Abstract: A refrigerant system providing enhanced performance over a wider range of operating conditions than traditional economized refrigerant systems. The system includes an economizer branch that connects a liquid outlet from a suction accumulator to an economizer inlet port of a compressor unit. The economizer branch includes a liquid refrigerant pump that delivers a non-evaporated liquid refrigerant portion from the suction accumulator into the economizer heat exchanger, where the liquid refrigerant portion evaporates, increasing thermodynamic potential of the main circuit refrigerant also flowing in through the economizer heat exchanger, and a formed vapor stream is delivered into the economizer inlet port of the compressor unit.

Abstract: CO2 refrigeration circuit (2) for circulating a refrigerant in a predetermined flow direction, comprising in flow direction a heat-rejecting heat exchanger (4), a receiver (10) having a liquid portion (12) and a flash gas portion (14), and subsequent to the receiver (10) a medium temperature loop (20) and a low temperature loop (24), wherein the medium and low temperature loops (24) each comprise in flow direction an expansion device (26, 28), an evaporator (30, 32) and a compressor (46, 38), the refrigeration circuit (2) further comprising a liquid line (16) connecting the liquid portion (12) of the receiver (10) with at least one of the medium and low temperature loops (20, 24) and having an internal heat exchanger (54), and a flash gas line (50) connecting the flash gas portion (14) of the receiver (10) via the internal heat exchanger (54) with the inlet of the low temperature compressor (46), wherein the internal heat exchanger (54) transfers in use heat from the liquid flowing through the liquid line (16

Abstract: A sub-engine (30), a compressor (40) driven by the sub-engine (30), and a refrigeration circuit (70) connected to the compressor (40) and operable in a vapor compression refrigeration cycle are provided, and the interior of a refrigerator (13) of a refrigerated vehicle (10) is cooled. A rotational speed control unit (91) for linearly controlling fluctuations in the rotational speed of the sub-engine (30) such that the refrigeration capacity grows or declines in response to a refrigeration load is provided. A battery (51) for storing electric power and an electric generator (50) for generating electric power by the rotational drive of the refrigerating engine (30) to store the generated electric power in the battery (51) are provided. A fan motor (7a) for the refrigeration circuit (70) is selectively connectable to the electric generator (50) and the battery (51) such that power is fed from one of the electric generator (50) and the battery (51) to the fan motor (7a).

Abstract: An air conditioner is provided with a refrigerant circuit and an operation controller. The refrigerant circuit includes a heat source unit, a refrigerant communication pipe, an expansion mechanism, and a utilization unit. The heat source unit has a compression mechanism and a heat source side heat exchanger. The heat source unit is connected to the refrigerant communication pipe. The utilization unit has a utilization side heat exchanger and is connected to the refrigerant gas communication pipe. The operation controller performs an oil-return operation in advance for returning oil pooled in the refrigerant circuit when a refrigerant quantity judging operation is carried out for judging the refrigerant quantity inside the refrigerant circuit.

Abstract: A multi-stage refrigeration system is provided. The refrigeration system includes a first compression element which produces a first compressed refrigerant stream. A mixer combines the first compressed refrigerant stream with an auxiliary refrigerant stream. A second compression element is coupled to the mixer and produces a second compressed refrigerant stream. A first heat exchanger receives the second compressed refrigerant stream and generates a cooled stream. A stream splitter receives the cooled stream and provides first and second output streams. A first expansion valve receives the first output stream and controls the flow of the first output stream and a second expansion valve receives the second output stream and controls the flow of the second output stream. A second heat exchanger generates the auxiliary refrigerant stream provided to the mixer.

Abstract: A transcritical vapor compression system includes a fluid circuit circulating a refrigerant in a closed loop. The fluid circuit has operably disposed therein, in serial order, a first compressor, an intercooler, a second compressor with a variable capacity, a first heat exchanger, an expansion device and a second heat exchanger. The first compressor compresses the refrigerant from a low pressure to an intermediate pressure. The second compressor compresses the refrigerant from the intermediate pressure to a supercritical pressure. The first heat exchanger is positioned in a high pressure side of the fluid circuit. The second heat exchanger is positioned in a low pressure side of the fluid circuit. The expansion device reduces the pressure of the refrigerant from a supercritical pressure to a relatively lower pressure. Cooling means cools the refrigerant within one of the compressors.

