Abstract:
A method of controlling a drive circuit (20a, 20b, 20c) for an injector arrangement including at least one injector (12; 12a, 12b) having capacitive-like properties, the drive circuit including at least one inductor (L1; L11; L21; L22) and a bidirectional current path (26) coupled to the at least one injector; selector means (Q13, Q14, Q23, Q24) for selecting one of the at least one injector(s) (12; 12a, 12b); and switching means for controlling current flow through the at least one injector (12; 12a, 12b) and the at least one inductor (L1; L11; L21; L22) to open and close the at least one injector, wherein the switching means includes a discharge switch means controllable to cause a charging current (I CHARGE ) to flow through the bidirectional current path (26) during a charge mode so as to charge the at least one injector, and discharge switch means (Q2; Q12; Q22) to cause a discharge current (I DISCHARGE ) to flow through the bidirectional current path (26) during a discharge mode so as to discharge the at least one injector. The method comprises selecting an injector (12; 12a, 12b) to permit a discharging current to be supplied thereto so as to initiate an injection event; activating the discharge switch means (Q2; Q12; Q22) to supply the discharging current to the selected injector until the voltage across the selected injector reaches a predetermined discharge level (V discharge ); and enabling the discharge switch means (Q2; Q12; Q22) for a time period (t1) after the predetermined discharge level (V discharge ) has been reached thereby reducing voltage ringing in the drive circuit.
Abstract:
A filter assembly (1) comprising a disposable filter body (2) and a central support (3) for the disposable filter body (2). Openings (14, 16) are provided in upper and lower ends (6, 8) of the disposable filter body (2) for receiving a respective end of the central support (3). The filter assembly (1) further comprising a disposable filter cartridge (4), housed within the disposable filter body (2), and housing a filter member (30) for filtering particulate contaminates from a flow of fluid through the filter assembly (1). The filter member (30) is hollow and the disposable filter cartridge (4) further comprises an impermeable wall (32) that extends axially through the filter member (30). The central support (3) is separable from the disposable filter body (2) and removable from the openings (14, 16) to allow disposal and replacement of the filter body (2) and the filter cartridge (4) during servicing. The central support (3) may include a series of integral heating elements (49) which serve to provide a heating effect to the fluid flow, prior to passage through the filter member (30).
Abstract:
A method of controlling combustion in an internal combustion engine with exhaust after treatment device is proposed, wherein upon detection of a request for a regeneration event of the exhaust after treatment device, a regeneration combustion mode comprising a pilot injection and a retarded main injection is operated. During the regeneration combustion mode the injection timing of the main injection is controlled so that its retard is not later than a retard threshold that is determined as the maximum timing retard to provide the desired torque, but with an injected fuel quantity not exceeding a maximum fuel quantity given by a stored smoke-limit map.
Abstract:
There is presented a method for monitoring an oxidation catalyst in an exhaust line of an internal combustion engine, wherein a catalyst diagnostic event comprises a test cycle during which a conversion capability of the oxidation catalyst is determined based on the exotherm generated by post-injection of fuel. The diagnostic event may only be initiated when the temperature of the oxidation catalyst lies within a predetermined temperature range.
Abstract:
A method of poling a ferroelectric sample (2a) suitable for use in a fuel injector (5) of an internal combustion engine, the method comprising providing a ferroelectric sample (2a) having a stack of ferroelectric layers (4), wherein adjacent layers (4) are separated by internal electrodes (6a, 6b), forming a first group (6a) and a second group (6b) of electrodes; applying a multiaxial pressure to the ferroelectric sample; reducing the bonding strength between each pair of adjacent ferroelectric layers and internal electrodes; and generating a first electric field between the first (6a) and second (6b) group of electrodes to pole each ferroelectric layer (4) in a first poling direction.
Abstract:
A method of controlling a vehicle engine system is described. The method involves sensing a pressure in the engine; generating a signal (24, 124) indicative of the sensed pressure; encrypting the signal to generate an encrypted data message (30, 130) containing information indicative of the sensed pressure; transmitting the encrypted data message to an engine control means (12, 112); decrypting the encrypted data message to obtain the information indicative of the sensed pressure; and controlling the vehicle engine system in dependence upon the information contained in the encrypted data message. A pressure sensor (10, 110) for use in the method, and a suitably programmed electronic control unit are also described.
Abstract:
A mounting arrangement (28) for attaching a pump (10) to an exhaust pipe (12), the mounting arrangement comprising a boss (30) attached or attachable to the exhaust pipe (12), and retaining means (34, 46, 48) for retaining the pump in the boss (30), in use, characterised in that the retaining means comprise means (46, 48) for damping vibration of the pump (10). Preferably, the retaining means further comprise means (46, 48) for reducing heat transfer from the exhaust pipe (12) to the pump (10).