Abstract: A method of forming a wear-resistant coating for internal combustion engine component parts which allows the part to remain dimensionally stable under severe engine operating conditions is provided. The coating is formed by a two step method. First, the engine part is coated with chromium to form a chromium base layer. Second, the chromium coated part is subjected to a reactive gas plasma in a reaction chamber at an elevated temperature and under an applied electrical potential. The gas of the plasma reacts with the chromium to form the wear-resistant layer. Preferably, the reactive gas is nitrogen which reacts with the chromium to form a chromium nitride surface layer on the chromium base layer.
Abstract: A process for forming a balanced flywheel assembly from a cast metal hub having at least one cast-in pick up and a ring gear having an inside shrink-fit surface with a predetermined diameter at ambient temperature by heating a ring gear sufficiently to cause the diameter of the inside shrink-fit surface to become larger than the diameter of a ring gear mounting surface of the cast metal hub, mounting the ring gear on the ring gear mounting surface, cooling the ring gear to shrink fit the ring gear onto the ring gear mounting surface, and balancing the cast metal hub and the ring gear assembly; various surfaces being formed on the cast metal hub by turning.
Abstract: A high pressure unit fuel injector includes a timing chamber formed between upper and lower plungers of the injector for controlling the timing of injection. A timing chamber relief valve is provided for performing at least one of the functions of (1) draining timing fluid from the timing chamber during an injection stroke responsive to pressure in the timing chamber for maximizing the pressure of fuel in the injection chamber under low speed operating conditions without exceeding a pressure capability of the injector under high speed operating conditions, and (2) for collapsing the timing chamber in a controlled manner at termination of injection so as to prevent secondary injection from occurring. The relief valve structure is wholly formed above the lower plunger, preferably within the upper plunger above the timing chamber. Thereby, assembly and maintenance operations on the valve are facilitated.
Abstract: Cast iron gears, such as those used as cam gears on engines and as used for fuel injection gear pumps, which have a hub and a rim that are thick in comparison to the relatively thin web used to interconnect the hub with the rim and a process by which such iron gears can be cast, especially in a vertical orientation. To eliminate porosity problems, single flow channel of substantial thickness is incorporated into the mold cavity which forms a flow rib that runs radially between the hub and rim of the gear being formed. To compensate for both the added weight of the rib that is produced on the web of the resultant gear, as well as to counterbalance the effect caused by the presence of a single rib, at least one opening is formed in the web at each side of the rib.
Abstract: The present invention relates to an internal combustion engine and more particularly to an internal combustion engine which includes a turbocharger system having at least one smaller exhaust gas turbocharger and at least one larger exhaust gas turbocharger, as well as means for controlling the exhaust gas and intake air flow to the respective turbochargers. The turbochargers and control means are interconnected to provide pressurized intake air throughout the entire operating range of the internal combustion engine, while effectively bypassing the smaller exhaust gas turbocharger during operating conditions which produce high exhaust gas volumes. The operating characteristics of this turbocharger system are matched with the operating range of an internal combustion engine to provide improved performance, efficiency, transient response and reliability, while reducing maintenance and undesirable emissions.
Abstract: Fuel injector for an internal combustion engine which has a timing chamber bore in its body intersecting at an acute angle with an auxiliary bore. These bores are fuel-receiving passages exposed to the pressure of injection. A radiused intersection between the walls of the respective bores reduces the concentration of stress within the fuel injector, allowing the injector to withstand the high injection pressures of mechanical pressurization. An electrochemical machining method and fixture for machining the intersection between the bores of a fuel injector body or other workpiece is also disclosed.
Abstract: An improved master cylinder for use with an engine compression braking system includes a two-piece telescoping piston which traps a column of fluid therewithin to establish a solid column or piston for a limited length of travel of the piston. Upon achieving a particular predetermined displacement, the fluid column trapped within the two-piece piston is released, thus rapid piston movement is achieved without overtravel which may open exhaust valves of the engine to a distance wherein interference with the piston occurs. The two-piece telescoping piston is actuated in accordance with an injector pushtube or other combinations such as exhaust or intake valve cam/pushtubes.
