Fuel injection valve

A fuel injection valve comprising:

• a nozzle portion having a nozzle hole to inject fuel and a valve seat formed around the nozzle hole;
• a housing that is cylindrical and connected to an opposite side of the nozzle portion from the nozzle hole;
• a needle configured to separate from and abut on the valve seat at one end to open and close the nozzle hole;
• a movable core provided to the needle;
• a fixed core that is cylindrical and provided on an opposite side of the movable core from the nozzle hole, the fixed core being at least partially positioned radially inside the housing at a part in an axial direction;
• a coil provided between the fixed core and the housing and configured to, when energized, attract the movable core with the needle toward the fixed core;
• and
• an upper housing provided between the fixed core and the housing and positioned on an opposite side of the coil from the nozzle hole, the upper housing configured to form a magnetic circuit with the fixed core and the housing, wherein
• the upper housing has a first tapered surface and a first cylindrical surface,
• the first tapered surface is formed on one of outer and inner peripheral walls,
• the first cylindrical surface is formed on an other of the outer and inner peripheral walls,
• one of the housing and the fixed core has a second tapered surface that radially faces the first tapered surface,
• an other of the housing and the fixed core has a second cylindrical surface that radially faces the first cylindrical surface,
• the second cylindrical surface is formed on the housing,
• the second tapered surface is formed on the fixed core,
• each of the first tapered surface and the second tapered surface is tapered, such that a diameter thereof reduces from a side of the nozzle hole toward an opposite side of the nozzle hole, and
• the upper housing is made of a magnetic material in an annular shape or a C-shape.

A fuel injection valve comprising:

• a nozzle portion having a nozzle hole to inject fuel and a valve seat formed around the nozzle hole;
• a housing that is cylindrical and connected to an opposite side of the nozzle portion from the nozzle hole;
• a needle configured to separate from and abut on the valve seat at one end to open and close the nozzle hole;
• a movable core provided to the needle;
• a fixed core that is cylindrical and provided on an opposite side of the movable core from the nozzle hole, the fixed core being at least partially positioned radially inside the housing at a part in an axial direction;
• a coil provided between the fixed core and the housing and configured to, when energized, attract the movable core with the needle toward the fixed core;
• and
• an upper housing provided between the fixed core and the housing and provided on an opposite side of the coil from the nozzle hole, the upper housing configured to form a magnetic circuit with the fixed core and the housing, wherein
• the upper housing includes
• an inner member and
• an outer member provided radially outside the inner member, the inner member has
• a first tapered surface formed on an outer peripheral wall and
• a first cylindrical surface formed on an inner peripheral wall,
• the outer member has
• a second tapered surface formed on the inner peripheral wall to radially face the first tapered surface and
• a second cylindrical surface formed on the outer peripheral wall,
• the fixed core has a third cylindrical surface that radially faces the first cylindrical surface,
• the housing has a fourth cylindrical surface that radially faces the second cylindrical surface, and
• the upper housing is made of a magnetic material in an annular shape or a C-shape.

A fuel injection valve comprising:

• a nozzle portion having a nozzle hole to inject fuel and a valve seat formed around the nozzle hole;
• a housing that is cylindrical and connected to an opposite side of the nozzle portion from the nozzle hole;
• a needle configured to separate from and abut on the valve seat at one end to open and close the nozzle hole;
• a movable core provided to the needle;
• a fixed core that is cylindrical and provided on an opposite side of the movable core from the nozzle hole, the fixed core being at least partially positioned radially inside the housing at a part in an axial direction;
• a coil provided between the fixed core and the housing and configured to, when energized, attract the movable core with the needle toward the fixed core;
• and
• an upper housing provided between the fixed core and the housing and provided on an opposite side of the coil from the nozzle hole, the upper housing configured to form a magnetic circuit with the fixed core and the housing, wherein
• the upper housing includes a bottom portion, an inward extended portion, and an outward extended portion,
• the inward extended portion is formed to extend from an inner edge portion of the bottom portion in the axial direction of the bottom portion,
• the outward extended portion is formed to extend from an outer edge portion of the bottom portion in the axial direction of the bottom portion, and
• the upper housing is made of a magnetic material in an annular shape or a C-shape.