Abstract: A refrigeration system includes a primary compressor that receives refrigerant from an evaporator and delivers refrigerant to a condenser, a subcooling compressor that delivers refrigerant to the condenser, and a subcooler that receives refrigerant from the condenser. A first refrigerant flow path and a second refrigerant flow path pass through the subcooler. The first refrigerant flow path delivers a portion of the refrigerant to the evaporator, and the second refrigerant flow path delivers a remainder of the refrigerant to the subcooling compressor. The refrigeration system includes a controller operable to control operation of the subcooling compressor such that the refrigeration system operates at a point of highest efficiency.

Abstract: An economized refrigerant vapor compression system (10) for water heating includes a refrigerant compression device (20), a refrigerant-to-water heat exchanger (30), an economizer heat exchanger (60), an evaporator (40) and a refrigerant circuit (70) providing a first flow path (OA, 70B, 70C, 70D) connecting the compression device (20), the refrigerant-to-liquid heat exchanger (30), the economizer heat exchanger (60) and the evaporator (40) in refrigerant circulation flow communication and a second flow path (70E) connecting the first flow path (62) through the economizer heat exchanger (60) to the compression device (20). The economizer heat exchanger (60) has a first pass (62) for receiving a first portion of the refrigerant having traversed he refrigerant-to-liquid heat exchanger and a second pass (64) for receiving a second portion of the refrigerant having traversed the refrigerant-to-liquid heat exchanger.

Abstract: A multi-stage operation type air conditioner which can be operated in various cooling or heating capacities. The multi-stage operation type air conditioner includes a first discharge port, a first opening/closing device for opening or closing the first discharge port, a second discharge port having a size different from that of the first discharge port, a second opening/closing device for opening or closing the second discharge port, and a controller for controlling the air conditioner such that the air conditioner may be operated with one of the first and second discharge ports opened, in an operation with a lower cooling or heating load, and the air conditioner may be operated with both the first and second discharge ports opened, in an operation with a higher cooling or heating load.

Abstract: A refrigerant system is provided with tandem compressors. A tandem compressor arrangement includes at least two compressors operating in parallel and having at least one common manifold. A control may operate the compressors either simultaneously, or in some predetermined sequence to provide control over refrigerant system capacity. At least one of the tandem compressors is provided with a pulse width modulation control on a suction line. In this manner, the amount of refrigerant, compressed by the compressor, can be precisely controlled to exactly meet thermal load demands in the conditioned space.

Abstract: A refrigeration system (10) includes: a refrigerant circuit (15) including a low-pressure stage compressor (21) variable in displacement and a high-pressure stage compressor (31) variable in displacement and operating in a two-stage compression refrigeration cycle; and a controller (100) for controlling the operation of the refrigeration system (10). The controller (100) includes a first control section (101) and a second control section (102). The first control section (101) controls the operating capacity of the low-pressure stage compressor (21) to adapt to the load of the refrigeration capacity.

Abstract: This invention relates to a method and an apparatus for a modulating air conditioning system having increased energy efficiency and greater turndown capabilities. A modulating air conditioning system includes modulating at least one of the following components: a compressor, a compressor driver, a condenser fan, an evaporator fan, an effective evaporator surface area, an effective condenser surface area and/or an expansion device.

Abstract: Disclosed are a reciprocating compressor and a refrigerator having the same. The reciprocating compressor comprises a casing, one reciprocating motor mounted at a frame unit provided in the casing for generating a linear-reciprocation driving force, a first compression unit for compressing a refrigerant directly sucked without passing through the inside of the casing by receiving the driving force of the reciprocating motor, and a second compression unit for mixing a refrigerant introduced into the casing and a refrigerant discharged from the first compression unit and then compressing the mixed refrigerant once more by receiving the driving force of the reciprocating motor. Accordingly, a refrigerant is consecutively compressed two times, components are simplified, and the compressor is easily controlled. Also, the refrigerator having the reciprocating compressor decreases a load of the reciprocating compressor thereby to enhance the efficiency of the refrigerator.

