JOURNAL BEARING FOR ROTATING GEAR CARRIER

• US 20160377166A1
• Filed: 04/19/2016
• Published: 12/29/2016
• Est. Priority Date: 06/23/2015
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Sheridan, William G.
• Granted Patent: US 10,443,708 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F01D 25/162 Bearing supports
• CPC Class Codes: F01D 25/166 Sliding contact bearing gas bearings F01D25/22
• CPC Class Codes: F02C 3/107 with two or more rotors connected by power transmission
• CPC Class Codes: F02C 7/36 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 Class Codes: F05D 2240/53 Hydrodynamic or hydrostatic bearings
• CPC Class Codes: F05D 2240/54 Radial bearings
• CPC Class Codes: F05D 2250/241 spherical
• CPC Class Codes: F05D 2260/40311 of the epicyclical, planetary or differential type
• CPC Class Codes: F05D 2260/98 Lubrication
• CPC Class Codes: F16H 1/28 with gears having orbital motion
• CPC Class Codes: F16H 2057/085 Bearings for orbital gears
• CPC Class Codes: F16H 57/043 within rotary parts, e.g. axial channels or radial openings in shafts
• CPC Class Codes: F16H 57/0471 Bearing
• CPC Class Codes: F16H 57/0479 Gears or bearings on planet carriers
• CPC Class Codes: F16H 57/0486 with fixed gear ratio differentials F16H57/0483
• CPC Class Codes: F16H 57/082 Planet carriers
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A gear system for a geared turbofan engine includes a sun gear, a planet gear supported in a carrier and engaged to the sun gear, a forward journal bearing and an aft journal bearing both supporting the planet gear. The carrier includes a forward wall supporting the forward journal bearing and an aft wall supporting the aft journal bearing. A ring gear is engaged to the planet gear. A geared turbofan engine is also disclosed.

Claims

1. A gear system for a geared turbofan engine comprising:

a sun gear;

a planet gear supported in a carrier and engaged to the sun gear;

a forward journal bearing and an aft journal bearing both supporting the planet gear, the carrier including a forward wall supporting the forward journal bearing and an aft wall supporting the aft journal bearing; and

a ring gear engaged to the planet gear.

2. The gear system as recited in claim 1, wherein one of the carrier and the ring gear is fixed.

3. The gear system as recited in claim 1, wherein the carrier is fixed and the ring gear rotates.

4. The gear system as recited in claim 1, wherein the aft journal bearing and the forward journal bearing have outer spherical surfaces.

5. The gear system as recited in claim 1, wherein each of the aft journal bearing and the forward journal bearing include an oil feed opening and an anti-rotation pin engaged to the corresponding one of the forward wall and aft wall of the carrier.

6. The gear system as recited in claim 5, wherein the carrier includes passages in communication with the oil feed opening for providing lubricant to each of the forward journal bearing and the aft journal bearing.

7. The gear system as recited in claim 1, wherein the planet gear includes an internal cavity.

8. The gear system as recited in claim 1, wherein the planet gear includes end sections on either side of a gear section including gear teeth, the end sections include a thickness less than two (2) times a height of gear teeth in the gear section.

9. The gear system as recited in claim 1, wherein the forward journal bearing and the aft journal bearing are made from at least one of a bronze material, a bronze coating, a bronze alloy and a copper-lead alloy.

10. A geared turbofan engine comprising:

a fan configured to drive air along a bypass flow path;

a compressor section configured to communicate compressed air to a combustor section for generating a high energy gas flow for driving a turbine section where energy is extracted and utilized to drive the compressor section and the fan section; and

a gear system driven by the turbine section, the gear system including a sun gear, a planet gear supported in a carrier and engaged to the sun gear;

a forward journal bearing and an aft journal bearing both supporting the planet gear, the carrier including a forward wall supporting the forward journal bearing and an aft wall supporting the aft journal bearing and a ring gear engaged to the planet gear.

11. The geared turbofan engine as recited in claim 10, wherein the carrier rotates and drives the fan and the ring gear is fixed.

12. The geared turbofan engine as recited in claim 10, wherein the carrier is fixed and the ring gear rotates to drive the fan.

13. The geared turbofan engine as recited in claim 10, wherein the aft journal bearing and the forward journal bearing have outer spherical surfaces.

14. The geared turbofan engine as recited in claim 10, wherein each of the aft journal bearing and the forward journal bearing include an oil feed opening and an anti-rotation pin engaged to the corresponding one of the forward wall and aft wall of the carrier.

15. The geared turbofan engine as recited in claim 14, wherein the carrier includes passages in communication with the oil feed opening for providing lubricant to each of the forward journal bearing and the aft journal bearing.

16. The geared turbofan engine gear system as recited in claim 10, wherein the planet gear includes an internal cavity.

17. The geared turbofan engine as recited in claim 10, wherein the planet gear includes end sections on either side of a gear section including gear teeth, the end sections include a thickness less than two (2) times a height of gear teeth in the gear section.

18. The geared turbofan engine as recited in claim 10, wherein the forward journal bearing and the aft journal bearing are made from at least one of a bronze material, a bronze coating, a bronze alloy and a copper-lead alloy.