High-pressure fuel pump

Patent metadata

Field	Value
Publication number	US-9765739-B2
Application number	US-201414505886-A
Country	US
Kind code	B2
Filing date	Oct 3, 2014
Priority date	Oct 7, 2013
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A high-pressure fuel pump includes a pump housing, a pressurizing member, a suction valve seat, a suction valve body, and a suction valve chamber. The suction valve seat includes a first projected wall section that is projected to an upper side in a vertical direction. The pump housing includes a second projected wall section that is directed to the upper side in the vertical direction. A height of the lowest position in a portion of the second projected wall section that is projected to the upper side in the vertical direction is higher than a height of the lowest position in a portion of the first projected wall section that is projected to the upper side in the vertical direction. A first initial fuel pool is provided on an downstream side of the second projected wall section and on the upstream side of the suction valve seat.

First claim

What is claimed is:

1. A high-pressure fuel pump comprising:
a pump housing including a fuel passage;
a pressurizing member operably supported by the pump housing, so as to define a fuel pressurizing chamber for communicating with the fuel passage in the pump housing, the pressurizing member configured to be displaced in a suction operation direction in which fuel is suctioned into the fuel pressurizing chamber and in a discharge operation direction in which the fuel in the fuel pressurizing chamber is discharged;
a suction valve seat provided on a suction side of the fuel pressurizing chamber within the fuel passage, the suction valve seat including a first projected wall section that is projected towards an upper side in a vertical direction;
a suction valve body configured to engage with and disengage from the suction valve seat, so as to switch between a valve opened state in which a suction operation of the fuel into the fuel pressurizing chamber is permitted and a valve closed state in which a backflow of the fuel from the fuel pressurizing chamber to an upstream side of the suction valve seat is prevented; and
a suction valve chamber that houses the suction valve body on the suction side of the fuel pressurizing chamber within the fuel passage, wherein
the pump housing includes a second projected wall section that is projected towards the upper side in the vertical direction and provided inside of the suction valve chamber, the second projected wall section defines an opening, a height from a lowest position in a portion of the second projected wall section that is projected towards the upper side in the vertical direction is higher than a height from a lowest position in a portion of the first projected wall section that is projected towards the upper side in the vertical direction,
a fuel introducing chamber is provided between the second projected wall section and the suction valve seat and adjacent to the upstream side of the suction valve seat, the fuel from outside of the pump housing is configured to be directly introduced into the fuel introducing chamber,
the fuel introducing chamber, the first projected wall section and the second projected wall section provide a first initial fuel pool that stores the fuel when the fuel from the outside is introduced into the fuel introducing chamber and the suction valve body is in the valve closed state, and the first initial fuel pool is provided on a downstream side of the second projected wall section and on the upstream side of the suction valve seat.

2. The high-pressure fuel pump according to claim 1 , wherein
the fuel passage and the suction valve seat provide a second initial fuel pool that stores the fuel when the fuel from the outside is introduced into the fuel introducing chamber, the second initial fuel pool is provided on the downstream side of the suction valve seat in a portion of the fuel passage on the suction side.

3. The high-pressure fuel pump according to claim 1 , wherein
the fuel pressurizing chamber includes a suction port provided on the suction side of the fuel pressurizing chamber within the fuel passage, the suction port is provided on the downstream side of the suction valve seat,
a height of an opening inner circumferential surface of the suction port on the upper side in the vertical direction is set between the height of the first projected wall section and the height of the second projected wall section, and the height of the opening inner circumferential surface is closer to the height of the first projected wall section than the height of the second projected wall section.

4. The high-pressure fuel pump according claim 1 further comprising:
an elastic member configured to urge the suction valve body to one of the closing direction and the opening direction, the elastic member housed in the suction valve chamber;
a rod-shaped valve body operating member configured to urge the suction valve body to the other of the closing direction and the opening direction, the rod-shaped valve body operating member housed in the suction valve chamber, wherein
the second projected wall section is a flange that extends inwardly to define the opening, and the flange surrounds a shaft portion of the rod-shaped valve body operating member on the suction valve body side.

5. The high-pressure fuel pump according to claim 4 wherein
the suction valve chamber includes a cylindrical member that is fixed on the pump housing, the second projected wall section partitions the inside of the cylindrical member into a first inner chamber section on one side of the second projected wall section and a second inner chamber section on the other side of the second projected wall section, and the first inner chamber section houses the suction valve body and the fuel introducing chamber is arranged in the first inner chamber section.

6. The high-pressure fuel pump according to claim 5 wherein
the pump housing includes a fuel storage chamber for storing the fuel, and the cylindrical member includes a communication hole that communicates between the fuel storage chamber and the second inner chamber section on the upper side in the vertical direction.

7. The high-pressure fuel pump according to claim 5 wherein
the pump housing includes a cylinder member that slidably holds the pressurizing member and a holder member that holds the cylindrical member, the holder member coaxially joins the suction valve seat, a partition wall, and one end of the cylindrical member, the partition wall includes the second projected wall section.

8. The high-pressure fuel pump according to claim 2 , wherein
the fuel pressurizing chamber includes a suction port provided on the suction side of the fuel pressurizing chamber within the fuel passage, the suction port is provided on the downstream side of the suction valve seat,
a height of an opening inner circumferential surface of the suction port on the upper side in the vertical direction is set between the height of the first projected wall section the height of the second projected wall section, and the height of the opening inner circumferential surface is closer to the height of the first projected wall section than the height of the second projected wall section.

9. The high-pressure fuel pump according to claim 2 further comprising:
an elastic member configured to urge the suction valve body to one of the closing direction and the opening direction, the elastic member housed in the suction valve chamber;
a rod-shaped valve body operating member configured to urge the suction valve body to the other of the closing direction and the opening direction, the rod-shaped valve body operating member housed in the suction valve chamber, wherein
the second projected wall section is a flange that extends inwardly to define the opening, and the flange surrounds a shaft portion of the rod-shaped valve body operating member on the suction valve body side.

10. The high-pressure fuel pump according to claim 3 further comprising:
an elastic member configured to urge the suction valve body to one of the closing direction and the opening direction, the elastic member housed in the suction valve chamber;
a rod-shaped valve body operating member configured to urge the suction valve body to the other of the closing direction and the opening direction, the rod-shaped valve body operating member housed in the suction valve chamber, wherein
the second projected wall section is a flange that extends inwardly to define the opening, and the flange surrounds a shaft portion of the rod-shaped valve body operating member on the suction valve body side.

11. The high-pressure fuel pump according to claim 8 further co

Assignees

• Toyota Motor Co Ltd

Inventors

• Kato Yoshikazu

Classifications

• F02M59/447

  means specially adapted to limit fuel delivery or to supply excess of fuel temporarily, e.g. for starting of the engine (combined with fuel pump regulating devices F02D) · CPC title

• F02M59/367 Primary

  Pump inlet valves of the check valve type being open when actuated · CPC title

• F02M59/464

  Inlet valves of the check valve type · CPC title

• F02M2200/40

  Fuel-injection apparatus with fuel accumulators, e.g. a fuel injector having an integrated fuel accumulator · CPC title