Abstract: A cam ring of a supply pump revolves around a camshaft without rotating. A tappet reciprocates in a direction perpendicular to the camshaft in response to revolution of the cam ring such that the tappet slides along a cam ring sliding surface. A plunger reciprocates together with the tappet to pressurize and deliver fuel. The cam ring sliding surface is shaped in a convex form that has a curved contour line which is non-circular. A height of an inside of the cam ring sliding surface is higher than a height of a periphery of the cam ring sliding surface. Specifically, an ellipsoidal surface portion is formed at the cam ring sliding surface, and an axial direction of a major axis of the ellipsoidal surface portion is set to coincide with a direction perpendicular to a sliding direction of the cam ring sliding surface.

Abstract: A cam ring of a supply pump revolves around a camshaft without rotating. A tappet reciprocates in a direction perpendicular to the camshaft in response to revolution of the cam ring such that the tappet slides along a cam ring sliding surface. A plunger reciprocates together with the tappet to pressurize and deliver fuel. The cam ring sliding surface is shaped in a convex form that has a curved contour line which is non-circular. A height of an inside of the cam ring sliding surface is higher than a height of a periphery of the cam ring sliding surface. Specifically, an ellipsoidal surface portion is formed at the cam ring sliding surface, and an axial direction of a major axis of the ellipsoidal surface portion is set to coincide with a direction perpendicular to a sliding direction of the cam ring sliding surface.

Abstract: A fuel injection valve includes a needle valve that controls communication between a high pressure chamber and an injection hole, a follower valve provided inside a control chamber controlled by fuel pressure inside an intermediate chamber, and an open-close valve that controls communication between a first passage and a low pressure passage and communication between a second passage and the low pressure passage. The fuel injection valve is configured to control the gradient of the fuel injection rate from the injection hole with an improved configuration.

Abstract: A fuel injection valve includes a needle valve that controls communication between a high pressure chamber and an injection hole, a follower valve provided inside a control chamber controlled by fuel pressure inside an intermediate chamber, and an open-close valve that controls communication between a first passage and a low pressure passage and communication between a second passage and the low pressure passage. The fuel injection valve is configured to control the gradient of the fuel injection rate from the injection hole with an improved configuration.

Abstract: A throttle portion is defined between an upper end of a sac chamber and a conical portion of a needle to have a throttle opening area S1. Half of an area surrounded by the throttle portion, the needle, an inner wall of the sac chamber, and a lower end extended line in a cross section of the sac chamber taken along a sac center line is an injection hole upstream area S2. A lift amount, when the throttle opening area S1 is equal to an area which is calculated by multiplying an injection hole area S3 by the number of the injection holes, is a predetermined lift amount L. A viscosity coefficient of fuel is ?. An index value Sa, which is calculated in accordance with an equation as below, is set to 0.5 or greater.

Abstract: A throttle portion is defined between an upper end of a sac chamber and a conical portion of a needle to have a throttle opening area S1. Half of an area surrounded by the throttle portion, the needle, an inner wall of the sac chamber, and a lower end extended line in a cross section of the sac chamber taken along a sac center line is an injection hole upstream area S2. A lift amount, when the throttle opening area S1 is equal to an area which is calculated by multiplying an injection hole area S3 by the number of the injection holes, is a predetermined lift amount L. A viscosity coefficient of fuel is ?. An index value Sa, which is calculated in accordance with an equation as below, is set to 0.5 or greater.

Abstract: A fuel injection valve includes a body including a first chamber that supplies fuel of a first pressure, a second chamber that supplies fuel of a second pressure, and an injection hole, a valve chamber member including a valve chamber connectable to the first chamber and the second chamber, a control chamber member including a control chamber connectable to the first chamber, a needle pressed by pressure of fuel in the control chamber in a direction that causes fuel injection from the injection hole to stop, an actuator, a valve element that selectively connects the first chamber, second chamber, and the valve chamber according to the actuator extending and contracting, and a transmission mechanism that when the actuator extends, transmits the force to the needle as a force in a direction that causes fuel to be injected from the injection hole.

Abstract: In a nozzle, in a cross section including an axis of a nozzle body, a side surface and a seat surface are both smoothly connected to an arc of a circle inscribing both the side surface and the seat surface. A part of a needle which is adjacent to a tip end side of a seat portion is a cone having a diameter reduced toward a tip end side of the cone in the axial direction. Thus, no corner is on the seat surface or the side surface, and the two surfaces form one curved surface. Since a cavitation generated in a sack chamber can be reduced, even when an injection quantity is significantly small such that an injection port does not throttle an injection flow, a flow coefficient of the injection flow is improved and a penetration of a spray of the fuel can be maintained.

Abstract: A fuel injection valve includes a body including a first chamber that supplies fuel of a first pressure, a second chamber that supplies fuel of a second pressure, and an injection hole, a valve chamber member including a valve chamber connectable to the first chamber and the second chamber, a control chamber member including a control chamber connectable to the first chamber, a needle pressed by pressure of fuel in the control chamber in a direction that causes fuel injection from the injection hole to stop, an actuator, a valve element that selectively connects the first chamber, second chamber, and the valve chamber according to the actuator extending and contracting, and a transmission mechanism that when the actuator extends, transmits the force to the needle as a force in a direction that causes fuel to be injected from the injection hole.

Abstract: In a nozzle, in a cross section including an axis of a nozzle body, a side surface and a seat surface are both smoothly connected to an arc of a circle inscribing both the side surface and the seat surface. A part of a needle which is adjacent to a tip end side of a seat portion is a cone having a diameter reduced toward a tip end side of the cone in the axial direction. Thus, no corner is on the seat surface or the side surface, and the two surfaces form one curved surface. Since a cavitation generated in a sack chamber can be reduced, even when an injection quantity is significantly small such that an injection port does not throttle an injection flow, a flow coefficient of the injection flow is improved and a penetration of a spray of the fuel can be maintained.