Ejector cycle system

Abstract

An ejector cycle system with a refrigerant cycle through which refrigerant flows includes an ejector disposed downstream of a radiator, a first evaporator that evaporates refrigerant flowing out of the ejector, a throttling unit located in a branch passage and depressurizes refrigerant to adjust a flow rate of refrigerant, and a second evaporator located downstream of the throttling unit. In the ejector cycle system, a flow ratio adjusting means adjusts a flow ratio between a first refrigerant flow amount depressurized and expanded in a nozzle portion of the ejector and a second refrigerant flow amount drawn into a refrigerant suction port of the ejector, based on a physical quantity related to at least one of a state of refrigerant in the refrigerant cycle, a temperature of a space to be cooled by the first and second evaporators, and an ambient temperature of the space.

1 . An ejector cycle system with a refrigerant cycle through which refrigerant flows, comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat from high-pressure refrigerant discharged from the compressor;    an ejector disposed downstream of the radiator, the ejector having a nozzle portion for depressurizing and expanding refrigerant, a refrigerant suction port through which refrigerant is drawn by a high-speed refrigerant flow jetted from the nozzle portion, and a pressure increasing portion for mixing refrigerant drawn through the refrigerant suction port with the high-speed refrigerant flow and for decelerating the mixed refrigerant flow to raise a pressure of the refrigerant flow;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a branch passage that is branched from a branch portion between the radiator and the ejector and is coupled to the refrigerant suction port, for guiding refrigerant from the radiator into the refrigerant suction port;    a throttling unit that is located in the branch passage and depressurizes refrigerant to adjust a flow rate of refrigerant;    a second evaporator that is located downstream of the throttling unit and evaporates refrigerant; and    a flow ratio adjusting means which adjusts a flow ratio between a first refrigerant flow amount depressurized and expanded in the nozzle portion of the ejector and a second refrigerant flow amount drawn into the refrigerant suction port, based on at least a physical quantity related to at least one of a state of refrigerant in the refrigerant cycle, a temperature of a space to be cooled by the first evaporator and the second evaporator, and an ambient temperature of the space to be cooled.    
   
   
       2 . The ejector cycle system according to  claim 1 , 
 wherein the flow ratio adjusting means is constructed of the ejector itself.    
   
   
       3 . The ejector cycle system according to  claim 1 , 
 wherein the flow ratio adjusting means is constructed of the throttling unit itself.    
   
   
       4 . The ejector cycle system according to  claim 1 , 
 wherein the flow ratio adjusting means is constructed of a variable throttling member that is different from the ejector and the throttling unit.    
   
   
       5 . The ejector cycle system according to  claim 4 . 
 wherein the variable throttling member is located between the branch portion of the branch passage and a refrigerant inflow port of the nozzle portion of the ejector.    
   
   
       6 . The ejector cycle system according to  claim 1 , 
 wherein the throttling unit is a variable throttle member located between the branch portion of the branch passage and a refrigerant inflow port of the second evaporator.    
   
   
       7 . The ejector cycle system according to  claim 4 , 
 wherein the variable throttling member is located at the branch portion of the branch passage.    
   
   
       8 . An ejector cycle system with a refrigerant cycle through which refrigerant flows, comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat from high-pressure refrigerant discharged from the compressor;    an ejector disposed downstream of the radiator, the ejector having a nozzle portion for depressurizing and expanding refrigerant, a refrigerant suction port through which refrigerant is drawn by a high-speed refrigerant flow jetted from the nozzle portion, and a pressure increasing portion for mixing refrigerant drawn through the refrigerant suction port with the high-speed refrigerant flow and for decelerating the mixed refrigerant flow to raise a pressure of the refrigerant flow;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a branch passage that is branched from a branch portion between the radiator and the ejector and is coupled to the refrigerant suction port, for guiding refrigerant from the radiator into the refrigerant suction port;    a throttling unit that is located in the branch passage and depressurizes refrigerant to adjust a flow rate of refrigerant;    a second evaporator that is located downstream of the throttling unit and evaporates refrigerant; and    a flow amount adjusting means which adjusts a flow amount in the whole refrigerant cycle, based on at least a physical quantity related to at least one of a state of refrigerant in the refrigerant cycle, a temperature of a space to be cooled by the first evaporator and the second evaporator, and an ambient temperature of the space to be cooled.    
   
   
       9 . The ejector cycle system according to  claim 8 , 
 wherein the flow amount adjusting means is located upstream of the branch portion of the branch passage.    
   
