# Patent

## Title
Water tank and refrigerator having the same

## Abstract

Disclosed are a water tank and a refrigerator having the same. The water tank includes a tank main body provided with a water storage space formed therein and a discharge hole; a tank cover connected to the tank main body for opening and closing the water storage space; a valve movably installed in the tank main body for opening and closing the discharge hole; and a valve driving unit moving the valve using magnetic force so as to cause the valve to open and close the discharge hole. The water tank is opened and closed by the magnetic force of magnets and the restoring force of elastic members, and thus it is possible to prevent water stored in the water tank from leaking out in a process of attaching or detaching the water tank to or from the rear surface of a door or a refrigerator.

## Background
This application claims the benefit of Korean Patent Application No. 10-2006-0057056, filed Jun. 23, 2006, which is hereby incorporated by reference as if fully set forth herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a water tank and a refrigerator having the same, and more particularly, to a water tank for supplying water, temporarily stored therein, to an ice maker without leakage of the water, and a refrigerator having the same.
2. Discussion of the Related Art
Generally, refrigerators are electric appliances for keeping foods in a fresh state by freezing or cooling the foods, and usually include a freezing chamber and a refrigerating chamber. Further, an ice maker for making ice is provided in the freezing chamber.
FIG. 8 is a front view illustrating the internal structure of a conventional refrigerator, FIG. 9 is an exploded perspective view of a water tank provided in the refrigerator of FIG. 8, and FIG. 10 is a longitudinal sectional view of the water tank in a state in which the water tank is installed on a door of the refrigerator of FIG. 8.
As shown in FIGS. 8 to 10, a freezing chamber 11 and a refrigerating chamber 13 are provided in a main body 10 of a conventional refrigerator, and a freezing chamber door 11a and a refrigerating chamber door 13a are rotatably installed on the main body 10. The freezing chamber door 11a and the refrigerating chamber door 13a serve to selectively open and close the freezing chamber 11 and the refrigerating chamber 13, respectively.
A plurality of door baskets 14 for receiving foods are detachably installed on the rear surfaces of the freezing chamber door 11a and the refrigerating chamber door 13a, and home bars 15 and 16, through which ice and beverages can taken into and out of the refrigerator without opening the freezing chamber door 11a and the refrigerating chamber door 13a, are respectively provided in the freezing chamber door 11a and the refrigerating chamber door 13a. 
First and second ice maker housings 17 and 19 are provided on the freezing chamber door 11a at a designated position above the home bar 15, and an ice tray (not shown) for making ice is installed in the first ice maker housing 17. An ice bank (not shown) for taking the ice, made by the ice tray, out of the refrigerator through the home bar 15 is installed in the second ice maker housing 19.
A mounting space is formed between any one of the door baskets 14, installed on the rear surface of the freezing chamber door 11a, and the first ice maker housing 17, and a water tank 21 is detachably installed in the mounting space. The water tank 21 stores water, which will be supplied to the ice tray. As shown in FIG. 9, the water tank 21 includes a tank main body 22, a tank cover 23, a supply hole cover 24, and a valve 25.
The tank main body 22 has a polyhedral shape, the upper portion of which is opened, and a water storage space 22s for storing a designated amount of water is provided in the tank main body 22. A support protrusion 22a is provided on the inner surface of the edge of the tank main body 22, and a knob part 22b, which is held by user's hand so as to attach and detach the water tank 21 to and from the mounting space, is provided on one side of the lower surface of the tank main body 22.
A guide groove 22c for guiding the water tank 21 is formed in the lower surface of the tank main body 22 by upwardly indenting a part of the lower surface of the tank main body 22, and a guide rib 17a provided on the upper surface of the first ice maker housing 17 is inserted into the guide groove 22c. 
The tank cover 23 is connected to the upper portion of the tank main body 22 so as to selectively open and close the water storage space 22s, and the edge of the lower surface of the tank cover 23 is supported by the upper surface of the support protrusion 22a. A supply hole 23h for supplying water from an external water source to the water storage space 22c is formed through a designated position of the tank cover 23, and a packing groove 23a surrounding the supply hole 23h is formed in the upper surface of the tank cover 23.
A receipt stage 23b, on which the supply hole cover 24 is laid under the condition that the supply hole cover 24 closes the supply hole 23h of the tank cover 23, is formed on the upper surface of the tank cover 23. The receipt stage 23b is obtained by stepping a part of the tank cover 23 including the supply hole 23h and the packing groove 23a. 
A knob groove 23c, into which a user's hand is inserted, for rotating the supply hole cover 24 against the tank cover 23 is formed in the upper surface of the tank cover 23, and a contacting protrusion 24a and a packing protrusion 24b are provided on the lower surface of the supply hole cover 24. Under the condition that the supply hole cover 24 closes the supply hole 23h of the tank cover 23, the outer circumferential surface of the contacting protrusion 24a contacts the inner surface of the supply hole 23h, and the packing protrusion 24b is inserted into the packing groove 23a. 
With reference to FIG. 10, a discharge hole 22h for supplying the water stored in the water storage space 22 to the ice tray is formed through a designated position of the lower surface of the tank main body 22. The discharge hole 22h is connected to a water supply hole 17h formed through the upper surface of the first ice maker housing 17 under the condition that the water tank 21 is installed in the above mounting space, and an insertion rib 22r is provided on the lower surface of the tank main body 22 corresponding to the circumference of the discharge hole 22h. 
The valve 25 includes a valve bracket 26, a valve main body 27, a packing ring 28a, and a first elastic member 29. The valve bracket 26 is provided along the circumference of the discharge hole 22h of the tank main body 22, and a water supply hole 26h for substantially supplying the water stored in the water storage space 22s to the ice tray therethrough is formed through the valve bracket 26.
