Variable volume receiver for refrigerating cycle, refrigerating cycle comprising the variable receiver, and method for controlling the refrigerating cycle

Abstract

A variable volume receiver for a refrigerating cycle, according to the present invention, can adjust the capacity of storing a refrigerant according to changes in driving conditions, such as outside air temperature or a load-side temperature, and can secure a proper degree of sub-cooling even when the driving conditions change, thereby providing the advantage of enabling optimum driving regardless of changes in the outside air temperature or the load-side temperature.

1 . A variable volume receiver for a refrigerating cycle, comprising:
 a receiver tank that is connected to a refrigerant flow path and constitutes a refrigerant storing space in which the refrigerant that passes through the refrigerant flow path is temporarily stored;   a variable bladder that is disposed in the receiver tank and is contracted or expanded so that a volume of the refrigerant storing space is reduced or decreased;   a pressure-controlling portion that is installed separately from the refrigerant flow path, communicates with the variable bladder, is sealed from an outside and controls pressure in the variable bladder when a fluid that communicates with the variable bladder and is filled in the variable bladder receives heat of the refrigerant at an outlet of a compressor in the refrigerating cycle; and   a controller that controls the pressure-controlling portion according to driving conditions, changes the volume of the refrigerant storing space and controls an amount of the refrigerant that is capable of being stored in the refrigerant storing space.   
     
     
         2 . A variable volume receiver for a refrigerating cycle, comprising:
 a receiver tank that is connected to a refrigerant flow path and constitutes a refrigerant storing space in which the refrigerant that passes through the refrigerant flow path is temporarily stored;   a piston that is coupled to the receiver tank so as to linearly make a reciprocating motion and increases or reduces a volume of the refrigerant storing space while linearly making a reciprocating motion;   a linearly moving mechanism that linearly makes a reciprocating motion of the piston; and   a controller that controls the linearly moving mechanism according to driving conditions, changes the volume of the refrigerant storing space and controls an amount of the refrigerant that is capable of being stored in the refrigerant storing space.   
     
     
         3 . A refrigerating cycle comprising a compressor, a condenser, an expansion mechanism, an evaporator, and a controller, further comprising a variable volume receiver, wherein the variable volume receiver comprises a refrigerant storing portion which is installed on a refrigerant flow path that connects the condenser and the expansion mechanism and in which a refrigerant discharged from the condenser is temporarily stored, and a volume-controlling portion controls a volume of the refrigerant storing portion while being contracted or expanded by a pressure-controlling portion that is installed separately from the refrigerant flow path and sealed from an outside, and
 the controller controls pressure of a fluid in the volume-controlling portion according to driving conditions, changes the volume of the refrigerant storing portion and controls an amount of the refrigerant stored in the variable volume receiver.   
     
     
         4 . A refrigerating cycle comprising a compressor, a condenser, an expansion mechanism, an evaporator, and a controller, further comprising a variable volume receiver, wherein the variable volume receiver comprises a receiver tank that is installed on a refrigerant flow path that connects the condenser and the expansion mechanism and constitutes a refrigerant storing space in which a refrigerant discharged from the condenser is temporarily stored, a variable bladder that is disposed in the receiver tank and reduces or increases a volume of the refrigerant storing space while being contracted or expanded, and a pressure-controlling portion that is installed separately from the refrigerant flow path, communicates with the variable bladder, is sealed from an outside and controls pressure in the variable bladder when a fluid filled in the variable bladder receives heat of the refrigerant at an outlet of the compressor, and
 the controller calculates a degree of sub-cooling according to temperature and pressure of the refrigerant at an outlet of the condenser and controls the pressure-controlling portion according to the calculated degree of sub-cooling.   
     
     
         5 . A refrigerating cycle comprising a compressor, a condenser, an expansion mechanism, an evaporator, and a controller, further comprising a variable volume receiver, wherein the variable volume receiver comprises a receiver tank that is connected to a refrigerant flow path and constitutes a refrigerant storing space in which a refrigerant that passes through the refrigerant flow path is temporarily stored, a piston that is coupled to the receiver tank so as to linearly make a reciprocating motion and increases or reduces a volume of the refrigerant storing space while linearly making a reciprocating motion, and a linearly moving mechanism that linearly makes a reciprocating motion of the piston, and
 the controller calculates a degree of sub-cooling according to temperature and pressure of the refrigerant at an outlet of the condenser and controls the linearly moving mechanism according to the calculated degree of sub-cooling.   
     
     
         6 . The refrigerating cycle of  claim 4 , wherein the pressure-controlling portion comprises a pressure-controlling pipe which communicates with the variable bladder and in which a fluid that is evaporated by receiving heat of a high-temperature refrigerant at the outlet of the compressor is filled. 
     