   
       10 . An ejector cycle system with a refrigerant cycle through which refrigerant flows, comprising: 
 a compressor that draws and compresses refrigerant;    a discharge capacity varying section that adjusts a flow amount of refrigerant discharged from the compressor;    a radiator that radiates heat from high-pressure refrigerant discharged from the compressor;    an ejector disposed downstream of the radiator, the ejector having a nozzle portion for depressurizing and expanding refrigerant, a refrigerant suction port through which refrigerant is drawn by a high-speed refrigerant flow jetted from the nozzle portion, and a pressure increasing portion for mixing refrigerant drawn through the refrigerant suction port with the high-speed refrigerant flow and for decelerating the mixed refrigerant flow to raise a pressure of the refrigerant flow;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a branch passage that is branched from a branch portion between the radiator and the ejector and is coupled to the refrigerant suction port, for guiding refrigerant from the radiator into the refrigerant suction port;    a throttling unit that is located in the branch passage and depressurizes refrigerant to adjust a flow rate of refrigerant; and    a second evaporator that is located downstream of the throttling unit and evaporates refrigerant,    wherein the discharge capacity varying means adjusts the flow amount of refrigerant discharged from the compressor, based on at least a physical quantity related to at least one of a state of refrigerant in the refrigerant cycle, a temperature of a space to be cooled by the first evaporator and the second evaporator, and an ambient temperature of the space to be cooled.    
   
   
       11 . The ejector cycle system according to  claim 10 , 
 wherein the compressor is a displacement variable compressor, and    wherein the discharge capacity varying section is an electrical capacity control valve which adjusts the flow amount of the refrigerant discharged from the compressor by changing a discharge capacity of the compressor.    
   
   
       12 . The ejector cycle system according to  claim 10 , 
 wherein the discharge capacity varying section is an electromagnetic clutch which adjusts the flow amount of the refrigerant discharged from the compressor by changing a ratio between an operation state and a non-operation state of the compressor.    
   
   
       13 . An ejector cycle system with a refrigerant cycle through which refrigerant flows, comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat from high-pressure refrigerant discharged from the compressor;    an ejector disposed downstream of the radiator, the ejector having a nozzle portion for depressurizing and expanding refrigerant, a refrigerant suction port through which refrigerant is drawn by a high-speed refrigerant flow jetted from the nozzle portion, and a pressure increasing portion for mixing refrigerant drawn through the refrigerant suction port with the high-speed refrigerant flow and for decelerating the mixed refrigerant flow to raise a pressure of the refrigerant flow;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a branch passage that is branched from a branch portion between the radiator and the ejector and is coupled to the refrigerant suction port, for guiding refrigerant from the radiator into the refrigerant suction port;    a throttling unit that is located in the branch passage and depressurizes refrigerant to adjust a flow rate of refrigerant;    a second evaporator that is located downstream of the throttling unit and evaporates refrigerant; and    a blower unit disposed to blow air to at least one of the first evaporator and the second evaporator,    wherein the blower unit includes an air blowing adjusting means for adjusting an air blowing amount of the blower unit, and    wherein the air blowing adjusting means adjusts the air amount of the blower unit, based on at least a physical quantity related to at least one of a state of refrigerant in the refrigerant cycle, a temperature of a space to be cooled by the first evaporator and the second evaporator, and an ambient temperature of the space to be cooled.    
   
   
       14 . An ejector cycle system with a refrigerant cycle through which refrigerant flows, comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat from high-pressure refrigerant discharged from the compressor;    an ejector disposed downstream of the radiator, the ejector having a nozzle portion for depressurizing and expanding refrigerant, a refrigerant suction port through which refrigerant is drawn by a high-speed refrigerant flow jetted from the nozzle portion, and a pressure increasing portion for mixing refrigerant drawn through the refrigerant suction port with the high-speed refrigerant flow and for decelerating the mixed refrigerant flow to raise a pressure of the refrigerant flow;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a branch passage that is branched from a branch portion between the radiator and the ejector and is coupled to the refrigerant suction port, for guiding refrigerant from the radiator into the refrigerant suction port;    a throttling unit that is located in the branch passage and depressurizes refrigerant to adjust a flow rate of refrigerant;    a second evaporator that is located downstream of the throttling unit and evaporates refrigerant;    a blower unit disposed to blow air to the radiator; and    an air blowing adjusting means for adjusting an air blowing amount of the blower unit,    wherein the air blowing adjusting means adjusts the air blowing amount of the blower unit, based on at least a physical quantity related to at least one of a state of refrigerant in the refrigerant cycle, a temperature of a space to be cooled by the first evaporator and the second evaporator, and an ambient temperature of the space to be cooled.    
   
