Aircraft turbomachine with mechanical reducer and contrarotative turbine

Patent metadata

Field	Value
Publication number	US-11415045-B2
Application number	US-201916597505-A
Country	US
Kind code	B2
Filing date	Oct 9, 2019
Priority date	Oct 10, 2018
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

Aircraft turbomachine with mechanical reducer and counter-rotating turbine are described. The turbomachine includes a fan driven in rotation by a fan shaft, a mechanical reducer with epicyclic gear train, a gas generator comprising a counter-rotating turbine, a first turbine shaft of which is coupled to an input shaft of the reducer and to a pin, and a second turbine shaft of which is coupled to the fan shaft. The guidance of the reducer input shaft is provided by a first ball bearing, the guidance of the pin is provided by a second roller bearing, and the guidance of the first shaft is provided by a third roller bearing axially interposed between the first and second bearings.

First claim

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

1. An aircraft turbomachine with a mechanical reducer and a counter-rotating turbine, comprising:
a fan driven in rotation by a fan shaft;
the mechanical reducer with an epicyclic gear train;
a gas generator including the counter-rotating turbine, a first turbine shaft coupled to an input shaft of the reducer and to a pin of a low-pressure compressor of the gas generator, and a second turbine shaft coupled to the fan shaft and to an output shaft of the reducer;
a first ball bearing located downstream of the reducer between the input shaft and an input casing, the first ball bearing guiding the input shaft of the reducer;
a second roller bearing mounted between the pin and an intermediate casing of the turbomachine, the second roller bearing guiding the pin; and
a third roller bearing axially interposed between the first and second bearings and radially located at an intermediate position between the first shaft and the input shaft, the third roller bearing guiding the first shaft.

2. The turbomachine according to claim 1 , further comprising
an upstream roller bearing and a downstream ball bearing, the upstream roller bearing and downstream ball bearing located upstream of the reducer, between the fan and output shafts and the input casing, the upstream roller bearing and downstream ball bearing guiding the fan shaft and the output shaft.

3. The turbomachine according to claim 1 , wherein the first bearing has an average diameter greater than the average diameter of the second bearing, which is itself greater than the average diameter of the third bearing.

4. The turbomachine according to claim 1 , wherein the pin is engaged on the first shaft and axially fixed thereto by a first nut screwed on the first shaft.

5. The turbomachine according to claim 4 , wherein the fan shaft and the output shaft are axially fixed on the second shaft by a second nut screwed on the second shaft.

6. The turbomachine according to claim 1 , wherein the first shaft is connected at a downstream end to a first rotor of the counter-rotating turbine, and the second shaft is connected at a downstream end to a second rotor of the counter-rotating turbine, the first turbine rotor comprising wheels interposed between wheels of the second turbine rotor.

7. The turbomachine according to claim 6 , wherein the first and second turbine rotors are surrounded by a casing; and
a downstream end of the casing includes a flange for fixing to an exhaust casing of the turbomachine.

8. The turbomachine according to claim 1 , wherein the first turbine shaft is coupled to an input shaft of the reducer such that the first shaft is integral in rotation with the input shaft.

9. An aircraft turbomachine with a mechanical reducer and a counter-rotating turbine, comprising:
a fan driven in rotation by a fan shaft;
the mechanical reducer with an epicyclic gear train;
a gas generator including the counter-rotating turbine, a first turbine shaft coupled to an input shaft of the reducer and to a pin of a low-pressure compressor of the gas generator, and a second turbine shaft coupled to the fan shaft and to an output shaft of the reducer;
a first ball bearing located downstream of the reducer between the input shaft and an input casing, the first ball bearing guiding the input shaft of the reducer;
a second roller bearing mounted between the pin and an intermediate casing of the turbomachine, the second roller bearing guiding the pin; and
a third roller bearing axially interposed between the first and second bearings and radially located at an intermediate position between the first shaft and the input shaft, the third roller bearing being mounted between the second shaft and the first shaft.

10. An aircraft turbomachine with a mechanical reducer and a counter-rotating turbine, comprising:
a fan driven in rotation by a fan shaft;
the mechanical reducer with an epicyclic gear train;
a gas generator including the counter-rotating turbine, a first turbine shaft coupled to an input shaft of the reducer and to a pin of a low-pressure compressor of the gas generator, and a second turbine shaft coupled to the fan shaft and to an output shaft of the reducer;
a first ball bearing located downstream of the reducer between the input shaft and an input casing, the first ball bearing guiding the input shaft of the reducer;
a second roller bearing mounted between the pin and an intermediate casing of the turbomachine, the second roller bearing guiding the pin; and
a third roller bearing axially interposed between the first and second bearings and radially located at an intermediate position between the first shaft and the input shaft, the third roller bearing being located in between the second shaft and the input shaft.

Assignees

• Safran Aircraft Engines

Inventors

• Levisse Paul Ghislain Albert
• Belmonte Olivier
• Formica Olivier

Classifications

• F02C3/067 Primary

  having counter-rotating rotors (F02C3/073 takes precedence) · CPC title

• F02K3/06

  with front fan · CPC title

• F05D2260/40311

  of the epicyclical, planetary or differential type · CPC title

• F02C7/36

  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

• F02C7/06

  Arrangements of bearings (bearings F16C); Lubricating ({of turbo machines F01D25/18; of machines or} engines in general F01M) · CPC title