Refrigerator and driving method thereof

Abstract

A refrigerator and a driving method thereof are disclosed. The number of vibration of each compressor, evaporation temperature of each evaporator, or an open time of a refrigerant switching valve is detected to determine whether the flow of refrigerant is biased so as to adjust a cooling capability of the compressor or an open value or open time of a refrigerant switching valve, thereby uniformly distributing the refrigerant into first and second evaporators. Accordingly, the refrigerator can be driven with an independent refrigeration cycle corresponding to a load of a freezing chamber or a refrigerating chamber, resulting in reduction of unnecessary power consumption of the refrigerator.

1 . A refrigerator comprising:
 a plurality of compressors sequentially connected to perform a multi-stage compression for a refrigerant;   a condenser connected to an outlet side of a secondary compressor of the plurality of compressors, the secondary compressor located at a downstream based on the flowing direction of the refrigerant;   a first evaporator diverged from the condenser and connected to an inlet side of a primary compressor of the plurality of compressors, the primary compressor located at an upstream based upon the flowing direction of the refrigerant;   a second evaporator diverged from the condenser together with the first evaporator and connected between an outlet side of the primary compressor and an inlet side of the secondary compressor;   a refrigerant switching valve installed such that an inlet side of the first evaporator and an inlet side of the second evaporator are connected to an outlet side of the condenser in parallel and configured to control the flowing direction of the refrigerant toward the first evaporator or the second evaporator;   a refrigerant amount detecting unit configured to detect an amount of refrigerant introduced into the first or second evaporator; and   a refrigerant amount adjusting unit configured to adjust amounts of refrigerant flowing toward the first and second evaporators, respectively, according to the result detected by the refrigerant amount detecting unit.   
     
     
         2 . The refrigerator of  claim 1 , wherein the refrigerant amount detecting unit comprises a plurality of vibration sensors installed at the primary compressor and the secondary compressor, respectively, to detect changes in the number of vibration of each of the primary and secondary compressors. 
     
     
         3 . The refrigerator of  claim 2 , wherein the refrigerant amount adjusting unit comprises a micom electrically connected to the vibration sensors to determine to which evaporator the amount of refrigerant is biased according to the number of vibration detected by each vibration sensor, and increase a cooling capability of a compressor having an inlet side connected to the outlet side of an evaporator, to which more refrigerant flows. 
     
     
         4 . The refrigerator of  claim 1 , wherein the refrigerant amount detecting unit comprises a plurality of temperature sensors installed at the first and second evaporators, respectively, and configured to detect temperature changes of the first and second evaporators. 
     
     
         5 . The refrigerator of  claim 4 , wherein the refrigerant amount adjusting unit comprises a micom electrically connected to the temperature sensors to determine to which evaporator the amount of refrigerant is biased according to evaporation temperatures of the respective evaporators detected by the temperature sensors, and control an open value of the refrigerant switching valve to reduce the amount of refrigerant introduced into an evaporator, to which it is determined more refrigerant flows. 
     
     
         6 . The refrigerator of  claim 1 , wherein the refrigerant amount detecting unit comprises a timer electrically connected to the refrigerant switching valve and configured to detect an open time of the refrigerant switching valve. 
     
     
         7 . The refrigerator of  claim 6 , wherein the refrigerant amount adjusting unit comprises a micom electrically connected to the timer to determine to which evaporator the amount of refrigerant is biased according to the open time of the refrigerant switching valve detected by the timer, and control the open time of the refrigerant switching valve to reduce the amount of refrigerant introduced into an evaporator to which it is determined more refrigerant flows. 
     
     
         8 . The refrigerator of  claim 1 , wherein the secondary compressor is large in capacity than the primary compressor. 
     
     
         9 . The refrigerator of  claim 1 , wherein the first evaporator is installed to supply cold air into a freezing chamber, and the second evaporator is installed to supply cold air into a refrigerating chamber. 
     
     
         10 . A driving method for a refrigerator comprising:
 detecting the number of vibration of each of primary and secondary compressors sequentially connected to each other;   determining whether the amount of refrigerant is biased by comparing the detected number of vibration with a reference value set in a micom; and   increasing a cooling capability of a compressor, to which it is determined more refrigerant flows.   
     
