Patent Description:
Rotational equipment typically includes one or more seal assemblies for sealing gaps between rotors and stators. A typical seal assembly includes a contact seal with a seal element such as a knife edge seal that engages a seal land. Such a contact seal can generate a significant quantity of heat that can reduce efficiency of the rotational equipment as well as subject other components of the rotational equipment to high temperatures and internal stresses. To accommodate these high temperatures and stresses, certain components of the rotational equipment may be constructed from specialty high temperature materials. However, these materials can significantly increase manufacturing and servicing costs as well as mass of the rotational equipment. While non-contact seals have been developed in an effort to reduce heat within rotational equipment, there is still room for improvement to provide an improved non-contact seal.

<CIT> discloses a prior art assembly as set forth in the preamble of claim <NUM>.

According to an aspect of the present disclosure, an assembly is provided for rotational equipment as recited in claim <NUM>.

<FIG> illustrates an assembly <NUM> for rotational equipment with an axial centerline <NUM>, which centerline <NUM> may also be an axis of rotation (e.g., a rotational axis) for one or more components of the rotational equipment assembly <NUM>. An example of such rotational equipment is a gas turbine engine for an aircraft propulsion system, an exemplary embodiment of which is described below in further detail (e.g., see <FIG>). However, the rotational equipment assembly <NUM> of the present disclosure is not limited to such aircraft nor gas turbine engine applications. The rotational equipment assembly <NUM>, for example, may alternatively be configured with rotational equipment such as an industrial gas turbine engine, a wind turbine, a water turbine or any other apparatus in which a seal is provided between a stationary structure and a rotating structure; e.g., a rotor.

The rotational equipment assembly <NUM> of <FIG> includes a stationary structure <NUM>, a rotating structure <NUM> and a seal assembly <NUM> such as, for example, a non-contact seal assembly. The seal assembly <NUM> is mounted with the stationary structure <NUM> and configured to substantially seal an annular gap between the stationary structure <NUM> and the rotating structure <NUM> as described below in further detail.

The stationary structure <NUM> includes a seal carrier <NUM>. This seal carrier <NUM> may be a discrete, unitary annular body. Alternatively, the seal carrier <NUM> may be configured with another component / portion of the stationary structure <NUM>. The seal carrier <NUM> has a seal carrier inner surface <NUM>. This seal carrier inner surface <NUM> may be substantially cylindrical. The seal carrier inner surface <NUM> extends circumferentially about (e.g., completely around) and faces towards the axial centerline <NUM>. The seal carrier inner surface <NUM> at least partially forms a bore in the stationary structure <NUM>. This bore is sized to receive the seal assembly <NUM>, which seal assembly <NUM> may be fixedly attached to the seal carrier <NUM> by, for example, a press fit connection between the seal assembly <NUM> and the seal carrier inner surface <NUM>. The seal assembly <NUM>, of course, may also or alternatively be fixedly attached to the seal carrier <NUM> using one or more other techniques / devices.

The rotating structure <NUM> includes a rotating seal land <NUM>. This rotating seal land <NUM> may be a discrete, unitary annular body. For example, the rotating seal land <NUM> may be mounted to a shaft of the rotating structure <NUM>. Alternatively, the rotating seal land <NUM> may be configured with another component / portion of the rotating structure <NUM>. For example, the rotating seal land <NUM> may be an integral part of a shaft of the rotating structure <NUM>, or another component mounted to the shaft.

The rotating seal land <NUM> of <FIG> has an outer seal land surface <NUM>. This outer seal land surface <NUM> may be substantially cylindrical. The outer seal land surface <NUM> extends circumferentially about (e.g., completely around) and faces away from the axial centerline <NUM>. The outer seal land surface <NUM> is configured to face towards and may be axially aligned with the seal carrier inner surface <NUM>. While <FIG> illustrates the outer seal land surface <NUM> and the seal carrier inner surface <NUM> with approximately equal axial lengths along the axial centerline <NUM>, the outer seal land surface <NUM> may alternatively be longer or shorter than the seal carrier inner surface <NUM> in other embodiments.

