Six-speed powertrain of an automatic transmission

Abstract

A six-speed powertrain of an automatic transmission includes a first single pinion planetary gear set having a first sun gear, two a first planet carriers carrier, a first planetary gear, and a first ring gear. A second single pinion planetary gear set has a second sun gear, a second planetary gear, and a second ring gear. A double pinion planetary gear set has a third sun gear, a pair of third planetary gears, and a third ring gear. One planetary gear of the pair of third planetary gears and the second planetary gear are commonly connected by a common planet carrier such that the second and third planetary gears may independently rotate.

1. A six-speed powertrain of an automatic transmission comprising first, second, and third planetary gear sets, an input shaft, and a transmission case, wherein:
 the first planetary gear set is a first single pinion planetary gear set, the second planetary gear set is a second single pinion planetary gear set, and the third planetary gear set is a double pinion planetary gear set;  
 the first single pinion planetary gear set has a first sun gear, two  a first planet carriers  carrier, a first planetary gear, and a first ring gear;  
 the second single pinion planetary gear set has a second sun gear, a second planetary gear, and a second ring gear;  
 the double pinion planetary gear set is disposed adjacent to the second single pinion planetary gear set and has a third sun gear, a pair of third planetary gears, and a third ring gear;  
 one planetary gear of the pair of third planetary gears and the second planetary gear are commonly connected by a common planet carrier such that the second and third planetary gears may independently rotate;  
 the third ring gear and the first ring gear are fixedly connected such that they are integrally formed;  
 the second ring gear and one  the first planet carrier are fixedly connected; and  
 a torque of the input shaft is always transmitted to the second sun gear or the third sun gear.  
 
     
     
       2. The powertrain of  claim 1 , wherein:
 the first sun gear is variably connected with the input shaft via a clutch;  
 the one  first planet carrier and the second ring gear are variably connected with the input shaft via a clutch;  
 the other  first planet carrier is variably connected with the transmission case via a brake and a one-way clutch disposed in parallel;  
 the third sun gear is variably connected with the transmission case via a brake;  
 the first sun gear is variably connected with the transmission case via a brake;  
 the second sun gear is fixedly connected with the input shaft; and  
 the third ring gear is fixedly connected with the first ring gear and they act as output elements.  
 
     
     
       3. The powertrain of  claim 2 , wherein an output gear is connected to the third ring gear acting as an output element. 
     
     
       4. The powertrain of  claim 2 , wherein an output gear is connected to the first ring gear acting as an output element. 
     
     
       5. The powertrain of  claim 1 , wherein the first sun gear is variably connected with the input shaft via a clutch;
 a second planet carrier is additionally included in the second single pinion planetary gear set and is variably connected with the input shaft via a clutch;  
 the other  first planet carrier is variably connected with the transmission case via a brake and a one way  one- way  clutch disposed in parallel;  
 the third sun gear is variably connected with the transmission case via a brake;  
 the first sun gear is variably connected with the transmission case via a brake;  
 the second sun gear is fixedly connected with the input shaft; and  
 the third ring gear is fixedly connected with the first ring gear and they act as output elements.  
 
     
     
       6. The powertrain of  claim 5 , wherein the third ring gear acting as an output element is connected with an output gear. 
     
     
       7. The powertrain of  claim 5 , wherein the first ring gear acting as an output element is connected with an output gear. 
     
     
       8. The powertrain of  claim 1 , wherein:
 the first sun gear is variably connected with the input shaft via a clutch;  
 the common planet carrier commonly connecting the second single pinion planatery  planetary gear set and the double pinion planetary gear set is variably connected with the input shaft via a clutch;  
 the other  first planet carrier is variably connected with the transmission case via a brake and a one-way clutch disposed in parallel;  
 the third sun gear is variably connected with the transmission case via a brake;  
 the first sun gear is variably connected with the transmission case via a brake;  
 the second sun gear is fixedly connected with the input shaft; and  
 the third ring gear is fixedly connected with the first ring gear and they act as output elements.  
 
     
     
       9. The powertrain of  claim 8 , wherein the third ring gear is connected with an output gear and acts as an output element. 
     
     
       10. The powertrain of  claim 8 , wherein the first ring gear is connected with an output gear and acts as an output element. 
     
