Abstract: A dampening stop pin that reduces a needle velocity at the time when the needle valve of a fuel injector is about to be seated in a closed position. A gap between a bottom surface of the stop-pin flange and a sealing seat of a nozzle is provided to compress the fuel trapped therein to form a fuel cushion that dampens the closing motion of the needle. Moreover, a diametrical clearance between an outer circumferential edge of the flange and an inner surface of a needle spring cage must be sized to prevent undesired high pressure from building up in the gap by venting a quantity of compressed fuel while still permitting the fuel cushion to dampen the closing force of the needle.

Abstract: An oil activated fuel injector which provides a pilot quantity of fuel prior to the main fuel injection event. A control system for a fuel injector includes a sensor for providing a signal to a control which is indicative of an opening motion of a spool. The control initiates a pull back of the spool, upon receipt of the signal, to eliminate a bounce back phenomenon of the spool during an injection of a pilot quantity of fuel. The signal may be representative of a pressure of working fluid or fuel, as well as a position or acceleration of the spool.

Abstract: A multiple stage pump having valves downstream from each respective pump in a same line thereof. The respective lines then merge into a common line. The multiple stage pump prevents pressure variations and shot to shot fuel variations.

Abstract: A solenoid end cap assembly having a flat mating surface. The flat mating surface is a single planar mating surface and is designed to mate with a substantially flat mating surface of a valve control body. The solenoid, housed within the solenoid end cap, does not protrude past the flat surface and may form part of the substantially flat mating surface of the solenoid end cap. The flat mating surfaces of the valve control body and the solenoid end cap assembly eliminates the need for ring dowels in the assembly between the solenoid and the valve control body. This reduces manufacturing costs and assembly time. The flat mating surfaces also provide a uniform mounting surface for the solenoid from injector to injector. This increases performance characteristics, as well as increases thermal conductivity and magnetic conductivity characteristics.

Abstract: A control a control for an injector includes an energizing device actuated by a fluid pressure during an injection event to provide a monitoring voltage. The control unit is used with an injector and is capable of monitoring the variables of the injector such as opening and closing times of the spool valve by using a pressure of the working fluid. The control unit can control the opening and closing of the injector by determining the opening times based on a generated voltage.

Abstract: A temperature compensated actuator device comprises a piezoelectric stack having first and second ends along a central axis and having a first thermal expansion coefficient; and a compensator arranged on one end of the piezoelectric stack. The compensator comprises a first member in form of a cylinder; a second member in form of a piston plate wherein the first member and the second member are arranged movably along the axis with respect to each other and define a hollow space between them; and a compensation member having a thermal expansion coefficient higher than the first thermal expansion coefficient for filling the hollow space.

Abstract: A coupling device having a body portion is adapted to be mated with an end cap assembly of a fuel injector. The body portion has a connecting portion spanning between a first electrical connector and a second electrical connector at opposing ends thereof. A first set of conductive leads connects the first electrical connector to a first set of solenoid wires and a second set of conductive leads connects the second electrical connector to a second set of solenoid wires. The first set of conductive leads spans the connecting portion to connect the first electrical connector and the first set of solenoid wires. An end cap and coupling device as well as a fuel injector assembly using the coupling device is provided.

Abstract: A device and a method for positioning the ports and passages of injector parts during an assembly of a fuel injector. The device uses a groove or a keyway with a retaining band having a key portion disposed on the retaining band. The method includes forming grooves on the parts of the fuel injector to be aligned, preventing displacement of the parts by inserting the key portion of the retaining band into the substantially aligned groove.

Abstract: A multiple stage pump having valves downstream from each respective pump in a same line thereof. The respective lines then merge into a common line. The multiple stage pump prevents pressure variations. The multiple stage pump includes a first pump in a first stage and a second pump in a second stage. At least one valve is downstream from one of the first pump and the second pump in at least one of the first stage and the second stage. A common branch line connects the first stage and the second stage to a common hydraulic system.

Abstract: A fuel injector having a piezoelectric actuator. A needle valve is mounted in the injector body and has an opening hydraulic surface substantially surrounded by a high-pressure fuel line in fluid communication with a high-pressure fuel chamber. A control piston partly defines a piston control chamber, which is in fluid communication with the opening hydraulic surface and the high-pressure fuel chamber. The piezoelectric actuator is activated between an off position and an on position for positioning a control valve into an open position or a closed position. A high-pressure fuel condition is maintained in the piston control chamber by fuel supplied from the high-pressure fuel chamber and independent of any actuation of the control valve. In a low pressure fuel condition, a force on the opening hydraulic surface of the needle valve member is greater than the downward force on the closing hydraulic surface thereby opening the needle valve member for producing an injection event.

