Abstract: A split-cycle air-hybrid engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft. An expansion piston is slidably received within an expansion cylinder and operatively connected to 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. An air reservoir is operatively connected to the crossover passage. An air reservoir valve selectively controls air flow into and out of the air reservoir. The engine is operable in an Air Expander and Firing (AEF) mode. In the AEF mode, the pressure in the air reservoir is greater than or equal to approximately 5 bar absolute, preferably greater than or equal to approximately 7 bar absolute, and more preferably greater than or equal to approximately 10 bar absolute.

Abstract: A split-cycle air-hybrid engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder. An expansion piston is slidably received within an expansion cylinder. A crossover passage interconnects the compression and expansion cylinders. The crossover passage includes a crossover compression (XovrC) valve and a crossover expansion (XovrE) valve. An air reservoir is operatively connected to the crossover passage. An air reservoir valve selectively controls air flow into and out of the air reservoir. In an Engine Firing (EF) mode, the air reservoir valve is kept closed. In an Air Expander (AE) and an Air Expander and Firing (AEF) mode, the air reservoir valve is kept open for a duration that is at least as long as a duration of the XovrE valve opening event. In an Air Compressor (AC) mode and a Firing and Charging (FC) mode, the air reservoir valve is selectively opened and closed.

Abstract: A split-cycle air-hybrid engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft. An expansion piston is slidably received within an expansion cylinder and operatively connected to 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. An air reservoir is operatively connected to the crossover passage. An air reservoir port connects the crossover passage to the air reservoir. An air reservoir valve is disposed in the air reservoir port. The air reservoir port includes a first air reservoir port section between the crossover passage and the air reservoir valve. The first air reservoir port section has a volume that is less than or equal to a volume of the crossover passage.

Abstract: A split-cycle air-hybrid engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft. An expansion piston is slidably received within an expansion cylinder and operatively connected to the crankshaft. An exhaust valve selectively controls gas flow out of the expansion cylinder. A crossover passage interconnects the compression and expansion cylinders. The crossover passage includes a crossover compression (XovrC) valve and a crossover expansion (XovrE) valve therein. An air reservoir is operatively connected to the crossover passage. An air reservoir valve selectively controls air flow into and out of the air reservoir. In an Air Compressor (AC) mode of the engine, the XovrE valve is kept closed during an entire rotation of the crankshaft, and the exhaust valve is kept open for at least 240 CA degrees of the same rotation of the crankshaft.

Abstract: A split-cycle air-hybrid engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft. An intake valve selectively controls air flow into the compression cylinder. An expansion piston is slidably received within an expansion cylinder and operatively connected to the crankshaft. A crossover passage interconnects the compression and expansion cylinders. The crossover passage includes a crossover compression (XovrC) valve and crossover expansion (XovrE) valve therein. An air reservoir is operatively connected to the crossover passage. An air reservoir valve selectively controls air flow into and out of the air reservoir. In a Firing and Charging (FC) mode of the engine, the air reservoir valve is kept closed until the XovrE valve is substantially closed during a single rotation of the crankshaft such that the expansion cylinder is charged with compressed air before the air reservoir is charged with compressed air.

Abstract: A split-cycle air-hybrid engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft. An intake valve selectively controls air flow into the compression cylinder. An expansion piston is slidably received within an expansion cylinder and operatively connected to 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 therein. An air reservoir is operatively connected to the crossover passage. In an Air Expander (AE) mode and an Air Expander and Firing (AEF) mode of the engine, the XovrC valve is kept closed during an entire rotation of the crankshaft, and the intake valve is kept open for at least 240 CA degrees of the same rotation of the crankshaft.

Abstract: A split-cycle air hybrid engine includes a rotatable crankshaft. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft. An expansion piston is slidably received within an expansion cylinder and operatively connected to 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. An air reservoir is operatively connected to the crossover passage. An air reservoir valve selectively controls air flow into and out of the air reservoir. In an Air Expander and Firing (AEF) mode of the engine, the engine has a residual expansion ratio at XovrE valve closing of 15.7 to 1 or greater, and more preferably in the range of 15.7 to 1 and 40.8 to 1.

Abstract: 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. An expansion piston is slidably received within an expansion cylinder and operatively connected to the crankshaft. A crossover passage interconnects the compression and expansion cylinders. The crossover passage includes a crossover expansion (XovrE) valve disposed therein. In at least one of an Engine Firing (EF) mode, an Firing and Charging (FC) mode, and an Air Expander and Firing (AEF) mode of the engine, the timing of the XovrE valve closing is variable to control engine load, and the engine has a residual expansion ratio at XovrE valve closing of 14 to 1 or greater.

