A motor includes a motor body part and a cap member. The motor body part includes a stationary unit, a rotary unit arranged to rotate about a center axis, and a bearing fixed to the stationary unit and arranged to rotatably support the rotary unit. The cap member includes a top surface portion extending perpendicularly to the center axis, a bottom surface portion disposed below the top surface portion and having a larger outer diameter than the top surface portion, and a connecting portion which connects the top surface portion and the bottom surface portion. The connecting portion includes a first connecting portion which connects an outer edge of the top surface portion and an outer edge of the bottom surface portion, and a second connecting portion which connects the outer edge of the top surface portion and an inner edge of the bottom surface portion.

A motor includes a stationary unit and a rotary unit. The rotary unit includes a shaft, a magnet, and a rotor holder for holding the magnet on an inner circumferential surface thereof The rotor holder includes a top surface portion extending in a direction orthogonal to a center axis, a first surface portion extending radially outward from a radial outer end portion of the top surface portion, a second surface portion positioned axially below the top surface portion and having an outer diameter larger than an outer diameter of the first surface portion, a first connecting portion arranged to connect a radial outer end portion of the first surface portion and a radial outer end portion of the second surface portion, and a second connecting portion arranged to connect the radial outer end portion of the top surface portion and a radial inner end portion of the second surface portion.

A compressor includes a rotor configured to compress air and driven by a shaft. A motor is drives the shaft. The first and second journal bearings facilitate rotation of the shaft. The first journal bearing is upstream from the motor and the second journal bearing is downstream from the motor. The transfer tube is configured to provide cooling air from a bearing cooling air inlet to the first journal bearing. A method for cooling a compressor is also disclosed.

A fluid-dynamic bearing system comprising a stationary bearing component (12, 16, 18) and a bearing component (14, 14a) rotatable about a rotation axis, wherein, during operation of the bearing, the stationary and rotary components are separated from each other by a bearing gap (20) filled with a bearing fluid, wherein at least one fluid-dynamic radial bearing (22, 24) and at least one fluid-dynamic thrust bearing (28) or, alternatively, at least one conical fluid-dynamic bearing are arranged along the bearing gap (20), and wherein the bearing gap (20) comprises first and second open ends sealed by a first sealing gap (34) and a second sealing gap (36). The second sealing gap (36) exclusively extends normal to the rotation axis (40).

A drive assembly having a motor accommodating bore for an electric motor, the bore being directed perpendicularly into an end face of a block-like accommodating body, and having a motor housing for accommodating a bearing provided for a motor shaft of the electric motor the bearing being fixed in an end-side motor housing section which extends into the motor accommodating bore. The invention provides for the electric motor to be frictionally fixed and centered in the motor accommodating bore by a motor holder that is fastened to the end-side motor housing section and projects into the motor accommodating bore.

The purpose of this invention is to achieve an electric air flow control device comprising a motor rotor bearing structure having excellent wear resistance even with loads from striking caused by a high vibrational environment specific to an internal combustion engine. A cylindrical sintered metal slide bearing is used in at least one of a front bearing (16) and a rear bearing (17) that support a rotor shaft (14) of a motor (3) that is the rotary control drive source of a throttle valve (7) that controls the intake air flow to an internal combustion engine, and the bearing design is such that the relationship of the radial crushing strength and the compressive deformation rate of the cylindrical sintered metal bearing has the mechanical properties of a maximum radial crushing strength of 230 N/mm2 or greater and a maximum compressive deformation rate of 3.5% or greater at the maximum radial crushing strength.

A bearing mechanism includes a stationary portion and a rotating portion. The stationary portion includes a shaft portion and a plate portion. The rotating portion includes a sleeve including an annular portion, a cylindrical portion, an annular bottom surface, and a first communication hole. The rotating portion includes a ring member arranged to cover at least a portion of an opening of the first communication hole, and faces the plate portion via a first gap. A pumping groove array is disposed in the plate portion or the ring member. A second communication hole is disposed between the ring member and the annular bottom surface, and connected to the first communication hole. At least a portion of the opening of the second communication hole is positioned on a farther radial direction inner side than the pumping groove array.

To provide an actuator in which an unstable movement of a rotor is controlled. An actuator includes a coil, a bobbin around which the coil is wound, a rotor positioned inside the bobbin, a shaft to which the rotor is fixed and which is rotatably supported, a stator including a base portion positioned on one end side of the shaft, outer magnetic pole portions extending from the base portion along the shaft and positioned outside the bobbin and inner magnetic pole portions extending from the base portion along the shaft and positioned between the rotor and the inside of the bobbin, a stator including a base portion positioned on the other end side of the shaft, outer magnetic pole portions extending from the base portion along the shaft and positioned outside the bobbin and inner magnetic pole portions extending from the base portion along the shaft and positioned between the rotor and the inside of the bobbin and a cover positioned between the rotor and the stator and contacting tip portions of the inner magnetic pole portions to regulate the approach of the inner magnetic pole portions to the rotor.

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.

Provided is a slide bearing (bearing sleeve (8)), comprising an oxidized green compact in which particles (11) of metal powder are bonded to each other by an oxide film (12) formed on surfaces of the particles (11). The oxidized green compact has a bearing surface (A, B) configured to slide, through intermediation of a lubricating film, relative to a mating member (shaft member (2)) to be supported. The bearing surface (A, B) has a large number of opening portions (13a), and the large number of opening portions (13a) and inner pores (13b) are interrupted in communication therebetween by the oxide film (12).