Abstract: A system for controlling fuel flow in an internal combustion engine receives a command specifying a desired fuel flow rate from an electronic control module. The system generates a feedforward estimate of actuator current required to produce the desired flow rate. This estimate is combined with a fueling current offset value generated using a proportional-integral feedback controller. A differential pressure between the fuel rail and cylinder gas is converted, by surface interpolation based on a lookup table, to an estimate of actual fuel flow rate. The difference between this actual fuel flow rate and the desired flow rate is provided to the feedback controller as an error signal. The feedback controller preferably uses different gain values depending on an operating mode of the engine (speed control and torque control modes).
Abstract: An injection rate shaping nozzle assembly for a fuel injector is provided which includes a closed nozzle valve element and a rate shaping control device including an injection spill circuit for spilling a portion of the fuel to be injected to produce a predetermined time varying change in the flow rate of fuel injected into a combustion chamber. The spill circuit includes a spill passage integrally formed in the nozzle valve element. The rate shaping control may include a spill valve for controlling the spill flow through the spill circuit to create a low injection flow rate followed by a high injection flow rate. The spill passage may communicate with the injector nozzle cavity between injection events or alternatively may be blocked to prevent spill flow between injection events. The rate shaping control device may include a spill accelerating device in the form of a spill chamber formed in the nozzle valve element for creating a rapid increase in the spill flow rate.
Abstract: A ring compressor is provided including a resilient compression band for encircling, and applying a compression force to, the ring, and a band actuation device connected to the compression band for moving the compression band between a decompressed position in which the band ends are spaced and a compressed position in which the band ends are positioned in end to end, nonoverlapping abutment preventing further compression of the ring. The band actuation device may include an outer band encircling the resilient compression band and a hand operated lever assembly. The outer band provides radial support to the ends of the compression band to guide the first and second ends radially into abutment. A ring end axial alignment device may also be provided for guiding the ends of the compression band into axially aligned abutment when in the compressed position.
Abstract: A system and method for controlling an air-fuel ratio of an internal combustion engine using a ratio of cylinder pressures measured within at least one cylinder. The air-fuel ratio control system includes an electronic control module (ECM) which computes a measured cylinder pressure ratio of the cylinder pressure measured at a predetermined crank angle before top dead center and the cylinder pressure measured at a predetermined crank angle after top dead center. The measured cylinder pressure ratio is compared with an optimal cylinder pressure ratio. Based upon the results of this comparison, the ECM then determines an adjusted air-fuel ratio which would modify the measured pressure ratio to equal the optimal pressure ratio. This system controls the air-fuel ratio by measuring the quality of combustion without the need to measure the amount of air or fuel actually delivered to the engine.
Abstract: An injection rate shaping nozzle assembly for a fuel injector is provided which includes a closed nozzle valve element and a rate shaping control device including an injection spill circuit for spilling a portion of the fuel to be injected to produce a predetermined time varying change in the flow rate of fuel injected into a combustion chamber. The spill circuit includes a spill passage integrally formed in the nozzle valve element. The rate shaping control device may include a spill accelerating chamber in formed in the nozzle valve element for creating a rapid increase in the spill flow rate. A spill circuit purge device is provided to remove fuel from the spill circuit and accelerating chamber between each of the injection events thereby ensuring an unimpeded, effective spill fuel flow during the next spill event.
Abstract: Manufacture of a liquid cooled cylinder head for an internal combustion engine is described which reduces incidence of casting fins that may block or impede coolant flow through the cylinder head. The head is cast without internal liquid coolant passages to interconnect the first and second cooling cavities. An opening is machined through an outer surface of the head to define a passage interconnecting the first and second cooling cavities to provide for communication of cooling liquid therebetween. The opening formed by machining through the outer surface of the head is closed. Throat area of the the passage may be selected to control coolant exchange between the first and second cooling cavities and additional passages may be machined in each head to provide additional coolant interchange or to vent air from the cooling cavities.
Abstract: A turbocharger wastegate control system is responsive to electrical control signals to control the position of a wastegate valve positioned within an exhaust bypass conduit of the turbocharger. In one embodiment, the control system includes an air pressure control device having an inlet port receiving boost air pressure from an intake manifold connected to the turbocharger, an outlet port providing wastegate air pressure to a wastegate actuator and a vent to atmosphere. A number of air flow control switches are responsive to electrical control signals to control the levels of boost air pressure and vented air to thereby provide a plurality of discrete wastegate air pressure levels to the wastegate actuator. In another embodiment, the control system includes an electrically controllable wastegate actuator responsive to boost air pressure and electrical control signals to modulate the position of the wastegate actuator plunger.
Abstract: A fuel measurement and control system for a gaseous fuel engine having a solenoid actuated fuel flow control valve which is electronically actuated to control a desired metering duration when the control system is operating in a fuel flow control mode. The fuel measurement and control system further includes mode control valve for switching the control system between a fuel flow control mode and a positive fuel shutoff mode, wherein the fuel flow control valve is prevented from opening when the control system is operating in a positive fuel shutoff mode. The fuel flow control valve includes a pressure balance chamber to balance the biasing forces acting on the valve from the gaseous fuel, wherein gaseous fuel is introduced into the pressure balancing chamber to provide the balancing forces.
Abstract: A load driver system for integrally controlling the flow of current through a number of inductive loads of an internal combustion engine, particularly the flow of current through a fuel injector solenoid and an engine brake solenoid during the operation of an engine cylinder, is provided. In one embodiment of the load driver system, a single multiplexed high side driver is connected to inputs of both solenoids, and separate low side drivers are connected to outputs of each of the solenoids. In an alternative embodiment, separate high side drivers are connected to inputs of each of the solenoids, and a single multiplexed low side driver is connected to the outputs of the solenoids.
