Mechanical device fluid sealing mechanism and dynamic sealing fluid pressure control method

摘要

"FLUID SEALING MECHANISM FOR MECHANICAL DEVICE AND DYNAMIC FLUID PRESSURE CONTROL METHOD". A dynamic fluid sealing system for a fuel injection valve (180) employs sealing fluid to separate a gaseous fuel and a second fluid at the fuel injection valve, thereby preventing gaseous fuel leakage to the second. fluid. A pressure balancing system (100) including a pressure balancing device (110, 111) reduces the pressure differential between the sealing fluid and the gaseous fuel used in the injection valve. At the same time, the pressure balancing system dynamically balances the sealing fluid pressure such that the sealing fluid pressure is equal to or slightly greater than the gaseous fuel pressure within the injection valve. The pressure differential between gaseous fuel and sealing fluid may be maintained at the full operating range of engine speeds, engine loads and fuel shut-off conditions to prevent the escape of compressible gaseous fuel to the second fluid. . The reduced pressure differential between gaseous fuel and sealing fluid also reduces sealing fluid leakage to gaseous fuel.