Device for driving at least one wheel of an aircraft landing gear

Patent metadata

Field	Value
Publication number	US-12397906-B2
Application number	US-202318467019-A
Country	US
Kind code	B2
Filing date	Sep 14, 2023
Priority date	Sep 16, 2022
Publication date	Aug 26, 2025
Grant date	Aug 26, 2025

Abstract

A device for driving at least one wheel of an aircraft landing gear is provided. The device includes at least one wheel having a rim, an electric motor having a shaft, and a mechanical transmission system for mechanical transmission between the shaft of the motor and the rim. The mechanical transmission system includes a mechanical reduction gear. The mechanical reduction gear includes a sun gear secured in rotation to the shaft and having an external toothing, a stationary ring gear with internal toothing, a movable ring gear secured in rotation to the rim and having an internal toothing, and planet gears that are meshed with the sun gear and each have two external toothing meshed respectively with the toothing of the stationary and movable ring gears.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A device for driving at least one wheel of an aircraft landing gear, the device comprising:
at least one landing gear wheel including a rim having an axis of rotation;
an electric motor including a shaft; and
a mechanical transmission system for mechanical transmission between the shaft of the motor and the rim, the mechanical transmission system including a mechanical reduction gear, the mechanical reduction gear comprising:
a sun gear secured in rotation to the shaft of the motor, the sun gear being centered on the axis of rotation and having an external toothing;
a stationary ring gear centered on the axis of rotation and having an internal toothing, the stationary ring gear being configured to be secured to a stator of the device;
a movable ring gear centered on the axis of rotation and having an internal toothing, the movable ring gear being secured in rotation to the rim; and
planet gears which are meshed with the sun gear, the planet gears being carried by a planet carrier which is mobile in rotation about the axis of rotation, each of the planet gears having two external toothings meshed respectively with the toothing of the stationary and movable ring gears,
wherein the toothing of the stationary and movable ring gears have the same diameter.

2. The device of claim 1 , wherein the planet gears are each centered and guided by:
two roller bearings carried by the planet carrier, wherein the toothing of each of the planet gears is located between these roller bearings; or
two needle bearings carried by the planet carrier, wherein each of the needle bearings is radially aligned with one of the toothing of the planet gear.

3. The device of claim 1 , wherein the toothing of the stationary and movable ring gears have different numbers of teeth.

4. The device of claim 1 , wherein all the toothings are selected from straight, helical, or herringbone toothings.

5. The device of claim 1 , wherein the motor has an annular shape centered on the axis of rotation and arranged next to the reduction gear.

6. The device claim 1 , wherein the motor is arranged aside the planet gears along the axis of rotation.

7. The device of claim 1 , wherein:
the two external toothings of each of the planet gears comprise a first external toothing having a smallest diameter and a second external toothing having a greatest diameter which is different from the smallest diameter;
the first external toothing having the smallest diameter meshing with the toothing of the stationary ring gear; and
the second external toothing having the greatest diameter meshing with the toothing of the movable ring gear.

8. The device of claim 1 , wherein the electric motor is arranged on the side of the stationary ring gear and on the opposite side to the movable ring gear.

9. The device of claim 1 , wherein the planet carrier is arranged on the side of the electric motor.

10. The device of claim 1 , wherein each of the planet gears is meshed by a first toothing with the toothing of the sun gear and the toothing of the stationary ring gear, and by a second toothing with the toothing of the movable ring gear.

11. The device of claim 1 , wherein each of the planet gears is meshed by a first toothing with the toothing of the sun gear and the toothing of the movable ring gear, and by a second toothing with the toothing of the stationary ring gear.

12. The device of claim 1 , wherein the planet gears are arranged around at least part of the shaft of the motor.

Assignees

• Safran Trans Systems

Inventors

• Fernandez Maxime
• Douy Yohan
• Francois Loïc
• Morelli Boris Pierre Marcel
• Peltier Jordane Emile André

Classifications

• F16H2057/085

  Bearings for orbital gears · CPC title

• F16H2001/2881

  comprising two axially spaced central gears, i.e. ring or sun gear, engaged by at least one common orbital gear wherein one of the central gears is forming the output · CPC title

• F16H1/28

  with gears having orbital motion · CPC title

• Y02T50/80

  Energy efficient operational measures, e.g. ground operations or mission management · CPC title

• F16H1/2809

  with means for equalising the distribution of load on the planet gears · CPC title