摘要:
A hydraulic hybrid vehicle includes elements such as a hydraulic pump (104) driven by an internal combustion engine (102) and arranged to draw in low pressure fluid and pump the fluid at high pressure to an accumulator (108) hydraulic motor (110) is powered by the pressurized fluid. Safety processes are provided for detecting and addressing a number of conditions that may arise in the operation of the hydraulic hybrid vehicle, including an initialization procedure for start-up of the vehicle, a shut-down procedure, and procedures for detecting and responding to failure of the pump or motor, internal and external fluid leaks, and non-responsive actuation and mode control systems.
摘要:
This invention sets forth a commercially viable diesel combustion system that meets environmentally acceptable levels of NOx emissions (i.e. 0.2 g/bhp-hr or lower across a full map of engine speeds and loads) without the need for use of NOx aftertreatments, and simultaneously maintains engine-out PM emissions relatively close (e.g. with smoke levels at or below 3 BSN) to environmentally acceptable PM post-aftertreatment levels. The invention achieves these results by operating within a unique combination of parameters. These parameters comprise: (1) charge-air oxygen concentration below 16%, preferably between 10% and 15%, more preferably between 11% and 14%, and most preferably between 12% and 13.5% for virtually all engine operating conditions (but not necessarily at no-load or low load conditions), (2) fuel injection pressures at or exceeding 1800 bar, preferably exceeding 2100 bar, more preferably exceeding 2300 bar, and most preferably exceeding 2500 bar, at most engine speeds and loads, and (3) charge-air mass/fuel mass ratio between 25:1 and 45:1 for medium and high loads. Furthermore, the system is preferably run continuously slightly lean of stoichiometry, providing just enough excess oxygen to facilitate completeness of combustion and to maintain an exhaust oxygen level sufficient for continuous trap regeneration at a balance point in operation.
摘要:
A method is provided for close control and adjustment of in-cylinder oxygen concentration levels together with boost adjustments to minimize harmful emissions during transients in engines which utilize late direct cylinder injection of fuel. EGR flow rates are adjusted in a closed loop, linked fashion together with boost pressure changes during transients, to maintain intake charge-air oxygen concentration and boost levels within critical ranges for controlled temperature, low emission combustion. Changes in fuel feed into the cylinder are made to wait for or follow changes in the boost level of charge-air into the cylinder for combustion. Temporary fuel levels are not allowed to exceed desired fuel/oxygen ratios during transients, by controlling fuel feed responsive to the level of boost of charge-air being taken into the cylinder for combustion.
摘要:
A free-piston engine that comprises a pair of parallel side-by-side combustion cylinders, a free-floating combustion piston mounted in each of said combustion cylinders for reciprocating linear motion therein, responsive to successive combustion events within said combustion cylinders, at least one pumping piston (101) extending from and fixed to each of said combustion pistons, a hydraulic cylinder (107) receiving each of said pumping pistons (101) for reciprocating motion therein, a shuttle cylinder (103, 110) axially aligned with and in fluid communication with each of said hydraulic cylinders and a shuttle piston (102, 111) mounted in each shuttle cylinder (103, 110) for reciprocating motion therein, connectors (104) for rigidly and axially connecting each shuttle piston (102,111) to a pumping piston (101), a transfer tube (109) providing fluid communication respectively between said shuttle cylinders (103, 110), and a flexible linkage (112) passing through said transfer tube (109) and connecting the shuttle pistons (102, 111).
摘要:
A hydraulic accumulator (20) includes a rigid tank (27) containing a flexible but non-elastic bladder (21) formed of a metal foil and separating the interior of the tank into a gas space and a liquid space. The gas and liquid spaces respectively communicate with exterior sources of gas and liquid through fixtures (22,24) provided on the accumulator tank. One of the fixtures (24) is provided with an anti-extrusion valve (25) to prevent the bladder from being forced out through the fixture. In one preferred embodiment the bladder is a bellows. in another preferred embodiment the accumulator tank is provided with a vent in communication with the liquid space within the tank to allow for venting of any gas separating from the liquid and accumulating within the liquid space.
摘要:
An air bottoming powertrain, suitable for use in automobiles includes an internal combustion engine (18), a compressor (1) which receives gaseous working fluid and compresses it to an elevated pressure, a cooler (16) for operating the compressor isothermally, an expander (4) for deriving work from the compressed gas and a heat exchanger (3) located in the compressed gas line for indirect heat exchange between the compressed working fluid and exhaust gas from the internal combustion engine. The expander may have a cylindrical barrel with a plurality of cylinders arranged in a circle and open at one end face of the cylinder barrel, which end face is sealed closed by a valve plate. The cylinder barrel and valve plate allow relative rotation therebetween to drive an output shaft, driven by compressed gas from the compressor.
摘要:
An internal combustion engine includes a cylinder (21), a head (58) closing one end of the cylinder (21) and a piston (24) slidably mounted in the cylinder (22) for reciprocating motion in the usual manner, wherein reciprocation is converted into rotary motion for example, by a conventional crankshaft. The top surface (32) of the piston (24), cylinder head (58) and cylinder (21) serve as walls defining a system chamber (70) with a pocket (36) formed in one of the system chamber walls for receiving fuel and serving as a combustion chamber (70) for localized combustion therein. In one disclosed embodiment, the cylinder (21) is divided into two sections (21 and 22) with thermal insulation (14, 30) serving as a heat barrier disposed between the two sections (21 and 22) and the piston (24) has a hollow interior containing one or more heat shields (41, 42) spanning the hollow interior.
摘要:
A method of operation of an internal combustion engine to minimize NOx emission in the exhaust gas involving the detection of the load on the vehicle engine as either a low load or a high load. When a low load is detected, unthrottled air and a quantity of fuel providing for a lean combustion condition are mixed with the injection (4) of fuel adjacent top dead center during the compression stroke. When a high load condition is detected, throttled air and a quantity of fuel governed by the sensed oxygen content of the exhaust gas are mixed in an approximately stoichiometric ratio with the injection (4) at a much earlier time than the injection at low load, preferably during the intake stroke.