WO2007108645A1

WO2007108645A1 - Automatically regeneratable soft water washing apparatus

Info

Publication number: WO2007108645A1
Application number: PCT/KR2007/001371
Authority: WO
Inventors: Nam Kyu Sun
Original assignee: Nine Tech Co., Ltd.
Priority date: 2006-03-21
Filing date: 2007-03-21
Publication date: 2007-09-27
Also published as: KR100857460B1; KR20070096223A; CN101041931A; JP2009530016A

Abstract

A soft water washing apparatus having an automatic regeneration function is disclosed. The soft water washing apparatus of the present invention includes a washing tub (110), which is provided in an apparatus housing (100), a soft water processing unit (200), which supplies soft water into the washing tub (110), and a regeneration processing unit (300), which produces salt water having a predetermined concentration to supply the salt water to an ion exchange resin (240) provided in the soft water processing unit. Thus, when a predetermined amount of salt is input into the regeneration processing unit (300), salt water having a predetermined concentration is automatically produced, and the ion exchange resin (240) of the soft water processing unit (200) is automatically regenerated by the produced salt water.

Description

AUTOMATICALLY REGENERAT ABLE SOFT WATER

WASHING APPARATUS

Technical Field

[1] The present invention relates, in general, to soft water washing apparatuses having automatic regeneration functions and, more particularly, to a soft water washing apparatus having an automatic regeneration function, which includes a washing tub provided in an apparatus housing, a soft water processing unit, which supplies soft water into the washing tub, and a regeneration processing unit, which produces salt water having a predetermined concentration to supply the salt water to ion exchange resin provided in the soft water processing unit, so that, when a predetermined amount of salt is input into the regeneration processing unit, salt water having a predetermined concentration is automatically produced, and the ion exchange resin provided in the soft water processing unit is automatically regenerated by the produced salt water. Background Art

[2] Generally, washing apparatuses are machines which can easily wash various kinds of laundry. The washing apparatuses have spread to almost all households, and are life necessities. Such a washing apparatus agitates laundry, washing water and detergent using reversible rotation of a washing tub, and thus washes the laundry using friction therebetween and the washing ability of the detergent. Here, the washing ability of the detergent varies depending on the hardness of washing water. In the case of washing water having relatively low hardness, detergent exhibits superior washing ability. In contrast, in the case of washing water having relatively high hardness, the washing ability of the detergent is reduced. Typically, the washing apparatus is connected to the water source using a water supply valve and a hose, and washes laundry using washing water supplied from the water source. Generally, service water or spring water is used as washing water and is directly supplied to wash laundry without being subjected to a water softening process. Therefore, due to the relatively high hardness of the washing water, the washing ability of the detergent is reduced, so that there is a problem in that the laundry cannot be reliably washed.

[3] To avoid the above problem and reliably wash laundry, a large amount of detergent is used. Furthermore, synthetic detergent is mainly used. "Synthetic detergent" indicates all kinds of detergent made of chemical material, such as petroleum-based hydrocarbons. Synthetic detergent is relatively inexpensive and exhibits relatively high washing ability even in cold water or hard water, and thus it is widely used. However, because synthetic detergent contains therein surfactants and subsidiary constituents such as bleaching agents, it is bad for the human body. Furthermore, there is a disadvantage in that synthetic detergent is not easily decomposed, thus causing water pollution. In addition, because synthetic detergent is not easily decomposed by microbes, residue thereof disturbs the supply of oxygen into rivers, thus reducing the self-purification ability of the rivers. As well, the residue of synthetic detergent is not completely removed by a service water purification technique. As a result, constituents of synthetic detergent are absorbed into the human body through service water and are accumulated in the human body, thus seriously affecting the human body, for example, destroying sperm, inducing birth deformations, promoting heavy metal absorption, and inducing hypertension. Moreover, in the case of synthetic detergent, the amount of residue thereof in water after a washing process has been completed is greater than that of soap. Typically, in the case where a cloth, which has passed through the washing process, is rinsed five times, if the cloth is made of cotton, 0.2% of the detergent remains, and, if the cloth is made of wool, 1.6% of the detergent remains. This detergent residue contacts the skin of a user, thus inducing skin disorders. However, because there is no appropriate substitute for synthetic detergent, despite the above problems, synthetic detergent is continually used.