Abstract: An improved method and system for automatically continuously replacing an engine's used lubricating oil with fresh lubricating oil throughout operation based on engine operating conditions is disclosed. The present system includes an injection control device for injecting small amounts of used lube oil into the engine's fuel system and an auxiliary flow control device for directing controlled quantities of fresh oil into the engine's lube oil system. An electronic controller is provided to vary the amount of used lube oil injected into the oil system based on the severity of engine operation. The process periodically determines an engine operating severity value, i.e. fuel consumption value, for an interval of engine operation and calculates a base line quantity of oil for injection based on the current fuel consumption of the engine during the current interval.
Abstract: An engine control system is operable to provide an engine fueling rate equal to the larger of a first engine fueling rate at which the resulting engine torque is limited by a maximum input torque capacity of a presently engaged gear ratio of the transmission and a second engine fueling rate at which the resulting engine torque is limited by a nominal input torque capacity of the transmission. The foregoing technique can be enabled at all times, or alternatively only after determination that the vehicle is experiencing deceleration under heavy engine load conditions. The engine control system may be further operable to determine a third engine fueling rate at which the resulting engine output torque is limited by a maximum operating torque capacity of the transmission propeller shaft, as well as a fourth engine fueling rate at which the resulting engine output torque is limited by a maximum operating torque capacity of the drive axle connected thereto.
Abstract: A compression braking system is provided which permits an engine's exhaust valves to be operated by fuel pressure during a braking mode independently of the engine's mechanical actuating elements and associated control limitations. The present braking system includes a high pressure fuel supply including a high pressure fuel accumulating device for accumulating and temporarily storing high pressure fuel and an actuator device including an actuator piston operatively connected to the engine exhaust valve and a brake actuating valve for controlling fuel flow from the accumulating device to the actuator piston. The pressure of the fuel acting on the actuator causes movement of the exhaust valve. The system may include a pressure regulator for decreasing the accumulator fuel pressure to a more appropriate actuation fuel pressure to minimize high pressure joints and leakage. A improved sealing means may be provided for preventing leakage around the actuator piston.
Abstract: A system for controlling the temperature of recirculated exhaust gas supplied to an internal combustion engine is provided. In one embodiment, the system includes a heat exchanger having the recirculated exhaust gas flowing therethrough and further having coolant fluid flowing therethrough. A control valve is disposed within the flow path of the coolant fluid, and the valve position is modulated to vary the rate of coolant fluid flow through the heat exchanger, thereby controlling the temperature of the recirculated exhaust gas supplied by the heat exchanger. In another embodiment, the heat exchanger defines a number of exhaust gas flow passages therethrough and a number of gas flow control valves are disposed between the exhaust gas inlet of the heat exchanger and the number of exhaust gas flow passages.
Abstract: An integrated fuel injector and ignitor assembly is provided which includes an injector body, a fuel control valve and an ignition device. The components are packaged to create a compact assembly for positioning within an injector mounting bore and particularly in a mounting bore of an existing diesel engine. The assembly may include a fuel reservoir for accumulating fuel for injection so as to stabilize the injection pressure. Also, the ignition device may include an ignition coil mounted on the injector body and a replaceable ignitor electrode cartridge mounted on an opposite end of the injector body to permit simple, cost effective replacement of the electrodes/spark plug.
Abstract: In accordance with preferred embodiments of the invention a timing adjustment device includes a cam follower that is engaged between an overhead cam and an injector rocker arm, and is mounted on a rotatable eccentric shaft. The geometry of the eccentric shaft and cam follower is designed so that, as timing is varied by rotation of the eccentric shaft, no change is produced in the vertical height of the rocker arm when the cam shaft is on the outer base circle and the injector is bottomed, in order to assure that the "mechanical crush" of the PT type injector is constant despite changes in timing. In a first application of the timing arrangement, it is used together with a simple injector, which does not utilize a multi-plunger arrangement to form a hydraulic link, to achieve lower parasitic losses.
Abstract: A hybrid gaseous fueling system having a low pressure supply and a high pressure supply is disclosed. This system provides the advantages of fueling with a low pressure charge during steady state operation and also provides a way to more rapidly smooth engine transients resulting from changes in engine operating characteristics such as speed or load by modulating high pressure fueling of the engine. Furthermore, air/fuel ratio control may be readily integrated into this system. In addition, start-up of the engine is performed using more fuel from the high pressure supply than the low pressure supply up to a predetermined level of engine operation. At that level and beyond, low pressure fueling is greater than high pressure fueling.
Abstract: A coated piston ring and method of manufacture for internal combustion engines and compressors. The piston ring having a outer peripheral surface that is coated with a thin substantially final finish spray wear resistant coating for contacting the cylinder wall. The material coating is deposited by high velocity oxygen fuel spray apparatus and a sharp bottom edge is lapped thereon for contacting the cylinder wall of the apparatus. The method of manufacturing comprising rotating a plurality of piston rings about a central axis while the high velocity oxygen fuel gun sprays molten coating material thereon. The molten coating material forming a mechanical interlock with the ring blank to produce a substantially final finish spray coating on the periphery of the piston rings.
Abstract: A distortion reducing load ring disposed and connected between a fuel injector and a clamping device. The load ring functions as an intermediary for transmitting a static clamping load from the clamping device to the fuel injector body. The load ring includes a substantially cylindrical shaped main body having a bore extending therethrough between an upper portion and a lower portion. The upper portion of the main body being adapted for receiving a clamping load from the clamping device. The lower portion defining an annular ring for contacting the upper surface of the fuel injector body. A convex shaped portion connecting between the lower portion and the upper portion for increasing the resistance to bending of the load ring. The geometric relation of the load ring is utilized to transfer the static clamping load from the clamping device to a substantially central region of the fuel injector body.