PURPOSE: To provide a simple structure, secure operation, and stable fuel flow rate by tilting a jet needle.
CONSTITUTION: A jet needle 10 is inserted and supported in a needle insertion hole 14 on a bottom wall 16b of a cup-shaped throttle valve 16. A pressing plate 8 which prevents knocking-up of the jet needle 10 is superposed on the bottom wall 16b of the throttle valve 16. An elastic pressing piece 9 which hangs over the upper side of the needle insertion hole 14 is connected with the pressing plate 8. The elastic pressing piece 9 is elastically engaged with a peripheral face of a head section 10a of the jet needle 10 which protrudes upward from the bottom wall 16b of the throttle valve 16, and the jet needle 10 is pushed down in the nearly vertical direction to its axial line. A tapered lower end section of the jet needle 10 ascends and descends always in contact with one side of an inner peripheral wall of a needle jet 21a.
KUROKI NOBUYUKI