Method of engaging two gear elements, and a drive device implementing such a method

Patent metadata

Field	Value
Publication number	US-11428316-B2
Application number	US-201916366485-A
Country	US
Kind code	B2
Filing date	Mar 27, 2019
Priority date	Mar 28, 2018
Publication date	Aug 30, 2022
Grant date	Aug 30, 2022

Abstract

The invention provides an engagement method for engaging a first gear element with a second gear element, at least the second gear element being mounted to move between a meshing position and a disengaged position by means of an actuator. The engagement method including a step of driving at least one of the gear elements in rotation so as to establish a non-zero difference in speed of rotation between said gear elements, and a step of controlling the actuator to perform the following in succession:moving at least the second gear element towards the meshing position;on detecting contact between the gear elements, stopping the movement of the second gear element; andon detecting an ideal angular position for engaging said gear elements, moving the second gear element as quickly as possible into the meshing position.

First claim

The invention claimed is:

1. An engagement method for engaging a first gear element with a second gear element, at least the second gear element being mounted to move between a meshing position and a disengaged position by means of an actuator, the engagement method including a step of driving at least one of the gear elements in rotation so as to establish a non-zero difference in speed of rotation between said gear elements, and a step of controlling the actuator to perform the following in succession:
moving at least the second gear element towards the meshing position;
at the moment contact is detected between the gear elements, stopping the movement of the second gear element towards the meshing position; and
when a relative angular position of the gear elements allowing the engagement of said gear elements is detected, moving the second gear element into the meshing position as quickly as the actuator is capable of going.

2. The engagement method according to claim 1 , wherein the actuator comprises a cylinder within which a rod can move along an axis, a free end of the rod being connected to the second gear element and an end of the rod forming a piston cooperating with the cylinder to define a chamber connected to a source of pressurized fluid via a servo valve serving to control the pressure inside the chamber, and wherein:
the step of moving the second gear element towards the meshing position is carried out by increasing the pressure inside the chamber via the servo valve to reach a predetermined pressure so as to move the rod of the actuator towards the meshing position;
the step of detecting contact between the gear elements is carried out by detecting an increase of the pressure inside the chamber up to a first threshold;
the step of stopping the movement of the second gear element towards the meshing position is carried out by controlling the pressure inside the chamber via the servo valve so as to stop the rod advancing towards the meshing position;
the step of detecting a relative angular position of the gear elements allowing the engagement of said gear elements is carried out by detecting a decrease of the pressure inside the chamber down to a second threshold for a predefined duration;
the step of moving the second gear element into the meshing position as quickly as the actuator is capable of going is carried out by increasing the pressure inside the chamber via the servo valve as quickly as said servo valve is capable of going to bring the rod into the meshing position.

3. The engagement method according to claim 2 , wherein the first pressure threshold is substantially equal to 30 bars.

4. The engagement method according to claim 2 , wherein the second pressure threshold is substantially equal to 20 bars.

5. The engagement method according to claim 2 , wherein the predefined duration is substantially equal to 100 ms.

6. A drive device comprising a first gear element ( 1 ), a second gear element ( 2 ) movable by means of an actuator (V) between a meshing position with the first gear element and a disengaged position, a motor driving one of the gear elements in rotation, detector means (Cp) for detecting contact between said gear elements, and an electronic control unit (UC) connected to the actuator (V), to the motor, and to the detection means (Cp), the drive device being characterized in that the electronic control unit (UC) is arranged to perform the method according to claim 5 .

7. A drive device according to claim 6 , wherein the actuator comprises an actuator (V) having a rod (T) connected to the second gear element, a servovalve (Sv) controls the actuator (V), and the detector means comprise a pressure sensor (Cp).

8. A drive device according to claim 7 , wherein the actuator (V) is a hydraulic actuator.

9. A drive device according to claim 7 , wherein the motor is an electric motor.

10. An undercarriage fitted with a drive device according to claim 7 .

11. A drive device according to claim 6 , wherein the first gear element ( 1 ) is a toothed ring and the second gear element ( 2 ) is a roller pinion.

12. A drive device according to claim 11 , wherein the toothed ring ( 1 ) is secured to a wheel (R).

Assignees

• Safran Landing Systems

Inventors

• Fraim Julien
• Giraud Frédérik
• MARTIN FRéDéRIC
• Veillon Alexandre

Classifications

• B64C25/405

  Powered wheels, e.g. for taxing · CPC title

• Y02T50/80

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

• F16H3/34 Primary

  with gears shiftable otherwise than only axially · CPC title

• H02K7/116

  with gears · CPC title

• F16H2063/3093

  Final output elements, i.e. the final elements to establish gear ratio, e.g. coupling sleeves or other means establishing coupling to shaft · CPC title