In the state of art, said fresh-food and freezer compartments are cooled by means of an evaporator and a fan placed in the freezer compartment. The cold air in the freezer compartment is transferred to the fresh-food compartment by means of a damper which is variably controlled between the open and closed positions and by the blowing of the fan. The damper located at the fresh-food compartment is opened or closed according to the information received from the temperature sensor located in the same compartment. In this case, the temperature in the fresh-food compartment varies between the minimum and maximum values as determined by the manufacturer and the damper is closed when the temperature in the fresh-food compartment reaches the lowest value and opens only when it reaches the maximum value.

In the US Patent No. 4843833, a control unit that receives information from the sensors located at the freezer-and fresh food-compartments, is disclosed.

When the temperature in the freezer compartment exceeds the limit value, the control unit activates the compressor and the fan and then opens or closes the damper depending on the level of temperature in the food compartment.

In the US Patent No. 4732010, a unitary control assembly that receives information from the sensors located at the freezer-and fresh food-compartments, is disclosed. When the temperature in the fresh food compartment exceeds the limit value, the damper is opened and the fan is activated. When the food compartment temperature drops below the limit value, the damper is closed.

When the freezer compartment temperature exceeds the limit value, the compressor is enabled.

The object of the present invention, is to improve the cooling efficiency in the refrigerators having fresh food and freezer compartments.

The method for improving the cooling efficiency realized to attain the above objective of the present invention has been illustrated in the attached drawings, wherein: Figure 1, is the schematic view of the refrigerator ; Figure 2, is the flow chart of the refrigerator control method, Figure 3, is the flow chart of an alternative refrigerator control method, Figure 4, shows the simultaneous graphics showing the change in the temperature values in the fresh food and freezer-compartments by time and the respective operations of the damper and the compressor.

The components shown in the drawings have been enumerated separately as shown below: 1. Freezer compartment 2. Fresh-food compartment 3. Freezer compartment temperature sensor 4. Fresh-food compartment temperature sensor 5. Damper 6. Fan 7. Compressor 8. Evaporator 9. Control unit

The refrigerator according to the present invention comprises, a freezer compartment (1) wherein food to be kept for a long time period is stored, a fresh food compartment (2) wherein fresh food and beverage are stored, a compressor (7) used to compress the cooling fluid to be circulated in the refrigerator to provide cooling, an evaporator (8) located in the freezer compartment (1) to provide the cooling of the interior air by absorbing heat from the inner air by the passage of the cooling fluid through it, and a fan (6) serving to circulate the cooled air. A freezer compartment temperature sensor (3) is provided in the freezer compartment (1) and a food compartment sensor (4) is provided in the fresh food compartment (2). Cold air passing over the evaporator (8) is used to cool the fresh food compartment (2). A damper (5) which is activated preferably by a motor is placed between the freezer compartment (1) and the fresh food compartment (1), in order to provide the transfer of cold air to the fresh food compartment (2). The refrigerator furthermore, comprises a control unit (9) that controls the compressor (7), fan (6) and motor damper (5) according to the information sent from the sensors (3 and 4).

In the operational cycle of the refrigerator, when the freezer compartment temperature detected by the freezer compartment temperature sensor (3), exceeds a value determined by the manufacturer, the control unit (9) activates the compressor (7) and the fan (6) and when the freezer compartment temperature drops to the desired temperature by means of the compressor (7) and the fan (6), the operation of the compressor (7) and the fan (6) is interrupted and the operational cycle of the refrigerator is thus completed. Cold air, obtained by the evaporator (8) located in the freezer compartment (1) is transferred to the interior of the freezer compartment (1) by means of a fan (6) placed over the evaporator (8). When the fresh food compartment (2) temperature exceeds a value determined by the manufacturer the damper (5) opens and provides the transfer of the cold air obtained on the evaporator (8) to the fresh food compartment (2).

