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.

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 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 comprises: a pump rotor portion configured such that multiple rotor blade stages including stacking portions formed in a ring shape and turbine blades radially formed on an outer peripheral side of the stacking portions are stacked on each other; a rotor shaft to which inner peripheral surfaces of the stacking portions of the multiple rotor blade stages stacked on each other are fixed; and a communication path allowing communication between a clearance space between the rotor shaft and each stacking portion and a pump exhaust path in which the turbine blades are arranged and discharging gas in the clearance space through the pump exhaust path.

A vacuum pump includes a housing, a rotatable shaft extending in an axial direction within the housing, a first pumping arrangement including a first stator arrangement and a first rotor arrangement, and a second pumping arrangement including a second stator arrangement and a second rotor arrangement. The vacuum pump further includes a spacer arranged between the first pumping arrangement and the second pumping arrangement. The spacer is coupled between the first stator arrangement and the second stator arrangement and is configured to provide a defined elasticity in the axial direction allowing an elastic deformation of the spacer in the axial direction.

A deposited material sensor is arranged, in a flow path of a gas from an inlet port to an outlet port, on an upstream side or a downstream side of a predetermined flow path position where a cause of disruption to operation of the vacuum pump is to occur. In addition, the deposited material sensor detects a presence or absence of deposited material at the arrangement position of the deposited material sensor, and the arrangement position of the deposited material sensor is a position where a thickness of the deposited material at the predetermined flow path position assumes a predetermined thickness that corresponds to a maintenance time of maintenance for suppressing the cause when a detection state of the deposited material sensor changes from deposited material absent to deposited material present.

A vacuum pump includes a housing, a rotor cylindrical portion, and a stator cylindrical portion. The housing has an inlet port for sucking gas and an outlet port for discharging the sucked gas. The rotor cylindrical portion is housed in the housing. The stator cylindrical portion is housed in the housing, and is arranged to face the rotor cylindrical portion. A screw groove is formed on one of opposing surfaces of the stator cylindrical portion and the rotor cylindrical portion. The groove depth D of the screw groove is smaller at an end on an exhaust side than at an end on a suction side. The decrement of the groove depth D is greater on the suction side than on the exhaust side.

A turbo-molecular pump comprises: a turbine pump portion having rotor blades and stator blades arranged in multiple stages in an axial direction; a drag pump portion provided on a downstream side of the turbine pump portion; a case housing the turbine pump portion; a base housing the drag pump portion; and a temperature adjustment unit provided between the case and the base. The temperature adjustment unit includes a temperature adjustment spacer forming a pump casing together with the case and the base and, the temperature adjustment unit includes a cooler, a heater, and a temperature detector which are provided at the temperature adjustment spacer.

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.

In a vacuum pump, a portion of a lower end portion of a rotating cylindrical body is cut in an axial direction thereof to form an imbalance correction portion (removal portion). Preferably, the removal portion is formed so as to minimize an axial width of the rotating cylindrical body and set a circumferential width of the rotating cylindrical body to a value of not less than a thickness (width in a radial direction) of the rotating cylindrical body. Additionally, a corner formed in the removal portion is formed to have a large. With this configuration, in the rotating cylindrical body, the removal portion is formed to have a shape in which a removal width (depth) in the axial direction of the rotating cylindrical body is small and a removal width in the circumferential direction thereof is large.