The seal assembly <NUM> includes a primary seal device <NUM> and one or more secondary seal devices <NUM>. The seal assembly <NUM> also includes one or more additional components for positioning, supporting and/or mounting one or more of the seal devices <NUM> and/or <NUM> with the stationary structure <NUM>. The seal assembly <NUM> of <FIG>, for example, includes a first (e.g., secondary seal assembly) ring structure <NUM> configured for positioning, supporting and/or mounting the secondary seal devices <NUM> relative to the primary seal device <NUM>. The one or more secondary seal devices <NUM> and the first ring structure <NUM> may collectively provide a secondary seal assembly <NUM>. The first ring structure <NUM> may also be configured for axially positioning and/or supporting an axial first side <NUM> of the primary seal device <NUM> relative to the stationary structure <NUM>.

The seal assembly <NUM> of <FIG> also includes a second (e.g., primary seal device) ring structure <NUM> configured for axially positioning and/or supporting an axial second side <NUM> of the primary seal device <NUM> relative to the stationary structure <NUM>. This second ring structure <NUM> extends axially along the axial centerline <NUM> between a first side <NUM> and a second side <NUM>. The second ring structure <NUM> extends circumferentially about (e.g., completely around) the axial centerline <NUM>.

The second ring structure <NUM> of <FIG> is permanently connected to (e.g., formed integral with, bonded to, etc.) the stationary structure <NUM> and its seal carrier <NUM>. The second ring structure <NUM>, for example, may be formed with the seal carrier <NUM> in a single monolithic body <NUM>. Herein, the term "monolithic" may describe a body which is formed as a unitary structure. The second ring structure <NUM> and the seal carrier <NUM>, for example, may be collectively cast, machined, additively manufactured and/or otherwise formed together to provide the monolithic body <NUM>. By contrast, a non-monolithic body includes a plurality of discretely formed members which are mechanically fastened and/or otherwise removably attached together following their formation. Referring again to <FIG>, the second ring structure <NUM> is configured as an annular and/or castellated shoulder of the stationary structure <NUM>, which projects radially inward from the seal carrier <NUM> to a distal inner end <NUM>.

Referring to <FIG>, the second ring structure <NUM> may alternatively be configured discrete from the stationary structure <NUM> and its seal carrier <NUM>. The second ring structure <NUM> of <FIG>, for example, is fixedly attached to the seal carrier <NUM> by, for example, a press fit connection between the second ring structure <NUM> and the seal carrier inner surface <NUM>. The second ring structure <NUM>, of course, may also or alternatively be fixedly attached to the seal carrier <NUM> using one or more other techniques / devices. Here, the second ring structure <NUM> is configured as a scalloped support ring / plate mated with (e.g., nested with) the seal carrier <NUM>.

Referring to <FIG>, the primary seal device <NUM> is configured as an annular seal device such as, but not limited to, a non-contact hydrostatic seal device. The primary seal device <NUM> includes a seal base <NUM>, a plurality of seal shoes <NUM> and a plurality of spring elements <NUM> (see also <FIG> and <FIG>).

The seal base <NUM> may be configured as an annular full hoop body. The seal base <NUM> of <FIG> extends circumferentially about (e.g., completely around) the axial centerline <NUM>. The seal base <NUM> is configured to extend circumferentially around and thereby circumscribe and support the seal shoes <NUM> as well as the spring elements <NUM>. Referring to <FIG>, the seal base <NUM> extends axially along the axial centerline <NUM> between and at least partially or completely forms the first side <NUM> and the second side <NUM>. The seal base <NUM> extends radially between an inner side <NUM> of the seal base <NUM> and an outer side <NUM> of the seal base <NUM>. The seal base outer side <NUM> radially engages (e.g., is press fit against or otherwise contacts) the stationary structure <NUM> and its inner surface <NUM> as shown in <FIG>, where the stationary structure <NUM> and its seal carrier <NUM> extend circumferentially about (e.g., circumscribe) the seal base <NUM>.