   
       15 . The ejector cycle system according to  claim 1 , wherein the physical quantity is related to a superheat degree of refrigerant at a refrigerant outlet side of the first evaporator.  
   
   
       16 . The ejector cycle system according to  claim 1 , wherein the physical quantity is related to a superheat degree of refrigerant at a refrigerant outlet side of the second evaporator.  
   
   
       17 . The ejector cycle system according to  claim 1 , wherein the physical quantity is related to a supercool degree of refrigerant at a refrigerant outlet side of the radiator.  
   
   
       18 . The ejector cycle system according to  claim 1 , 
 wherein the high-pressure refrigerant has a pressure higher than a critical pressure of the refrigerant, and    wherein the physical quantity is related to a temperature and a pressure of refrigerant at a refrigerant outlet side of the radiator.    
   
   
       19 . The ejector cycle system according to  claim 1 , 
 wherein the physical quantity is related to the flow ratio.    
   
   
       20 . The ejector cycle system according to  claim 1 , 
 wherein the physical quantity is related to a flow amount of refrigerant discharged from the compressor.    
   
   
       21 . The ejector cycle system according to  claim 1 , further comprising 
 an accumulator located downstream of the first evaporator to separate refrigerant into gas phase refrigerant and liquid phase refrigerant.    
   
   
       22 . The ejector cycle system according to  claim 8 , further comprising 
 an accumulator located downstream of the first evaporator to separate refrigerant into gas phase refrigerant and liquid phase refrigerant.    
   
   
       23 . The ejector cycle system according to  claim 10 , further comprising 
 an accumulator located downstream of the first evaporator to separate refrigerant into gas phase refrigerant and liquid phase refrigerant.    
   
   
       24 . The ejector cycle system according to  claim 13 , further comprising 
 an accumulator located downstream of the first evaporator to separate refrigerant into gas phase refrigerant and liquid phase refrigerant.    
   
   
       25 . The ejector cycle system according to  claim 14 , further comprising 
 an accumulator located downstream of the first evaporator to separate refrigerant into gas phase refrigerant and liquid phase refrigerant.    
   
   
       26 . An ejector cycle system with a refrigerant cycle through which refrigerant flows, comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat from high-pressure refrigerant discharged from the compressor;    an ejector disposed downstream of the radiator, the ejector having a nozzle portion for depressurizing and expanding refrigerant, a refrigerant suction port through which refrigerant is drawn by a high-speed refrigerant flow jetted from the nozzle portion, and a pressure increasing portion for mixing refrigerant drawn through the refrigerant suction port with the high-speed refrigerant flow and for decelerating the mixed refrigerant flow to raise a pressure of the refrigerant flow;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a branch passage that is branched from a branch portion between the radiator and the ejector and is coupled to the refrigerant suction port, for guiding refrigerant from the radiator into the refrigerant suction port;    a throttling unit that is located in the branch passage and depressurizes refrigerant to adjust a flow rate of refrigerant;    a second evaporator that is located downstream of the throttling unit and evaporates refrigerant;    a determining means for determining whether a rapid cooling is necessary for a space to be cooled by the first evaporator and the second evaporator; and    an adjusting means for adjusting an evaporation temperature of at least one of the first evaporator and the second evaporator,    wherein the adjusting means reduces the evaporation temperature of at least one of the first evaporator and the second evaporator when the determining means determines that the rapid cooling is necessary.    
   
   
       27 . The ejector cycle system according to  claim 26 , further comprising 
 an input means capable of inputting a rapid cooling request by a user,    wherein the determining means determines that the rapid cooling is necessary when the rapid cooling request is input through the input means.    
   
   
       28 . The ejector cycle system according to  claim 26 , 
 wherein the determining means determines a rapid cooling, based on at least a physical quantity related to at least one of a state of refrigerant in the refrigerant cycle, a temperature of a space to be cooled by the first evaporator and the second evaporator, and an ambient temperature of the space to be cooled.    
   
   
       29 . The ejector cycle system according to  claim 26 , further comprising 
 a flow ratio adjusting means which adjusts a flow ratio between a first refrigerant flow amount depressurized and expanded in the nozzle portion of the ejector and a second refrigerant flow amount drawn into the refrigerant suction port,    wherein the flow ratio adjusting means shuts a refrigerant flow depressurized and expanded in the nozzle portion of the ejector so as to reduce the evaporation temperature, when the determining means determines that the rapid cooling is necessary.    
   
   
       30 . The ejector cycle system according to  claim 29 , further comprising 
 a variable throttling member located between the branch portion and the nozzle portion of the ejector,    wherein the flow ratio adjusting means is constructed of the throttling unit itself.    
   