[4] In an effort to overcome the above problems, when using powered or liquefied natural soap, which is made from natural fatty acid or resin acid, in the washing operation, there is proposed a washing apparatus, which includes a water softening device that softens washing water using an ion exchange resin, thus washing laundry using soft water produced through the water softening process. The washing ability of natural soap is greatly reduced in hard water, which is the major disadvantage thereof. However, in soft water, the washing ability of the natural soap is superior to that of synthetic detergent. This is based on the result of experimentation conducted by the National Institute of Environmental Research of Korea. Furthermore, in the case of completely soft water, even if the amount of natural soap used is merely 20% to 30% of the amount of natural soap typically used, the washing ability is maintained, thus reducing the economic burden induced by the use of natural soap, which is more expensive than synthetic detergent. Furthermore, this can fundamentally prevent environmental pollution and avoid skin problems due to detergent residue.

[5] Meanwhile, a conventional soft water washing apparatus includes a softening device, which has ion exchange resin to absorb and remove ionic impurities and a soft water tank containing the ion exchange resin therein. The conventional soft water washing apparatus further includes a salt water tank, which contains salt water therein, and a support means, which supports the salt water tank and is attached to a wall adjacent to the installation position of the washing apparatus. The conventional soft water washing apparatus further includes a supply pump, which supplies salt water from the salt water tank, supported by the support means, into the soft water tank, and a regenerating water supply pipe and a control valve.

[6] However, the conventional soft water washing apparatus is disadvantageous in that an expensive corrosion-resistant pump must be used as the supply pump, which supplies salt water into the soft water tank, to prevent the supply pump from being corroded by salt water, thus increasing the costs of manufacturing the washing apparatus.

[7] In addition, in the conventional soft water washing apparatus, the user must directly mix salt with water to produce salt water having a predetermined concentration and input the produced salt water into the washing apparatus. Therefore, the conventional soft water washing apparatus inconveniences the user. Furthermore, because the user must directly produce salt water, it is difficult to adjust the concentration of salt water. If the concentration of salt water is greater than the optimal value, salt water remains in the ion exchange resin, so that salt water may be undesirably mixed with washing water. If the concentration of salt water is less than the optimal value, the ion exchange resin is unsatisfactorily regenerated, so that a sufficient amount of soft water cannot be obtained during the washing operation. Due to these problems, the conventional soft water washing apparatus cannot be used in real life. Disclosure of Invention

Technical Problem

[8] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a soft water washing apparatus having an automatic regeneration function, in which salt water having an appropriate concentration is produced, and the produced salt water is moved into a soft water processing unit by a difference in pressure without requiring the use of separate power, thus automatically regenerating an ion exchange resin, and which can be automatically operated by subsequently controlling solenoid valves, thus enhancing soft water processing ability, and in which the period of the process of regenerating the ion exchange resin is increased, so that a large amount of soft water can be produced after a single regenerating process, thus being useful.

[9] Another object of the present invention is to provide a soft water washing apparatus having an automatic regeneration function, which includes a soft water processing unit and a regeneration processing unit, so that hard water supplied into the washing apparatus can be converted into soft water, thus making it possible to use natural soap in place of synthetic detergent, thereby preventing environmental pollution due to the use of washing agents, preventing infants and people having sensitive skin from suffering from skin problems, and reducing washing agent expenses. Technical Solution