Referring to <FIG>, the seal shoes <NUM> may be configured as arcuate bodies and are arranged circumferentially around the axial centerline <NUM> in an annular array. Each seal shoe <NUM>, for example, is arranged circumferentially between and next to a pair of adjacent circumferentially neighboring seal shoes <NUM>. The annular array of the seal shoes <NUM> extends circumferentially about (e.g., completely around) the axial centerline <NUM>, thereby forming an inner bore at an inner side <NUM> of the primary seal device <NUM>. As best seen in <FIG>, the inner bore is sized to receive the rotating seal land <NUM>, where the rotating structure <NUM> projects axially through (or into) the inner bore formed by the seal shoes <NUM>.

Referring to <FIG>, each of the seal shoes <NUM> extends radially from the inner side <NUM> of the primary seal device <NUM> to an outer side <NUM> of that seal shoe <NUM>. Each of the seal shoes <NUM> extends circumferentially about the axial centerline <NUM> between opposing circumferential first and second ends <NUM> and <NUM> of that seal shoe <NUM>. Referring to <FIG>, each of the seal shoes <NUM> extends axially along the axial centerline <NUM> between an axial first (e.g., upstream and/or high pressure) end <NUM> of the seal shoe <NUM> and an axial second (e.g., downstream and/or low pressure) end <NUM> of the seal shoe <NUM>. The axial seal shoe first end <NUM> may be an upstream and/or high pressure end relative, for example, to flow of leakage fluid across the primary seal device <NUM>. The axial seal shoe first end <NUM> is axially offset / displaced from the axial first side <NUM>. The axial seal shoe second end <NUM> may be a downstream and/or low pressure end relative, for example, to the flow of leakage fluid across the primary seal device <NUM>. The axial seal shoe second end <NUM> may be generally axially aligned with the axial second side <NUM>. The seal shoes <NUM> of the present disclosure, however, are not limited to such exemplary relationships.

Each of the seal shoes <NUM> includes a seal shoe base <NUM> and one or more seal shoe protrusions 82A-D (generally referred to as "<NUM>"); inner projections such as rails and/or teeth. The seal shoe base <NUM> is disposed at (e.g., on, adjacent or proximate) the seal shoe outer side <NUM>. The seal shoe base <NUM> of <FIG>, for example, includes a (e.g., arcuate) base outer surface <NUM> at the seal shoe outer side <NUM>. Referring to <FIG>, the seal shoe base <NUM> extends radially between the base outer surface <NUM> and one or more (e.g., arcuate) base inner surfaces <NUM>. Each of these base inner surfaces <NUM> may be an arcuate surface. Referring to <FIG>, the seal shoe base <NUM> extends circumferentially about the axial centerline <NUM> between the seal shoe first end <NUM> and the seal shoe second end <NUM>. The seal shoe base <NUM> includes a first end surface <NUM> at the seal shoe first end <NUM> and a second end surface <NUM> at the seal shoe second end <NUM>. Each of the end surfaces <NUM> and <NUM> may be a flat planar surface. Each of the end surfaces <NUM> and <NUM>, for example, may have a straight sectional geometry when viewed, for example, in a reference plane perpendicular to the axial centerline <NUM>; e.g., the plane of <FIG>. Referring to <FIG>, the seal shoe base <NUM> extends axially between the seal shoe first side <NUM> and the seal shoe second side <NUM>.

The seal shoe base <NUM> includes a (e.g., arcuate) side surface <NUM> generally at the seal shoe first side <NUM>. In the array, these side surfaces <NUM> collectively form a generally annular, but circumferentially segmented, side surface configured for sealingly engaging with (e.g., contacting) the secondary seal devices <NUM> as shown in <FIG>. The seal shoes <NUM> of the present disclosure, however, are not limited to the foregoing exemplary configuration.

