Plunger pump

Patent metadata

Field	Value
Publication number	US-10907597-B2
Application number	US-201916364702-A
Country	US
Kind code	B2
Filing date	Mar 26, 2019
Priority date	Mar 28, 2018
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

This plunger pump includes a pressurization chamber that has a tubular inner circumferential wall and a plunger that has a substantially cylindrical outer circumferential surface. The inner circumferential wall has, in a part thereof in a circumferential direction about an axis of the plunger, a suction opening, which communicates with the pressurization chamber and is for introducing a fuel into the pressurization chamber. The inner circumferential wall is formed with an enlarged gap portion having a larger dimension than a dimension, at a position of the suction opening, from the outer circumferential surface of the plunger to an inner circumferential surface of the inner circumferential wall along a radial direction of the plunger, in at least a part of the inner circumferential wall at a position away from the position of the suction opening in the circumferential direction.

First claim

What is claimed is:

1. A plunger pump comprising:
a pressurization chamber that has a tubular inner circumferential wall; and
a plunger that has a substantially cylindrical outer circumferential surface and is held by a guide portion so as to freely slide along an extending direction of the inner circumferential wall,
wherein the inner circumferential wall has, in a part thereof in a circumferential direction about an axis of the plunger, a suction opening, which communicates with the pressurization chamber and is for introducing a fuel into the pressurization chamber, and
wherein the inner circumferential wall is formed with an enlarged gap portion having larger dimension than a dimension, at a position of the suction opening, from the outer circumferential surface of the plunger to an inner circumferential surface of the inner circumferential wall along a radial direction of the plunger, in at least a part of the inner circumferential wall at a position away from the position of the suction opening in the circumferential direction
wherein a discharge opening for discharging the fuel from the pressurization chamber is provided in the inner circumferential wall and
wherein the enlarged gap portion is provided in a region closer to the discharge opening in the circumferential direction than to the suction opening;
wherein a sectional shape of the inner circumferential wall, which is orthogonal to the axis of the plunger, is
a circular shape, and the axis of the plunger is disposed to be eccentric to a center of the circular shape toward a suction opening side; or,
an elliptical shape, and the suction opening and the discharge opening are provided in the inner circumferential wall on a minor axis side, and an interval between the inner circumferential wall on a major axis side of the elliptical shape and the outer circumferential surface of the plunger is the enlarged gap portion.

Assignees

• Keihin Corp

Inventors

• Ogane Yuya

Classifications

• F02M59/368

  Pump inlet valves being closed when actuated · CPC title

• F04B1/0439

  Supporting or guiding means for the pistons · CPC title

• F02M59/02 Primary

  of reciprocating-piston {or reciprocating-cylinder} type · CPC title

• F04B11/0016

  with a fluid spring · CPC title

• F02M59/442

  means preventing fuel leakage around pump plunger, e.g. fluid barriers · CPC title