     
       11. The powertrain of  claim 1 , wherein:
 the second sun gear is variably connected with the input shaft via a clutch;  
 a third planet carrier is additionally included in the double pinion planetary gear set and is variably connected with the input shaft via a clutch;  
 the third planet carrier is variably connected with the transmission case via a brake and an  a one-way clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a brake;  
 the second sun gear is variably connected with the transmission case via a brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       12. The powertrain of  claim 1 , wherein:
 the second sun gear is variably connected with the input shaft via a clutch;  
 the common planet carrier is variably connected with the input shaft via a clutch;  
 a third planet carrier is additionally included in the double pinion planetary gear set and is variably connected with the transmission case via a brake and an one way  a one- way  clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a brake;  
 the second sun gear is variably connected with the transmission case via a brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       13. The powertrain of  claim 1 , wherein:
 the second sun gear is variably connected with the input shaft via a clutch;  
 a third planet carrier is additionally included in the double pinion planetary gear set and is variably connected with the input shaft via a clutch;  
 a second planet carrier is additionally included in the second single pinion planetary gear set, separately formed from the second planetary gear,  and is variably connected with the transmission case via a brake and an one way  a one- way  clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a brake;  
 the second sun gear is variably connected with the transmission case via a brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       14. The powertrain of  claim 1 , wherein:
 the second sun gear is variably connected with the input shaft via a clutch;  
 the third ring gear is variably connected with the input shaft via a clutch;  
 a second planet carrier is additionally included in the second single pinion planetary gear set, separately formed from the second planetary gear,  and is variably connected with the transmission case via a brake and an one way  a one- way  clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a brake;  
 the second sun gear is variably connected with the transmission case via a brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       15. The powertrain of any one of  claim 11  to  claim 14 , wherein the first planet carrier acting as an output element is connected with an output gear. 
     
     
       16. A six-speed powertrain of an automatic transmission comprising first, second, and third planetary gear sets, an input shaft, and a transmission case, wherein:
 the first planetary gear set is a first single pinion planetary gear set, the second planetary gear set is a second single pinion planetary gear set, and the third planetary gear set is a double pinion planetary gear set;  
 the first single pinion planetary gear set has a first sun gear, two  a first planet carriers  carrier, a first planetary gear, and a first ring gear;  
 the second single pinion planetary gear set has a second sun gear, a second planetary gear, and a second ring gear;  
 the double pinion planetary gear set is disposed adjacent to the second planetary gear set and has a third sun gear, a pair of third planetary gears, and a third ring gear;  
 one planetary gear of the pair of third planetary gears and the second planetary gear are commonly connected by a common planet carrier such that the second and third planetary gears may independently rotate;  
 the third ring gear and the first ring gear are fixedly connected such that they are integrally formed;  
 the second ring gear and one  the first planet carrier are fixedly connected;  
 a torque of the input shaft is always transmitted to the third sun gear or the second sun gear; and  
 frictional elements consisting of two clutches and three brakes are operated to realize six forward speeds and one reverse speed.  
 
     
     
       17. The powertrain of  claim 16 , wherein:
 the first sun gear is variably connected with the input shaft via a first clutch;  
 the one  first planet carrier and the second ring gear are variably connected with the input shaft via a second clutch;  
 the other  first planet carrier is variably connected with the transmission case via a first brake and a one-way clutch disposed in parallel;  
 the third sun gear is variably connected with the transmission case via a second brake;  
 the first sun gear is variably connected with the transmission case via a third brake;  
 the second sun gear is fixedly connected with the input shaft; and  
 the third ring gear is fixedly connected with the first ring gear and they act as output elements.  
 
     
     
       18. The powertrain of  claim 17 , wherein the third ring gear is connected with an output gear and acts as an output element. 
     
     
       19. The powertrain of  claim 17 , wherein the first ring gear is connected with an output gear and acts as an output element. 
     
     
       20. The powertrain of  claim 16 , wherein:
 the first sun gear is variably connected with the input shaft via a first clutch;  
 a second planet carrier is additionally included in the second single pinion planetary gear set and is variably connected with the input shaft via a second clutch;  
 the other  first planet carrier is variably connected with the transmission case via a first brake and a one way  one- way  clutch disposed in parallel;  
 the third sun gear is variably connected with the transmission case via a second brake;  
 the first sun gear is variably connected with the transmission case via a third brake;  
 the second sun gear is fixedly connected with the input shaft; and  
 the third ring gear is fixedly connected with the first ring gear and they act as output elements.  
 
     
     
       21. The powertrain of  claim 20 , wherein:
 the third ring gear is connected with the output gear and acts as an output element.  
 
     
     
       22. The powertrain of  claim 20 , wherein:
 the first ring gear is connected with the output gear and acts as an output element.  
 
