EP-4737774-A1 - VALVE APPARATUS

EP4737774A1EP 4737774 A1EP4737774 A1EP 4737774A1EP-4737774-A1

Abstract

The present invention relates to a valve apparatus for a fluid delivery system comprising a valve housing having a fluid flow path, a valve member, a valve actuator operably connected to the valve member and configured to move the valve member between first and second positions, and a thermally-activated locking mechanism which provides the valve apparatus with an additional passive safety feature which will automatically lock and inhibit movement of the valve member upon reaching a pre-determined activation temperature.

Inventors

Elms, Martin
Khakhar, Satish

Assignees

Airbus Operations Limited

Dates

Publication Date: 20260506
Application Date: 20250818

Claims (15)

A valve apparatus for a fluid delivery system comprising: a valve housing having an inlet and an outlet which together form a fluid flow path across the valve housing; a valve member configured to move between a first position in which fluid is able to flow along the fluid flow path, and a second position in which the flow of fluid along the fluid flow path is restricted; a valve actuator operably connected to the valve member, said valve actuator being configured to move the valve member between the first and second positions; and a thermally-activated locking mechanism in thermal communication with the inlet and configured to inhibit movement of the valve member upon reaching a temperature above or below a pre-determined activation temperature.
The valve apparatus according to claim 1, wherein the thermally-activated locking mechanism is configured to inhibit movement of the valve member upon reaching a temperature below the pre-determined activation temperature.
The valve apparatus according to claim 2, wherein the thermally-activated locking mechanism is configured to inhibit movement of the valve member upon reaching a temperature below -60°c, optionally below -80°c, and more below -100°c.
The valve apparatus according to any preceding claim, wherein the valve actuator is a manually-operated valve actuator.
The valve apparatus according to any preceding claim, wherein the valve apparatus further comprises at least one groove formed in the valve member or formed in a drive shaft connected to said valve member, and wherein the thermally-activated locking mechanism comprises: a locking pin configured to move between a first position in which the locking pin engages with the at least one groove, and a second position in which the locking pin does not engage with the at least one groove; and a thermally-activated actuator configured to move the locking pin into the first position upon reaching a temperature above or below the pre-determined activation temperature.
The valve apparatus according to claim 5, wherein the thermally-activated actuator comprises a shape-memory alloy.
The valve apparatus according to claim 5, wherein the thermally-activated actuator comprises a bi-metallic strip comprising at least two materials having different coefficients of thermal expansion.
The valve apparatus according to any of claims 5 to 7, wherein the valve comprises a pair of grooves formed in the valve member or formed in a drive shaft connected to said valve member, wherein the first of said grooves is positioned so as to align with the locking pin when the valve member is in the first position, and wherein the second of said grooves is positioned so as to align with the locking pin when the valve member is in the second position.
The valve apparatus according to claim 8, wherein the pair of grooves are spaced apart by an angle of approximately 90 degrees about a rotational axis of the valve member.
The valve apparatus according to any of claims 5 to 9, wherein the valve apparatus further comprises a biasing member configured to bias the locking pin into the first position.
The valve apparatus according to any of claims 5 to 10, wherein the valve apparatus further comprises a manually-operated release mechanism for moving the locking pin from the first position to the second position.
The valve apparatus according to any of claims 5 to 11, wherein the valve apparatus further comprises a heat transfer conduit having a first end in thermal communication with the inlet and a second end in thermal communication with the thermally-activated locking mechanism.
The valve apparatus according to claim 1, wherein the thermally-activated locking mechanism is configured to inhibit movement of the valve member upon reaching a temperature above the pre-determined activation temperature, and optionally upon reaching a temperature above 100°c.
An aircraft fuel delivery system comprising: a fuel tank for storing cryogenic fuel; at least one fluid conduit for transferring cryogenic fuel from the fuel tank to one or more aircraft engines; and at least one valve apparatus according to any of the preceding claims, wherein the valve member of said valve apparatus is positioned along the at least one fluid conduit.
An aircraft comprising the aircraft fuel delivery system according to claim 14.

