Abstract: A control valve arrangement includes a valve body with a filling chamber with a filling hole. A filling valve is arranged in the filling chamber for opening or closing a first fluid communication controlling filling of a first control chamber, the filling valve having a filling valve member with a moving valve seat, the filling valve member being normally biased open by a first spring. A control valve opens and closes a second fluid communication for controlling the emptying of the first control chamber, the control valve being normally biased closed by a second spring. A plug is arranged in the valve body for closing the filling chamber, the plug being provided with an opening which cooperates with the moving valve seat, the opening defining the first fluid communication between the filling chamber and the first control chamber.

Abstract: A control valve arrangement includes a valve body with a filling chamber with a filling hole. A filling valve is arranged in the filling chamber for opening or closing a first fluid communication controlling filling of a first control chamber, the filling valve having a filling valve member with a moving valve seat, the filling valve member being normally biased open by a first spring. A control valve opens and closes a second fluid communication for controlling the emptying of the first control chamber, the control valve being normally biased closed by a second spring. A plug is arranged in the valve body for closing the filling chamber, the plug being provided with an opening which cooperates with the moving valve seat, the opening defining the first fluid communication between the filling chamber and the first control chamber.

Abstract: An injection device for administering a reagent into an exhaust passage of an internal combustion engine, the injection device having an axis along its length and comprising an outwardly opening valve member having a seating surface which is engageable with a valve seating region. A seating member provided with an internal bore which defines the valve seating region, wherein the internal bore further defines a flow re-directing region downstream of the valve seating region. The seating member has an end face provided with a feature which intersects with at least a portion of the flow re-directing region to define, together with the flow re-directing region, a spray path for reagent exiting the injection device when the valve member is moved outwardly from the bore away from the valve seating region. The spray path has a variable spray angle, relative to the axis, around the circumference of the valve seating region.

Abstract: A pumping assembly is provided which is suitable for use in a variety of dosing pumps. The pumping assembly comprises a pump body with a pump bore, and a sleeve fixed within the pump bore. The sleeve has a first end, a second end and a sleeve bore. A plunger is adapted to enter the first end of the sleeve and to reciprocate within the sleeve bore. The sleeve has at least one port to allow fluid flow through a wall of the sleeve. The, or each, port is elongated in a direction substantially orthogonal to a direction of reciprocation.

Abstract: A pump assembly having improved cooling for use in a selective catalytic reduction system is disclosed. The pump assembly comprises a pump housing having a body portion and a nozzle portion extending from the body portion, a jacket including a cavity for receiving the pump housing, first and second ports for cooling fluid, and a flow guide disposed between the jacket and the pump housing. The cavity includes a first compartment for cooling fluid defined in part by the flow guide and in part by the pump housing and being in fluid communication with the first port; and a second compartment for cooling fluid defined in part by the flow guide and in part by the jacket. The first compartment is in fluid communication with the second port by way of the second compartment.

Abstract: An injection device for administering a reagent into an exhaust passage of an internal combustion engine, the injection device having an axis along its length and comprising an outwardly opening valve member having a seating surface which is engageable with a valve seating region. A seating member provided with an internal bore which defines the valve seating region, wherein the internal bore further defines a flow re-directing region downstream of the valve seating region. The seating member has an end face provided with a feature which intersects with at least a portion of the flow re-directing region to define, together with the flow re-directing region, a spray path for reagent exiting the injection device when the valve member is moved outwardly from the bore away from the valve seating region. The spray path has a variable spray angle, relative to the axis, around the circumference of the valve seating region.

Abstract: An injection device for administering a reagent into an exhaust passage of an internal combustion engine, the injection device having an axis along its length and comprising an outwardly opening valve member having a seating surface which is engageable with a valve seating region. A seating member provided with an internal bore which defines the valve seating region, wherein the internal bore further defines a flow re-directing region downstream of the valve seating region. The seating member has an end face provided with a feature which intersects with at least a portion of the flow re-directing region to define, together with the flow re-directing region, a spray path for reagent exiting the injection device when the valve member is moved outwardly from the bore away from the valve seating region. The spray path has a variable spray angle, relative to the axis, around the circumference of the valve seating region.

Abstract: An injection nozzle for injecting fuel into a combustion chamber of an internal combustion engine comprises a nozzle body having a bore for receiving fuel from a supply line for pressurized fuel, an outlet from the bore for delivering fuel to the combustion chamber, in use, and a valve needle defining a needle axis and being slidable within the bore. The needle comprises a needle guide portion arranged to guide the needle within the bore. The injection nozzle further comprises a restriction within the bore for restricting fuel flow through the bore, and a restrictive element moveable with the needle and located upstream of the needle guide portion. At least a part of a downstream side of the restrictive element comprises a bevelled surface that extends to a peripheral edge of the restrictive element, the bevelled surface being non-perpendicular to the needle axis.

Abstract: A mounting arrangement for attaching a pump arrangement to an exhaust pipe at a boss includes a delivery nozzle section and a remaining section including a pump body. The mounting arrangement includes a packing for supporting the pump body at the remaining section of the pump arrangement.

Abstract: A fuel injector includes a nozzle body with a nozzle bore, a first valve needle received within the nozzle bore and being engageable with a first seat region to control fuel delivery through a first set of nozzle outlets, and a second valve needle received within a valve bore provided in the first valve needle and being engageable with a second seat region arranged to control fuel delivery through a second set of nozzle outlets. A control chamber for fuel is provided between the first valve needle and the second valve needle, wherein movement of the first valve needle is responsive to fuel pressure in the control chamber, and wherein movement of the second valve needle is mechanically coupled to an armature of the first actuator arrangement. A second actuator arrangement controls movement of the first valve needle by controlling fuel flow into the control chamber.

