Cooling water stirrer and water purifier having the same

A stirrer includes a stirring shaft; a plurality of mixing wings extending from the lower end of the stirring shaft and spaced from each other around the stirring shaft; and a conical hub connecting the lower ends of the mixing wings.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to Korean Patent Application No. 10-2016-0106890 filed on Aug. 23, 2016 in Korea, and the contents of which are hereby incorporated by reference in its entirety under Articles 119 (35) and 365 (35) of the U.S. Patent Law.

BACKGROUND

The present disclosure relates to a cooling water stirrer and a water purifier having the same.

A water purifier is a machine that filters undesirable substances such as dirt or heavy metals in drinking water using a physical treatment and/or a chemical treatment. An example of a water purifier structure is described in Korean Patent Application Publication No. 10-2011-0065979 (published on Jun. 16, 2011). This water purifier is a direct water purifier that includes a tank holding water or other heat-exchanging fluid, and positions a cold water pipe and an evaporator within the tank. Refrigerant in the evaporator cools the water within the tank through a first heat exchange, and purified water in the cold water coil is cooled by a second heat exchange with the cooled water in the tank.

In this water purifier, a stirrer is operated to generate a water flow in the cooling tank to promote the heat exchanges between the cooling water, the refrigerant, and the purified water flowing through the cold water pipe. For example, when the stirrer is operated, the temperature of the cooling water is maintained at more uniform levels throughout the tank so that the heat exchanges are accelerated. The stirrer is connected at one end to a stirring motor, and blades are formed at another end of the stirring shaft to generate a water flow when the stirrer is operated by the stirring motor. The blades may be classified, for example, as an axial-flow blade, a radial-flow blade, an axial radial-flow blade, or a mixed blade in accordance with the shapes of the blades and the resulting water currents caused by the blades when the stirrer is operated.

In one example, a stirrer may use axial radial-flow blades (i.e., blades that causes cooling water in the tank to move in an axial direction associated with the stirring shaft) to reduce noise due to resonance during the operation of stirrer. However, the axial radial-flow blades generate a water flow in which the cooling water moves down toward a bottom of a cooling water tank and rapidly slows such that minimal water movement occurs in certain areas of the water tank, and the overall cooling performance is reduced. Further, the axial radial-flow blades still generate some resonance noise by shaking when a stirrer is rotated.

The above reference is incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.

DETAILED DESCRIPTION

A cooling water stirrer and a water purifier having the stirrer according to embodiments of the present disclosure are described hereafter in detail with reference to the drawings.

FIG. 1is a perspective view of a water purifier according to a first embodiment of the present disclosure. Referring toFIG. 1, a water purifier10according to a first embodiment of the present disclosure is a direct hot and cold water purifier that selectively dispenses cold water or hot water. For example, the water purifier10may purify (or filter) water received from an external water source and may then heat or cool the purified water. As used herein, a “direct water purifier” is a water purifier that directly dispenses purified water to a user without storing the purified water within a tank. The direct water purifier may include a tank for holding other fluids, such as water that is used to cool the purified water.

An external shape or appearance of the water purifier10may be formed by combining a plurality of panels. In detail, the water purifier10may have a substantially cube or rectangular shape formed by combining a front panel11for a front surface, side (or lateral) panels12for side surfaces, a top panel13for a top surface, a rear panel for a rear surface, and a base (or bottom) panel for the bottom surface. Various parts for purifying water may be provided in an internal space defined by combining the panels.

An operation display unit (or user interface)14that allows a user to input instructions for operating the water purifier10and displays information regarding operation states of the water purifier10may be provided on the front panel11. The operation display unit14may include one or more buttons and may selectively emit light through the buttons. For example, when a user presses, touches, or otherwise selects a button of the operation display unit14, light may be emitted at or near the selected button so that a user can easily recognizes that the selected button, and a function associated with the selected button may be performed. In another example, the operation display unit14may include a touch screen to display information, such as a graphical user interface, and to detect a touch or other user input related to the displayed information.

In one implementation, the operation display unit14may include buttons for selecting the attributes for dispensed water, such as selecting a desired temperature for the dispensed water. For instance, the operation display unit14may include buttons for “cold” water (e.g., water cooled below a first prescribed temperature), “hot” water (e.g., water heated above a second prescribed temperature), or room-temperature water (e.g., water that is neither heated nor cooled). Furthermore, the operation display unit14may include a button indicating whether a hot water mode has been turned on or off, and the operation display unit14may display temperatures of the hot water and/or the cold water. In another example, the operation display unit14may include buttons for displaying certain quantities of the purified water to be dispensed, such as a first button for dispensing a first quantity of purified water and a second button for continuously dispensing purified water. It should be appreciated that the operation display unit14may exclude some of these buttons and/or may include other buttons for performing other functions, such as buttons to provide ice, a flavoring, or another liquid.

The water purifier10may further include a water chute15under the operation display unit14. The water chute15is operated by a user to cause the purified water to be dispensed. The water chute15opens/closes to selectively dispense purified water to the user, and water chute15may also be referred to as an opening/closing part or an opening/closing nozzle. For example, the operation of the water chute15may be controlled by one or more buttons in the operation display unit14to dispense purified room-temperature water, cold water, or hot water.

A tray for collecting water dripping from the water chute15may be provided at the lower end of the front panel11. The tray may be formed with a shape defining an internal space or cavity to receive dripping water and may have a grill-shaped cover on the top for filtering foreign substances. The tray may be moved with respect to the front panel11or removed altogether to allow a user to receive purified water in water bottles or other containers having heights that exceed a predetermined distance between the water chute15and the tray or in containers having wide bottoms. In one example, the tray may include a float or other visual indicator showing a level of waste water collected within the tray, so a user can recognize when to empty the tray.

