Provided is a vacuum pump regarding which compression can be improved at low costs.

Included is a plurality of Siegbahn exhaust mechanisms in which a helical groove is provided to a stator disc. The Siegbahn exhaust mechanisms are provided on both faces of an upstream side and a downstream side of the stator disc. An end portion of the helical groove provided on the upstream side and a start portion of the helical groove provided on the downstream side are situated at least partially overlapping in a circumferential direction. A width of a channel of a switchback portion of the upstream side and the downstream side is equivalent or less than a depth of a channel of the Siegbahn exhaust mechanisms.

An electric blower includes a motor unit, a shaft, a centrifugal impeller, a fan cover, a motor unit case, and a bracket located away from centrifugal impeller and toward motor unit in a direction in which a central axis of the shaft extends. The bracket includes a first portion located outward of the vent in a radial direction, and a second portion located outward of the first portion and outward of an outer circumference of the motor unit case in the radial direction. A first airflow passage and a second airflow passage are formed in the bracket, the first and second airflow passages communicate with an airflow passage formed by the centrifugal impeller and the fan cover.

The water-conserving liquid ring vacuum pump system receives the output from a water ring vacuum pump, removes the air and contaminants from the water, and returns the clean water to the make-up water port on the pump, thereby saving most of the water that would normally be discarded. Friction in the pump also heats the water, so the system is designed to cool the water as well.

A vacuum pump generally comprises a low pressure portion and a high pressure portion separated by a gas impermeable partition. Gas molecules exit the low pressure portion through an opening in the partition and passively impinge on a featureless rotatable surface in the high pressure portion. A drive rotates the rotatable surface with tangential velocity in the supersonic range at multiple times the most probable velocity of the impinging gas molecules. Impinging gas molecules are ejected outwardly from the periphery of the rotatable surface generating a substantial net outward flow of gas and reducing the pressure in the low pressure portion. The vacuum pump is effective to reduce the pressure in the low pressure portion to a target minimum pressure without using seals to prevent gas molecules from leaking back to the low pressure portion and without using blades or vanes to actively impact the gas molecules.

The present disclosure provides a vacuum pump with which size and weight reduction, improvement of workability, and cost reduction can be realized. Electrical connection between a pump main body that has a rotor supported by a magnetic bearing and a control unit that controls the drive of the pump main body is established by a flexible printed wiring board configured by printing an electric circuit on a surface of a sheet-like insulating substrate.

The present invention provides an energy-efficient method and apparatus that can achieve exhaust gas abatement with a minimum use of diluent nitrogen gas. More specifically, the present invention is directed to a method and apparatus for exhaust gas abatement under reduced pressure, in which an exhaust gas supplied from an exhaust gas source via a vacuum pump is decomposed by heat of a high-temperature plasma under a reduced pressure.

A roadway or pavement sweeper with multiple sweeping modes for the removal of debris from a swept surface may, in some embodiments, include a sweeper vehicle having a pair of side-brooms independently movable between a retracted and extended position for sweeping debris into an area therebetween and at least one material-transfer broom to sweep a portion of the debris accumulated between the side-brooms as the vehicle moves in its direction of travel. A fan-driven suction-inlet may be provided at or adjacent each side of the vehicle. The at least one material-transfer broom may rotate in a first or other direction to transfer debris for entrainment into a selected suction-inlet for transfer to a debris hopper. Other embodiments are also described.

A vacuum pump system comprising a main vacuum pump that is connected to a chamber that is to be evacuated. An auxiliary pump is connected to an outlet of the main vacuum pump. Furthermore, a sealing gas supply device is connected to the main vacuum pump. The sealing gas supply device is switched on and off with the aid of a control device as a function of a predetermined control variable. Additionally, a method for controlling the vacuum pump system.

Provided are a vacuum pump and an adapter used in the vacuum pump that are capable of responding to various changes in specifications at low cost. A turbo-molecular pump includes a base, a stator blade that is provided above the base in an axial direction of a rotor, a rotor blade that is integrally attached to the rotor, a housing that is formed in a cylindrical shape, and accommodates the stator blade and is integrally attached to the base, and an adapter that is replaceable depending on a type of the stator blade, the rotor blade, or the housing, and that is detachably mounted on the base and is configured to support the stator blade in the axial direction.

A vacuum pump generally comprises a low pressure portion and a high pressure portion separated by a gas impermeable partition. Gas molecules exit the low pressure portion through an opening in the partition and passively impinge on a featureless rotatable surface in the high pressure portion. A drive rotates the rotatable surface with tangential velocity in the supersonic range at multiple times the most probable velocity of the impinging gas molecules. Impinging gas molecules are ejected outwardly from the periphery of the rotatable surface generating a substantial net outward flow of gas and reducing the pressure in the low pressure portion. The vacuum pump is effective to reduce the pressure in the low pressure portion to a target minimum pressure without using seals to prevent gas molecules from leaking back to the low pressure portion and without using blades or vanes to actively impact the gas molecules.