Referring to <FIG>, the seal shoe protrusions <NUM> are arranged at discrete axial locations along the axial centerline <NUM> and the seal shoe base <NUM>. Each pair of axially adjacent / neighboring protrusions <NUM> may thereby be axially separated by an (e.g., arcuate) inter-protrusion gap. The seal shoe protrusions <NUM> of <FIG> are configured parallel to one another.

The seal shoe protrusions <NUM> may be arranged in a concentrated grouping <NUM>. This grouping <NUM> may be asymmetrically arranged axially along the axial centerline <NUM> between the seal shoe first side <NUM> and the seal shoe second side <NUM>. For example, an axial center <NUM> (e.g., midpoint) of the grouping <NUM> of the seal shoe protrusions <NUM> in <FIG> is arranged closer to the seal shoe first side <NUM> than the seal shoe second side <NUM>. More particularly, the axial center <NUM> is disposed axially between the seal shoe first side <NUM> and an axial center <NUM> (e.g., midpoint) of the respective seal shoe <NUM> and its seal shoe base <NUM>. Thus, one or more or each of the seal shoe protrusions <NUM> (e.g., protrusions 82A-C) may be located axially along the axial centerline <NUM> between the seal shoe first side <NUM> and the axial center <NUM>. The seal shoe protrusions <NUM> of the present disclosure, however, are not limited to the foregoing exemplary asymmetric configuration.

The seal shoe protrusions <NUM> are connected to (e.g., formed integral with or otherwise attached to) the seal shoe base <NUM>. Each of the seal shoe protrusions <NUM> projects radially inwards from the seal shoe base <NUM> and its base inner surfaces <NUM> to a distal protrusion end. Each of the seal shoe protrusions <NUM> has a protrusion inner surface 100A-D (generally referred to as "<NUM>") at the distal protrusion end. One or more or each of the protrusion inner surfaces <NUM> may also be at the inner side <NUM> of the primary seal device <NUM>. Each protrusion inner surface <NUM> may be an arcuate surface. Each protrusion inner surface <NUM>, for example, may have an arcuate sectional geometry when viewed, for example, in a reference plane perpendicular to the axial centerline <NUM>; e.g., the plane of <FIG>. The protrusion inner surfaces <NUM> are configured to be arranged in close proximity with (but not touch) and thereby sealingly mate with the outer seal land surface <NUM> in a non-contact manner (see <FIG>), where the rotating structure <NUM> projects axially through (or into) the inner bore formed by the seal shoes <NUM>.

Each of the seal shoe protrusions <NUM> extends axially between opposing projection end surfaces <NUM>. Each of these end surfaces <NUM> extends radially between and may be contiguous with a respective one of the projection inner surfaces <NUM> and a respective one of the base inner surfaces <NUM>.

Each of the seal shoe protrusions <NUM> of <FIG> has the same radial height. One or more of the seal shoe protrusions <NUM>, however, may alternatively have a different radial height than at least another one of the seal shoe protrusions <NUM>.

Referring to <FIG>, the spring elements <NUM> are arranged circumferentially about the axial centerline <NUM> in an annular array. Referring to <FIG> and <FIG>, the spring elements <NUM> are also arranged (e.g., radially) between the seal shoes <NUM> and the seal base <NUM>. Each of the spring elements <NUM> is configured to moveably and resiliently connect a respective one of the seal shoes <NUM> to the seal base <NUM>.

The spring element <NUM> of <FIG> includes inner and outer mounts <NUM> and <NUM> (e.g., inner and outer radial fingers / projections) and one or more spring beams 108A and 108B (generally referred to as "<NUM>"). The inner mount <NUM> may be directly or indirectly connected to (e.g., formed integral with or otherwise attached to) a respective one of the seal shoes <NUM> and its seal shoe base <NUM> at the circumferential seal shoe first end <NUM>, where the opposing circumferential seal shoe second end <NUM> is free floating; e.g., the seal shoe <NUM> is cantilevered from the inner mount <NUM>. The inner mount <NUM> projects radially outward from the respective seal shoe <NUM> and its seal shoe base <NUM>.