Although not shown in the figures, several components of a cooling cycle are provided inside the panels forming the external shape of the water purifier10. In detail, the water purifier10may include one or more of a compressor that compresses a refrigerant into a high-temperature and high-pressure gaseous refrigerant, a condenser that condenses the refrigerant from the compressor into a high-temperature and high-pressure liquid refrigerant, and a condenser fan for heat exchange with the condenser. The water purifier10may further include an expansion valve that expands the refrigerant from the condenser into a low-temperature and low-pressure 2-phase refrigerant, and an evaporator (to be described below) to which the low-temperature and low-pressure 2-phase refrigerant flows after passing through the expansion valve.

The water purifier10may also include a cold water production unit, and as described below, the cold water production unit may include the evaporator and a cold water pipe or coil through which purified water flows. The water purifier10may further include a heater for heating supplied water to a set temperature. The water purifier10may further include a filter assembly that filters foreign substances from or chemically treats water received from an external water supplier. The filter assembly may include, for example, one or more of a fine physical barrier or a chemical process (e.g., a carbon module) filter.

FIG. 2is a perspective view of a cold water production unit of the water purifier according to the first embodiment of the present disclosure,FIG. 3is an exploded perspective view of the cold water production unit, andFIG. 4is a perspective view of the assembly of the cold water production unit with a cooling water tank removed. Referring toFIGS. 2 to 4, a cold water production unit (also referred to as a liquid cooler or water cooler)20according to an embodiment of the present disclosure may include: a cooling water tank21that holds cooling water or other liquid; an insulating case (not shown) to insulate the cooling water tank21from the interior air; a drain valve (not shown) that is connected to the internal space of the cooling water tank21through the insulating case; a cold water pipe (or cold water coil)22that is provided in the cooling water tank21; a separator23that is provided over the cold water pipe22in the cooling water tank21; an evaporator (or evaporator coil)24that is provided inside the water tank21and above the separator23; a stirring motor support26that is provided at a top of the cooling water tank21and functions as a cover for sealing the cooling water tank21; a stirring motor27that is fixed to the stirring motor support26and has a rotary shaft extending downward; a stirring member (or stirrer)25that is provided in the cooling water tank21and is connected to the rotary shaft of the stirring motor27; and a tank cover (not shown) that covers an open top of the cooling water tank21.

In one implementation, the drain valve may be provided through the insulating case and the cooling water tank21and may be inserted through a side of the insulating case corresponding to a portion adjacent to the bottom of the cooling water tank21. When the drain valve is opened, the water or other liquid held in the cooling water tank21can be discharged out of the water purifier10.

The cold water pipe22may be a coil that is spirally wound into a cylinder or other shape. In the cold water pipe22, vertically adjacent portions may be in contact each other or may be spaced apart at a predetermined distance from each other. Similarly, horizontally adjacent portions of the cold water pipe22may contact each other or may be spaced apart at a predetermined distance from each other.

The cold water pipe22may be, as shown in the figures, wound several times horizontally with respect to the cooling water tank21to extend in a spiral or helical direction such that the cold water pipe22includes two or more concentric layers of piping. The cold water pipe22may be doubly wound in one embodiment to form two vertical layers. In detail, the cold water pipe22may be spirally doubly wound into a substantially cylindrical shape such that the vertical side portions include two concentric layers of piping. Although examples in which the cold water pipe22is double wound into two concentric layers are discussed herein, it should be appreciated that the cold water pipe22may be spirally wound into three or more layers and positioned within the water tank21.

When the cold water pipe22is wound several times to form a coil with multiple concentric layers of piping, the heat exchange area between the purified water flowing through the cold water pipe22and the cooling water in the tank21can be relatively increased since a greater length of the cold water pipe22is positioned within the cooling water. For example, providing a greater length of the cold water pipe22within the cooling water results in a greater surface area of contact between the cold water pipe22and the cooling water. Furthermore, since the cold water pipe22is wound several times, the entire height of the cold water pipe22can be decreased in comparison to a single wound pipe of similar length. For example, if the cold water pipe22is double wound, the entire height of the cold water pipe22can be decreased by half in comparison to a single wound pipe of similar length. Accordingly, a sufficient heat exchange area may be provided between the cold water pipe22and the cooling water in the cooling water tank21, while a height of the cold water pipe22and an associated height for the cooling water tank21holding the cold water pipe22may be decreased.

The cold water pipe22may be constructed from stainless steel, brass, another metal, or other material of high thermal conductivity and may be formed by winding a hollow cylinder pipe into the double wound coil shape shown in the figures. Since the cold water pipe22may be constructed from a material and shape associated with relatively high elasticity or rigidity, such as stainless steel piping, a ‘spring-back’ of the cold water pipe22may occur due to the doubly wound shape. In spring-back, the high-rigidity object tends to return to an original shape (e.g., a straight pipe) due to a returning elastic force associated with the material and shape. In order to prevent the spring-back, one embodiment includes a holder on the bottom of the cooling water tank21(seeFIG. 8) for holding the cold water pipe22in the double wound cylinder shape, and aspects of the holder will be described in detail below.

