IP Library Granted Patent US 12,421,901
Granted Patent B2
US 12,421,901 · App. 18/435,985 · Granted Sep 23, 2025

Carbon radial seal

Inventors: Jonathan L. Miller (Belchertown, MA); Jonathan F. Zimmitti (Glastonbury, CT); Christopher Charles Killian (Coatesville, PA); Bryan Richard Camerlin (Bozeman, MT)
Assignee: RTX Corporation
F02C7/28F16J15/34
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12,421,901
App. No.
18/435,985
Granted
Sep 23, 2025
Kind
B2
Abstract

A machine has: an outer member; an inner member having an outer diameter (OD) surface; and a seal system. A seal housing is mounted to the outer member and has first and second walls; a first seal stage contacting the OD surface and the first wall; a second seal stage contacting the OD surface and the second wall; and a wave spring biasing the seal stages axially apart from each other. The seal stages each have a plurality of seal segments interfitting end to end and each having: a first end; a second end circumferentially opposite the first end; a first face; a second face axially opposite the first face; an inner diameter (ID) face; and an outer diameter (OD) face having a radially protruding lug. The housing has an inner diameter (ID) surface having recesses receiving the lugs of the seal stages to circumferentially retain the seal stages.

Claims (73)

1. A machine comprising:

an outer member;

an inner member having an outer diameter (OD) surface; and

a seal system comprising:

a seal housing mounted to the outer member and having a first wall and a second wall;

a first seal stage contacting the inner member outer diameter (OD) surface and the first wall;

a second seal stage contacting the inner member outer diameter (OD) surface and the second wall; and

a wave spring biasing the first and second seal stages axially apart from each other, wherein:

the first seal stage comprises a plurality of seal segments interfitting end to end and each segment having:

a first end;

a second end circumferentially opposite the first end;

a first face;

a second face axially opposite the first face;

an inner diameter (ID) face; and

an outer diameter (OD) face having a circumferential groove and a single radially protruding lug;

the second seal stage comprises a plurality of seal segments interfitting end to end and each segment having:

a first end;

a second end circumferentially opposite the first end;

a first face;

a second face axially opposite the first face;

an inner diameter (ID) face; and

an outer diameter (OD) face having a circumferential groove and a single radially protruding lug, the radially protruding lug between the circumferential groove and the second face;

for the segments of the first stage and the second stage the outer diameter (OD) face has respective radial reliefs at a first circumferential end and a second circumferential end of the protruding lug;

the first stage and the second stage each comprise a garter spring holding the seal segments together; and

the housing further comprises:

an inner diameter (ID) surface having a plurality of recesses receiving the lugs of the first stage and the second stage to circumferentially retain the first stage and the second stage.

2. The machine of claim 1 wherein for the segments of the first stage and the second stage:

the protruding lug has a height of 2.5 mm to 5.0 mm and a width of 15.0 mm to 18.0 mm and an axial span of 40% to 60%, an axial span of the segment.

3. The machine of claim 1 wherein for the segments of the first stage and the second stage:

the protruding lug axial span is 3.0 mm to 4.5 mm.

4. The machine of claim 1 wherein for the segments of the first stage and the second stage:

the protruding lug has a height of 2.0 mm to 5.0 mm and a width of 10.0 mm to 20.0 mm and an axial span of 40% to 60%, an axial span of the segment.

5. The machine of claim 1 wherein the segments of the first stage and the second stage are in a non-archbound condition.

6. The machine of claim 1 wherein:

the segments of the first stage are identical to the segments of the second stage.

7. The machine of claim 1 wherein for the segments of the first stage and the second stage:

the radial reliefs are concavities.

8. The machine of claim 1 further comprising:

a first annular plate between the wave spring and the first seal stage; and

a second annular plate between the wave spring and the second seal stage.

9. The machine of claim 1 further comprising:

a bearing in a bearing compartment and supporting the inner member for rotation relative to the outer member; and

a buffer chamber, the seal system isolating the bearing compartment from the buffer chamber.