Abstract: An air conditioner refrigerant circuit performs a cooling operation in which an outdoor heat exchanger functions as a condenser of the refrigerant compressed in a compressor and an indoor heat exchanger functions as an evaporator of the refrigerant condensed in the outdoor heat exchanger. Further, an outdoor expansion valve is disposed at a position that is at once downstream of the outdoor heat exchanger and upstream of a liquid refrigerant communication pipe in the refrigerant flow direction in the refrigerant circuit in the cooling operation, and shuts off the refrigerant flow. A refrigerant detection unit is disposed upstream of the outdoor expansion valve and detects the amount or the amount-related value of refrigerant accumulated upstream of the outdoor expansion valve.

Abstract: A refrigerant circuit (20) includes, in order to perform a vapor compression supercritical refrigeration cycle, a compression mechanism (30), an outdoor heat exchanger (21), an expansion mechanism (40), and an indoor heat exchanger (23). The expansion mechanism (40) includes, for the two-stage expansion of refrigerant in the refrigerant circuit (20), a first throttle mechanism (41) variable in the amount of throttling and a second throttle mechanism (42) variable in the amount of throttling. In the cooling operation mode, there is derived a target value for the pressure of high pressure refrigerant in the refrigerant circuit (20), from the temperature of refrigerant at the outlet of the outdoor heat exchanger (21) and the temperature of air at the inlet of the outdoor heat exchanger (21).

Abstract: A transcritical vapor compression system includes a fluid circuit circulating a refrigerant in a closed loop. The fluid circuit has operably disposed therein, in serial order, a first compressor, an intercooler, a second compressor with a variable capacity, a first heat exchanger, an expansion device and a second heat exchanger. The first compressor compresses the refrigerant from a low pressure to an intermediate pressure. The second compressor compresses the refrigerant from the intermediate pressure to a supercritical pressure. The first heat exchanger is positioned in a high pressure side of the fluid circuit. The second heat exchanger is positioned in a low pressure side of the fluid circuit. The expansion device reduces the pressure of the refrigerant from a supercritical pressure to a relatively lower pressure. Cooling means cools the refrigerant within one of the compressors.

Abstract: A refrigerant system control operates tandem compressors. If one of the monitored system conditions does not change as each of the tandem compressors or associated components is brought on line, then a determination is made that the respective component is malfunctioning. A refrigerant system can also be additionally equipped with other functions and components, such as variable speed drive, economizer circuit, unloader bypass, and reheat circuit. In case of a reheat circuit, the system can consist of single or multiple compressors. The control algorithm can also be updated such that that particular malfunctioning component is eliminated from the operational sequence.

Abstract: A refrigeration system (1) includes first to third compressors (11a, 11b, 11c) connected in parallel and an oil separator for separating a refrigeration oil from a refrigerant discharged from the compressors (11a, 11b, 11c). A main suction pipe (55) in which a refrigerant to be sucked into the compressors (11a, 11b, 11c) flows includes a primary curved portion (101) and a primary branch element (102) assembled to part of the main suction pipe (55) downstream of a junction with an oil return pipe (71) for returning the refrigeration oil separated by the oil separator. The main suction pipe (55) is branched by the primary branch element (102) into a first suction pipe branch (61a) of the first compressor (11a) and a connecting suction pipe (56). In the primary branch element (102), the first suction pipe branch (61a) is at the bottommost position and the outermost position in the direction of a radius of curvature of the primary curved portion (101).

