Patent Description:
In one example application, a bearing housing for a gas turbine engine includes a bore that receives a seal. An oil tube having a flange is bolted to a boss surrounding the bore such that the seal engages the oil tube. The seal can become damaged if alignment of the seal with respect to the bore is not maintained as the seal is pushed into the bore, creating a leak subsequent to assembly.

To ensure proper seal installation, various seal installation tools have been used. One example tool is a one-piece <NUM>-D printed tool with an annular flange extending from a base, which entirely circumscribes the flange. The seal is arranged on the flange, and the base is carefully bolted to the boss, forcing the seal into the bore. However, the bolts must either be tightened simultaneously or each a little bit at a time to ensure the seal alignment is maintained.

Another seal installation tool includes a bracket that is secured to the boss using bolts. A handle is rotated to slide a block within the bracket. A separate seal pusher is arranged between the block through a hole in the bracket, which entirely circumscribes the hole. The seal is arranged on the pusher. Rotating the handle advances the pusher and seal into the bore.

An example of a an installation tool and method is described in <CIT>. That document describes a tool that is anchored to the component. The tool includes a first aperture which extends along an axis and which is coaxial with a second aperture in the component. A ring seal is pushed axially through the first aperture towards the component. The tool radially compresses the ring seal as the ring seal moves axially towards the component and the radially compressed ring seal is then pressed into the second aperture using the tool.

Both of these typical seal installation tools and the tool of <CIT> do not provide any visibility to the seal during installation and are associated with various other drawbacks.

According to a first aspect of the present invention there is provided, as recited in claim <NUM>, a method of installing a seal in a bore of a component comprising the steps securing a base plate to a component, arranging the seal onto a pusher, inserting the pusher into a hole in the base plate, installing a hub onto the base plate and over the pusher, and rotating a rod relative to the hub to advance the pusher and seat the seal in the bore. The securing step includes providing a window in the base plate that leaves the seal visible through the window subsequent to the inserting step.

In an embodiment of any of the above embodiments, the securing step includes abutting a boss of the component with the base plate and the bore in the boss. The method includes a step of clamping the base plate to the boss by securing bolts to the base plate.

In an embodiment of any of the above embodiments, the clamping step includes inserting the bolts from a side opposite the boss at an interior of the component.

In an embodiment of any of the above embodiments, the method includes the step of observing longitudinal movement of the seal past the window toward the bore.

In an embodiment of any of the above embodiments, the pusher includes first and second diameter portions that form a first shoulder. The arranging step includes sliding the seal onto the first diameter portion and into abutment with the first shoulder.

In an embodiment of any of the above embodiments, the pusher includes a third diameter portion that forms a second shoulder with the second diameter portion. The hole includes a stop that abuts the second shoulder in a fully installed seal position.

In an embodiment of any of the above embodiments, the pusher includes first and second pusher portions. The first and second diameter portions are provided on the first pusher portion. The third diameter portion is provided on the second pusher portion. The first and second pusher portions are secured to one another by a fastener.

In an embodiment of any of the above embodiments, the rotating step slides the first diameter portion into the bore in a slip fit relationship.

In an embodiment of any of the above embodiments, the installing step includes threading the hub onto a collar of the base plate.

In an embodiment of any of the above embodiments, the installing step includes receiving an end of the rod in a pocket of the pusher in a slip fit relationship.

In an embodiment of any of the above embodiments, the rotating step includes threadingly rotating the rod relative to the hub.

In an embodiment of any of the above, the rotating step includes tightening the rod until the second shoulder contacts the stop.

According to a second aspect of the present invention there is provided, as recited in claim <NUM>, a seal installation tool comprising a base plate having a hole.

In an embodiment, the seal is aligned with the window in an uninstalled seal position. In an embodiment of any of the above embodiments, the base plate includes threaded holes that are configured to receive bolts that clamp the base plate to a component having a bore that receives the seal; and a collar, and the hub is threadingly secured to the collar.

In an embodiment of any of the above embodiments, the pusher includes one or both of a third diameter portion that forms a second shoulder with the second diameter portion. The hole includes a stop that abuts the second shoulder in a fully installed seal position; and a pocket that receives an end of the rod in a slip fit relationship.

In an embodiment of any of the above embodiments, the first and second pusher portions are different materials.

In an embodiment of any of the above embodiments, the pusher includes a pocket that receives an end of the rod in a slip fit relationship.

The embodiments, examples and alternatives of the preceding paragraphs, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible. Like reference numbers and designations in the various drawings indicate like elements The scope of the invention is defined by the appended claims.

Referring to <FIG>, a component <NUM>, such as a gas turbine engine bearing housing, includes one or more bores <NUM> for communicating a fluid such as lubricating oil to the interior of the component. The component <NUM> includes a boss <NUM> providing a flat surface to which an oil tube is secured at holes <NUM>, which may be threaded or non-threaded. The bore <NUM> includes an annular recess <NUM> providing a shoulder <NUM>. A seal <NUM> is inserted into the bore <NUM> and is a small distance away from the shoulder <NUM> when in a fully installed position.

