Ejector cycle device

Abstract

In an ejector cycle device having an ejector, an evaporator is arranged in a refrigerant branch passage connected to a refrigerant suction port of the ejector, an opening/closing member for opening and closing a refrigerant passage is disposed to prevent refrigerant from flowing into the evaporator, and a control unit intermittently controls operation of the compressor. In the ejector cycle device, the control unit brings the opening/closing member into a closing state in a time period for which the operation of the compressor is stopped. Accordingly, it can restrict liquid refrigerant from collecting in the evaporator while the compressor is stopped.

1 . An ejector cycle device comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat of high-pressure refrigerant discharged from the compressor;    an ejector disposed at a downstream side of the radiator to decompress and expand refrigerant from the radiator, wherein the ejector has a refrigerant suction port for drawing refrigerant by a high-speed refrigerant flow when refrigerant is expanded, mixes the refrigerant drawn from the refrigerant suction port with the high-speed refrigerant flow and decelerates the mixed refrigerant flow to thereby increase pressure of the mixed refrigerant flow;    an evaporator that is arranged in a refrigerant branch passage connected to the refrigerant suction port;    an opening/closing member that opens and closes a refrigerant flow and is capable of preventing refrigerant from flowing into the evaporator; and    a control unit that brings the opening/closing member into a closing state in a time period for which the operation of the compressor is stopped.    
   
   
       2 . The ejector cycle device according to  claim 1 , wherein the evaporator connected to the refrigerant suction port is arranged as a first evaporator, the ejector cycle device further comprising 
 a second evaporator arranged on a downstream side of the ejector.    
   
   
       3 . The ejector cycle device according to  claim 2 , wherein the first evaporator and the second evaporator are disposed to cool one space to be cooled.  
   
   
       4 . The ejector cycle device according to  claim 2 , wherein the first evaporator and the second evaporator are disposed to cool separate spaces to be cooled.  
   
   
       5 . The ejector cycle device according to  claim 1 , further comprising 
 a temperature detecting member for detecting temperature relating to a temperature of a space to be cooled of the evaporator,    wherein the control unit intermittently controls operation of the compressor on the basis of temperature detected by the temperature detecting member.    
   
   
       6 . The ejector cycle device according to  claim 1 , wherein the refrigerant branch passage is branched at a branch point on an upstream side of the ejector and is connected to the refrigerant suction port.  
   
   
       7 . The ejector cycle device according to  claim 6 , wherein the opening/closing member is an opening/closing valve arranged on an upstream side of the branch point.  
   
   
       8 . The ejector cycle device according to  claim 6 , wherein the opening/closing member is a three-way valve arranged at the branch point.  
   
   
       9 . The ejector cycle device according to  claim 1 , wherein the opening/closing member is an opening/closing valve arranged on an upstream side of the evaporator in the refrigerant branch passage.  
   
   
       10 . The ejector cycle device according to  claim 1 , wherein the opening/closing member is a passage opening/closing mechanism arranged in the ejector itself.  
   
   
       11 . The ejector cycle device according to  claim 1 , wherein the control unit controls the opening/closing member from the closing state to an opening state in the time period for which the compressor is stopped, and then restarts the operation of the compressor.  
   
   
       12 . The ejector cycle device according to  claim 1 , wherein: 
 the opening/closing member includes an opening/closing valve arranged on an upstream side of the evaporator connected to the refrigerant suction port, and a passage opening/closing mechanism arranged in the ejector itself; and    the control unit controls the opening/closing valve from a closing state to an opening state in the time period for which the compressor is stopped to thereby bring pressure in a refrigerant cycle into balance, and then returns the passage opening/closing mechanism into an opening state and then restarts the operation of the compressor.    
   
   
       13 . The ejector cycle device according to  claim 1 , wherein the control unit controls the opening/closing member from an opening state to a closing state before stopping the compressor and continuously keeps the compressor in an operating state for a specified time in a state where the opening/closing member is closed, and then stops the compressor.  
   
   
       14 . The ejector cycle device according to  claim 1 , further comprising 
 a throttle mechanism that is arranged on an upstream side of the opening/closing member, and reduces pressure of refrigerant on the upstream side of the opening/closing member in such a way as to bring the refrigerant into two phases of vapor and liquid.    
   
   
       15 . The ejector cycle device according to  claim 1 , wherein the ejector and the opening/closing valve are combined with each other at least as one integrated unit.  
   
   
       16 . An ejector cycle device comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat of high-pressure refrigerant discharged from the compressor;    an ejector that includes a nozzle portion for reducing pressure of refrigerant on a downstream side of the radiator to expand the refrigerant, and draws refrigerant by a jet flow of refrigerant from the nozzle portion;    a first evaporator that evaporates refrigerant to be drawn into a refrigerant suction port of the ejector, so as to have a cooling capacity;    a second evaporator that evaporates refrigerant flowing out of the ejector, so as to have a cooling capacity;    a frost removing member that heats the first and second evaporators so as to perform a frost removing operation where frost adhering to the first and second evaporators is removed;    an evaporator temperature detecting member that detects temperature of at least one of the first evaporator and the second evaporator; and    a control unit that controls the frost removing member to heat the first and second evaporators and to perform the frost removing operation when temperature detected by the evaporator temperature detecting member reaches a predetermined temperature.    
   
