Abstract: A piston ring (10) for forming a seal between a piston (26) and piston housing (28). The piston ring (10) has first and second orthogonal axes (12, 14) and a body portion (18) which is resiliently deformable in the direction of the first axis (12) and is substantially rigid in the direction of the second axis (14).

Abstract: A hydraulic pump (6) comprising: a housing (20) having first and second inlets (100a, 100b) and first and second outlets (102a, 102b); a crankshaft (4) extending within the housing (20) and having axially offset first and second cams (62, 64); first and second groups (30, 32) of piston cylinder assemblies provided in the housing (20), each of the said groups (30, 32) having a plurality of piston cylinder assemblies having a working chamber of cyclically varying volume and being in driving relationship with the crankshaft (4); one or more electronically controllable valves (40) associated with the first and second groups (30, 32); and a controller (70) configured to actively control the opening and/or closing of the said electronically controllable valves (40) on each cycle of working chamber volume to thereby control the net displacement of fluid by the first and second groups (30, 32), wherein at least the first group (30) comprises a first piston cylinder assembly in driving relationship with the first cam

Abstract: A method of operating a hydraulic apparatus comprising a hydraulic circuit region and hydraulic machine which is controlled to displace pulses of fluid of known volume into or out of the hydraulic circuit region, generating pulses of pressure in the hydraulic circuit region and torque in the hydraulic machine shaft. The response of parts of the hydraulic apparatus to these pulses is measured and used to determine properties of the hydraulic apparatus. The response of the pressure in the hydraulic circuit region to pulses at different pressures can be used to measure the hydraulic stiffness of parts of the hydraulic circuit region. It is possible to detect faults and to make measurements useful in subsequent operation of the hydraulic apparatus.

Abstract: The invention provides a fluid working machine comprising: a cylinder block (1) having an axial bore (4); a crankshaft (2) which extends within the axial bore (4) and is rotatable about an axis of rotation (3); and first and second valve cylinder devices (13) provided in the cylinder block (1) arranged about and extending outwards with respect to the axial bore (4), the first and second valve cylinder devices (13) being axially offset from each other, the first and second valve cylinder devices (13) being offset from each other about the axis of rotation (3), and the first valve cylinder device having an axial extent which overlaps the axial extent of the second valve cylinder device, wherein the first and second valve cylinder devices (13) comprise first valves (14) having respective first working fluid ports (48, 49), the said respective first working fluid ports (48, 49) of the first valves (14) of the first and second valve cylinder devices (13) being in fluid communication with each other via a common co

Abstract: The invention provides a fluid working machine comprising: a crankshaft (2) which is rotatable about an axis of rotation (3); adjacent first and second groups (5, 6, 8, 10) of valve cylinder devices (13) spaced from each other about the axis of rotation (3), one or each of the first and second groups (5, 6, 8, 10) of valve cylinder devices having first, second and third valve cylinder devices (13) arranged about and extending outwards with respect to the crankshaft (2), the first and third valve cylinder devices being axially offset from each other, the second valve cylinder device being axially offset from the first and third valve cylinder devices and the second valve cylinder device being offset from the first and third valve cylinder devices about the axis of rotation, wherein the second valve cylinder device has an axial extent which overlaps with the axial extent of one, or the axial extents of both, of the first and third valve cylinder devices.

Abstract: The invention provides a fluid working machine comprising: a crankshaft (2) which is rotatable about an axis of rotation (3); adjacent first and second groups (5, 6, 8, 10) of valve cylinder devices (13) spaced from each other about the axis of rotation (3), one or each of the first and second groups (5, 6, 8, 10) of valve cylinder devices having first, second and third valve cylinder devices (13) arranged about and extending outwards with respect to the crankshaft (2), the first and third valve cylinder devices being axially offset from each other, the second valve cylinder device being axially offset from the first and third valve cylinder devices and the second valve cylinder device being offset from the first and third valve cylinder devices about the axis of rotation, wherein the second valve cylinder device has an axial extent which overlaps with the axial extent of one, or the axial extents of both, of the first and third valve cylinder devices.

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: An injection molding system, water jet cutting machine or other industrial system has a synthetically controlled variable displacement fluid working machine which outputs hydraulic fluid to one or more fluid consumers, such as rams or hydraulic motors, through hydraulically stiff fluid retaining volumes and receives hydraulic fluid back from one or more fluid consumers through the same or other said hydraulically stiff fluid retaining volumes. Individual piston cylinder assemblies can be allocated to different outputs. There may be no valve between the machine and the consumers. A working chamber of the machine can be caused to undergo a motoring cycle to enable the machine to output more power than is received from a motor driving the machine. An accumulator can be used to provide a source of hydraulic compliance. The machine can be controlled using pressure control, flow control, feed forward control or variable power/variable power limit control.

