US20130098083A1

US20130098083A1 - Refrigerator

Info

Publication number: US20130098083A1
Application number: US13/703,402
Authority: US
Inventors: Hyunwoo Kong
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2010-07-12
Filing date: 2011-07-12
Publication date: 2013-04-25
Also published as: KR20120006287A; WO2012008724A2; WO2012008724A3

Abstract

Provided is a refrigerator. Data about operations and states of the refrigerator are accumulated in a portable memory unit detachably attached to the refrigerator. Therefore, the portable memory unit can be detached from the refrigerator and connected to a personal computer (PC) to analyze reasons of errors of the refrigerator and find out potential errors of the refrigerator. Accordingly, maintenance of the refrigerator can be easily carried out.

Description

TECHNICAL FIELD

The present disclosure relates to a refrigerator.

BACKGROUND ART

Refrigerators are home appliances for storing foods at a low temperature. For this, refrigerators include storage chambers closed by doors. In a refrigerator, air cooled by heat exchange with a refrigerant circulating in a refrigeration cycle is supplied into a storage chamber for keeping the foods placed in the storage chamber at optimal states.
Recently, consumption of large and multifunctional refrigerators have increased with the change of people's eating patterns and preference, and refrigerators having various structures and convenience devices have been introduced in the market.
Such a refrigerator includes components for the refrigeration cycle of the refrigerator, components for circulating cooling air, and a control unit for controlling the components. A control program is installed on the control unit to control operations of the components. That is, the components are operated according to the program.
In addition, sensors and switches are disposed in the refrigerator to measure and check inner states of the refrigerator. Data about operations of the sensors and switches are transmitted to the control unit and input to the program so as to optimally operate the refrigerator according to variations of environments.
If the refrigerator behaves abnormally, the control unit can detect such an abnormal state based on a signal from a detection unit including the sensors and the switches. An alarm message may be output through a display or a speaker to inform a user of the abnormal state. Then, the user may determine whether the refrigerator is defective and take action.
However, in the related art, it takes much time if a user calls a service engineer after an error signal is generated. Furthermore, since operation data transmitted to the control unit are not stored for a long time, it may be difficult to diagnose errors of the refrigerator.
That is, except for the case where an abnormal state continues or an error signal is continuously or repeatedly generated, it may be difficult to find out reasons of errors and take proper action after a certain period of time.
For this reason, wired or wireless communication technology is applied to a refrigerator to transmit error signals of the refrigerator to a remote server for analyzing the reasons of errors.
However, such a remote analysis function of the refrigerator can be used only under a wired or wireless communication environment. Moreover, a temporary abnormal behavior of the refrigerator caused not by an error but by a change of an operation condition or mode may be reported in real time to the server, and thus an unnecessary service call may be made.

DISCLOSURE OF INVENTION

Technical Problem

Embodiments provide a refrigerator including a detachable portable memory unit for accumulating data about operations and states of the refrigerator. The portable memory unit can be detached from the refrigerator and connected to a personal computer (PC) to analyze reasons of errors of the refrigerator and find out potential errors of the refrigerator for easy maintenance of the refrigerator.

Solution to Problem

In one embodiment, a refrigerator includes: a load unit including devices necessary for operation of the refrigerator; a detection unit configured to detect operations of the load unit and states of the refrigerator; a control unit configured to control operations of the load unit, the control unit including a memory unit to receive data about operations and states of the refrigerator from the detection unit; and a history data memory unit including a detachable portable memory unit connected to the control unit, wherein data input to the memory unit of the control unit are periodically copied to the portable memory unit so as to accumulate data about operations and states of the refrigerator.

