The bearing unit comprises: a bearing housing being formed into a cylindrical shape; and a bearing section being attached in the bearing housing. The bearing housing is made of resin. Grooves and projecting stripes are formed in an inner circumferential face of a housing hole of the bearing housing and an outer circumferential face of the bearing section, and they are extended in an axial direction. The bearing section is fitted into the bearing housing from an opening part of the bearing housing, in a state where the grooves and the projecting stripes are corresponded to each other, until the bearing section contacts an inner end face of the housing hole. A retaining projection of the bearing housing, which is formed at one end of the housing hole located on the one end side of the bearing housing, is deformed to overlap an end face of the bearing section.

The present invention proposes an electric blower which can strongly hold and fix a sleeve onto a frame, and eventually provide high reliability. An electric blower 1 includes a centrifugal fan 2; a shaft 9 installed integrally rotatably with the centrifugal fan 2; a sleeve 16; a bearing 17 provided in the sleeve 16 and adapted to rotatably support the shaft 9; a diffuser 6 provided with a through hole 21 in which the sleeve 16 is fixed; a recess 41 provided in an outer circumferential surface of the sleeve 16; and a stopper 43 filling a gap between the diffuser 6 and the recess 41 and adapted to harden and thereby prevent the sleeve 16 from being detached from the through hole 21.

A radial ventilator (1) has a base part (2), a housing part (4), with a discharge 33, placed on the base part (2), a motor electronics unit (98), and an internal rotor electric motor. The motor drives a ventilator wheel (3) via a shaft (7). The motor electronics unit (98) and a stator (32) of the electric motor are encapsulated by an extrusion coating (17) in the base part (2) and together form an integral one-piece structural unit. The radial ventilator (1) has a pressure chamber (D) enlarging in a spiral shape around the ventilator wheel (3). The pressure chamber (D) is formed and defined by the housing part (4) and the extrusion coating (17).

A sintered metal bearing is formed through sintering of a compact obtained through compression molding of raw-material powder. The sintered metal bearing includes chamfered portions that are respectively formed at least along outer rims of both end surfaces of the sintered metal bearing, and a dynamic pressure generating portion formed on an inner peripheral surface of the sintered metal bearing by sizing. An axial dimension of each of the chamfered portions is set larger than a radial dimension of the each of the chamfered portions, and a difference in axial dimension between the chamfered portions on one end side and another end side in an axial direction of the sintered metal bearing is set larger than a difference in radial dimension between the chamfered portions on the one end side and the another end side in the axial direction.

Fan modules and motors are disclosed. The fan motor includes a bearing holder having a first bearing holder end and a second bearing holder end. The bearing holder has a first section with a first diameter that is smaller than diameters of the first bearing holder end and the second bearing holder end. The motor further includes a first bearing retained by the bearing holder at the first bearing holder end, and a second bearing retained by the bearing holder at the second bearing holder end. The motor further includes a shaft retained by the first bearing and the second bearing, and a stator surrounding the first section of the bearing holder.

A magnetic bearing vacuum pump comprises: a first displacement signal generation section configured to amplify, by a resolution multiplying factor K of K>1, a displacement modulated wave signal modulated according to a displacement of the rotor from a predetermined position to generate a high-resolution displacement signal in a first displacement region including the predetermined position; a second displacement signal generation section configured to generate a low-resolution displacement signal in a larger second displacement region including the first displacement region; a selection section configured to select either one of the high-resolution displacement signal or the low-resolution displacement signal based on an unsteady-state response signal obtained by excluding a steady-state whirling displacement component from the high-resolution displacement signal or the low-resolution displacement signal; and a bearing control section configured to control the magnetic bearing based on the displacement signal selected by the selection section.

A rolling bearing that can prevent peeling on a surface of an iron-based metal member by hydrogen brittleness even under a severe environment is provided. The rolling bearing 1 has plural bearing elements formed of an iron-based metal, and a lubricant composition 7 that lubricates metal contact surfaces of the respective bearing elements, the lubricant composition 7 is a grease containing a base oil and alkanolamine and being free of alkali metal salts and alkaline earth metal salts of inorganic acids, the base oil is at least one oil selected from alkyl diphenyl ether oils, poly-α-olefin oils and ester oils, and the alkanolamine is contained by 0.1 to 10 parts by weight with respect to 100 parts by weight of the total amount of the base oil and a thickener.

A ratio W1/W2 of a circumferential width W1 of each of inclined hill portions G2 of a radial dynamic pressure generating portion G and a circumferential width W2 of each of inclined groove portions G3 is 1.2 or larger. And when an inner diameter of a bearing member is D, the circumferential width W2 of each of the inclined groove portions satisfies 0.2D≦W2≦0.4D.

The present disclosure provides a bearing assembly, a rotor assembly and a draught fan. The bearing assembly has a shaft sleeve and a shaft extending through the shaft sleeve. An inner wall of the shaft sleeve is provided with two grooves in a circumferential direction. The shaft is provided with two channels corresponding to the two grooves respectively. The channels and the grooves form two raceways. Multiple rolling bodies are disposed between the shaft and the shaft sleeve and movable in the raceways. The shaft sleeve has an outer diameter of 13 mm, and a portion of the shaft extending within the shaft sleeve has a diameter of 5 mm.

A motor includes a rotor having a rotation shaft, a stator arranged oppositely in a circumferential direction of the rotor, and a pair of bearing portions rotatably supporting the rotation shaft, the pair of bearing portions each include a first bearing being rotatable together with the rotation shaft and a second bearing being rotatable together with the first bearing, the first bearing rotates together with the rotation shaft when the first bearing is normal, and the second bearing as well as the first bearing rotates together with the rotation shaft when the first bearing is abnormal.