A heating device for heating a component in a turbo molecular pump for exhausting a gas includes a heat transfer member, a heater, a first seal member and a second seal member. The heat transfer member is provided in an opening of a housing of the turbo molecular pump and has one end fixed to the component and the other end exposed to an outside. The heater in the heat transfer member heats the component through the heat transfer member. The first seal member is provided between the heat transfer member and the opening along an outer peripheral surface of the heat transfer member. The second seal member between the heat transfer member and the opening is located close to the component compared to the first seal member. The second seal member suppresses movement of radicals in a gas into a space between the heat transfer member and the opening.

An exhaust pump includes: a cylindrical rotating member; an outer cylindrical fixed member; an inner cylindrical fixed member a helical inner thread groove exhaust passage provided between the cylindrical rotating member and the inner cylindrical fixed member; connecting opening portions that are opened in the cylindrical rotating member and that lead a part of gas existing in the vicinity of the outer periphery of the cylindrical rotating member towards the inner thread groove exhaust passage. A gap between an upstream end of the connecting opening portions and lowermost stage rotor blades provided at the outer periphery of the cylindrical rotating member which is located upstream of the connecting opening portions has a dimension equal to or greater than a dimension that enables insertion, into the gap, of a tool for opening the connecting opening portions.

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 vacuum pump comprising a turbomolecular stage and a drag stage, the vacuum pump comprising a stator and a rotor. The rotor comprises a turbomolecular rotor and a drag rotor attached together. The turbomolecular rotor comprises a hub from which a plurality of blades extend, the hub comprising a mounting portion for mounting to a spindle of a motor and a hollow cylindrical portion, the hollow cylindrical portion extending from the mounting portion towards an outlet end of the turbomolecular stage. The drag rotor comprises a cylindrical skirt and an attachment part extending away from the cylindrical skirt, the attachment part extending within the hollow cylindrical portion of the hub of the turbomolecular rotor and being attached thereto at a point that is closer to the mounting portion than to the outlet end of the turbomolecular rotor.

A deposit detection device for an exhaust pump is provided, which can be easily put into operation without the burdens of, for example, installing equipment for flowing a gas, or adding or changing operation modes in apparatuses. The device is configured to include: a means for detecting motor current values a motor that rotates a rotating body; a current value storage portion that stores only motor current values that are equal to or greater than a preset value from among detected motor current values; an average value calculation portion that calculates an average value per unit time of the stored motor current values; an average value storage portion that stores the calculated average value; an approximation calculation portion that determines a linear approximation of the stored chronologically ordered average values; and a difference value calculation portion that determines a difference value between a predicted motor current value calculated by using the linear approximation and an initial motor current value at a start of use of the exhaust pump. A time when the difference value exceeds a predetermined threshold is determined as a time for maintenance of the exhaust pump.

Provided are a vacuum pump and a method for the vacuum pump in which, when contact between a rotating body and a stator is sensed, the cause of the contact can be analyzed. Contact determination is made using a threshold for rotating body contact determination for a displacement signal and a threshold for rotating body contact determination for an acceleration signal. The amount of unbalance of a rotating body is determined using a threshold for amount-of-unbalance increase determination for the displacement signal and a threshold for amount-of-unbalance increase determination for the acceleration signal. When, in one of the displacement signal and the acceleration signal, the threshold for amount-of-unbalance increase determination or the threshold for amount-of-unbalance increase determination is exceeded within a predetermined time before determination of an estimated time point of contact, the contact is determined not to be caused by an increase in accumulation of products.

A turbo-molecular pump comprises: a rotor; stationary blades; a stator; a plurality of spacers; a heater disposed on the base; a temperature sensor for detecting a temperature of the stator; and a temperature regulation section for on/off controlling the heater based on a temperature detected by the temperature sensor to regulate the temperature of the stator so as to be a reaction product accumulation prevention temperature. At least one spacer arranged on a base side of the plurality of spacers is cooled by coolant, and the turbo-molecular pump further comprises a heat insulation member disposed between the base and the spacer arranged on the base.

A leak detector for checking the sealing tightness of an object to be tested includes a detection inlet to be connected to the object, a first pumping device, and a gas detector. The first pumping device includes a first rough vacuum pump, at least one second rough vacuum pump, and a turbomolecular pump. The gas detector is connected to the turbomolecular pump. The outlet of the at least one second rough vacuum pump is connected to the first rough vacuum pump, between two in-series pumping stages of the first rough vacuum pump.

The present invention provides a vacuum pump that measures the temperature of a rotating portion accurately and at low cost, a stator column of the vacuum pump, a base, and an exhaust system of the vacuum pump at low cost. The vacuum pump according to the present embodiment, the thread groove-type seal for causing some of the purge gas to flow back toward the temperature sensor unit is provided on the downstream side of the purge gas flow path in which the temperature sensor unit is disposed, thereby increasing the pressure of the purge gas in the vicinity of the temperature sensor unit. Thus, with the small amount of purge gas, the gas pressure around the temperature sensor unit can create an intermediate flow or a viscous flow. Consequently, the total amount of purge gas to be supplied can be saved, resulting in cost reduction.

Provided is a vacuum component capable of evacuation by a getting effect, which has a large maximum number of captured molecules and a long working life. It is provided, in an area around its central axis, with a hollow cylindrical electrode 20 having an electrode surface 20A that is sufficiently smaller than an inner surface 10A of the vacuum container 10, along the central axis. In the vacuum container 10, it is possible to realize any one of states among a first state of generating DC discharge by introducing Ar into the inside and setting the electrode surface 20A at a positive potential, a second state of setting the electrode surface 20A at a ground potential without introducing Ar, and a third state of generating DC discharge by introducing Ar into the inside and setting the electrode surface 20A at a negative potential. Evacuation by the vacuum component 1 is performed in the second state. Further, evacuation by the vacuum component 1 is performed also by realizing a state of performing a heating process at 400° C. or below without using the electrode.