Abstract: In a fan, a housing includes decreased thickness portions and increased thickness portions arranged alternately in a circumferential direction. A distance between a central axis and an edge increases from an air inlet toward an air outlet. An inner circumferential surface has a minimum radius smaller than a distance between the central axis and an outermost portion of the edge. At a boundary between upper and lower housing portions of the housing, the inner circumferential surface has a radius greater than the distance between the central axis and the outermost portion of the edge. The increased thickness portions include component fastening structures defining a fastening structure arranged to fit the upper and lower housing portions to each other.

Abstract: A fan motor includes a base member including a bottom plate portion, a bearing support portion, and a screw receiving portion. The bottom plate portion extends in directions perpendicular or substantially perpendicular to a central axis below a circuit board. The bearing support portion extends upward from the bottom plate portion and has a cylindrical or substantially cylindrical shape. The screw receiving portion is arranged to project upward from the bottom plate portion on a radially outer side of the bearing support portion. At least a portion of the screw receiving portion is arranged in a hole portion defined in the circuit board.

Abstract: A fan motor includes a motor; an impeller; a motor control board; an AC/DC converter board; electronic components mounted on the AC/DC converter board; and a housing arranged to contain the motor, the impeller, the motor control board, and the AC/DC converter board. The housing includes a base portion arranged to hold a stationary portion of the motor on an axially upper side thereof; and a case portion arranged to extend to assume a tubular shape on an axially lower side of the base portion. The AC/DC converter board is arranged in an interior space of the case portion. At least a portion of the interior space is filled with a resin material. Surfaces of the AC/DC converter board and the electronic components are covered with the resin material. The fan motor further includes a projecting portion arranged to project into the interior space.

Abstract: An insulator of a motor includes a body portion and a wire guide portion. The body portion is arranged to cover an upper surface, a lower surface, and circumferential side surfaces of each of a plurality of teeth. The wire guide portion is arranged to project downward from the body portion. A drawn-out portion of an electric wire which extends from a coil is arranged to reach a land portion arranged on a lower surface of a circuit board after passing through the wire guide portion. In addition, an area of contact between the drawn-out portion and the wire guide portion is arranged at an axial height lower than that of the lower surface of the circuit board.

Abstract: In an axial fan, a housing includes a side wall arranged to surround an outer circumference of an impeller, and a substantially square or substantially rectangular flange arranged to project radially outward from an outer circumferential surface of the side wall. The side wall preferably includes three slit groups each including a plurality of slits arranged in a circumferential direction and arranged to extend through the side wall from an inner circumferential surface to the outer circumferential surface thereof. Two of the slit groups are defined in portions of the side wall which correspond to two adjacent corner portions in an upper half portion of the flange, while the remaining slit group is defined in a portion of the side wall which corresponds to a lower half portion of the flange. The upper and lower half portions are divided at a line parallel or substantially parallel to two opposing sides of the flange and passing through a central axis.

Abstract: A motor includes a cover made of a resin material. The cover includes a first annular portion arranged to extend in an annular shape above coils, a side wall portion arranged to extend downward from an outer circumferential portion of the first annular portion, and a second annular portion arranged to extend radially outward or radially inward from a lower end portion of the side wall portion along an upper surface of a circuit board. The side wall portion is arranged to extend in an axial direction while filling in gaps between teeth on a radially inner side of radially outer end surfaces of the teeth. The coils are covered by the cover to be protected from dust, water droplets, etc. The radially outer end surfaces of the teeth are exposed from the cover, and are thus arranged to be in radial proximity to a rotor magnet.

Abstract: An insulator of a motor includes a body portion and a wire guide portion. The body portion is arranged to cover an upper surface, a lower surface, and circumferential side surfaces of each of a plurality of teeth. The wire guide portion is arranged to project downward from the body portion. A drawn-out portion of an electric wire which extends from a coil is arranged to reach a land portion arranged on a lower surface of a circuit board after passing through the wire guide portion. In addition, an area of contact between the drawn-out portion and the wire guide portion is arranged at an axial height lower than that of the lower surface of the circuit board.

