Patent ID: 8794196

Claim:
A chain saw, comprising: an engine; a cooling fan which is disposed on a lateral side of a crankcase of the engine, and which is rotationally driven by the engine; and a case that accommodates the engine and the cooling fan, wherein the cooling fan includes: a hub fixed on a crankshaft of the engine; a plurality of cooling vanes provided along an outer circumference of the hub; and an annular connector that connects the cooling vanes, wherein the case includes: a first cover that covers an outer side of the cooling fan; and a second cover that covers an inner side of the cooling fan, wherein the first cover is provided with a first outer-air intake that feeds outer air to the outer side of the cooling fan, and the second cover is provided with a second outer-air intake that feeds outer air to the inner side of the cooling fan, wherein the hub is provided with a through hole that axially penetrates the hub and intercommunicates the outer side and the inner side of the cooling fan, wherein the hub comprises spoke portions which extend radially outward from a center of the hub, the spoke portions being provided as structures different from the annular connector and the cooling vanes, the through hole being provided between two adjacent spoke portions, wherein the connector includes: an annular first connector that connects substantially central portions of the cooling vanes; and an annular second connector which is located axially closer to the inner side of the cooling fan than the first connector, wherein the first connector and the second connector are both ring-shaped, wherein the first connector and the second connector are connected to radially distal ends of the spoke portions of the hub, and wherein the cooling vanes are connected to the second connector such that radially proximal ends of the cooling vanes closest to the center of the hub extend toward the center of the hub not farther than a radially proximal end of the second connector which is closest to the center of the hub.