[10] In order to accomplish the above objects, the present invention provides a soft water washing apparatus having an automatic regeneration function, comprising: an apparatus housing, defining a main body of the washing apparatus; a washing tub, provided in the apparatus housing to wash laundry; a hard water supply pipe to supply hard water into the washing tub; a soft water processing unit, including a hard water inlet pipe communicating with the hard water supply pipe, a soft water processing tank having an ion exchange resin therein, a lower strainer provided in a lower end of the soft water processing tank so that hard water is drawn from the hard water inlet pipe into the soft water processing tank through the lower strainer, an upper strainer provided in an upper end of the soft water processing tank, and a soft water supply pipe, through which the upper strainer communicates with the washing tub; and a regeneration processing unit to regenerate the ion exchange resin, which is provided in the soft water processing unit, using salt water, which is produced by dissolving a predetermined amount of regenerating salt in a predetermined amount of hard water and has a predetermined concentration, the regeneration processing unit including a salt water tank, in which the predetermined amount of salt is dissolved in the predetermined amount of hard water to produce salt water, the salt water storing and supplying the produced salt water, a water level sensor provided in an upper end of the salt water tank to adjust a level of the hard water to supply the predetermined amount of hard water, a salt water supply valve provided in a lower end of the salt water tank, a salt water pipe, through which the salt water discharged through the salt water supply valve is supplied into the soft water processing unit, a main salt water guide valve and a subsidiary salt water guide valve provided on the salt water pipe, and a salt net provided in the salt water tank to support the regenerating salt and control the concentration of the salt water, wherein the salt water supply valve prevents air from being drawn into the salt water tank, receives the hard water from the hard water supply pipe to dissolve the regenerating salt, and discharges the produced salt water, to supply the salt water into the soft water processing unit, and a subsidiary pipe is connected to the hard water supply pipe, the subsidiary pipe has a throat part, the throat part has an inner diameter less than an inner diameter of the subsidiary pipe, and the salt water pipe is connected to the throat part to have a shape such that the salt water pipe and the throat part cross each other.

[11] Preferably, the salt water supply valve may include: a valve casing connected to an end of the salt water supply pipe and communicating with the salt water supply pipe through an opening of the valve casing; a plurality of injection slots formed through an upper portion of the valve casing at positions spaced apart from each other in a circum- ferential direction; and a spherical body provided in the valve casing, the spherical body being movable upwards or downwards by buoyancy of the salt water in the valve casing to open or close the opening of the valve casing. The spherical body may have a specific gravity less than a specific gravity of the salt water.

[12] Furthermore, a hard water selection valve and a soft water selection valve, which change a supply path of the hard water, may be provided on the hard water supply pipe, a washing water selection valve may be provided at a downstream side of the hard water selection valve, first and second control valves may be provided on respective opposite ends of the throat part of the subsidiary pipe, a soft water supply valve may be provided on the soft water supply pipe, a drain pipe may be connected to a lower end of the washing tub, and a salt water drain valve and a drain valve may be provided on the drain pipe.

[13] In addition, each of the hard water selection valve, the soft water selection valve, the washing water selection valve, the first and second control valves, the soft water supply valve, the salt water drain valve and the drain valve is a solenoid valve, and the valves and the pipes may be made of corrosion resistant material.

Advantageous Effects

[14] In the soft water washing apparatus having an automatic regeneration function according to the present invention, to regenerate an ion exchange resin of a soft water processing unit, salt water having an appropriate concentration is produced, and the produced salt water is moved into the soft water processing unit by a pressure difference resulting from the rapid flow of guide water, without requiring the use of separate power, thus conducting an automatic regenerating process. Because all process, including a resin washing process and a pressing process, can be subsequently controlled using solenoid valves, softening ability and regenerating ability can be enhanced, thus being convenient for the user. Furthermore, the period of the process of regenerating the ion exchange resin is increased, so that a large amount of soft water can be produced after a single regenerating process. Therefore, the washing apparatus of the present invention is very useful.

[15] In addition, the soft water washing apparatus of the present invention includes a soft water processing unit and a regeneration processing unit, so that hard water supplied into the washing apparatus can be converted into soft water, thus making it possible to use natural soap in place of synthetic detergent, thereby preventing environmental pollution. As well, even if the amount of natural soap used is merely 20% to 30% of the amount of natural soap that is typically used, it exhibits a superior washing effect, similar to that when the laundry is boiled. Therefore, there is an advantage in that washing agent expenses are reduced. [16] Moreover, because soft water is used in a second rinsing process, even when fabric softener is not used, laundry can maintain the state similar to that when fabric softener is used. Because natural soap is used without using synthetic detergent and soft water is used in the second rinsing process, people having sensitive skin are prevented from suffering from skin problems.

