Cooling device with a suction tube heat exchanger and method for operating a cooling device with a suction tube heat exchanger

Abstract

A refrigeration device has a coolant circuit with a compressor, a first evaporator assembly, and a high-pressure tube connected upstream of the first evaporator assembly. A second evaporator assembly is connected in parallel with the first evaporator assembly. A low-pressure tube is connected downstream of the first and second evaporator assemblies. A suction tube heat exchanger has a high-pressure tube section of the high-pressure tube and a low-pressure tube section of the low-pressure tube heat-conductively coupled. The suction tube heat exchanger has three temperature sensors in three positions from a group of positions at the inlet and outlet of the low-pressure tube section, and at the inlet and outlet of the high-pressure tube section. A ratio of the mass flow of coolant to the first evaporator assembly relative to the total mass flow of the coolant can be determined.

1 - 14 . (canceled) 
     
     
         15 . A refrigeration appliance, comprising:
 a refrigerant circuit with a compressor, a first evaporator assembly having at least one first evaporator, a high-pressure tube connected upstream of said first evaporator assembly, a second evaporator assembly connected in parallel with said first evaporator assembly and having at least one second evaporator, and a low-pressure tube connected downstream of said first evaporator assembly and said second evaporator assembly;   a suction tube heat exchanger, in which a high-pressure tube section of said high-pressure tube and a low-pressure tube section of said low-pressure tube are heat-conductively coupled;   said suction tube heat exchanger having three temperature sensors at three positions selected from a group of positions at an inlet and at an outlet of said low-pressure tube section, and at an inlet and at an outlet of said high-pressure tube section.   
     
     
         16 . The refrigeration appliance according to  claim 15 , wherein said high-pressure tube section leads exclusively to said first evaporator assembly and does not lead to said second evaporator assembly. 
     
     
         17 . The refrigeration appliance according to  claim 15 , which comprises a variably adjustable flow restriction element connected upstream and downstream respectively of said first evaporator and said second evaporator. 
     
     
         18 . The refrigeration appliance according to  claim 17 , wherein said variably adjustable flow restriction element is an expansion valve. 
     
     
         19 . The refrigeration appliance according to  claim 15 , wherein said suction tube heat exchanger has a temperature sensor at each position of the group of positions. 
     
     
         20 . The refrigeration appliance according to  claim 15 , further comprising a facility for determining a ratio of mass flows in said high-pressure tube section and in said low-pressure tube section. 
     
     
         21 . The refrigeration appliance according to  claim 20 , further comprising a facility for determining a ratio of the mass flows to said first evaporator assembly and to said second evaporator assembly. 
     
     
         22 . The refrigeration appliance according to  claim 15 , further comprising a third evaporator between said parallel-connected first and second evaporators and said low-pressure tube. 
     
     
         23 . The refrigeration appliance according to  claim 22 , which comprises a further suction tube heat exchanger, in which a refrigerant tube section at an outlet of said first evaporator and a further tube section of said low-pressure tube are heat-conductively coupled, or said third evaporator having a temperature sensor, which replaces a temperature sensor at the inlet of said low-pressure tube section. 
     
     
         24 . A method of determining a ratio of mass flows in a refrigeration appliance with a refrigerant circuit having a compressor, a first evaporator assembly with at least one first evaporator and with a high-pressure tube connected upstream of the first evaporator assembly, a second evaporator assembly connected in parallel with the first evaporator assembly with at least one second evaporator, a low-pressure tube connected downstream of the first evaporator assembly and the second evaporator assembly, and a suction tube heat exchanger, in which a high-pressure tube section of the high-pressure tube and a low-pressure tube section of the low-pressure tube are heat-conductively coupled, and wherein the suction tube heat exchanger has a group of positions at the inlet and at the outlet of the low-pressure tube section, and at the inlet and at the outlet of the high-pressure tube section;
 the method comprising the following steps:   (a) determining respective temperatures at three positions of the group of positions;   b) determining a ratio of a mass flow through the high-pressure tube section to a mass flow through the low-pressure tube section from the temperatures determined in step a).   
     
     
         25 . The method according to  claim 24 , wherein step a) further comprises:
 a′) determining the temperatures at all positions of the group of positions.   
     
     
         26 . The method according to  claim 24 , wherein the step of determining the ratio of the mass flow through the high-pressure tube section to the mass flow through the low-pressure tube section comprises determining specific thermal capacities of a refrigerant, under an assumption that a refrigerant in the high-pressure tube section is a liquid refrigerant and a refrigerant in the low-pressure tube section is a gaseous refrigerant. 
     
     
         27 . The method according to  claim 24 , which comprises:
 c) determining the mass flow through the low-pressure tube section from a delivery of the compressor.   
     
     
         28 . The method according to  claim 24 , which comprises:
 d) determining a mass flow through the second evaporator assembly from a ratio of the mass flow through the high-pressure tube section to the mass flow through the low-pressure tube section.   
     
     
         29 . The method according to  claim 24 , which further comprises:
 controlling the refrigeration appliance based on the ratio of the mass flow through the high-pressure tube section to the mass flow through the low-pressure tube section.