A receipt groove 26a is formed in a designated position of the upper surface of the valve bracket 26 adjacent to the water supply hole 26h, and the outer circumferential surface of the packing ring 28a is laid on the receipt groove 26a. 
An insertion groove 26b, into which the insertion rib 22r of the tank main body 22 is inserted, is formed in the upper surface of the valve bracket 26, and a fixing hook 26c, which is caught by the bottom surface of the tank main body 22 under the condition that the insertion rib 22r is inserted into the insertion groove 26b, is provided on the upper surface of the valve bracket 26 inside the insertion groove 26b. 
The valve main body 27 passes through the water supply hole 26h of the valve bracket 26, and is vertically movable. When the water tank 21 is installed in the mounting space, the valve main body 27 moves upwardly by means of a driving protrusion (not shown) provided on the upper surface of the first ice maker housing 17, and thus opens the water supply hole 26h of the valve bracket 26.
An insertion groove 27a, into which the inner circumferential surface of the packing ring 28a is inserted, is formed in the upper end of the valve main body 27, and a flange part 27f, the upper surface of which supports one end of the first elastic member 29, is provided on the lower end of the valve main body 27. A water supply hole 27h is formed through a position of the flange part 27f corresponding to the water supply hole 26h of the valve bracket 26.
A packing member 28b is provided between the insertion rib 22r of the tank main body 22 and the insertion groove 26b of the valve bracket 26, and both ends of the first elastic member 29 are respectively supported by the lower surface of the valve bracket 26 and the upper surface of the flange part 27f of the valve main body 27.
The above-described conventional water tank and the refrigerator having the same, have several problems, as described below.
The valve main body 27 moves upwardly by means of the driving protrusion provided on the upper surface of the first ice maker housing 17 and thus opens the water supply hole 26h of the valve bracket 26. Thereby, the water stored in the water storage space 22s is supplied to the ice tray through the discharge hole 22h of the water tank 21.
Accordingly, when the valve main body 27 moves upwardly by means of the driving protrusion and thus opens the water supply hole 26h of the valve bracket 26 under the condition that the water tank 21 is not completely installed in the mounting space, the water stored in the water storage space 22s may leak out through the discharge hole 22h of the water tank 21.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a water tank and a refrigerator having the same.
One object of the present invention is to provide a water tank, which prevents water stored therein from leaking out in a process of attaching or detaching the water tank to or from the rear surface of a door of a refrigerator, and a refrigerator having the water tank.
To achieve this object and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a water tank comprises a tank main body provided with a water storage space formed therein and a discharge hole; a tank cover connected to the tank main body for opening and closing the water storage space; a valve movably installed in the tank main body for opening and closing the discharge hole; and a valve driving unit moving the valve using magnetic force so as to cause the valve to open and close the discharge hole.
The valve driving unit includes a movable magnet movably installed on the tank cover; and a stationary magnet installed on the valve.
Preferably, the tank cover includes a guide unit for guiding the movement of the movable magnet.
More preferably, the guide unit includes guide slots formed in the upper surface of the tank cover.
The valve includes a first elastic member for providing restoring force in the direction opposite to the attractive force between the movable magnet and the stationary magnet.
Preferably, the movable magnet is provided with a lever for facilitating the movement of the movable magnet.
Further, preferably, the tank cover includes second elastic members for providing restoring force in the direction of moving the movable magnet far away from the stationary magnet.
The valve includes a valve bracket installed in the discharge hole and provided with a water supply hole; and a valve main body provided with a stationary magnet installed thereon and serving to open and close the water supply hole.
Preferably, water leak prevention rib is provided on the lower surface of the tank main body adjacent to the discharge hole.
In another aspect of the present invention, a refrigerator having a water tank, comprises a tank main body installed on the rear surface of a door, and provided with a water storage space formed therein and a discharge hole; a tank cover connected to the tank main body for opening and closing the water storage space; a valve movably installed in the tank main body for opening and closing the discharge hole; and a valve driving unit moving the valve so as to cause the valve to open and close the discharge hole, and including a movable magnet movably installed on the tank cover and a stationary magnet installed on the valve.
A lever for facilitating the movement of the movable magnet is protruded from the movable magnet.
The water tank is installed under a door basket, and an interlocking protrusion for moving the lever close to the stationary magnet, when the water tank is installed, is formed on the door basket.
Preferably, the tank cover includes guide slots for guiding the movement of the movable magnet.
More preferably, the valve includes a first elastic member for providing restoring force in the direction opposite to the attractive force between the movable magnet and the stationary magnet.
The valve includes a valve bracket installed in the discharge hole and provided with a water supply hole; and a valve main body provided with the stationary magnet installed thereon and serving to open and close the water supply hole.
Preferably, the tank cover includes second elastic members for providing restoring force in the direction of moving the movable magnet far away from the stationary magnet.
More preferably, a water leak prevention rib is provided on the lower surface of the tank main body adjacent to the discharge hole.
Due to the above construction, it is possible to prevent water stored in the water tank from leaking out in a process of attaching or detaching the water tank to or from the rear surface of the door of the refrigerator.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.



BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
FIG. 1 is an exploded perspective view of a water tank in accordance with the present invention;
FIG. 2 is a longitudinal sectional view of FIG. 1;
FIGS. 3 and 4 are longitudinal sectional views illustrating a process of storing water in a water storage space of the water tank of FIG. 1;
FIGS. 5 to 7 are longitudinal sectional views illustrating a process of opening and closing a valve of the water tank of FIG. 1;
FIG. 8 is a front view illustrating the internal structure of a conventional refrigerator;
FIG. 9 is an exploded perspective view of a water tank provided in the refrigerator of FIG. 8; and
FIG. 10 is a longitudinal sectional view of the water tank in a state in which the water tank is installed on a door of the refrigerator of FIG. 8.



DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
FIG. 1 is an exploded perspective view of a water tank in accordance with the present invention, and FIG. 2 is a longitudinal sectional view of FIG. 1.
As shown in FIGS. 1 and 2, a water tank 51 in accordance with the present invention includes a tank main body 52, a tank cover 53, a valve 55, and a valve driving unit having a movable magnet Mg1 and a stationary magnet Mg2.
The tank main body 52 stores water for making ice, and has a polyhedral shape, the upper portion of which is opened. A water storage space 52s for storing a designated amount of water is provided in the tank main body 52. At least a part of the tank main body 52 is made of a transparent material or a semi-transparent material so that the amount of the water stored in the water storage space 52s of the water tank 51 can be recognized from the outside.
A support protrusion 52a is provided on the inner surface of the edge of the tank main body 52. The support protrusion 52a is protruded from the upper end of the inner surface of the edge of the tank main body 52 to a designated thickness. The edge of the lower surface of the tank cover 53, which will be described later, is supported by the upper surface of the support protrusion 52a. 
A knob part 52b is provided on one side of the lower surface of the tank main body 52. The knob part 52b is held by user's hand so as to attach and detach the water tank 51 to and from a mounting space provided on the rear surface of the freezing chamber door 11a, and is formed by upwardly indenting a part of the lower surface of the tank main body 52.
A guide groove 52c is formed in the lower surface of the tank main body 52. The guide groove 52c serves to guide the water tank 51 in a process of installing or removing the water tank 51 in or from the mounting space. The guide groove 52c is formed by upwardly indenting a part of the lower surface of the tank main body 52 including a discharge hole 52h to a designated height.
When the water tank 51 is installed in or separated from the mounting space, the water tank 51 slides under the condition that a guide rib 17a provided on the bottom surface of the mounting space, i.e., on the upper surface of a first ice maker housing 17, is inserted into both side ends of the guide groove 52c. 
The discharge hole 52h is formed through a designated position of the lower surface of the tank main body 52, and water stored in the water storage space 52s of the water tank 51 is supplied to an ice tray for making ice through the discharge hole 52h. The discharge hole 52h is connected to a water supply hole 17h formed through the upper surface of the first ice maker housing 17.
An insertion rib 52r is provided on the lower surface of the tank main body 52 corresponding to the circumference of the discharge hole 52h. The insertion rib 52r is protruded downwardly to a designated height.
A water leak prevention rib 52d is provided on the lower surface of the tank main body 52 adjacent to the discharge hole 52h. The water leak prevention rib 52d is protruded downwardly from the lower surface of the tank main body 52 adjacent to the discharge hole 52h. When the water tank 51 is installed in the mounting space, the lower end of the water leak prevention rib 52d contacts closely the upper surface of the first ice maker housing 17 adjacent to the water supply hole 17h. 
The tank cover 53 for selectively opening and closing the water storage space 52s of the water tank 51 is connected to the upper portion of the tank main body 52, and the edge of the lower surface of the tank cover 53 is supported by the upper surface of the support protrusion 52a under the condition that the tank cover 53 is connected to the tank main body 52. Here, the upper surface of the tank cover 53 is coplanar with the upper end of the edge of the tank main body 52.
A supply hole 53h is formed through a designated position of the tank cover 53, and water supplied from an external water source (not shown) is stored in the water storage space 52s of the water tank 51 through the supply hole 53h. A packing groove 53a is formed in the upper surface of the tank cover 53. The packing groove 53a surrounds the supply hole 53a such that the packing groove 53a is separated from the circumference of the supply hole 53a by a designated distance.
A receipt stage 53b is formed on the tank cover 53. The receipt stage 53b is obtained by stepping a part of the tank cover 53 including the supply hole 53h and the packing groove 53a. A supply hole cover 54, which will be described later, is laid on the receipt stage 53b under the condition that the supply hole cover 54 closes the supply hole 53h of the tank cover 53.
