Cummins Engine Company, Inc.

Cummins Intellectual Property, Inc.

Cummins Inc.

Gary L Gant

George L Muntean

Corydon Edward Morris

Harry L Wilson

Lester L Peters

David L Buchanan

Ernst Winklhofer

C Edward Morris, Jr

Heribert Kammerstetter

Bela Doszpoly

Jeffrey C Huang

David E Shultz

Kevin L Vogt

Denis Gill

Julius P Perr

David Paul Genter

John D Crofts

Edward D Smith

Leslie A Roettgen

Edward Benjamin Manring

Dennis A Wilber

Mark S Cavanagh

Daniel K Hickey

Jeffrey J Sullivan

David A Bolis

P Douglas Free

Mustahsen Gull

Charles R Kelso

O Eddie Sturman

Jeffrey C Osborn

Jeffery L Campbell

Kevin R Wadell

Donald E Duckworth

James R Katzenmeyer

Hisham K Mozaffar

John R Youngblood

Michael D Breeden

Brian W Robinson

James A Sting

Stephen L Gaal

Jon Padfield

Neville H Reiners

Michael H Shea

&Aacute;rp&aacute;d M Pataki

R Michael Harmon

A fuel injector is provided that includes various precise configuration parameters, including dimensions, shape and/or relative positioning of fuel injector features, resulting in improved efficiency of fuel flow through the fuel injector.

Fuel injector

A piezoelectric-actuated fuel injector for injecting fuel into a combustion chamber of an internal combustion engine is provided which includes a piezoelectric actuator movable to expand in a first direction and movable to contract in a second direction opposite the first direction, and a hydraulic link assembly disposed within said injector cavity. The hydraulic link assembly includes a hydraulic link barrel having an inner bore, a hydraulic link outer plunger positioned to slidably move in the inner bore, and a hydraulic link operatively connected to a needle valve to move the needle valve in the second direction toward the open position in response to movement of the piezoelectric actuator in the first direction. A hydraulic link inner plunger is attached to the needle valve and extends into a center bore of the hydraulic link outer plunger. Leakage control features and hydraulic link refill valves are also provided.

Piezoelectric direct acting fuel injector with hydraulic link

A fuel injector device, for injecting fuel into a combustion chamber of an internal combustion engine, has a nozzle valve and nozzle valve control assembly adapted to use a control valve and high pressure fuel in the fuel injector in order to actuate movement of the nozzle valve between an open position to inject fuel and a closed position to terminate fuel injection. The nozzle valve control assembly employs a pressure balancing control valve so that the fuel pressure exerts a zero net force on the control valve in a dimension along which the control valve moves. Thus, the actuation occurs independently of the fuel pressure. In addition, the actuator is operably connected to the control valve by at least a hydraulic linkage, where the hydraulic linkage compensates for changes in the actuator and the injector body due to changes in temperature.

Fuel injector with pressure balancing valve

A reprogrammable electronic step timing control system having a fuel pressure threshold that is discretely variable as a function of engine speed. The fuel pressure threshold is increased for engine speeds above rated speed by a predetermined amount. A programming key is provided in a wiring harness to allow fuel pressure and speed thresholds to be readily changed.

Reprogrammable electronic step timing control system for control of injection timing in a hydromechanical fuel supply system

A three-way fuel injection control valve assembly is provided which includes a pilot valve for controlling the movement of a drain valve member and a separate supply valve member to minimize valve response time and transition flow losses. The solenoid operated two-way pilot valve controls the flow of fuel from a control volume formed adjacent the ends of the drain valve member and the supply valve member to begin and end an injection event. A transition flow loss limiting feature is provided which causes the drain valve member to close prior to the opening of the supply valve member and subsequently causes the supply valve member to close prior to the opening of the drain valve member during a given injection event thereby minimizing transition flow losses. The transition flow loss limiting feature includes sizing the cross sectional areas of the supply valve member and the drain valve member, sizing a bias plunger for biasing the drain valve member and sizing one or more bias springs so that no opening overlap occurs between the supply valve member and the drain valve member.