     
         11 . The method of  claim 10 , wherein at the step of detecting the number of vibration of each of the primary and secondary compressors, the number of vibration of the primary compressor located relatively at an upstream is first detected to determine whether the flow of refrigerant is biased toward the primary compressor, and a driving for increasing the cooling capability of the primary compressor is carried out when the detected number of vibration of the primary compressor exceeds the reference value,
 wherein when the detected number of vibration of the primary compressor does not exceed the reference value, the number of vibration of the secondary compressor is detected to determine whether the flow of refrigerant is biased toward the secondary compressor, and a driving for increasing the cooling capability of the secondary compressor is carried out when the detected number of vibration of the secondary compressor exceeds the reference value.   
     
     
         12 . A driving method for a refrigerator comprising:
 detecting evaporation temperatures of first and second evaporators connected to a condenser in parallel;   determining whether or not a flow of refrigerant is biased by comparing the detected evaporation temperatures with a reference temperature; and   adjusting an open value of a refrigerant switching valve to reduce the amount of refrigerant introduced into an evaporator to which it is determined more refrigerant flows.   
     
     
         13 . The method of  claim 12 , wherein at the step of detecting the evaporation temperatures of the primary and secondary compressors, the evaporation temperatures of the first evaporator are first detected to determine whether the flow of refrigerant is biased toward the first evaporator, and a driving for reducing an open value of the refrigerant switching valve toward the first evaporator is carried out when the evaporation temperatures of the first evaporator exceed a reference evaporation temperature,
 wherein when the detected evaporation temperatures of the first evaporator are lower than the reference evaporation temperature, the evaporation temperatures of the second evaporator are detected to determine whether the flow of refrigerant is biased toward the second evaporator, and a driving for reducing an open value of the refrigerant switching valve toward the second evaporator is carried out when the detected evaporation temperatures of the second evaporator exceed the reference evaporation temperature.   
     
     
         14 . A driving method for a refrigerator comprising:
 detecting an open time of a refrigerant switching valve with respect to each of first and second evaporators, the refrigerant switching valve installed to allow the first and second evaporators to be connected to a condenser in parallel;   determining whether a flow of refrigerant is biased by comparing the detected open time with a reference open time; and   adjusting the open time of the refrigerant switching valve to reduce the amount of refrigerant introduced into an evaporator to which more refrigerant flows.   
     
     
         15 . The method of  claim 15 , wherein at the step of detecting the open times of the first and second evaporators, the open time for the first evaporator is first detected to determine whether the flow of refrigerant is biased toward the first evaporator, and a driving for reducing the open time of the refrigerant switching valve toward the first evaporator is carried out when the detected open time for the first evaporator exceeds the reference open time,
 wherein when the detected open time for the first evaporator does not exceed the reference open time, the open time for the second evaporator is detected to determine whether the flow of refrigerant is biased toward the second evaporator, and a driving for reducing the open time of the refrigerant switching valve toward the second evaporator is carried out when the detected open time for the second evaporator exceeds the reference open time.   
     
     
         16 . A driving method for a refrigerator having a freezing chamber refrigeration cycle comprising a plurality of compressors sequentially connected to each other, and a refrigerating chamber refrigeration cycle comprising a compressor located at a downstream of the plurality of compressors,
 wherein one of the number of vibration, evaporation temperatures or a flow of refrigerant is measured with respect to the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle, to control the amount of refrigerant flowing between the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle.   
     
     
         17 . The method of  claim 16 , wherein the number of vibration of each of the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle is obtained by measuring the number of vibration of each of the plurality of compressors. 
     
     
         18 . The method of  claim 16 , wherein the evaporation temperatures of the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle are obtained by measuring evaporation temperatures of each evaporator independently connected to the plurality of compressors. 
     
     
         19 . The method of  claim 16 , wherein the flow of refrigerant of the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle is obtained by measuring an open time of a valve, the valve controlling a flowing direction of the refrigerant between the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle. 
     
     
         20 . The method of  claim 16 , wherein the flow of refrigerant between the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle is controlled by adjusting a cooling capability of each compressor. 
     
     
         21 . The method of  claim 16 , wherein the flow of refrigerant between the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle is controlled by adjusting an open value or an open time of a valve, the valve controlling the flowing direction of the refrigerant between the freezing chamber refrigeration cycle and the refrigerating chamber refrigeration cycle.