Description

FIELD OF THE INVENTION The present invention relates to a valve apparatus for a fluid delivery system, an aircraft fuel delivery system comprising said valve apparatus, and to an aircraft comprising said aircraft fuel delivery system. BACKGROUND OF THE INVENTION Cryogenic fuels such a liquified hydrogen and liquified natural gas are a promising technology for improving efficiency and sustainability in various applications, such as aerospace, transportation, and power generation. Notably, cryogenic fuels have a very high energy density, which means they can provide more power per unit of mass, as well as a low carbon content, which means they produce less greenhouse gas when burned. Cryogenic fuels can also be produced from renewable sources, such as water or biomass, and therefore the use of such fuels reduces dependence on fossil fuels. However, one of the drawbacks associated with cryogenic fuels is that in order to maximize their volumetric energy density, they must be stored in liquid form. In order to do this, cryogenic fuels must be kept at extremely low temperatures (e.g., between - 150°c and -255°c). As such, the use of cryogenic fuels introduces a new safety factor (when compared to more conventional fuels) which must be accounted for to prevent maintenance personnel from coming into unwanted physical contact with such cryogenic fuels during routine maintenance operations. It is an aim of the present invention to provide a solution to this issue. SUMMARY OF THE INVENTION A first aspect of the invention provides a valve apparatus for a fluid delivery system comprising: a valve housing having an inlet and an outlet which together form a fluid flow path across the valve housing;a valve member configured to move between a first position in which fluid is able to flow along the fluid flow path, and a second position in which the flow of fluid along the fluid flow path is restricted;a valve actuator operably connected to the valve member, said valve actuator being configured to move the valve member between the first and second positions; anda thermally-activated locking mechanism in thermal communication with the inlet and configured to inhibit movement of the valve member upon reaching a temperature above or below a pre-determined activation temperature. Advantageously, the provision of a thermally-activated locking mechanism which is configured to inhibit movement of the valve member upon reaching a pre-determined activation temperature provides the valve apparatus with an additional passive safety feature which will automatically lock the valve member (without user input) when the pre-determined activation temperature has been reached. This helps to prevent the inadvertent release of potentially hazardous fluids (e.g., cryogenic aircraft fuel) due to inadvertent actuation of the valve member during routine maintenance operations. It shall also be appreciated that since the thermally-activated locking mechanism does not feature any complex electrical systems, it does not significantly impact the cost, reliability and/or maintenance burden of the valve. In exemplary embodiments, the valve apparatus may be a shut-off valve. In exemplary embodiments, the thermally-activated locking mechanism may be configured to inhibit movement of the valve member upon reaching a temperature below the pre-determined activation temperature. Advantageously, the provision of a thermally-activated locking mechanism which is configured to inhibit movement of the valve member upon reaching a temperature below the pre-determined activation temperature enables the locking mechanism to operate effectively when used with cryogenic fluids (such as cryogenic aircraft fuel). In exemplary embodiments, the thermally-activated locking mechanism may be configured to inhibit movement of the valve member upon reaching a temperature below -60°c. In exemplary embodiments, the thermally-activated locking mechanism may be configured to inhibit movement of the valve member upon reaching a temperature below -80°c. In exemplary embodiments, the thermally-activated locking mechanism may be configured to inhibit movement of the valve member upon reaching a temperature below -100°c. In exemplary embodiments, the valve apparatus may further comprise at least one groove formed in the valve member or formed in a drive shaft connected to said valve member. In exemplary embodiments, the thermally-activated locking mechanism may further comprise: a locking pin configured to move between a first (e.g., extended) position in which the locking pin engages with the at least one groove formed in the valve member or formed in a drive shaft connected to said valve member, and a second (e.g., retracted) position in which the locking pin does not engage with the at least one groove; anda thermally-activated actuator configured to move the locking pin into the first (e.g., extended) position upon reaching a temperature above or below the pre-determined activation