# US 11,028,728 B2 · Strut dampening assembly and method of making same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,728 B2 - Document ID: US11028728B2 - Status: Granted - Kind: B2 - Application number: 16/361,282 - Filed: 2019-03-22 - Published: 2020-09-24 - Granted: 2021-06-08 - Earliest claimed: 2019-03-22 - Assignees: Raytheon Technologies Corporation - Applicants: United Technologies Corporation - Inventors: Connor J. McGuire; Gregory Harrell; Colby S. Dunn - Web page: https://patentgrep.com/patent/US11028728B2 ## CPC - F01D 25/162: {Bearing supports} - F01D 25/164: {Flexible supports; Vibration damping means associated with the bearing} - F01D 25/04: Antivibration arrangements - F01D 25/24: Casings (modified for heating or cooling F01D25/14); Casing parts, e.g. diaphragms, casing fastenings (casings for rotary machines or engines in general F16M {; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045}) - F01D 5/16: for counteracting blade vibration - F01D 9/065: {Fluid supply or removal conduits traversing the working fluid flow, e.g. for lubrication-, cooling-, or sealing fluids (see also F01D25/16, F01D25/24 and F01D25/26)} - F05D 2230/60: Assembly methods - F05D 2240/14: Casings or housings protecting or supporting assemblies within - F05D 2240/54: Radial bearings - F05D 2260/96: Preventing, counteracting or reducing vibration or noise - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A strut includes a strut passage extending through the strut along a radial length of the strut. A tube is disposed within the strut passage and is spaced from an interior surface of the strut passage. A grommet is disposed about the tube and is in communication with the interior surface of the strut passage. The grommet defines a compressible zone including a hollow space extending radially through the grommet. The compressible zone is disposed between the tube and the interior surface of the strut passage. ## Claims ### Claim 1 A strut comprising: a strut passage extending through the strut along an axial length of the strut; a tube disposed within the strut passage and spaced from an interior surface of the strut passage; and a grommet disposed about the tube and in communication with the interior surface of the strut passage, wherein the grommet defines a compressible zone comprising a hollow space extending axially through the grommet and the hollow space is completely surrounded by the grommet along an axial extent of the hollow space; and wherein the grommet comprises a first portion disposed about and contacting a perimeter of the tube and at least one second portion extending from the first portion away from the tube, wherein the compressible zone is defined radially between an outer radial surface of the first grommet portion and an inner radial surface of the second grommet portion. ### Claim 2 (depends on 1) The strut of claim 1, wherein an outer radial surface of the second portion forms an interface with the interior surface of the strut passage. ### Claim 3 (depends on 2) The strut of claim 2, wherein the first portion is spaced from the interior surface of the strut passage. ### Claim 4 (depends on 1) The strut of claim 1, further comprising at least one retention plate projecting radially outward from the tube proximate an axial end of the grommet, the at least one retention plate configured to limit axial motion of the grommet along the tube. ### Claim 5 (depends on 1) The strut of claim 1, wherein the grommet is bonded to the tube. ### Claim 6 (depends on 1) The strut of claim 1, wherein the strut comprises an opening to the strut passage through an outer axial end of the strut. ### Claim 7 (depends on 6) The strut of claim 6, wherein the opening has a first width and the strut passage has a second width greater than the first width. ### Claim 8 (depends on 7) The strut of claim 7, wherein the grommet is configured to be compressed such that a width of the grommet is less than the first width when the grommet is in a compressed state and greater than the first width when the grommet is in an uncompressed state. ### Claim 9 A gas turbine engine comprising: an inner hub; an outer casing; and a plurality of struts extending between and connecting the inner hub to the outer casing, at least one strut of the plurality of struts comprising: a strut passage extending through the strut along an axial length of the strut; a tube disposed within the strut passage and spaced from an interior surface of the strut passage; and a grommet disposed about the tube and in communication with the interior surface of the strut passage, wherein the grommet defines a compressible zone comprising a hollow space extending axially through the grommet and the hollow space is completely surrounded by the grommet along an axial extent of the hollow space; and wherein the grommet comprises a first portion disposed about and contacting a perimeter of the tube and at least one second portion extending from the first portion away from the tube, wherein the compressible zone is defined radially between an outer radial surface of the first grommet portion and an inner radial surface of the second grommet portion. ### Claim 10 (depends on 9) The gas turbine engine of claim 9, wherein an outer radial surface of the second portion forms an interface with the interior surface of the strut passage. ### Claim 11 (depends on 9) The gas turbine engine of claim 9, further comprising at least one retention plate projecting radially outward from the tube proximate an axial end of the grommet, the at least one retention plate configured to limit axial motion of the grommet along the tube. ### Claim 12 (depends on 9) The gas turbine engine of claim 9, wherein the strut comprises an opening to the strut passage through the outer casing and an outer axial end of the strut. ### Claim 13 (depends on 12) The gas turbine engine of claim 12, wherein the opening has a first width and the strut passage has a corresponding second width greater than the first width. ### Claim 14 (depends on 13) The gas turbine engine of claim 13, wherein the grommet is configured to be compressed such that a width of the grommet is less than the first width when the grommet is in a compressed state and greater than the first width when the grommet is in an uncompressed state. ### Claim 15 A method for assembling a strut for a gas turbine engine comprising: providing a strut comprising a strut passage extending through the strut along an axial length of the strut and an opening to the strut passage through an outer axial end of the strut, the opening having a first width; attaching at least one grommet to a tube, the at least one grommet defining a compressible zone comprising a hollow space extending axially through the at least one grommet and the hollow space is completely surrounded by the at least one grommet along an axial extent of the hollow space, the grommet comprising a first portion disposed about and contacting a perimeter of the tube and at least one second portion extending from the first portion away from the tube, wherein the compressible zone is defined radially between an outer radial surface of the first grommet portion and an inner radial surface of the second grommet portion; compressing the at least one grommet such that the at least one grommet has a width less than the first width; and inserting the tube into the strut passage via the opening such that the compressible zone is disposed between the tube and an interior surface of the strut passage and the tube is spaced from the interior surface of the strut passage. ### Claim 16 (depends on 15) The method of claim 15, wherein the at least one grommet, in an uncompressed state, is in communication with the interior surface of the strut passage when the tube has been inserted into the strut passage. ### Claim 17 (depends on 15) The method of claim 15, wherein an outer radial surface of the second portion forms an interface with the interior surface of the strut passage. ### Claim 18 (depends on 17) The method of claim 17, wherein the first portion is spaced from the interior surface of the strut passage. ### Claim 19 (depends on 15) The method of claim 15, wherein the strut passage has a second width greater than the first width. ### Claim 20 (depends on 15) The method of claim 15, wherein the step of attaching the at least one grommet to the tube includes bonding the at least one grommet to the tube with an adhesive.