A seal installation tool <NUM> is used to insert the seal <NUM> into the bore <NUM> while maintaining desired alignment, as shown in <FIG>. The tool <NUM> includes a base plate <NUM> having standoffs <NUM> separated by a window <NUM> that provides an unobstructed view to an interior portion of the tool at an entrance to the bore <NUM>. The seal <NUM> is mounted to a pusher <NUM> supported by the base plate <NUM>. This window <NUM>, provided on each of opposing sides of the base <NUM>, for example, enables the operator to view the seal <NUM> as it moves longitudinally into the bore <NUM> during installation so that the seal <NUM> can be checked for proper alignment.

Another seal installation tool <NUM> having windows <NUM> is illustrated in <FIG>. The tool <NUM> uses a different base plate <NUM> than that of the seal installation tool <NUM>. Otherwise, all of the remaining components may be interchangeable such that a kit containing multiple base plates for a particular component may be provided.

Referring to <FIG>, the base plate <NUM> includes a hole <NUM> that receives the pusher <NUM>. The window <NUM> extends all the way to the hole <NUM> to provide visibility to an end of the pusher <NUM> on which the seal <NUM> is mounted. The base plate <NUM> is clamped to the boss <NUM> by bolts <NUM>. A threaded end <NUM> of the bolts <NUM> is received in holes <NUM>. A shank <NUM> on each bolt <NUM> has a shoulder <NUM> that engages a backside of the component <NUM>. Knobs <NUM> may be provided on the bolts <NUM> to enable hand tightening by the operator.

A collar <NUM> is provided on the base plate <NUM>, and a hub <NUM> is threadingly secured to the collar <NUM> at a threaded inner diameter <NUM> of the hub <NUM>. The hub <NUM> encloses the pusher <NUM>.

A rod <NUM> is threadingly received in a hole <NUM> of the hub <NUM> for relative rotation thereto. One end <NUM> of the rod <NUM> is received within a pocket <NUM> of the pusher <NUM> in a slip fit relationship. Another end <NUM> of the rod <NUM> is configured to cooperate with a tool, such as a torque wrench.

Referring to <FIG>, the pusher <NUM> includes first and second pusher portions <NUM>, <NUM>, which are secured to one another by a fastener <NUM> in the example. The pusher <NUM> includes first and second diameter portions <NUM>, <NUM> that form a shoulder <NUM>. The seal <NUM> is arranged on the first diameter portion <NUM> and in abutment with the shoulder <NUM>. A third diameter portion <NUM> forms a second shoulder <NUM> with the second diameter portion <NUM>. The hole <NUM> in the base plate <NUM> provides a stop <NUM> against which the second shoulder <NUM> abuts during full extension of the pusher <NUM>.

During installation, the base plate <NUM> is secured to the component <NUM> using the bolts <NUM> to clamp the base plate <NUM> to the boss <NUM>. In one example, the bolts <NUM> are inserted from a side opposite the boss <NUM> and the interior of the component <NUM>.

The seal <NUM> is arranged onto the pusher <NUM>. The pusher <NUM> is inserted into the hole <NUM> in the base plate <NUM>, and the hub <NUM> is installed onto the collar <NUM> and over the pusher <NUM>. At this point, the seal <NUM> is visible through the windows <NUM>.

The rod <NUM> is rotated relative to the hub <NUM> to advance the pusher <NUM> and seat the seal <NUM> in the bore <NUM> while maintaining desired alignment. The end <NUM> of rod <NUM> spins freely within the pocket <NUM>. During installation, the operator observes the seal <NUM> as it moves longitudinally past the window <NUM> and into the bore <NUM>. The rod <NUM> is torqued by a tool (e.g., wrench) at the end <NUM> until it the shoulder <NUM> hits stop <NUM>. This prevents the seal from rolling inward should the seal come in contact with the radius in the corner of shoulder <NUM>. The torque measurement from the wrench is used to inform a mechanic of potential damage to the seal. The tool <NUM> is removed from the boss <NUM>, and proper seal installation can be confirmed.

It should also be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit herefrom. Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated.

Although the different examples have specific components shown in the illustrations, embodiments of this invention are not limited to those particular combinations.

Claim 1:
A method of installing a seal (<NUM>) in a bore (<NUM>) of a component (<NUM>), comprising:
securing a base plate (<NUM>) to a component (<NUM>);
arranging seal (<NUM>) onto a pusher (<NUM>);
inserting the pusher (<NUM>) into a hole (<NUM>) in the base plate (<NUM>);
installing a hub (<NUM>) onto the base plate (<NUM>) and over the pusher (<NUM>); and
rotating a rod (<NUM>) relative to the hub (<NUM>) to advance the pusher (<NUM>) and seat the seal (<NUM>) in the bore (<NUM>); characterised in that:
the securing step includes providing a window (<NUM>) in the base plate (<NUM>) that leaves the seal (<NUM>) visible through the window (<NUM>) subsequent to the inserting step.