The outer mount <NUM> may be directly or indirectly connected to the seal base <NUM>, and is generally circumferentially aligned with or near the circumferential seal shoe second end <NUM>. The outer mount <NUM> is therefore disposed a circumferential distance from the inner mount <NUM>. The outer mount <NUM> projects radially inward from the seal base <NUM>.

The spring beams <NUM> are configured as resilient, biasing members of the primary seal device <NUM>. The spring beams <NUM> of <FIG>, for example, are configured as cantilevered-leaf springs. These spring beams <NUM> may be radially stacked and spaced apart from one another so as to form a four bar linkage with the inner mount <NUM> and the outer mount <NUM>. More particularly, each of the spring beams <NUM> may be directly or indirectly connected to the inner mount <NUM> and the outer mount <NUM>. Each of the spring beams <NUM> extends laterally (e.g., circumferentially or tangentially) between and to the inner mount <NUM> and the outer mount <NUM>. The spring beams <NUM> of <FIG> may thereby laterally overlap a major circumferential portion (e.g., ~<NUM>-<NUM>%) of the respective seal shoe <NUM>.

During operation of the primary seal device <NUM> of <FIG>, rotation of the rotating structure <NUM> may develop aerodynamic forces and apply a fluid pressure to the seal shoes <NUM> causing each seal shoe <NUM> to respectively move radially up and down relative to the outer seal land surface <NUM>. The fluid velocity may increase as a gap between a respective seal shoe <NUM> and the outer seal land surface <NUM> increases, thus reducing pressure in the gap and drawing the seal shoe <NUM> radially inwardly toward the outer seal land surface <NUM>. As the gap closes, the velocity may decrease and the pressure may increase within the gap, thus, forcing the seal shoe <NUM> radially outwardly from the outer seal land surface <NUM>. The respective spring element <NUM> and its spring beams <NUM> may deflect and move with the seal shoe <NUM> to enable provision of a primary seal of the gap between the outer seal land surface <NUM> and seal shoe protrusions <NUM> within predetermined design tolerances.

While the primary seal device <NUM> described above is operable to generally seal the annular gap between the stationary structure <NUM> and the rotating structure <NUM>, the fluid (e.g., gas) may still flow axially through passages 110A-C (generally referred to as "<NUM>") defined by radial air gaps between the elements <NUM>, 108A, 108B and <NUM>. The secondary seal assembly <NUM> and its one or more secondary seal devices <NUM> therefore are provided to seal off these passages <NUM> and, thereby, further and more completely seal the annular gap.

Each of the secondary seal devices <NUM> may be configured as a ring seal element such as, but not limited to, a split ring. Alternatively, one or more of the secondary seal devices <NUM> may be configured as a full hoop body ring, an annular brush seal or any other suitable ring-type seal.

The secondary seal devices <NUM> of <FIG> are arranged together in an axial stack. In this stack, each of the secondary seal devices <NUM> axially engages (e.g., contacts) another adjacent one of the secondary seal devices <NUM>. The stack of the secondary seal devices <NUM> is arranged with the first ring structure <NUM>, which positions and mounts the secondary seal devices <NUM> with the stationary structure <NUM> adjacent the primary seal device <NUM>. In this arrangement, the stack of the secondary seal devices <NUM> is operable to axially engage (e.g., contact) and form a seal between one or more or each of the first side surfaces <NUM> of the seal shoes <NUM> and an annular surface <NUM> of the first ring structure <NUM>. These surfaces <NUM> and <NUM> are axially aligned with one another, which enables the stack of the secondary seal devices <NUM> to slide radially against, but maintain a seal engagement with, one or more or each of the side surfaces <NUM> as the seal shoes <NUM> move radially relative to the outer seal land surface <NUM> as described above.

