Eight-speed automatic transmission has five torque-transmitting clutches that are engageable to the gears, carriers and transmission housing in combinations of three to establish eight forward speed ratios and one reverse speed ratio

摘要

Four planetary gear sets (14,16,18,20) and three interconnecting shafts (42,44,46) are used. First shaft interconnects the ring gears (14A,18A,20A) of first, third and fourth sets. Second shaft interconnects the planet gear carrier (14B) of first set with transmission housing (50). Third shaft interconnects the sun gears (14C,16C) of first and second sets. Five torque-transmitting clutches (26,28,30,32,34) are engageable to the gears, carriers and housing in combinations of three to establish eight forward speed ratios and one reverse speed ratio between input shaft (12) and output shaft (22).