1701results about "Compressor" patented technology

The present invention relates to compositions for use in refrigeration, air-conditioning, and heat pump systems wherein the composition comprises a tetrafluoropropene and at least one other component. The compositions of the present invention are useful in processes for producing cooling or heat, as heat transfer fluids, foam blowing agents, aerosol propellants, and fire suppression and fire extinguishing agents.

A method for increasing circulation in a breathing person utilizes a valve system that is interfaced to the person's airway and is configured to decrease or prevent respiratory gas flow to the person's lungs during at least a portion of an inhalation event. The person is permitted to inhale and exhale through the valve system. During inhalation, the valve system functions to produce a vacuum within the thorax to increase blood flow back to the right heart of the person, thereby increasing cardiac output and blood circulation.

An outer end of a seal element for a fixed scroll is extended to a position close to an end of an inside spiral wall of the fixed scroll, and an outwardly extended portion is formed at an outer periphery of a disc-shaped base plate of a movable scroll, so that a bottom surface of the movable scroll is always kept in a sliding contact entirely with the seal element during the orbital movement of the movable scroll. A thickness of the outwardly extended portion formed at the outer periphery of the disc-shaped base plate is made smaller than that of the disc-shaped base plate, so that the weight of the fluid machine can be smaller.

A facial mask includes a mask body that is adapted to be coupled to a patient's face. A valve system is coupled to the mask body to permit the inflow of respiratory gasses into the mask body and to permit the outflow of respiratory gasses from the mask body. A metronome is coupled to the mask body to produce a repeating chest compression signal to facilitate the performance of regular chest compressions when performing cardio pulmonary resuscitation. The metronome may also produce a ventilation signal to facilitate the proper ventilation of the patient.

A turbo-compressor (TC) system for extracting energy from an aircraft engine. The TC system has a TC assembly with a turbine mechanically coupled to at least one compressor. The TC system has a TC inlet in fluid communication with a bleed air system in the aircraft engine and a TC outlet in fluid communication with an air conditioning (AC) pack of an aircraft air conditioning system and configured to extract reduced temperature pack inlet air from the TC assembly into the air conditioning pack. The TC system has a ram air inlet coupled to the at least one compressor. The TC system has a TC control valve, and a TC check valve or a TC shutoff valve, both coupled to the TC assembly via a plurality of connective ducts. The TC system extracts energy from the bleed air to reduce bleed air flow and AC pack ram air usage.

A method is provided for protecting a refrigerant vapor compression system during a standstill period following shutdown of the refrigerant vapor compression system. A method is provided for detecting a low refrigerant charge level in a refrigerant vapor compression system operating in a transcritical mode. A refrigerant vapor compression system is provided that includes a controller operative to perform a refrigerant charge detection method.

A control method and apparatus for critical rotational speed avoidance in a compressor-expander set in a gas refrigeration system. By varying an opening of an antisurge or recycle valve, a shaft power used by the compressor in the compressor-expander set may be varied, thereby varying the rotational speed of the compressor-expander set to move it away from its critical speed zone. Additionally, a feedforward signal may be provided by a compressor-expander set control system to cause an antisurge valve for a recycle compressor to open upon a trip or shutdown of one compressor-expander set.

A cooling system for an electrical motor or generator includes a first cooling loop, a second cooling loop, and a heat exchange system. The first cooling loop may extract heat from an iron stack and winding of the electrical motor or generator. The second cooling loop may extract heat from end turns of the stator winding, the rotor, and the bearings independently from and simultaneously to the first cooling loop. At least the first cooling loop may pass through the heat exchange system. A liquid coolant may circulate in the first cooling loop and a compressed gas, such as compressed air or compressed refrigerant in vapor form, may circulate in the second cooling loop. The cooling system and method for an electrical motor or generator may be suitable for, but not limited to, applications in the aircraft and aerospace industries, such as driving a cabin air compressor of an aircraft.

In an ejector cycle having an ejector for decompressing refrigerant, a check valve is disposed in an oil return passage through which refrigerant including a lubrication oil is introduced from a refrigerant outlet side of an evaporator to a refrigerant suction side of a compressor while bypassing the ejector. When the lubrication oil amount staying in the evaporator reduces, the check valve is automatically closed, and a normal operation mode of the ejector cycle is automatically set. On the contrary, when a large amount of lubrication oil stays in the evaporator, the check valve is automatically opened, and an oil return mode is automatically set. Therefore, the lubrication oil staying in the evaporator can be controlled equal to or lower than a predetermined amount, thereby effectively returning the lubrication oil to the compressor.

