To provide a vacuum pump that is capable of efficiently cooling gas and requires less maintenance. The vacuum pump includes: a main body casing having an inlet portion and an outlet portion for gas; a turbomolecular pump mechanism portion in which a stator blade and a rotor blade are formed; a thread groove pump mechanism portion provided at a downstream side of the turbomolecular pump mechanism portion; a cooling trap portion that cools the gas led out from the turbomolecular pump mechanism portion and causes the gas to flow out to a side of the thread groove pump mechanism portion; and a partition wall that guides the gas led out from the turbomolecular pump mechanism portion to the cooling trap portion.

A rotor of a vacuum pump has a circular member that is driven rotatably, a cylindrical member joined to an outer circumference of the circular member, and a thread groove pump flow path formed between the cylindrical member and a stator member surrounding an outer circumference of the cylindrical member. The cylindrical member is made of a material having at least a feature of lower thermal expansivity or lower creep rate than that of a material of the circular member. A gap of a second region provided between a non-joint portion of the cylindrical member and the stator member is set to be smaller than a gap of a first region provided between a joint portion of the cylindrical member and the stator member.

An electromagnet unit in which influence of a noise on a displacement sensor is suppressed and which can be installed in a space-saving manner and a vacuum pump including the electromagnet unit are provided. An electromagnet unit includes a radial electromagnet which controls a shaft to a predetermined position, a radial sensor which detects a position of the shaft, and a printed board interposed between the radial electromagnet and the radial sensor and on which a wiring pattern for sensor connecting coils of the corresponding two radial sensors to each other and a wiring pattern connecting coils of the corresponding two radial electromagnets to each other are provided. The wiring pattern for sensor and the wiring pattern for electromagnet are disposed so as not to overlap when seen from the axial direction.

A thread groove pump portion, which is an exhaust element, is structured such that a Siegbahn structure is attached onto a cylindrical thread, and such that respective parts are connected to each other at this attachment section. A flow channel of the Siegbahn portion and a flow channel of the cylindrical thread (the thread groove pump portion) are connected to each other so as to substantially form a right angle when viewed from an axis direction of the vacuum pump, thus, the flow channel of the Siegbahn portion and the flow channel of the thread groove pump portion are connected to each other. the length of a compression flow channel of the thread groove pump portion can be increased in a radial direction due to the connected Siegbahn portion.

Provided is a vacuum pump that prevents the solidification of gas while being operated properly. The vacuum pump includes a rotor that is supported rotatably on a base, a stator that has a thread groove portion, and a heating structure that heats the stator. The heating structure has a spacer that insulates the stator from stator components other than the stator, and a cartridge heater that heats the stator. The distance between a rotor cylindrical portion and the stator at the inlet port side is set to be equal to or greater than the distance between the rotor cylindrical portion and the stator at the outlet port side.

A vacuum pump comprises a vacuum exhaust section, the vacuum exhaust section including a stator, and a rotor having a rotor cylindrical section, the rotor cylindrical section discharging gas in cooperation with the stator, a suction port; a base; an exhaust port disposed on the base, wherein at least a part of the exhaust port faces an outer peripheral surface of the stator, and gas sucked through the suction port by the vacuum exhaust section is discharged through the exhaust port; and a conductance increasing function section formed on at least one of the outer peripheral surface of the stator and an inner peripheral surface of the base, the outer peripheral surface and the inner peripheral surface facing an exhaust path for gas discharged by the rotor cylindrical section and the stator leading to the exhaust port.

A vacuum pump comprises: a base; a rotor shaft rotatably provided at the base; a rotor including rotor blades arranged in multiple stages and a rotor cylindrical portion, and attached to the rotor shaft; stationary blades each arranged between adjacent ones of the rotor blades, the stationary blades and the rotor blades forming a turbo exhaust portion; a stator forming, together with the rotor cylindrical portion, a screw groove exhaust portion; and a hexagon socket head cap screw configured to fix the stator to an upper surface of the base in a guiding path of the screw groove exhaust portion to which gas is guided from the turbo exhaust portion. The hexagon socket head cap screw is a bolt having a smaller height of a head portion than that of a hexagon socket head cap screw according to a provision of a country of use or an international organization.

A vacuum pump comprises: a pump housing; a motor configured to rotate in the pump housing; a rotor configured to be rotatably driven by the motor; a stator provided between the rotor and the pump housing; and a heat insulating member provided between the stator and the pump housing. The heat insulating member has a cylindrical main body and a processing gripping target portion provided on at least one of inner and outer peripheral surfaces of the main body.

A vacuum pump and a heat insulating member for the vacuum pump are provided that improve the rigidity and heat insulating effect of a heat insulating portion and facilitate the control of intended temperatures of components within the pump. A turbomolecular pump having at least a cooling function includes a heat insulator that is disposed on a threaded spacer and has a hollow structure including cavities extending in the axial direction.

One or more through-holes communicating with one or more of the plurality of screw grooves are formed at the cylindrical stator, a total of circumferential dimensions of the one or more through-holes formed at the cylindrical stator is set at equal to or greater than a circumferential dimension of an outer peripheral surface region of the cylindrical stator facing the second suction port, and a gas path through which inflow gas through the second suction port is guided to a screw groove is provided, the one or more through-holes penetrating through the screw groove and the screw groove being apart from the region facing the second suction port.