In the cold water pipe22, an inlet end221may be connected to a channel to the water supplier, and an outlet end222may be connected to a channel to the water chute15to output the chilled purified water. Since the cold water pipe22is doubly wound, both the inlet end221and the outlet end222bend to extend in a common direction from the cold water pipe22. For example, the inlet end221and the outlet end222of the cold water pipe22may vertically extend upward toward the stirring motor support26. If the cold water pipe22is spirally wound an odd-number of times (e.g., three times, five times, etc.) to form an odd number of layers, the inlet end221and the outlet end222would be positioned at opposite vertical edges of the cold water pipe22. In this configuration, it may be complicated or difficult to support the cold water pipe22within the cold water production unit20. Accordingly, winding the cold water pipe22even-numbered times (e.g., doubly, four times, etc.) may decrease the complexity and costs of the cold water production unit20.

The separator23may be provided over the cold water pipe22and may divide the internal space of the cooling water tank21into a first space in which the evaporator24is provided and a second space in which the cold water pipe22is provided. The separator23is perforated to include openings or holes that allow a circulation of the cooling water between the evaporator24and the cold water pipe22. Accordingly, ice that is formed around the evaporator24in the first space and is larger than the perforations of the separator23cannot move to the second space and block a flow of the cooling water around the cold water pipe22.

The evaporator24may be positioned in the first space defined by the separator23(e.g., above the separator23in the figures). The evaporator24is connected to the outlet end of the expansion valve that is connected to the outlet end of the condenser. A refrigerant that flows through a refrigerant pipe forming the evaporator24cools the cooling water in the cooling water tank21by exchanging heat with the cooling water. The cooling water cools purified water flowing through the cold water pipe22by a second heat exchange.

The stirring motor support26may be provided over the separator23. The stirring motor support26is coupled to the top of the cooling water tank21, where it can cover the top of the first space receiving the evaporator24. That is, the first space may be defined between the stirring motor support26and the separator23, while the second space may be defined between the separator23and a bottom of the cooling water tank21.

A cold water intake port261may be formed at a side of the stirring motor support26. The cold water intake port261is connected to a channel to the water supplier or to channel carrying purified water from the filter assembly so that the cooling water tank21can be supplied with the cooling water. An evaporator connector241may be formed at another portion or side of the stirring motor support26. The evaporator connector241may be connected to the inlet end of the evaporator24to provide the refrigerant to the evaporator24.

The stirring member25may be positioned in a substantially middle portion of the second space, but is not limited thereto. When the stirring member25is rotated (e.g., by the stirring motor27), the cooling water is freely moved and mixed between the first space and the second space within the cooling water tank21through the separator23. Accordingly, the temperature of the cooling water cooled by the evaporator24may be more uniformly maintained throughout the inside of the cooling water tank21. The stirring member25may be formed in a blade shape or an impeller shape radially extending from the rotary shaft, as shown in the figures, but is not limited thereto and may be formed in various other shapes. The structure for mounting the stirrer25will be described in detail below.

FIG. 5is a system diagram showing a water channel associated with the water purifier10according to an embodiment of the present disclosure. Referring toFIG. 5, a water supply line L is formed from a water supplier S to the water chute15of the water purifier10, and various valves and components for purifying water may be connected to the water supply line L. In detail, the water supply line L is connected to the water supplier S, such as a faucet in a house, and a filter assembly17is provided at a predetermined portion of the water supply line L so that the filter assembly17can filter or remove foreign substances to purify the water supplied from the water supplier S.

A water supply valve61and a flow sensor70may be sequentially provided on the water supply line L connected to the outlet end of the filter assembly17. Accordingly, when the amount of water sensed by the flow sensor70reaches a desired flow rate, the water supply valve61can be controlled to maintain this flow rate. A hot water line L1, a cooling water line L2, and a cold water line L3may diverge from a predetermined portion of the water supply line L extending from the outlet end of the flow sensor70.

A purified (i.e., room temperature) water valve66may be provided at the end of the water supply line L extending from the outlet end of the flow sensor70, and a hot water valve64may be provided at the end of the hot water line L1. A cold water valve65may be provided at the end of the cold water line L3, and a cooling water valve63may be provided at a predetermined portion of the cooling water line L2. In detail, the cooling water valve63is provided at a predetermined portion of the water supply line L that connects the cooling water intake port261and the diverging point of the cooling water line L2, so cooling water valve63can control the amount of cooling water that is supplied to the cooling water tank21.

The water supply lines extending from the outlet ends of the hot water valve64, the cold water valve65, and the purified water valve66may all be connected to the water chute15. Further, as shown in the figures, the purified (i.e., room temperature) water, the cold water, and the hot water may be connected to a single output or may be connected to respective different outputs.

The drain valve18may be provided on a water supply line extending out of the cold water production unit20, as shown inFIG. 5. In another example, the drain valve18may be inserted through the cooling water tank21, as described above.

A flow control valve62may be provided at a predetermined position of the hot water line L1(e.g., after the flow sensor70), and a heater (not shown) may be connected to the hot water line L1extending from an outlet end of the flow control valve62. A hot water valve64may be provided in a portion of the water supply line L that extends from an outlet end of the heater. For example, water may be heated to a predetermined temperature in the heater after flowing through the hot water line L1, and when a hot water button of the operation display unit14is selected (or other input is received), the hot water valve64is opened to dispense hot water through the water chute15.

