Patent ID: 11879455
Assignee: DENSO CORPORATION
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 0:
1. A supply pump comprising:
a camshaft that is configured to be rotated;
a cam that is eccentric to the camshaft and is configured to rotate integrally with the camshaft;
a cam ring that is configured to revolve around the camshaft without rotating while the cam ring slides along an outer periphery of the cam;
a tappet that is configured to reciprocate 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 which is an outer peripheral surface of the cam ring that extends in a direction parallel with the camshaft; and
a plunger that is configured to reciprocate together with the tappet to pressurize and deliver fluid, wherein:
the tappet has a tappet recess formed at a tappet sliding surface which is opposed to the cam ring sliding surface, wherein the tappet recess is out of contact with the cam ring sliding surface;
the cam ring sliding surface is shaped in a convex form while a contour line of the convex form is a closed curve that is other than a circle, wherein 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;
an ellipsoidal surface portion is formed at the cam ring sliding surface such that an axial direction of a major axis of the ellipsoidal surface portion is set to coincide with one of a sliding direction of the cam ring sliding surface and a direction perpendicular to the sliding direction, and an axial direction of a minor axis of the ellipsoidal surface portion is set to coincide with another one of the sliding direction and the direction perpendicular to the sliding direction; and
with respect to a projection height of an apex of the ellipsoidal surface portion measured from a location, at which two opposite end points of an ellipsoidal surface of the ellipsoidal surface portion are located, to the apex in a cross-section which extends through the apex and is parallel with an axis of the plunger, the measured projection height of the apex along a plane extending in the sliding direction of the cam ring sliding surface is higher than the measured projection height of the apex along a plane extending in the direction perpendicular to the sliding direction.