FUEL INJECTION NOZZLE FOR ENGINE USING TWO KINDS OF FUEL

PURPOSE:To simplify structure and avoid the need of a working oil piping by constituting the captioned device so that a valve body for fuel gas is operat ed by the high pressure fuel oil, not by working oil, in the captioned fuel injec tion nozzle having a valve body for fuel oil and the valve body for fuel gas. CONSTITUTION:Two valve chambers 2 and 3 are formed in parallel to a nozzle body 1, and the needle valves 3 and 8 for fuel oil and fuel gas which are urged towards the valve seats 5 and 10 installed in the pressure chambers 2a and 7a at the front edge of the valve chamber by coil springs 4 and 9 are installed in the valve chambers 2 and 3, respectively. A fuel oil passage 6 and fuel gas passage 11 for introducing the fuel oil and fuel gas into the pressure chambers 7a and 7b respectively are formed onto the nozzle body 1. The high pressure oil supplied from a plunger pump 16 is supplied into the fuel oil passage 6. In this case, step differences are formed onto the needle valve 8 for fuel gas, and a piston part 12 is formed, and the fuel oil passage 6 and the piston cham ber 7b faced to the step difference part of the piston part 12 are allowed to communicate through an introduced pressure passage 13.