37 results about "Split cycle engine" patented technology

The present invention generally relates to providing an air supply for components associated with an engine. More particularly, the present invention relates to a system and method for using compressed air generated by a split-cycle engine to power components such as valves or air springs associated with the split-cycle engine.

A split-cycle engine includes a crankshaft. A compression piston is received within a compression cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke during a single rotation of the crankshaft. An expansion piston is received within an expansion cylinder and operatively connected to the crankshaft such that the expansion piston reciprocates through an expansion stroke and an exhaust stroke during a single rotation of the crankshaft. A crossover passage interconnects the compression and expansion cylinders. The crossover passage includes a crossover compression (XovrC) valve and a crossover expansion (XovrE) valve defining a pressure chamber therebetween. The crossover compression valve is timed to open when the pressure in the compression cylinder is less than the upstream pressure in the crossover passage at the crossover compression valve.

Split cycle engine and method in which output power and power density are increased in some embodiments with a turbocharger or supercharger which increases the pressure in the compression cylinder and also increases the power output of the engine without a corresponding decrease in the efficiency of the engine (work done per unit fuel). In other embodiments, the engine is used for braking, and the energy produced by braking is stored pneumatically and then used in driving the compressor.

A split-cycle engine includes an expander, the expander including an expansion piston received within an expansion cylinder. A compressor includes a compression piston received within a compression cylinder. A crossover passage interconnects the compression and expansion cylinders. An intake manifold is connected to the compression cylinder. A boosting device providing a 1.7 bar absolute or greater boost pressure level is connected to the intake manifold. An intake valve is disposed between the intake manifold and the compression cylinder. The intake valve closing is timed to provide a compressor volumetric efficiency of 0.75 or greater. A compressor displacement volume is sized relative to an expander displacement volume such that the combination of compressor displacement volume and boost pressure level provides an expander volumetric efficiency relative to ambient conditions that is 0.90 or greater.

A split-cycle internal combustion engine (ICE) is provided, comprising a compression cylinder, an expansion cylinder and a crossover valve having a valve cylinder housing inside a shuttle and a combustion chamber structure defining a combustion chamber. The shuttle is configured to perform reciprocating motion inside the valve cylinder synchronously with a compression piston and an expansion piston, thereby alternatingly fluidly coupling and decoupling the combustion chamber with the compression cylinder and with the expansion cylinder, selectively. Sealing rings positioned between the valve cylinder and the shuttle prevent gas leaks between them during the reciprocating motion. In some embodiments, a phase shift between the pistons may be set or varied by a piston phase transmission gear. A bi-directional fluid flow split-cycle internal combustion engine (ICE) is also provided having a first cylinder, a second cylinder, a combustion chamber and a single crossover valve fluidly communicating them. A three-cylinders split-cycle internal combustion engine (ICE) is also provided, having a compression cylinder and a combustion chamber, wherein a single crossover valve alternatingly fluidly couples the combustion chamber to two or more expansion cylinders.

An engine includes a crankshaft rotatable about a crankshaft axis. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft such that the compression piston is operable to reciprocate through an intake stroke and a compression stroke during a single rotation of the crankshaft. An expansion (power) piston is slidably received within an expansion cylinder and operatively connected to the crankshaft such that the expansion piston is operable to reciprocate through an expansion stroke and an exhaust stroke during a single rotation of the crankshaft. At least two crossover passages interconnect the compression and expansion cylinders. Each of the at least two crossover passages includes a crossover compression (XovrC) valve and a crossover expansion (XovrE) valve operable to define a pressure chamber therebetween. The engine controls and maximizes engine efficiency at part-load by utilizing only selected crossover passages.

A split-cycle engine with disc valve includes a crankshaft, a power cylinder and a compression cylinder. A gas crossover passage interconnects the compression cylinder and the power cylinder. An air intake port circumscribes a periphery of the compression cylinder and defines an outer valve seat. An annular ring having a generally central opening is disposed between the compression cylinder and the air intake port and forms a washer valve for opening and closing the air intake port. A disc valve member is concentrically mounted over the central opening of the annular ring. The disc valve member includes a piston portion having a sidewall biased into engagement with the outer valve seat for controlling flow between the compression cylinder and the gas crossover passage.

Crossover valve systems and corresponding methods offer an effective means to overcome large opening pressure force, or provide reasonable gas flow area, or both. In an exemplary embodiment, a crossover valve system for a split-cycle engine having a power cylinder and a crossover passage comprises first and second crossover valves, each valve opening outwardly away from the power cylinder and providing fluid communication between the power cylinder and the crossover passage, with the diameter of the second crossover valve being larger than the diameter of the first crossover valve; and an actuation mechanism operative to open the first crossover valve, then the second crossover valve after a predetermined delay to allow a certain rise in the pressure inside the power cylinder, resulting in much smaller differential pressure forces across the crossover valves, larger flow areas, or both.

An engine includes a rotatable crankshaft and an expansion piston slidably received within an expansion cylinder and operatively connected to the crankshaft. A crossover passage including walls connects a source of high pressure gas to the expansion cylinder. A crossover expansion (XovrE) valve is operable to control fluid communication between the crossover passage and the expansion cylinder. The XovrE valve includes a valve head and a valve stem extending from the valve head. A fuel injector operable to inject fuel into the crossover passage includes a plurality of spray holes disposed in a nozzle end and aimed at an at least one target at which fuel emitting from the spray holes is directed to form at least one spray pattern. The at least one target is located above a seated position of the XovrE valve head and between the walls of the crossover passage and the XovrE valve stem.

Split cycle engine that runs on gaseous fuels such as natural gas and synthesis gas (syngas) and to a method of operating the same. The engine includes a first compression chamber for compressing the gaseous fuel, means for supplying the gaseous fuel to the first compression chamber at a level of concentration that prevents predetonation of the fuel during compression, a second compression chamber for compressing air, a combustion chamber in which the compressed fuel and air are combined to reduce the concentration of the fuel to a level that allows the fuel to burn and expand in the combustion chamber, and an expansion chamber having an output member which is driven by expanding gas from the combustion chamber. Turbochargers or blowers pressurize and increase the volume of the fuel and air delivered to the respective compression chambers, and the concentration of the fuel is progressively reduced by the injection of air at spaced intervals as the fuel travels toward the compression chamber.