   
       17 . The ejector cycle device according to  claim 16 , wherein: 
 the evaporator temperature detecting member is disposed to detect the temperature of the first evaporator; and    the control unit controls the frost removing member to perform the frost removing operation when temperature of the first evaporator detected by the evaporator temperature detecting member reaches a predetermined temperature.    
   
   
       18 . The ejector cycle device according to  claim 16 , wherein: 
 the evaporator temperature detecting member is disposed to detect the temperature of the second evaporator; and    the control unit controls the frost removing member to perform the frost removing operation when temperature of the second evaporator detected by the evaporator temperature detecting member reaches a predetermined temperature.    
   
   
       19 . The ejector cycle device according to  claim 16 , further comprising: 
 an accumulator that is arranged on a downstream side of the second evaporator in a refrigerant flow; and    an accumulator temperature detecting member that detects a temperature of the accumulator, wherein:    the evaporator temperature detecting member includes a first evaporator temperature sensor disposed to detect a temperature of the first evaporator, and a second evaporator temperature sensor disposed to detect the temperature of the second evaporator; and    the control unit controls the frost removing member to perform the frost removing operation when a temperature detected by any one of the accumulator temperature detecting member and the first and second evaporator temperature sensors reaches a predetermined temperature or more.    
   
   
       20 . The ejector cycle device according to  claim 16 , wherein the frost removing member is arranged on an upstream air side of the first and second evaporators.  
   
   
       21 . The ejector cycle device according to  claim 16 , wherein the frost removing member has an electric heater.  
   
   
       22 . The ejector cycle device according to  claim 21 , wherein the control unit performs the frost removing operation of the first and second evaporators in a state where the compressor is stopped.  
   
   
       23 . The ejector cycle device according to  claim 16 , wherein: 
 the frost removing member has a passage switching means arranged on a downstream side of refrigerant flow of the radiator, and a hot-gas supply passage through which high-temperature refrigerant from the passage switching means is supplied to an upstream side of the refrigerant flow of the second evaporator; and    the control unit controls the passage switching means to switch a refrigerant passage to the hot-gas supply passage in a state where the compressor is operated, and performs the frost removing operation of the first and second evaporators by using the high-temperature refrigerant.    
   
   
       24 . The ejector cycle device according to  claim 16 , wherein the control unit varies the predetermined temperature according to an outside air temperature.  
   
   
       25 . An ejector cycle device comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat of high-pressure refrigerant discharged from the compressor;    an ejector that includes a nozzle portion for reducing pressure of refrigerant on a downstream side of the radiator to expand the refrigerant, and draws refrigerant by a jet flow of refrigerant from the nozzle portion;    a first evaporator that evaporates refrigerant to be drawn into a refrigerant suction port of the ejector, to have a cooling capacity;    a second evaporator that evaporates refrigerant flowing out of the ejector, to have a cooling capacity;    an accumulator that is arranged on a downstream side of the second evaporator in a refrigerant flow;    a frost removing member that heats the first and second evaporators so as to perform a frost removing operation where frost adhering to the first and second evaporators is removed;    an accumulator temperature detecting member that detects a temperature of the accumulator; and    a control unit that controls the frost removing member to heat the first and second evaporators and to perform the frost removing operation when temperature of an outer wall of the accumulator detected by the accumulator temperature detecting member reaches a predetermined temperature.    
   
   
       26 . The ejector cycle device according to  claim 25 , wherein the frost removing member is arranged on an upstream air side of the first and second evaporators.  
   
   
       27 . The ejector cycle device according to  claim 25 , wherein the frost removing member has an electric heater.  
   
   
       28 . The ejector cycle device according to  claim 27 , wherein the control unit performs the frost removing operation of the first and second evaporators in a state where the compressor is stopped.  
   
   
       29 . The ejector cycle device according to  claim 25 , wherein: 
 the frost removing member has a passage switching means arranged on a downstream side of refrigerant flow of the radiator, and a hot-gas supply passage through which high-temperature refrigerant from the passage switching means is supplied to an upstream side of the refrigerant flow of the second evaporator; and    the control unit controls the passage switching means to switch a refrigerant passage to the hot-gas supply passage in a state where the compressor is operated, and performs the frost removing operation of the first and second evaporators by using the high-temperature refrigerant.    
   
   
       30 . The ejector cycle device according to  claim 25 , wherein the control unit varies the predetermined temperature according to an outside air temperature.  
   
   
       31 . The ejector cycle device according to  claim 16 , wherein: 
 the frost removing member is constructed with a plurality of heating portions; and    the control unit controls the first and second evaporators to perform the frost removing operation of the first and second evaporators.    
   
   
       32 . The ejector cycle device according to  claim 16 , wherein the frost removing member contacts both the first and second evaporators to heat the first and second evaporators in the frost removing operation.  
   
