摘要 |
A planet carrier for a compound planetary gear arrangement has four side plates supporting six pinion gears. One pair of side plates, supporting three of the pinion gears, have one of the other pair of side plates disposed axially between them. This allows the pinions to be in meshing relation between adjacent side plates which are each supporting three pinions, respectively. To complete the planetary arrangement, the outer side plates are sized to permit central access at respective sun gears and outer axial access at respective ring gears. The ring gears and sun gears do not encroach upon the meshing location of the pinion gears. With the judicious use of friction clutches and brakes and two input gear sets providing ratios, the compound planetary arrangement can be controlled to provide powertrains having from five forward speeds (the four friction devices) to seven forward speeds and two reverse speeds (with eight friction devices). Thus, the planetary arrangement can be utilized to provide a plurality of speed ratios, wherein the number of friction devices is one less than the total number of speed ratios.
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