[17] Furthermore, in the present invention, because the solenoid valves and water pipes are made of plastic, they are prevented from being corroded by salt water. In addition, the regenerating process is realized without using separate power, so that the cost of manufacturing the washing apparatus is reduced and the consumption of energy is reduced. Brief Description of the Drawings

[18] FIG. 1 is a sectional view of a soft water washing apparatus having an automatic regeneration function according to the present invention;

[19] FIG. 2 is a detailed view showing an enlargement of a portion designated by the arrow A in FIG. 1 ;

[20] FIG. 3 is a flow chart illustrating the washing operation according to the present invention; and

[21] FIG. 4 is a flow chart illustrating a washing process using soft water and a washing process using hard water according to the present invention. Best Mode for Carrying Out the Invention

[22] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[23] FIG. 1 is a sectional view of a soft water washing apparatus having an automatic regeneration function according to the present invention.

[24] As shown in the drawing, the soft water washing apparatus of the present invention includes an apparatus housing 100, which forms a main body of the washing apparatus, and a washing tub 110, which is provided in the apparatus housing 100 to wash laundry. Soft water processing units 200, each of which has an ion exchange resin 240, are disposed on opposite sides of the rear surface of the washing tub 110. A regeneration processing unit 300, which produces salt water for regeneration of the soft water processing units 200, is provided in the upper end of the apparatus housing 100. A first hard water supply pipe 120, a second hard water supply pipe 130, a subsidiary pipe 140, a salt water pipe 340, a soft water supply pipe 260 and a hard water inlet pipe 250 are connected between the washing tub 110, the regeneration processing unit 300 and the soft water processing units 200. Furthermore, a drain pipe 150 is connected to the lower end of the washing tub 110. A salt water drain valve 151 and a drain valve 152, which discharge salt water that has been used in the soft water processing units 200 to regenerate the ion exchange resin 240 and soft water and hard water, which is present in the washing tub 110, are provided on the drain pipe 150.

[25] The subsidiary pipe 140 is connected to the second hard water supply pipe 130. The subsidiary pipe 140 serves to guide the supply of salt water from the regeneration processing unit 300 to the soft water processing units 200 without using separate power. First and second control valves 141 and 142 are provided on the subsidiary pipe 140. A throat part 143, the inner diameter of which is less than that of the subsidiary pipe 140, is provided between the first and second control valves 141 and 142. The salt water pipe 340 is connected to the throat part 143 to have a shape such that they cross each other.

[26] The soft water processing units 200 are connected to the hard water inlet pipe 250, which is supplied with hard water from the first hard water supply pipe 120. Each soft water processing unit 200 includes a soft water processing tank 230, which is filled with the ion exchange resin 240, a lower strainer 210, which is provided in the lower end of the soft water processing tank 230 so that hard water is drawn from the hard water inlet pipe 250 into the soft water processing tank 230 through the lower strainer 210, an upper strainer 220, which is provided in the upper end of the soft water processing tank 230, and the soft water supply pipe 260, through which the upper strainer 220 communicates with the washing tub 110.

[27] The regeneration processing unit 300 serves to regenerate the ion exchange resin

240, which are provided in the soft water processing units 200, using salt water having a predetermined concentration. The regeneration processing unit 300 includes a salt water tank 310, which dissolves regenerating salt 360, which is in the shape of a block, to a predetermined concentration, and stores and supplies dissolved salt water, a water level sensor 320, which is provided in the upper end of the salt water tank 310 to adjust the level of salt water, and a salt water supply valve 330, which is provided in the lower end of the salt water tank 310. The salt water supply valve 330 serves to prevent air from being drawn into the salt water tank 310, to receive hard water from the hard water supply pipe 120 and supply the hard water to the salt water tank 310, and to supply salt water, produced from the regenerating salt, to the soft water processing units 200.

[28] The regeneration processing unit 300 further includes the salt water pipe 340, through which salt water is supplied from the salt water supply valve 330 into the soft water processing units 200, and a main salt water guide valve 341 and a subsidiary salt water guide valve 342, which supply salt water, drawn into the salt water pipe 340, to the soft water processing units 200 without requiring the use of separate power. The regeneration processing unit 300 further includes a salt net 350, which is provided in the salt water tank 310 to support the regenerating salt 360 and control the concentration of salt water.

