Oil pump, engine cover and engine comprising the same

1. An oil pump, comprising:

a shell having an inlet and an outlet and defining a low-pressure oil chamber and a high-pressure oil chamber therein, the low-pressure oil chamber having a low-pressure oil passage connected to the inlet, and the high-pressure oil chamber having a high-pressure oil passage connected to the outlet, a partition wall being disposed between the low-pressure oil chamber and the high-pressure oil chamber for separating the low-pressure oil chamber and the high-pressure oil chamber;

a rotor mounting part on the shell and having a rotor supporting structure; and

a rotor mechanism disposed on the rotor mounting part,

wherein a buffer chamber is disposed between the partition wall and the low-pressure oil chamber, and a flow limiting wall is disposed in the buffer chamber,

wherein the flow limiting wall divides the buffer chamber into an inflowing buffer chamber and an outflowing buffer chamber connected to the inflowing buffer chamber via a pressure relief mechanism; and

wherein the partition wall comprises a main body portion adjacent to the outlet and an extending portion extending from the main body portion to the rotor mounting part, and a side of the extending portion of the partition wall located within the high-pressure oil chamber is tilted away from a corresponding portion of the shell defining an opposite side of the high-pressure oil chamber, defining a funnel-shaped portion of the high-pressure oil passage that gradually narrows towards the outlet so as to guide oil flow into the high-pressure oil chamber.

2. The oil pump according to claim 1 , wherein the rotor mounting part is disposed at an end of the shell, and the high-pressure oil chamber, the buffer chamber and the low-pressure oil chamber are located at the same side of the rotor mounting part.

3. The oil pump according to claim 1 , wherein one end of the flow limiting wall is connected to a lower portion of rotor mounting part, and the other end of the flow limiting wall is connected to the partition wall.

4. The oil pump according to claim 1 , further comprising a through hole connecting the inflowing buffer chamber and the outflowing buffer chamber formed in the flow limiting wall, and the pressure relief mechanism is disposed in the through hole.

5. The oil pump according to claim 1 , wherein a barrier wall is disposed between the outflowing buffer chamber and the low-pressure oil chamber.

6. The oil pump according to claim 5 , wherein the barrier wall is disposed at a side of the inlet and parallel to an inflowing direction of an oil flowing into the low-pressure oil chamber through the inlet.

7. The oil pump according to claim 5 , wherein a top end surface of the barrier wall is a circular arc surface.

8. An oil pump, comprising:

a shell having an inlet and an outlet and defining a low-pressure oil chamber and a high-pressure oil chamber therein, the low-pressure oil chamber having a low-pressure oil passage connected to the inlet, and the high-pressure oil chamber having a high-pressure oil passage connected to the outlet, a partition wall being disposed between the low-pressure oil chamber and the high-pressure oil chamber for separating the low-pressure oil chamber and the high-pressure oil chamber;

a rotor mounting part on the shell and having a rotor supporting structure; and

a rotor mechanism disposed on the rotor mounting part,

wherein the partition wall comprises a main body portion adjacent to the outlet and an extending portion extending from the main body portion to the rotor mounting part, and a side of the extending portion of the partition wall located within the high-pressure oil chamber is tilted away from a corresponding portion of the shell defining an opposite side of the high-pressure oil chamber, defining a funnel-shaped portion of the high-pressure oil passage that gradually narrows towards the outlet so as to guide oil flow into the high-pressure oil chamber, and

wherein the rotor mounting part is disposed at an end of the shell, and the high-pressure oil chamber and the low-pressure oil chamber are, side by side, located at the same side of a periphery of the rotor mounting part.

9. The oil pump according to claim 8 , wherein the shell comprises a main shell body and a cover coupled with the main shell body,

wherein the partition wall comprises a first partition wall portion formed on the cover, and a second partition wall portion formed on the main shell body, and having a fluid-tight contact with the first partition wall portion.

10. The oil pump according to claim 9 , wherein the first partition wall portion has a first smooth partition surface, and the second partition wall portion has a second smooth partition surface joined with the first smooth partition surface.

11. The oil pump according to claim 9 , wherein the partition wall has a bolt hole comprising a first bolt hole portion formed in the first partition wall portion, and a second bolt hole portion formed in the second partition wall portion and corresponding to the first bolt hole portion.

12. The oil pump according to claim 11 , wherein the bolt hole is formed at an end of the partition wall adjacent to the rotor mounting part.

13. The oil pump according to claim 11 , wherein a width of the extending portion of the partition wall is 1.5 to 2 times of a maximum value of a diameter of the bolt hole.

14. An engine cover, comprising:

an engine cover body, and

an oil pump disposed on the engine cover body, the oil pump further including:

a shell having an inlet and an outlet and defining a low-pressure oil chamber and a high-pressure oil chamber therein, the low-pressure oil chamber having a low-pressure oil passage connected to the inlet, and the high-pressure oil chamber having a high-pressure oil passage connected to the outlet, a partition wall being disposed between the low-pressure oil chamber and the high-pressure oil chamber for separating the low-pressure oil chamber and the high-pressure oil chamber;

a rotor mounting part on the shell and having a rotor supporting structure; and

a rotor mechanism disposed on the rotor mounting part,

wherein the shell of the oil pump is integral with the engine cover body,

wherein the partition wall comprises a main body portion adjacent to the outlet and an extending portion extending from the main body portion to the rotor mounting part, and a side of the extending portion of the partition wall located within the high-pressure oil chamber is tilted away from a corresponding portion of the shell defining an opposite side of the high-pressure oil chamber, defining a funnel-shaped portion of the high-pressure oil passage that gradually narrows towards the outlet so as to guide oil flow into the high-pressure oil chamber, and

wherein the rotor mounting part is disposed at an end of the shell, and the high-pressure oil chamber and the low-pressure oil chamber are located, side by side, at the same side of the rotor mounting part.

15. An engine comprising an engine cover according to claim 14 .