Multi-speed gearbox

A multi-step reduction gear in planetary construction, especially an automatic transmission for a motor vehicle, including a drive shaft (1) and an output shaft (2), which are arranged in a housing (G), first, second and third single rod planetary gears (P1, P2, P3), at least seven rotational shafts (1, 2, 3, 4, 5, 6, 7), as well as at least six shifting elements (03, 04, 14, 17, 36, 56), including brakes and clutches, whose selective engagement brings about different gear ratios between the drive shaft (1) and the output shaft (2), so that seven forward gears and one reverse gear can be realized, a drive takes place through a first shaft (1), which is continuously connected with a sun wheel of the first planetary gears (P1), output takes place through a second shaft (2), which is continuously in connection with an annulus of the second planetary gear set (P2) and an element of the third planetary gears (P3), a third shaft (3) is continuously connected with an annulus of the first planetary gears (P1), a fourth shaft (4) is continuously connected with a rod of the second planetary gears (P2) and a further element of the third planetary gears (P3), a fifth shaft (5) is continuously connected with a further element of the first planetary gear set (P1), a sixth shaft (6) is continuously connected with a sun wheel of the second planetary gears (P2), a seventh shaft (7) is continuously connected with a sun wheel of the third planetary gears (P3), whereby the third shaft (3) can be coupled to the housing (G) through a first brake (03), the fourth shaft (4) can be coupled to the housing (G) through a second brake (04), a first clutch (14) detachably connects the first shaft (1) and the fourth shaft (4) with each other, a second clutch (17) detachably connects the first shaft (1) and the seventh shaft (7) with each other, a third clutch (36) detachably connects the third shaft (3) and the sixth shaft (6) with each other, and whereby a fourth clutch (56) detachably connects the fifth shaft (5) and the sixth shaft (6) with each other.