Fuel injection valve
A fuel injection valve includes a nozzle body and a plate. The nozzle body includes an injection orifice, through which fuel is injected, a needle that controls the injection through the injection orifice, and a needle-receiving bore that receives the needle. The plate is adjacently provided to the nozzle body for defining a fuel passage therein, through which fuel is supplied to the needle-receiving bore. The plate has an annular groove, which connects the fuel passage with the needle-receiving bore, at an end surface of the plate toward the nozzle body.
1. A fuel injection valve comprising:
a nozzle body that includes:
an injection orifice, through which fuel is injected;
a needle that controls the injection through the injection orifice; and
a needle-receiving bore that receives the needle, the needle-receiving bore being connected with the injection orifice; and
a plate that is adjacently provided to the nozzle body, said plate having a nozzle body-side end surface directly contacting a plate-side end surface of said nozzle body, said plate having a fuel passage therein, through which fuel is supplied to the needle-receiving bore, wherein the plate has an annular groove defined in said nozzle body-side end surface thereof which directly connects the fuel passage with the needle-receiving bore, wherein the annular groove opens to the needle-receiving bore, wherein:
the annular groove has a radially outer peripheral wall which is located radially outward of an inner wall of the needle-receiving bore that defines an opening portion of said needle-receiving bore at said plate-side end surface of said nozzle body.
2. The fuel injection valve according to claim 1 , further comprising:
a cylinder that is provided adjacently to the plate, in the needle-receiving bore, the cylinder defining a hollow, in which the needle slides, wherein:
the cylinder divides the needle-receiving bore into an annular passage, which communicates with the annular groove, and a high-pressure chamber, which communicates with the injection orifice, such that a smallest gap between an outer peripheral wall of the cylinder and an opposing inner wall of the needle-receiving bore opposing the outer peripheral wall forms a boundary between the annular passage and the high-pressure chamber; and
the annular groove has a width and a depth such that a sum of an area of a cross section of the annular passage in a circumferential direction and an area of a cross section of the annular groove in the circumferential direction is equal to or more than ½ of an area of a passage cross section of the fuel passage.
3. The fuel injection valve according to claim 1 , wherein:
the nozzle body includes one of a pin groove and a pin hole, which engages with a pin that positions the nozzle body relative to the plate in a circumferential direction; and
the one of the pin groove and the pin hole is displaced from the annular groove in a radial direction.
4. The fuel injection valve according to claim 1 , wherein:
the annular groove has a width equal to or greater than a passage diameter of the fuel passage.
5. The fuel injection valve according to claim 1 , wherein:
the plate includes a recess at the end surface of the plate facing toward the nozzle body; and
the recess is displaced from the annular groove in a radial direction.
6. The fuel injection valve according to claim 1 , wherein:
the plate is fixed with respect to the nozzle body.
7. The fuel injection valve according to claim 6 , wherein the plate is fixed to the nozzle body by means of a threaded retaining nut.
8. The fuel injection valve according to claim 1 , wherein:
fuel flows into the needle-receiving bore only through a combination of the fuel passage and the annular groove.
9. The fuel injection valve according to claim 1 , wherein:
the needle is confined to the needle-receiving bore of the nozzle body so that the needle does not penetrate a plane of the plate.
10. The fuel injection valve according to claim 1 , further comprising:
a spring that is received in the needle-receiving bore of the nozzle body, wherein the spring biases the nozzle toward the injection orifice, wherein the spring is confined to the needle-receiving bore.
11. A fuel injection valve comprising:
a nozzle body that includes:
an injection orifice, through which fuel is injected;
a needle that controls the injection through the injection orifice; and
a needle-receiving bore that receives the needle, the needle-receiving bore being connected with the injection orifice; and
a plate that is adjacently provided to the nozzle body, said plate having a fuel passage therein, through which fuel is supplied to the needle-receiving bore, wherein:
the plate has a groove, which directly connects the fuel passage with the needle-receiving bore, at a nozzle body-side end surface of the plate facing toward and directly contacting a plate-side end surface of the nozzle body; and
the groove has a length in a circumferential direction and a width such that an area of an overlapping section between the needle-receiving bore and an opening portion of the groove is equal to or greater than an area of a passage cross section of the fuel passage, wherein the groove opens to the needle-receiving bore, wherein:
the annular groove has a radially outer peripheral wall which is located radially outward of an inner wall of the needle-receiving bore that defines an opening portion of said needle-receiving bore at said plate-side end surface of said nozzle body.
12. The fuel injection valve according to claim 11 , wherein:
the overlapping section is a communicating section, through which the needle-receiving bore communicates with the opening portion of the groove.
13. The fuel injection valve according to claim 11 , wherein:
the plate is fixed with respect to the nozzle body.
14. The fuel injection valve according to claim 13 , wherein the plate is fixed to the nozzle body by means of a threaded retaining nut.
15. The fuel injection valve according to claim 11 , wherein:
fuel flows into the needle-receiving bore only through a combination of the fuel passage and the annular groove.
16. The fuel injection valve according to claim 11 , wherein:
the needle is confined to the needle-receiving bore of the nozzle body so that the needle does not penetrate a plane of the plate.
17. The fuel injection valve according to claim 11 , further comprising:
a spring that is received in the needle-receiving bore of the nozzle body, wherein the spring biases the nozzle toward the injection orifice, wherein the spring is confined to the needle-receiving bore.