A knob groove 53c is formed in the tank cover 53, and is connected to the receipt stage 53b. The knob groove 53c is a portion, into which a user's hand is inserted, for rotating the supply hole cover 54 against the tank cover 53. For this reason, the knob groove 53c is obtained by indenting a part of the tank cover 53 more deeply than the receipt stage 53b. 
A guide frame 53d is provided on the upper surface of the tank cover 53 adjacent to the receipt stage 53d. The guide frame 53d has an approximately rectangular shape, and is located above the discharge hole 52h under the condition that the tank cover 53 is connected to the upper portion of the tank main body 52.
In this embodiment, as shown in FIGS. 1 and 2, the guide frame 53d is extended in the direction of the short side of the tank cover 53 so that one end of the guide frame 53d is located just above the discharge hole 52h. The guide frame 53d has a pair of guide slots 53e for guiding the movement of the movable magnet Mg1, which will be described later, and the guide slots 53e are respectively formed in the inner surfaces of members of the guide frame 53d, which are prepared in a pair so as to be opposite to each other.
Further, the supply hole cover 54 serving to selectively open and close the supply hole 53h of the tank cover 53 is provided. The supply hole cover 54 has one end, which is hinged to the tank cover 53, and the other end, which is vertically rotated on the hinged end. The supply hole cover 54 is laid on the receipt stage 53b under the condition that the supply hole cover 54 closes the supply hole 53h of the tank cover 53.
A contacting protrusion 54a and a packing protrusion 54b are provided on the lower surface of the supply hole cover 54. The contacting protrusion 54a and the packing protrusion 54b are protruded downwardly from positions of the lower surface of the supply hole cover 54, corresponding to the circumference of the supply hole 53h of the tank cover 53 and the packing groove 53a, to designated lengths.
Under the condition that the supply hole cover 54 closes the supply hole 53h of the tank cover 53, the outer circumferential surface of the contacting protrusion 54a contacts the inner surface of the supply hole 53h. Further, under the condition that the supply hole cover 54 closes the supply hole 53h of the tank cover 53, the packing protrusion 54b is inserted into the packing groove 53a. 
With reference to FIG. 2, there is provided the valve 55 for selectively opening and closing the discharge hole 52h of the tank main body 52. That is, the valve 55 serves to selectively supply the water stored in the water storage space 52s of the tank main body 52 to the ice tray. For this reason, the valve 55 is vertically movably installed under the condition that the valve 55 passes through the discharge hole 52h of the tank main body 52.
A valve bracket 56 of the valve 55 is provided along the circumference of the discharge hole 52h of the tank main body 52, and a water supply hole 56h for substantially supplying the water stored in the water storage space 52s to the ice tray therethrough is formed through the valve bracket 56.
The upper surface of the valve bracket 56 is downwardly inclined toward the water supply hole 56h. A receipt groove 56a is formed in a designated position of the upper surface of the valve bracket 56 adjacent to the water supply hole 56h, and the outer circumferential surface of a packing ring 58a, which will be described later, is laid on the receipt groove 56a. 
An insertion groove 56b is formed in the upper surface of the valve bracket 56, and the insertion rib 52r of the tank main body 52 is inserted into the insertion groove 56b. A fixing hook 56c is provided on the upper surface of the valve bracket 56 inside the insertion groove 56b. 
Here, the valve bracket 56 is fixed to the lower surface of the tank main body 52 by catching the fixing hook 56c onto the bottom surface of the tank main body 52 under the condition that the insertion rib 52r is inserted into the insertion groove 56b. 
A valve main body 57, which passes through the water supply hole 56h of the valve bracket 56 and is vertically movable, is installed, and serves to selectively open and close the water supply hole 56h of the valve bracket 56. That is, when the water tank 51 is installed in the mounting space, the valve main body 57 moves upwardly by means of the attractive force between the movable magnet Mg1 and the stationary magnet Mg2 of the valve driving unit, and thus opens the water supply hole 56h of the valve bracket 56.
An insertion groove 57a, into which the inner circumferential surface of the packing ring 58a is inserted, is formed in one side of the outer circumferential surface of the valve main body 57. Further, a flange part 57f, the upper surface of which supports one end of a first elastic member 59, is provided on the lower end of the valve main body 57, and a water supply hole 57h is formed through a position of the flange part 57f corresponding to the water supply hole 56h of the valve bracket 56.