[29] As shown in FIG. 2, the salt water supply valve 330 includes a valve casing 331, which is connected to an end of the salt water supply pipe 340, which supplies salt water into the soft water processing units 200, and which communicates with the salt water supply pipe 340 through an opening 335. The salt water supply valve 330 further includes a plurality of injection slots 332, which are formed through the upper portion of the valve casing 331 at positions spaced apart from each other in a circumferential direction, and a spherical body 332, which is provided in the valve casing 331 and is movable upwards or downwards by the buoyancy of salt water to open or close the opening 335 of the valve casing 331. The spherical body 332 is made of material, the specify gravity of which is lower than that of salt water. Thus, when a predetermined amount or less of salt water remains in the salt water tank 310, the spherical body 332 closes the opening 335 of the valve casing 331, thus preventing air from being drawn into the salt water pipe 340. In this state, when hard water is supplied from the first and second hard water supply pipes 120 and 130 to the opening 335 of the valve casing 331 through the salt water pipe 340, the spherical body 332 is moved upwards by supplied hard water, and thus opens the opening 335, so that the hard water is injected into the salt water tank 310 through the injection slots 332. In addition, in the case where the salt water tank 310 is filled with salt water, the spherical body 332 is moved upwards by the buoyancy of the salt water, thus opening the opening 335 of the valve casing 331, so that the salt water in the salt water tank 310 is supplied into the soft water processing units 200 through the opening 335 and the salt water pipe 340.

[30] Furthermore, as valves used in the arranged pipes, there are a hard water supply valve 121, a hard water selection valve 122 and a soft water selection valve 251, which change the path along which hard water, supplied through the first hard water supply pipe 120, passes, a washing water selection valve 131, which is provided on the second hard water supply pipe 130 connected to the hard water selection valve 122 and supplies hard water into the washing tub 110 or the subsidiary pipe 140, the first and second control valves 141 and 142, which are provided on the subsidiary pipe 140, a soft water supply valve 261, which is provided on the soft water supply pipe 260, and a salt water drain valve 151, which discharges salt water that has been used to regenerate the ion exchange resin 240 in the soft water processing units 200. Each valve 122, 251, 131, 141, 142, 261, 151 may comprise a solenoid valve.

[31] The present invention, having the above-mentioned construction, conducts a process of automatically regenerating the ion exchange resin 240. The regenerating process will be described in detail herein below.

[32] First, to produce salt water having a predetermined concentration in the regeneration processing unit 300, in a state in which the hard water selection valve 122, the first control valve 141 and the main salt water guide valve 341 are opened and the soft water selection valve 251 and the second control valve 142 are closed, hard water is supplied into the salt water tank 310 of the regeneration processing unit 300 through the first and second hard water supply pipes 120 and 130, the subsidiary pipe 140, the salt water pipe 340 and the salt water supply valve 330. Here, the salt water supply valve 330 is disposed at a lower position in the salt water tank 310 and is constructed such that hard water is injected upwards into the salt water tank 310 to rapidly dissolve the regenerating salt 360. Here, to produce salt water having a concentration ranging from 10% to 12%, the regenerating salt is used in units having a predetermined size (for example, in lkg or 2kg units). Furthermore, when a predetermined amount of hard water is supplied into the salt water tank, the supply of hard water is interrupted by the water level sensor 320, which adjusts the level of hard water supplied through the salt water supply valve 330 and thus adjusts the amount of hard water. Therefore, an appropriate amount of regenerating salt is supplied to an appropriate amount of hard water under the control of the water level sensor 320, so that, after a predetermined time has passed, salt water having a concentration ranging from 10% to 12% is produced in the regeneration processing unit 300.

[33] Thereafter, the hard water selection valve 122, the first and second control valves

141 and 142 and the drain valve 152 are opened, and, simultaneously, the soft water selection valve 251, the washing water selection valve 131, the main salt water guide valve 341 and the subsidiary salt water guide valve 342 are closed. Then, hard water is drained outside through the second hard water supply pipe 130, the subsidiary pipe 140, and the drain pipe 150.

