speed toothed gearing. PACKARD MOTOR CAR CO. April 6, 1944, No. 6496. Convention date, April 19, 1943. [Classes 80 (i) and 80 (ii)] [Also in Group XXXIV] In an anti-sludge lubricating system for a high-speed planetary two-speed gear, particularly for driving an aircraft engine supercharger, a floating plain-bearing bushing 51, Fig. 3, of the planet-pinion shaft 49 is lubricated from the pressure-fed hollow sun-wheel shaft 28 through passages 62, 63, 65, 64, 67, 68, and the passages 67 in the rotating planetcarrier 47 communicate with an internal groove 66. Figs. 2, 3 and 5, in the internal bearing surface of the carrier, such groove extending over a part only of the circumference and being of sufficient circumferential length always to overlie at least two of the radial borings 68 in the floating bushing 51. Other borings 68 not registering with the groove 66 at any particular instant, will thus be closed to oil flow, and this is stated to obviate concentration of sludge from the centrifuged oil in the groove 66 tending to block the borings 68 such as might occur, it is suggested, if the groove 66 extended completely round the circumference. At the other end of the planet pinion shaft 49, a similar floating bushing 50 is lubricated from the radial borings 68 in the first bushing 51, through complementary circumferential grooves 69, 70 in the bushing and shaft, borings 71, an annular chamber formed by a spun sleeve 52, borings 76, circumferential groove 77 and radial borings 78. Floating bushings 101, 56 for the sunwheel shaft 28 and 55 for the planet-carrier 47 are supplied through shaft passages 100 and 62, 65 respectively. Lubricating means for the gear teeth are also described below. In the complete drive shown in Fig. 1, three planetary trains, each of the kind shown in Fig. 3, are grouped about, and drive a central shaft 14 mounting the supercharger impeller 15, the planet-carriers 47 of each train being driven from a central driving shaft 13 through a spur pinion 27 meshing with a common central wheel 20. The driven annulus 26 has integral external teeth driving a common central pinion 21 on the driven shaft 14, which is stated to rotate at over 24,000 r.p.m. A oneway roller clutch 33 between the sun-wheel shaft 28 and carrier 47, provides a direct solid drive through the planet gear, and overruns when the sun-wheel shaft 28 is held by an hydraulically-actuated friction brake 35, to impart a speed-increase to the driven annulus 26. Hydraulic pressure reaches the brakepistons 39 through a common oil-servo duct 42 in a wall of the gear casing, whilst lubricating oil reaches the hollow sun-shaft 28 through passages 57, 58, 59 from a common circumferential pressure-fed main 60 in the walls. The brake and control system form the subjectmatter of Specification 577,652. The planetary gear-teeth are lubricated from the bushing passages 64, Fig. 3, through passages 80 in the. carrier, having slotted tangential outlets 81, Fig. 9. Relief outlets 79 at the periphery of the carrier 47 prevent accumulation of centrifuged oil. The teeth of the final spur pair 26, 21 are directly lubricated through passages 75, Fig. 1, at roots of the tooth spaces of the wheel 26, the passages being fed centrifugally by oil in the carrier 47 escaping from the outlets 81. The passages 75 are so spaced circumferentially on the wheel 26 that each of the 30 teeth of the pinion 21 receives a direct supply twice for each ten revolutions of the wheel 26, which has 63 teeth. For this purpose the passages 75 are spaced circumferentially 12, 8, 12, 11, 9 and 11 teeth.