Patent ID: 7866945
Filing Date: 2011-01-11
Classification: F04D

Abstract:
1. An axial flow fan comprising: a housing including an air channel portion having a suction opening on one side of an axial direction of a rotary shaft and a discharge opening on the other side of the axial direction; an impeller including a plurality of rotary blades that rotate within the air channel portion, the plurality of rotary blades being disposed at equidistant intervals in a circumferential direction of the rotary shaft; a motor that causes the impeller to rotate about the rotary shaft in one rotating direction; and a plurality of stationary blades disposed in the vicinity of the discharge opening of the air channel portion, the plurality of stationary blades being disposed at equidistant intervals in the circumferential direction of the rotary shaft; wherein the number of the rotary blades is seven and the number of the stationary blades is eight, wherein the impeller includes a rotary blade fixing member having a peripheral wall portion onto which the rotary blades are fixed, wherein the stationary blades respectively have an outside end portion fixed to the inner wall portion of the air channel portion, and an inside end portion located opposite to the outside end portion in a radial direction of the rotary shaft, wherein a stationary blade fixing member is disposed in a central portion of the air channel portion in the vicinity of the discharge opening, the stationary blade fixing member including a peripheral wall portion having an outer diameter which is equal to or smaller than an outer diameter of the peripheral wall portion of the rotary blade fixing member, wherein the inside end portion of each of the stationary blades is fixed onto the peripheral wall portion of the stationary blade fixing member, wherein the stationary blades are respectively shaped so that a side of the outside end portion that extends along the inner wall portion may be longer than a side of the inside end portion that extends along the peripheral wall portion of the stationary blade fixing member, wherein the stationary blades are respectively shaped so that, assuming that a first hypothetical plane extends in a radial direction of the rotary shaft, passing through an end, located closest to the discharge opening, of the side of the inside end portion of the stationary blade and containing a centerline passing through the center of the rotary shaft, a second hypothetical plane extends in the radial direction, passing through an end, located closest to the discharge opening, of the side of the outside end portion of the stationary blade and containing the centerline, and a third hypothetical plane extends in the radial direction, passing through an end, located closest to the suction opening, of the side of the outside end portion of the stationary blade and containing the centerline, a direction from the first hypothetical plane to the second hypothetical plane and a direction from the second hypothetical direction to the third hypothetical direction are respectively opposite to the one rotating direction of the impeller, and wherein an angle θ