The separator23according to the present disclosure is described hereafter in detail with reference to the drawings.FIG. 6is a top perspective view of the separator23that is combined with the cold water production unit of the water purifier according to an embodiment of the present disclosure, andFIG. 7is a bottom perspective view of the separator23. Referring toFIGS. 6 and 7, the separator23may be molded plastic. In particular, the separator23may be made of soft bendable plastic, such as a polyethylene. The separator23is provided inside the cooling water tank21and may have a shape such that the separator23divides the internal space of the cooling water tank21into the first space within (or above) the separator23and the second space outside (or below) the separator23. A portion (e.g., a top rib236) may be fixed to an inner surface of the cooling water tank21or may be held in a desired positioned through contact with the cold water pipe22and/or the evaporator24.

In detail, the separator23may have a bottom (or bottom layer)231horizontally placed in the cooling water tank21, a first extension234extending upward from a portion of the bottom231, and a plurality of separation walls238extending upward from the bottom231to divide the first space into several spaces. The bottom231is composed of a plurality of latticed ribs231a, and holes through which cooling water flows are formed between the latticed ribs231a. Cooling water within the cooling water tank can freely move between the first space and the second space through the holes the latticed ribs231a. The bottom231may be formed in a shape that is substantially similar to a corresponding transverse plane in the cooling water tank21. For example, the peripheral size and shape of the bottom231may correspond to adjacent interior surfaces of the cooling water tank21.

A substantially circular center hole may be formed at or near the center of the bottom231, and the first extension234may extends upward from the edge of the center hole. In detail, the first extension234may have a plurality of first vertical ribs232extending upward from the edge of the center hole and a circular band-shaped first top rib233connecting the upper ends of the first vertical ribs232.

The first vertical ribs232may be arranged with substantially regular intervals around the center hole in the bottom231. The first vertical ribs232may include ribs vertically extending from (e.g., orthogonal to) a horizontal surface (e.g., from bottom231). The first vertical ribs232may further include ribs extending at an angle from the horizontal surface or that otherwise extend between two or more of vertically extending ribs. A cylindrical or a truncated conical space may be formed by the first vertical ribs232and the first top rib (or ring)233, and this space may be referred to as a stirring member hole (or stirring member cavity)233a. That is, the stirring member25may be positioned in the second space of the cooling water tank21through the stirring member hole233a. The space formed inside the first extension234(that is, the stirring member hole233a) may also be referred to herein as a “third” space.

The separation walls238are formed in planar shapes and may extend laterally from the first vertical ribs232and vertically upwards from the bottom231to divide the first space into several sub-regions. In detail, the separation walls238may be arranged at regular intervals around the center hole. Accordingly, the first space can be divided into several sub-regions defined by the first vertical ribs232, the separation walls238, and the inner side of the cooling water tank21. Therefore, ice that is formed in the first space through a heat exchange between the evaporator24and the cooling water in the tank21can remain in one of sub-regions inside the first space and is blocked from moving to the other sub-regions inside the first space.

The separation walls238may each have a seating groove238afor holding the evaporator24. That is, the refrigerant pipe of the evaporator24may be spirally wound several times through the seating grooves238aof the separation walls238. The width of the seating grooves238amay be the same as or slightly larger than an outer diameter of the refrigerant pipe of the evaporator24so that the evaporator24may be received in and supported by the seating grooves238a.

The separation walls238may be integrally formed with the bottom231. Alternatively, the separation walls238may be detachably formed. For example, the separation wall238may be detachably fitted in the bottom231or may be fitted between the first vertical ribs232and the second vertical ribs235. That is, the separation walls238may be selectively attached or detached by a user.

The separator23may further have second extensions237extending upward from an outside edge of the bottom231. In detail, the second extension237may have a plurality of second vertical ribs235extending upward from the edge of the bottom231and a second top rib (or top layer)236connecting the upper ends of the second vertical ribs235. The second top rib236may be fitted in the cooling water tank21. That is, the outer edge of the second top rib236may be brought in close contact with (e.g., within a threshold distance of) the inner interior surface of the cooling water tank21.

Coupling grooves236amay be formed at an lateral outside edge of the second top rib236, and the coupling grooves236amay be sized and positioned to fit on coupling projections (not shown) formed on the inner surface of the cooling water tank21to couple the separator23to the inner surface of the cooling water tank21. The coupling grooves236amay be formed in various shapes, quantities, or locations, depending on the shapes, quantities, or locations of the coupling projections.

The second vertical ribs235may be spaced around the edge of the bottom231and may be coupled to or otherwise extend from an upper surface of the bottom231. The second vertical ribs235are arranged around the separation walls238, and some of the second vertical ribs235may be connected to the ends of the separation walls238. The separation wall238may be positioned between the first vertical ribs232and the second vertical ribs235. Accordingly, the first space can be divided into several spaces by the first vertical ribs232, the separation walls238, and the second vertical ribs235. Therefore, as previously described, ice that is formed near the evaporator24in one of the sub-regions of the first space remains in that sub-regions and is blocked by the separation walls238from moving to the other sub-regions of the first space. Consequently, ice coming off the evaporator24does not contact the walls of the cooling water tank21, so the ice does not generate noise by impacting the cooling water tank21and does not damage the cooling water tank21.

Cold water pipe seats (or cold water pipe extensions)239may be formed in an underside of the bottom231. The cold water pipe seats239may protrude from the underside of the bottom231and may be partially stepped. For example, the cold water pipe seats239may have stepped sides that are rounded with a curvature corresponding to the outer diameter of a portion of a coiled shape formed by winding the cold water pipe22. Accordingly, an uppermost portion of the cold water pipe22can be seated on the cold water pipe seats239(seeFIG. 8).

