Heating, Ventilating and/or Air Conditioning System With Cold Air Storage

Abstract

The invention relates to a heating, ventilating and/or air conditioning system with a main air conditioning loop ( 10 ) for a refrigerant including at least one compressor ( 11 ), a condenser ( 12 ), an expansion device ( 13 ) and an evaporator ( 14 ), a cold storage heat exchanger ( 21 ) suitable for storing cold during operation of the compressor ( 11 ), and a secondary air-conditioning loop ( 20 a ) comprising the cold storage heat exchanger ( 21 ). The secondary air-conditioning loop ( 20 a ) is suitable to cool the evaporator ( 14 ) when the compressor ( 11 ) is out of operation. The secondary air-conditioning loop ( 20 a ) includes a fluid circulation branch disposed in parallel with a main air conditioning loop ( 10 ) common section including at least the evaporator ( 14 ). The fluid circulation branch contains a cold production element ( 21 ) able to cool the refrigerant toward the evaporator. The invention is particularly dedicated to heating, ventilating and/or air conditioning systems in “Stop and Start” cars.

1 . A heating, ventilation and/or air conditioning system, said system comprising:
 a main thermodynamic air conditioning loop ( 10 ;  10 ′) for the circulation of a refrigerant including at least a compressor ( 11 ), a condenser ( 12 ), an expansion device ( 13 ;  13 ′) and an evaporator ( 14 ),   a cold storage heat exchanger ( 21 ,  18 ) capable of storing cold refrigerant when the compressor is operating ( 11 ),   a secondary thermodynamic air conditioning loop ( 20   a;    20 ′ a ) that integrates the cold storage heat exchanger ( 21 ;  18 ), the secondary thermodynamic air conditioning loop ( 20   a;    20 ′ a ) assigned to cool the evaporator ( 14 ) when the compressor ( 11 ) is not operating,   
     characterized by a secondary thermodynamic air conditioning loop ( 20   a;    20 ′ a ) that includes a fluid circulation section set on a common section in parallel with the main thermodynamic air conditioning loop ( 10 ;  10 ′) including at least the evaporator ( 14 ), the fluid circulation section including a cold producing element ( 21 ;  23 ′) that can cool the refrigerant going into the evaporator ( 14 ). 
   
   
       2 . A system according to  claim 1 , in which the cold producing element is constituted by the cold storage heat exchanger ( 21 ). 
   
   
       3 . A system according to  claim 2 , in which the fluid circulation section includes a refrigerant circulating pump ( 25 ). 
   
   
       4 . A system according to either  claim 2 , in which the secondary thermodynamic air conditioning loop ( 20   a ) includes a switching device ( 22 ) with at least a first position in which the switching device ( 22 ) allows the refrigerant to flow through an expander ( 23 ) located upstream from the cold storage heat exchanger ( 21 ) and stops the flow of the refrigerant into a bypass section of the expander ( 23 ), and a second position in which the switching device ( 22 ) stops the flow of the refrigerant through the expander ( 23 ) and allows the refrigerant to flow into the bypass section of the expander ( 23 ). 
   
   
       5 . A system according to  claim 4 , in which the switching device is a three way valve ( 22 ). 
   
   
       6 . A system according to  claim 2 , in which the expansion device of the main air conditioning loop is an ejector ( 13 ). 
   
   
       7 . A system according to  claim 6 , in which the fluid circulation section is connected to a low pressure inlet of the ejector ( 13 ). 
   
   
       8 . A system according to  claim 1 , in which the cold producing element is constituted of a secondary expander ( 23 ′). 
   
   
       9 . A system according to  claim 8 , in which the secondary thermodynamic air conditioning loop ( 20 ′ a ) includes a secondary compressor ( 17 ). 
   
   
       10 . A system according to  claim 8 , in which the secondary thermodynamic air conditioning loop ( 20 ′ a ) involves a switching device ( 16 ) with at least a first position in which the switching device ( 16 ) allows the refrigerant to flow through the secondary compressor ( 17 ) located upstream from the cold storage heat exchanger ( 18 ) and stops the flow of the refrigerant into a bypass section of the secondary compressor ( 17 ), and a second position in which the switching device ( 16 ) stops the flow of the refrigerant through the secondary compressor ( 17 ) and allows the refrigerant to flow into the bypass section of the secondary compressor ( 17 ). 
   
   
       11 . A system according to  claim 10 , in which the switching device is a three way valve ( 16 ). 
   
   
       12 . A system according to  claim 1 , in which the secondary thermodynamic air conditioning loop ( 20   a,    20 ′ a ) involves a control device ( 24 ,  27 ) with a first position in which the control device ( 24 ,  27 ) allows cold storage in the cold storage heat exchanger ( 21 ,  18 ) and a second position in which the control device ( 24 ,  27 ) allows the recovery of the cold stored in the cold storage heat exchanger ( 21 ,  18 ). 
   
   
       13 . A system according to  claim 12 , in which the control device is a three way valve ( 24 ,  27 ). 
   
   
       14 . A system according to either  claim 3 , in which the secondary thermodynamic air conditioning loop ( 20   a ) includes a switching device ( 22 ) with at least a first position in which the switching device ( 22 ) allows the refrigerant to flow through an expander ( 23 ) located upstream from the cold storage heat exchanger ( 21 ) and stops the flow of the refrigerant into a bypass section of the expander ( 23 ), and a second position in which the switching device ( 22 ) stops the flow of the refrigerant through the expander ( 23 ) and allows the refrigerant to flow into the bypass section of the expander ( 23 ). 
   
   
       15 . A system according to  claim 9 , in which the secondary thermodynamic air conditioning loop ( 20   a ) involves a switching device ( 16 ) with at least a first position in which the switching device ( 16 ) allows the refrigerant to flow through the secondary compressor ( 17 ) located upstream from the cold storage heat exchanger ( 18 ) and stops the flow of the refrigerant into a bypass section of the secondary compressor ( 17 ), and a second position in which the switching device ( 16 ) stops the flow of the refrigerant through the secondary compressor ( 17 ) and allows the refrigerant to flow into the bypass section of the secondary compressor ( 17 ).