Valve

A valve comprising a first part defining a first aperture and a second part defining a second aperture, the first part being moveable relative to the second part between a closed configuration in which passage of a fluid through the valve is substantially prevented and an open configuration in which passage of fluid is allowed;

• wherein the first part comprises a flexible plate-like member configured to engage a sealing face of the second part when in the closed configuration and lock in the closed configuration in response to a pressure differential across the valve.

A valve comprising a first part defining a first aperture and a second part defining a second aperture, the first part being moveable relative to the second part between a closed configuration in which passage of a fluid through the valve is substantially prevented and an open configuration in which passage of fluid is allowed;

• wherein the first part is constrained to move substantially parallel to a surface defined by the sealing face of the second part by a retaining plate.

A valve comprising a first part defining first array of apertures and a second part defining a second array of apertures, the first part being moveable laterally relative to the second part between a closed configuration in which the first and second arrays of apertures are not registered and passage of a fluid through the valve is substantially prevented and an open configuration in which the first and second arrays of apertures are registered and passage of fluid is allowed;

• wherein the first part comprises a pair of moveable plates, each plate of the pair comprising a sub-set of the first array of apertures.

A valve comprising a first part defining a first aperture and a second part defining a second aperture, the first part being moveable relative to the second part between a closed configuration in which passage of a fluid through the valve is substantially prevented and an open configuration in which passage of fluid is allowed;

• wherein the valve further comprises a locking part to maintain the first and second parts in the closed configuration.

A valve comprising a first part defining a first array of apertures and a second part defining a second array of apertures, the first part being moveable relative to the second part between a closed configuration in which the first and second arrays of apertures are not registered and passage of a fluid through the valve is substantially prevented and an open configuration in which the first and second arrays of apertures are registered and passage of fluid is allowed;

• wherein the first and second parts each have an aperture density greater than 1000 per m2.

A valve comprising a first part defining a first aperture and a second part defining a second aperture, the first part being moveable relative to the second part between a closed configuration in which passage of a fluid through the valve is substantially prevented and an open configuration in which passage of fluid is allowed;

• wherein the valve has a mass of less than 20 kg per m2.