Patent Publication Number: US-6907663-B2

Title: Refrigerator and method for manufacturing heat pipe unit of refrigerator

Description:
CLAIM OF PRIORITY 
   This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from my application entitled  REFRIGERATOR AND MANUFACTURING METHOD OF HEAT PIPE THEREOF  filed with the Korean Industrial Property Office on 13 Jul. 2000 and there duly assigned Ser. No. 2000/40266. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a refrigerator having an improved heating system of an evaporator and a heater, and a method for manufacturing a heat pipe unit of the refrigerator. 
   2. Description of the Related Art 
   Generally, a refrigerator is comprised of a main body formed with a storage chamber accommodating food therein, and a cooling system provided in the main body, cooling the food accommodated within the storage chamber. 
   For the convenience&#39;s sake to describe the present invention, a kimchi refrigerator comprising a cooling system cooling the storage chamber and a heater raising an inner temperature of the storage chamber will be described by way of example. 
   Referring to  FIG. 10  which is a sectional view of a conventional kimchi refrigerator, the conventional kimchi refrigerator  101  is comprised of a main body  103  having an opening on its top and a door  105  opening and closing the opening. 
   The main body  103  is comprised of an outer casing  110  defining an outer appearance of the refrigerator, and an inner casing  111  of a cylinder shape accommodated within the outer casing  110 , forming a storage chamber  121 . Foaming material is filled between the outer casing  110  and the inner casing  111 . 
   On the front upper portion of the outer casing  110  is provided a control panel (not shown) allowing a user to control an operation mode of the kimchi refrigerator to a storage mode or a ripeness mode. In the lower portion of the main body  103  is provided a component chamber  113  accommodating therein devices and units to operate the kimchi refrigerator. 
   Within the component chamber  113  are installed a compressor  123  compressing a refrigerant to a high temperature and high pressure state, and a condenser (not shown) condensing the compressed refrigerant from the compressor  123  to a low temperature and low pressure state, etc. Alternatively, the condenser may be installed in the space to be filled with the foaming material, formed between the outer casing  110  and the inner casing  111 . 
   On an outer wall of the inner casing  111  are installed an evaporator pipe  133  cooling the inside of the storage chamber  121  by means of the refrigerant supplied from the compressor  123 , and a heater pipe  135  raising an inner temperature of the storage chamber  121  to ripen the food accommodated in the storage chamber  121 , so as to surround an inner wall of the inner casing  111 . Inside the heater pipe  135  is accommodated a hot wire  145  generating heat by means of an electric power supplied from a power supply (not shown). 
   With this configuration, if the storage mode is selected, a low-temperature refrigerant flows into inside of the evaporator pipe  133 , and cool air from the refrigerant flowing inside of the evaporator pipe  133  is transmitted to the inner casing  111 , thereby cooling the inside of the storage chamber  121 . If the ripeness mode is selected, supply of the refrigerant from the evaporator pipe  133  is suspended, and an electric power is supplied to the heater pipe  135 , thereby generating heat from the hot wire  145 . The heat generated from the hot wire  145  is transmitted to the inner casing  111  surrounded by the heater pipe  135 , thereby increasing the inner temperature of the storage chamber  121 . While the refrigerator  101  is being in operation under the storage mode, frost may be produced on the evaporator pipe  133 . A defrost mode activating the heater pipe  135  to remove the frost from the evaporator pipe  133  is conducted. 
   In the conventional kimchi refrigerator, the evaporator pipe and the heater pipe have been manufactured separately, and the cooling and heating functions have been conducted independently, and therefore, the evaporator pipe occupies a cooling surface area for itself relative to the inner casing, and the heater pipe also occupies a heating surface area for itself relative to the inner casing. Where the refrigerator is under the storage mode, a cooling function is supplied in proportion to the cooling surface area of the evaporator pipe. Where the refrigerator is under the ripeness mode and the defrost mode, a heating function is only supplied in correspondence with the heater pipe. Therefore, where the refrigerator is under the storage, ripeness or defrost mode, if both the cooling and heating surface areas corresponding to the evaporator pipe and the heater pipe respectively can be used, the cooling, ripening and defrosting functions may be more improved. 
   In the conventional kimchi refrigerator, the separate manufacturing of the evaporator pipe and the heater pipe leads to lowering the productivity. In addition, working time to install the evaporator pipe and the heater pipe is prolonged. If the evaporator pipe and the heater pipe can be manufactured in a single unit, this will reduce the number of processes for the production thereof and the time for installation thereof, thereby improving the productivity. 
   SUMMARY OF THE INVENTION 
   The present invention has been made keeping in mind the above-described shortcomings, and accordingly, an object of the present invention is to provide a refrigerator having improved cooling, ripening and defrosting functions, and improving the productivity, and a method for manufacturing a heat pipe unit for the refrigerator. 
