Abstract: A valve assembly for regulating the flow of fluid between a working chamber of a fluid-working machine and a fluid manifold. The valve assembly comprising a valve body comprising a valve seat, a fluid passage extending through the valve body, and a travelling member comprising a valve member and operable between an open position in which the valve member is spaced apart from the valve seat and fluid can flow through the fluid passage and a closed position in which the valve member is in sealing contact with the valve seat preventing fluid from flowing through the fluid passage. The valve assembly further defines a fluid flow path passing in a first fluid flow mode, between the valve member and the valve seat, and into the fluid passage. The valve assembly is characterised by a barrier upstream of the valve member, to the barrier reduces one or more forces which would otherwise act on the valve member as a result of the flow of fluid to urge the valve member towards the valve seat.

Abstract: A valve assembly suitable for regulating the flow of fluid between a working chamber of a fluid-working machine and a fluid manifold. The valve assembly comprises a valve body comprising a valve seat, a fluid passage extending through the valve body, and a travelling member comprising a valve member, which valve member is operable between an open position in which the valve member is spaced apart from the valve seat and fluid can flow through the fluid passage and a closed position in which the valve member is in sealing contact with the valve seat preventing fluid from flowing through the fluid passage. The valve assembly defining a fluid flow path passing, in a first fluid flow mode, between the valve member and the valve seat, and into the fluid passage.

Abstract: A communications system and method for transmitting digital information includes arranging a modulator to have an input bit stream of binary data and arranging a signal generator to generate four orthonormal hyper phase shift keying (HPSK) basis functions that are periodic functions with a duration T. A bit to symbol mapper is arranged to combine the bit stream and the HPSK basis functions to form a succession of 4-bit HPSK symbols for 16-HPSK, 5-bit HPSK symbols for 32-HPSK or 6-bit HPSK symbols for 64-HPSK, and a transmitter is arranged to transmit signals indicative of the HPSK symbols. A receiver is arranged to receive the signals from the transmitter and the HPSK symbols are demodulated with the HPSK basis functions to reproduce the bit stream of binary data.

Abstract: The invention relates to a valve actuator (2), comprising a magnetic core (6) with an interspace (8) and at least one bifurcating branch (7), at least one variable magnetic field generating device (16), at least one permanent magnetic field generating device (13) and at least one movable magnetic component (12), wherein the bifurcating branch (7) defines a first region (4) and a second region (5) of said magnetic core (6).

Abstract: A fluid working machine comprises a controller (12) and a working chamber (2) of cyclically varying volume. The working, chamber has both an electronically controllable primary low pressure valve (14) and a secondary low pressure port (22) associated therewith, each of which is openable and closable in phased relation to cycles of working chamber volume to bring the working chamber into fluid communication with a low pressure manifold (16, 26). At least the primary low pressure valve is under the active control of the controller to enable the controller to determine the net displacement of fluid by the working chamber on a cycle by cycle basis. The primary low pressure valve and the secondary low pressure port are openable concurrently during a portion of at least some cycles of working chamber volume to enable fluid to flow into or out of the working chamber concurrently through both the primary low pressure valve and the secondary low pressure port.

Abstract: A fluid-working machine has a plurality of working chambers, e.g., cylinders, of cyclically changing volume, a high-pressure fluid manifold and a low-pressure fluid manifold, at least one valve linking each working chamber to each manifold, and electronic sequencing means for operating said valves in timed relationship with the changing volume of each chamber, wherein the electronic sequencing means is arranged to operate the valves of each chamber in one of an idling mode, a partial mode in which only part of the usable volume of the chamber is used, and a full mode in which all of the usable volume of the chamber is used, and the electronic sequencing means is arranged to select the mode of each chamber on successive cycles so as to infinitely vary the time averaged effective flow rate of fluid through the machine.

Abstract: A hydraulic machine has at least one working chamber (11) of cyclically changing volume, and low- and high-pressure valve means (15, 13) to control the connection of the or each chamber to low- and high-pressure lines (16, 14) respectively. A method of operating the machine includes holding the low-pressure valve means (15) closed during at least an entire cycle of the chamber (11), starting at minimum chamber volume, such that gas dissolved in liquid in the chamber is released therefrom during an expansion of the chamber volume and re-dissolved during a reduction thereof.

Abstract: A method and apparatus for monitoring link diversity between two communication networks are disclosed. Physical diversity of communication links are important to guarantee service availability and reliability. Diversity monitoring can be achieved by using routing information of the communication links.

Abstract: A fluid power system comprises a pump with multiple independently variable outlets (11, 12, 13, 14), each of which is capable of delivering fluid in individually controllable volume units and a plurality of hydraulic loads (15, 16, 18, 20). A system of switching valves is configured to create fluid connections between the pump outlets and the loads. A control system commands both the pump and the switching valves, so as to create valve state combinations to satisfy load conditions as demanded by an operator The number of pump outlets (11, 12, 13, 14) connected to one or more of the loads (15, 16, 18, 20) is changeable to satisfy the flow required of the load due to the operator demand, each pump outlet being commanded to produce a flow depending on the status of other outlets connected a load to which the outlet is connected and the operator demand for that load.

