Valve arrangement

1. A valve arrangement included in an engine peripheral structure provided with an intake system in an engine room, the intake system comprising:

a low-pressure intake passage, arranged around an engine main body mounted in the engine room and connected to a passage upstream of a supercharger of the intake system in an intake direction;

a high-pressure intake passage, connected to a passage downstream of the supercharger in the intake direction; and

an air bypass valve connected between the low-pressure intake passage and the high-pressure intake passage,

wherein the air bypass valve includes: an exit side opening connected to the low-pressure intake passage; an air introducing hole formed around the exit side opening as an opening and communicating with the high-pressure intake passage; and an open-close valve to open or close the exit side opening and the air introducing hole,

wherein the air introducing hole is an elongate hole extending in a peripheral direction about the exit side opening, and

wherein a whole of the air bypass valve is provided, in a cross-sectional view in a direction orthogonal to the intake direction of the low-pressure intake passage, in a region of the low-pressure intake passage closer to the engine main body with respect to an imaginary line which passes through the center of the low-pressure intake passage and is parallel to a cylinder axial direction of the engine main body.

2. The valve arrangement according to claim 1 further comprising:

a bypass piping extending from the high-pressure intake passage connected to the air bypass valve; and

a chamber connected between the bypass piping and the air bypass valve and disposed on an upper side surface of the low-pressure intake passage,

wherein the chamber is provided, at a position facing opposite to the engine main body, with a connection joint which delivers a high-pressure intake air from the high-pressure intake passage.

3. The valve arrangement according to claim 2 ,

wherein the air introducing hole is in communication with the high-pressure intake passage through the chamber,

wherein the air introducing hole has, with respect to an imaginary line of a boundary which is orthogonal to an axis of the bypass piping in a connector between the chamber and the bypass piping and passes through the center of the exit side opening, one region on a side closer to the connector and the other region on the opposite side from the connector, and

wherein said the other region is larger in area than the said one region.

4. The valve arrangement according to claim 1 ,

wherein the low-pressure intake passage is formed with a seat portion on which a jet purge device is fixed.

5. The valve arrangement according to claim 2 ,

wherein the low-pressure intake passage is formed with a seat portion on which a jet purge device is fixed.

6. The valve arrangement according to claim 3 ,

wherein the low-pressure intake passage is formed with a seat portion on which a jet purge device is fixed.

7. The valve arrangement according to claim 2 ,

wherein a solenoid to control the air bypass valve is disposed closer to the engine main body than the low-pressure intake passage,

wherein the solenoid is connected to a joint and the connection joint using respective piping, and

wherein the joint is provided on a side surface of the low-pressure intake passage opposite to the engine main body and near the air bypass valve.

8. The valve arrangement according to claim 3 ,

wherein a solenoid to control the air bypass valve is disposed closer to the engine main body than the low-pressure intake passage,

wherein the solenoid is connected to a joint and the connection joint using respective piping, and

wherein the joint is provided on a side surface of the low-pressure intake passage opposite to the engine main body and near the air bypass valve.