A vacuum pump for rotary driving a rotor by a motor to perform vacuum pumping, wherein a motor rotor of the motor includes a yoke fixed to a shaft of the rotor, and a permanent magnet held at the yoke, and the yoke includes a holding portion provided apart from the shaft and configured to hold the permanent magnet, and a pair of fitting portions provided respectively at both ends of the holding portion in an axial direction and bonded to the shaft by fitting, and a radial thickness dimension of each fitting portion is set less than that of the holding portion.

The present invention relates to a vacuum pump comprising a vacuum pumping mechanism comprising a rotor supported for rotation by a drive shaft, a first bearing assembly for controlling movement of the rotor during rotation of the drive shaft, a back-up bearing assembly for limiting said movement and a sensor for sensing when said movement is limited by the back-up bearing assembly.

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 vacuum pump in which a spark is not generated even when a rotor component and a stator component are brought into contact, and an explosive reaction in a vacuum container can be prevented, and a protection portion provided in the vacuum pump are provided. On head part sides of a thread ridge to a thread ridge of a threaded spacer with a narrow clearance of a gas channel therebetween, a protection portion 1a to a protection portion made of non-metal are formed in a peripheral state. A protection portion is similarly formed in the peripheral state also on an inner peripheral surface side of a stator blade spacer opposed to a distal end of a rotor blade with a narrow clearance of the gas channel. The protection portion is formed of non-metal with a sufficient thickness so that metal materials of base materials are not brought into contact with each other even when a rotor blade and a stationary portion are brought into contact with each other.

A vacuum pump which can prevent lowering of an exhaust performance of the vacuum pump, even if a linked-type thread groove spacer is fastened by a fixing bolt, is provided.

The linked-type thread groove spacer according to an embodiment of the present invention includes a structure for linking a Siegbahn pump portion and a thread-groove pump portion. When this linked-type thread groove spacer is to be fastened, a countersunk hole is provided in advance in an exhaust channel portion, and the linked-type thread groove spacer is fastened to a base by a fixing bolt. As a result, a head part of the fixing bolt does not protrude to the exhaust channel, and the head part of the fixing bolt does not make resistance against an exhaust gas. Thus, lowering of the exhaust performance of the vacuum pump can be suppressed.

Bobbins of an annular electromagnet each have a bobbin body that has a coil wire wound around an outer periphery thereof and is attached to a respective tooth of an annular stator core by having the corresponding tooth inserted therethrough. A first flange portion in a rectangular hallow shape is provided on an end surface of the bobbin body near the center of the annular stator core and a second flange portion in a rectangular hallow shape is provided on the other end surface of the bobbin body. A coil winding amount increasing means is formed at least on the first flange portion or the second flange portion and increases the amount of winding of the coil wire wound around the bobbin body.

An electric submersible pump (ESP) assembly. The ESP assembly comprises an electric motor, a centrifugal pump, and a hybrid magnetic radial bearing, wherein the hybrid magnetic radial bearing is disposed inside the electric motor or disposed inside the centrifugal pump.

A rotation mechanism (20) of a vacuum pump (100) includes a magnetic bearing unit (21) having a first outer diameter (91), the magnetic bearing unit (21) being operable as a first radial magnetic bearing (40), and a motor unit (22) provided on a side of a second end (11b) of a rotary shaft (11) relative to the magnetic bearing unit, the motor unit (22) having a second outer diameter (92) larger than the first outer diameter, the motor unit (22) being operable as both a motor (30) and a second radial magnetic bearing (50).

A vacuum pump and a vacuum pump rotor blade that can effectively limit deposition of reaction products are provided. The vacuum pump includes a rotating shaft held rotationally, a drive mechanism for the rotating shaft, a first rotor blade made of a first material, a second rotor blade made of a second material having higher heat resistance than the first material, and disposed further toward a downstream side than the first rotor blade, and a casing enclosing the rotating shaft, the first rotor blade, and the second rotor blade. The second rotor blade is disposed, via a heat insulating portion, on the first rotor blade.

An object is to prevent backflow of particles during discharging. The vacuum pump includes: a casing having an inlet port and an outlet port; a stator column provided upright inside the casing; a rotating body having a shape surrounding an outer circumference of the stator column; and a magnetic bearing configured to magnetically levitate and support a rotating shaft of the rotating body, with the vacuum pump being configured to suck gas from the inlet port and exhaust the gas from the outlet port by rotation of the rotating body, wherein a projection portion for discharging an electric charge carried on the rotating body is provided at at least one of a first position formed on a back surface side of the rotating body, a second position formed on a bottom surface side of the rotating body, and a third position formed in an intermediate point of a flow passage of the gas of the rotating body.