There is provided the packing ring 58a for filling a gap between the valve bracket 56 and the valve main body 57. The packing ring 58a prevents the leakage of the water stored in the water storage space 52s of the water tank 51 to the outside through the gap between the valve bracket 56 and the valve main body 57. The packing ring 58a vertically moves along the valve main body 57 under the condition that the inner circumferential surface of the packing ring 58a is inserted into the insertion groove 57a. 
A packing member 58b is provided between the insertion rib 52r of the tank main body 52 and the insertion groove 56b of the valve bracket 56, and serves to prevent the leakage of the water stored in the water storage space 52s of the water tank 51 through the gap between the insertion rib 52r and the insertion groove 56b under the condition that the insertion rib 52r is inserted into the insertion groove 56b. 
The first elastic member 59a is provided between the valve bracket 56 and the valve main body 57, and both ends of the first elastic member 59a are respectively supported by the lower surface of the valve bracket 56 and the upper surface of the flange part 57f of the valve main body 57.
The first elastic member 59a serves to prevent the water supply hole 56h of the valve bracket 56 from being voluntarily opened by the valve main body 57. For this reason, the first elastic member 59a provides the valve main body 57 restoring force in the direction of closing the water supply hole 56h of the valve bracket 56 (i.e., in the direction opposite to the attractive force between the movable magnet Mg1 and the stationary magnet Mg2).
In order to selectively move the valve main body 57 in the direction of opening the water supply hole 56h of the valve bracket 56, the movable magnet Mg1 and the stationary magnet Mg2 are provided. The movable magnet Mg1 is installed on the upper surface of the tank cover 53 such that the movable magnet Mg1 can move along the guide slots 53e, and the stationary magnet Mg2 is provided on the upper surface of the valve main body 57.
The movable magnet Mg1 and the stationary magnet Mg2 have different polarities so as to generate the attractive force therebetween. The degree of the attractive force between the movable magnet Mg1 and the stationary magnet Mg2 is enough to overcome the restoring force of the first elastic member 59a and thus move the valve main body 57 upwardly, when the movable magnet Mg1 is located adjacent to the stationary magnet Mg2, for example, just above the discharge hole 52h. 
That is, only when the movable magnet Mg1 moves to a position just above the discharge hole 52h, the attractive force between the movable magnet Mg1 and the stationary magnet Mg2 has a value larger than the elastic force of the first elastic member 59a. Accordingly, the valve main body 57 moves upwardly by means of the attractive force between the movable magnet Mg1 and the stationary magnet Mg2, and thus opens the water supply hole 56h of the valve bracket 56.
Then, when the movable magnet Mg1 becomes distant from the position just above the discharge hole 52h, the attractive force between the movable magnet Mg1 and the stationary magnet Mg2 has a value smaller than the elastic force of the first elastic member 59a. Accordingly, the valve main body 57 moves downwardly by means of the restoring force of the first elastic member 59a, and thus closes the water supply hole 56h of the valve bracket 56.
A lever L is provided at one side of the movable magnet Mg1. The lever L serves to easily move the movable magnet Mg1 along the guide slots 53e. For example, a user holds the level L by his/her hand, and then moves the movable magnets Mg1 to the position just above the discharge hole 52h along the guide slots 53e. 
Further, in the process of installing the water tank 51 in the mounting space, the level L is moved by the an interlocking protrusion 14a provided on the lower surface of a door basket 14 forming the ceiling of the mounting space, and thus moves the movable magnets Mg1 to the position just above the discharge hole 52h along the guide slots 53e. 
As shown in FIG. 2, second elastic members 59b are prepared in a pair, and are respectively provided in the guide slots 53e. The second elastic members 59b provide the movable magnet Mg1 restoring force in the direction being distant from the stationary magnet Mg2. Both ends of each of the second elastic members 59b are respectively fixed to one end of the corresponding guide slot 53e distant from the discharge hole 52h and one side of the movable magnet Mg1.
Hereinafter, functions of the water tank of the present invention and a refrigerator having the same will be described in more detail with reference to the accompanying drawings.
FIGS. 3 and 4 are longitudinal sectional views illustrating a process of storing water in the water storage space of the water tank of FIG. 1, and FIGS. 5 to 7 are longitudinal sectional views illustrating a process of opening and closing the valve of the water tank of FIG. 1.
First, as shown in FIG. 3, the supply hole cover 54 is rotated at a designated angle against the tank cover 53, and thus opens the supply hole 53h. Then, water is stored in the water storage space 52s of the water tank 51 through the supply hole 53h. Here, the supply hole 53h of the tank cover 53 and the discharge hole 52h of the tank main body 52 are separated from each other at a designated distance in the horizontal direction.
