Ball type continuously variable transmission
View Patent ↗A variable transmission includes an input shaft, a planetary gear set drivingly engaged with a variator comprising, a variator carrier assembly, a first ring assembly, and a second ring assembly; and the output shaft, arranged to produce transmissions with continuously variable or infinitely variable output ratios.
1. A variable transmission comprising:
an input shaft;
a gear ratio comprising a first gear coupled to the input shaft, a countershaft and a second gear coupled to the countershaft;
a variator (CVP) comprising a first ring assembly coupled to the second gear on the countershaft, a carrier assembly comprising a plurality of tiltable variator balls, each ball drivingly engaged with the first ring assembly, and a second ring assembly drivingly engaged with the tiltable variator balls; and
a planetary gearset comprising a planet carrier drivingly engaged with the input shaft, a ring gear drivingly engaged with the second ring assembly of the variator, and a sun gear drivingly engaged with an output;
wherein the planetary gearset is configured to split power of the input shaft between the variator and a mechanical path going directly to the output.
2. The variable transmission of claim 1 , wherein the first ring assembly and the second ring assembly are drivingly coupled over a continuous range of speed ratios from a minimum speed ratio to a maximum speed ratio, and wherein the speed ratio is controlled by the tiltable variator balls.
3. The variable transmission of claim 1 , wherein the tiltable variator balls controls a first speed ratio between the first ring assembly and second ring assembly of the variator, and thereby controls a second speed ratio between the planet carrier and ring gear of the planetary gearset.
4. The variable transmission of claim 1 , wherein a minimum speed ratio and a maximum speed ratio between the input shaft and the sun gear of the planetary gearset span a range from negative to positive.
5. The variable transmission of claim 1 , further comprising a damper coupled to the input shaft and disposed between a power source and the variable transmission.
6. The variable transmission of claim 5 , further comprising a clutch disposed between the power source and the variable transmission.
7. The variable transmission of claim 6 , wherein the clutch is coupled to the damper or at a location to allow interrupting power transmission.
8. The variable transmission of claim 1 , wherein the variator comprises a traction fluid.
9. The variable transmission of claim 1 , wherein the gear ratio is configured to operate with reverse speeds.
10. The variable transmission of claim 1 , wherein the gear ratio decreases torque on the variator.
11. The variable transmission of claim 1 , wherein the gear ratio provides a first speed ratio between a power source and the first ring assembly without changing the rotation direction between the power source and the first ring assembly.
12. The variable transmission of claim 1 , wherein when the gear ratio is greater than 1 to the input of the variator, the minimum and maximum speeds of the planetary gearset are increased.
13. The variable transmission of claim 1 , wherein when the gear ratio is less than 1 to the input of the variator, the minimum and maximum speeds of the planetary gearset are decreased.
14. A vehicle driveline comprising: a power source, a variable transmission of claim 1 drivingly engaged with the power source, and a vehicle output drivingly engaged with the variable transmission.
15. A method comprising providing a vehicle driveline of claim 14 .