FIG. 8is a vertical cross-sectional view taken along line X-X ofFIG. 4, andFIG. 9is a plan view of the cold water pipe22that is provided in the cooling water tank21. Referring toFIGS. 8 and 9, the internal space of the cooling water tank21is divided into the first space and the second space by the separator23and a third space for receiving the stirring member25can be formed in the first space by the first extension234, as previously described. The first space, with the exception for the third space, can be further divided into several sub-regions by the separation walls238, as also previously described. In detail, the first space may be formed over the bottom231of the separator23, and the second space may be formed under the bottom231. The first space is divided into several sub-regions by the first extension234, the separation walls238, and the second extension237.

The cold water pipe22is positioned above a bottom surface of the cooling water tank21, and the separator23is positioned over the cold water pipe22in the cooling water tank21. The outer edge of the second top rib236, formed on the top portion of the separator23, is in close contact with an inner surface of the cooling water tank21to position and fix the separator23in the cooling water tank21. The cold water pipe seats239may be formed on the underside of the bottom231and may extend downward to contact and hold a portion of the cold water pipe22in a desired positioned.

The refrigerant pipe of the evaporator24may be spirally wound inside the separator23to form a substantially round coiled shape. The coiled refrigerant pipe24may be supported in the seating grooves238aof the separation walls238to position the evaporator24in the first space.

When the stirring member25is rotated (e.g., by the storing motor27), the cooling water is circulated in the cooling water tank21, such as to flow between the first space and the second space. This motion of the cooling water helps to maintain more uniform internal temperatures within the cooling water tank21. Otherwise, water cooled by contact with the evaporator24may remain in the first space, and water warmed by contact with the cold water pipe22may remain in the second space, limiting the ability of cold water production unit20to cool the purified water passing through the cold water pipe22.

Furthermore, the movement of the cooling water caused by the stirring motion of the stirring member25helps to melt ice generated in the first space by circulating relatively warmer water toward the ice. As previously described, the ice formed in the first space by contact with the evaporator24may be isolated in the first space by the separator23so that the ice cannot be move to the second space while the cooling water can circulate between the first and second spaces. Furthermore, since the first space is divided into several sub-regions by the separation walls238of the separator23, ice formed in one of the sub-regions does not move to the other sub-regions. Thus, the ice made in the sub-regions cannot freely move within the first space to other sub-regions since the movement of the ice is limited by the separation walls238. Consequently, the separation walls238may prevent a movement or a rotation of ice within the first space or region due to a clockwise or a counterclockwise flow of water that is formed by the stirring motion of the stirring member25. Accordingly, the motion of the stirring member25does not cause the ice to move and contact the stirring member25, the cold water pipe22, the evaporator24, or the interior surface of the cooling water tank21, preventing the ice from damaging to these components and reducing noises caused by the ice impacting these components.

A holder (or holder rib)28for fixing the cold water pipe22within the second space may be formed inside the cooling water tank21. For example, the holder28may protrude a predetermined height upward from the bottom (or bottom surface)211of the cooling water tank21. In detail, the holder28may have a rib shape to receive and seat the spirally wound cold water pipe22. The holder28may include a seating groove281for receiving the cold water pipe22, and the seating groove281may be formed at the top of the holder281in a substantially U-shape. The multiple wound cold water pipe22can be partially inserted in the seating groove281such that two or more layers of the cold water pipe22are positioned in close contact with surfaces of the holder28. For example, an interior piping layer of the cold water pipe22may contact an interior vertical surface of the holder28, and an exterior piping layer of the cold water pipe22may contact an exterior vertical surface of the holder28. Accordingly, the holder28fixes and support the cold water pipe22to deter a bending of the cold water pipe22from spring-back and can prevent noise caused by a movement of the cold water pipe22within the cooling water tank21.

A plurality of holders28may be formed on the bottom211of the cooling water tank21. For example, three holders28may be formed on the bottom of the cooling water tank21and may be arranged at a predetermined distance circumferentially along the cold water pipe22. For example, the three holders28may be arranged with regular intervals such that an angle distance between two adjacent ones of the holders28is about 120°. The holders28simultaneously hold the cold water pipe22, so the cold water pipe22can be firmly fixed without moving or shaking within the cooling water tank21. However, it should be appreciated that the number of the holders28is not limited to three, and the cold water production unit20may include fewer or more holders28. Furthermore, it should be appreciated that the holders28may be spaced apart at different, non-uniform intervals as appropriate to fix the position of the cold water pipe22while providing sufficient space in the cold water production unit20for other components. For instance, the holders28may be positioned away from the drain valve18.

The structure for fixing the cold water pipe22with the components of the cold water production unit20is described hereafter with reference toFIG. 8. For example, the cold water pipe22may contact and, therefore, be fixed in a given location in the cold water production unit20by the cooling water tank21, the separator23, and the stirring motor support26. In detail, the holders28on the bottom211of the cooling water tank21may contact a lower portion of the cold water pipe22such that the lower portion of the cold water pipe22contacts the interior surfaces of the seating grooves281of the holders28. Accordingly, when the cold water pipe22is double wound to include two layers of piping, a first layer of the cold water pipe22may be supported by one surface of the seating grooves281, and a second layer of the cold water pipe22may be supported by a second surface of the seating grooves such that the two layers of the cold water pipe22are held in close contact with each other and cannot separate.