Abstract: The present invention provides a hydraulic pump for use in driving a load with a control modulation system which modulates a primary control signal in order to accommodate variations in secondary changeable parameters which require control at a higher frequency or have a lower latency.

Abstract: An electromagnetic actuator comprises a core (1), a ferromagnetic component (2) movable in a gap (5) in the core, and a magnet (4) for attracting the component to one side of the gap. A flux concentrator (12) concentrates the magnetic flux on that side of the gap (5) and a solenoid (8) produces magnetic flux in the gap. A magnetic circuit of the solenoid is defined by part of the core (1), part of the gap (5) and by a further gap (6) between the ferromagnetic component (2) and the core (1). A demagnetiser (7) has a magnetic circuit defined by another part of the core (1), another part of the gap (5) and by the further gap (6). The demagnetiser is arranged to demagnetise the magnet (4) at least to the extent that the magnetic flux produced by the solenoid (8) is diverted from the flux concentrator (12) into the further gap (6) and the movable component (2) is movable away from the magnet (4) under the magnetic force of the solenoid (8).

Abstract: A telephone network voting system is configured to process a large number of calls. The system receives telephone ballots cast by voters by dialing an 8YY telephone number. The telephone ballots are received by network edge switch (NES) from a local exchange carrier (LEC), and sequentially received calls are routed to a repeating sequence of segmentation databases (SDs). The SDs are configured for routing calls in a sequentially received series of 8YY calls to a repeating sequence of said NCPs. Switches are mapped to NCPs to minimize congestion on A and AA links. Call announcements are stored in disk cache.

Abstract: The present invention provides a method of controlling a fluid working machine (12) having a plurality of working cylinders (14) having pistons (16) therein and arranged to drive a shaft (18), in which said cylinders are supplied with pressurised working fluid via a manifold (24), the contents of which may be 5 purged by a de-pressuriser taking one of a number for forms such as to allow re-activation of said machine (10).

Abstract: The present invention provides a cooling system such as employed in cooling a heat source and a transmission system having said cooling system integrated therewith. The cooling system further includes a pump for supplying hydraulic fluid under pressure to a motor for driving a fan employed in the cooling process. In operation, a controller initiates operation of the pump such as to supply hydraulic fluid to said motor only when needed, thereby to improve the efficiency and controllability of the cooling system.

Abstract: A valvetrain control arrangement for an internal combustion engine. A fluid-working machine (1) has working chambers (3) of cyclically varying volume, each connected to a piston actuator (4) which is capable of moving an intake or exhaust valve in the internal combustion engine. The engine crankshaft (2) drives a crankshaft of the fluid-working machine at the same speed as the engine. Each working chamber (3) is linked to a low-pressure manifold (7) by a venting valve (6), the venting valve being normally open but electromagnetically closable by a signal from an electronic sequencing means (8) which operates in timed relationship to the engine crankshaft phase.

Abstract: A fluid-working machine comprises at least one primary working chamber such as a cylinder (4) of cyclically changing volume and primary valves (7) to control the connection of the at least one chamber to low (10)- and high (9)-pressure manifolds. The machine has at least one secondary working chamber (5) of cyclically changing volume and a secondary valve (12, 21) for placing the secondary chamber in communication with the primary chamber (4) in an active state of the secondary chamber (5) and for isolating it therefrom in an idling state of the secondary chamber.

Abstract: A surfboard having a hull, a multi-function fin and multi-function fin receiving box system. This invention incorporates the use of a variety of fins, fin bases including multi-tab, rectangular and positioning inserts. Receiving box and locator inserts are optionally configured so that the fin may be adjustable positioned and secured in a three-dimensional configuration. The fins positioning may include fore and aft, cant angel and angel of attack positioning. The fin positioning may be adjusted through recessed wedge or other shaped receiving voids and insert elements positioned in and around the structural wall areas of the receiving box. The interior wall surfaces of the fin-securing cavity accommodate the positioning of the fins base attachment and aligning structures and are constructed with various extended, receiving, positioning, supporting and securing features.

Abstract: A method of repairing a combustor dome with a swirler assembly having a first deflector component attached to a swirler having a first joint configuration includes: removing the first deflector component; machining a second joint configuration different from the first joint configuration in the swirler; providing a replacement deflector component having a shape complementary to the second joint configuration; and securing the replacement deflector component to the swirler

Abstract: A telephone network voting system is configured to process a large number of calls. The system receives telephone ballots cast by voters by dialing an 8YY telephone number. The telephone ballots are received by network edge switch (NES) from a local exchange carrier (LEC), and sequentially received calls are routed to a repeating sequence of segmentation databases (SDs). The SDs are configured for routing calls in a sequentially received series of 8YY calls to a repeating sequence of said NCPs. Switches are mapped to NCPs to minimize congestion on A and AA links. Call announcements are stored in disk cache.

Abstract: A zoom lens is disclosed having a zoom ratio larger than four with a field of view at the short focal length position larger than 85 degrees and with a minimal number of moving groups. The zoom lens utilizes a compound zoom structure comprising an NP or NPP zoom kernel followed by a P or PP zoom relay, with only two or three moving groups that can be used for both zooming, focusing and athermalization. An overall compact package size is achieved by the use of prisms to fold the optical path in strategic locations. An optional variable power liquid cell can provide close focusing with little or no focus breathing.