Intake device of engine

Patent metadata

Field	Value
Publication number	US-2016281633-A1
Application number	US-201615074034-A
Country	US
Kind code	A1
Filing date	Mar 18, 2016
Priority date	Mar 24, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

An intake device of an engine having cylinders is provided. The intake device includes a cylinder head formed with two intake ports per cylinder, and a forced induction system. One of the two intake ports is designed to have a smaller passage cross-sectional area at a throat portion thereof than that of the other intake port, and to cause a strength of a tumble flow strength of intake air formed within a combustion chamber to be stronger when a flow of the intake air into the combustion chamber is assumed to be caused only from the one of the two intake ports, than only from the other intake port. A tumble ratio of the intake air flow within the combustion chamber is a predetermined value or greater when the intake air is forcibly induced and flows into the combustion chamber from the two intake ports.

First claim

What is claimed is:

1 . An intake device of an engine having one or more cylinders, the intake device comprising:
a cylinder head formed with two intake ports per cylinder for flowing intake air into a combustion chamber of the cylinder; and a forced induction system for forcibly inducing the intake air, wherein the two intake ports have respective throat portions, and in each cylinder, one of the two intake ports is designed to have a smaller passage cross-sectional area at its throat portion than a passage cross-sectional area of the throat portion of the other intake port, and to cause a strength of a tumble flow of intake air formed within the combustion chamber when a flow of the intake air into the combustion chamber is assumed to be only from the one of the two intake ports, to be stronger than a strength of a tumble flow of intake air formed within the combustion chamber when the flow of the intake air into the combustion chamber is assumed to be only from the other intake port, and wherein a tumble ratio of a flow of the intake air within the combustion chamber is a predetermined value or greater when the intake air is forcibly induced by the forced induction system and flows into the combustion chamber from the two intake ports within an operating range of the engine where the forced induction is performed.

2 . The intake device of claim 1 , wherein the predetermined value is 2.

3 . The intake device of claim 1 , wherein when seen in a center axis direction of each cylinder, the two intake ports of the cylinder extend to the combustion chamber in a first direction intersecting the center axis direction, and when seen in a second direction perpendicular to the center axis direction and the first direction, the two intake ports extend on an upper side of the combustion chamber while inclining to a combustion chamber side in the center axis direction, and open to the combustion chamber at opening portions of the intake ports, respectively, the opening portions located in a part of a surface of the cylinder head facing the combustion chamber, on an opposite side from the first direction,
wherein in the cylinder head, an intake valve seat having a substantially ring shape and having a sealing surface on an inward side in a radial direction of the intake valve seat, is attached to the opening portion of the one of the intake ports, and when seen in the second direction, a part of a wall surface of the throat portion of the one of the intake ports has a shape for guiding intake air flowing near the part of the wall surface, to flow substantially straight toward an area that is on the radially inward side of the sealing surface and near a part of the sealing surface located on the side of the first direction, the part of the wall surface being a part on an opposite side from the combustion chamber in the center axis direction of the cylinder, and wherein when seen in the second direction, another part of the wall surface of the throat portion of the one of the intake ports is formed with an edge for orienting the intake air flowing near the other part of the wall surface, toward a center axis of an intake valve for opening and closing the one of the intake ports, the other part of the wall surface being a part on the combustion chamber side in the center axis direction of the cylinder.

4 . The intake device of claim 2 , wherein when seen in a center axis direction of each cylinder, the two intake ports of the cylinder extend to the combustion chamber in a first direction intersecting the center axis direction, and when seen in a second direction perpendicular to the center axis direction and the first direction, the two intake ports extend on an upper side of the combustion chamber while inclining to a combustion chamber side in the center axis direction, and open to the combustion chamber at opening portions of the intake ports, respectively, the opening portions located in a part of a surface of the cylinder head facing the combustion chamber, on an opposite side from the first direction,
wherein in the cylinder head, an intake valve seat having a substantially ring shape and having a sealing surface on an inward side in a radial direction of the intake valve seat, is attached to the opening portion of the one of the intake ports, and when seen in the second direction, a part of a wall surface of the throat portion of the one of the intake ports has a shape for guiding intake air flowing near the part of the wall surface, to flow substantially straight toward an area that is on the radially inward side of the sealing surface and near a part of the sealing surface located on the side of the first direction, the part of the wall surface being a part on an opposite side from the combustion chamber in the center axis direction of the cylinder, and wherein when seen in the second direction, another part of the wall surface of the throat portion of the one of the intake ports is formed with an edge for orienting the intake air flowing near the other part of the wall surface, toward a center axis of an intake valve for opening and closing the one of the intake ports, the other part of the wall surface being a part on the combustion chamber side in the center axis direction of the cylinder.

5 . The intake device of claim 1 , wherein the one of the two intake ports of each cylinder is located on one side of the cylinder with respect to a predetermined plane including the center axis of the cylinder, and the other intake port is located on the other side of the cylinder,
the engine includes, for each cylinder:
an ignition plug disposed in the cylinder head, in an extended line of the center axis of the cylinder;
a piston fitted into the cylinder and formed with a combustion cavity in a top face of the piston, on the center axis of the cylinder; and
a fuel injector for directly injecting fuel into the combustion chamber.

6 . The intake device of claim 2 , wherein one of the two intake ports of each cylinder is located on one side of the cylinder with respect to a predetermined plane including the center axis of the cylinder, and the other intake port is located on the other side of the cylinder,
the engine includes, for each cylinder:
an ignition plug disposed in the cylinder head, in an extended line of the center axis of the cylinder;
a piston fitted into the cylinder and formed with a combustion cavity in a top face of the piston, on the center axis of the cylinder; and
a fuel injector for directly injecting fuel into the combustion chamber.

7 . The intake device of claim 3 , wherein one of the two intake ports of each cylinder is located on one side of the cylinder with respect to a predetermined plane including the center axis of the cylinder, and the other intake port is located on the other side of the cylinder,
the engine includes, for each cylinder:
an ignition plug disposed in the cylinder head, in an extended line of the center axis of the cylinder;
a piston fitted into the cylinder and formed with a combustion cavity in a top face of the piston, on the center axis of the cylinder; and
a fuel injector for directly injecting fuel into the combustion chamber.

8 . The intake device of claim 4 , wherein one of the two intake ports of each cylinder is located on one side of the cylinder with respect to a predetermined plane including the center axis of the cylinder, and the other intake port is located on the other side of the cylinder,
the engine includes, for each cylinder:
an ignition plug disposed in the cylinder head, in an extended line of the center axis of the cylinder;
a piston fitted into the cylinder and formed with a combustion cavity in a top face of the piston, on the center axis of the cylinder; and
a fuel

Assignees

• Mazda Motor

Inventors

• Nakahara Yasushi
• Wada Yoshitaka
• Suzuki Yohei
• Nabetani Yuki

Classifications

• F02F1/4235 Primary

  of intake channels · CPC title

• F02F1/242

  Arrangement of spark plugs or injectors · CPC title

• F02M35/10157

  Supercharged engines · CPC title

• F02B2075/125

  Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber · CPC title

• F02B31/085

  having two inlet valves · CPC title