Advantageous Effects of Invention

According to the embodiments, a program is installed on the memory unit of the control unit for controlling operations of the load unit, and data about operational states of the refrigerator are transmitted from the detection unit to the memory unit and then accumulated to the portable memory unit.
Therefore, data about operations of the refrigerator can be accumulated in the portable memory unit for a certain period of time, and thus errors of the refrigerator can be diagnosed using a program and reference data of a personal computer (PC) or a server.
Particularly, although the refrigerator is diagnosed after a certain period of time from an error of the refrigerator, the reason of the error may be reliably diagnosed using accumulated data. In addition, since the refrigerator is diagnosed using accumulated data, information about user's pattern of using the refrigerator and changes of operation environments can also be checked.
In addition, since the portable memory unit is detachably provided to the refrigerator, data of the portable memory unit can be easily read using a PC, and the portable memory unit can be easily carried. Furthermore, when the refrigerator is check, errors of the refrigerator may be easily diagnosed by only checking data accumulated in the portable memory unit.
Furthermore, the portable memory unit can be connected to a PC to transmit data accumulated in the portable memory unit to a server through the internet. The data transmitted to the server can be used as raw data for analyzing the performance of the refrigerator. Therefore, the performance the refrigerator can be effectively maintained, and the refrigerator can be easily repaired.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view illustrating a refrigerator according to an embodiment.

FIG. 2 is a block diagram illustrating the refrigerator.

FIG. 3 is a block diagram illustrating a refrigerator according to another embodiment.

FIG. 4 is a view illustrating a history data memory unit provided at a door hinge according to an embodiment.

FIG. 5 is a view illustrating the history data memory unit provided at a display according to an embodiment.

FIG. 6 is a view illustrating the history data memory unit provided at a door deco according to an embodiment.

FIG. 7 is a view for explaining how an error of the refrigerator is diagnosed according to an embodiment.

FIG. 8 is a flowchart for explaining how an error of the refrigerator is diagnosed according to the embodiment.

