Abstract: A valve assembly is provided, the valve assembly comprising a body that defines a fluid flow path between an inlet and an outlet with a frangible member between the inlet and the outlet across the fluid flow path so as to block fluid flow The valve assembly also includes a member for rupturing the frangible member, a spring biasing the rupturing member into contact with the frangible member and a member for retaining the rupturing member away from the frangible member. A magnet is spaced apart from the retaining member, and a non-magnetic sleeve is disposed between the magnet and the retaining member. The non-magnetic sleeve blocks a magnetic field provided by the magnet. Also included is a trigger for removing the non-magnetic sleeve, wherein, when the non-magnetic sleeve is removed, in use, the magnetic field attracts the retaining member to release the rupturing member to cause rupture of the frangible member.

Abstract: A servovalve includes a fluid transfer valve assembly comprising a supply port and a control port, a moveable valve spool arranged to regulate flow of fluid from the supply port to the control port in response to a control signal, and a drive assembly configured to axially move the valve spool relative to the fluid transfer assembly in response to the control signal to regulate the fluid flow. The drive assembly includes a steerable member moveable by an amount determined by the control signal to cause corresponding movement of the valve spool. The drive assembly further includes piezoelectric actuator means configured to move said steerable member in response to the control signal.

Abstract: A flapper element for a check valve comprises at least one mounting lug configured to receive a shaft for rotation relative thereto and having a row of teeth for engaging complementary teeth on a mounting lug of a similar flapper element. The complementary teeth tie the rotation of the two flapper elements.