Pilot valve controlled three-way fuel injection control valve assembly

A servo-controlled fuel injector is provided which includes a leakage limiting valve device for limiting the quantity of high pressure fuel available for leakage into the combustion chamber in the event the closed nozzle valve element fails to sealingly engage its seat between injection events. The servo-controlled fuel injector includes a control volume positioned adjacent an outer end of the nozzle valve element, a control volume charge circuit for supplying fuel to the control volume, a drain circuit for draining fuel from the control volume to a low pressure drain and an injection control valve positioned along the drain circuit for controlling the flow through the drain circuit so as to cause reciprocal movement of the nozzle valve element. The leakage limiting valve is integrated into the fuel injector body and positioned along a fuel transfer passage to block the flow of high pressure fuel to a nozzle cavity between injection events. The leakage limiting valve may be a cylindrical valve element positioned between the nozzle valve element and the injection control valve. Alternatively, the leakage limiting valve may be in the form of an annular valve sleeve slidably mounted on one end of the nozzle valve element so as to position the control volume immediately adjacent the injection control valve thereby minimizing the trapped volume and thus the valve response time.

Servo-controlled fuel injector with leakage limiting device

An electromagnetic fuel injection control valve positioned inside a fuel injector, i.e. a unit injector, for providing fast response and high pressure capability while minimizing the size and complexity of the injector. The control valve includes a valve housing having a supply inlet and fuel outlet, a center tube having a center passage and an annular valve seat, a control valve sleeve slidably mounted on the center tube and an actuator assembly having a coil spring, a stator and an armature. The control valve sleeve moves between an open position permitting fuel to flow between the supply inlet and the fuel outlet and a closed position which sealingly engages the annular valve seat for blocking the flow of fuel between the supply inlet and the fuel outlet. The coil spring biases the control valve sleeve in an open position and is positioned around the center tube. The stator is also axially positioned around the center tube and includes multiple poles. The armature connects to the control valve sleeve and reciprocates when solenoid is activated to allow for high pressure fuel injection into the combustion chamber of an internal combustion engine.

Electromagnetic fuel injector control valve

A stepped rotation fuel distribution valve for receiving and conducting metered, pressurized fuel pulses to the combustion cylinders of a diesel engine is provided. The valve includes a fuel distribution shaft rotatably mounted in a valve housing. The shaft includes a fuel discharge port that is sequentially registrable with fuel distributing passages in the housing that ultimately lead to the diesel fuel injectors associated with the combustion cylinders of the engine. A drive mechanism, which may include a stepper motor, intermittently rotates the fuel distributor shaft so that the shaft discharge port dwells in registration with one of the fuel distributing passages at the time a pressurized pulse of fuel is discharged through the shaft discharge port. The drive mechanism may also include either a set of timing gears or a spring coupling to achieve the desired intermittent rotation. In all cases, the intermittent rotation of the fuel distribution shaft prevents the shaft from rotating at a time when the discharge of a highly pressurized fuel pulse applies a high side load to the shaft which in turn can generate high frictional forces between the fuel distribution shaft and the surrounding housing.

Stepped rotation fuel distribution valve

A unit fuel injector is provided comprising an injector body containing a pumping chamber for receiving fuel at a low pressure level from a fuel supply passage for subsequent discharge at a high pressure level, a discharge orifice and a transfer passage communicating with the pumping chamber and the discharge orifice. A valve element is provided for movement between (i) an advanced position wherein the supply passage communicates with the pumping chamber through the transfer passage and (ii) a retracted position wherein communication between the supply passage and the pumping chamber is blocked to allow fuel to flow from the pumping chamber through the transfer passage and out the discharge orifice. The valve element includes a control valve integrally formed with a tip valve, and a force balancing element for tending to balance the forces acting on the valve element by reducing the force tending to bias the valve element toward its second position closing the discharge orifice, when the pressure within the pumping chamber increases to the high pressure level.

Force balanced electronically controlled fuel injector

A hydraulic tappet for use in the fuel injector drive trains of compression ignition or diesel internal combustion engines are provided which optimize injector timing for improved fuel economy. One embodiment of the hydraulic tappet of the present invention includes a dampened pressure regulating feature which determines blow down pressure. A second embodiment of the hydraulic tappet of the present invention includes a dampening load cell feature which allows the blow down pressure of the load cell to be increased and injection timing to be optimally advanced.