Abstract: A fan motor includes a base member including a bottom plate portion, a bearing support portion, and a screw receiving portion. The bottom plate portion extends in directions perpendicular or substantially perpendicular to a central axis below a circuit board. The bearing support portion extends upward from the bottom plate portion and has a cylindrical or substantially cylindrical shape. The screw receiving portion is arranged to project upward from the bottom plate portion on a radially outer side of the bearing support portion. At least a portion of the screw receiving portion is arranged in a hole portion defined in the circuit board.

Abstract: An axial flow fan includes an impeller rotatable about a central axis with a plurality of rotor vanes, a motor that drives the impeller, a base portion that supports the motor, a housing that includes an intake vent, an exhaust vent, and an inner peripheral surface surrounding the impeller and the motor, and a plurality of stator vanes that respectively connects the base portion and the housing, wherein the inner peripheral surface includes a first inner peripheral surface arranged to increase a distance from the central axis toward the intake vent or the exhaust vent in an axial direction, and a recess provided between the first inner peripheral surface and a stator vane included in the plurality of stator vanes and facing the first inner peripheral surface. Thus, airflow is allowed to smoothly pass through the housing, resulting in a decrease in noise generated in the fan.

Abstract: A rotating portion of a motor includes a rotor holder including a cylindrical portion arranged to be coaxial or substantially coaxial with a central axis, a plurality of magnets arranged in a circumferential direction on an inner circumferential surface of the cylindrical portion, and a resin portion arranged on a surface of the rotor holder. The resin portion includes a plurality of ribs arranged at regular or substantially regular intervals in the circumferential direction along the inner circumferential surface of the cylindrical portion, and an outer tubular portion arranged to cover an outer circumferential surface of the cylindrical portion. Each rib and the outer tubular portion are arranged to be defined by a single monolithic member such that each rib and the outer tubular portion are continuous with each other. Each magnet is preferably arranged between a separate pair of adjacent ones of the ribs.

Abstract: A motor includes a cover made of a resin material. The cover includes a first annular portion arranged to extend in an annular shape above coils, a side wall portion arranged to extend downward from an outer circumferential portion of the first annular portion, and a second annular portion arranged to extend radially outward or radially inward from a lower end portion of the side wall portion along an upper surface of a circuit board. The side wall portion is arranged to extend in an axial direction while filling in gaps between teeth on a radially inner side of radially outer end surfaces of the teeth. The coils are covered by the cover to be protected from dust, water droplets, etc. The radially outer end surfaces of the teeth are exposed from the cover, and are thus arranged to be in radial proximity to a rotor magnet.

Abstract: An axial flow fan includes an impeller rotatable about a central axis with a plurality of rotor vanes, a motor that drives the impeller, a base portion that supports the motor, a housing that includes an intake vent, an exhaust vent, and an inner peripheral surface surrounding the impeller and the motor, and a plurality of stator vanes that respectively connects the base portion and the housing, wherein the inner peripheral surface includes a first inner peripheral surface arranged to increase a distance from the central axis toward the intake vent or the exhaust vent in an axial direction, and a recess provided between the first inner peripheral surface and a stator vane included in the plurality of stator vanes and facing the first inner peripheral surface. Thus, airflow is allowed to smoothly pass through the housing, resulting in a decrease in noise generated in the fan.

Abstract: In an axial fan, a housing includes a side wall arranged to surround an outer circumference of an impeller, and a substantially square or substantially rectangular flange arranged to project radially outward from an outer circumferential surface of the side wall. The side wall preferably includes three slit groups each including a plurality of slits arranged in a circumferential direction and arranged to extend through the side wall from an inner circumferential surface to the outer circumferential surface thereof. Two of the slit groups are defined in portions of the side wall which correspond to two adjacent corner portions in an upper half portion of the flange, while the remaining slit group is defined in a portion of the side wall which corresponds to a lower half portion of the flange. The upper and lower half portions are divided at a line parallel or substantially parallel to two opposing sides of the flange and passing through a central axis.

