GB873029A - Two-speed driving mechanisms - Google Patents

Abstract

873,029. Variable - speed gear ; friction clutches; toothed gearing. U.S. INDUS TRIES Inc. Sept. 15, 1958 [Jan. 10, 1958], No. 29439/58. Classes 80 (1) and 80 (2). A two-speed epicyclic gear for metal drawing presses comprises a sun 17 fast with an input flywheel 12, a permanently stationary floating " ring-gear 27, and a planet carrier 21, and is controlled by selective energization of high and lowspeed friction clutches 9, 10 which connect the flywheel 12 or planet carrier 21, respectively, to an output shaft 2 for direct or reduced drive. The ring gear 27 floats radially in a fixed casing 47 by an Oldham ring mounting 30 to prevent misalignment of the gears when the shaft 2 is deflected. The air engaged friction clutches 9, 10 are made as detachable units fitted between the flywheel 12 and an end-plate 14 bolted thereto at 15 and between the plant-carrier 21 and an end-plate 23 bolted thereto. Both clutches are identical and comprise a driven plate 55 fast with the shaft 2 and which may be clamped between a pneumaticallyoperated piston 71 and the respective end-plate. The plate 55 has circular openings 60 recessed at 67, Fig. 6, which receive aluminium discs 62 faced with friction material 65, 66 and bored radially at 68 to receive pins 69 the heads 70 of which engage the recess 67, thus preventing rotation of the discs 62 in the holes 60 whilst permitting relative axial movement. The pistons 71 have extensions 73 which project between the bolts 15, 24 and are axially slidable on bolts 74 in the respective flywheel 12 or planet carrier 21. The low-speed clutch 10 is engaged by supplying pressure air to a cavity 78 sealed by a diaphragm 79, from a supply 88 through an air seal 85 (of the type described in Specification 847,749) and duct 83, and the high-speed clutch 10 is similarly engaged by a supply 93. The gear may be lubricated by supplying oil at 98.