The cold water pipe seats239are formed to extend downward from the bottom of the separator23to be in close contact with a top portion of the cold water pipe22. More specifically, the top interior portion of the cold water pipe22can contact a lateral exterior surface of the cold water pipe seats239. Thus, the cold water pipe seats239may contact the innermost layer of the cold water pipe22. For example, the cold water pipe seats239and the innermost layer of the cold water pipe22may be designed to be forcibly fitted against each other, such as configuring an interior radius of the cold water pipe22to be slightly smaller than a radial distance associated with the cold water pipe seats239to cause that interior layer of the cold water pipe22to apply a compressive force against lateral exterior surfaces of the cold water pipe seats239. In this case, the cold water pipe seats239apply outward pressure to push a portion of the cold water pipe22away from a center so the cold water pipe22can be firmly supported. Furthermore, since the cold water pipe22is fitted between the holders28and the cold water pipe seats239, a spring-back due to double (or more) winding of the cold water pipe22can be prevented.

The bottom of the stirring motor support26, on which the stirring motor27is provided, may be positioned in close contact with a top of the separator23. Consequently, the bottom of the stirring motor support26may provide a downward pressing force against the separator23, and the separator23may transfer this downward pressing force against the cold water pipe22to fix the cold water pipe22more firmly against the holders28and the bottom211of the cooling water tank21.

A structure of the stirring member (or stirrer)25according to the first embodiment of the present disclosure is described hereafter in detail with reference toFIGS. 10 to 12.FIG. 10is a top perspective view of a stirrer25according to the first embodiment of the present disclosure,FIG. 11is a bottom perspective view of the stirrer25, andFIG. 12is a front view of the stirrer25. Referring toFIGS. 10 to 12, the stirrer25according to the first embodiment of the present disclosure includes a stirring shaft (or shaft)251coupled at one end to the rotary shaft of the stirring motor27. Another end of the stirring shaft251includes a plurality of mixing wings (or vanes or mixing vanes)250spaced at a predetermined from each other around the stirring shaft251, and a conical (or horn-shaped) hub256connecting the mixing wings250.

In detail, the stirring shaft251may be formed in a cylinder or bar shape and may be coupled to the rotary shaft of the stirring motor27to rotate with the rotary shaft. A coupling groove251afor fitting the rotary shaft may be formed at the top of the stirring shaft251(i.e., an end proximal to the stirring motor27) to enable the stirring motor27to drive the stirrer25. The coupling groove251amay be formed to extend a predetermined depth down from the top of the stirring shaft251to provide a space to receive the rotary shaft of the stirring motor27.

The mixing wings250are shaped to generate a water flow when the stirrer25is driven by the stirring motor27. In detail, the mixing wings250each have a body (or body extension)252extending downward from the lower end of the stirring shaft251and a blade255extending from the lower end of the body252and extending in a substantially radial direction outward from the hub256.

The bodies252extend a predetermined length downward from the lower end of the stirring shaft251such that the blades255are positioned at a lower portion in the cooling water tank21to contact the cooling water in the cooling water tank21. For example, the bodies252may formed such that the blades255are positioned at the center portion of a cavity formed within spiral wound the cold water pipe22provided near the bottom of the cooling water tank21. Accordingly, when the stirrer25is rotated, heat may be efficiently exchanged between cooling water and the cold water flowing through the cold water pipe22due to a water flow that is generated by a stirring motion by the blades255.

The blades255extend in a substantially radial direction from the hub256, beginning at the lower ends of the bodies252. Each of the blades255may have an extension (or blade extension)253positioned in the same vertical plane as the body252and a bending portion (or bending extension)254extending radially outward from the hub256and also in the circumferential direction of the hub256from the lower end of the extension253. The lower end of the bending portion254may extend between an outer, lower edge of the hub256and a central, top portion of the hub256.

When the stirrer25is rotated, the extension253of the blade255generates a radial water flow toward the sides of the cooling water tank21. In detail, the extension253radially extends outward from the lower end of the body252. The angle A between a line253aextending from the top edge of the extension253and a vertical line252apassing through the center of the stirring shaft251may be 90°. However, the present disclosure is not limited thereto, and the angle A between the line253aextending from the extension253and the vertical line252apassing through the center of the stirring shaft251may range, for example, between 70°˜110°.

The bending portion254initially extends downward from the lower end of the extension253and then extends away from vertical line252ain a circumferential direction of the hub256. When the stirrer25is rotated or otherwise driven by the stirring motor27, the bending portion254forcibly moves water to flow axially and radially toward the sides and the lower ends of the sides of the cooling water tank21.

In one example, the bending portion254is formed to extend or bend from the lower end of the extension253in a direction that is opposite to the rotational direction of the stirring motor27. For example, as shown inFIG. 12, assuming that the stirring motor27is rotated clockwise (e.g., to the left), the bending portion254may be extend in a counterclockwise (e.g., to the right) circumferential direction, opposite to the rotational direction of the stirring motor27. The angle B between an inclined plane extending through the bending portion254and a vertical plane passing through a top the bending portion254at an intersection with extension253may be 30°. However, the present disclosure is not limited thereto, and the angle B between bending portion254and the vertical plane passing through the top of the bending portion254may range, for example, between 20°˜40°.

According to this configuration of the present disclosure, when the stirring motor25is rotated, a portion of the cooling water around the blades255flows to the sides of the cooling water tank21along the extensions253of the blades255, and another portion of the cooling water flows to the sides or the lower ends of the sides of the cooling water tank21along the bending portions254of the blades255. The cooling water flowing to the sides and the lower ends of the sides of the cooling water tank21then flows back up to an upper space of the cooling water tank21where pressure is relatively low due to a pressure difference caused by the rotation of the stirrer25, and then flows back down a central portion of the cooling tank25to the blades255. Accordingly, the rotation of the stirrer25causes a circular flow in cooling tank21in which that the cooling water is freely moved and mixed between the first space associated with the evaporator24and the second space associated with cold water pipe22so the temperature of the cooling water remains relatively uniform throughout the inside of the cooling water tank21.