[34] Meanwhile, when hard water passes through the throat part 143 of the subsidiary pipe 140, the flow rate thereof increases, because the throat part 143 is reduced in diameter. Therefore, the pressure of hard water is reduced in the throat part 143. At this time, when the salt water supply valve 330 and the main salt water guide valve 341 are opened (turned on), due to the difference in pressure between the salt water supply valve 330 of the salt water pipe 340 and the throat part 143 of the subsidiary pipe 140, salt water is drained outside through the salt water pipe 340 and the drain pipe 150 after passing through the salt water supply valve 330.

[35] In this state, when the supply of hard water is interrupted, when the first and second control valves 141 and 142 and the soft water supply valve 261 are closed, and when the main salt water guide valve 341 and the salt water drain valve 151 are opened, salt water is supplied into the soft water supply pipe 260 by the difference in pressure between the throat part 143 of the subsidiary pipe 140 and the salt water supply valve 330. Subsequently, salt water is supplied to the soft water processing units 200 through the upper strainers 220 of the soft water processing units 200 without requiring the use of separate power. The ion exchange resin 240 is regenerated by salt water supplied through the above-mentioned process.

[36] As such, in the present invention, the throat part 143 is provided at the position, at which the subsidiary pipe 140 and the salt water pipe 340 are connected to and cross each other. Thus, salt water can be moved from the regeneration processing unit 300 to the soft water processing units 200 without requiring the use of separate power.

[37] Furthermore, salt water, which is supplied to the upper strainer 220 of each soft water processing unit 200, passes through the ion exchange resin 240, which is provided in the soft water processing unit 200, thus regenerating the ion exchange resin 240. Thanks to the regenerating operation of the salt water, the ion exchange resin 240 is able to absorb a sufficient amount of sodium ions and discharge hard constituents, such as calcium and magnesium ions.

[38] Salt water, which has passed through the ion exchange resin 240, is moved to the hard water inlet pipe 250 through the lower strainers 210 of the soft water processing units 200. Salt water, which has been moved to the hard water inlet pipe 250, is drained outside the washing apparatus through the drain pipe 150, because the salt water drain valve 151 is in the open state. As such, the ion exchange resin 240 can be automatically regenerated.

[39] During the above-mentioned regenerating process, after the supply of salt water has been completed, a resin washing process of removing salt that has adhered to the ion exchange resin 240 is conducted. Simultaneously, a pressing process is conducted along with the resin washing process. The resin washing process and the pressing process are conducted in a manner similar to the method of supplying salt water, but, during the resin washing process and the pressing process, the main salt water guide valve 341 is closed, and the subsidiary salt water guide valve 342 is opened, thus removing salt from the ion exchange resin 240.

[40] The frequency of the regenerating process may be changed depending on the capacity of the ion exchange resin 240. Preferably, after approximately four tons of soft water has been used, one regenerating process is conducted. Here, salt, which is commonly available on the market, is used as the regenerating salt 360. A predetermined amount of regenerating salt is dissolved in an appropriate amount of hard water under the control of the water level sensor, such that, after a predetermined time has passed, salt water having a concentration ranging from 10% to 12% is produced. Here, the amount of salt supplied at one time is determined in units of 500g to lkg. In the soft water regeneration washing apparatus according to the present invention, because salt water having a relatively high concentration is used to conduct the regenerating process, all of the valves and pipes used in the washing apparatus are preferably made of corrosion resistant material such as plastic, so that the valves and pipes can prevented from being corroded.