The first ring structure <NUM> may include a secondary seal device support ring <NUM> and a retention ring <NUM>. The support ring <NUM> is configured with an annular full hoop body, which extends circumferentially around the axial centerline <NUM>. The support ring <NUM> includes the annular surface <NUM>, and is disposed axially adjacent and may be axially engaged with (e.g., contacts, abutted against, etc.) the seal base <NUM> at its first side <NUM>.

The retention ring <NUM> is configured with an annular full hoop body, which extends circumferentially around the axial centerline <NUM>. The retention ring <NUM> is disposed axially adjacent and is engaged with (e.g., axially contacts, abutted against) the support ring <NUM>, thereby capturing the stack of the secondary seal devices <NUM> within an annular channel <NUM> formed between the rings <NUM> and <NUM>. The stack of the secondary seal devices <NUM>, of course, may also or alternatively be attached to one of the rings <NUM>, <NUM> by, for example, a press fit connection and/or otherwise.

The seal assembly <NUM> is configured with a small clearance gap <NUM> axially between the seal shoes <NUM> and the second ring structure <NUM> when the rotating structure <NUM> is at rest. However, under engine operating conditions, a pressure differential is applied axially across the seal assembly <NUM>. Under certain conditions, this pressure differential may deflect the primary seal device <NUM> and shift one or more of the seal shoes <NUM> axially towards the second ring structure <NUM>. The clearance gap <NUM> is sized to account for such axial shifts of the seal shoe(s) <NUM>. For example, when the seal shoes <NUM> axially shift, one or more of the seal shoes <NUM> may axially contact (e.g., rub radially along) the first side <NUM> of the second ring structure <NUM>. Where the clearance gap <NUM> is too small, friction forces between the seal shoe(s) <NUM> and the second ring structure <NUM> may significantly impede or prevent vertical movement of the respective seal shoe(s) <NUM>. Where the clearance gap <NUM> is too large, frictional forces between the seal shoe(s) <NUM> and the second ring structure <NUM> may be relatively small or non-existent; e.g., where the seal shoe(s) <NUM> are too far away to contact the second ring structure <NUM>. Such small or zero friction forces may lead to excessive vibrations (e.g., flutter) in the respective seal shoe(s) <NUM>; e.g., where the rubbing does not damp the vibrations.

The size of the clearance gap <NUM> may be difficult to accurately control due to manufacturing tolerances and deviations. To accommodate such deviation, referring to <FIG> and <FIG>, the seal assembly <NUM> of the present disclosure includes one or more primary seal device axial locators <NUM>. Each of these locators <NUM> may be configured as a fastener such as, but not limited to, a set screw, a bolt, a pin, etc. Each locator <NUM> is mated with (e.g., threaded into, inserted into, etc.) a respective locator receptacle <NUM> (e.g., a fastener aperture) in the second ring structure <NUM>, where each locator receptacle <NUM> of <FIG> extends axially through the second ring structure <NUM> between the sides <NUM> and/or <NUM>. Each locator <NUM> of <FIG>, for example, is threaded into the respective locator receptacle <NUM> such that the locator <NUM> projects axially out from the second ring structure <NUM> and its first side <NUM> to a distal end <NUM> that axially abuts (e.g., contacts, presses against) the primary seal device <NUM>; e.g., the seal base <NUM> and/or a respective one of the outer mounts <NUM>.