Accordingly, it is possible to prevent water from being directly discharged through the discharge hole 52h of the tank main body 52 in the process of storing the water in the water storage space 52s of the water tank 51 through the supply hole 53h of the tank cover 53.
When the water is stored in the water storage space 52s of the water tank 51, as shown in FIG. 4, the supply hole cover 54 is rotated on its one end, and thus closes the supply hole 53h. Under the condition that the supply hole 53h is closed, the water tank 51 is installed in the mounting space.
More specifically, as shown in FIG. 5, the water tank 51 slides into the mounting space, and the lower surface of the tank main body 52 contacts the upper surface of the first ice maker housing 17.
Further, the upper surface of the tank cover 53 contacts the lower surface of the door basket 14. Here, the water tank 51 slides under the condition that the guide frame 53d of the water tank 51 is inserted into a groove 14b formed in the lower surface of the door basket 14.
Thereafter, as shown in FIG. 6, when the water tank 51 continuously slides into the mounting space, the water tank 51 slides under the condition that the guide rib 17a of the first ice maker housing 17 is inserted into the guide groove 52c of the tank main body 52. That is, the installation of the water tank 51 is guided by the guide rib 17a and the guide groove 52c. 
Further, the lever L provided on the movable magnet Mg1 of the water tank 51 is pushed to the right, as shown in FIG. 6, by the interlocking protrusion 14a provided in the groove 14b. Accordingly, the movable magnet Mg1 moves to the right, i.e., towards the discharge hole 52h of the water tank 51.
Thereafter, as shown in FIG. 7, when the water tank 51 is completely installed in the mounting space, the discharge hole 52h of the water tank 51 is located at a position corresponding to the water supply hole 17 of the first ice maker housing 17. Further, the lever L continuously moves to the right by the interlocking protrusion 14a, and thus the movable magnet Mg1 is located just above the discharge hole 52h of the water tank 51.
Then, the valve main body 57 overcomes the elastic force of the first elastic member 59a due to the attractive force between the movable magnet Mg1 and the stationary magnet Mg2, and thus moves upwardly, i.e., toward the inside of the water tank 51.
Accordingly, the discharge hole 52h of the water tank 51, substantially the water supply hole 56h of the valve bracket 56, is opened, and the water stored in the water storage space 52s of the water tank 51 is supplied to the first ice maker housing 17 through the water supply hole 56h of the valve bracket 56 and the water supply hole 57h of the valve main body 57.
The water supplied through the water supply hole 56h of the valve bracket 56 is supplied to the ice tray via the water supply hole 17h of the first ice maker housing 17. Here, the water leak prevention rib 52d provided on the lower surface of the tank main body 52 prevents the water stored in the water storage space 52s of the water tank 51 from leaking to the upper surface of the first ice maker housing 17 in the process of supplying the water to the ice tray.
On the other hand, in order to store water in the water storage space 52s of the water tank 51 or wash the water tank 51, the water tank 51 is removed from the mounting space.
A process of removing the water tank 51 from the mounting space is carried out in the reverse order of the process of installing the water tank 51 in the mounting space. That is, a user holds the level L by his/her hand, and moves the movable magnets Mg1 to the right in FIGS. 5 to 7. Thereby, the water tank 51 is removed from the mounting space.
Then, the movable magnet Mg1, which was located just above the stationary magnet Mg2, i.e., the discharge hole 52h of the water tank 51, by the locking protrusion 14a, is distant from the position just above the discharge hole 52h by the elastic force of the second elastic members 59b. Accordingly, the valve main body 57 moves downwardly, and thus closes the water supply hole 56h of the valve bracket 56.
The above-described water tank of the present invention and the refrigerator having the same, exhibit effects, as described below.
The discharge hole for supplying water stored in the water storage space in the water tank to the outside of the water tank is selectively opened and closed by the valve moving by means of the attractive force between the movable and stationary magnets of the valve driving unit, thereby preventing the water stored in the water storage space from leaking through the discharge hole in a process of operating the valve, and thus allowing the refrigerator to be more cleanly used.
Further, as soon as the water tank is installed on the mounting space of the refrigerator, the water stored in the water storage space in the water tank can be supplied to the outside of the water tank. Thereby, any separate work for supplying the water stored in the water tank to the outside of the water tank is not required. Moreover, since the movable and stationary magnets are returned to their original positions by means of the restoring force of the elastic members, the water tank is conveniently installed in or removed from the mounting space of the refrigerator.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