[41] The washing operation of the washing apparatus of the present invention, having the above-mentioned construction and conducting the regenerating process, will be explained in detail herein below with reference to the drawings. FIG. 3 is a flow chart illustrating the washing operation according to the present invention. FIG. 4 is a flow chart illustrating a washing process using soft water and a washing process using hard water according to the present invention. As shown in FIG. 3, the washing operation of the washing apparatus includes a washing process, a first rinsing process, a second rinsing process and a spin-drying process. The washing operation is controlled by a control unit 400. The washing process is classified into a hard water washing process and a soft water washing process. During the first rinsing process, hard water is used. During the second rinsing process, soft water is used. The number of repetitions of a first rinsing process can be determined by a user. Furthermore, depending on the user, synthetic detergent or natural soap may be used as the washing agent. Such natural soap is made from fatty acids or resin acids. As such, because animal or vegetable oil and fat, obtained from nature, are used, the natural soap is harmless to the human body and can be decomposed through fermentation or by bacteria, thus preventing environmental pollution. Furthermore, compared to synthetic detergent, natural soap has superior washing ability in soft water, so that it exhibits an effect similar to that when laundry is boiled. In addition, the present invention can reduce the amount of natural soap used to 20% to 30% of the amount of natural soap typically used, thus reducing washing agent expenses. In consideration of environmental pollution, it is preferable that synthetic detergent not be used, but, in the present invention, even if synthetic detergent is used, it is sufficient if synthetic detergent is used in an amount equal to merely 20% to 30% of the typical amount. As such, the present invention ensures superior washing ability. Furthermore, thanks to the use of soft water during the second rinsing process and the use of natural soap during the washing process, the present invention can prevent infants and people having sensitive skin from suffering from skin problems.

[42] The washing process will be described herein below. The user first chooses between a hard water washing process and a soft water washing process. In the case of the hard water washing process, as shown in FIG. 4, when the user pushes a hard water washing button after inserting laundry and natural soap into the washing tub 110, hard water is supplied from the first hard water supply pipe 120. The supplied hard water is moved to the second hard water supply pipe 130, because the hard water selection valve 122 is in the open state and the soft water selection valve 251 is in the closed state. The hard water, which is moved to the second hard water supply pipe 130, is supplied into the washing tub 110, while the washing water selection valve 131 is in the open (ON) state. Thereafter, the washing tub 110, which is supplied with hard water, is rotated to wash the laundry. After the washing process has been completed, the drain valve 152 is opened, so that the hard water is drained from the washing tub to the outside of the washing apparatus through the drain pipe 150.

[43] Meanwhile, to conduct the soft water washing process, when the user pushes the soft water washing button after laundry and natural soap are put in the washing tub, hard water is supplied from the hard water supply pipe 120, and the soft water selection valve 251 is opened and the hard water selection valve 122 and the salt water drain valve 151 are closed. The hard water is moved to the hard water inlet pipe 250 and is supplied into the soft water processing units 200 through the lower strainers 210 of the soft water processing units 200. The hard water, which has been supplied into the soft water processing units 200, passes through the ion exchange resin 240. At this time, the ion exchange resin 240, which contained a sufficient amount of sodium ions, obtained through the regenerating process, absorbs calcium ions and magnesium ions, which are contained in the hard water and increase the hardness of the water, thus converting the hard water into soft water. As such, each soft water processing unit 200 converts hard water, drawn through the lower strainer 210, into soft water in a reverse water flowing manner, in which the hard water passes upwards through the soft water processing unit 200. The soft water, which has been converted by the ion exchange resin 240, is discharged outside the soft water processing units 240 through the upper strainers 220, and is supplied into the washing tub 110 through the soft water supply pipe 260, while the soft water supply valve 261 is in the open state. After soft water is supplied to the washing tub 110, the washing process is conducted by rotation of the washing tub 110. After the washing process has been completed, soft water is discharged from the washing tub 110 to the drain pipe 150 through the drain valve 152.

[44] Furthermore, the washing apparatus is constructed such that the laundry, which has been washed through the hard water or soft water washing process, is primarily rinsed using hard water, which is supplied in the same manner as that when hard water is supplied into the washing tub 110 for the hard water washing process, and is secondarily rinsed using soft water, which is supplied in the same manner as that when soft water is supplied into the washing tub 110 for the soft water washing process. After the second rinsing process using soft water has been completed, a spin-drying process is conducted, thus completing the washing operation.