In the method according to the invention, first the position of the damper (5), i. e. whether it is open or not, is checked in order to cool the fresh food compartment (2). (100). If the damper (5) is open, the fresh food compartment (TFC) should be compared with the minimum fresh food compartment (2) temperature value (TFC", ;") (101). Upon this compression procedure, if the fresh food compartment (2) temperature (TFC) is higher than the minimum fresh food compartment (2) temperature value (TFCmin), the damper (5) is opened (103); otherwise, i. e. in case the fresh food compartment (2) temperature (TFC) is lower than the minimum fresh food compartment (2) temperature value (TFCmin), the damper (5) is closed (102) and returned back to the first step (100). In the first step (100) where the position of the damper (5), i. e. whether it is open or not, is checked, if the damper (5) is closed, the fresh food compartment (2) temperature (TFC) is compared with the maximum fresh food compartment (2) temperature value (TFCmax) (104).

Upon this comparison procedure, if the fresh food compartment (2) temperature (TFC) is higher than the maximum fresh food compartment (2) temperature value (TFCmax) the damper (5) is opened (103) and returned to the step where the fresh food compartment (2) temperature (TFC) is compared with the minimum fresh food compartment (2) temperature value (TFCmin) (101). Upon this compression procedure, if the fresh food compartment (2) temperature (TFC) is higher than the minimum fresh food compartment (2) temperature value (TpCmin), the damper (5) stays open (103); otherwise, i. e. in case the fresh food compartment (2) temperature (TFC) is lower than the minimum fresh food compartment (2) temperature value (TFCmin), the damper (5) is closed (102) and returned back to the first step (100).

In step 104 where, the fresh food compartment (2) temperature (TFC) is compared with the maximum fresh food compartment (2) temperature value (TFCn, ax) if the fresh food compartment (2) temperature (TFC) is lower than the maximum fresh food compartment (2) temperature value (Tpcmax) the status of the compressor (7) i. e. whether it is operating or not, is controlled (105). If it is not operating, the process returns back to step 100 where the position of the

damper (5), i. e. whether it is open or not, is checked, if it is operating the damper (5) is opened (106) and the transfer of the cold air obtained on the evaporator (8) to the fresh food compartment (2) is provided. After this step, the fresh food compartment (2) temperature (TFC) is again compared with the minimum fresh food compartment (2) temperature value (TFCmin) (107). Upon this comparison procedure, if the fresh food compartment (2) temperature (TFC) is lower than the minimum fresh food compartment (2) temperature value (TFCmin) the damper (5) is closed (108) and returned back to the first step (100). If the fresh food compartment (2) temperature (TFC) is higher than the minimum fresh food compartment (2) temperature value (TFcmin) the status of the compressor (7) i. e. whether it is operating or not, is checked (109) to open or close the damper. If it is operating the damper (5) is opened (106), otherwise the damper (5) is closed (108) and returned back to the first step (100).

In another embodiment of the present invention, in step (104) where the fresh food compartment (2) temperature (TFC) is compared with the maximum fresh food compartment (2) temperature value (Tpcmax), if the fresh food compartment (2) temperature (TFC) is higher than the maximum fresh food compartment (2) temperature value (Tpcmax), the status of the compressor (7) i. e. whether it is operating or not, is controlled as well as whether the difference between the freezer compartment (1) temperature (TFR) and the minimum freezer compartment (1) temperature value (TFRmin) is smaller than the constant value (AT) which is determined by the manufacturer is checked (205). In this step, if the compressor (7) is operating and if the difference between the freezer compartment (1) temperature (TFR) and the minimum freezer compartment (1) temperature value (TFR. min) is smaller than the constant value (AT) which is determined by the manufacturer, the damper (5) is opened (106). Subsequent steps are the same as those in the previous embodiment. In step 205, where the status of the compressor (7) i. e. whether it is operating or not, is controlled as well as whether the difference between the freezer compartment (1) temperature (TFR) and the minimum freezer compartment (1) temperature value (TFR. min) is smaller than

the constant value (AT) which is determined by the manufacturer is checked, if the compressor (7) is not operating or the difference between the freezer compartment (1) temperature (TFR) and the minimum freezer compartment (1) temperature value (TFR. min) is larger than the constant value (AT) which is determined by the manufacturer, the procedure returns back to the first step (100).

The present invention makes it possible to cool the fresh food compartment (2) without requiring the fresh food compartment (2) temperature to attain the temperature upper limit value (TFCmax) as determined by the manufacturer and thereby providing the oscillating temperature values determined by the manufacturer to change within the range of optimal temprature values at which the fresh food compartment will operate more efficiently.