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 method of operating a hydraulic apparatus comprising a hydraulic circuit region and hydraulic machine which is controlled to displace pulses of fluid of known volume into or out of the hydraulic circuit region, generating pulses of pressure in the hydraulic circuit region and torque in the hydraulic machine shaft. The response of parts of the hydraulic apparatus to these pulses is measured and used to determine properties of the hydraulic apparatus. The response of the pressure in the hydraulic circuit region to pulses at different pressures can be used to measure the hydraulic stiffness of parts of the hydraulic circuit region. It is possible to detect faults and to make measurements useful in subsequent operation of the hydraulic apparatus.

Abstract: A hydraulic pump (6) comprising: a housing (20) having first and second inlets (100a, 100b) and first and second outlets (102a, 102b); a crankshaft (4) extending within the housing (20) and having axially offset first and second cams (62, 64); first and second groups (30, 32) of piston cylinder assemblies provided in the housing (20), each of the said groups (30, 32) having a plurality of piston cylinder assemblies having a working chamber of cyclically varying volume and being in driving relationship with the crankshaft (4); one or more electronically controllable valves (40) associated with the first and second groups (30, 32); and a controller (70) configured to actively control the opening and/or closing of the said electronically controllable valves (40) on each cycle of working chamber volume to thereby control the net displacement of fluid by the first and second groups (30, 32), wherein at least the first group (30) comprises a first piston cylinder assembly in driving relationship with the first cam

Abstract: A fluid-working machine has a working chamber of cyclically varying volume, high and low pressure manifolds, and high and low pressure valves for regulating the flow of fluid between the working chamber and the high and low pressure manifolds respectively. A controller actively controls at least one said valve to determine the net displacement of working fluid of the working chamber on a cycle by cycle basis. At least one said valve is a variable timing valve and the controller causes the valve to open or close at a time determined taking into account one or more properties of the performance of the fluid working machine measured during an earlier cycle of working chamber volume.

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: An injection moulding system, water jet cutting machine or other industrial system has a synthetically controlled variable displacement fluid working machine which outputs hydraulic fluid to one or more fluid consumers, such as rams or hydraulic motors, through hydraulically stiff fluid retaining volumes and receives hydraulic fluid back from one or more fluid consumers through the same or other said hydraulically stiff fluid retaining volumes. Individual piston cylinder assemblies can be allocated to different outputs. There may be no valve between the machine and the consumers. A working chamber of the machine can be caused to undergo a motoring cycle to enable the machine to output more power than is received from a motor driving the machine. An accumulator can be used to provide a source of hydraulic compliance. The machine can be controlled using pressure control, flow control, feed forward control or variable power/variable power limit control.

Abstract: The invention provides a fluid working machine comprising: a crankshaft (2) which is rotatable about an axis of rotation (3); adjacent first and second groups (5, 6, 8, 10) of valve cylinder devices (13) spaced from each other about the axis of rotation (3), one or each of the first and second groups (5, 6, 8, 10) of valve cylinder devices having first, second and third valve cylinder devices (13) arranged about and extending outwards with respect to the crankshaft (2), the first and third valve cylinder devices being axially offset from each other, the second valve cylinder device being axially offset from the first and third valve cylinder devices and the second valve cylinder device being offset from the first and third valve cylinder devices about the axis of rotation, wherein the second valve cylinder device has an axial extent which overlaps with the axial extent of one, or the axial extents of both, of the first and third valve cylinder devices.

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: The invention provides a fluid working machine comprising: a cylinder block (1) having an axial bore (4); a crankshaft (2) which extends within the axial bore (4) and is rotatable about an axis of rotation (3); and first and second valve cylinder devices (13) provided in the cylinder block (1) arranged about and extending outwards with respect to the axial bore (4), the first and second valve cylinder devices (13) being axially offset from each other, the first and second valve cylinder devices (13) being offset from each other about the axis of rotation (3), and the first valve cylinder device having an axial extent which overlaps the axial extent of the second valve cylinder device, wherein the first and second valve cylinder devices (13) comprise first valves (14) having respective first working fluid ports (48, 49), the said respective first working fluid ports (48, 49) of the first valves (14) of the first and second valve cylinder devices (13) being in fluid communication with each other via a common co

Abstract: A fluid-working machine for a renewable energy generation device, the fluid-working machine comprising a ring cam and a plurality of working chambers, the ring cam having an annular working surface extending around an axis of rotation of the ring cam, the annular working surface defining a plurality of waves, each working chamber having a piston, each piston in operative engagement with the ring cam working surface, the ring cam and working chambers being mounted to rotate relative to each other, cycles of working chamber volume being thereby coupled to rotation of the ring cam relative to the working chambers, characterized in that the individual waves of the ring cam working surface have an asymmetric profile.

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: Disclosed are antibody fusion proteins with a modified FcRn binding site and nucleic acid molecules encoding them. The antibody fusion protein include two polypeptide chains, wherein the first polypeptide chain includes a biologically active molecule linked to at least a portion of an immunoglobulin constant region. The second polypeptide chain includes at least a portion of an immunoglobulin constant region. One of the polypeptide chains includes a mutation in the FcRn binding site that reduces binding to FcRn. Also disclosed are methods of producing the fusion proteins and methods of using the fusion proteins for treating diseases and conditions alleviated by the administration of the fusion proteins.