IP Library Granted Patent US 12,590,551
Granted Patent B1
US 12,590,551 · App. 18/896,480 · Granted Mar 31, 2026

Oil tank return for an aircraft engine oil system

Inventors: Daniel Alecu (Ottawa, CA); Marion Daniel (Verdun, CA)
Assignee: Pratt & Whitney Canada Corp.
F01M11/0004F02C7/06F01M2011/0033F05D2220/323F05D2260/98
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Quick Facts
Patent No.
US 12,590,551
App. No.
18/896,480
Granted
Mar 31, 2026
Kind
B1
Abstract

An engine oil system for an aircraft engine includes an oil tank and an oil tank return. The oil tank forms an internal oil cavity. The oil tank return forms a portion of an oil flow path through the engine oil system. The oil tank return includes a return body forming a return passage extending between and to a passage inlet and a passage outlet. The return body includes an inner diameter wall and an outer diameter wall. The inner diameter wall and the outer diameter wall form a turn of the return passage between the passage inlet and the passage outlet. The return body forms a top side, a corner, and an oblique side at the passage outlet. The corner and the oblique side are disposed at the outer diameter wall. The corner extends between the top side and the oblique side.

Claims (26)

1 . An engine oil system for an aircraft engine, the engine oil system comprising:

an oil tank forming an internal oil cavity; and

an oil tank return forming a portion of an oil flow path through the engine oil system, the oil tank return including a return body forming a return passage extending between and to a passage inlet and a passage outlet, the return body including an inner diameter wall and an outer diameter wall, the inner diameter wall and the outer diameter wall forming a turn of the return passage between the passage inlet and the passage outlet, the return body forming a top side, a corner, and an oblique side at the passage outlet, the corner and the oblique side disposed at the outer diameter wall, the corner extending between the top side and the oblique side.

2 . The engine oil system of claim 1 , wherein the oil tank includes a top wall forming a portion of the internal oil cavity, and the top side is disposed at the top wall.

3 . The engine oil system of claim 1 , wherein the oil tank return is disposed within the oil tank.

4 . The engine oil system of claim 1 , wherein the oblique side is oriented relative to the top side at an oblique angle, and the oblique angle is between 30 degrees and 60 degrees.

5 . The engine oil system of claim 1 , wherein the return body further forms an inner diameter side extending between and to the oblique side and the top side at the inner diameter wall.

6 . The engine oil system of claim 5 , wherein the corner has a first curvature radius, the inner diameter side has a second curvature radius, and the second curvature radius is greater than the first curvature radius.

7 . The engine oil system of claim 6 , wherein the second curvature radius is at least three times greater than the first curvature radius.

8 . The engine oil system of claim 6 , wherein the corner and the inner diameter side each have a circular arc shape.

9 . The engine oil system of claim 1 , wherein the passage inlet has an inlet axis, the passage outlet has an outlet plane and an outlet axis orthogonal to the outlet plane, the turn has a turn angle between the inlet axis and the outlet axis, and the turn angle is greater than 60 degrees.

10 . The engine oil system of claim 1 , wherein the passage inlet has an inlet cross-sectional area, the passage outlet has an outlet cross-sectional area, and the inlet cross-sectional area is greater than the outlet cross-sectional area.

11 . An engine oil system for an aircraft engine, the engine oil system comprising:

an oil tank including a sidewall and a top wall, the sidewall and the top wall forming an internal oil cavity; and

an oil tank return forming a portion of an oil flow path through the engine oil system, the oil tank return including a return body, the return body disposed at the top wall, the return body forming a return passage extending between and to a passage inlet and a passage outlet, the return body including an inner diameter wall and an outer diameter wall, the inner diameter wall and the outer diameter wall forming a turn of the return passage between the passage inlet and the passage outlet, the return body forming a corner and an inner diameter side at the passage outlet, the corner disposed at the outer diameter wall, the corner having a first curvature radius, the inner diameter side disposed at the inner diameter wall, the inner diameter side having a second curvature radius, the second curvature radius greater than the first curvature radius.

12 . The engine oil system of claim 11 , wherein the return body further forms a top side at the passage outlet, the top side extends between and to the corner and the inner diameter side, and the top side is substantially parallel to the top wall.

13 . The engine oil system of claim 12 , wherein the return body further forms an oblique side at the passage outlet, the oblique side extends between and to the corner and the inner diameter side, the oblique side is oriented at an oblique angle relative to the top side, and the oblique angle is greater than 30 degrees.

14 . The engine oil system of claim 11 , wherein the passage inlet has an inlet axis, the passage outlet has an outlet plane and an outlet axis orthogonal to the outlet plane, the turn has a turn angle between the inlet axis and the outlet axis, and the turn angle is greater than 60 degrees.

15 . The engine oil system of claim 1 , wherein the passage inlet has an inlet cross-sectional area, the passage outlet has an outlet cross-sectional area, and the inlet cross-sectional area is greater than the outlet cross-sectional area.

16 . An engine oil system for an aircraft engine, the engine oil system comprising:

an oil tank including a sidewall and a top wall, the sidewall and the top wall forming an internal oil cavity; and

an oil tank return forming a portion of an oil flow path through the engine oil system, the oil tank return including a return body forming a return passage extending between and to a passage inlet and a passage outlet, the passage inlet having an inlet axis, the passage outlet having an outlet plane and an outlet axis orthogonal to the outlet plane, the return body including an inner diameter wall and an outer diameter wall, the inner diameter wall and the outer diameter wall forming a turn of the return passage between the passage inlet and the passage outlet, the turn having a turn angle between the inlet axis and the outlet axis, the turn angle greater than 60 degrees, the return body forming a top side a corner at the passage outlet, the corner disposed at the top wall.

17 . The engine oil system of claim 16 , wherein the return body further forms an inner diameter side at the inner diameter wall, the corner has a first curvature radius, the inner diameter side has a second curvature radius, and the second curvature radius is greater than the first curvature radius.

18 . The engine oil system of claim 17 , wherein the second curvature radius is at least three times greater than the first curvature radius.

19 . The engine oil system of claim 17 , wherein the corner and the inner diameter side each have a circular arc shape.

20 . The engine oil system of claim 17 , wherein the corner is formed by the outer diameter wall and the inner diameter side is formed by the inner diameter wall.

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