Engine that includes blow-by-gas returning system

Patent metadata

Field	Value
Publication number	US-10982576-B2
Application number	US-201916410280-A
Country	US
Kind code	B2
Filing date	May 13, 2019
Priority date	May 14, 2018
Publication date	Apr 20, 2021
Grant date	Apr 20, 2021

Abstract

In an engine that includes a blow-by-gas returning system configured to direct blow-by gas within a crankcase to an intake system through an inside of a head cover, the intake system includes a cover intake-passage disposed at a blow-by-gas outlet of the head cover, and the cover intake-passage communicates with a blow-by-gas passage of the blow-by-gas outlet.

First claim

What is claimed is:

1. An engine that includes a blow-by-gas returning system, the engine being configured to direct blow-by gas within a crankcase to an intake system through an inside of a head cover,
wherein the intake system includes a cover intake-passage disposed at the head cover, and the cover intake-passage communicates with a blow-by-gas passage of the head cover,
wherein the cover intake-passage forms part of a suction passage that connects an air cleaner with a supercharger, and the cover intake-passage is integral with the head cover, and
wherein the blow-by-gas passage communicates with the cover intake-passage through a communication hole of a gasket, the gasket being held between the blow-by-gas passage and the cover intake-passage.

2. The engine that includes the blow-by-gas returning system according to claim 1 , wherein the cover intake-passage is a curved passage.

3. The engine that includes the blow-by-gas returning system according to claim 2 , wherein a terminating passage of the cover intake-passage is nearer to an edge of the head cover in a longitudinal direction of the head cover than a leading passage of the cover intake-passage is.

4. The engine that includes the blow-by-gas returning system according to claim 3 , wherein the cover intake-passage includes the leading passage and the terminating passage that are parallel to each other, and both extend in a direction that crosses over the longitudinal direction of the head cover, and an intermediate passage that connects a terminating end of the leading passage with a leading end of the terminating passage.

5. An engine that includes a blow-by-gas returning system, the engine being configured to direct blow-by gas within a crankcase to an intake system through an inside of a head cover,
wherein the intake system includes a cover intake-passage disposed at the head cover, and the cover intake-passage communicates with a blow-by-gas passage of the head cover,
the cover intake-passage forms part of a suction passage that connects an air cleaner with a supercharger, and the cover intake-passage is integral with the head cover,
a bottom wall of the blow-by-gas passage includes a return hole through which oil collected within the blow-by-gas passage drops,
the bottom wall includes a descending slope that is around the return hole and becomes lower toward the return hole, and
the blow-by-gas passage communicates with the cover intake-passage through a communication hole of a gasket, the gasket being held between the blow-by-gas passage and the cover intake-passage.

6. The engine that includes the blow-by-gas returning system according to claim 5 , the engine further comprising a return check-valve that allows oil to drop through the return hole, and does not allow reverse flow from the return hole to the blow-by-gas passage.

7. The engine that includes the blow-by-gas returning system according to claim 6 , wherein a valve actuator is disposed under the return hole.

8. The engine that includes the blow-by-gas returning system according to claim 7 , wherein the return check-valve is a reed valve, and a valve seat of the reed valve is coated with an elastic material, or a valve-body end that is part of a valve body and is to be brought into contact with the valve seat is coated with the elastic material.

9. The engine that includes the blow-by-gas returning system according to claim 6 , wherein the return check-valve is a reed valve, and a valve seat of the reed valve is coated with an elastic material, or a valve-body end that is part of a valve body and is to be brought into contact with the valve seat is coated with the elastic material.

10. The engine that includes the blow-by-gas returning system according to claim 6 , wherein the cover intake-passage is disposed at a blow-by-gas outlet of the head cover, and
the bottom wall is a bottom wall of the blow-by-gas outlet.

11. The engine that includes the blow-by-gas returning system according to claim 10 , wherein a discharge check-valve is disposed on the bottom wall, the discharge check-valve allows blow-by gas to flow into the blow-by-gas outlet and does not allow blow-by gas to flow from the blow-by-gas outlet, and
the discharge check-valve is between a pair of the return check-valves.

12. The engine that includes the blow-by-gas returning system according to claim 5 , wherein a valve actuator is disposed under the return hole.

13. The engine that includes the blow-by-gas returning system according to claim 12 , wherein the return check-valve is a reed valve, and a valve seat of the reed valve is coated with an elastic material, or a valve-body end that is part of a valve body and is to be brought into contact with the valve seat is coated with the elastic material.

14. The engine that includes the blow-by-gas returning system according to claim 5 , wherein the return check-valve is a reed valve, and a valve seat of the reed valve is coated with an elastic material, or a valve-body end that is part of a valve body and is to be brought into contact with the valve seat is coated with the elastic material.
2020.

15. The engine that includes the blow-by-gas returning system according to claim 5 , wherein the cover intake-passage is disposed at a blow-by-gas outlet of the head cover, and
the bottom wall is a bottom wall of the blow-by-gas outlet.

16. The engine that includes the blow-by-gas returning system according to claim 15 , wherein a discharge check-valve is disposed on the bottom wall, the discharge check-valve allows blow-by gas to flow into the blow-by-gas outlet and does not allow blow-by gas to flow from the blow-by-gas outlet, and
the discharge check-valve is between a pair of the return check-valves.

Assignees

• Kubota Kk

Inventors

• Oso Hiroki
• Tanaka Akira
• Koyama Hideyuki
• Kaneko Rina
• Okada Nobuyoshi

Classifications

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02M35/10222

  Exhaust gas recirculation [EGR]; Positive crankcase ventilation [PCV]; Additional air admission, lubricant or fuel vapour admission · CPC title

• F01M2013/0494

  using check valves · CPC title

• F02M35/10091

  characterised by details of intake ducts: shapes; connections; arrangements (ducts within or on the plenum chamber F02M35/10039) · CPC title

• F01M13/0416

  arranged in valve-covers · CPC title