Abstract:
A serviceable filtration arrangement for use in an internal combustion engine of a vehicle to remove contaminants from a liquid to be filtered. The filtration arrangement (1, 101) comprises an upstream filtration element (7,107) and a downstream filtration element (5,105). Upon servicing of the vehicle the upstream filtration element (7,107) can be replaced independently of the downstream filtration element (5,105). The upstream filtration element (7,107) has a filtration media (61) which has characteristics that have been selected such that the upstream filtration element (7,107) becomes clogged before a filtration media (51) of the downstream filtration element (5,105) becomes clogged.
Abstract:
A fuel injector offering improved accuracy of fuel delivery is described. The fuel injector comprises a supply means (24, 24a) for high pressure fuel, an injection nozzle (25) including a valve needle (26), a control chamber (42) for the valve needle, a first filling flow path (44) providing flow from the supply means (24) into the control chamber (42), and a control valve (48) for controlling fuel pressure within the control chamber (42). The control valve (48) comprises a first valve chamber (104) and a second valve chamber (106), and a control valve member (60) operable between a first state in which the first valve chamber (104) communicates with the supply means (24), and in which flow between the second valve chamber (106) and a low-pressure drain (21) is prevented, and a second state in which flow between the first valve chamber (104) and the supply means (24) is prevented, and in which the second valve chamber (106) is in communication with the low-pressure drain (21). The fuel injector further comprises a drain flow path (50) including a drain restriction (50a) and permitting flow from the control chamber (42) to the second valve chamber (106) when the control valve member (60) is in the second state, and a second filling flow path (47) permitting flow from the first valve chamber (104) into the control chamber (42) when the control valve member (60) is in the first state, wherein the second filling flow path (47) bypasses the drain restriction (50a). The drain restriction (50a) comprises an orifice.
Abstract:
A method of assessing the functioning of an EGR cooler of an EGR system in an internal combustion engine, wherein the EGR cooler can be selectively operated in a first and a second operating condition; and wherein the engine comprises at least one cylinder equipped with a pressure sensor. The assessment of the functioning of the EGR cooler is based on the variation of a combustion characteristic value depending on cylinder pressure (CA50), upon switching of the EGR cooler from a first to a second operating condition.
Abstract:
Plug assembly (44) for high-pressure valve (10) of the type with a tubular body extending along a longitudinal axis (A) and in which, under the action of a piloted actuator, a needle (14) moves longitudinally (A) between a closed position and an open position, the plug assembly (44) comprising a plug (26) having a flat part (27) able to be fixed onto the body transversally to the longitudinal axis (A), and a spring (36) intended to apply to the needle (14) a force biasing it axially towards the closed position. The spring (36) is fixed to the plug (26) forming with it an integrated assembly (44).
Abstract:
An electrical drive arrangement of a fuel injection system comprising a power supply (22) operatively connected to an injector driver stage (24) which, in turn, is operatively connected to at least one fuel injector (35). The electrical drive arrangement includes a voltage regulation device (26) operatively connected between the power supply (22) and the injector driver stage (24), wherein the voltage regulation device (26) is arranged to regulate the voltage supply from the power supply (22) to the injector driver stage (24).
Abstract:
An electrical drive arrangement for at least one fuel injector (54) of a fuel injection system comprises: a buffer capacitor (60) adapted to store energy; a charging stage (64) for charging said buffer capacitor (60) to a target charge voltage (V charge ); and an injector driver stage (52) operatively connected to a fuel injector (54). A voltage regulation device (62) is operatively connected between the buffer capacitor (60) and the injector driver stage (52) and configured to supply an operating voltage to the driver stage. A controller (82) is configured to determine said target charge voltage (V charge ) for the buffer capacitor (60) depending on pre-set conditions, while the charging stage (64) is adapted to receive from the controller an input representative of the target charge voltage.
Abstract:
A valve assembly for controlling the rate of flow of fluid between a valve inlet (18) and a valve outlet (22) comprises a valve housing (10), and a spool valve member (14) that is movable axially within a valve bore (12) provided in the valve housing (10) in an opening direction and a closing direction. The spool valve member (14) is provided with a blind bore (28), the open end of which communicates with the valve outlet, and at least one opening (32, 34; 40; 50, 52, 54, 56) into the blind bore, the at least one opening communicating, to a variable degree dependent on the axial position of the spool valve member (14) within the valve bore (12), with the valve inlet (18). The valve inlet (18) comprises a first boundary (24) and a second boundary (26), wherein the first boundary (24) acts as a control edge so that for axial positions of the spool valve member (14) in which the opening (30, 32; 40; 50, 52, 54, 56) does not overlap the control edge there is no flow into the outlet (22). A blind end (30) of the blind bore (28) is positioned, for all positions of the spool valve member (14) within the valve bore (12), beyond the second boundary (26) in the opening direction of the spool valve member (14).
Abstract:
A method of manufacturing a metal housing (14) includes providing a first passage (10) through the metal housing (14) and providing a second passage (12) through the metal housing (14), wherein the second passage (12) includes a region of intersection (20) which intersects the first passage (10) to define an opening (22, 122, 222) into the first passage (10). The method further includes subjecting the metal housing (14) to a heat treatment process to carburise an internal surface of the first and/or second passage (10, 12) and, subsequent to the carburisation process, applying a hard stage electrochemical machining process to the carburised internal surface of the first and/or second passage (10, 12) to improve surface finish. Another aspect of the invention includes providing a second passage (12) through the metal housing (14) by means of a tool (46), such as an electrochemical machining electrode, having an active region without rotational symmetry about its axis (Y-Y). The active region is shaped to provide the region of intersection (20) with a generally conical taper (29, 31) to the opening (22; 122; 222).