Transmission for engine with two power inputs

Patent metadata

Field	Value
Publication number	US-11092082-B2
Application number	US-201816115790-A
Country	US
Kind code	B2
Filing date	Aug 29, 2018
Priority date	Aug 29, 2018
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

An engine includes first and second power inputs, and a power output. A transmission includes an epicyclic gear train engaged with the first power input and selectively engageable with the power output. The gear train has a sun gear centrally disposed and defining a center axis of the gear train, a ring gear, and planet gears mounted to a carrier. The planet gears are rotatable about respective planet gear axes. The planet gears are disposed in meshed engagement with the sun gear and the ring gear. A brake engageable in a first position with one of the sun gear, the carrier, and the ring gear slows a rotation thereof to transfer power from the first power input to the power output. The brake in a second position is disengageable from the sun gear, the carrier or the ring gear to decouple the first power input from the power output.

First claim

The invention claimed is:

1. A powerplant for a vehicle, comprising:
a first power input and a second power input, each associated with a different power source;
a power output; and
a transmission engaged with the first and second power inputs and with the power output, the transmission including
an epicyclic gear train engaged with the first power input and selectively engageable with the power output, the epicyclic gear train having a sun gear centrally disposed and defining a center axis of the epicyclic gear train, a ring gear, and planet gears mounted to a carrier, the planet gears rotatable about respective planet gear axes, the planet gears disposed in meshed engagement with the sun gear and the ring gear,
a brake engageable in a first position with one of the sun gear, the carrier, and the ring gear to slow a rotation thereof and transfer power from the first power input to the power output, the brake in a second position disengageable from said one of the sun gear, the carrier, and the ring gear to decouple the first power input from the power output such that no power is transmitted from the first power input to the power output,
a carrier shaft extending from the carrier and rotatable about the center axis, the carrier shaft engaging the power output to drive the power output, and
a first geared shaft disposed between the carrier shaft and the power output, the first geared shaft having a carrier gear member engaged with the carrier shaft and a first output gear member engaged with the power output.

2. The powerplant as defined in claim 1 , wherein the brake in the first position is engageable with the ring gear to slow the rotation of the ring gear about the center axis, and to thereby cause the planet gears to rotate within the ring gear and the carrier to rotate about the center axis, the carrier engaging the power output in the first position to drive the power output.

3. The powerplant as defined in claim 1 , wherein the brake in the second position is disengageable from the ring gear to allow rotation of the ring gear about the center axis, and to thereby cause each planet gear to rotate about its planet gear axis such that the carrier does not rotate about the center axis.

4. The powerplant as defined in claim 1 , wherein a diameter of the first output gear member is greater than a diameter of the carrier gear member.

5. The powerplant as defined in claim 1 , wherein the sun gear is engaged with the first power input to be driven thereby, the brake in the first position is engageable with the carrier to slow the rotation of the carrier about the center axis, and to thereby cause the ring gear to rotate about the center axis, the ring gear engaging the power output in the first position to drive the power output.

6. The powerplant as defined in claim 1 , wherein the ring gear is engaged with the first power input to be driven thereby, the brake in the first position is engageable with the sun gear to slow the rotation of the sun gear about the center axis, and to thereby cause the planet gears to rotate about the center axis to rotate the carrier, the carrier engaging the power output in the first position to drive the power output.

7. The powerplant as defined in claim 1 , wherein the carrier is engaged with the first power input to be driven thereby, the brake in the first position is engageable with the ring gear to slow the rotation of the ring gear about the center axis, and to thereby cause the sun gear to rotate about the center axis, the sun gear engaging the power output in the first position to drive the power output.

8. The powerplant as defined in claim 1 , further comprising a propeller or a rotor mounted to the power output, the propeller or the rotor drivable only by power provided by the power output.

9. A powerplant for a vehicle, comprising:
a first power input and a second power input, each associated with a different power source;
a power output; and
a transmission engaged with the first and second power inputs and with the power output, the transmission including
an epicyclic gear train engaged with the first power input and selectively engageable with the power output, the epicyclic gear train having a sun gear centrally disposed and defining a center axis of the epicyclic gear train, a ring gear, and planet gears mounted to a carrier, the planet gears rotatable about respective planet gear axes, the planet gears disposed in meshed engagement with the sun gear and the ring gear,
a brake engageable in a first position with one of the sun gear, the carrier, and the ring gear to slow a rotation thereof and transfer power from the first power input to the power output, the brake in a second position disengageable from said one of the sun gear, the carrier, and the ring gear to decouple the first power input from the power output such that no power is transmitted from the first power input to the power output, the second power input engageable with the power output upon the brake engaging in the first position, and
a second geared shaft disposed between the second power input and the power output, the second geared shaft having a second power input gear member engaged with the second power input and a second output gear member engaged with the power output.

10. The powerplant as defined in claim 9 , wherein a diameter of the second output gear member is less than a diameter of the second power input gear member.

11. A method of operating a powerplant having a first power input and a second power input to selectively provide power to a power output, the powerplant having an epicyclic transmission with a sun gear, planet gears mounted to a planet carrier, and a ring gear, the transmission engaged with the first and second power inputs and with the power output, the method comprising operating a brake of the transmission to:
engage one of the sun gear, the planet gears, and the ring gear of the transmission to slow a rotation thereof and transfer power from the first power input to the power output via a carrier shaft extending from the planet carrier and rotatable therewith, including using a first geared shaft disposed between the carrier shaft and the power output, the first geared shaft having a carrier gear member engaged with the carrier shaft and a first output gear member engaged with the power output; and
disengage from said one of the sun gear, the planet gears, and the ring gear to decouple the first power input from the power output such that no power is transmitted from the first power input to the power output.

12. The method as defined in claim 11 , wherein operating the brake to disengage from said one of the sun gear, the planet gears, and the ring gear includes disengaging the brake from the ring gear during start of the powerplant so as to start the powerplant without driving a propeller or a rotor.

13. The method as defined in claim 11 , wherein operating the brake to engage said one of the sun gear, the planet gears, and the ring gear includes simultaneously engaging the second power input with the power output.

14. The method as defined in claim 11 , wherein operating the brake to engage said one of the sun gear, the planet gears, and the ring gear includes allowing the planet gears to rotate about the center axis, a carrier mounted to the planet gears also rotating about the center axis.

15. The method as defined in claim 11 , wherein operating the brake to disengage from said one of the sun gear, the planet gears, and the ring gear includes allowing the ring gear to rotate about the center axis.

16. The method as defined in claim 15 , wher

Assignees

• Pratt & Whitney Canada

Inventors

• Brito Roberto
• Poulin Martin

Classifications

• F16H37/065

  with a plurality of driving or driven shafts (F16H37/0806 takes precedence) · CPC title

• F02C7/36 Primary

  Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user ({F02C3/107 - F02C3/13 and} F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H) · CPC title

• F02C6/206

  the vehicles being airscrew driven · CPC title

• F05D2220/50

  for auxiliary power units (APU's) · CPC title

• F16H3/44 Primary

  using gears having orbital motion · CPC title