Abstract: A fastener which allows a user to easily utilize the Torque Angle Method to provide a predictable clamp load to a clamped element. The fastener includes an externally threaded shank portion, a torque receiving portion integrally connected on one end of the shank portion and a radially extending flange located between the shank portion and the torque receiving portion. The flange includes a pair of cut-out notches located on the peripheral edge of the flange which are formed prior to initial tightening of the fastener and are spaced apart at a predetermined angular distance to allow a user to utilize the Torque Angle method to provide predictable clamp load across a joint connection.
Abstract: A fuel leakage prevention system for preventing undesired leakage of fuel into the combustion chambers of an internal combustion engine equipped with a pressure/time, cam actuated unit fuel injection system. The system includes a main housing containing an evacuatable chamber adapted to be connected by a first fluid conduit to a source of sub-atmospheric pressure by a check valve and manual shut off valve. The evacuatable chamber is also adapted to be fluidically connected to a common rail supplying fuel to the injectors by a solenoid controlled valve which is open during engine shutdown and closed during engine operation whereby fuel is withdrawn from the injectors by the vacuum upon engine shutdown.
June 21, 1991
Date of Patent:
November 3, 1992
Cummins Engine Company, Inc.
John C. Williams, Kevin W. Westerson, George L. Muntean, Thomas W. Sullivan
Abstract: A turbocharger for an internal combustion engine is provided having a turbine section responsive to the engine exhaust gas flow and a compressor section communicating with the engine intake manifold. A pressure responsive adjustable fuel pump is in communication with the engine combustion chambers. A wastegate unit with an adjustable valve disposed within a bypass passageway formed in the turbine section is provided for regulating the diverion of a predetermined amount of exhaust gas flow away from a turbine wheel within the section. The unit valve is biased to assume a closed position with respect to the bypass passageway. A multiport connection having an interior cavity is provided with a first port in pressure communication with the fuel pump; a second port in pressure communication with the intake manifold; and a third port in pressure communication with the wastegate unit.
Abstract: A throttle valve positioned at either the inlet or outlet of an internal combustion engine aftercooler has the advantages of increased air charge temperature and lower air pressurization at low ambient air temperatures. The throttle valve reduces the effective aftercooler cross-sectional area available to transfer heat energy from the air charge to the atmosphere. The air velocity increase through the restricted aftercooler also decreases the heat transferred to the atmosphere. The air charge thus retains more heat energy in the form of higher intake air charge temperatures. The throttle valve also imposes a flow restriction to the aftercooler, causing an increased pressure differential across the aftercooler, which decreases the amount of pressure boost actually delivered to the engine cylinder to desirable pressure levels.
Abstract: An exhaust port liner assembly for use in a cylinder head of a vehicle engine composed of spaced inner and outer tubular metal shells having a mass of heat insulating material within the spaced shells and a gasket within the said spaced shells adjacent the outlet port. A metal cylinder head is cast around the spaced inner and outer shells while a removable insert is positioned within the spaced shells adjacent the outlet port. After casting of the metal cylinder head, the insert is removed and replaced by a gasket member.
Abstract: A piston assembly for use in a piston cylinder of an engine is disclosed. The piston assembly includes a piston rod which connects the piston assembly to a crankshaft. The piston rod has a pin receiving opening at an upper end. A piston head having a transverse bore is connected to the piston rod. A piston pin is disposed through the pin receiving opening of the piston rod and the transverse bore of the piston head. The piston pin connects the piston head to the piston rod and has an axial bore. A piston skirt is connected to the piston head. The piston skirt has a transverse bore and an oil reservoir formed in the upper surface. At least one piston skirt pin is disposed through the piston pin axial bore and the transverse bore of the piston skirt to connect the piston skirt to the piston pin. This connects the piston skirt to the piston head. A fastening device secures the piston skirt pin in position within the piston skirt and the piston pin.
Abstract: A turbocompound engine having a power turbine bypass valve and a control module for controlling opening and closing of the bypass valve. The control module opens the bypass valve for various operating conditions, such as at high altitudes, low speed/high load, and transient load conditions for improved engine operation.