## Claims

1. A refrigerator having a water tank, said water tank comprising:
a tank main body installed on the rear surface of a door, and provided with a water storage space formed therein and a discharge hole;
a tank cover connected to the tank main body for opening and closing the water storage space;
a valve movably installed in the tank main body for opening and closing the discharge hole; and
a valve driving unit moving the valve so as to cause the valve to open and close the discharge hole, and including a first magnet movably installed on the tank cover and a second magnet installed on the valve,
wherein a lever for facilitating the movement of the first magnet is protruded from the first magnet, and
wherein the water tank is installed under a door basket, and an interlocking protrusion for moving the lever close to the second magnet, when the water tank is installed, is formed on the door basket.

2. The refrigerator according to claim 1, wherein the tank cover includes guide slots for guiding the movement of the first magnet.

3. The refrigerator according to claim 1, wherein the valve includes a first elastic member for providing restoring force in the direction opposite to the attractive force between the first magnet and the second magnet.

4. The refrigerator according to claim 1, wherein the valve includes:
a valve bracket installed in the discharge hole and provided with a water supply hole; and
a valve main body provided with the second magnet installed thereon and serving to open and close the water supply hole.

5. The refrigerator according to claim 1, wherein the tank cover includes second elastic members for providing restoring force in the direction of moving the first magnet from the second magnet to the distance large enough to prevent the first magnet from exerting enough force on the second magnet to move the second magnet in the vertical direction to actuate the valve.

6. The refrigerator according to claim 1, wherein a water leak prevention rib is provided on the lower surface of the tank main body adjacent to the discharge hole.