The hub256is formed at the lower ends of the blades255to generate a radial water flow toward the cold water pipe22when the stirrer25is rotated. In one example, the hub256may have a substantially conical shape or other shape that corresponds and connect to an interior edge of at least one of the extensions253or the bending portions254of the blades255. A lower surface of the hub256may define a hollow conical opening at a lower end of the stirrer25. The outer diameter of the lower end of the hub256may correspond to the outer diameter of the lower ends of the blades255, as shown inFIGS. 10 to 12. The hub256secures the lower ends of the blades255to prevent the lower ends of the blades255from shaking when the stirrer25is rotated. Accordingly, when the stirrer25is rotated, resonance noise due to a shaking of the blades255may be further reduced.

Further, the hub256may have a declining surface that extends outwards in a downward direction toward the edge of the hub256from the center near vertical line252a. That is, cooling water flowing downward on the extensions253or the bending portions254of the blades255then radially spreads outward along the inclined surface of the hub256. Accordingly, at least a portion of the water flow generated by the stirring motion of the blades255is directed away from the bottom of the cooling water tank21, so the cooling water flows smoothly throughout the water tank21and does not stagnate near a bottom surface of the water tank21.

Further, a plurality of air holes (or holes)256amay be formed through the hub256. In one example, the air holes256aeach may be formed between adjacent pairs of the mixing wings250. The air holes256may be formed closer to the top center than the lower edge of the hub256. Alternatively, the hub256may have a rounded top and the rounded top may be divided into several sections by at least one of the extensions253or the bending portions254. For example, the rounded top of the hub256may be divided into four sections when the stirrer25includes four extensions253or four bending portions254that are equally spaced apart, as shown in the figures, and the air hole256amay be formed in each of the four sections.

The air holes256amay discharge the air remaining inside a cavity formed inside the hub256to the outside of the hub256. In detail, when the cooling water tank21is filled with the cooling water, a small amount of air may remain inside the hub256. Then, air bubbles may be produced inside the hub256when the stirrer25is driven, and noise may be generated by the air bubbles. Accordingly, the air holes256may prevent air bubbles from being produced inside the hub256and thus, may prevent noise caused by the air bubbles. Although the air holes256are formed in each of the four sections of the hub256in the figures, the present disclosure is not limited thereto, and the air holes256amay not be formed in one or more of the sections.

FIG. 13is a perspective view showing a stirrer25according to a second embodiment of the present disclosure. The stirrer25in this second embodiment is the similar to the stirrer25of the first embodiment shown inFIGS. 10 to 12but generally excludes the bending portion254of the blades255. Accordingly, only certain aspects of the specific configuration of this second embodiment are described hereafter, and the first embodiment may be referred to for other, similarly configured aspects of the second embodiment.

Referring toFIG. 13, the stirrer25according to the second embodiment of the present disclosure includes a stirring shaft251coupled to the rotary shaft of the stirring motor27to rotate a plurality of mixing wings250extending from the lower end of the stirring shaft251and spaced at a predetermined from each other around the stirring shaft251. The stirrer25further includes a substantially conical hub256connecting the lower ends of the mixing wings250.

In detail, the mixing wings250each have a body252extending downward from the lower end of the stirring shaft251, and a blade255extending from the lower end of the body252and in the radial direction from the hub256. The blades255each also have an extension253extending in the radial direction of the hub256from the lower ends of the body252and positioned in substantially the same vertical plane as the body252.

The hub256is formed at the lower ends of the extensions253to generate a radial water flow, when the stirrer25is rotated, toward the spirally wound cold water pipe22. In detail, the hub256may have a substantially conical shape outer surface that connects to the lower interior ends of the extensions253. In the example shown inFIG. 13, substantially all of the lower ends of the extensions253are connected to the top surface of the hub256, but in another example shown inFIG. 8, only a portion of the lower ends of the extensions253are connected to the top surface of the hub256. The outer diameter of the bottom of the hub256may correspond to the outer diameter of the lower ends of the blades255, but in other examples, the outer diameter of the bottom of the hub256may be larger or smaller than the outer diameter of the blades255. The hub256secures the lower ends of the blades255to prevent the lower ends of the blades255from shaking or vibrating when the stirrer25is rotated. Accordingly, when the stirrer25is rotated, resonance noise due to shaking of the blades255may be minimized.

FIG. 14is a perspective view showing a stirrer25according to a third embodiment of the present disclosure. The stirrer25in this embodiment is the similar to the stirrer25in the first embodiment except that the hub256has an outer diameter that is relative smaller than an outer diameter of the blades255. Accordingly, only certain aspects of the specific configuration of this third embodiment are described hereafter, and the first embodiment may be referred to for other, similarly configured aspects of the stirrer25of the third embodiment.

Referring toFIG. 14, the stirrer25according to the third embodiment of the present disclosure includes a stirring shaft251coupled to the rotary shaft of the stirring motor27to rotate a plurality of mixing wings250extending from the lower end of the stirring shaft251and spaced at a predetermined from each other around the stirring shaft251. The stirrer further includes a conical hub256connecting the lower ends of the mixing wings250. In detail, the mixing wings250each have a body252extending downward from the lower end of the stirring shaft251and a blade255extending from the lower end of the body252and extending in the radial direction of the hub256.

