Multi-speed transmission with integrated electric motor
View Patent ↗An automatic transmission includes an input shaft or member, an output shaft or member and three simple and one compound planetary gear assemblies each including a sun gear, a planet gear carrier with a plurality of planet gears and a ring gear. The input shaft or member is coupled to the sun gear of the second planetary gear assembly and the output shaft is coupled to the planet gear carrier of the fourth planetary gear assembly. An electric motor is coupled to and drives the sun gear of the fourth planetary gear assembly. The transmission also includes six torque transmitting devices: four friction brakes and two friction clutches.
1. A multiple speed automatic transmission comprising, in combination,
a first, a second, a third and a fourth planetary gear assembly, each of said planetary gear assemblies having three components,
an input member connected to a first component of said second planetary gear assembly,
an output member connected to a first component of said fourth planetary gear assembly,
a first component of said first planetary gear assembly coupled to a second component of said second planetary gear assembly,
a second component of said first planetary gear assembly coupled to a third component of said second planetary gear assembly,
said third component of said second planetary gear assembly coupled to a first component of said third planetary gear assembly,
a second component of said third planetary gear assembly coupled to a second component of said fourth planetary gear assembly,
a third component of said third planetary gear assembly coupled to said first component of said fourth planetary gear assembly,
a electric motor having an output connected to a third component of said fourth planetary gear assembly, and
a plurality of torque transmitting devices selectively engageable to connect: a third component of said first planetary gear assembly to ground, said first component of said first planetary gear assembly and said second component of said second planetary gear assembly to ground, said second component of said first planetary gear assembly to ground, said second component of said third planetary gear assembly and said second component of said fourth planetary gear assembly to ground, said input member to said second component of said third planetary gear assembly and said input member to said third component of said fourth planetary gear assembly.
2. The multiple speed automatic transmission of claim 1 wherein each of said three components of said first, second, third and fourth planetary gear assemblies is one of a sun gear, a ring gear and a planet gear carrier.
3. The multiple speed automatic transmission of claim 1 wherein said first component of said first planetary gear assembly is a ring gear, said second component of said first planetary gear assembly is a planet gear carrier and said third component of said first planetary gear assembly is a sun gear.
4. The multiple speed automatic transmission of claim 1 wherein said second planetary gear assembly is a compound planetary gear assembly and said first component of said second planetary gear assembly is a sun gear, said second component of said second planetary gear assembly is a ring gear and said third component of said second planetary gear assembly is a planet gear carrier.
5. The multiple speed automatic transmission of claim 1 wherein said first component of said third planetary gear assembly is a sun gear, said second component of said third planetary gear assembly is a planet gear carrier and said third component of said third planetary gear assembly is a ring gear.
6. The multiple speed automatic transmission of claim 1 wherein said first component of said fourth planetary gear assembly is a planet gear carrier, said second component of said fourth planetary gear assembly is a ring gear and said third component of said fourth planetary gear assembly is a sun gear.
7. A multiple speed automatic transmission comprising, in combination,
a first, a second, a third and a fourth planetary gear assembly, each of said planetary gear assemblies having a first component, a second component and a third component,
an input member connected to said first component of said second planetary gear assembly,
an output member connected to said first component of said fourth planetary gear assembly,
a first member for connecting said first component of said first planetary gear assembly with said second component of said second planetary gear assembly,
a second member for connecting said second component of said first planetary gear assembly with said third component of said second planetary gear assembly,
a third member for connecting said third component of said second planetary gear assembly with said first component of said third planetary gear assembly,
a fourth member for connecting said second component of said third planetary gear assembly with said second component of said fourth planetary gear assembly,
a fifth member for connecting said third component of said third planetary gear assembly with said first component of said fourth planetary gear assembly,
a electric motor having an output connected to said third component of said fourth planetary gear assembly, and
a plurality of torque transmitting devices selectively engageable to connect: said third component of said first planetary gear assembly to ground, said first connecting member to ground, said second component of said first planetary gear assembly to ground, said fourth connecting member to ground, said input member to said third component of said fourth planetary gear assembly and said input member to said second component of said third planetary gear assembly.
8. The multiple speed automatic transmission of claim 7 wherein a first group of said plurality of torque transmitting devices are brakes and a second group of said plurality of torque transmitting devices are clutches.
9. The multiple speed automatic transmission of claim 7 wherein each of said first, second and third components of said first, second, third and fourth planetary gear assemblies is one of a sun gear, a ring gear and a planet gear carrier.
10. The multiple speed automatic transmission of claim 7 wherein said first component of said first planetary gear assembly is a ring gear, said second component of said first planetary gear assembly is a planet gear carrier and said third component of said first planetary gear assembly is a sun gear.
11. The multiple speed automatic transmission of claim 7 wherein said first component of said second planetary gear assembly is a sun gear, said second component of said second planetary gear assembly is a ring gear and said third component of said second planetary gear assembly is a planet gear carrier.
12. The multiple speed automatic transmission of claim 7 wherein said first component of said third planetary gear assembly is a sun gear, said second component of said third planetary gear assembly is a planet gear carrier and said third component of said third planetary gear assembly is a ring gear.
13. The multiple speed automatic transmission of claim 7 wherein said first component of said fourth planetary gear assembly is a planet gear carrier, said second component of said fourth planetary gear assembly is a ring gear and said third component of said fourth planetary gear assembly is a sun gear.
14. The multiple speed automatic transmission of claim 7 wherein said second planetary gear assembly is a compound planetary gear assembly.
15. A multiple speed automatic transmission comprising, in combination,
an input member,
an output member,
a first planetary gear assembly having a sun gear, a planet gear carrier rotatably supporting a plurality of planet gears and a ring gear,
a second planetary gear assembly having a sun gear coupled to and driven by said input member, a planet gear carrier coupled to said planet gear carrier of said first planetary gear assembly and rotatably supporting a plurality of planet gears and a ring gear coupled to said ring gear of said first planetary gear assembly,
a third planetary gear assembly having a sun gear coupled to said planetary gear carrier of said second planetary gear assembly, a planet gear carrier rotatably supporting a plurality of planet gears and a ring gear,
a fourth planetary gear assembly having a sun gear, a planet gear carrier coupled to and driving said output member, coupled to said ring gear of said third planetary gear assembly and rotatably supporting a plurality of planet gears and a ring gear coupled to said planet gear carrier of said third planetary gear assembly, and
an electric motor having an output member coupled to said sun gear of said fourth planetary gear assembly.
16. The multiple speed automatic transmission of claim 15 further including a first friction brake disposed between said sun gear of said first planetary gear assembly and a housing, a second friction brake disposed between said ring gears of said first and said second planetary gear assemblies and said housing, a third friction brake disposed between said planet gear carrier of said first planetary gear assembly and said housing, and a fourth friction brake disposed between said planet gear carrier of said third planetary gear assembly and said ring gear of said fourth planetary gear assembly and said housing.
17. The multiple speed automatic transmission of claim 15 further including a first friction clutch disposed between said input member and said sun gear of said fourth planetary gear assembly and a second friction clutch disposed between said input member and said planet gear carrier of said third planetary gear assembly.
18. The multiple speed automatic transmission of claim 15 wherein said first, third and fourth planetary gear assemblies are simple planetary gear assemblies and said second planetary gear assembly is a compound planetary gear assembly.
19. The multiple speed automatic transmission of claim 15 wherein said electric motor may also function as a generator.