MODE FOR THE INVENTION

Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. The spirit and scope of the present disclosure, however, shall not be construed as being limited to embodiments provided herein. Rather, it will be apparent that other embodiments that fall within the spirit and scope of the present disclosure may easily be derived through adding, modifying, and deleting elements herein.
Although a side-by-side-type refrigerator is exemplified in the following embodiments for clarity and convenience of explanation, the inventive concept of the present disclosure can be applied to any other refrigerator while varying the position of a control unit.
FIG. 1 is a perspective view illustrating a refrigerator 1 according to an embodiment.
Referring to FIG. 1, the refrigerator 1 of the current embodiment includes a cabinet 100 in which a storage chamber is formed, and doors 200 used to close and open the storage chamber.
The inside of the cabinet 100 is divided into left and right parts by a barrier wall. For example, a freezer compartment is formed in the left part of the cabinet 100, and a refrigerator compartment is formed in the right part of the cabinet 100. A plurality of racks and drawers are disposed in the freezer compartment and the refrigerator compartment to store foods.
The doors 200 include a freezer compartment door 210 and a refrigerator compartment door 220 for closing and opening the freezer compartment and the refrigerator compartment. The freezer compartment door 210 and the refrigerator compartment door 220 are rotatably installed on the cabinet 100 by using door hinges 110 so that the refrigerator compartment and the freezer compartment can be opened and closed by rotating the doors 210 and 220.
A home bar 222 may be provided at the refrigerator compartment door 220. The home bar 222 forms a storage space that can be opened and closed from the outside of the refrigerator compartment door 220. A dispenser 212 may be provided at the freezer compartment door 210. Purified water or ice made by an ice maker (not shown) may be taken from the outside of the freezer compartment door 210 through the dispenser 212.
A display 230 is provided above the dispenser 212. The display 230 is used to display operational states of the refrigerator 1. The display 230 may be a touch-screen display so that a user can input operational conditions by touching the display 230.
Although not shown in detail, the refrigerator 1 includes a load unit 120 (refer to FIG. 2 or 3) including a plurality of components for operation of the refrigerator 1, and a control unit 300 for controlling the load unit 120.
For example, the load unit 120 may include a compressor, a condenser, an evaporator, and an expansion unit for the refrigeration cycle of the refrigerator 1. In addition, the load unit 120 may include a fan motor and a damper for blowing cooling air, illumination units, and electric components of the ice maker and the dispenser 212.
The refrigerator 1 may include a detection unit 130 (refer to FIG. 2 or 3) such as sensors and switches. For example, the refrigerator 1 may include temperature sensors and door switches.
The control unit 300 is disposed on the topside of the cabinet 100. The control unit 300 includes a printed circuit board (PCB) disposed on the topside of the cabinet 100. The control unit 300 is roofed with a cover.
FIG. 2 is a block diagram illustrating the refrigerator 1.
Referring to FIG. 2, the refrigerator 1 of the current embodiment includes the control unit 300. The control unit 300 controls operations of the refrigerator 1. The load unit 120, the detection unit 130, and an output unit (described later) 140 may be connected to the control unit 300. The control unit 300 includes a memory unit 310 and a history date memory unit 400. The memory unit 310 includes a program installed for operating the refrigerator 1. The history date memory unit 400 includes a portable memory unit 410 for storing data accumulated while the program is executed.
In detail, the refrigerator 1 includes the load unit 120. The load unit 120 is operated according to the program installed on the memory unit 310 of the control unit 300. Even when the refrigerator 1 is powered on or off, the load unit 120 is controlled according to the program. Data about operations and states of the load unit 120 may be temporarily stored in the memory unit 310 of the control unit 300.
The refrigerator 1 includes the detection unit 130. The detection unit 130 is connected to the memory unit 310 of the control unit 300 to transmit data detected by the detection unit 130 to the memory unit 310.
Data of the load unit 120 and the detection unit 130 transmitted to the memory unit 310 and stored in the memory unit 310 are immediately transferred to the portable memory unit 410 if an abnormal state is detected. That is, data of the load unit 120 and the detection unit 130 are not retained in the memory unit 310 but are transferred to the portable memory unit 410 at intervals.
Therefore, data of the load unit 120 and the detection unit 130 are input to the memory unit 310 at intervals, and the program is executed using the input data to operate the load unit 120. In this way, the refrigerator 1 may be operated. At the same time, data of the load unit 120 and the detection unit 130 input to the memory unit 310 are coped to the portable memory unit 410 as backup data. The backup data may be deleted later or overwritten by new data of the load unit 120 and the detection unit 130.
The history date memory unit 400 is disposed at a side of the memory unit 310 to receive data from the memory unit 310 as backup data. The history date memory unit 400 includes the portable memory unit 410 for storing data received from the memory unit 310. In addition, the history date memory unit 400 may further include a capacitor to maintain supply of power to the portable memory unit 410.
The portable memory unit 410 storing backup data input from the memory unit 310 may be a detachable storage medium such as a secure digital (SD) card.
The portable memory unit 410 may be attached to the history date memory unit 400 to accumulate data input from the memory unit 310. When data are stored in the portable memory unit 410, identification codes may be assigned to the data according to time so that time information can be obtained when reading the data later.
Since the capacity of the portable memory unit 410 is limited, the portable memory unit 410 may be fully filled with data after a certain period of time. Therefore, so as to properly check historical operation states of the refrigerator 1, it may be necessary to transmit data stored in the portable memory unit 410 to another device such as a personal computer (PC) at predetermined intervals according to the capacity and kind of the portable memory unit 410 and the amount and storing frequency of data generating from the load unit 120 and the detection unit 130.
