A heating, ventilation, air conditioning, and refrigeration (HVACR) system includes a compressor with a gas bearing supplied with compressed gas and a controller. The controller is configured to determine an inlet pressure and outlet pressure of the gas bearing, determine a maximum speed limit based on the inlet pressure and the outlet pressure, and prevent the compressor from operating at a speed that is greater than the maximum speed limit. A method of controlling a compressor includes calculating a maximum speed limit based on an inlet pressure and an outlet pressure of the gas bearing. The method also includes in response to determining that a speed setting is greater than the maximum speed limit, adjusting operation of the compressor such that a speed of the compressor is at or below the maximum speed limit.

A heat transfer circuit includes a compressor, a condenser, an expander, and an evaporator that are fluidly connected together. The compressor includes a housing and a shaft rotatable relative to the housing to compress a working fluid received at a suction inlet, in which the shaft is supported by a gas bearing, and the gas bearing including a bearing housing having a fluid inlet and an outlet. A high pressure gas source is fluidly connected to the fluid inlet of the bearing housing for supplying high pressure fluid to the fluid inlet of the gas bearing such that the gas bearing supports the shaft when the shaft is rotating. A pressure reducer is connected to the outlet of the gas bearing is provided for reducing a vent pressure of the gas bearing.

An integrated ceiling device includes a housing retaining an electronic assembly, a heat sink having a central opening, a light source coupled onto the heat sink, the housing is coupled with and disposed at least partly above the heat sink, and a central vertical axis of the housing aligns or is in proximity with the central opening of the heat sink.

A self-cooling system includes at least one rotating component and a housing configured to enclose the at least one rotating component. The housing includes at least one inlet bore and at least one exhaust bore. The at least one exhaust bore is disposed radially outward from a radial position of the at least one inlet bore with respect to an axis of rotation of the at least one rotating. The at least one inlet bore and the at least one exhaust bore are positioned to establish a pressure differential configured to circulate a fluid into the at least one inlet bore, through the housing, and out the at least one exhaust bore. The system does not have any feature in addition to the at least one rotating component configured to drive the fluid into the at least one inlet bore, through the housing, and out the at least one exhaust bore.

A fluid machine includes: a shaft portion; a shroud surrounding the shaft portion and including an inside surface that forms a flow path-forming surface defining a flow path with the shaft portion; a first propeller rotatably provided in the flow path; a second propeller rotatably provided on a downstream side of the first propeller in the flow path; and a motor including a rotor that is fixed to an outer circumferential portion of the second propeller and that is accommodated in the shroud, and a stator that surrounds the rotor via a clearance and that is fixed in the shroud. A portion of the flow path-forming surface on a downstream side of the second propeller decreases in diameter toward the downstream side, and the shroud includes an inlet flow path that is open at a portion between the first propeller and the second propeller of the flow path-forming surface.

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 fluid circulator including a pump body with an impeller; an electric motor having a rotor connected to the impeller for rotatably driving the impeller; an end portion associated with the motor body for housing at least one electronic board for controlling the circulator. The end portion is monolithically cup-shaped lid fitted onto the motor body in substantial continuity therewith enclosing a housing compartment for said electronic board; an electronic power device mounted onto the electronic board so as to face the end wall of the cup-shaped lid; at least one portion of said end wall being recessed towards the electronic board and being externally provided with at least one cooling fin extending in parallel to the axis of the motor to constitute a heat sink; and a layer of a heat-conductive paste material in contact with the electronic power devices and recessed surface.

A vacuum pump capable of suppressing the solidification of gas in a normal operation of a pump is provided. Provided is a vacuum pump including a casing that has an inlet port for sucking gas from outside and an outlet port for exhausting the gas to the outside; a turbo-molecular-pump mechanism that is disposed in the casing and includes rotor blades and stator blades alternately arranged in multiple stages in an axial direction; a thread-groove-pump mechanism that is disposed in the casing and is connectedly disposed on an exhaust side of the turbo-molecular-pump mechanism; first temperature regulating means that is configured to regulate cooling of the turbo-molecular-pump mechanism; and second temperature regulating means that is configured to regulate heating of the thread-groove-pump mechanism.

A vacuum pump which suppresses occurrence of deposition caused by an exhaust gas is obtained. The vacuum pump includes: a pump portion including a shaft portion, a rotor disposed on an outer peripheral side of the shaft portion, and a stator disposed on the outer peripheral side of the rotor; a channel of the exhaust gas from the pump portion to an outlet port; and a shielding portion which suppresses contact of the exhaust gas with the shaft portion in the channel. Further, an end portion of the shielding portion has a surface opposed to the rotor.

The present invention provides a centrifugal pump for heating fluid by eddy current comprising a volute (29) and a cover (34), in which internally regarding the volute (29) there are provided: an impeller (33) positioned between two supporting annular disks (32) of magnets each comprising a plurality of permanent magnets (31); and two armatures (30) positioned at the ends of the internal assembly. In addition, the invention also provides a subsea tool for fluid heating by eddy current comprising: a centrifugal pump (1) driven by a hydraulic motor (3) by means of a shaft (11); a fluid storage tank (2) hydraulically connected to the centrifugal pump (1); at least one piloted on-off valve (4); piloted directional valves (12, 13); and a filter (7) hydraulically connected to the centrifugal pump (1).