Supercharger for saddle-riding vehicle

1. A supercharger which pressurizes intake air for a combustion engine of a saddle-riding vehicle, the supercharger comprising:

a supercharger casing;

a centrifugal impeller;

an impeller casing including:

an outer peripheral wall located radially outward from the centrifugal impeller and a side wall located axially outward of the centrifugal impeller, the impeller casing covering the centrifugal impeller;

a first side wall rib provided at an outbound surface of the side wall and the side wall further provided with a suction port of the supercharger; and

an outer peripheral wall rib formed at an outbound surface of the outer peripheral wall, wherein

the first side wall rib extends radially along the outer surface of the side wall so as to transitionally connect to the outer peripheral wall rib extending axially along the outer surface of the outer peripheral wall, and

the outer peripheral wall rib has an outer mounting portion into which a fastener is received in a manner that connects the impeller casing to the supercharger casing, and

the outer mounting portion extends from one axial end to the other axial end of the outer peripheral wall.

2. The supercharger as claimed in claim 1 , wherein the first side wall rib extends from a radially inner portion of the side wall to a radially outer portion of the side wall, and is formed in a V-shape with the outer mounting portion as a base.

3. The supercharger as claimed in claim 1 , further comprising an inner mounting portion provided at the radially inner portion of the side wall of the impeller casing and configured to connect the impeller casing and an air cleaner member, wherein

the first side wall rib extends so as to be connected to the inner mounting portion.

4. The supercharger as claimed in claim 1 , wherein a plurality of the first side wall ribs are formed so as to be spaced apart from each other in a circumferential direction and are formed in a V-shape as viewed in an axial direction.

5. The supercharger as claimed in claim 1 , wherein the outer mounting portion includes a boss which extends in the axial direction on the outer peripheral wall, and the boss has a bolt insertion hole therein, into which a bolt is inserted.

6. The supercharger as claimed in claim 1 , further comprising:

a transmission mechanism being disposed in the supercharger casing, the transmission mechanism transmitting power supplied from the combustion engine to the centrifugal impeller; and

a supercharger rotation shaft is disposed along a longitudinal axis and which connects the transmission mechanism to the centrifugal impeller; wherein

at least two first side wall ribs are provided, and

the at least two first side wall ribs are connected together to form a V-shape on an outer peripheral wall of the impeller casing as viewed in an axial direction toward the impeller casing from a position along the longitudinal axis external to the impeller casing.

7. The supercharger as claimed in claim 6 further comprising an air cleaner mounted on the impeller casing adjacent the supercharger casing, which air cleaner cleans outside air.

8. The supercharger as claimed in claim 6 , wherein the vehicle is a motorcycle.

9. A supercharger which pressurizes intake air for a combustion engine of a saddle-riding vehicle, the supercharger comprising:

a supercharger casing;

a centrifugal impeller;

an impeller casing including;

an outer peripheral wall located radially outward of the centrifugal impeller and a side wall located axially outward of the centrifugal impeller, the impeller casing covering the centrifugal impeller;

a first side wall rib is provided at an outbound surface of the side wall and the side wall is further provided with a suction port of the supercharger;

the outer peripheral wall rib is formed at an outbound surface of the outer peripheral wall;

an inner mounting portion is provided at the radially inner portion of the side wall of the casing and is configured to connect the casing and an air cleaner; and

a second side wall rib provided at the side wall of the impeller casing, which side wall is provided with the suction port of the supercharger, the second side wall rib extending radially, wherein

the first side wall rib extends radially along the outer surface of the side wall so as to be transitionally connected to the outer peripheral wall rib extending axially along the outer surface of the outer peripheral wall,

the outer peripheral wall rib has an outer mounting portion into which a fastener is received in a manner that connects the impeller casing to the supercharger casing,

the first side wall rib extends so as to be connected to the inner mounting portion, and

the second side wall rib extends so as to be connected to the inner mounting portion.

10. The supercharger as claimed in claim 9 , wherein

the inner mounting portion is disposed at a circumferential position different from that of the outer mounting portion.

11. The supercharger as claimed in claim 9 , wherein the first side wall rib extends from a radially inner portion of the side wall to a radially outer portion of the side wall, and is formed in a V-shape with the outer mounting portion as a base.

12. The supercharger as claimed in claim 9 , wherein a plurality of the first side wall ribs are formed so as to be spaced apart from each other in a circumferential direction and are formed in a V-shape as viewed in an axial direction.

13. The supercharger as claimed in claim 9 , further comprising:

a transmission mechanism being disposed in the supercharger casing, the transmission mechanism transmitting power supplied from the combustion engine to the centrifugal impeller; and

a supercharger rotation shaft disposed along a longitudinal axis and which connects the transmission mechanism to the centrifugal impeller, wherein

at least two first side wall ribs are provided, and

the at least two first side wall ribs are connected together to form a V-shape as viewed in an axial direction toward the impeller casing from a position along the longitudinal axis external to the impeller casing.

14. A supercharger which pressurizes intake air for a combustion engine of a saddle-riding vehicle, the supercharger comprising:

a supercharger casing;

a centrifugal impeller;

an impeller casing including:

an outer peripheral wall located radially outward of the centrifugal impeller and a side wall located axially outward of the centrifugal impeller, the impeller casing covering the centrifugal impeller;

a first side wall rib provided at an outbound surface of the side wall and the side wall is further provided with a suction port of the supercharger; and

an outer peripheral wall rib is formed at an outbound surface of the outer peripheral wall, wherein

the first side wall rib extends radially along the outer surface of the side wall so as to be transitionally connected to the outer peripheral wall rib extending axially along the outer surface of the outer peripheral wall,

the outer peripheral wall rib has an outer mounting portion into which a fastener is received in a manner that connects the impeller casing to the supercharger casing, and

a plurality of outer peripheral wall ribs extend on an outer peripheral wall of the impeller casing and a plurality of side wall ribs extend in an axial dimension further than the axial dimensions of the side wall of the impeller casing.

15. The supercharger as claimed in claim 14 , wherein the outer peripheral wall ribs are spaced around the impeller casing and the side wall ribs are spaced around the side wall.

16. The supercharger as claimed in claim 14 , wherein the first side wall rib extends from a radially inner portion of the side wall to a radially outer portion of the side wall, and is formed in a V-shape with the outer mounting portion as a base.

17. The supercharger as claimed in claim 14 , wherein a plurality of the first side wall ribs are formed so as to be spaced apart from each other in a circumferential direction and are formed in a V-shape as viewed in an axial direction.

18. The supercharger as claimed in claim 14 , further comprising:

a transmission mechanism being disposed in the supercharger casing, the transmission mechanism transmitting power supplied from the combustion engine to the centrifugal impeller; and

a supercharger rotation shaft disposed along a longitudinal axis and connects the transmission mechanism to the centrifugal impeller, wherein

at least two first side wall ribs are provided, and

the at least two first side wall ribs are connected together to form a V-shape as viewed in an axial direction toward the impeller casing from a position along the longitudinal axis external to the impeller casing.