     
     
       23. The powertrain of  claim 16 , wherein the first sun gear is variably connected with the input shaft via a first clutch;
 the common planet carrier is variably connected with the input shaft via a second clutch;  
 the other  first planet carrier is variably connected with the transmission case via a first brake and a one-way clutch disposed in parallel;  
 the third sun gear is variably connected with the transmission case via a second brake;  
 the first sun gear is variably connected with the transmission case via a third brake;  
 the second sun gear is fixedly connected with the input shaft; and  
 the third ring gear is fixedly connected with the first ring gear and they act as output elements.  
 
     
     
       24. The powertrain of  claim 23 , wherein:
 the third ring gear is connected with the output gear and acts as an output element.  
 
     
     
       25. The powertrain of  claim 23 , wherein:
 the first ring gear is connected with the output gear and acts as an output element.  
 
     
     
       26. The powertrain of  claim 16 , wherein:
 the second sun gear is variably connected with the input shaft via a first clutch;  
 a third planet carrier is additionally included in the double pinion planetary gear set and is variably connected with the input shaft via a second clutch;  
 the third planet carrier is also variably connected with the transmission case via a first brake and an  a one-way clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a second brake;  
 the second sun gear is variably connected with the transmission case via a third brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       27. The powertrain of  claim 16 , wherein:
 the second sun gear is variably connected with the input shaft via a first clutch;  
 the common planet carrier being commonly connected with the second single pinion planetary gear set and the double pinion planetary gear set is variably connected with the input shaft via a second clutch;  
 a third planet carrier is additionally included in the double pinion planetary gear set and is variably connected with the transmission case via a first brake and an one way  a one- way  clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a second brake;  
 the second sun gear is variably connected with the transmission case via a third brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       28. The powertrain of  claim 16 , wherein:
 the second sun gear is variably connected with the input shaft via a first clutch;  
 a third planet carrier is additionally included in the double pinion planetary gear set and is variably connected with the input shaft via a second clutch;  
 a second planet carrier is additionally included in the second single pinion planetary gear set, separately formed from the second planetary gear,  and is variably connected with the transmission case via a first brake and an one way  a one- way  clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a second brake;  
 the second sun gear is variably connected with the transmission case via a third brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       29. The powertrain of  claim 16 , wherein:
 the second sun gear is variably connected with the input shaft via a first clutch;  
 the third ring gear is variably connected with the input shaft via a second clutch;  
 a second planet carrier is additionally included in the second single pinion planetary gear set, separately formed from the second planetary gear,  and is variably connected with the transmission case via a first brake and an one way  a one- way  clutch disposed in parallel;  
 the first sun gear is variably connected with the transmission case via a second brake;  
 the second sun gear is variably connected with the transmission case via a third brake;  
 the third sun gear is fixedly connected with the input shaft; and  
 the other  first planet carrier acts as an output element.  
 
     
     
       30. The powertrain of any one of  claim 26  to  claim 29 , wherein:
 the first planet carrier acting as an output element is connected with an output gear.  
 
     
     
       31. The powertrain of any one of  claim 17 ,  claim 20 ,  claim 23 , and  claim 26  to  claim 29 , wherein:
 the second brake and the one-way clutch are operated for a first forward speed;  
 the one-way clutch is released and the third brake is operated for a second forward speed from the first forward speed;  
 the third brake is released and the first clutch is operated for a third forward speed from the second forward speed;  
 the first clutch is released and the second clutch is operated for a fourth forward speed from the third forward speed;  
 the second brake is released and the first clutch is operated for a fifth forward speed from the fourth forward speed;  
 the first clutch is released and the third brake is operated for a sixth forward speed from the fifth forward speed; and  
 the first clutch and the first brake are operated for a reverse speed.  
 
     
     
       32. A powertrain of an automatic transmission comprising first, second, and third planetary gear sets, an input shaft, and a transmission case, wherein:
   the first planetary gear set is a first single pinion planetary gear set, the second planetary gear set is a second single pinion planetary gear set, and the third planetary gear set is a double pinion planetary gear set;        the first single pinion planetary gear set has a first sun gear, a first planet carrier, a first planetary gear, and a first ring gear;        the second single pinion planetary gear set has a second sun gear, a second planetary gear, and a second ring gear;        the double pinion planetary gear set is disposed adjacent to the second single pinion planetary gear set and has a third sun gear, a pair of third planetary gears, and a third ring gear;        one planetary gear of the pair of third planetary gears and the second planetary gear are commonly connected by a common planet carrier such that the second and third planetary gears may independently rotate;        the third ring gear and the first ring gear are fixedly connected such that they are integrally formed;        the second ring gear and the first planet carrier are fixedly connected; and        a torque of the input shaft is always transmitted to the second sun gear or the third sun gear.