Abstract: A fan for generating an air flow by rotating an impeller with a motor is provided. A cylindrical outer side surface of a rotor of the motor is press-fitted to an inner side surface of the impeller cup which is substantially cylindrical. An outer side surface of the impeller cup is a portion of a circular conical surface, thereby increasing the amount of air generated and transmitted by the fan. A gap is formed between the outer side surface and the inner cylindrical surface of the impeller cup. The cylindrical outer side surface of the rotor is connected to the inside of the inner cylindrical surface of the impeller cup coaxially with each other. Thus, the impeller and the rotor can be reliably fixed to each other with improved performance of transmitting air.

Abstract: A centrifugal fan preferably includes a stator portion; a substantially cylindrical rotor holder; an annular support plate secured to an outer circumferential surface and/or a lower end portion of the rotor holder; and a plurality of blades secured to the support plate. The support plate is integrally defined by a substantially annular blade support portion arranged radially farthest from the rotor holder to support the plurality of blades; a cylindrical portion arranged radially closest to the rotor holder to encircle the outer circumferential surface of the rotor holder; and a sloping portion arranged between the blade support portion and the cylindrical portion to slope from an upper end portion of the cylindrical portion to the blade support portion.

Abstract: A fan for generating an air flow by rotating an impeller with a motor is provided. A cylindrical outer side surface of a rotor of the motor is press-fitted to an inner side surface of the impeller cup which is substantially cylindrical. An outer side surface of the impeller cup is a portion of a circular conical surface, thereby increasing the amount of air generated and transmitted by the fan. A gap is formed between the outer side surface and the inner cylindrical surface of the impeller cup. The cylindrical outer side surface of the rotor is connected to the inside of the inner cylindrical surface of the impeller cup coaxially with each other. Thus, the impeller and the rotor can be reliably fixed to each other with improved performance of transmitting air.

Abstract: An axial flow fan includes a housing that is formed by a process including injection molding includes a tapered surface at a frame portion thereof. One end of at least one rib is connected to an attachment portion which is a part of a stator portion of a motor portion, and the other end the rib is connected to a base portion protruding from the tapered surface. Two inclined surfaces connected to the tapered surface at the base portion and arranged in a circumferential direction with respect to a central axis are inclined such that the further a portion of the inclined surface from the central axis is, the further the portion is from a center of the rib. As a result, an air flow disturbance generated by the base portion between the rib and the frame portion is minimized, thereby reducing a noise generated due to the air flow disturbance.

Abstract: A centrifugal fan includes an impeller that rotates inside the elongated cylindrical housing and a motor for driving the impeller. The impeller and the motor are arranged tandem in the axial direction. The impeller includes a blade portion having plural blades elongated in the axial direction, and the blades are arranged at a predetermined pitch in the circumferential direction. When the impeller rotates, air is taken in through a suction opening provided to the tip portion in the axial direction of the housing and is blown out through an outlet opening that is provided to a part in the circumferential direction of the housing. A bearing portion that constitutes the motor is a sleeve bearing including a shaft member and a sleeve having a cylindrical shape that engages the shaft member with a clearance. One of the shaft member and the sleeve is fixed to a rotational member, while the other is fixed to a base member.

Abstract: A centrifugal fan includes an impeller including a blade portion having plural elongated blades arranged at a predetermined pitch in the circumferential direction and a motor for rotating the impeller. The impeller and the motor are arranged side by side in the axial direction. A diameter of the impeller is less than or equal to 25 millimeters. A radius r of the impeller and a length h in the axial direction of the impeller satisfies the relationship of 2r<=h<=20r. Among elements that constitute the motor, a torque generating portion including an armature and a field magnet, and a bearing portion that retains a rotational member in a rotatable manner to a fixed member are arranged side by side in the axial direction.