Portable Ice Making Apparatus Having a Bypass Tube

Abstract

This invention relates to a portable onsite ice making apparatus having a bypass tube, which includes a compressor equipped with a condenser having heat removal capacity of about 2,400˜2,600 BTU/hr; an expansion valve; an evaporator being in heat exchange relationship with an ice making tray; a bypass tube for the refrigerant to bypass the condenser and the expansion valve; and a switching means selectively changing the flow of the refrigerant from the compressor to the condenser or from the compressor to the bypass tube. The portable ice making apparatus has heat removal capacity to cool the ice making tray to −27° C.˜−26° C. within 3 minutes and heating capacity to heat the ice making tray from about −27° C.˜−26° C. to about 50° C.˜−60° C. within 30 seconds. The area of the capillary tube in the bypass tube to the area of the first discharging tube is about 1/25˜ 1/10.

What is claimed is: 
     
         1 . A portable ice making apparatus having a bypass tube comprising:
 a compressor equipped with a condenser wherein a first discharging tube connects the compressor to the condenser for delivering a refrigerant from the compressor to the condenser;   an expansion valve wherein a second discharging tube connects the condenser to the expansion valve for delivering the refrigerant from the condenser to the expansion valve;   an evaporator being in heat exchange relationship with an ice making tray wherein the evaporator is connected to the expansion valve by an inlet tube and to the compressor by an outlet tube;   a bypass tube which connects the first discharging tube to the inlet tube for making the refrigerant bypass the condenser and the expansion valve; and   a switching means installed at the intersection of the first discharging tube and the bypass tube for selectively changing the flow of the refrigerant from the compressor to the condenser or from the compressor to the bypass tube;   
       wherein the ice making tray is placed on a coolant pipe of the evaporator. 
     
     
         2 . The portable ice making apparatus of  claim 1  wherein the compressor equipped with the condenser has heat removal capacity of about 2,400˜2,600 BTU/hr. 
     
     
         3 . The portable ice making apparatus of  claim 1  wherein the portable ice making apparatus has heat removal capacity to cool the ice making tray from 15° C.˜−25° C. to −27° C.˜26° C. within 3 minutes. 
     
     
         4 . The portable ice making apparatus of  claim 1  wherein the bypass tube is configured to have a capillary tube. 
     
     
         5 . The portable ice making apparatus of  claim 4  wherein the diameter of the cross section of the capillary tube is about 2˜3 mm. 
     
     
         6 . The portable ice making apparatus of  claim 5  wherein the capillary tube is coiled. 
     
     
         7 . The portable ice making apparatus of  claim 6  wherein the ratio of the sectional area of the capillary tube to the sectional area of the first discharging tube is about 1/25˜ 1/10. 
     
     
         8 . The portable ice making apparatus of  claim 1  wherein the diameter of the cross section of the first discharging tube is about 9˜10 mm. 
     
     
         9 . The portable ice making apparatus of  claim 1  wherein the portable ice making apparatus has heating capacity to heat the ice making tray from about −27° C.˜−26° C. to about 50° C.˜−60° C. within 30 seconds. 
     
     
         10 . The portable ice making apparatus of  claim 1  wherein the switching means is a three-way valve. 
     
     
         11 . The portable ice making apparatus of  claim 1 , further comprising a temperature sensor which is installed at the ice making tray to sense the temperature of the ice making tray. 
     
     
         12 . The portable ice making apparatus of  claim 11  wherein the compressor is turned off when the temperature sensed by the temperature sensor is below a first predetermined temperature. 
     
     
         13 . The portable ice making apparatus of  claim 12  wherein the first predetermined temperature is about −27° C. 
     
     
         14 . The portable ice making apparatus of  claim 11  wherein the compressor is turned off when the temperature sensed by the temperature sensor is above a second predetermined temperature. 
     
     
         15 . The portable ice making apparatus of  claim 14  wherein the second predetermined temperature is about 60° C. 
     
     
         16 . The portable ice making apparatus of  claim 1  wherein the coolant pipe is configured to have a shape of circular coil in that the inlet tube is split into two sub-inlet tubes and the outlet tube is split into two sub-outlet tubes wherein inlet points of the two sub-inlet tubes are located about the same distance from the center of the circular coil and wherein one of outlet points of the two sub-outlet tubes is located at the center of the circular coil and the other outlet point of the two sub-outlet tubes is located at the outer boundary of the circular coil. 
     
     
         17 . A portable ice making apparatus having a bypass tube comprising:
 a compressor equipped with a condenser wherein a first discharging tube connects the compressor to the condenser for delivering a refrigerant from the compressor to the condenser;   an expansion valve wherein a second discharging tube connects the condenser to the expansion valve for delivering the refrigerant from the condenser to the expansion valve;   an evaporator being in heat exchange relationship with an ice making tray wherein the evaporator is connected to the expansion valve by an inlet tube and to the compressor by an outlet tube;   a bypass tube which connects the first discharging tube to the evaporator for making the refrigerant bypass the condenser and the expansion valve; and   a switching means installed at the intersection of the first discharging tube and the bypass tube for selectively changing the flow of the refrigerant from the compressor to the condenser or from the compressor to the bypass tube;   wherein the ice making tray is placed on a coolant pipe of the evaporator.   
     
     
         18 . The portable ice making apparatus of  claim 17  wherein the compressor equipped with the condenser has heat removal capacity of about 2,400˜2,600 BTU/hr. 
     
     
         19 . The portable ice making apparatus of  claim 17  wherein the bypass tube is configured to have a capillary tube and the ratio of the sectional area of the capillary tube to the sectional area of the first discharging tube is about 1/25˜ 1/10. 
     
     
         20 . The portable ice making apparatus of  claim 17  wherein the coolant pipe is configured to have a shape of a circular coil in that the inlet tube is split into two sub-inlet tubes and the outlet tube is split into two sub-outlet tubes wherein inlet points of the two sub-inlet tubes are located about the same distance from the center of the circular coil and wherein one of outlet points of the two sub-outlet tubes is located at the center of the circular coil and the other outlet point of the two sub-outlet tubes is located at the outer boundary of the circular coil.