For example, if the amount of data generating from the load unit 120 and the detection unit 130 is considered, data generated for six months may correspond to the capacity of a 2-GB SD card. That is, data may be transmitted from a 2-GB SD card to another device every six months.
If the 2-GB SD card is fully filled with data after six months, new data are stored in the 2-GB SD card while deleting the oldest entries of the data from the 2-GB SD card. That is, even after data are transmitted from the portable memory unit 410 to a PC, data within six months may remain in the portable memory unit 410. Therefore, when diagnosing the refrigerator 1 using data stored in the portable memory unit 410, data search is possible from the latest entries of the data.
The refrigerator 1 includes the output unit 140. The output unit 140 informs of an abnormal behavior of the refrigerator 1 and a reset time of the portable memory unit 410. The output unit 140 is connected to the control unit 300. The output unit 140 may be the display 230. If necessary, the output unit 140 may include an external display or a speaker.
The output unit 140 is connected to the control unit 300 to output a sound or message if data indicating an error are input to the memory unit 310. In addition, if the amount of data stored in the portable memory unit 410 approaches the capacity of the portable memory unit 410, the output unit 140 may inform of this situation.
Therefore, if there is a serious error of the refrigerator 1, a user may be informed of the error and take action. In addition, if a sufficient storage space does not remain in the portable memory unit 410, a user may be informed of that.
Data may be stored in the portable memory unit 410 in file allocation table (FAT) format so that the data can be easily processed in a PC 2 (refer to FIG. 7). For example, data stored in the portable memory unit 410 may be analyzed using a diagnosis program installed on the PC 2 to find out an erroneous state. Data can be transmitted to a remote server 3 from the PC 2.
As described above, the history date memory unit 400 may includes a capacitor. When the history date memory unit 400 is powered off, a file system of the portable memory unit 410 can be shut down by using power supplied from the capacitor.
For example, if there is a blackout or power is not supplied due to other reasons while the refrigerator 1 is operated, the file system of data stored in the portable memory unit 410 can be shut down by using power supplied from the capacitor.
A control unit having a structure different from that of the control unit 300 of the previous embodiment may be used. Hereinafter, another embodiment will be described with reference to the accompanying drawing.
In a refrigerator of the other embodiment, a history data memory unit is spaced apart from a control unit.
The refrigerator of the other embodiment has the same structure as the refrigerator of the previous embodiment except for the structure of the control unit. Thus, the same elements as those of the previous embodiment will be denoted by the same reference numerals, and detailed descriptions thereof will not be repeated.
FIG. 3 is a block diagram illustrating a refrigerator 1 according to another embodiment.
Referring to FIG. 3, the refrigerator 1 of the other embodiment includes a control unit 300. The control unit 300 controls operations of the refrigerator 1. A load unit 120, a detection unit 130, and an output unit 140 are connected to the control unit 300. The control unit 300 includes a memory unit 310 on which a program is installed for operating the refrigerator 1. The control unit 300 is connected to a history data memory unit 500. The history data memory unit 500 includes a portable memory unit 510 for storing data of the memory unit 310.
In detail, state information of the refrigerator 1 may be transmitted from the load unit 120 and the detection unit 130 to the memory unit 310 of the control unit 300. The load unit 120 is operated according to the program installed on the memory unit 310 of the control unit 300 for refrigeration of the refrigerator 1.
The control unit 300 may further include the output unit 140 for generating an alarm message if data indicating an error are input to the memory unit 310. In addition, if the amount of data stored in the portable memory unit 510 becomes greater than a reference capacity, the output unit 140 generates a corresponding message. Then, the portable memory unit 510 may be replaced.
The history data memory unit 500 is spaced apart from the control unit 300. The history data memory unit 500 may be connected to the control unit 300 by a wired or wireless manner.
State data of the refrigerator 1 are input to the history data memory unit 500 through the memory unit 310 and are stored in the history data memory unit 500. Data may be stored in the history data memory unit 500 in FAT format so that the data can be easily processed in the PC 2 (refer to FIG. 7). The history data memory unit 500 may further include a capacitor. The capacitor may be used to shut down a file system of the portable memory unit 510.
The history data memory unit 500 may be disposed at a position where a user can easily detach the portable memory unit 510. This will be described below in detailed with reference to the accompanying drawings.
FIG. 4 is a view illustrating the history data storage unit 500 provided at one of the door hinges 110 according to an embodiment.
Referring to FIG. 4, the door hinge 110 is provided at a corner formed by the front and lateral ends of the topside of the cabinet 100. The door hinge 110 may include: a hinge plate 112 connecting the cabinet 100 and the door 200 (refer to the freezer compartment door 210 or the refrigerator compartment door 220 of FIG. 1); and a hinge cover 114 enclosing the hinge plate 112.
The history date memory unit 500 is disposed in the hinge cover 114. The hinge cover 114 includes a slot 116 as an entrance for the portable memory unit 510. Therefore, a user can attach the portable memory unit 510 to the history data memory unit 500 through the slot 116 and detach the portable memory unit 510 from the history data memory unit 500 through the slot 116.
The history data memory unit 500 may be connected to the control unit 300 disposed on the topside of the cabinet 100 through a wire. If an electric component is disposed in the door 200, the wire may extend from the control unit 300 to the inside of the door 200 through the hinge plate 112.
FIG. 5 is a view illustrating the history data storage unit 500 provided at the display 230 according to an embodiment.
Referring to FIG. 5, the display 230 may be provided at a side of the door 200 (refer to the freezer compartment door 210 or the refrigerator compartment door 220 of FIG. 1). The history data memory unit 500 may be disposed at the display 230 or a side close to the display 230.
