Patent ID: 7421921
Filing Date: 2008-09-09
Classification: F16H,Y10T

Abstract:
1. A parallel axes type automatic transmission comprising: a first input shaft having m wet multiplate clutches and m drive gears rotatably mounted, wherein m represents a quantity of clutches and of gears, and is an integer not less than 2; a second input shaft having n wet multiplate clutches and n drive gears rotatably mounted, wherein n represents a quantity of clutches and of gears, and is an integer greater than m and not less than 3; a third input shaft having at most m wet multiplate clutches and at most m drive gears rotatably mounted; and an output shaft having a fixed final drive gear and a plurality of fixed driven gears; said first, second, and third input shafts being arranged at different elevations such that said second input shaft is arranged at a highest elevation, said first input shaft is arranged at a middle elevation, and said third input shaft is arranged at a lowest elevation, wherein said second input shaft has a largest value for a lubrication flow coefficient, said first input shaft has a middle value for said lubrication flow coefficient, and said third input shaft has a smallest value for said lubrication flow coefficient, wherein said lubrication flow coefficient is the product of (1) a speed reducing ratio of an input shaft selected from said first, second and third input shafts with respect to said first input shaft, and (2) the number of wet multiplate clutches provided on said input shaft selected from said first, second and third shafts.