GASEOUS AND LIQUID FUEL INJECTOR WITH A TWO-WAY HYDRAULIC FLUID CONTROL VALVE

A hydraulically actuated dual fuel injector (1) separately injects a gaseous fuel and a liquid fuel into a combustion chamber of an internal combustion engine. The injector comprises: (a) an injector body; (b) a hydraulic fluid inlet port (7) for a pressurized hydraulic fluid, said hydraulic fluid being of sufficient pressure to maintain sealing and to prevent leakage of the gaseous fuel into the hydraulic fluid; (c) a first liquid fuel inlet port (6) for a first liquid fuel; (d) a first injection valve (16) disposed within the injector body fluidly connected to the first fuel inlet port (6) for controlling injection of the first liquid fuel through a first fuel ejection port (5); (e) a second inlet port (23) for a second gaseous fuel; (f) a second injection valve (17) fluidly connected to the second inlet port (23) for controlling injection of the second gaseous fuel through a second fuel ejection port (4); (g) a first two-way control (3) valve which controls the flow of the hydraulic fluid to actuate the first injection valve (16); (h) a second control valve (2) which controls the flow of the hydraulic fluid to actuate the second injection valve (17); (i) a metering device (15) within the injector body for metering the amount of first liquid fuel inject ed by the first injection valve (16); and (j) a fluid seal cavity (22) in the injector body which prevents leakage of the second gaseou s fuel.