GB694861A - Improvements in change speed gearing of the double planetary type - Google Patents

Abstract

694,861. Change-speed gearing. DAIMLERBENZ AKT.-GES. May 22, 1950 [May 20, 1949], No. 12699/50. Class 80 (ii). In epicyclic change-speed gearing B comprising stepped planets meshing with two suns 16, 17 and with an annulus 20, the planet carrier 21 is the driven member, the annulus can be braked at 26 and the two suns can be connected simultaneously to the driving member 5 so as to be rotated at different speeds. As shown, the smaller sun 17 is adapted to be clutched at 39 direct to the shaft 5, and the larger sun 16 is connected to the planet carrier 11 of an auxiliary two-speed epicyclic gear A, the annulus 8 of which is connected to shaft 5 and the sun 10 of which is adapted to be braked at 13 or clutched at 12 to the carrier 11. The sun 16 is adapted to be braked at 15, and the sun 17 can be braked at 34 or clutched at 37 to the carrier 21. At least six forward speeds and one reverse speed are obtainable. For first speed, brakes 13 and 26 are engaged, so that both gears A and B step down the speed in series. For second speed, clutch 12 and brake 26 are engaged, so that gear A is solid and gear B steps down, in series. For third speed, clutch 37 and brake 13 are engaged, so that gear A steps down and gear B is solid, in series. For fourth speed, brake 13 and clutch 39 are engaged, so that gear A steps down to sun 16 and sun 17 is driven direct from shaft 5. For fifth (direct) speed, any two or all of the three clutches 12, 37, 39 are engaged, so that both gears A and B are solid. For sixth (overdrive) speed, clutch 12 and brake 34 are engaged, so that gear A drives solid to sun 16 and sun 17 is arrested. For reverse, brake 15 and clutch 39 are engaged, so that sun 16 is arrested and sun 17 is driven direct from shaft 5. Further forward speeds may be obtained by (a) engaging brakes 13 and 34, so that gear A steps down to sun 16 and'sun 17 is arrested, and (b) engaging brake 26 and clutch 39, so that sun 17 is driven direct from shaft 5 and annulus 20 is arrested. Still further speeds may be obtained by providing a second annulus meshing with the smaller planet wheels and capable of being braked. The shaft 5 may be driven from the engine shaft through a fluid coupling adapted to be locked by a clutch which may be speedcontrolled.