[45] As described above, because the washing apparatus of the present invention conducts the washing operation using soft water and natural soap is used during the washing process, even though the amount of washing agent used is merely 20% to 30% of the amount of washing agent used in the conventional art, the present invention can exhibit an effect similar to that when laundry is boiled. Furthermore, in the case of synthetic detergent, even if the amount of washing agent used is merely 20% to 30% of the amount of washing agent used in the conventional art, the present invention can also exhibit an effect similar to that when laundry is boiled. In addition, because the second rinsing process is conducted using soft water, even though a fabric softener is not used, the softness of the laundry can be maintained. As well, thanks to the use of soft water and natural soap, environmental pollution is prevented, and patients having sensitive skin diseases can avoid skin problems such as atopic dermatitis. Moreover, because the ion exchange resin can be automatically regenerated, the washing apparatus of the present invention can be used in actual life.

[46] Although the preferred embodiment of the present invention has been disclosed for illustrative purposes, the present invention is not limited to the preferred embodiment, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

[1] A soft water washing apparatus having an automatic regeneration function, comprising: an apparatus housing, defining a main body of the washing apparatus; a washing tub, provided in the apparatus housing to wash laundry; a hard water supply pipe to supply hard water into the washing tub; a soft water processing unit, comprising: a hard water inlet pipe communicating with the hard water supply pipe; a soft water processing tank having an ion exchange resin therein; a lower strainer provided in a lower end of the soft water processing tank so that hard water is drawn from the hard water inlet pipe into the soft water processing tank through the lower strainer; an upper strainer provided in an upper end of the soft water processing tank; and a soft water supply pipe, through which the upper strainer communicates with the washing tub; and a regeneration processing unit to regenerate the ion exchange resin, which is provided in the soft water processing unit, using salt water, which is produced by dissolving a predetermined amount of regenerating salt in a predetermined amount of hard water and has a predetermined concentration, the regeneration processing unit comprising: a salt water tank, in which the predetermined amount of salt is dissolved in the predetermined amount of hard water to produce salt water, the salt water storing and supplying the produced salt water; a water level sensor provided in an upper end of the salt water tank to adjust a level of the hard water to supply the predetermined amount of hard water; a salt water supply valve provided in a lower end of the salt water tank; a salt water pipe, through which the salt water discharged through the salt water supply valve is supplied into the soft water processing unit; a main salt water guide valve and a subsidiary salt water guide valve provided on the salt water pipe; and a salt net provided in the salt water tank to support the regenerating salt and control the concentration of the salt water, wherein the salt water supply valve prevents air from being drawn into the salt water tank, receives the hard water from the hard water supply pipe to dissolve the regenerating salt, and discharges the produced salt water, to supply the salt water into the soft water processing unit, and a subsidiary pipe is connected to the hard water supply pipe, the subsidiary pipe has a throat part, the throat part has an inner diameter less than an inner diameter of the subsidiary pipe, and the salt water pipe is connected to the throat part to have a shape such that the salt water pipe and the throat part cross each other.

[2] The soft water washing apparatus according to claim 1, wherein the salt water supply valve comprises: a valve casing connected to an end of the salt water supply pipe and communicating with the salt water supply pipe through an opening of the valve casing; a plurality of injection slots formed through an upper portion of the valve casing at positions spaced apart from each other in a circumferential direction; and a spherical body provided in the valve casing, the spherical body being movable upwards or downwards by buoyancy of the salt water in the valve casing to open or close the opening of the valve casing, wherein the spherical body has a specific gravity less than a specific gravity of the salt water.

[3] The soft water washing apparatus according to claim 1, wherein a hard water selection valve and a soft water selection valve, which change a supply path of the hard water, are provided on the hard water supply pipe, a washing water selection valve is provided at a downstream side of the hard water selection valve, first and second control valves are provided on respective opposite ends of the throat part of the subsidiary pipe, a soft water supply valve is provided on the soft water supply pipe, a drain pipe is connected to a lower end of the washing tub, and a salt water drain valve and a drain valve are provided on the drain pipe.

[4] The soft water washing apparatus according to claim 3, wherein each of the hard water selection valve, the soft water selection valve, the washing water selection valve, the first and second control valves, the soft water supply valve, the salt water drain valve and the drain valve is a solenoid valve, and the valves and the pipes are made of corrosion resistant material.