Fuel injection device

A fuel injection device that opens and closes a valve portion for controlling an injection of supply fuel supplied from a supply channel and injected from a nozzle hole, and that discharges a portion of the supply fuel into a return channel based on the control, the fuel injection device comprising:

• a control body having a pressure control chamber, into which the fuel flowing through the supply channel flows from an inflow port and from which the fuel is discharged to the return channel through an outflow port, and an opening wall surface exposed to the pressure control chamber and having the inflow port and the outflow port opened therein;
• a pressure control valve configured to make communication between the outflow port and the return channel and to interrupt the communication, so as to control pressure of the fuel in the pressure control chamber;
• a valve member configured to open and close the valve portion in response to the pressure of the fuel in the pressure control chamber;
• and
• a pressing member arranged to be reciprocally displaced in the pressure control chamber and having a pressing surface opposite to the opening wall surface, wherein the pressing surface of the pressing member presses the opening wall surface to interrupt communication between the inflow port and the pressure control chamber when the communication between the outflow port and the return channel is made by the pressure control valve,
• the pressing surface of the pressing member is displaced and separated from the opening wall surface to open the inflow port of the opening wall surface to the pressure control chamber when the communication between the outflow port and the return channel is interrupted by the pressure control valve,
• the opening wall surface has an outflow peripheral surface portion provided around the outflow port, and an inflow peripheral surface portion provided around the inflow port,
• the pressing surface of the pressing member is provided with an outflow-opposite surface portion opposite to the outflow peripheral surface portion in a displacement axis direction, and an inflow-opposite surface portion opposite to the inflow peripheral surface portion in the displacement axis direction,
• one of the outflow peripheral surface portion and the outflow-opposite surface portion of the opening wall surface and the pressing surface is provided with an outflow depressed portion with a depressed outflow bottom surface depressed in the displacement axis direction to a side opposite to the other one of the outflow peripheral surface portion and the outflow-opposite surface portion,
• one of the inflow peripheral surface portion and the inflow-opposite surface portion of the opening wall surface and the pressing surface, which is provided with the outflow depressed portion, is provided with an inflow depressed portion with a depressed inflow bottom surface depressed in the displacement axis direction to a side opposite to the other one of the inflow peripheral surface portion and the inflow-opposite surface portion,
• a depressed dimension of the inflow depressed portion is larger than a depressed dimension of the outflow depressed portion, in the displacement axis direction,
• the inflow port is open at the depressed inflow bottom surface of the inflow depressed portion, and
• the dimension of the inflow depressed portion in a radial direction of the pressing member is larger than a diameter of the inflow port.