A refrigerant vapor compression system includes a flash tank disposed in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger. The flash tank has a shell defining an interior volume having an upper chamber, a lower chamber and a middle chamber. A first fluid passage establishes fluid communication between the middle chamber and the upper chamber and a second fluid passage establishing fluid communication between the middle chamber and the lower chamber. An inlet port opens to the middle chamber. A first outlet port opens to the upper chamber and a second outlet port opens to the lower chamber.

A plurality of scroll compressors with different fixed volume indexes are connected in fluid parallel circuit and configured to selectively operate to maximize isentropic efficiency at different condensing temperatures. Different quantities of scroll compressors of different volume indexes may be selected based upon typical climate or geographic location environmental conditions to attempt to maximize efficiency. A controller may selectively operate different combinations of the compressors of different volume indexes bases up load demands and condensing temperature conditions, which may be determined in a variety of ways.

In a heat-pump water heater with a super-critical refrigerant cycle, a valve open degree of a decompression valve is controlled to control a pressure of high-pressure side refrigerant so that a temperature difference between refrigerant flowing out from the water-refrigerant heat exchanger and water flowing into a water-refrigerant heat exchanger is set in a predetermined temperature range. Thus, the pressure of high-pressure side refrigerant in the super-critical refrigerant cycle can be controlled, thereby suitably adjusting heat-exchange performance of an internal heat exchanger, and restricting the temperature of refrigerant discharged from the refrigerant compressor from being uselessly increased.

The invention discloses an air conditioner and an oil return control method and device thereof. The oil return control method includes the steps of judging whether the operation condition of the air conditioner meets a preset condition which is used for triggering the air conditioner to start an oil return program, and controlling the air conditioner to start the oil return program under the condition that the operation condition of the air conditioner is judged to meet the preset condition so that oil return operation, at least comprising increasing of the operation frequency of a compressor of the air conditioner, can be executed. The technical problems that in the prior art, due to improper oil return of the compressor, the lubricating effect is poor, and abrasion of the compressor is high are solved.

An apparatus for controlling an operation of a compressor includes: a back electromotive force calculator for calculating a back electromotive force of a compressor based on a value of a current applied to a motor of the compressor and a value of a voltage applied to the motor of the compressor; an operation frequency reference value determining unit for detecting a mechanical resonance frequency of the compressor based on the back electromotive force value and the current value and determining the detected mechanical resonance frequency as an operation frequency reference value; and a controller for varying an operation frequency of the compressor according to the determined operation frequency reference value.

A two-stage vapor cycle compressor includes a first stage impeller, a second stage impeller situated adjacent to the first stage impeller, an electric motor running on a pair of foil bearings, a thrust disk including two foil bearings and being positioned between the second stage impeller and the electric motor, and a compressor housing enclosing the first and second stage impeller and the electric motor. A refrigerant vapor compressed by the first stage and second stage impeller flows through an internal passageway formed by the compressor housing and cools the foil bearings and the electric motor. The compressor may be a gravity insensitive, small, and lightweight machine that may be easily assembled at low manufacturing costs. The two-stage vapor cycle compressor may be suitable for, but not limited to, applications in vapor compression refrigeration systems, such as air-conditioning systems, for example, in the aircraft and aerospace industries.

A refrigerant vapor compression system includes a flash tank economizer defining a separation chamber is disposed in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger. A primary expansion valve is interdisposed in the refrigerant circuit in operative association with and upstream of the refrigerant heat absorption heat exchanger and a secondary expansion valve is interdisposed in the refrigerant circuit in operative association and upstream of the flash tank economizer. A refrigerant vapor injection line establishes refrigerant flow communication between an upper portion of the separation chamber and an intermediate pressure stage of the system's compression device and a suction pressure portion of the refrigerant circuit. A refrigerant liquid injection line establishes refrigerant flow communication between a lower portion of said separation chamber and an intermediate pressure stage of the compression device and a suction pressure portion of the refrigerant circuit.

The invention provides a method and a system for low-frequency oil return control for an air conditioner. The method comprises the following steps: detecting a running frequency, a suction gas superheat degree, an indoor environment temperature and an outdoor environment temperature of a compressor; when detecting that the running frequency of the compressor is kept for a preset time in the case that the running frequency is lower than a preset oil return frequency, enabling the air conditioner to enter an oil return mode, selecting an initial openness degree of an electronic expansion valve in the air conditioner, an initial rotational speed of an outdoor fan and an initial rotational speed of an indoor fan according to the indoor environment temperature and the outdoor environment temperature, adjusting the openness degree of the electronic expansion valve to be the initial openness degree, adjusting the rotational speed of the outdoor fan to be the initial rotational speed, and adjusting the rotational speed of the indoor fan to be the initial rotational speed; and adjusting the openness degree of the electronic expansion valve, the rotational speed of the outdoor fan and the rotational speed of the indoor fan according to the detected suction gas superheat degree. According to the invention, an oil return effect is achieved by virtue of a pipeline pressure difference, and various adverse factors brought by the traditional increasing-frequency oil return are overcome in case of no influence on the refrigerating capacity need and the running reliability of low-frequency running.