Abstract: A hydro-mechanical system is disclosed for actuating an outwardly opening valve of an engine, such as a crossover passage valve of a split-cycle engine. A developed embodiment includes a body having a plunger cylinder in hydraulic fluid communication with a valve cylinder. A plunger in the plunger cylinder is reciprocated to displace hydraulic fluid into the valve cylinder, the engine valve being opened by the hydraulic fluid displaced by the plunger into the valve cylinder and acting against the valve piston. A valve spring, preferably an air spring returns the engine valve to engage an outwardly facing valve seat to close a gas passage of the engine. Control valves and an energy reusing accumulator, along with valve seating control and lift brake features may also be included.

Abstract: A cylinder head for an engine is provided comprising a monolithic structure forming an upper deck, a fire deck, at least one coolant jacket and a cavity to accommodate a fuel injector or an ignitor therein, the cavity defined by a wall connecting the fire deck with the upper deck. The wall connecting the fire deck with the upper deck, as well as other features of the cylinder head, are preferably arranged to support the fire deck against a deflection thereof by transmitting a mechanical load introduced on a flame face of the fire deck to the upper deck. A method of increasing the stiffness of the cylinder head is also provided.

Abstract: 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.

Abstract: A split-cycle engine includes a rotatable crankshaft. A compression piston is slidably 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 slidably 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 expansion and compression cylinders. The crossover passage includes a crossover compression valve and a crossover expansion valve defining a pressure chamber therebetween. A pilot crossover valve is disposed between the crossover passage and the expansion cylinder.

Abstract: The present invention provides an improved valve seat insert, particularly for split-cycle engines with outwardly opening crossover valves. The improved valve seat insert combines an interference fit section with a threaded section. The interference fit section aligns a valve seat and can prevent rotation of the valve seat insert. The threaded section prevents axial movement of the valve seat insert.

Abstract: A seating control device for a valve, comprising: a vessel for containing a fluid; an upper snubber element translatably receivable in the vessel for controlling the seating velocity of a valve associated therewith; and a lower snubber element translatably receivable in the vessel, adjacent the upper snubber element, presenting a surface to the upper snubber element, for controlling the seating of the valve.

Abstract: The present invention provides a valve actuation system comprising a valve train for actuating a valve, the valve train including actuating elements and a valve lash, and a valve lash adjustment system for adjusting the valve lash, wherein the valve train and the valve lash adjustment system do not share any common actuating elements.

Abstract: The present invention provides a valve actuation system comprising a valve train for actuating a valve, the valve train including actuating elements and a valve lash, and a valve lash adjustment system for adjusting the valve lash, wherein the valve train and the valve lash adjustment system do not share any common actuating elements.

Abstract: A hydraulic variable compression ratio (VCR) piston for use in an internal combustion engine. The piston is a two-part piston, in which a gudgeon pin carrier slides within an outer sleeve. A variable volume upper chamber is formed between the top of the gudgeon pin carrier and the end of the outer sleeve. When the upper chamber fills with oil, its volume increases, and the overall piston geometry is longer. This reduces the piston clearance in the cylinder and increases cylinder pressure. At a given maximum cylinder pressure or at a given rate of increase of cylinder pressure, oil from the upper chamber is relieved by using a rate-sensitive pressure relief valve.

Abstract: A split-cycle 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 reciprocates through intake and compression strokes during a single rotation of the crankshaft. An expansion piston is slidably received within an expansion cylinder and operatively connected to the crankshaft such that the expansion piston reciprocates through expansion and exhaust strokes during a single rotation of the crankshaft. A crossover passage interconnects the expansion and compression cylinders. The crossover passage includes crossover compression (XovrC) and crossover expansion (XovrE) valves defining a pressure chamber therebetween. At least one of the XovrC and XovrE valves is a balanced valve.

Abstract: A hydro-mechanical system is disclosed for actuating an outwardly opening valve of an engine, such as a crossover passage valve of a split-cycle engine. A developed embodiment includes a body having a plunger cylinder in hydraulic fluid communication with a valve cylinder. A plunger in the plunger cylinder is reciprocated to displace hydraulic fluid into the valve cylinder, the engine valve being opened by the hydraulic fluid displaced by the plunger into the valve cylinder and acting against the valve piston. A valve spring, preferably an air spring returns the engine valve to engage an outwardly facing valve seat to close a gas passage of the engine. Control valves and an energy reusing accumulator, along with valve seating control and lift brake features may also be included.