Dampened pressure regulating and load cell tappet

A unit fuel injector adapted for periodic injection of fuel into a combustion chamber of an engine at variable times from cycle to cycle under the control of the engine lubrication fluid is provided, comprising an injector body containing an injector cavity and a discharge orifice communicating with one end of the injector cavity to discharge fuel into the combustion chamber, a lubrication fluid timing circuit and a fuel metering circuit separate from the lubrication fluid timing circuit. A lubrication fluid link positioned in the lubrication fluid timing circuit within the injector cavity has a variable effective length which is varied by the operation of a control valve positioned within the lubrication timing circuit to vary the timing of injection. The control valve is operated to control the flow of lubrication fluid in the lubrication fluid timing circuit to control both the timing of injection and the metering of fuel on a cycle by cycle basis. The control valve is operable to be placed in a first position in which lubrication fluid may flow through the lubrication fluid timing circuit into the timing chamber and fuel flow from the fuel metering circuit into the metering chamber is shut off and a second position in which lubrication fluid flow into the timing chamber is shut off. Lubrication fluid is maintained at a higher pressure than the fuel pressure when the control valve is in the first position to stop the movement of a metering plunger to define the metered quantity of fuel thereby avoiding the need for a bias spring. By using lubrication fluid as timing fluid in a timing circuit separate from the fuel metering circuit, the amount of fuel required by the injector and the amount of heated fuel returned to the fuel supply tank is minimized.

Lubrication oil controlled unit injector

A fuel injector for an internal combustion engine includes a main body including a timing bore, a timing plunger disposed in the timing bore, an electronically-operated solenoid valve assembled to the main body, a nozzle having a needle bore and an injection needle disposed in the needle bore which needle is operable under certain conditions to lift so as to initiate fuel injection. Disposed between the main body and the nozzle member is a one-piece adapter which is designed to include an axially-extending metering bore and a needle spring cavity. A metering plunger is disposed within the metering bore and a biasing spring is disposed within the needle spring cavity. At the base of the needle spring cavity is a button which serves as a direct abutment interface between the top of the needle and the bottom of tile biasing spring. The thickness of the button controls the preload on the spring and this is the force which must be overcome by fuel pressure present in the needle spring cavity in order to allow the needle to lift so as to create an injection opening between the needle and the tip of the nozzle for the fuel at high pressure to be injected.

Fuel injection device for an internal combustion engine

The present invention is directed to open nozzle unit fuel injectors for injecting a metered quantity of fuel into the cylinder of an internal combustion engine, as synchronously controlled by a drive train, wherein the unit fuel injector comprises a body with an axial bore and a plunger assembly movable therein between a retracted position and an advanced position. The plunger includes a major diameter section, slidably movable in the axial bore to open and close a fuel supply orifice and a minor diameter section which extends in a bore of a cup portion of the injector body. The cup portion has an internal surface including plural diameter portions connected by an annular step. In accordance with the present invention, the fuel supply orifice is specifically located within the axial bore and the plunger minor diameter section is designed such that when the plunger is moved from its retracted to its advanced position, a portion of the minor diameter section becomes radially engaged, or almost engaged, with one of the plural cup surface sections before the major diameter plunger section closes the fuel supply orifice. The engagement being between the minor diameter portion and one of the plural cup internal surface sections that will be nearest to one another during the entire range of plunger movement from the retracted to advanced positions.

Reduced gas flow open nozzle unit injector

A unit fuel injector is disclosed to be used in a fuel injection system of an internal combustion engine wherein each unit injector is operated independently from one another and in synchronization with the internal combustion engine. Specifically, the unit injector in accordance with the present invention includes a reciprocating plunger assembly within the unit injector that controls fuel metering as well as fuel injection, and a valve device positioned between a minor diameter plunger section and a cup of the unit injector so as to permit fuel flow in one direction for fuel injection and to restrict flow of gases in the opposite direction. The valve device effectively reduces carbon build-up on the injector surfaces and increases injector longevity while reducing maintenance. Moreover, fuel metering is accurately controlled without substantial carboning flow losses.

Unit fuel injector with plunger minor diameter floating sleeve

Growing community of inventors

Columbus, IN, United States of America

Gary L Gant