CN1738938A - Ion eluting unit and device provided with same - Google Patents

Abstract

A laundry machine (1) in which metal ions produced by an ion eluting unit (100) can be input into water at the last rinsing step. The time for the last rinsing step at which metal ions are input is longer than that for the step at which no metal ions are input. When metal ions are input, in the rinsing step, a strong flow time and a weak flow time are provided, or a strong flow time and a rest time are provided. If any imbalance during drying rotation of the washing tub (30) after metal ion input is detected, a processing different from that carried out if an imbalance is detected when no metal ions are input is carried out.

Description

Ion elution device and apparatus with such a device

Technical Field

The present invention relates to a washing machine capable of sterilizing laundry, and various parts in the washing machine, such as a washing tub and the like, exert a sterilizing effect by using metal ions. In particular, the present invention relates to a washing machine equipped with an ion elution device that generates metal ions by applying a voltage between electrodes.

Background

When washing laundry in a washing machine, a treatment substance is usually added to the water, especially to the rinse water. Typical examples of such treatment substances include softeners and bleaches. In addition to this, in recent years, there is an increasing need to subject clothes to antibacterial treatment.

From a hygienic point of view, it is desirable to hang the clothes under the sun to dry them. However, in recent years, with the increase in the number of women who go out to work and with the increase in the number of small households, there have been more and more households where no one is at home during the day. In these homes, the clothes can only be hung indoors for drying. Even in a household where someone is at home during the day, the clothes can be hung indoors for drying only in rainy weather.

Hanging the clothing indoors tends to promote the growth of bacteria and mold in the clothing, as compared to hanging the clothing in the sun for drying. This tendency is particularly noticeable when it takes a long time to dry the laundry due to high humidity, such as in rainy season, or low temperature. As the number of bacteria and mold increases, the laundry may become smelly. For this reason, in households, where clothes can usually only be hung indoors for drying, it is highly desirable to perform an antimicrobial treatment on textiles in order to inhibit the growth of bacteria and mold.

Today, many of the clothes available on the market have been previously treated with antibacterial/deodorant or antifungal agents. However, it is difficult to replace all textiles in the home with those that have been previously subjected to antibacterial/deodorant treatment. Furthermore, even the textiles lose efficacy of the antimicrobial/deodorizing treatment with repeated washing.

In this case, it is conceivable to perform the antibacterial treatment on the laundry at every washing. For example, japanese utility model patent publication No. h5-74487 discloses an electric washing machine equipped with an ionizer that generates metal ions such as silver ions or copper ions that exert a sterilizing effect. Japanese patent publication No.2000-93691 discloses a washing machine capable of generating an electric field by which a washing liquid is sterilized. Japanese patent publication No.2001-276484 discloses a washing machine equipped with a silver ion adding device that adds silver ions to washing water.

Summary of The Invention

An object of the present invention is to provide a washing machine capable of adding antibacterial metal ions to water within a predetermined operation during washing of laundry, and enabling the metal ions to sufficiently exert their antibacterial effects. Another object of the present invention is to provide a washing machine capable of correcting uneven distribution of laundry in consideration of the presence of metal ions added in the case where the uneven distribution of laundry is detected during rotation of a washing tub fordehydration after the metal ions are added.

In order to accomplish the foregoing object, according to the present invention, there is provided a washing machine in which antibacterial metal ions can be added to water within a predetermined operation in a laundry washing process, the washing machine being constructed such that a time of the predetermined operation is longer when metal ions are added than when metal ions are not added. It takes a certain time for the metal ions to be completely attached to the laundry. With this configuration, when metal ions are added, the treatment time is prolonged as compared with the case where metal ions are not added, so that the metal ions are satisfactorily attached to the laundry and exert their intended antibacterial action.

According to the present invention, there is provided a washing machine in which antibacterial metal ions can be added to water during a predetermined operation in a laundry washing process, the washing machine being constructed such that the predetermined operation includes a strong spinning time period and a gentle spinning time period, or a strong spinning time period and a rest time period. In order to allow the metal ions to be attached to the laundry, it is not always necessary to strongly agitate the water. With this configuration, there is a gentle swirling time period or a stationary time period in addition to the strong swirling time period, which aims to make metal ions uniformly dispersed in water and scattered to each corner of the laundry, and which aims to quietly wait for the metal ions to adhere to the laundry, so that damage to the laundry or increased power consumption can be avoided. In addition, the washing machine is slowly rotated instead of in a static state, so that a user can notice that the washing machine works, and misoperation is avoided.

According to the present invention, in the washing machine constructed as described above, the ratio of the strong spinning time period to the gentle spinning time period or the ratio of the strong spinning time period to the stationary time period is kept constant regardless of the volume of water and/or the amount of laundry in the washing tub. With this configuration, programming of the control program is made easier.