For example, the history data memory unit 500 may be disposed at the display 230 or an inner side of the door 200 close to the display 230. A slot 232 is formed through the display 230 at a position corresponding to the position of the history data memory unit 500 or through a side of the door 200 close to the display 230. The portable memory unit 510 can be inserted through the slot 232.
Therefore, a user can attach or detach the portable memory unit 510 at the easily-accessible display 230. If necessary, an additional cover may be provided at the display 230 or the door 200 to cover the slot 232.
A wire may extend from the control unit 300 to the door 200 where the display 230 is mounted, and then the wire may be connected to the history data memory unit 500. The dispenser 212 may be disposed under the display 230.
FIG. 6 is a view illustrating the history data storage unit 500 provided at a door deco 240 according to an embodiment.
Referring to FIG. 6, the door 200 (refer to the freezer compartment door 210 or the refrigerator compartment door 220 of FIG. 1) of the refrigerator 1 may include: a door panel 250 forming the front side of the door 200; and the door deco 240 formed around the door 200.
In detail, the door panel 250 disposed on the front side of the door 200 may be formed of strengthened glass, plastic, or an iron sheet. A door liner (not shown) may be disposed on the rear side of the door 200. The inside of the door 200 may be filled with an insulator.
The door deco 240 may be formed around the door 200 by using plastic or an aluminum material. If the door panel 250 is formed of strengthened glass, the door deco 240 may receive and fix edges of the door panel 250.
The history data memory unit 500 may be disposed in the door deco 240. The history data memory unit 500 may be disposed at the rear side of the door deco 240, and a slot 242 may be formed in a side of the door deco 240 at a position corresponding to the history data memory unit 500 so that the portable memory unit 510 can be inserted through the slot 242. The slot 242 may be formed in the topside or bottom side of the door 200 that is not easily exposed to the outside of the refrigerator 1.
Hereinafter, operations of the refrigerator 1 will be described according to an embodiment with reference to the accompanying drawings.
FIG. 7 is a view for illustrating how an error of the refrigerator 1 is diagnosed according to an embodiment. FIG. 8 is a flowchart for explaining how an error of the refrigerator 1 is diagnosed according to the embodiment.
Referring to FIGS. 7 and 8, if the refrigerator 1 is powered on, the control unit 300 controls operations of the refrigerator 1. The load unit 120 of the refrigerator 1 is operated according to the program installed on the memory unit 310. [S 100]
When the load unit 120 is operated, data about operations of the load unit 120 are fed back to the memory unit 310. That is, the inside state of the refrigerator 1 may be varied according to operations of the load unit 120, and the detection unit 130 may detect the variations of the inside states of the refrigerator 1 and transmit the detected data to the memory unit 310. [S200]
The operations of the load unit 120 are controlled by the program installed on the memory unit 310 based on the data transmitted from the detection unit 130 and operation conditions of the load unit 120.
The data input to the memory unit 310 are transferred to the portable memory unit 410 at predetermined intervals and are accumulated in the portable memory unit 410. [S300]
Since the capacity of the portable memory unit 410 is limited, if data equal to or greater than a preset amount are accumulated in the portable memory unit 410, the output unit 140 generates a message to request a data backup of the portable memory unit 410.
In spite of the message, the portable memory unit 410 may be further used. In this case, new data are stored in the portable memory unit 410 by overwriting old data with the new data. Therefore, the portable memory unit 410 can store data from the latest data for a certain period of time.
If data input to the memory unit 310 contain information about a state requiring an immediate action or an abnormal behavior of the refrigerator 1, a corresponding message may be output by the output unit 140. [S310]
If it is determined that the refrigerator 1 behaves abnormally or the amount of data accumulated in the portable memory unit 410 is greater than a preset amount, the portable memory unit 410 may be detached and then connected to the PC 2. [S400]
Since data are stored in the portable memory unit 410 in FAT format readable by the PC 2, if an error diagnosis program is installed on the PC 2, whether the refrigerator 1 behaves abnormally can be determined by using the error diagnosis program.
At this time, data stored in the portable memory unit 410 can be read in the order of time. Then, the data can be compared with reference data stored in the PC 2 for determining whether the refrigerator 1 behaves abnormally.
Information about time and interval of errors of the refrigerator 1 can be checked using the accumulated data stored in the portable memory unit 410. In addition, since a large amount of data about operations of the refrigerator 1 can be checked, it can be determined whether errors are caused by a user's habit or actual defect of the load unit 120. [S500]
If an error diagnosis program is not installed on the PC 2 or reference data are not stored in the PC 2, a user can access the remote server 3 through the internet from the PC 2 to which the portable memory unit 410 is connected.
Since an error diagnosis program is installed on the remote server 3 and reference data are stored in the remote server 3, diagnosis results of the refrigerator 1 may be checked on a web site provided by the remote server 3.
In addition, data stored in the portable memory unit 410 may be used to analyze user's habits of using the refrigerator 1. Particularly, if the portable memory unit 410 is periodically connected to the PC 2 to store operational data of the refrigerator 1 from the portable memory unit 410 to the PC 2, operational data of the refrigerator 1 can be accumulated for a long time, and thus errors of the refrigerator 1 may be predicted based on the accumulated operational data. In addition, if operational data of the refrigerator 1 are input to the remote server 3 through the internet, reasons of errors of the refrigerator 1 can be analyzed and operational characteristics of the load unit 120 can be monitored by using the data.
In a state where the portable memory unit 410 is detached from the refrigerator 1, the refrigerator 1 is operated by the program installed on the memory unit 310 and operational data are stored in the memory unit 310. Then, the portable memory unit 410 is attached again to the history date memory unit 400, the operational data are stored in the portable memory unit 410.

