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 turbo compressor is disclosed. The turbo compressor may have an assembly-type rotational shaft where a permanent magnet is inserted into a connecting sleeve, at least one first locking projection formed on either an inner periphery of the connecting sleeve or an outer periphery of the permanent magnet facing the inner periphery of the connecting sleeve, and at least one first locking groove formed on the other. Thus, the permanent magnet constituting a rotor may be easily coupled into the rotational shaft, and the permanent may be effectively prevented from slipping. Moreover, a magnet embedded in the rotational shaft may be securely fixed so that it is held in a position where it is assembled, thus providing an advantage in concentrically aligning the magnet.

A stator unit includes a base member including a bearing housing extending along a rotation axis, a stator fixed to an outer circumferential surface of the bearing housing, and a molding resin part covering the stator. The stator includes a stator core having teeth protruding radially outward, an insulator for partially covering a surface of the stator core, and coils. A non-sealed space connected to an external space of the stator unit and a sealed space connected to an internal space of the stator unit are opposed through a contact location where the bearing housing or the base member makes contact with the molding resin part or the insulator. An angle α of the non-sealed space and an angle β of the sealed space opposed to each other through the contact location in a cross section including the rotation axis are set to satisfy a relationship of α>β.

An electric centrifugal pump having a motor housing, a pump head, a containment shell, and a rotor assembly consisting of a pump impeller and a permanent magnet rotor, wherein the pump head with the containment shell defines a wet chamber, in which the rotor assembly is arranged rotationally around a longitudinal motor axis, the containment shell with the motor housing defines a dry chamber, in which a wound stator is arranged, and the permanent magnet rotor is arranged within the stator and a hollow-cylindrical region of the containment shell. Particle accumulations in the region between the containment shell and the permanent magnet rotor cannot occur or can only occur to a very minor extent and that the consequences of impurities in the wet chamber are reduced in order to prevent premature wear or a blockage of the centrifugal pump.

A high-speed permanent magnetic motor assembly generates a magnetic field to produce mechanical output power. The assembly comprises a motor, a motor housing, and a radial bearing block. A motor housing supports a rotor and the radial bearing block with a left radial aerostatic bearing, a right aerostatic bearing, and an axial thrust aerostatic bearing. The bearings are porous aerostatic bearings that use a low-viscous vapor-liquid two-phase fluid as a lubricant, which penetrates through a porous bushing. The liquid vaporizes from pressure reduction, and part of the liquid arrives at a clearance between each of the bearings and the rotor. The liquid of the two-phase fluid is vaporized during discharge along an axial direction from the bearing. This increases the vapor in the clearance, improve a bearing capacity, retain position accuracy of an aerostatic bearing, and cool the aerostatic bearings and the rotor.

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 motor assembly includes a motor in a housing. The motor includes a stator and a rotor mounted in the stator casing, and an output shaft engaged with the rotor passes through the stator casing. Two opposite ends of the stator casing and the stator abuts against an annular plate and a rear end cap, respectively. Each screw passes through the rear end cap and the stator to screw into the annular plate, so the stator is fixed and restricted from moving axially in the stator casing. A front end of the housing is engaged with a motor fixing frame. The output shaft passes through a bearing on the motor fixing frame. The motor fixing frame is spaced from the motor. With such design, a vibration of the output shaft during operation is transmitted to the housing, but not directly affect the screws in the motor, thereby increasing the durability of the motor assembly.

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.

An electric motor includes a rotor with a rotor shaft mounted in at least one bearing bush of a friction bearing, a stator which surrounds the rotor, and at least one circular bearing plate which, relative to the rotor shaft, is mounted on the rotor shaft for co-rotation. An inner contour of the bearing plate surrounds a circumference of the rotor shaft by press-fit. The inner contour of the bearing plate is defined by at least two internal dimensions, wherein at least one internal dimension is smaller than the diameter of the rotor shaft. The at least one bearing plate is deformed in an axial direction when the bearing plate is in the pressed-in state on the rotor shaft.

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.