November 30, 1990
Date of Patent:
September 1, 1992
Cummins Engine Company, Inc.
Peter V. Woon, Amarjit Ghuman, Rodoljub Radovanovic, Brian E. Walsham, Steven C. Francis
Abstract: A turbocompound engine having a power turbine bypass valve and a control module for controlling opening and closing of the bypass valve. The turbocompound engine is capable of operating in a compression braking mode, and the control module opens the bypass valve in response to actuation of the compression braking, resulting in improved braking.
September 25, 1990
Date of Patent:
June 9, 1992
Cummins Engine Company, Inc.
Robert M. Brooks, Timothy P. Lutz, John Stang
Abstract: A ceramic link element suitable for use as a component in the drive train of an internal combustion engine is provided. The link includes a central shaft portion with opposed spherical terminal ends that contact correspondingly configured elements in the drive train. The ceramic link element is formed, preferably by injection molding, to be substantially free from flaws and to have maximum pore diameters, preferably a maximum pore diameter of 150 um or less on the shaft and 40 um or less on the spherical terminal ends, to produce a link with optimum mechanical strength. When these pore dimensions are met and the degree of sphericity of the spherical terminal ends is 20 um or less, the ceramic link exhibits increased mechanical strength, durability and reliability. A method of forming a ceramic link having the aforementioned characteristics is also provided.
Abstract: The present invention provides a lubricant circulation system for a rock drill bit which circulates a flow of lubricant over the bit bearing surfaces to keep the bearings optimally lubricated and free to particulate contaminants from the drilling process. A lubricant pumping assembly, including a pair of nested gerotor pump elements is attached to either the drill bit cutting element or support structures so that one of the gerotors is driven by rotation of the bit cutting element or related structures and the other gerotor rotates freely. The gerotors have a corresponding tooth and recess configuration that pulls lubricant from the lubricant supply under positive pressure into a variable sized cavity formed as the gerotors rotate relative to each other and then forces lubricant to the bearing surfaces. Lubricant may optionally be pumped back to the lubricant supply with continued rotation of the gerotors or out of the journal area with the drilling cuttings for return to the surface.
Abstract: An electro-hydraulic position-servo device to quickly and accurately position a stop element is provided for use with a positive displacement fuel injection system, wherein a shuttle is used to positively displace pre-metered slugs of fuel to unit injectors. The stop device is operatively associated with a control shaft having at least one helical surface thereon; the stop element and control shaft slidably located within a housing. The housing permits communication between at least one pressurized fluid source and a drain line by way of a chamber within which the control shaft is located. Thus, by simply rotating the control shaft from rotational drive means, the control shaft will assume an axial position determined by the orientation of the helical surface with respect to the supply and drain lines. The device is adjustable by rotation of the shaft to a new position with the re-orientation of the helical surface.
Abstract: A unit fuel injector adapted to receive fuel from a fuel supply at relatively low pressure and adapted to inject fuel at relatively high pressure into the combustion chamber of an internal combustion engine is provided, comprising an injector body having a first internal bore and an injector orifice and a plunger mounted for reciprocating movement within the first internal bore to define a variable volume fuel pressurization chamber including a cam actuated upper plunger portion and a lower plunger portion mounted in the first internal bore between the variable volume fuel pressurization chamber and the upper plunger portion. While the upper plunger portion is in its retracted position, low pressure fuel from the fuel supply is supplied to the variable volume fuel pressurization chamber.
Abstract: A unit fuel injector assembly (88) periodically injects fuel of a variable quantity on a cycle to cycle basis as a function of the pressure of fuel supplied to the injector from a source of fuel and at a variable time during each cycle as a function of the pressure of the timing fluid supplied to the injector from a source of timing fluid. A reciprocating plunger assembly (146) is received within the injector body (106) and includes an upper plunger section (148), a lower plunger section (150) and an intermediate plunger section (152) in order to define a variable volume timing chamber (138), a variable volume injection chamber (162) and a variable volume compensation chamber (176).