US-12618499-B2 - Gimbals and their manufacture

Abstract

A gimbal for connecting pipes having a core portion and at least one joint shield portion that surrounds the core portion. The core portion, which has a core portion internal surface and a core portion external surface, has at least two pipe engaging portions that are separated by at least one flexible portion, which has a flexible portion internal surface and a flexible portion external surface, and a plurality of joint cover portions. Each joint cover portion extends from the core portion external surface of the core portion to provide a protective cover for the flexible portion external surface of at least one flexible portion of the core portion and is pivotably connected to a least one joint shield portion. The shield portion is configured to provide a protective shield for at least one flexible portion of the core portion.

Inventors

• Alok Gupta
• Daniel J. COUSINS
• Andrea L. BALL

Assignees

• ROLLS-ROYCE PLC

Dates

Publication Date

20260505

Application Date

20201210

Priority Date

20191217

Claims (20)

1. 1 . A gimbal for connecting pipes, the gimbal comprising: a core portion that comprises (i) at least two pipe engaging portions that are separated by at least one flexible portion, and (ii) a plurality of joint cover portions that each extend from an external surface of the core portion and provide a protective cover for an external surface of the at least one flexible portion; and at least one joint shield portion that surrounds the core portion to provide a protective shield for the at least one flexible portion, and includes a plurality of pin portions that are integrally formed therewith as a single piece, wherein each of the plurality of pin portions interlocks with a respective one of the plurality of joint cover portions to pivotably connect the at least one joint shield portion to the joint cover portions; and the core portion, including the joint cover portions, and the at least one joint shield portion, including the plurality of pin portions, are formed as a single unitary component by an additive layer manufacturing process.
2. 2 . The gimbal of claim 1 , wherein one or more of the core portion, the pipe engaging portions, the at least one flexible portion, and the at least one joint shield portion is cylindrical in cross-section.
3. 3 . The gimbal of claim 1 , wherein the joint cover portions are equally spaced around the core portion.
4. 4 . The gimbal of claim 1 , wherein the core portion further comprises at least one core portion joint guard that provides protective cover for the at least one flexible portion.
5. 5 . The gimbal of claim 4 , wherein the at least one core portion joint guard is configured to complement the configuration of a respective one of the joint cover portions to maximise protective cover for the at least one flexible portion.
6. 6 . The gimbal of claim 1 , wherein the at least one joint shield portion and the plurality of joint cover portions are configured to complement each other in order to maximise protective shielding for the at least one flexible portion of the gimbal.
7. 7 . The gimbal of claim 1 , wherein the gimbal has two to six of the joint cover portions and a single one of the joint shield portion.
8. 8 . The gimbal of claim 1 , wherein the gimbal has four of the joint cover portions, a single one of the joint shield portion, and the core portion has two of the pipe engaging portions and a single one of the at least one flexible portion.
9. 9 . The gimbal of claim 8 , wherein at least one of the pipe engaging portions is elongated.
10. 10 . The gimbal of claim 8 , wherein at least one of the pipe engaging portions is curved.
11. 11 . The gimbal of claim 1 , wherein the gimbal has four of the joint cover portions, a single one of the joint shield portion, and the core portion has three of the pipe engaging portions and a single one of the at least one flexible portion.
12. 12 . The gimbal of claim 11 , wherein at least one of the pipe engaging portions is elongated.
13. 13 . The gimbal of claim 11 , wherein at least one of the pipe engaging portions is curved.
14. 14 . The gimbal of claim 1 , wherein the gimbal has six to twelve of the joint cover portions, three of the joint shield portion, and the core portion has three of the pipe engaging portions and three of the flexible portion.
15. 15 . The gimbal of claim 1 , wherein the gimbal has at least one compartment containing vibration stress dampening material.
16. 16 . The gimbal of claim 1 , wherein each of the joint cover portions has an aperture that receives a pin portion that extends inwardly from the joint shield portion so each of the joint cover portions is pivotable with respect to the joint shield portion.
17. 17 . The gimbal of claim 1 , wherein the pin portion extends integrally from an internal surface of the at least one joint shield portion to interlock each of the joint cover portions with the at least one joint shield portion.
18. 18 . The gimbal of claim 1 , wherein the gimbal is a one-piece gimbal.
19. 19 . The gimbal of claim 1 , wherein the core portion and the at least one joint shield portion are formed from a material selected from at least one of titanium, a titanium alloy, steel, a steel alloy, aluminium, an aluminium alloy, a nickel-based superalloy, and combinations thereof.
