Valve system of vehicle fuel pump

Patent metadata

Field	Value
Publication number	US-11708797-B2
Application number	US-202017103167-A
Country	US
Kind code	B2
Filing date	Nov 24, 2020
Priority date	Mar 23, 2020
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

A valve system of a vehicle fuel pump includes: a reservoir cup disposed within a fuel tank storing fuel in the reservoir cup; a fuel pump configured to pump fuel from the reservoir cup to the engine while supplying fuel to a jet pump through a first discharge port; a jet pump configured to charge the reservoir cup with fuel by drawing fuel from the fuel tank by using a pressure of fuel supplied by the fuel pump; and a jet pump control valve disposed on the first discharge port and configured to control a flow of fuel discharged from the fuel pump to the jet pump.

First claim

What is claimed is:

1. A valve system of a vehicle fuel pump, the valve system comprising:
a reservoir cup disposed within a fuel tank storing fuel in the reservoir cup;
a fuel pump configured to pump fuel from the reservoir cup to an engine while supplying fuel to a jet pump through a first discharge port of the fuel pump;
the jet pump configured to charge the reservoir cup with fuel by drawing fuel from the fuel tank by using a pressure of fuel supplied by the fuel pump; and
a jet pump control valve disposed on the first discharge port and configured to control a flow of fuel discharged from the fuel pump to the jet pump,
wherein, when the engine is on and a pressure of fuel discharged from the fuel pump to the engine is increased to reach a first set pressure, the jet pump control valve opens a jet pump flow path connecting the jet pump and the first discharge port of the fuel pump, and maintains the jet pump flow path in a closed state before reaching the first set pressure, and
wherein, when the engine is off and the pressure of fuel discharged from the fuel pump to the jet pump is reduced to reach a second set pressure determined to be smaller than the first set pressure, the jet pump control valve closes the jet pump flow path, and maintains the open jet pump flow path when the pressure of fuel discharged from the fuel pump to the jet pump is at a pressure value between the first set pressure and the second set pressure,
wherein the jet pump control valve comprises:
a first valve housing, in which a plunger lift path having a predetermined height is defined, wherein the jet pump flow path is configured to be connected to a middle position of the plunger lift path;
a plunger disposed on the plunger lift path in a liftable manner so as to open and close the jet pump flow path depending on a position on the plunger lift path;
a second valve housing, in which a piston lift path having a predetermined height is defined, having an open hole defined on a first sidewall portion of the second valve housing;
a piston disposed on the piston lift path in a liftable manner and configured to be integrally connected to the plunger via a lift bar;
an elastic member arranged between a bottom surface of a top end of the second valve housing and a top surface of the piston, the elastic member configured to be compressed when the plunger moves upwards; and
a foldable leaf spring disposed on the top surface of the piston and arranged between the piston and the elastic member, and configured to restrain the jet pump flow path from being opened by a pressure of fuel smaller than the first set pressure when the engine is on.

2. The valve system according to claim 1 , wherein the foldable leaf spring comprises:
a horizontal leaf spring portion disposed in the piston lift path to extend in a direction perpendicular to a direction in which the piston is configured to be lifted up and down, with the elastic member being disposed on a top surface of the horizontal leaf spring portion;
a vertical leaf spring portion configured to be attached to a first end of the horizontal leaf spring portion and disposed in the piston lift path in the direction in which the piston is lifted up and down, with a bottom end of the vertical leaf spring portion being fixedly disposed on the top surface of the piston; and
a folding leaf spring portion configured to be integrally disposed on a second end portion of the horizontal leaf spring portion in a foldable manner and disposed in the piston lift path to extend in the direction in which the piston is lifted up and down, with a flange being integrally disposed on a bottom end of the folding leaf spring portion to extend through and held by the open hole.

3. The valve system according to claim 2 , wherein, when the folding leaf spring portion pivots toward a bottom surface of the vertical leaf spring portion about a second end portion of the horizontal leaf spring portion due to a pressure of fuel applied to the plunger by the fuel pump, the plunger is released and detached from the open hole and is configured to move upwards in the plunger lift path in a direction of opening the jet pump flow path.

4. The valve system according to claim 2 , wherein the foldable leaf spring further comprises an inner spring arranged between the vertical leaf spring portion and the folding leaf spring portion, the inner spring being configured to be compressed when the folding leaf spring portion pivots toward the bottom surface of the vertical leaf spring portion.

5. The valve system according to claim 3 , wherein the first set pressure is a value obtained by adding a pressure of fuel for compressive deformation of the elastic member and a pressure of fuel for folding deformation of the foldable leaf spring.

6. The valve system according to claim 2 , wherein the plunger lift path comprises:
an upper lift path in which the plunger is located to open the jet pump flow path; and
a lower lift path in which the plunger is located to close the jet pump flow path.

7. The valve system according to claim 6 , wherein, when the pressure of fuel discharged to the jet pump at start of the engine is equal to or greater than the first set pressure, the jet pump control valve causes the flange of the foldable leaf spring to be detached and released from the open hole and the plunger to be located in the upper lift path so that the jet pump flow path is opened.

8. The valve system according to claim 6 , wherein, when the pressure of fuel discharged to the jet pump at start of the engine is smaller than the first set pressure, the jet pump control valve causes the flange of the foldable leaf spring to be located in and held by the open hole and the plunger to be located in the lower lift path so that the jet pump flow path remains in a closed position.

9. The valve system according to claim 6 , wherein, when the pressure of fuel discharged to the jet pump is reduced to be smaller than the first set pressure and is greater than the second set pressure after the jet pump path is opened, the jet pump control valve causes the flange of the foldable leaf spring to remain released from the open hole and the plunger to remain in the upper lift path so that the jet pump flow path remains in an opened position.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Kim Keun Soo
• Park Jung Hoon
• Kim Dong Hyun

Classifications

• F02D1/16 Primary

  Adjustment of injection timing (F02D1/02 takes precedence) · CPC title

• F02D1/06

  by means dependent on pressure of engine working fluid (F02D1/08 takes precedence) · CPC title

• F02D2001/0005

  Details, component parts or accessories of centrifugal governors · CPC title

• F02D2200/0602

  Fuel pressure · CPC title

• F02M37/025

  Feeding by means of a liquid fuel-driven jet pump (jet pumps per se F04F) · CPC title