A multi-compressor heat pump system configured to provide heating and cooling over a range of ambient temperatures. The compressors can be operated independently and alone or together in series for maximum output. Heat exchangers are selectively fluidically connected to the compressors to enable refrigerant flow between the compressors and at least two heat exchangers in a manner that enables the heat pump system to be selectively operable in various modes. Preferred aspects include selectively operating the compressors based on the ratio of the evaporating and condensing pressures of the refrigerant within the heat pump system, a mixing chamber between the compressors, and a lubricant management system to prevent the accumulation of a lubricant in one of the compressors.

A cooling apparatus for cooling a heat-generating member includes a cooling flow path, a condenser, a coolant-returning flow path, a first check valve and a second check valve. The cooling flow path is thermally connected to the heat-generating member. The condenser is connected to a downstream portion of the cooling flow path and condenses a coolant contained in the cooling apparatus after the coolant is evaporated in the cooling flow path. The coolant-returning flow path returns the coolant condensed by the condenser to an upstream portion of the cooling flow path. The first check valve is disposed between the coolant-returning flow path and prevents the coolant from flowing in a reverse direction from the cooling flow path to the first coolant-returning flow path. The second check valve is disposed between the condenser and the coolant-returning flow path and prevents the coolant from flowing in a reverse direction from the first coolant-returning flow path to the condenser.

A cooling device, in particular for a switchgear cabinet with a housing, in which a refrigeration cycle system is housed, wherein the refrigeration cycle system has vibration-generating elements, namely a compressor and at least one fan. The fan and the compressor are supported in the housing via vibration dampers. For preventing vibratory emissions a cooling device in accordance with this invention has the fan and/or the compressor separately supported by first vibration dampers on an intermediate bracket, or together on an intermediate bracket. The intermediate bracket is supported by second vibration dampers on a bracket, and the bracket is connected to the housing.

The invention discloses an oil returning method during heating of a multi-split air-conditioning unit. The oil returning method comprises the following steps of: a, carrying out normal heating on the multi-split air-conditioning unit; b, adjusting an operation frequency of a compressor (1) to an oil returning frequency, adjusting aperture of an external unit electronic expansion valve (2) to an external unit oil returning aperture, adjusting apertures of internal unit electronic expansion valves (3) of all the indoor units to an internal unit oil returning aperture, and returning oil for 2.5-3.5 minutes by maintaining the oil returning frequency of the compressor (1), the external unit oil returning aperture of the external unit electronic expansion valve (2) and the internal unit oil returning aperture of the internal unit electronic expansion valves (3); c, adjusting the operation frequency of the compressor (1) to a normal frequency, and operating for 15-25 seconds; and d, adjusting the aperture of the external unit electronic expansion valve (2) to the normal aperture, and adjusting the apertures of all the internal unit electronic expansion valves (3) to the normal aperture. The oil returning method disclosed by the invention can guarantee good oil returning effect without liquid impact on the compressor, and indoor heating can be continuously carried out in an oil returning process.

A high efficiency, low maintenance single stage or multi-stage centrifugal compressor assembly for large cooling installations. A cooling system provides direct, two-phase cooling of the rotor by combining gas refrigerant from the evaporator section with liquid refrigerant from the condenser section to affect a liquid/vapor refrigerant mixture. Cooling of the stator with liquid refrigerant may be provided by a similar technique. A noise suppression system is provided by injecting liquid refrigerant spray at points between the impeller and the condenser section. The liquid refrigerant may be sourced from high pressure liquid refrigerant from the condenser section.

Provided is a method for selecting a lubricant and a refrigerant for use in a vapor-compression refrigeration device such that the combination of the lubricant and refrigerant produces a fluid system having a lubricant-rich phase and a refrigerant-rich phase, yet exhibits miscible-type properties.