20. 20 . The gimbal of claim 1 , wherein each of the plurality of pin portions interlocks with the respective one of the plurality of joint cover portions by extending through an aperture that is formed in the respective one of the plurality of joint cover portions.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This specification is based upon and claims the benefit of priority from United Kingdom patent application number GB 1918607.1 filed on Dec. 17, 2019, the entire contents of which is incorporated herein by reference. BACKGROUND Field of the Disclosure The present disclosure relates to gimbals and a method of manufacturing gimbals. The gimbals may be used for example on gas turbine aircraft engines. Description of the Related Art A gimbal is a 3-dimensional connecting two ducts/pipes that allows for angular movements between the connected ducts/pipes by providing two orthogonal axes of rotation. Gimbals are often used, for example, to provide flexible connections in between certain parts of the ducting which are often long running and are installed between certain parts of a gas turbine aircraft engine. Having a flexible connection reduces the stresses that result from the duct's ends moving during engine manoeuvres and to reduce thermal stresses in the ducting during engine operation. FIG. 1 shows known gimbals located on the fan case of a gas turbine aircraft engine. It is not uncommon for a gas turbine aircraft engine to have 10 to 15 gimbals. FIG. 2 shows an exploded view of the known gimbal shown in FIG. 1. Each gimbal consists of 12 sub-components. The gimbals are manufactured using traditional extrusion, rolling and forming processes which require a number of welds to connect various pins, devises, bellows and flanges. Welding requires the services of skilled welders and yet components that fail in service often fail as a result of one or more welds used to manufacture the component failing. The method of manufacturing the gimbal of FIGS. 1 and 2 restricts the size, design and strength of the gimbal that is manufactured. The gimbal design does not have sufficient strength to contain pressurised liquids therefore currently, its use is limited to connecting ducts that carry air. There is therefore a need to provide a gimbal that overcomes or at least minimises the disadvantages and limitations of the aforementioned known gimbal or at least provides a useful alternative to that and other known gimbals. SUMMARY OF THE DISCLOSURE According to a first aspect there is provided a gimbal for connecting pipes, the gimbal comprises a core portion and at least one joint shield portion that surrounds the core portion; the core portion, which has a core portion internal surface and a core portion external surface, comprises and at least two pipe engaging portions that are separated by at least one flexible portion, which has a flexible portion internal surface and a flexible portion external surface, and a plurality of joint cover portions; each joint cover portion extends from the core portion external surface of the core portion to provide a protective cover for the flexible portion external surface of at least one flexible portion of the core portion and is pivotably connected to a least one joint shield portion; the or each joint shield portion is configured to provide a protective shield for at least one flexible portion of the core portion; and the core portion and the or each joint shield portion are formed as a single unitary component. The gimbal may be used for connecting pipes or ducts of the gas turbine engine. Benefits include reducing part count, avoiding the need for any welding, improving gimbal strength, providing a gimbal that is suitable for carrying fluids generally, and potentially providing a “fit-and-forget” component. In some embodiments, the core portion and the or each joint shield portion are formed as a single unitary component by an additive layer manufacturing process. Additive layer manufacturing provides flexibility in the design, sizing and optimisation of gimbals for specific uses and applications. In some embodiments, one or more of the core portion, the pipe engaging portions, the or each flexible portion, and the or each joint shield portion is cylindrical in cross-section. Such portions being cylindrical, be that generally cylindrical or substantially cylindrical, provides structural strength, e.g. by balancing stresses, and is especially compatible with ducts and piping that are also cylindrical in cross-section. In some embodiments, the gimbal has two or more joint cover portions that are equally spaced around the core portion of the gimbal. Such arrangements assist in providing structural strength to the gimbal. In some embodiments, the core portion further comprises at least one core portion joint guard that provides protective cover for at least one flexible portion. Such arrangements optimise protective cover for the or each flexible portion. In some embodiments, the core portion joint guard is configured to complement the configuration of the joint cover portion to maximise protective cover for at least one flexible portion of the gimbal. Such arrangements optimise protective cover for the flexible portion(s) and help to optimise t