Abstract: An injection nozzle for injecting fuel into a combustion chamber of an internal combustion engine comprises a nozzle body having a bore for receiving fuel from a supply line for pressurised fuel, an outlet from the bore for delivering fuel to the combustion chamber, in use, and a valve needle defining a needle axis and being slidable within the bore. The needle comprises a needle guide portion arranged to guide the needle within the bore. The injection nozzle further comprises a restriction within the bore for restricting fuel flow through the bore, and a restrictive element moveable with the needle and located upstream of the needle guide portion. At least a part of a downstream side of the restrictive element comprises a bevelled surface that extends to a peripheral edge of the restrictive element, the bevelled surface being non-perpendicular to the needle axis.

Abstract: A pump assembly having improved cooling for use in a selective catalytic reduction system is disclosed. The pump assembly comprises a pump housing having a body portion and a nozzle portion extending from the body portion, a jacket including a cavity for receiving the pump housing, first and second ports for cooling fluid, and a flow guide disposed between the jacket and the pump housing. The cavity includes a first compartment for cooling fluid defined in part by the flow guide and in part by the pump housing and being in fluid communication with the first port; and a second compartment for cooling fluid defined in part by the flow guide and in part by the jacket. The first compartment is in fluid communication with the second port by way of the second compartment.

Abstract: An armature for a solenoid actuator is disclosed. The armature comprises a first face comprising a recess suitable for receiving a biasing spring in use of the armature; a second face opposite the first face; and fluid communication passages for providing a fluid flow path through the armature between the recess and the second face in use of the armature. The first face is uninterrupted by the fluid communication passages. The invention reduces the risk of cavitation damage during operation of the actuator. In one application, the actuator is used in a fluid pump for a selective catalytic reduction system.

Abstract: A pump for pumping a fluid comprises an inlet, an outlet, an internal volume disposed between the inlet and the outlet, a first pumping arrangement operable to pump a first volume of fluid from the inlet into the internal volume, and a second pumping arrangement operable to pump a second volume of fluid from the internal volume into the outlet. In a first mode of operation of the pump, the first volume of fluid is greater than the second volume of fluid such that, in use, the pressure of the fluid within the internal volume is elevated to a level above the pressure of the fluid at the inlet.

Abstract: An injection device for administering a reagent into an exhaust passage of an internal combustion engine, the injection device having an axis along its length and comprising an outwardly opening valve member having a seating surface which is engageable with a valve seating region. A seating member provided with an internal bore which defines the valve seating region, wherein the internal bore further defines a flow re-directing region downstream of the valve seating region. The seating member has an end face provided with a feature which intersects with at least a portion of the flow re-directing region to define, together with the flow re-directing region, a spray path for reagent exiting the injection device when the valve member is moved outwardly from the bore away from the valve seating region. The spray path has a variable spray angle, relative to the axis, around the circumference of the valve seating region.

Abstract: A method of operating a fuel injector having a piezoelectric actuator for controlling movement of an injector valve needle comprises: (a) prior to an initial fuel injection event, reducing the voltage across the actuator at an initial rate so as to de-energize the actuator; (b) increasing the voltage across the actuator at a first rate in order to initiate an initial fuel injection event of a first fuel injection sequence; and (c) reducing the voltage across the actuator at a second rate in order to terminate the initial fuel injection event. The method may further comprise the step of: (d) increasing the voltage across the actuator at a third rate, which is lower than the first rate, so as to de-energize the actuator but without initiating an injection event, once the initial fuel injection event has terminated and before a subsequent fuel injection event is initiated.

Abstract: A fuel injector comprising an injector body, a capnut, and a pressure sensor exposed to pressure changes in a combustion chamber in use, wherein the pressure sensor is accommodated within the capnut. Optionally, the fuel injector further comprises a signal cable external to the injector body to connect with the pressure sensor.

Abstract: A piezoelectric actuator comprises a co-fired stack of piezoelectric elements formed from a piezoelectric material and a plurality of positive internal electrodes interdigitated with a plurality of negative internal electrodes throughout the stack to define active regions of the piezoelectric material which are responsive to a voltage applied across the internal electrodes, in use. An external positive electrode connects with the positive internal electrodes and an external negative electrode connects with the negative internal electrodes. The actuator is characterized in that the stack further comprises means for deliberately creating artificial cracks within the stack at a location at which the artificial cracks do not give rise to a short circuit between the internal electrodes but serve to relieve stresses within the piezoelectric material.

Abstract: An injection device for administering a reagent into an exhaust chamber of an internal combustion engine, comprising a device inlet and a device outlet and a sub-assembly held securely within a device housing. The sub-assembly comprises (i) valve housing defining a valve seat, (ii) valve means movable outwardly from the valve housing, away from the valve seat, to permit the reagent to be delivered into the exhaust chamber through the device outlet, whereby a force is applied to the valve means due to reagent delivered to the device inlet which serves to urge the valve means away from the valve seat, and (iii) bias means for applying a biasing force to the valve means which serves to urge the valve means against the valve seat so as to prevent delivery of the reagent through the device outlet into the exhaust chamber.

Abstract: A piezoelectric actuator for use in a diesel engine. The actuator comprises a piezoelectric element which is encapsulated such that a layer of gas at a pressure above atmospheric pressure surrounds the piezoelectric element. The presence of the gas within the encapsulation around the element avoids the need to passivate electrodes exposed on the surface of the element.