Patent ID: 7353786
Filing Date: 2008-04-08
Classification: F02B,F02D,Y02T

Abstract:
1. A split-cycle air hybrid engine comprising: a crankshaft rotatable about a crankshaft axis; a power piston slidably received within a power cylinder and operatively connected to the crankshaft such that the power piston reciprocates through an expansion stroke and an exhaust stroke during a single rotation of the crankshaft, the power cylinder being selectively controllable to place the power piston in a power mode or an idle mode; a compression piston 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, the compression cylinder being selectively controllable to place the compression piston in a compression mode or an idle mode; an air reservoir operatively connected between the compression cylinder and the power cylinder and selectively operable to receive compressed air from the compression cylinder and to deliver compressed air to the power cylinder for use in transmitting power to the crankshaft during engine operation; and valves selectively controlling gas flow into and out of the compression and power cylinders and the air reservoir such that the engine is operable in at least three modes, including an internal combustion engine (ICE) mode, an air compressor (AC) mode and a pre-compressed air power (PAP) mode, and wherein: in the ICE mode, the compression piston and power piston are in their respective compression and power modes, in that the compression piston draws in and compresses inlet air for use in the power cylinder, and compressed air is admitted to the power cylinder with fuel, at the beginning of an expansion stroke, which is ignited, burned and expanded on the same expansion stroke of the power piston, transmitting power to the crankshaft, and the combustion products are discharged on the exhaust stroke; in the AC mode, the compression piston is in the compression mode and draws in and compresses air which is stored in the reservoir for later use in the power cylinder; and in the PAP mode, the power piston is in the power mode and receives compressed air from the reservoir which is expanded on the expansion stroke of the power piston, transmitting power to the crankshaft, the expanded air is discharged on the exhaust stroke, and compressed air from the compression cylinder is not received in the air reservoir.