   This and other objects of the present invention may be achieved by a provision of a refrigerator comprising an outer casing defining an outer appearance thereof, and an inner casing accommodated in the outer casing, forming a storage chamber, the refrigerator further comprising a heat pipe unit having an evaporator pipe disposed to surround at least one portion of the inner casing, forming a refrigerant path, a heater pipe disposed in parallel with the evaporator pipe, and a connection part connecting the evaporator pipe and the heater pipe, enabling a heat transfer therebetween. 
   The heat pipe unit is comprised of a bent part to correspond to the shape of the inner casing. 
   The connection part is of a plate shape, being formed between the evaporator pipe and the heater pipe longitudinally relative to the heat pipe unit. 
   A portion of the connection part corresponding to the bent part is cut off. 
   The refrigerator further comprises a heat plate disposed between the inner casing and the heat pipe unit, to surround an outer wall of the inner casing. 
   The evaporator pipe, the heater pipe and the connection part are contacted with the heat plate. 
   The evaporator pipe, the heater pipe and the connection part are formed in a single unit. 
   The refrigerator further comprises a hot wire received within the heater pipe. 
   The heat pipe unit is formed of a roll-bond type having the evaporator pipe and the heater pipe between a pair of metal plates in contact with each other. 
   According to another aspect of the present invention, this and other objects may be achieved by a provision of a method for manufacturing a heat pipe unit for a refrigerator comprising a main body formed with an outer casing defining an outer appearance thereof and an inner casing accommodated in the outer casing, forming a storage chamber, the method comprising the steps of preparing a raw material with predetermined width and length; forming a heat pipe unit integrally formed with an evaporator pipe forming a refrigerant path, a heater pipe in parallel with the evaporator pipe, and a connection part connecting the evaporator pipe and the heater pipe so as to enable the heat transfer therebetween, by processing the raw material; and disposing the heat pipe unit to surround the inner casing. 
   The heat pipe unit has a bent part to correspond in shape to the inner casing. 
   The connection part takes a plate shape and is connected to the evaporator pipe and the heater pipe longitudinally relative to the heat pipe unit. 
   The method further comprises the steps of determining a position to be bent, according to a longitudinal direction of the heat pipe unit; cutting off a portion of the connection part corresponding to the bent position; and bending the heat pipe unit zigzag. 
   The method further comprises the step of accommodating a hot wire within the heater pipe. 
   The method further comprises the step of bending the bent heat pipe unit to enclose an outer wall of the inner casing. 
   The method further comprises the step of providing a heat plate between the inner casing and the heat pipe unit, to enclose the outer wall of the inner casing. 
   The method further comprises the step of mounting the heat pipe unit on the heat plate. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
       FIG. 1  is a sectional view of a kimchi refrigerator having a heat pipe unit according to the present invention; 
       FIG. 2  is an enlarged sectional view of “A” of  FIG. 1 ; 
       FIG. 3  is a partial sectional view of the heat pipe unit according to another embodiment of the present invention; 
       FIG. 4  is a flow chart of a method for producing the heat pipe unit of  FIG. 1 ; 
       FIGS. 5 through 9  are schematic views briefly showing processes of manufacturing the heat pipe unit of  FIG. 4 ; and 
       FIG. 10  is a sectional view of a conventional kimchi refrigerator. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring to  FIGS. 1 and 2 , a kimchi refrigerator  1  according to the present invention is comprised of a main body  3  formed with an opening through which food is put in and taken out, and a door  5  opening and closing the opening of the main body  3 . 
   The main body  3  is comprised of an outer casing  10  defining an outer appearance of the refrigerator  1 , and an inner casing  11  of a cylinder shape accommodated within the outer casing  10 , forming a storage chamber  21 . A foaming material  7  is filled between the outer casing  10  and the inner casing  11 . On a front top face of the outer casing  10  is formed a control panel (not shown) controlling an operation of the kimchi refrigerator  1  according to the kind of the food accommodated within the storage chamber. In the lower portion of the main body  3  is installed a component chamber  13  accommodating therein devices and units to operate the kimchi refrigerator  1 . 
   Within the component chamber  13  are installed a compressor  23  compressing a refrigerant to a high temperature and high pressure state, and a condenser (not shown) condensing the compressed refrigerant from the compressor  123  to a low temperature and low pressure state, etc. Alternatively, the condenser may be installed in the space to be filled with the foaming material, formed between the outer casing  10  and the inner casing  11 . 
   In the space filled with the foaming material  7  between the outer casing  10  and the inner casing  11  is installed a heat pipe unit  30  cooling and heating an inner temperature of the storage chamber  21  according to a mode selected from the control panel. Between the inner casing  11  and the heat pipe unit  30  is disposed a metallic heat plate  40  surrounding the inner casing  11 . 
   As shown in  FIG. 3 , the heat pipe unit  30  may be manufactured as a roll-bond type comprising an evaporator pipe  53  forming a refrigerant path between a pair of metal plates contacted with each other, and a heater pipe  55  accommodating a hot wire  65  therein. 
