WO2005093346A1

WO2005093346A1 - A cooling device and a control method thereof

Info

Publication number: WO2005093346A1
Application number: PCT/IB2005/051028
Authority: WO
Inventors: Turgay Ercan; Adnan Guler; Ilker Takil
Original assignee: Arcelik Anonim Sirketi
Priority date: 2004-03-25
Filing date: 2005-03-24
Publication date: 2005-10-06
Also published as: EP1730456A1; RU2360190C2; TR200605213T1; RU2006137570A

Abstract

Heater (7) inside the freshfood compartment (2) is operated partially during the quick-freeze process, ensuring that the electric consumption cost of the user is reduced and also, that the foods inside the freshfood compartment (2) do not spoil as a consequence of overheating.

Description

Description A COOLING DEVICE AND A CONTROL METHOD THEREOF

[001] This invention relates to a cooling device and a control method thereof, wherein quick-freeze process is performed more effectively.

[002] Cooling devices comprise a freshfood compartment to preserve foods and beverages and a freezing compartment for frozen foods. The fact that the foods placed in the freezing compartment freeze in a very short period of time and that, consequently, the temperatures of the foods placed into the freshfood compartment and of frozen foods are kept at a constant level without much fluctuation during the mentioned freezing ensure that foods may be preserved for a longer period of time. In cooling devices, there is a "quick-freeze" function in order to perform the freezing process quickly when new food packages are placed into the said freezing compartment. If the quick-freeze function in the cooling device is activated, the compressor is operated constantly so as to ensure that the new food packages inside the freezing compartment are frozen quickly. In cooling devices wherein the refrigeration process is performed by means of serial evaporatorslocated in the freshfood and freezing compartments, there is a corresponding constant flow of low temperature refrigerant into the evaporator of the freshfood compartment in the course of the quick- freeze process. This, in turn, results in a decrease of the temperature of the freshfood compartment below the freezing temperature of the foods. In order to prevent the foods inside the freshfood compartment from freezing, a heater is placed into the said freshfood compartment. As the quick-freeze process starts, by activating the heater, an undesirable decrease in the temperature of the freshfood compartment is avoided. However, the use of the mentioned heater causes an increase in the energy consumption of the cooling device. Thus, various control methods are developed in order to decrease the energy consumption of the heater.

[003] In the British Patent Application no. GB 1494217, a description is given of an application wherein the heater inside the freshfood compartment operates at full capacity during the quick-freeze process, whereas during the regular operation period, it operates at half capacity by means of a diode.

[004] In the European Patent Document no. EP0045728, a description is given of an application wherein the compressor is turned off if the temperature of the freshfood compartment falls below 0°C during the quick-freeze process.

[005] The aim of the present invention is the realization of a cooling device and a control method thereof wherein the heater inside the freshfood compartment is controlled in order to prevent the freshfood compartment from being heated in an uncontrolled manner and to decrease the electric consumption cost of the user during the quick- freeze process. [006] The cooling device and the control method thereof designed to fulfill the objectives of the present invention are illustrated in the attached figures where: [007] Fig.l - is a schematic view of a cooling device.

[008] Fig.2 - is a flowchart of a control method of a cooling device.

[009] Fig.3 - is a circuit diagram illustrating the connection structure of a thermostat, a compressor and a heater. [010] Parts shown in figures are numbered as follows: 1. Cooling device 2. Freshfood compartment 3. Freezing compartment 4. Compressor 5. Freshfood compartment evaporator 6. Freezing compartment evaporator 7. Heater 8. Thermostat 9. Adjusting button 10. Quick-freeze switch 11. Heater switch 12. Compressor switch

[011] The cooling device (1) comprises a freshfood compartment (2) wherein foods and beverages are preserved, a freezing compartment (3) used to preserve the foods frozen, a compressor (4) whereby the refrigeration cycle is accomplished, a freshfood compartment evaporator (5) ensuring that the internal volume of the freshfood compartment (2) is cooled by absorbing thermal energy, a freezing compartment evaporator (6) that is in series with the freshfood compartment evaporator (5), a heater (7) inside the freshfood compartment (2), an adjusting switch (9) enabling the user to chose the quick-freeze state or the operation state that changes between the maximum and minimum values, corresponding to different amounts of refrigeration, and ac cordingly determining the activation and/or deactivation temperatures of the compressor (4) and, a thermostat (8) sensing the temperature of the freshfood compartment (2) so that the compressor (4) is turned on and off with respect to the position of the adjusting button (9), if the adjusting button (9) is set to the quick-freeze state, activating the heater (7) at a temperature lower than the deactivation temperature of the compressor (4) at maximum refrigeration state and higher than the deactivation temperature of the compressor (4) at quick-freeze state and, keeping the heater (7) activated until the quick-freeze process is completed or until a temperature higher than the deactivation temperature of the compressor (4) at maximum state is reached. [012] If the adjusting button (9) is set to the quick-freeze state, the compressor (4) is turned on. The heater (7) is not activated since the freshfood compartment (2) cannot reach low temperatures immediately when the compressor (4) is first turned on. After the temperature of the freshfood compartment (2) drops a few degrees, the thermostat (8) activates the heater (7). The heater (7) is kept activated until the quick-freeze process is completed or the temperature of the freshfood compartment (2) increases up to a limiting value which is set in order to prevent overheating.