Abstract: Disclosed is an apparatus and method for preventing liquid refrigerant accumulation in an accumulator of an outdoor unit of an air conditioner. The method includes the steps of: determining a state of a compressor; if the compressor is in standby mode or off state, turning on a four-way valve; determining whether the state of the compressor in standby mode or off state continues longer than a predetermined amount of time; and if the state of the compressor continues longer than the predetermined amount of time, closing an expansion valve. Particularly, high-pressure refrigerant flows in the closed expansion valve while low-pressure refrigerant flows in a check valve through the four-way valve.

Abstract: The present invention discloses an air conditioning system comprises a phase separator separating a gaseous refrigerant and a liquid refrigerant from a flowing refrigerant, an evaporator evaporating the liquid refrigerant separated by the phase separator, and at least one compressor including a first compressing part receiving the refrigerant via the evaporator and a second compressing part receiving both of the gaseous refrigerant separated by the phase separator and the refrigerant via the first compressing part, wherein a volume of a first cylinder of the first compressing part is different from a volume of a second cylinder of the second compressing part.

Abstract: A coaxial economizer for use in a chiller system comprising an inner housing and an outer housing having a common longitudinal axis. The outer housing has an inlet for receiving a fluid from a upstream compressor stage of a multistage compressor and an outlet for conveying a fluid to a downstream compressor stage of a multistage compressor. A flow chamber forms a fluid flow path about the inner housing. A flash chamber is coterminous with the flow chamber and flashes fluid in a liquid state to a gas state. A flow passage between said flash chamber and the flow chamber for conveying a flashed gas from the flash chamber to the flow chamber; wherein the flashed gas conveyed from the flash chamber and the fluid received from the inlet of the outer housing mix along the fluid flow path toward the outlet of the outer housing.

Abstract: A centrifugal compressor assembly for compressing refrigerant in a 250-ton capacity or larger chiller system comprising a motor, preferably a compact, high energy density motor or permanent magnet motor, for driving a shaft at a range of sustained operating speeds under the control of a variable speed drive. Another embodiment of the centrifugal compressor assembly comprises a mixed flow impeller and a vaneless diffuser sized such that a final stage compressor operates with an optimal specific speed range for targeted combinations of head and capacity, while a non-final stage compressor operates above the optimum specific speed of the final stage compressor.

Abstract: A turbo compressor includes an impeller which is rotationally driven, and a flow path in which the impeller is provided, and through which gas flows, the turbo compressor sucking and compressing the gas in the flow path. The turbo compressor further includes a fluid discharge device which discharges a liquid in the flow path on the upstream side of the impeller.

Abstract: A refrigerant stream is passed through at least one heat exchanger to provide a first at least partially evaporated stream and a second at least partially evaporated stream. A first compressor feed stream is provided from the first partially evaporated stream, and a second compressor feed stream is provided from the second partially evaporated stream. The first compressor feed stream is passed through a first refrigerant compressor and the second compressor feed stream through a second compressor, to provide first and second compressed streams, which are combined at a common pressure. The first refrigerant compressor is controlled by heating the second at least partially evaporated stream or the second compressor feed stream, or vice versa.

Abstract: An HVAC system and method for configuring a controller to control a compressor including a detection system provided to determine a type of compressor. The detection system includes a processor; and a load sensing circuit connected between the processor and a controller. The controller has a plurality of output connections connectable to a compressor. The load sensing circuit senses whether a load is present on each output connection of the plurality of output connections and provides a load signal to the processor indicating whether a load is present on each output connection. The load signals are processed with the processor to determine the type of compressor is present. The controller is configured to control the compressor in response to the determined type of compressor.

Abstract: A multi-stage compressor unit for a refrigeration system configured to circulate a refrigerant comprises a first compressor sub-unit having a first stage and a second stage, and a second compressor sub-unit in parallel with the first compressor sub-unit and having a first stage. The first and second stages of the first compressor sub-unit each have a suction port and a discharge port. The first compressor sub-unit is configured to receive and compress a first portion of the refrigerant from an evaporator. The first stage of the second compressor sub-unit is configured to compress a second portion of the refrigerant.