Abstract: An oil activated fuel injector which provides a pilot quantity of fuel prior to the main fuel injection event. The oil activated fuel injector includes a delay piston assembly in fluid communication with a high pressure chamber of the fuel injector. The pilot quantity of fuel flows through the delay piston during a pre stroke of the plunger. The oil activated fuel injector reduces engine emissions and noise, and eliminates the need for additional working fluid to be provided therein in order to provide a pilot quantity of fuel.

Abstract: An oil activated fuel injector which provides a pilot quantity of fuel prior to the main fuel injection event. The oil activated fuel injector includes a throttle which provides fluid communication between the high pressure chamber and a fuel bore which leads to the nozzle of the oil activated fuel injector. The pilot quantity of fuel flows through the throttle and into the fuel bore during a pre stroke of the plunger. The oil activated fuel injector reduces engine emissions and noise, and eliminates the need for additional working fluid to be provided therein in order to provide a pilot quantity of fuel.

Abstract: A multiple stage pump having valves upstream from each respective pump in a same line thereof. The respective lines then merge into a common line. The multiple stage pump prevents pressure variations. The multiple stage pump includes a first pump in a first stage and a second pump in a second stage. At least one valve is upstream from one of the first pump and the second pump in at least one of the first stage and the second stage. A common branch line connects the first stage and the second stage to a common hydraulic system.

Abstract: A fuel injector device having a blowback valve disposed in the injector body, the blowback valve having a first portion and a second portion, a fuel passage being disposed through the first and second portions, a closure member being disposed in the fuel passage and movable in a first direction and a second direction, the closure member permitting a predetermined volume of fuel flow in the second direction before the closure member moves to the second position. The invention also include a method to control the fuel flow through an injector by providing a body having a first portion and a second portion, a fuel passage extending through the portions and a closure member movable in the fuel passage between a first position and a second position, and the closure member permitting a predetermined volume of fuel to flow in one direction before the closure member moves to the second position.

Abstract: An oil activated fuel injector control valve which reduces bouncing of the spool and an impact of the spool on an open coil. This eliminates shot by shot variations in the fuel injector as well as increasing the efficiency of the fuel injector. The fuel injector includes a valve control body which has a vent holes which prevent air from mixing with the working fluid. In this manner, the working fluid does not have to compress and/or dissolve the air in the working ports prior to acting on the piston and plunger mechanism in an intensifier body of the fuel injector.

Abstract: A method is provided for matching dimensions of a spool to a control valve body of a fuel injector. The method includes the steps of measuring land locations and an overall length of a first component of the fuel injector and measuring land locations of a second component of the fuel injector relative to at least each other. The method also includes calculating a grinding amount to be removed from the second component based on the following criteria (i) the measured land locations and the overall length of the first component and (ii) the measured land locations of the second component relative to each other.

Abstract: A control valve for a fuel injector generally includes a valve body and a spool positioned within a bore of said valve body. The spool is slideable between a first and second position. The control valve also comprises a first bore in fluid communication with a rail inlet of the fuel injector, a cross bore positioned within the valve body and offset from the first bore, and a groove located about the spool. The groove provides fluid communication between the cross bore and the first bore when the spool is in the first position, and seals fluid communication when the spool is in the second position. At least two solenoids are provided on opposing sides of the spool for moving the spool between the first and second positions, and a non-magnetic barrier is provided between the solenoids and the spool.

Abstract: An oil activated fuel injector control valve which substantially eliminates captured air within working fluid of the fuel injector. This eliminates shot by shot variations in the fuel injector as well as increasing the efficiency of the fuel injector. The fuel injector includes a control valve body which has vent holes which prevent air from mixing with the working fluid. In this manner, the working fluid does not have to compress and/or dissolve the air in the working ports prior to acting on the piston and plunger mechanism in an intensifier body of the fuel injector.

Abstract: A rail connection assembly includes an outer rail connection tube having a rail connection outlet, a component having a substantially centrally located bore that is fixed to the outer rail connection tube remote from said rail connection outlet, and a piston adapted for movement between a first position and a second position, with the second position being remote from said bore. A nipple having a predetermined cross section and extends from the piston and is slidably movable into and remote from said bore when the piston is moved between the first and second positions, respectively. A fluid communication path exists between the bore and the rail connection outlet. This provides a pilot injection of fuel when the piston moves into an intermediate position between the first and second positions and a full injection of fuel when the piston reaches the second position.

Abstract: A wire guide includes a body having an opening adapted to conform to a shape of a control valve body of a fuel injector. A first channel is provided on a first side of the body and an extension extends from a second, opposing side of the body. A second channel is formed on the extension. At least one clip is formed on a periphery of the body between the first channel and the second channel. At least two projections may inwardly extend from a wall which defines the opening. And, rounded protuberances may extend from an underside of the body at opposing sides thereof.