10. The machine of claim 1 wherein:

the plurality of seal segments of the first stage and the second stage are a majority by weight carbon.

11. The machine of claim 1 being a gas turbine engine wherein:

the inner member is a shaft and the outer member is static structure.

12. The machine of claim 11 wherein:

the shaft is a high spool shaft.

13. The machine of claim 1 wherein for the segments of the first stage and the second stage:

the outer diameter (OD) face has a circumferential groove;

the first face has:

a circumferential channel closer to the ID face than the OD face; and

a plurality of channels extending from the circumferential channel to the OD face; and

the ID face has:

a circumferential channel closer to the first face than the second face; and

a plurality of channels extending from the circumferential channel to the second face.

14. The machine of claim 13 wherein:

the radially protruding lug is between the outer diameter (OD) face circumferential groove and the second face.

15. The machine of claim 13 wherein for the segments of the first stage and the second stage:

the segments of the first stage are identical to the segments of the second stage.

16. The machine of claim 15 wherein for the segments of the first stage and the second stage:

the seal segment is a majority by weight carbon.

17. The machine of claim 13 wherein for the segments of the first stage and the second stage:

the seal segment is a majority by weight carbon.

18. A method for using the machine of claim 1 , the method comprising:

driving rotation of the inner member relative to the outer member; and

the recesses engaging the associated received lugs of the first stage and the second stage to circumferentially retain the first stage and the second stage relative to the outer member.

19. The method of claim 18 wherein:

the machine is a gas turbine engine and the inner member is a high speed shaft assembly; and

the driving comprises running the engine.

20. The method of claim 18 wherein:

the plurality of seal segments of the first stage and the second stage are a majority by weight carbon.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 2, 2024
From: MILLER, JONATHAN L.; ZIMMITTI, JONATHAN F.; KILLIAN, CHRISTOPHER CHARLES; CAMERLIN, BRYAN RICHARD
To: RTX CORPORATION
Reel/Frame 067893/0908 →
Continuity (2)
Provisional Application 63444112 · Feb 8, 2023
Related Publication 20250109711A1 · Apr 3, 2025
References Cited (23)
US 2085457A · Westerhouse · 1937 [cited by examiner]
US 3784213A · Voitik · 1974 [cited by applicant]
US 4417734A · Sundberg · 1983 [cited by applicant]
US 4754984A · Keba · 1988 [cited by examiner]
US 5058904A · Nevola · 1991 [cited by applicant]
US 6679678B2 · Giesler et al. · 2004 [cited by applicant]
US 9004495B2 · Vasagar · 2015 [cited by examiner]
US 9194424B2 · Garrison · 2015 [cited by applicant]
US 9890650B2 · Von Berg et al. · 2018 [cited by applicant]
US 9970549B2 · Miller · 2018 [cited by applicant]
US 10024435B2 · Manry · 2018 [cited by applicant]
US 11287043B2 · Manry · 2022 [cited by applicant]
US 11365640B2 · Davis · 2022 [cited by applicant]
US 20080053107A1 · Weaver · 2008 [cited by examiner]
US 20150049968A1 · Garrison · 2015 [cited by examiner]
US 20160010483A1 · Miller · 2016 [cited by examiner]
US 20160258564A1 · Fukumoto · 2016 [cited by examiner]
US 20170362949A1 · Von Berg · 2017 [cited by examiner]
US 20190264814A1 · Manry · 2019 [cited by examiner]
US 20210190208A1 · Berard et al. · 2021 [cited by applicant]
US 20220195889A1 · Lefebvre · 2022 [cited by applicant]
EP 3263842A1 · 2018 [cited by applicant]
Brian P. Roche, “Bulkhead Seals—A Sealing Solution”, Paper presented at the SNAME 11th Propeller and Shafting Symposium, Sep. 12, 2006, Paper No. SNAME-PSS-2006-14, Society of Naval Architects and Marine Engineers, Alex… [cited by applicant]