Abstract: The present invention includes the equipment and processes necessary to convert packaged air-cooled rooftop HVAC units so that they may be served off of a centralized, water-cooled, refrigeration system thereby increasing the energy efficiency and reliability of the HVAC units, and potentially reduce maintenance costs for facilities with multiple packaged air-cooled rooftop HVAC units.

Abstract: A method for controlling multiple compressors for use in an airconditioner is disclosed. In the airconditioner having N compressors, the method sequentially and equally operates the N compressors using a two-dimensional matrix which prevents only a specific compressor from among the N compressors from being repeatedly operated, arranges rows and columns of the two-dimensional matrix to allow all compressors to be alternately operated according to the number of operating compressors from among all compressors, and stochastically operates and stops the N compressors using the two-dimensional matrix. As a result, the method controls the N compressors to be equally operated without overlapping operation times of the N compressors, and alleviates fatigue of the compressors, resulting in equally longer lifetimes of the N compressors.

Abstract: In a refrigeration system having a refrigerant circuit (20) that is constructed in such a way that a plurality of lines of refrigeration circuits (70, 80) having refrigeration heat exchangers (72, 84) respectively are connected to an outdoor circuit (30) provided with an outdoor heat exchanger (32) and a compression mechanism (31) and conducts a vapor compression type refrigeration cycle, at least one of the lines of refrigeration circuits (80) having an auxiliary compressor (85) connected in series to the refrigeration heat exchanger (84), in order to respond to a variety of patterns of defrosting operations without providing a defrosting mechanism other than the refrigerant circuit (20), there is provided a hot gas introduction passage (46, 89) for selectively introducing gas refrigerant discharged from the compression mechanism (31) of the outdoor circuit (30) into at least one of the plurality of refrigeration heat exchangers (72, 84) and a defrosting operation of conducting a refrigeration cycle by using

Abstract: A refrigeration device containing CO2 a refrigerant to be circulated, comprising: a compressor (1, 10, 11), a heat-rejecting heat exchanger (3, 30), an expansion device (7a, 7b, 70a, 70b, 71), and an evaporator (8a, 8b, 80a, 80b, 81) which are connected to one another, wherein the refrigeration device comprises a first portion (61, 71, 81, 11, 92, 10) and a second portion (60, 70a, 80a, 90, 10), the second portion having a higher temperature relative to the first portion when the refrigeration device is in operation; and a heat-reclaim heat exchanger (E1, E2, E3, E4) provided at a given location in the second portion, provided to transfer heat to a fluid for further use as a source of heated fluid.

Abstract: Disclosed is an air conditioner which includes a plurality of compressors, a common inlet pipe through which fluid flows to the compressors, a plurality of inlet pipes branching off from the common inlet pipe which are connected to the compressors, a plurality of outlet pipes connected to the compressors through which refrigerant discharged from the compressors passes, and a plurality of bypass pipes connected to the compressors through which fluid discharged from the compressors passes. The fluid which passes through the plurality of bypass pipes is distributed to the plurality of compressors through the common inlet pipe.

Abstract: A refrigerant circuit (10) includes a gas-liquid separator (15) and a compressor (30) including a low pressure side compression mechanism (34) and a high pressure side compression mechanism (35) connected to each other by means of a drive shaft (33). In the refrigerant circuit (10), a two-stage compression/two-stage expansion refrigeration cycle is performed with CO2 refrigerant utilized as that at its critical pressure. In the compressor (30), a volume ratio V2/V1 of the displacement volume V2 of the second compression mechanism (35) to that V1 of the first compression mechanism is set within a range between 0.8 and 1.3, both exclusive.

Abstract: A refrigerant circuit (20) includes a low stage compressor (101, 102, 121, 122), a high stage compressor (41, 42, 43), an outdoor heat exchanger (44) and a utilization side heat exchanger (83, 93). During a defrosting operation of the refrigeration system (10), the high stage compressor (41, 42, 43) is driven. Refrigerant discharged from the high stage compressor (41, 42, 43) is pumped into the utilization side heat exchanger (83, 93) to heat frost on it from its inside. Thereafter, the refrigerant evaporates in the outdoor heat exchanger (44), is then compressed by the high stage compressor (41, 42, 43) and is sent again to the utilization side heat exchanger (83, 93).