The locators <NUM> are configured to axially locate the primary seal device <NUM> relative to the second ring structure <NUM> in order to provide the clearance gap <NUM> with a predetermined / desired axial width. For example, where the clearance gap <NUM> is too small or non-existent, one or more or all of the locators <NUM> may each be turned (e.g., screwed into the second ring structure <NUM>) to push the primary seal device <NUM> and its element(s) <NUM> and/or <NUM> axially away from the second ring structure <NUM> (or vice versa where, for example, the second ring structure <NUM> is discrete from the seal carrier <NUM> as shown see <FIG>). A gap <NUM> may thereby be formed axially between the second ring structure <NUM> and the primary seal device <NUM> and its element(s) <NUM> and/or <NUM>, where the locator(s) <NUM> extend axially through that gap <NUM> to the primary seal device <NUM> and its element(s) <NUM> and/or <NUM>. Once the locators <NUM> are adjusted to provide the desired clearance gap <NUM> between the seal shoes <NUM> and the second ring structure <NUM>, one or more or all of the locators <NUM> may be (e.g., axially and rotatably) fixed to the second ring structure <NUM>. Each locator <NUM>, for example, may be welded, brazed and/or otherwise bonded to the second ring structure <NUM> to lock its position.

While each locator <NUM> may press axially against the primary seal device <NUM>, that locator <NUM> need not (but may) project into the primary seal device <NUM>. The primary seal device <NUM> of <FIG>, for example, does not include an aperture (e.g., through-hole, recess, slot, etc.) to specifically mate with or otherwise receive one of the locators <NUM>. Rather, the locator <NUM> of <FIG> axially engages an axially exterior surface at the side <NUM> of the primary seal device <NUM> and its element(s) <NUM> and/or <NUM>. Furthermore, each locator <NUM> may only be mated with (e.g., project into, thread into, etc.) the respective locator receptacle <NUM> in the second ring structure <NUM> and not any other structure. In other words, while the locators <NUM> are configured to axially locate the primary seal device <NUM> relative to the second ring structure <NUM>, the locators <NUM> need not (but may) be used to fasten the second ring structure <NUM> to another body. A head <NUM> of each locator <NUM> in <FIG> may thereby be exposed to an open plenum <NUM> axially adjacent the second ring structure <NUM> and its second side <NUM>.

In some embodiments, as best seen in <FIG> and <FIG>, the primary seal device <NUM> and some or all of its elements (e.g., <NUM>-<NUM>) may be configured as a monolithic body. However, the present disclosure is not limited to such a primary seal device construction.

As described above, the rotational equipment assembly <NUM> of the present disclosure may be configured with various different types and configurations of rotational equipment. <FIG> illustrates one such type and configuration of the rotational equipment - a geared turbofan gas turbine engine <NUM>. This turbine engine <NUM> includes various stationary structures (e.g., bearing supports, hubs, cases, etc.) as well as various rotors (e.g., rotor disks, shafts, shaft assemblies, etc.) as described below, where the stationary structure <NUM> and the rotating structure <NUM> can respectively be configured as anyone of the foregoing structures in the turbine engine <NUM> of <FIG>, or other structures not mentioned herein.

The turbine engine <NUM> of <FIG> extends along the axial centerline <NUM> between an upstream airflow inlet <NUM> and a downstream airflow exhaust <NUM>. The turbine engine <NUM> includes a fan section <NUM>, a compressor section <NUM>, a combustor section <NUM> and a turbine section <NUM>. The compressor section <NUM> of <FIG> includes a low pressure compressor (LPC) section 141A and a high pressure compressor (HPC) section 141B. The turbine section <NUM> of <FIG> includes a high pressure turbine (HPT) section 143A and a low pressure turbine (LPT) section 143B.

The engine sections <NUM>, 141A, 141B, <NUM>, 143A and 143B are arranged sequentially along the axial centerline <NUM> within an engine housing <NUM>. This engine housing <NUM> includes an inner case <NUM> (e.g., a core case) and an outer case <NUM> (e.g., a fan case). The inner case <NUM> may house one or more of the engine sections 141A, 141B, <NUM>, 143A and 143B; e.g., an engine core. The outer case <NUM> may house at least the fan section <NUM>.