   
       31 . The ejector cycle system according to  claim 29 , 
 wherein the flow ratio adjusting means is constructed of the ejector itself.    
   
   
       32 . The ejector cycle system according to  claim 26 , further comprising 
 a discharge capacity varying section that adjusts a flow amount of refrigerant discharged from the compressor,    wherein the discharge capacity varying section increases the flow amount of refrigerant discharged from the compressor so as to reduce the evaporation temperature when the determining means determines that the rapid cooling is necessary.    
   
   
       33 . The ejector cycle system according to  claim 26 , further comprising: 
 a blower unit for blowing air to at least the second evaporator; and    a blower adjusting unit which adjusts an air blowing amount of the blower unit,    wherein the blower adjusting unit reduces the air blowing amount so as to decrease the evaporation temperature when the determining means determines that the rapid cooling is necessary.    
   
   
       34 . The ejector cycle system according to  claim 26 , further comprising 
 an increasing means which increases a superheat degree of refrigerant at an outlet side of at least one of the first evaporator and the second evaporator,    wherein the increasing means increases the superheat degree so as to decrease the evaporation temperature when the determining means determines that the rapid cooling is necessary.    
   
   
       35 . An ejector cycle system comprising: 
 a compressor for compressing refrigerant;    a condenser for cooling and condensing refrigerant compressed by the compressor;    an ejector provided downstream of the condenser, wherein the ejector has a nozzle portion having a refrigerant inlet port, for decompressing refrigerant from the condenser, a refrigerant suction port through which refrigerant is drawn by refrigerant passing through the nozzle portion of the ejector, and a refrigerant outlet port for discharging refrigerant from the ejector;    an evaporator that is disposed to exchange heat between an external fluid and refrigerant branched and introduced from an upstream side of the ejector, and    has a refrigerant outlet connected to the refrigerant suction port of the ejector;    a detection means that detects a controllable factor for determining a staying state of oil in the evaporator;    a determining means that determines whether oil is staying in the evaporator based on an information from the detection means; and    an oil flow-down means that causes the oil to flow down, when the determining means determines that oil is staying in the evaporator.    
   
   
       36 . The ejector cycle system according to  claim 35 , 
 wherein the oil flow-down means increases a flow rate of refrigerant flowing in the evaporator when the controllable factor is not in a predetermined range.    
   
   
       37 . The ejector cycle system according to  claim 35 , 
 wherein a state of superheated refrigerant gas (SH) on a refrigerant outlet side of the evaporator is used as the controllable factor.    
   
   
       38 . The ejector cycle system according to  claim 35 , 
 wherein a refrigerant temperature difference between refrigerant outlet and inlet of the evaporator or a refrigerant pressure loss between the refrigerant outlet and inlet of the evaporator is used as the controllable factor.    
   
   
       39 . The ejector cycle system according to  claim 35 , 
 wherein a pressure difference between the refrigerant suction port and the refrigerant outlet port of the ejector is used as the controllable factor.    
   
   
       40 . The ejector cycle system according to  claim 35 , further comprising: 
 a flow control device that is provided downstream of the condenser and adjusts the flow rate of refrigerant flowing to the ejector and a flow rate of refrigerant flowing to the evaporator,    wherein the flow control device is provided with a variable expansion valve placed upstream of the refrigerant inlet port of the ejector.    
   
   
       41 . The ejector cycle system according to  claim 40 , 
 wherein the oil flow-down means is provided with a controlling means that makes adjustment so as to reduce an opening of the variable expansion valve or the nozzle portion of the ejector when the controllable factor is not in a predetermined range.    
   
   
       42 . The ejector cycle system according to  claim 35 , 
 wherein the oil flow-down means temporarily stops the compressor when the controllable factor is not in a predetermined range.    
   
   
       43 . The ejector cycle system according to  claim 35 , 
 wherein, when the controllable factor is not in a predetermined range, the oil flow-down means hinders a refrigerant cooling in the condenser or increases a load on the fluid medium that exchanges heat with refrigerant in the condenser.    
   
   
       44 . The ejector cycle system according to  claim 35 , further comprising: 
 an another evaporator connected with the outlet port of the ejector.    
   
   
       45 . The ejector cycle system according to  claim 35 , 
 wherein Freon refrigerant, hydrocarbon refrigerant, or carbon dioxide is used as the refrigerant.    
   
   
       46 . An operation method for an ejector cycle system, comprising: 
 passing refrigerant through an ejector and passing refrigerant through an evaporator by a suction force of the ejector;    detecting a controllable factor for determining a staying of oil in the evaporator during the passing; and    causing oil to flow down from the evaporator when the controllable factor is not in a predetermined range.