     
         7 . The refrigerating cycle of  claim 4 , wherein the pressure-controlling portion comprises a pressure-controlling pipe which communicates with the variable bladder and in which the fluid is filled; and
 a heat-exchanging portion that is installed at a discharging side of the compressor and performs or blocks heat-exchanging between the high-temperature refrigerant at the outlet of the compressor and the fluid of the pressure-controlling pipe according to signals of the controller.   
     
     
         8 . The refrigerating cycle of  claim 7 , wherein the heat-exchanging portion comprises a linearly moving mechanism that linearly moves at least one of the discharging pipe of the compressor and the pressure-controlling pipe to be spaced apart from each other so that a distance between the discharging pipe of the compressor and the pressure-controlling pipe is adjusted according to signals of the controller. 
     
     
         9 . The refrigerating cycle of  claim 8 , wherein the linearly moving mechanism comprises a rack coupled to the pressure-controlling pipe, a pinion engaged with the rack, and a motor that rotates the pinion according to signals of the controller. 
     
     
         10 . The refrigerating cycle of  claim 8 , wherein the linearly moving mechanism comprises a magnetic body installed at one of the pressure-controlling pipe and the discharging pipe of the compressor, an electromagnet installed at the other one thereof, and a power supplying portion that applies power to the electromagnet according to signals of the controller. 
     
     
         11 . The refrigerating cycle of  claim 7 , wherein the heat-exchanging portion comprises an insulating sheet that linearly makes a reciprocating motion between the discharging pipe of the compressor and the pressure-controlling pipe and prevents heat of the discharging pipe of the compressor from being transferred to the pressure-controlling pipe, and a linearly moving mechanism that linearly makes a reciprocating motion of the insulating sheet according to signals of the controller. 
     
     
         12 . The refrigerating cycle of  claim 7 , wherein the heat-exchanging portion comprises a heat transfer sheet that linearly makes a reciprocating motion between the discharging pipe of the compressor and the pressure-controlling pipe according to signals of the controller and transfers heat of the discharging pipe of the compressor to the pressure-controlling pipe, and a linearly moving mechanism that linearly makes a reciprocating motion of the heat transfer sheet. 
     
     
         13 . The refrigerating cycle of  claim 4 , wherein the pressure-controlling portion comprises:
 a pressure-controlling pipe which communicates with the variable bladder and in which the fluid is filled;   a refrigerant bypass flow path on which the refrigerant at the outlet of the compressor is bypassed toward the pressure-controlling pipe; and   a bypass valve that opens/closes the refrigerant bypass flow path.   
     
     
         14 . The refrigerating cycle of  claim 7 , wherein
 the pressure-controlling pipe comprises a capillary flow path.   
     
     
         15 . The refrigerating cycle of  claim 7 , wherein
 the fluid is used the same refrigerant on the refrigerant flow path.   
     
     
         16 . The refrigerating cycle of  claim 7 , wherein a volume expansion coefficient of the fluid filled in the pressure-controlling pipe and the variable bladder is equal to or greater than a volume expansion coefficient of the refrigerant. 
     
     
         17 . A method for controlling a refrigerating cycle, comprising:
 a degree of sub-cooling calculating operation of calculating a degree of sub-cooling by measuring temperature and pressure of a refrigerant at an outlet of a condenser; and   a volume-controlling operation of increasing or reducing a volume of a refrigerant storing portion of a variable volume receiver according to the calculated degree of sub-cooling by controlling pressure of a fluid filled in a volume-controlling portion of the variable volume receiver using heat of the refrigerant at an outlet of a compressor,   wherein the volume-controlling operation comprises:   if the calculated degree of sub-cooling is equal to or greater than a predetermined degree of sub-cooling, preventing heat of the refrigerant at the outlet of the compressor from being transferred to the fluid filled in the volume-controlling portion, thereby reducing pressure in the volume-controlling portion and increasing the volume of the refrigerant storing portion; and   if the calculated degree of sub-cooling is less than the predetermined degree of sub-cooling, increasing pressure in the volume-controlling portion and reducing the volume of the refrigerant storing portion when the fluid filled in the volume-controlling portion receives heat of the refrigerant at the outlet of the compressor.   
     
     
         18 . The refrigerating cycle of  claim 13 , wherein the pressure-controlling pipe comprises a capillary flow path. 
     
     
         19 . The refrigerating cycle of  claim 13 , wherein the fluid is used the same refrigerant on the refrigerant flow path. 
     
     
         20 . The refrigerating cycle of  claim 13 , wherein a volume expansion coefficient of the fluid filled in the pressure-controlling pipe and the variable bladder is equal to or greater than a volume expansion coefficient of the refrigerant.