[013] To be able to describe the control method of a cooling device (1) subject to the present invention, the following symbols are utilized:

[014] TI : is the temperature at which the thermostat (8) deactivates the compressor (4), when the adjusting button (9) is at maximum state,

[015] T2 : is the temperature at which the thermostat (8) deactivates the compressor (4), when the adjusting button (9) is at quick-freeze state,

[016] T3 : is the temperature at which the thermostat (8) activates the heater (7),

[017] T4 : is the temperature at which the thermostat (8) deactivates the heater (7),

[018] T5 ; is the temperature at which the thermostat (8) activates the compressor (4).

[019] The thermostat (8) is connected in series with the power supply on one side and the compressor (4) and heater (7) on the other side. Electrically, the compressor (4) and the heater (7) are connected in parallel. The thermostat (8) comprises a heater switch (11) connected in series with the heater (7), made of temperature-sensitive material, which closes the circuit when the temperature of the freshfood compartment (2) reaches the activation temperature (T3) of the heater (7) and opens the circuit when the temperature of the freshfood compartment (2) reaches the deactivation temperature (T4) of the heater (7), a compressor switch (12) connected in series with the compressor (4), made of temperature-sensitive material, which closes the circuit when the temperature of the freshfood compartment (2) reaches the activation temperature (T5) of the compressor (4) and opens the circuit when the temperature of the freshfood compartment (2) reaches the deactivation temperature (TI or T2) of the compressor (4), and a quick-freeze switch (10) positioned serially before the heater switch (11), which closes the circuit if the adjusting button (9) is set to the quick-freeze state and prevents the heater (7) from activating by opening the circuit if the quick-freeze state is turned off.

[020] The thermostat (8) activates the compressor (4) and the heater (7) with respect to the states set by the adjusting button (9) considering the temperatures (TI T2, T3, T4, T5). The relation between the temperatures is T2 < T3 < TI < T4 < T5. Since the temperature (T3) where the thermostat (8) activates the heater (7) is lower than the deactivation temperature (TI) of the compressor (4) when the adjusting button is set to the maximum state, the heater is never activated during the normal operation state. [021] In the cooling device (1), the quick-freeze process is carried out as follows:

[022] - Set the adjusting button (9) to the quick-freeze state (101),

[023] - Check whether the compressor (4) is operating (102),

[024] - If the compressor (4) is operating, go to the step (105) wherein the temperature of the freshfood compartment (2) is sensed and compared with the temperature (T3) at which the thermostat (8) activates the heater (7), [025] - If the compressor (4) is not operating, sense the temperature of the freshfood compartment (2) and compare it with the temperature (T5) at which the thermostat (8) activates the compressor (4) (103), [026] - If the temperature of the freshfood compartment (2) is lower than the temperature (T5) at which the thermostat (8) activates the compressor (4), go back to step (102) wherein it is checked whether the compressor (4) is operating, [027] - If the temperature of the freshfood compartment (2) is higher than the temperature (T5) at which the thermostat (8) activates the compressor (4), turn on the compressor (4) (104), [028] - Sense the temperature of the freshfood compartment (2) and compare it with the temperature (T3) at which the thermostat (8) activates the heater (7) (105), [029] - If the temperature of the freshfood compartment (2) is higher than the temperature (T3) at which the thermostat (8) activates the heater (7), continue to operate the compressor (4) (104), [030] - If the temperature of the freshfood compartment (2) is lower than the temperature (T3) at which the thermostat (8) activates the heater (7), turn on the heater (7) (106), [031] - Sense the temperature of the freshfood compartment (2) and compare it with the temperature (T4) at which the thermostat (8) deactivates the heater (7) (107), [032] - If the temperature of the freshfood compartment (2) is higher than the temperature (T4) at which the thermostat (8) deactivates the heater (7), deactivate the heater (7) (108), [033] - Continue to operate the compressor (4) (104),

[034] - If the temperature of the freshfood compartment (2) is lower than the temperature (T4) at which the thermostat (8) deactivates the heater (7), sense the temperature of the freshfood compartment (2) and compare it with the temperature (T2) at which the thermostat (8) deactivates the compressor (4) when the adjusting button (9) is at quick- freeze state (109), [035] - If the temperature of the freshfood compartment (2) is higher than the temperature (T2) at which the thermostat (8) deactivates the compressor (4) when the adjusting button (9) is at quick-freeze state, continue to operate the compressor (4) (104), [036] - If the temperature of the freshfood compartment (2) is lower than the temperature (T2) at which the thermostat (8) deactivates the compressor (4) when the adjusting button (9) is at quick-freeze state, deactivate the compressor (4) (110),

[037] - Go back to the step (102) wherein it is checked whether the compressor (4) is operating.

[038] The quick-freeze process continues until the thermostat (8) is switched from the quick-freeze state by the user.