The invention relates to a high-precision constant-temperature and humidity air conditioner operated in a wide temperature range. The air conditioner comprises an outdoor machine and an indoor machine, wherein the outdoor machine is provided with a condenser and a condensing fan; the indoor machine comprises an evaporator, a thermal recovery exchanger, an electric heater, a humidifier and a blower; and a compressor is formed by connecting in parallel a constant-frequency compressor and a variable-frequency compressor (or a digital scroll compressor) and is arranged in the indoor machine. As the system adopts frequency conversion technology or digital vortex technology and electronic expansion valve technology and unique classified evaporator control, condenser fan frequency-conversion control technology and evaporator frostless structural design, the air condition broadens the use environment range, indoor temperature control environment (between 7 and 30 DEG C) and relative humidity control environment (between 35 and 70 percent RH), can be reliably operated in the outdoor high-temperature environment of 45 DEG C, also improves the controlling precision of indoor temperature and humidity, and is applicable to places with severe requirements on temperature and humidity and large environmental temperature change.

An external heat exchanger is used to transfer heat from a compressor lubricant to an expanded working fluid, thereby cooling the lubricant. The heat exchanger may also be used to sub-cool condensed working fluid with the same flow of expanded working fluid. A horizontal scroll-type compressor includes an intermediate lubricant sump between a main bearing support and a scroll member. A counterweight on the crankshaft can travel through the lubricant in the intermediate sump to splash the lubricant around. A horizontal scroll-type compressor can include multiple machined surfaces that are utilized to precisely center and align components of the compressor.

A vapor compression system includes a timer and a controller for periodically starting up the system during the off-season periods (primarily non-cooling months) in which the system would normally be shut down. This provides periodic lubrication to the compressor components and prevents severe flooded starts due to excessive accumulation of refrigerant in the compressor (compressor oil sump in particular) and other system components. Provision is also made to sequentially turn on and off system components such as the compressor, the evaporator fan and the condenser fan to enhance the system operation. The timing sequences are provided for the time intervals between the startups, as well as the off-season operation cycle times.

The invention relates to a process for cooling or heating a fluid or a body by means of a vapour compression circuit comprising a centrifugal compressor and containing a heat-transfer fluid, the heat-transfer fluid comprising at least two compounds selected from 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene, 1,1,1,2-tetrafluoropropene, 1,1-difluoroethane and 3,3,3-trifluoropropene, in which: the ratio of the Mach number of the centrifugal compressor to the Mach number which the centrifugal compressor has under the same operating conditions if the heat-transfer fluid is replaced with 1,1,1,2-tetrafluoroethane in the vapour compression circuit is greater than or equal to 0.97 and less than or equal to 1.03; the compression ratio of the centrifugal compressor is less than or equal to the compression ratio which the centrifugal compressor has under the same operating conditions if the heat-transfer fluid is replaced with 1,1,12-tetrafluorethane in the vapour compression circuit. The invention also relates to equipment suitable for implementing this cooling or heating process, and also to a process for converting existing equipment.

The invention discloses a method and a device of oil return control of an air conditioner and the air conditioner. The method of the oil return control of the air conditioner comprises the following steps: detecting flow velocity v of refrigerating fluid in an oil return pipe, comparing the flow velocity v with preset flow velocity v <min>, wherein the preset flow velocity v <min> is the minimum flow velocity which is needed when the air conditioner returns oil; and when the flow velocity v is judged to be smaller than or equal to the flow velocity v <min>, the air conditioner is controlled to carry out an oil return treatment. By the adoption of the method and the device of the oil return control of the air conditioner and the air conditioner, the problem that when the refrigerating fluid operates in slow speed, a compressor is easy to damage caused by fuel starvation in the prior art can be solved, so that the effect that the service life of the compressor is prolonged is achieved.

In a refrigerant cycle system for a vehicle air conditioner, when a continuous operation time of a compressor elapses a predetermined time after the compressor operates, operation of the compressor is forcibly interrupted so that a refrigerant pressure at a suction side of the compressor is changed. Thus, even when the compressor operates continuously in a long time when only a front evaporator operates among front and rear evaporators, the refrigerant pressure at a low-pressure side is forcibly changed so that a rear thermal expansion valve of the rear evaporator is forcibly opened. As a result, lubrication oil staying in the rear evaporator and a low-pressure pipe is introduced into the suction side of the compressor by a refrigerant flow due to a valve opening of the rear thermal expansion valve of the rear evaporator.

A CO2 compressor is disclosed for forcing and moving a lubricant under discharge pressure. If the oil path is reduced in size or a pressure reducing part is inserted to handle the large differential pressure caused between the discharge pressure and the intake pressure, the oil path would become liable to be easily clogged by foreign matter. In view of this, an intermittent oil supply mechanism is formed in the oil path using the sliding contact portion between a fixed member of the compressor body and a movable member. Thus, the substantial lubrication time period is shortened and the amount of oil supplied is limited.