Abstract: A refrigeration system includes a two-stage linear compressor having a first piston disposed in a first cylinder and a second piston disposed in a second cylinder. The linear compressor is operable in an economizer cycle wherein the first piston operates as a first stage of the economizer cycle and the second piston operates as a second stage of the economizer cycle. A controller is coupled to the linear compressor to control a volume flow ratio of the linear compressor. The controller stores a plurality of coefficients of performance for a range of particular operating conditions of the linear compressor and each coefficient of performance corresponds to a desired volume flow ratio and a desired secondary evaporating temperature.

Abstract: A compressor (20) is provided with compression mechanisms (61, 62) to have four compression chambers (61, 62, 63, 64) in total. In the compressor (20), the first compression chamber (61) and the second compression chamber (62) differ in the phase of capacity changing cycle from each other by 180° and the third compression chamber (63) and the fourth compression chamber (64) also differ in the phase of capacity changing cycle from each other by 180°. In a cylinder nonoperating mode, refrigerant is compressed in a single stage in each of the first compression chamber (61) and the second compression chamber (62) while the refrigerant compression operation is halted in the third compression chamber (63) and the fourth compression chamber (64). In a two-stage compression mode, refrigerant compressed in a single stage in each of the first compression chamber (61) and the second compression chamber (62) is further compressed in the third compression chamber (63) and the fourth compression chamber (64).

Abstract: The invention provides a refrigerator having a two-stage compression compressor capable of performing efficient cooling of a both a refrigerator compartment and a freezer compartment. A high-pressure delivery outlet of a two-stage compression compressor 12 is connected to a condenser 14, the condenser 14 is connected to a three-way valve 15, a first outlet of the three-way valve 15 is connected via an R capillary tube 16 and an R evaporator 18 to an intermediate-pressure intake of the two-stage compression compressor 12, is connected and via an F capillary tube 24 to an F evaporator 26, the F evaporator is connected to a low-pressure intake of the two-stage compression compressor 12 via a low-pressure suction pipe 28, the three-way valve 15 can switch between a simultaneous cooling mode and a freezer mode, and when in the simultaneous cooling mode the interior temperature of the refrigerator compartment 2 falls to a predetermined temperature it switches to the freezer mode.

Abstract: A refrigeration apparatus (1) is provided with a refrigerant circuit (1E) along which are connected a compressor (2), an outdoor heat exchanger (4), an expansion mechanism, an indoor heat exchanger (41) for providing room air conditioning, and a cooling heat exchanger (45, 51) for providing storage compartment cooling. The refrigerant circuit (1E) includes a discharge side three way switch valve (101) for varying the flow rate of a portion of the refrigerant which is discharged out of the compressor (2) and then distributed to the indoor heat exchanger (41) and the outdoor heat exchanger (4) during a heat recovery operation mode in which the indoor heat exchanger (41) and the outdoor heat exchanger (4) operate as condensers. As a result of such arrangement, even when the amount of heat obtained in the cooling heat exchanger (45, 51) exceeds the amount of heat required in the indoor heat exchanger (41), surplus heat is discharged without excessive decrease in the discharge pressure of the compressor (2).

Abstract: A tandem compressor system is utilized that receives refrigerant from a common suction manifold, and from a common evaporator. From the compressors, the refrigerant passes to a plurality of condensers, with each of the condensers being associated with a separate zone for heat rejection, preferably at different temperature levels. Each of the condensers is associated with at least one of the plurality of compressors. A reheat coil is associated with the evaporator to improve comfort level in the environment to be conditioned. Multiple reheat circuits associated with separate condensers are employed to provide various stages of reheat or to condition separate environments. By utilizing the common evaporator, a plurality of condensers, and the reheat coils, the ability to independently control temperature, humidity and amount of heat rejection to a number of zones is achieved without the requirement of having dedicated circuits with multiple additional components.