[039] In another embodiment of the present invention, the thermostat (8) senses the te mperature on the freshfood compartment evaporator (5). In this embodiment, the thermostat (8) controls the on / off operations of the compressor (4) and the heater (7) with respect to the temperature values that it senses on the freshfood compartment evaporator (5).

[040] In another embodiment of the present invention, in lieu of a two-switch (11 and 12) thermostat (8) controlling the on / off operations of the compressor (4) and the heater (7), two single-switch thermostats (8) are utilized. Out of the two thermostats (8), one is used to control the on / off operations of the heater (7) and the other is used to control the on / off operations of the compressor (4).

[041] The fact that the operation of the heater (7) is prevented for the entire quick-freeze process period and instead, operates only if necessary, ensures that the electric consumption cost of the user is reduced and that the foods inside the freshfood compartment (2) do not spoil as a consequence of overheating.

Claims

[0O1] A cooling device (1) comprising, a freshfood compartment (2) wherein foods and beverages are preserved; a freezing compartment (3) which is used to preserve the foods frozen; a compressor (4) whereby the refrigeration cycle is accomplished; a heater (7) inside the freshfood compartment (2) and; an adjusting switch (9) enabling the user to chose the quick-freeze state or the operation state that changes between the maximum and minimum values, corresponding to different amounts of refrigeration, and accordingly determining the activation and/or deactivation temperatures of the compressor (4); and characterized by a thermostat (8) sensing the temperature of the freshfood compartment (2) so that the compressor (4) is turned on and off with respect to the position of the adjusting button (9), if the adjusting button (9) is set to the quick-freeze state, activating the heater (7) at a temperature lower than the deactivation temperature of the compressor (4) at maximum refrigeration state and higher than the deactivation temperature of the compressor (4) at quick-freeze state and, keeping the heater (7) activated until the quick-freeze process is completed or until a temperature higher than the deactivation temperature of the compressor (4) at maximum state is reached.

[002] A cooling device (1) as described in Claim 1, characterized by a thermostat (8) which comprises, a heater switch (11) connected in series with the heater (7) which closes the circuit when the temperature of the freshfood compartment (2) reaches the activation temperature (T3) of the heater (7) and opens the circuit when the temperature of the freshfood compartment (2) reaches the deactivation temperature (T4) of the heater (7); a compressor switch (12) connected in series with the compressor (4) which closes the circuit when the temperature of the freshfood compartment (2) reaches the activation temperature (T5) of the compressor (4) and opens the circuit when the temperature of the freshfood compartment (2) reaches the deactivation temperature (TI or T2) of the compressor (4) and; a quick-freeze switch (10) positioned serially before the heater switch (11), which closes the circuit if the adjusting button (9) is set to the quick-freeze state and prevents the heater (7) from activating by opening the circuit if the quick-freeze state is turned off.

[003] A control method for a cooling device as described in Claims 1 or 2, which comprises the following steps : Set the adjusting button (9) to the quick-freeze state (101); Check whether the compressor (4) is operating (102); If the compressor (4) is operating, go to the step (105) wherein the temperature of the freshfood compartment (2) is sensed and compared with the temperature (T3) at which the thermostat (8) activates the heater (7); If the compressor (4) is not operating, sense the temperature of the freshfood compartment (2) and compare it with the temperature (T5) at which the thermostat (8) activates the compressor (4) (103); If the temperature of the freshfood compartment (2) is lower than the temperature (T5) at which the thermostat (8) activates the compressor (4), go back to the step (102) wherein it is checked whether the compressor (4) is operating; If the temperature of the freshfood compartment (2) is higher than the temperature (T5) at which the thermostat (8) activates the compressor (4), turn on the compressor (4) (104); Sense the temperature of the freshfood compartment (2) and compare it with the temperature (T3) at which the thermostat (8) activates the heater (7) (105); If the temperature of the freshfood compartment (2) is higher than the temperature (T3) at which the thermostat (8) activates the heater (7), continue to operate the compressor (4) (104); If the temperature of the freshfood compartment (2) is lower than the temperature (T3) at which the thermostat (8) activates the heater (7), turn on the heater (7) (106); Sense the temperature of the freshfood compartment (2) and compare it with the temperature (T4) at which the thermostat (8) deactivates the heater (7) (107); If the temperature of the freshfood compartment (2) is higher than the temperature (T4) at which the thermostat (8) deactivates the heater (7), deactivate the heater (7) (108); Continue to operate the compressor (4) (104); If the temperature of the freshfood compartment (2) is lower than the temperature (T4) at which the thermostat (8) deactivates the heater (7), sense the temperature of the freshfood compartment (2) and compare it with the temperature (T2) at which the thermostat (8) deactivates the compressor (4) when the adjusting button (9) is at quick-freeze state (109); If the temperature of the freshfood compartment (2) is higher than the temperature (T2) at which the thermostat (8) deactivates the compressor (4) when the adjusting button (9) is at quick-freeze state, continue to operate the compressor (4) (104); If the temperature of the freshfood compartment (2) is lower than the temperature (T2) at which the thermostat (8) deactivates the compressor (4) when the adjusting button (9) is at quick-freeze state, deactivate the compressor (4) (110); Go back to the step (102) wherein it is checked whether the compressor (4) is operating.