Cooling Storage Cabinet and Method of Operating Thereof

Abstract

When an internal temperature of a freezing compartment becomes lower than a lower limit temperature T F(OFF) during R-compartment F-compartment alternate cooling, a request for start of R-individual overcool preventing control is made. Then, the rotational speed of the compressor is decreased by one stage and, subsequently, a three-way valve comes to a “R-side open state”, and thus individual cooling of the refrigerating compartment is executed. Thereafter, after a set time, the rotational speed of the compressor is decreased by one stages. When the refrigerating compartment becomes lower than a lower limit temperature T R(OFF) , a request for stop of the R-individual overcool preventing control is made. Then, the process shifts to individual cooling of the freezing compartment and then, after waiting for the freezing compartment to again become lower than the lower limit temperature, the compressor is stopped. When shifted to the individual cooling of the refrigerating compartment, the rotational speed of the compressor is drastically decreased in a short time, i.e. the cooling capacity is drastically decreased.

1 - 5 . (canceled) 
   
   
       6 . A method of operating a cooling storage cabinet, the method comprising:
 providing an inverter compressor, a condenser, a valve unit, a first and a second evaporator, constriction units configured to constrict refrigerant flowing into each of the evaporators, and a first and a second storage compartments, the first and the second storage compartments having set temperatures differing from each other, the first and the second storage compartments having the first and the second evaporators;   supplying the refrigerant by the valve unit alternately to the evaporators, while changing a rotational speed of the inverter compressor based on deviations between the set temperatures of each storage compartment and internal temperatures of the same storage compartments, thereby alternately cooling each storage compartment each so that the each compartment becomes closer to the set temperature;   performing individual cooling of only the other storage compartment when the internal temperature of either one of the first and the second storage compartment is lower than the set temperature, and stopping the inverter compressor when the internal temperatures of both of the storage compartments are lower than the respective set temperatures; and   alternately cooling the first and the second storage compartments with operation of the inverter compressor and, thereafter, switching to the individual cooling of the storage compartment having a higher set temperature, decreasing the rotational speed of the inverter compressor.   
   
   
       7 . A cooling storage cabinet, comprising:
 a freezing cycle, including
 an inverter compressor configured to have a changeable rotational speed, 
 a condenser configured to dissipate heat from refrigerant compressed by the inverter compressor, 
 a valve unit having an inlet and two outlets, the inlet being connected to the condenser side, the two outlets being connected to a first and a second refrigerant supply paths, the valve unit being configured to switch a flow path between the inlet side and selectively with at least one of the first and the second refrigerant supply paths, 
 a first and a second evaporator, each of the first and the second evaporator being configured to be provided in respective one of the first and the second refrigerant supply paths, 
 constriction units, each of the constriction units being configured to constrict refrigerant flowing into one of the evaporators, and 
 a refrigerant circulation path configured to provide a common connection between refrigerant outlet sides of the first and the second evaporators, the refrigerant circulation path being configured to be connected to an refrigerant inlet side of the inverter compressor; 
   a storage cabinet body having a first and a second storage compartments, the first and the second storage compartments being configured to have set temperatures differing from each other and to be cooled by cold air generated by the first and the second evaporators;   a first and a second temperature sensors, each of the first and the second temperature sensors being configured to detect internal temperature of respective one of the first and the second storage compartments; and   an operation control means for, during operation of the inverter compressor, supplying the refrigerant by the valve unit alternately to the evaporators, while changing a rotational speed of the inverter compressor based on deviations between the set temperatures of the storage compartments each and internal temperatures of the same storage compartments, thereby alternately cooling the storage compartments each so that the each of the compartments becomes closer to the set temperature,   in a case where the internal temperature of either one of the first and the second storage compartments is lower than the set temperature of the storage compartment, performing individual cooling of only the other storage compartment, and in a case where the internal temperatures of both of the storage compartments are lower than the respective set temperatures, stopping the inverter compressor; and   a compressor control means for, in a case of alternately cooling the first and the second storage compartments accompanying with operation of the inverter compressor and, thereafter, switching to the individual cooling of one of the storage compartments having a higher set temperature, decreasing the rotational speed of the inverter compressor.   
   
   
       8 . The cooling storage cabinet according to  claim 7 , wherein the compressor control means includes a function to decrease the rotational speed of the inverter compressor stage by stage at predetermined time intervals. 
   
   
       9 . The cooling storage cabinet according to  claim 8 , wherein the compressor control means includes a function to decelerate the inverter compressor to a speed not lower than a predetermined minimum rotational speed. 
   
   
       10 . The cooling storage cabinet according to  claim 8 , comprising a control stop means for, in a case where a processing instruction to accelerate the inverter compressor is made during the individual cooling of one of the storage compartments having the higher set temperature, stopping the deceleration function of the inverter compressor. 
   
   
       11 . The cooling storage cabinet according to  claim 9 , comprising a control stop means for, in a case where a processing instruction to accelerate the inverter compressor is made during the individual cooling of one of the storage compartments having the higher set temperature, stopping the deceleration function of the inverter compressor.