The present disclosure provides a high-pressure fuel pump having barrel sets comprising offset, opposing barrel units within the same plane and having plungers disposed therein. The high-pressure fuel pump further includes a camshaft having at least one offset lobe and a cam ring encircling the lobe and in contact with the plungers, which translate the rotational movement of the camshaft to longitudinal movement of the plungers, controlling inflow, compression, and outflow of fuel within the pump.

A hydraulic apparatus comprises first and second manifolds each of which is connected to a plurality of actuators via corresponding actuator valves connected in parallel and operated responsive to inputs to regulate the flow of fluid to the actuators. A plurality of working chambers are connectable to either the first or second manifold and have a net flow which is controlled responsive to a negative feedback signal. The negative feedback signal is determined in response to a calculated pressure or flow rate in virtual fluid flow paths extending from the first and second manifolds.

A hydraulic apparatus has a plurality of pump modules each of which is formed by a plurality of working chambers having a common high pressure manifold. A connecting circuit switchably connects pump modules to first and second hydraulic circuit portions to allocate capacity as first and second demands for hydraulic fluid vary. In an apparatus which may have two or more connecting circuit outputs, valves may be controlled or working chamber pumping cycles made inactive to facilitate the reallocation of a pump module from one output to another, and a control strategy addresses pump module allocation when the demands for hydraulic fluid exceed available capacity.

A prime mover and a plurality of hydraulic actuators, a hydraulic machine having a rotatable shaft in driven engagement with the prime mover and comprising working chambers, a hydraulic circuit between working chambers of the hydraulic machine and the hydraulic actuators, each working chamber of the hydraulic machine comprising a low-pressure and high-pressure valves regulating the flow of hydraulic fluid between the working chamber and a corresponding low-pressure manifold and a high-pressure manifold. The hydraulic machine being configured to actively control the low-pressure valves of the working chambers to select the net displacement of hydraulic fluid by each working chamber on each cycle of working chamber volume, and thereby the net displacement of hydraulic fluid by the working chambers, responsive to a demand signal, wherein the apparatus further comprises a controller configured to calculate the demand signal in response to a measured property of the hydraulic circuit or actuators.

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 (62) and a second piston cylinder assembly in driving relationship with the second cam (64), and wherein the first group is configured to receive working fluid from the first inlet (100a) and to output working fluid to the first outlet (102a) and the second group is configured to receive working fluid from the second inlet (100b) and to output working fluid to the second outlet (102b).

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 (62) and a second piston cylinder assembly in driving relationship with the second cam (64), and wherein the first group is configured to receive working fluid from the first inlet (100a) and to output working fluid to the first outlet (102a) and the second group is configured to receive working fluid from the second inlet (100b) and to output working fluid to the second outlet (102b).

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 (62) and a second piston cylinder assembly in driving relationship with the second cam (64), and wherein the first group is configured to receive working fluid from the first inlet (100a) and to output working fluid to the first outlet (102a) and the second group is configured to receive working fluid from the second inlet (100b) and to output working fluid to the second outlet (102b).

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 conduit (50, 52) extending within the cylinder block (1).

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 conduit (50, 52) extending within the cylinder block (1).

A method includes determining a rotational position of a crankshaft in a multiplex pump from one or more sensors disposed on the crankshaft, determining a position of each of a plurality of pistons along a corresponding pump bore in relation to a total stroke length of each piston and a connecting rod length, calculating an individual theoretical displaced volume of fluid for each of the pump bores in the multiplex pump based on the rotational position of the crankshaft, and summing the individual theoretical displaced volumes to determine a total theoretical pumped volume by the multiplex pump. A calibration method includes determination of the multiplex pump efficiency versus speed and discharge pressure, and the effect of pump leakage and valve closing delay on the pump efficiency. Verification of the pump performance and efficiency may be controlled during pumping to insure the validity of the last calibration data set.