Ball type CVT with output coupled powerpaths

• US 10,088,026 B2
• Filed: 02/02/2017
• Issued: 10/02/2018
• Est. Priority Date: 09/07/2012
• Status: Expired due to Fees

• Current Assignee: DANA Limited (Caterpillar Incorporated)
• Original Assignee: DANA Limited (Caterpillar Incorporated)
• Inventors: Versteyhe, Mark R. J., Byltiauw, Matthias W. J.
• Primary Examiner(s): Scott, Jacob S.
• Assistant Examiner(s): Dang, Tinh
• Application Number:
  US15/423,131
• Publication Number:
  US 20170184188A1
• Time in Patent Office: 607 Days
• CPC Class Codes: F16H 15/28 with external friction surface
• CPC Class Codes: F16H 15/52 in which a member of uniform effective diameter mounted on a shaft may co-operate with different parts of another member
• CPC Class Codes: F16H 2037/0873 with switching, e.g. to change ranges
• CPC Class Codes: F16H 2037/0893 characterised in the ratio of the continuously variable transmission is different from zero when the output shaft speed is zero
• CPC Class Codes: F16H 2200/2005 with one sets of orbital gears
• CPC Class Codes: F16H 2200/2038 with three engaging means
• CPC Class Codes: F16H 37/0853 CVT using friction between rotary members having a first member of uniform effective diameter cooperating with different parts of a second member
• CPC Class Codes: F16H 37/086 CVT using two coaxial friction members cooperating with at least one intermediate friction member

Abstract

Systems, devices, and methods are provided for the transmission of power in motor vehicles. Power can be transmitted in a smoother and more efficient manner, with smaller and even less mechanical components, by splitting torque into two or more torque paths. A power transmission apparatus comprises a power input shaft, a planetary gear set coupled to the power input shaft, and a variator, such as a continuously variable transmission (CVT), coupled to the gear set. The various components of the planetary gear set and the variator are arranged such that torque is split between two or more torque paths and then recombined before power is output to a gear box and a differential of the motor vehicle.

Claims

1. An apparatus for power transmission comprising:

a power input shaft;

a planetary gear set engaged with the power input shaft; and

a ball type variator including an input ring and an output ring engaged with the gear set,

wherein the apparatus is configured to split torque between a first torque path and a second torque path, wherein the ball-type variator comprises a plurality of balls in contact with the input ring and the output ring, each ball provided with a tiltable axis of rotation,

wherein a speed of the output ring is continuously variable corresponding to movement of the tiltable axis of rotation, wherein the planetary gear set comprises

a set of planet gears, a sun engaged with the set of planet gears and to the input ring of the variator, a carrier engaged with the power input shaft and with the set of planet gears, and a ring gear engaged with the set of planet gears and with the output ring of the variator, and

wherein the first torque path transmits rotational power passes from the power input shaft to the carrier of the planetary gear set, to the planet gears of the planetary gear set, to the sun gear of the planetary pear set, to the input ring of the variator, to the output ring of the variator, and then to the ring gear of the planetary gear set.

2. The power transmission apparatus of claim 1, wherein the second torque path passes from the power input shaft to the carrier of the planetary gear set, to the planet gears of the planetary gear set, and then to the ring gear of the planetary gear set.

3. The power transmission apparatus of claim 1, further comprising a gear box for transmitting an output power from the apparatus, the gear box being coupled to the planetary gear set.

4. The power transmission apparatus of claim 3, wherein the gear box is coupled to the ring gear of the planetary gear set.

5. The power transmission apparatus of claim 3, wherein the gear box is coupled to a differential.

6. The power transmission apparatus of claim 5, wherein the gear box comprises a three speed gear box.

7. The power transmission apparatus of claim 1 further comprising a traction fluid lubricant.

8. A vehicle comprising the power transmission apparatus of claim 1.

9. A method of transmitting power comprising:

driving an input shaft;

splitting torque from the input shaft between a first torque path and a second torque path; and

combining the first and second torque paths to form a single output,

wherein the first and second torque paths pass through a planetary gear set and the first torque path passes through a ball type variator coupled to the planetary gear set,

wherein the ball-type variator comprises a plurality of balls in contact with an input ring and an output ring, each ball provided with a tiltable axis of rotation, wherein a speed of the output ring is continuously variable corresponding to movement of the tiltable axis of rotation, and

wherein splitting torque further comprises transmitting rotational power through the first torque path, wherein the first torque path corresponds to power transmission from the power input shaft to a carrier of the planetary gear set, to a set of planet gears of the planetary gear set, to a sun gear of the planetary gear set, to an input ring of the variator, to the output ring of the variator, and then to a ring gear of the planetary gear set.

10. The power transmission method of claim 9, wherein splitting torque further comprises transmitting rotational power through the second torque path, wherein the second torque path corresponds to power transmission from the power input shaft to a carrier of the planetary gear set, to a set of planet gears of the planetary gear set, and then to a ring gear of the planetary gear set.

11. An apparatus for power transmission comprising:

a power input shaft;

a planetary gear set engaged with the power input shaft; and

a ball type variator including an input ring and an output ring engaged with the gear set, wherein the apparatus is configured to split torque between a first torque path and a second torque path,

wherein the ball-type variator comprises a plurality of balls in contact with the input ring and the output ring, each ball provided with a tiltable axis of rotation,

wherein a speed of the output ring is continuously variable corresponding to movement of the tiltable axis of rotation,

wherein the planetary gear set comprises a set of planet gears, a sun engaged with the set of planet gears and to the input ring of the variator, a carrier engaged with the power input shaft and with the set of planet gears, and

a ring gear engaged with the set of planet gears and with the output ring of the variator, and

wherein the second torque path passes from the power input shaft to the carrier of the planetary gear set, to the planet gears of the planetary gear set, and then to the ring gear of the planetary gear set.