Abstract: Combined medium and low temperature refrigeration circuit for circulating a refrigerant in a predetermined flow direction includes, in flow direction, a heat-rejecting heat exchanger, a medium temperature refrigeration consumer, a medium pressure vapor separator having a vapor portion and a liquid portion connected to the medium temperature refrigeration consumer unit, a low temperature refrigeration consumer connected to the liquid portion of the medium pressure vapor separator, and a compressor unit having an inlet connected to the vapor portion of the medium pressure vapor separators and the low temperature refrigeration consumer.

Abstract: A refrigerant vapor compression system for conditioning air within a climate controlled space has multiple refrigerant circuits including at least one refrigerant circuit having a fixed capacity and at least one refrigerant circuit having a variable capacity. Each refrigerant circuit includes a compressor, a condenser, an expansion device and an evaporator connected in refrigerant circulation flow communication. The compressor associated with each fixed capacity refrigerant circuit is a fixed speed compressor and the compressor associated with each variable capacity refrigerant circuit is a variable speed compressor. A controller is provided for controlling the speed of the variable speed compressor to adjust the refrigeration capacity of the variable capacity refrigerant circuit and thereby adjust the overall capacity of the system to match the cooling demands.

Abstract: A method for energy management of air-conditioning units in motor vehicles in which each of the air-conditioning units has a plurality of air-conditioning compressors prevents very heavy loading of an engine of a motor vehicle and prevents the engine from almost stalling when the air-conditioning compressors start up, as currently occurs during starting of the engine of the motor vehicle, after idling of the engine of the motor vehicle, and after an acceleration process in which the engine was in the full load mode. Each of the air-conditioning compressors is allocated a different priority, with the highest priority, for example, assigned to the air-conditioning compressor for a front vehicle region which is intended, inter alia, to prevent the front windscreen from misting up by removing moisture from the air. A lower priority can be assigned to the air-conditioning compressor for a rear vehicle region.

Abstract: The invention provides a refrigeration system including a plurality of refrigerated display cases. Each display case has a dedicated evaporator assembly that cools return air by evaporating a refrigerant, and a first stage compressor assembly that is in fluid communication with the respective evaporator assembly to compress the refrigerant to a first pressure corresponding to a first temperature of the refrigerant prior to discharge of the compressed refrigerant. The refrigeration system also includes a second stage compressor assembly that is in fluid communication with the first stage compressor assemblies to compress the refrigerant to a second pressure that is higher than the first pressure, and that corresponds to a second temperature of the refrigerant. The refrigeration system further includes a heat exchanger that is in fluid communication with the second stage compressor assembly to receive the refrigerant from the second stage compressor assembly to reject heat from the refrigerant.

Abstract: A refrigerating apparatus, including a turbo compressor including a driving motor and a plurality of bearing members supporting a rotation axis of the driving motor; a condenser provided to condense a refrigerant gas compressed from the turbo compressor; a refrigerant supplying part supplying a part of a refrigerant discharged from an outlet of the condenser to the turbo compressor to cool down the driving motor and the bearing members; and a refrigerant discharging part provided to discharge a cooling refrigerant supplied by the refrigerant supplying part and passing through the turbo compressor. Thus, the refrigerating apparatus cools a driving motor and a bearing member of a turbo compressor without difficulty. Also, the refrigerating apparatus restrains a refrigerant from leaking between an impeller and a diffuser, and increases the efficiency of the turbo compressor.

