Patent ID: 6711944
Filing Date: 2004-03-30
Classification: F02B,G01M

Abstract:
A method of testing an engine including a cylinder, a piston, a crank shaft, an intake valve and an exhaust valve, comprising the steps of:rotating the crank shaft using an external power source and thereby reciprocating the piston in the cylinder while at least one of (i) an external intake-valve side space communicating with the intake valve and not supplied with pressurized air and depressurized air from outside the engine and (ii) an external exhaust-valve side space communicating with the exhaust valve and not supplied with pressurized air and depressurized air from outside the engine is isolated from an atmosphere, continuously measuring, while the crank shaft is rotated, a pressure in said at least one of the intake-valve side and exhaust-valve side spares that is isolated from the atmosphere, determining, based on the continuously measured pressure, at least one of (a) a pressure occurring to said at least one of the intake-valve side and exhaust-valve side spaces, when at least one of the corresponding intake and exhaust valves is closed, and (b) at least one of a starting and an ending timing of a closed state of at least one of the corresponding intake and exhaust valves, and evaluating a state of the engine based on the determined at least one of (a) the pressure in said at least one of the intake-valve side and exhaust-valve side spaces and (b) the at least one of the starting and ending timings of the closed state of the at least one of the corresponding intake and exhaust valves.