   An inlet of the evaporator pipe  33  is connected to a refrigerant pipe (not shown) extended from a capillary tube (not shown), and an outlet of the evaporator pipe  33  is connected to a refrigerant pipe extended toward the compressor  23 . Inside of the heater pipe  35  is accommodated a hot wire  45  electrically connected to a power supply (not shown). The connection part  37  of a plate shape, whose ends are connected to the evaporator pipe  33  and the heater pipe  35  in a single unit, is formed longitudinally relative to the heat pipe unit  30 . 
   The heat pipe unit  30  is constructed such that one sides of the evaporator pipe  33 , the heater pipe  35  and the connection part  37  contact the heat plate  40 , to thereby increase the efficiency of a heat transfer. The heat pipe unit  30  is comprised of a bent part “B” which is bent to correspond to the shape of the inner casing  11 . The connection part  37  corresponding to the bent part “B” is cut off to facilitate its bending. 
   As shown in  FIG. 3 , the heat pipe unit  30  may be manufactured as a roll-bond type comprising an evaporator pipe  53  forming a refrigerant path between a pair of metal plates contacted with each other, and a heater pipe  55  accommodating a hot wire  65  therein. 
   With this configuration, while the refrigerator is in the storage mode, if the low-temperature refrigerant flows into inside of the evaporator pipe  33 , the cool air from the refrigerant flowing along the evaporator pipe  33  is transmitted to the heater pipe  35  through the connection part  37 . Subsequently, the cool air is transmitted to the whole area of the heat pipe unit  30  through the evaporator pipe  33 , the heater pipe  35  and the connection part  37 , and the transferred cool air is transmitted to the inner casing  11  through the heat plate  40 , to thereby cool the storage chamber  21 . Accordingly, the heating surface area of the cool air from the refrigerant flowing along the evaporator pipe  33  is increased, thereby increasing an efficiency of cooling. 
   If a ripeness mode is selected, supply of the refrigerant to the evaporator pipe  33  is suspended, and an electric power is supplied to the hot wire  45  received in the heater pipe  35 , to generate heat from the heater pipe  35 . The generated heat is transmitted to the evaporator pipe  33  through the connection part  37 , to thereby heat the whole area of the heat pipe unit  30 . This heat is transmitted into the inner casing  11  through the heat plate  40 , to increase an inner temperature of the storage chamber  21 . Accordingly, the heating surface area for the heat from the heater pipe  35  is increased, thereby increasing an efficiency of ripening. 
   A defrost mode may be operated to remove frost generated on the evaporator pipe  33  before the ripeness mode is selected. While the refrigerator is in the defrost mode, the heat generated from the heater pipe  35  is transmitted to the evaporator pipe  33  directly from the connection part  37 , so that the frost on the evaporator pipe  33  is quickly removed, thereby improving an efficiency of the defrosting. 
   A method for manufacturing the heat pipe unit of the refrigerator of  FIG. 1  will be described with reference to  FIGS. 4 and 5 . 
   First, a raw material for the heat pipe unit with predetermined length and width is provided (S 01 ). By injection molding or drawing molding of the raw material, the heat pipe unit  30  is formed integrally with the evaporator pipe  33 , the heater pipe  35  and a connection part  37 , as shown in  FIG. 5  (S 02 ). The connection part  37  of a plate shape is structured between the evaporator pipe  33  and the heater pipe  35  longitudinally relative to the heat pipe unit  31 . 
   Once the heat pipe unit  30  is formed, the hot wire  45  is then inserted into the heater pipe  35  (S 03 ). Thereafter, the bent part “B” of the heat pipe unit  30  is determined to correspond to the shape of the inner casing  11  of the kimchi refrigerator  1  (S 04 ). If the bent part “B” is determined, the connection part  37  for the bent part “B” is cut off as seen in  FIG. 6  (S 05 ). If the connection part  37  for the bent part “B” is cut off, the heat pipe unit  30  is bent zigzag from the planar shape, as shown in  FIGS. 7 and 8  (S 06 ). As shown in  FIG. 9 , the portion of “C” is bent to correspond to the circumference of the inner casing  11  of the kimchi refrigerator  1 , to thereby finish manufacturing the heat pipe unit  30  (S 07 ). 
   Prior to installing the heat pipe unit  30  at the inner casing  10 , the metallic heat plate  40  is manufactured (S 08 ). The manufactured heat plate  40  is installed to surround an outer wall of the inner casing  11  (S 09 ), and thereafter, the heat pipe unit  30  is attached to the outer surface of the heat plate  40  (S 10 ). 
   By producing a heat pipe unit integrally formed with the evaporator pipe forming the refrigerant path, the heater pipe generating heat, and the connection part connecting the evaporator pipe and the heater pipe so as to enable the heat transfer therebetween, the processes of producing and installing those devices and units having functions of cooling and heating are simplified, thereby increasing the productivity. 
   As described above, according to the present invention, there are provided a refrigerator enhancing cooling, ripeness and defrost performances and the productivity, and a method for manufacturing a heat pipe unit for the refrigerator. 
   Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.