Abstract: A servovalve includes a fluid transfer valve assembly comprising a primary fluid supply port and a control port, a moveable valve spool arranged to regulate flow of fluid through a first fluid pathway from the primary fluid supply port to the control port, and a jet pipe assembly configured to axially move the spool relative to the fluid transfer valve assembly in response to a control signal to regulate the fluid flow along the first fluid pathway. The jet pipe assembly comprises a steerable nozzle from which fluid is directed to the ends of the spool in an amount determined by the control signal. The spool comprises an opening and an interior passage fluidly coupling the opening to the jet pipe assembly via a second fluid pathway. The first fluid pathway is fluidly isolated from the second fluid pathway within the spool.

Abstract: An integral flapper and nozzle structure for a servo valve assembly whereby the flapper, orifices and nozzles are formed by sheets of metal formed into a single component.

Abstract: An integral flapper and nozzle structure for a servo valve assembly whereby the flapper, orifices and nozzles are formed by sheets of metal formed into a single component.

Abstract: An integral flapper and nozzle structure for a servo valve assembly whereby the flapper, orifices and nozzles are formed by sheets of metal formed into a single component.

Abstract: A filter assembly includes a manifold having a fluid inlet and a fluid outlet, a filter housing having a filter medium provided therein, the filter medium defining an inner filter chamber and defining an outer filter chamber between the filter medium and the filter housing, the filter housing being removably attached to the manifold. The filter assembly includes a valve assembly mounted inside the manifold, and a by-pass channel defined inside the manifold between the fluid inlet and the fluid outlet. The valve assembly includes a valve body, a by-pass valve system, and a shut off valve system. The by-pass valve system includes a by-pass valve piston having a piston body, and a by-pass valve spring arranged to move the by-pass valve piston. The shut off valve system includes a shut off valve piston, and a shut off valve spring arranged to move the shut off valve piston.

Abstract: A valve is provided, the valve including a housing; and a valve element, the housing comprising a cylindrical bore defining an axial direction and an annular shoulder extending into the cylindrical bore, wherein the valve element is axially moveable within the cylindrical bore so as to move the valve element between a closed position in which the valve element engages with the annular shoulder and an open position in which the valve element is spaced from the annular shoulder, wherein, in the open position, fluid flowing into the valve in a first axial direction may flow through one or more apertures provided in the valve element and through the valve, wherein the valve element and the annular shoulder are configured to be in continuous contact along an annular contact surface when in the closed position so as to seal against fluid flow through the valve.

Abstract: A filter assembly includes a manifold having a fluid inlet and a fluid outlet, a filter housing having a filter medium provided therein, the filter medium defining an inner filter chamber and defining an outer filter chamber between the filter medium and the filter housing, the filter housing being removably attached to the manifold. The filter assembly includes a valve assembly mounted inside the manifold, and a by-pass channel defined inside the manifold between the fluid inlet and the fluid outlet. The valve assembly includes a valve body, a by-pass valve system, and a shut off valve system. The by-pass valve system includes a by-pass valve piston having a piston body, and a by-pass valve spring arranged to move the by-pass valve piston. The shut off valve system includes a shut off valve piston, and a shut off valve spring arranged to move the shut off valve piston.

Abstract: An integral flapper and nozzle structure for a servo valve assembly whereby the flapper, orifices and nozzles are formed by sheets of metal formed into a single component.

Abstract: An electrical assembly comprises a wall having an opening, one or more electrical leads extending through the wall opening and a grommet arranged in the wall opening. The grommet comprises a body of resilient elastomeric material having at least one hole extending axially therethrough for receiving a respective individual electrical lead. The grommet body has a portion with an external diameter Db which, in an uncompressed state of the grommet is greater than the internal diameter (Dop) of the wall opening whereby when the grommet inserted in the wall opening, the grommet body is compressed into sealing and clamping engagement with the electrical lead.

Abstract: There is provided a method of assembling a torque motor. The method comprises fastening the torque motor to a support such that any magnetic elements of the torque motor are substantially fixed in position with respect to the support, but without securing an armature to the torque motor, locating the armature of the torque motor around a fixed element of the torque motor such that the armature is able to move with respect to the fixed element, moving the armature with respect to the fixed element whilst the magnetic elements of the torque motor are substantially fixed in position with respect to the support, so as to position the armature in an in use orientation or position, and then attaching the armature to the fixed element in the in use orientation or position.

Abstract: A torque motor for a servovalve, said torque motor comprising a set of pole pieces comprising a first pole piece and a second pole piece. An armature is also provided between the first pole piece and the second pole piece, said armature configured to provide air gaps (AG1-AG4) between the armature and the first pole piece, and the armature and the second pole piece. The armature is configured to rotate about a centre point (CP). The set of pole pieces is also adapted to rotate around the centre point (CP) such that the air gaps (AG1-AG4) can be adjusted.

Abstract: A linear variable differential transducer is disclosed comprising a tubular magnetic core formed from a sheet, a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the magnetic core.

Abstract: There is provided a pole-piece for a torque motor, the pole-piece comprising a first section formed separate from a second section, wherein the first section and the second section are configured to abut each other to form one or more lines of abutment on an outer surface thereof, and each line of abutment follows an S- or Z-shape when the first section abuts the second section.

Abstract: There is provided a pole-piece for a torque motor, the pole-piece comprising a first section formed separate from a second section, wherein the first section is held in position with respect to the second section using one or more rigid members.

Abstract: A servovalve comprising: 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 member configured to axially move the valve spool relative to the fluid transfer assembly in response to the control signal to regulate the fluid flow.

Abstract: A spool assembly for a second stage of a servo valve comprises a spool having an axis (L) and an opening for a feedback member provided in a central region of the spool extending perpendicular to the axis. An adjustable joint is provided within the spool for securing a feedback member relative to the spool, comprising first and second jaw arms being displaceable relative to each other along the axis of the spool. The jaw arms have opposing clamping surfaces, wherein the clamping surfaces are arranged to be drawn towards each other as the jaw arms are drawn away from each other, such that a feedback member can be clamped between the opposed clamping surfaces of the jaw arms and thereby secured relative to the spool.

Abstract: A directional control valve, comprising: a valve body having a bore to receive a spool; a spool mounted in said bore; at least one stopper mounted in said bore, said stopper being axially adjustable and fixable at a selected axial position. The provision of an axially adjustable stopper eliminates the need to select a suitably sized stopper from a selection of stoppers or to grind down (resize) a single stopper. It reduces the number of parts in the valve (thus reducing cost) and it also shortens the calibration time for the valve as there is no need to remove the stopper from inside the bore in order to perform an adjustment. As the valve is tested after each adjustment, this also means not removing the stopper and breaking the seal (draining the valve) between each testing phase. The calibration can therefore be performed much more efficiently.