Speed changing gear device having two independent gear assemblies

A speed changing gear device for an automatic transmission having an input member and an output member, comprising:

• a main gear assembly between said input member and said output member, for providing a plurality of operating positions, including at least four forward-drive positions and one reverse position, said main gear assembly including single-pinion type first planetary gear unit having a first sun gear, a first planetary pinion meshing with the first sun gear, a first ring gear meshing with the first planetary pinion, an a first carrier rotatably supporting the first planetary pinion, and a single-pinion type second planetary gear unit having a second sun gear, a second planetary pinion meshing with the second sun gear, a second ring gear meshing with the second planetary pinion, and a second carrier rotatably supporting the second planetary pinion;
• and
• an auxiliary gear assembly between said input member and said output member, for providing a direct drive position having a speed reduction ratio of 1, and a speed changing drive position having a speed reduction ratio of other than 1, said auxiliary gear assembly including a third planetary gear unit having a third sun gear, at least one third planetary pinion meshing with said third sun gear, a third ring gear meshing with said at least one third planetary pinion, and a third carrier rotatably supporting said at least one third planetary pinion;
• said main gear assembly further including:
• (a) one of (i) fixing means for fixing said first carrier and said second ring gear to each other, and (ii) first clutch means for connecting said first carrier and second ring gear to each other;
• (b) second clutch means for connecting said first sun gear and said second sun gear to each other;
• (c) third clutch means for connecting said first sun gear and said second carrier to each other;
• (d) fourth clutch means, distinct and separate from said first, second and third clutch means, for connecting said first ring gear and said input member to each other, said fourth clutch means being connected directly to said first ring gear and said input member;
• (e) fifth clutch means for connecting said first sun gear and said input member to each other;
• (f) first brake means for inhibiting said second sun gear from rotating;
• and
• (g) second brake means for inhibiting said second carrier from rotating;
• said first planetary gear unit being positioned on a side of the main gear assembly closest to the input member, and said second planetary gear unit being positioned on a side of the main gear assembly closest to the output member, and said first and second planetary gear units being arranged in an axial direction of said main gear assembly.