Abstract: In order to create a refrigeration system comprising a refrigerant circuit (10), in which a main mass flow (56) of a refrigerant is guided, which may be adapted to different operating conditions in an optimum manner it is suggested that at least two refrigerant compressors (12a, 12b, 12c), which can be switched on individually for the purpose of compressing the main mass flow, be arranged in the refrigerant circuit, that at least two of the refrigerant compressors each have at least one additional compressor stage (70), that each of the additional compressor stages be able to be used optionally for the compression of refrigerant from the main mass flow or for the compression of refrigerant from the additional mass flow (86) and that a control (90) be provided, with which such a number of additional compressor stages for the compression of refrigerant from the additional mass flow can be switched on in a first operating mode as a function of the operation conditions that the expansion cooling device (24, 28) l

Abstract: A refrigerant vapor compression system includes a first compression device and a second compression device disposed in a refrigerant circuit in series relationship with respect to refrigerant flow and an intercooler adapted to cool the refrigerant passing from the first compression device to the second compression. An evaporator is provided in the refrigerant circuit wherein the refrigerant accepts heat from a moisture bearing gas such as air. Condensate formed of moisture condensing out of the gas is collected and supplied to the intercooler for cooling the refrigerant flowing from the first compression device to the second compression device.

Abstract: A refrigerant circuit (10) of a refrigeration apparatus is filled up with carbon dioxide as a refrigerant. In the refrigerant circuit (10), a first compressor (21) and a second compressor (22) are arranged in parallel. The first compressor (21) is connected to both an expander (23) and a first electric motor (31), and is driven by both of the expander (23) and the first electric motor (31). On the other hand, the second compressor (22) is connected only to a second electric motor (32), and is driven by the second electric motor (32). In addition, the refrigerant circuit (10) is provided with a bypass line (40) which bypasses the expander (23). The bypass line (40) is provided with a bypass valve (41). And, the capacity of the second compressor (22) and the valve opening of the bypass valve (41) are regulated so that the COP of the refrigeration apparatus is improved after enabling the refrigeration apparatus to operate properly in any operation conditions.

Abstract: A two stage reciprocating compressor includes a casing. A first compressing unit is disposed in the casing and includes a first piston and a first cylinder, the first compressing unit being driven by a reciprocating motor to linearly reciprocate the first piston in the first cylinder to suck in and compress gas. A second compressing unit is disposed in the casing and includes a second piston and a second cylinder, the second compressing unit being driven by vibration of the first compressing unit to linearly reciprocate the second piston in the second cylinder to suck in and compress gas. A vibration transfer member transfers the vibration from the first compressing unit to the second compressing unit. The first and second compressing units extend in parallel and face toward each other.

Abstract: A two stage reciprocating compressor includes a casing. A first compressing unit is disposed in the casing and includes a first piston and a first cylinder, the first compressing unit being driven by a reciprocating motor to linearly reciprocate the first piston in the first cylinder to suck in and compress gas. A second compressing unit is disposed in the casing and includes a second piston and a second cylinder, the second compressing unit being driven by vibration of the first compressing unit to linearly reciprocate the second piston in the second cylinder to suck in and compress gas. A vibration transfer member transfers the vibration from the first compressing unit to the second compressing unit. The first and second compressing units extend in parallel and face in the same direction, the second compressing unit being located adjacent to a suction passage of the first compressing unit.

Abstract: A compression system for an air conditioning system includes first and second compressors. The first compressor includes a first compression chamber in which a fluid introduced from an outside of the first compressor is compressed, and a first case defining a first space into which the fluid compressed in the first compression chamber is introduced. The second compressor includes a second case defining a second space into which the fluid compressed in the first compressor is introduced, and a second compression chamber in which the fluid introduced from the second space is compressed. The second compressor operates independently of the first compressor, and a connecting line connects the first and second compressors.

Abstract: An air conditioner includes a fixed displacement-type first compression mechanism and a variable displacement-type second compression mechanism independent from each other in a refrigeration cycle, and further includes second compression mechanism displacement control means, compression mechanism operation switching control means, an evaporator for refrigerant, a condenser, a blower, evaporator temperature detection means, and evaporator target temperature calculation means. When the refrigeration cycle is operated only by the first compression mechanism, referring to a temperature (Teva) detected by the evaporator temperature detection means, a temperature (Toff) calculated by the evaporator target temperature calculation means and a predetermined value A, if a condition of Teva?Toff?A is satisfied, both compression mechanisms are operated simultaneously.