Abstract: The present disclosure relates to a nozzle assembly for use in a servo valve. The nozzle assembly comprises three nozzle parts and a housing. The second part is coaxial with the first part and surrounds at least a first portion of the first part. The third part is coaxial with the first part, and a first portion of the third nozzle part surrounds a first portion of the second nozzle part, and a second portion of the third part is attached to a second portion of the first part. First and second nozzle parts are made of materials having approximately the same first coefficient of thermal expansion (TE1), and third part and housing are made of materials having approximately the same second coefficient of thermal expansion (TE2). TE1 is different from TE2. The interaction between the portions due to the differences in TE1 and TE2 allow the nozzle assembly to compensate for temperature fluctuations during and operation whilst remaining firmly held in position.

Abstract: A nozzle with changeable press fit and a method for calibrating a nozzle is described. The nozzle may be used in a nozzle/flapper type servovalve. The method comprises the steps of providing a nozzle within a cylindrical body defining a cylindrical bore, the nozzle having a tubular shape with an outer cylindrical surface and an inner radial surface., the method further comprises the steps of positioning a first, tubular locking member within the nozzle, and axially moving the first, tubular locking member within the nozzle. The first tubular locking member is configured to cause the nozzle to become positionally fixed at a selected position within the bore in response to the first, tubular locking member being axially moved relative to the nozzle. A nozzle positioning system is also described herein.

Abstract: The present disclosure relates to a nozzle assembly for a servo valve. The nozzle assembly comprises a nozzle including a nozzle inlet and a nozzle outlet, and a tubular filter mounted to the nozzle for filtering fluid flowing into the nozzle through the nozzle inlet.

Abstract: A servo valve for an actuator is described. The servo valve comprises a housing and a sleeve provided within the housing having a plurality of metering holes for communication with a cavity within. The servo valve further comprising a metering rod provided with metering members on a central rod for metering flow into and out of the cavity through the metering holes. The metering members comprise annular elements which are located axially on the central rod by an interference fit. The position of the metering members can be adjusted through using heat to thermally expand the metering member relative to the central rod to release the hold of the friction fit, allowing the metering member to be repositioned by being slid along the central rod.

Abstract: A nozzle of or for a servo valve comprises a nozzle element having a fluid outlet at a first axial end and a tubular body extending from the first end to an opposed, second axial end. The nozzle further comprises a plug element mounted in and closing the second axial end of the tubular body, thereby defining an internal cavity within the tubular body. One or more openings are formed through the tubular body to fluidly communicate with the internal cavity. A filter may be mounted across the internal cavity at a position axially intermediate the openings and the fluid outlet.

Abstract: A nozzle with changeable press fit and a method for calibrating a nozzle is described. The nozzle may be used in a nozzle/flapper type servovalve. The method comprises the steps of providing a nozzle within a cylindrical body defining a cylindrical bore, the nozzle having a tubular shape with an outer cylindrical surface and an inner radial surface, the method further comprises the steps of positioning a first, tubular locking member within the nozzle, and axially moving the first, tubular locking member within the nozzle. The first tubular locking member is configured to cause the nozzle to become positionally fixed at a selected position within the bore in response to the first, tubular locking member being axially moved relative to the nozzle. A nozzle positioning system is also described herein.

Abstract: There is provided a method of manufacturing a torsion spring, comprising providing a section of sheet metal, and forming the torsion spring from the section of sheet metal.

Abstract: The present disclosure relates to a servovalve assembly comprising a pair of opposed nozzles spaced apart by a first gap. A control element positioned in the first gap (G) between the pair of opposed nozzles. Each nozzle has an outlet opening. The control element has a central control portion and two resiliently deformable end portions at opposite ends of the central control portion. The central control portion is perpendicular to a central axis (C) of each nozzle outlet opening. The control element is configured such that the two resiliently deformable end portions elastically deform when the control element is placed under tension by a force applied parallel to the central control portion, so as to move the control element in a direction parallel to the central axis (C) of each nozzle outlet opening.

Abstract: An apparatus is provided which comprises: a first circuitry to receive a measurement of a first temperature of a section of a computing device during a first loading condition of the computing device, and to receive a measurement of a second temperature of the section of the computing device during a second loading condition of the computing device; and a second circuitry to detect a potential fault in a cooling system to cool the computing device, based at least in part on the first temperature and the second temperature.

Abstract: The present disclosure provides a heat exchanger system for a servovalve, comprising a base comprising a supply port in fluid communication with a return port, a first passage for fluid connection to a source of cooling fluid, and a second passage in fluid communication with the return port. The system further comprises one or more pipes located over a surface of the base, the one or more pipes fluidly connected between the first passage and the second passage, such that in use cooling fluid may flow from the first passage to the second passage via the network of pipes.