The blades255extend in the radial direction of the hub256from the lower ends of the bodies252, and each of the blades255has an extension253positioned in the same vertical plane as the body252and a bending portion254extending in the circumferential direction of the hub256from the lower end of the extension253. The hub256is formed at the lower ends of the bending portions254to generate a radial water flow, when the stirrer25is rotated, toward the cold water pipe22. In detail, the hub256may have a substantially conical, inclined outer shape connected to corresponding lower interior ends of the extensions253and/or bending portions254. The hub256holds the lower ends of the blades255to prevent the lower ends of the blades255from shaking when the stirrer25is rotated.

The outer diameter of the bottom of the hub256may be smaller than the outer diameter of the lower ends of the blades255. For example, the outer surface of the hub256may extend to contact the interior edges of the extensions253but only a portion of the interior edges of the bending portions254. According to this configuration of the present disclosure, resonance noise due to shaking of the blades255when the stirrer25is rotated is minimized, while a contact area between cooling water and the hub is also reduced. Therefore, flow resistance of the cooling water against the hub256is reduced, so the cooling water may more smoothly circulate within the cooling tank21.

FIG. 15is a perspective view showing a stirrer25according to a fourth embodiment of the present disclosure. The stirrer25in the fourth embodiment is similar to the stirrer25in the first embodiment except that the stirrer25in the fourth embodiment includes a hub256having an outer diameter that is larger than the diameter of the blades255. Accordingly, only certain aspects of the specific configuration of this fourth embodiment are described hereafter, and the first embodiment may be referred to for other, similarly configured aspects of the stirrer25of the fourth embodiment.

Referring toFIG. 15, the stirrer25according to the fourth embodiment of the present disclosure includes a stirring shaft251coupled to the rotary shaft of the stirring motor27to rotate a plurality of mixing wings250extending from the lower end of the stirring shaft251and spaced at a predetermined from each other around the stirring shaft251. The stirrer25further includes a conical hub256connecting the lower ends of the mixing wings250.

In detail, the mixing wings250each have a body252extending downward from the lower end of the stirring shaft251and a blade255extending downward from the lower end of the body252and extending in the radial direction of the hub256. The blades255extend in the radial direction of the hub256from the lower ends of the bodies252and each have an extension253positioned in the same vertical plane as the body252. Each of the blades255also has a bending portion254radially extending outward from the hub256and further extending in the circumferential direction of the hub256from the lower end of the extension253.

The hub256is formed at the lower ends of the bending portions254to generate a water flow, when the stirrer25is rotated, toward the cold water pipe22. In detail, the hub256may have a substantially conical shape connecting the lower ends of the extensions253. The hub256holds the lower ends of the blades255to prevent the lower ends of the blades255from shaking when the stirrer25is rotated. The outer diameter of the bottom of the hub256may be larger than the outer diameter of the lower ends of the blades255. For example, the outer surface of the hub256may contact the interior edges of the extensions253and the interior edges of the bending portions254, and may further extend beyond the outer edge of the bending portions254. According to this configuration of the present disclosure, resonance noise due to shaking of the blades255caused when the stirrer25is rotated is minimized since the hub secures the lower ends of the blades255. Also, the extended hub causes the cooling water to be radially spread widely through the cooling tank25such that the cooling water can more smoothly circulate.

Aspects of the present disclosure provide a cooling water stirrer that reduces resonance noise due to a shaking of blades on the stirrer when the stirrer is rotated, and a water purifier having the cooling water stirrer. Aspects of the present disclosure also provide a cooling water stirrer that more effectively circulates water by generating a widely spreading radial water flow when a stirrer is rotated, and a water purifier having the cooling water stirrer. Aspects of the present disclosure further provide a cooling water stirrer that does not generate noise due to bubbles by preventing bubbles from being generated therein when rotating, and a water purifier having the cooling water stirrer.

A stirrer according to an aspect includes: a stirring shaft; a plurality of mixing wings extending from the lower end of the stirring shaft and spaced from each other around the stirring shaft; and a conical hub connecting the lower ends of the mixing wings.

The mixing wing each may have: a body extending downward from the lower end of the stirring shaft; and a blade bending from the lower end of the body and extending in the radial direction of the hub. The blades each may have: an extension extending in the radial direction of the hub from the lower end of the body and positioned in the same vertical plane as the body; and a bending portion extending radially and in the circumferential direction of the hub.

A water purifier according to one aspect includes: a cooling tank keeping cooling water; a separator dividing the cooling water tank into an upper space and a lower space; an evaporator provided in the upper space; a cold water pipe provided in the lower space; the stirrer provided in the lower space; and a stirring motor rotating the stirrer.

According to another aspect, a stirrer comprises a shaft; a hub having a conical outer surface; and a plurality of vanes extending between the shaft and the hub, the vanes being circumferentially spaced from each other around a central axis of the stirrer, and having lower ends connecting to the hub.

According to another aspect, a water purifier comprises a tank to hold a fluid; a stirrer provided in the tank to contact the fluid, the stirrer including: shaft; a hub having a conical outer surface; and a plurality of vanes extending between the shaft and the hub, the vanes being circumferentially spaced from each other around a central axis of the stirrer and having lower ends connecting to the hub; and a motor coupled to the stirrer and providing a rotating force to the stirrer.

It should be understood that the present disclosure may be modified in various ways within the scope of the present disclosure by those skilled in the art and the scope of the present disclosure should be construed on the basis of claims.