Industrial Applicability

According to the embodiments, operational data can be stored in the refrigerator, and the refrigerator includes a portable memory unit for storing the operational data. Therefore, abnormal behaviors of the refrigerator can be diagnosed, and operational data of the refrigerator can be accumulated in a database. As a result, the refrigerator can have high industrial applicability because maintenance of the refrigerator is easy.

Claims

1. A refrigerator comprising:

a load unit comprising devices necessary for operation of the refrigerator;

a detection unit configured to detect operations of the load unit and states of the refrigerator;

a control unit configured to control operations of the load unit, the control unit comprising a memory unit to receive data about operations and states of the refrigerator from the detection unit; and

a history data memory unit comprising a detachable portable memory unit connected to the control unit,

wherein data input to the memory unit of the control unit are periodically copied to the portable memory unit so as to accumulate data about operations and states of the refrigerator.

2. The refrigerator according to claim 1, wherein the history data memory unit and the control unit are provided as one part.

3. The refrigerator according to claim 1, wherein the history data memory unit is disposed at a side of the refrigerator spaced apart from the control unit.

4. The refrigerator according to claim 3, wherein the history data memory unit is disposed at a side of a hinge to which a shaft of a door of the refrigerator is coupled.

5. The refrigerator according to claim 3, wherein the history data memory unit is disposed at a door deco formed around a door of the refrigerator.

6. The refrigerator according to claim 3, wherein the history data memory unit is disposed at a side of a display that is disposed on a door of the refrigerator to display operational states of the refrigerator.

7. The refrigerator according to claim 1, wherein the portable memory unit is a secure digital (SD) card.

8. The refrigerator according to claim 1, wherein the history data memory unit further comprises a capacitor configured to supply power for shutting down a file system of the portable memory unit.

9. The refrigerator according to claim 1, further comprising an output unit configured to report a backup period of the portable memory unit.

10. The refrigerator according to claim 9, wherein the output unit is a display disposed on a door of the refrigerator to display operational states of the refrigerator.

11. The refrigerator according to claim 1, wherein data about states of the refrigerator and components of the refrigerator are temporarily stored in the memory unit until the data are backed up to the portable memory unit.

12. The refrigerator according to claim 1, wherein the portable memory unit accumulates data about states of the refrigerator and components of the refrigerator, and if the data accumulated in the portable memory unit reaches a preset amount, new data are stored in the portable memory unit while deleting the oldest entries of the accumulated data.

13. The refrigerator according to claim 1, wherein the portable memory unit accumulates data about states of the refrigerator and components of the refrigerator, and then the portable memory unit is detached from the refrigerator and connected to a personal computer (PC) on which an error diagnosis program is installed, so as to diagnose whether the refrigerator behaves abnormally.

14. The refrigerator according to claim 1, wherein the portable memory unit accumulates data about states of the refrigerator and components of the refrigerator, and then the portable memory unit is detached from the refrigerator and connected to a personal computer (PC) so as to transmit the data to a server through the internet for diagnosing whether the refrigerator behaves abnormally.