   
       33 . The ejector cycle device according to  claim 16 , wherein the frost removing member is disposed to heat both the first and second evaporators in the frost removing operation.  
   
   
       34 . An ejector cycle device comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat of high-pressure refrigerant discharged from the compressor; and    an ejector that includes a nozzle portion for reducing pressure of refrigerant on a downstream side of the radiator to expand the refrigerant, and draws refrigerant by a jet flow of refrigerant from the nozzle portion;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a refrigerant branch passage that is branched from a refrigerant cycle including the compressor, the radiator, the ejector, and the first evaporator, and introduces refrigerant into a refrigerant suction port of the ejector;    a second evaporator that is arranged in the refrigerant branch passage and evaporates refrigerant;    a frost removing member that is disposed to heat the first and second evaporators so as to perform a frost removing operation where frost adhering to the first and second evaporators is removed; and    a control unit that controls the frost removing member to perform the frost removing operation of the first and second evaporators.    
   
   
       35 . The ejector cycle device according to  claim 34 , wherein the frost removing member is constructed with a plurality of heater portions for heating the first and second evaporators in the frost removing operation.  
   
   
       36 . The ejector cycle device according to  claim 34 , wherein the frost removing member is located at an upstream air side of each of first and second evaporators.  
   
   
       37 . The ejector cycle device according to  claim 34 , wherein the frost removing member is located to contact both the first and second evaporators.  
   
   
       38 . The ejector cycle device according to  claim 34 , wherein the frost removing member is located to heat both the first and second evaporators.  
   
   
       39 . The ejector cycle device according to  claim 34 , wherein the frost removing member is provided at one side of the first and second evaporators, further comprising 
 a radiant heat absorbing member provided at the other one of the first and second evaporators such that radiant heat from the frost removing member is delivered to the radiant heat absorbing member.    
   
   
       40 . The ejector cycle device according to  claim 34 , wherein: 
 the frost removing member is provided at one side of the first and second evaporators such that heat from the frost removing member is delivered to the other one of the first and second evaporators by convection.    
   
   
       41 . The ejector cycle device according to  claim 40 , further comprising an air blowing unit which is located to perform the convection.  
   
   
       42 . The ejector cycle device according to  claim 40 , wherein the first and second evaporators are arranged in a vertical direction, and the frost removing member is arranged at a lower position of the first and second evaporators to perform a natural convection in the frost removing operation.  
   
   
       43 . The ejector cycle device according to  claim 34 , wherein the frost removing member has an electric heater.  
   
   
       44 . The ejector cycle device according to  claim 34 , wherein the control unit performs the frost removing operation of the first and second evaporators by the frost removing member in a state where the compressor is stopped.  
   
   
       45 . The ejector cycle device according to  claim 34 , wherein the refrigerant is a flammable refrigerant.  
   
   
       46 . The ejector cycle device according to  claim 16 , further comprising 
 a heat conductive member that connects the first evaporator and the second evaporator to transfer heat between the first evaporator and the second evaporator.    
   
   
       47 . An ejector cycle device comprising: 
 a compressor that draws and compresses refrigerant;    a radiator that radiates heat of high-pressure refrigerant discharged from the compressor;    an ejector that includes a nozzle portion for reducing pressure of refrigerant on a downstream side of the radiator to expand the refrigerant, and draws refrigerant by a jet flow of refrigerant from the nozzle portion;    a first evaporator that evaporates refrigerant flowing out of the ejector;    a refrigerant branch passage that is branched from a refrigerant cycle including the compressor, the radiator, the ejector, and the first evaporator and introduces refrigerant into a refrigerant suction port of the ejector;    a second evaporator that is arranged in the refrigerant branch passage and evaporates refrigerant;    a heat conductive member that connects the first evaporator and the second evaporator to transfer heat between the first evaporator and the second evaporator; and    a frost removing member that is disposed to heat the first and second evaporators to remove frost adhering to the first and second evaporators.    
   
   
       48 . The ejector cycle device according to  claim 47 , wherein the heat conductive member is disposed to contact the frost removing member.  
   
   
       49 . The ejector cycle device according to  claim 47 , further comprising 
 a control unit for controlling a frost removing operation of the first and second evaporators, wherein an amount of heat conduction of the heat conductive member is set in such a way that a refrigerating capacity required by the first and second evaporators is compatible with a frost removing capacity required in the frost removing operation of the first and second evaporators.    
   
   
       50 . The ejector cycle device according to  claim 47 , wherein the heat conductive member includes heat exchange fins disposed in the first and second evaporators.  
   
   
       51 . The ejector cycle device according to  claim 47 , wherein the heat conductive member is a holding member for holding the first and second evaporators.  
   
   
       52 . The ejector cycle device according to  claim 47 , wherein the heat conductive member includes side plates attached to side ends of the first and second evaporators.  
   
   
       53 . The ejector cycle device according to  claim 47 , wherein the heat conductive member is located in the first and second evaporators.