Abstract: The disclosure provides a method of securing a feedback spring relative to a spool of a servovalve, the method comprising inserting the feedback spring at least partially into an internal cavity of the spool, inserting two fixing members into the internal cavity such that they each oppose a portion of the feedback spring, bringing the fixing members into respective set positions, such that the fixing members clamp the feedback spring and prevent relative movement between the feedback spring and the spool, and securing the fixing members in their respective set positions, such that the fixing members remain in their clamping positions and prevent relative movement between the feedback spring and the spool.

Abstract: An assembly for use in a servovalve is provided. The assembly includes: a moveable member having a first end and a second end, the moveable member extending along a longitudinal axis (A?-A?) from the first end to the second end; and a torsion bridge, the torsion bridge extending around the moveable member at the first end thereof, and being adapted to rotate about a rotation axis (Ar), wherein the rotation axis (Ar) extends perpendicular to the longitudinal axis (A?-A?), and wherein the moveable member and the torsion bridge form an integral part having a planar surface adapted to receive a planar surface of an armature.

Abstract: A valve assembly includes a valve housing having a bore formed therein. The bore has an axis A and comprises a circumferentially extending groove formed at an end portion. An axially outer wall of the groove includes at least two circumferentially spaced radially inwardly extending retaining elements defining an axial slot therebetween. An end cap is received in the end portion of the bore and closes the end of the bore. The end cap includes a retaining portion that includes at least one radially outwardly extending retaining element which is shaped to be insertable through the axial slot into the groove and rotatable therein to a retaining position in which the radially outwardly extending retaining element aligns with one of the radially inwardly extending retaining elements to prevent axial withdrawal of the end cap from the bore.

Abstract: A valve body for a servovalve is provided, the valve body comprising: a first surface; a second surface offset from the first surface; a first passage extending through the body between the first and second surfaces from a first side of the body to a second side thereof; a second passage extending from the first surface towards the second surface and intersecting the first passage; a supply port joined with the first passage; a control port joined with the first passage; a return port joined with the first passage, wherein the return port comprises a third passage extending through the body between the first and second surfaces from a third side of the body to a fourth side thereof and intersecting with the first passage.

Abstract: A torque motor for a servovalve is provided, the torque motor comprising an armature and a first pole piece. The first pole piece has a first portion and a second portion that is selectively moveable relative to the first portion such that a size of an air gap formed between the second portion and the armature is adjusted in response to the movement of the second portion relative to the first portion.

Abstract: A method of manufacturing a hydraulic plug includes providing a shell comprising a circumferential wall, a sealed end, an open end and a cylindrical cavity opening to the open end is provided. The open end of the shell is wider externally than the sealed end. A head of an expander is inserted into the cavity. The head of the expander has a convex contact surface which is rounded in an axial direction (A) of the cavity. A region of the shell adjacent its open end is plastically deformed causing material from the circumferential wall of the shell to be displaced radially inward around the head of the expander to form a constricted opening retaining the expander within the cavity. The deforming reshapes an internal surface of the cavity from a cylindrical to a non-linear shaped ramp leading up to a constricted opening.

Abstract: A torque motor for use in a servovalve wherein only two holes must be provided through each of the pole pieces in order to assemble the torque motor together. The torque motor comprises first and second opposing pole pieces, first and second permanent magnets positioned between the first and second pole pieces; an armature comprising a magnetic plate and a flapper, the magnetic plate being positioned between the first and second permanent magnets, the flapper being connected at one end to the magnetic plate; and further comprising: first and second fastening means each extending through the first pole piece, the armature and the second pole piece to thereby fasten the torque motor together.

Abstract: The present disclosure relates to a nozzle assembly for a servo valve. The nozzle assembly comprises a nozzle including a nozzle inlet and a nozzle outlet, and a tubular filter mounted to the nozzle for filtering fluid flowing into the nozzle through the nozzle inlet.

Abstract: A new method of forming a torsion spring for use in a servovalve is described. The method comprises individually forming the different components of the torsion spring and then connecting the individual components together using a brazing process. The torsion spring created by this method is also described.

Abstract: A hydraulic valve is disclosed comprising a venting passage for allowing fluidic communication between an interior and an exterior of the hydraulic valve, the venting passage having a first portion following a first path extending in a first plane, and a second portion following a second path extending in a second plane, wherein the first plane is at an angle to the second plane, and wherein the first and/or second path is a labyrinth path in its respective plane.