Abstract: A multiblade centrifugal blower includes a centrifugal fan including a hub rotated by a motor, and plural curved rectangular blades arranged at predetermined intervals in a circumferential direction of the hub forming a cylindrical basket with an opening on a front side of the hub, and a scroll casing including an air inlet and an air outlet, and houses the centrifugal fan inside to face the air inlet. A length from a rear end to an front end of an outer edge of the blade is shorter than a length from a rear end to an front end of an inner edge of the blade, and a bell mouth is configured such that distance between a tip part of the inner edge of the blade and an inner wall of the scroll casing is the minimum at an inner tip part P of the bell mouth of the air inlet.

Abstract: A plurality of curved rectangular blades are arranged in a circumferential direction on a periphery of a disc, forming a pipe-like basket shape with an opening on a front side of the disc. Rotation of the disc draws in air from the opening and draws out the air in a centrifugal direction through a space between the blades. The blades are formed of a thick plate part close to the disc and a thin plate part that is thinner than the thick plate part and farther than the thick plate part from the disc. A bulge serving as a boundary between the thick plate part and the thin plate part is formed on a negative pressure surface of the blades, which is of curved convex shape.

Abstract: A multiblade centrifugal blower in which a length from a rear end to a front end of an outer edge of a blade is shorter than a length from a rear end to a front end of an inner edge of the blade. Moreover, a bell mouth is located at an air inlet such that a distance from a tip part of an inner edge of the blade to an inner wall of a scroll casing is minimum at an inner tip part of the bell mouth.

Abstract: A plurality of curved rectangular blades are arranged in a circumferential direction on a periphery of a disc, forming a pipe-like basket shape with an opening on a front side of the disc. Rotation of the disc draws in air from the opening and draws out the air in a centrifugal direction through a space between the blades. The blades are formed of a thick plate part close to the disc and a thin plate part that is thinner than the thick plate part and farther than the thick plate part from the disc. A bulge serving as a boundary between the thick plate part and the thin plate part is formed on a negative pressure surface of the blades, which is of curved convex shape.

Abstract: A blower includes: an impeller on which there are arranged axial flow blades 40 mounted at circumferential intervals to an outer peripheral surface of a boss; a case surrounding the impeller; and a bell mouth cylindrically constricted to guide gas into the case, wherein an inner diameter of the bell mouth is smaller than an outer diameter of the impeller. Further, each blade has, in the radial direction, a sweepforward wing portion situated on the boss side and exhibiting a positive advance ratio value, and a sweepback wing portion situated on the outer peripheral side of the blade and exhibiting a negative advance ratio value, with the arc length of each blade increasing from the boss side toward the outer peripheral side. Therefore, it is possible to achieve an improvement in ventilation efficiently, through an increase in static pressure and to achieve a reduction in noise.

Abstract: A blower includes: an impeller on which there are arranged axial flow blades 40 mounted at circumferential intervals to an outer peripheral surface of a boss; a case surrounding the impeller; and a bell mouth cylindrically constricted to guide gas into the case, wherein an inner diameter of the bell mouth is smaller than an outer diameter of the impeller. Further, each blade has, in the radial direction, a sweepforward wing portion situated on the boss side and exhibiting a positive advance ratio value, and a sweepback wing potion situated on the outer peripheral side of the blade and exhibiting a negative advance ratio value, with the arc length of each blade increasing from the boss side toward the outer peripheral side. Therefore, it is possible to achieve an improvement in ventilation efficiently, through an increase in static pressure and to achieve a reduction in noise.

Abstract: A fan according to the present invention can be monolithically molded out of a metal with a low energy in combination with a structure of a metal mold, in which gate arrangement and/or distribution of dimensions of vanes is devised in injecting a low melting-point metal such as magnesium, wherein not only production but also reproducing such as recycling are facilitated, and also a metalwave of the fan can be produced in consideration of the global atmosphere preservation.

Abstract: A fan according to the present invention can be monolithically molded out of a metal with a low energy in combination with a structure of a metal mold, in which gate arrangement and/or distribution of dimensions of vanes is devised in injecting a low melting-point metal such as magnesium, wherein not only production but also reproducing such as recycling are facilitated, and also a metalwave of the fan can be produced in consideration of the global atmosphere preservation.

Abstract: A fan according to the present invention can be monolithically molded out of a metal with a low energy in combination with a structure of a metal mold, in which gate arrangement and/or distribution of dimensions of vanes is devised in injecting a low melting-point metal such as magnesium, wherein not only production but also reproducing such as recycling are facilitated, and also a metalwave of the fan can be produced in consideration of the global atmosphere preservation.