Each of the engine sections <NUM>, 141A, 141B, 143A and 143B includes a respective bladed rotor <NUM>-<NUM>. Each of these bladed rotors <NUM>-<NUM> includes a plurality of rotor blades arranged circumferentially around and connected to one or more respective rotor disks. The rotor blades, for example, may be formed integral with or mechanically fastened, welded, brazed, adhered and/or otherwise attached to the respective rotor disk(s).

The fan rotor <NUM> is connected to a gear train <NUM>, for example, through a fan shaft <NUM>. The gear train <NUM> and the LPC rotor <NUM> are connected to and driven by the LPT rotor <NUM> through a low speed shaft <NUM>. The HPC rotor <NUM> is connected to and driven by the HPT rotor <NUM> through a high speed shaft <NUM>. The shafts <NUM>-<NUM> are rotatably supported by a plurality of bearings <NUM>. Each of these bearings <NUM> is connected to the engine housing <NUM> by at least one stationary structure such as, for example, an annular support strut.

During operation, air enters the turbine engine <NUM> through the airflow inlet <NUM>. This air is directed through the fan section <NUM> and into a core gas path <NUM> and a bypass gas path <NUM>. The core gas path <NUM> extends sequentially through the engine sections 141A, 141B, <NUM>, 143A and 143B. The air within the core gas path <NUM> may be referred to as "core air". The bypass gas path <NUM> extends through a bypass duct, which bypasses the engine core. The air within the bypass gas path <NUM> may be referred to as "bypass air".

The core air is compressed by the LPC rotor <NUM> and the HPC rotor <NUM> and directed into a combustion chamber <NUM> of a combustor in the combustor section <NUM>. This fuel air mixture is ignited and combustion products thereof flow through and sequentially cause the HPT rotor <NUM> and the LPT rotor <NUM> to rotate. The rotation of the HPT rotor <NUM> and the LPT rotor <NUM> respectively drive rotation of the HPC rotor <NUM> and the LPC rotor <NUM> and, thus, compression of the air received from a core airflow inlet. The rotation of the LPT rotor <NUM> also drives rotation of the fan rotor <NUM>, which propels bypass air through and out of the bypass gas path <NUM>.

The rotational equipment assembly <NUM> may be included in various turbine engines other than the one described above as well as in other types of rotational equipment. The rotational equipment assembly <NUM>, for example, may be included in a geared turbine engine where a gear train connects one or more shafts to one or more rotors in a fan section, a compressor section and/or any other engine section. Alternatively, the rotational equipment assembly <NUM> may be included in a turbine engine configured without a gear train. The rotational equipment assembly <NUM> may be included in a geared or non-geared turbine engine configured with a single spool, with two spools (e.g., see <FIG>), or with more than two spools. The turbine engine may be configured as a turbofan engine, a turbojet engine, a propfan engine, a pusher fan engine, an auxiliary power unit (APU) or any other type of turbine engine. The present disclosure therefore is not limited to any particular types or configurations of turbine engines or rotational equipment.

Claim 1:
An assembly (<NUM>) for rotational equipment, comprising:
a seal device (<NUM>) including:
a plurality of seal shoes (<NUM>) arranged around a centerline (<NUM>) in an annular array, the plurality of seal shoes (<NUM>) comprising a first seal shoe (<NUM>);
a seal base (<NUM>) circumscribing the annular array; and
a plurality of spring elements (<NUM>) comprising a first spring element (<NUM>), the first spring element (<NUM>) connecting and extending between the first seal shoe (<NUM>) and the seal base (<NUM>);
a ring structure (<NUM>) axially adjacent the seal device (<NUM>), the ring structure (<NUM>) comprising a fastener aperture (<NUM>) extending axially through the ring structure (<NUM>); and
a fastener (<NUM>) mated with the fastener aperture (<NUM>), wherein the fastener (<NUM>) is abutted axially against the seal device (<NUM>);
characterised in that
the fastener (<NUM>) axially engages an axially exterior surface at a side (<NUM>) of the seal base (<NUM>).