According to the present invention, in the washing machine constructed as described above, the ratio of the strong spinning time period to the gentle spinning time period or the ratio of the strong spinning time period to the stationary time period varies according to the volume of water and/or the amount of laundry in the washing tub. With this configuration, it is possible to appropriately set the ratio of the strong whirling time period to the gentle whirling time period or the ratio of the strong whirling time period to the stationary time period in accordance with the volume of water or the amount of laundry, thereby mitigating damage to the cloth of the laundry and avoiding unnecessary power consumption.

According to the present invention, there is provided a washing machine in which "rinsing with water injection" is possible, the washing machine being constructed such that antibacterial metal ions can be added to supplied water during "rinsing with water injection". With this configuration, in the "rinsing with water injection", the concentration of metal ions in water does not decrease, and a necessary amount of metal ions are attached to the laundry.

According to the present invention, there is provided a washing machine in which antibacterial metal ions can be added to water within a predetermined operation in a laundry washing process, the washing machine being constructed such that, when uneven distribution of laundry is detected during a spinning rotation of a washing tub after metal ions are added, a different countermeasure can be taken fromwhen uneven distribution of laundry is detected while no metal ions are added. With this configuration, when uneven scattering of laundry is detected while rotation occurs for dehydration after metal ions are added, uneven scattering of laundry can be corrected in consideration of the antibacterial action of metal ions.

According to the present invention, in the washing machine constructed as described above, a different countermeasure is to perform rinsing for correcting uneven distribution of the laundry by agitating the laundry in water containing metal ions. With this configuration, in the case where the rinsing operation for correcting the uneven distribution of the laundry is performed using the replenished fresh water, since the fresh water also contains metal ions, the antibacterial action on the laundry is not weakened.

According to the present invention, in the washing machine constructed as described above, when the rinsing operation for correcting the uneven distribution of the laundry is performed using the replenished fresh water containing the metal ions, the amount of the metal ions to be added is smaller than the amount added in the previous operation. With this configuration, once the laundry is treated with the metal ions, it is not necessary to supply an excessive amount of the metal ions to the laundry, thereby limiting consumption of the metal ions.

According to the present invention, in the washing machine constructed as described above, a different countermeasure is to perform rinsing for correcting uneven distribution of laundry by agitating the laundry in water containing no metal ions while indicating and/or informing that the supplied water contains no metal ions. If the water used in the operation for correcting the uneven distribution of the laundry contains metal ions, the consumption of the metal will be faster than its designed service life, and thus the time when the metal ions cannot be obtained comes ahead. With this configuration, when the rinsing operation for correcting uneven distribution of laundry is performed with water containing no metal ions in order to limit consumption of metal ions, the actual situation is indicated and/or notified to the user, and the user can know that the intended antibacterial effect may not be obtained.

According to the present invention, in the washing machine constructed as described above, a different countermeasure is to terminate the spinning while indicating and/or informing that the uneven scattering of the laundry is detected. With this configuration, it is possible to expect the user to manually correct the unbalance by not performing the rinsing operation for correcting the uneven distribution of the laundry any more and by informing the user that the unbalance of the laundry has occurred. This will limit the consumption of metal ions while achieving the desired antimicrobial effect.

According to the present invention, in the washing machine constructed as described above, when it is detected that the unbalance of the laundry is not the only cause, different countermeasures are taken for various causes. If the imbalance is corrected for each reason with water containing metal ions, the metal that produces the metal ions is quickly depleted. With this configuration, it is possible to limit the loss of metal by correcting the unbalance without using water containing metal ions as one of the countermeasures.

According to the present invention, in the washing machine configured as described above, a plurality of countermeasures against unbalance are provided, and the type and/or order of countermeasures to be taken can be selected. With this configuration, it is possible for the user to autonomously select a countermeasure, such as preferentially maintaining a high antibacterial action by using a sufficient amount of metalions, or preferentially saving metal ions.

According to the present invention, in the washing machine constructed as described above, the metal ions are generated by using an ion elution device that elutes the metal ions by applying a voltage between the electrodes. With this configuration, the concentration of metal ions in water is easily adjusted by controlling the voltage, the current, or the application time of the voltage, and the laundry obtains a desired antibacterial effect.

Brief Description of Drawings

Fig. 1 is a vertical sectional view of a washing machine embodying the present invention.

FIG. 2 is a schematic vertical cross-sectional view of a water inlet nozzle.

FIG. 3 is a partial top view of the interior of a washing machine.

FIG. 4 is a top view of an ion elution device.

Fig. 5 is a vertical sectional view taken along line a-a of fig. 4.

Fig. 6 is a vertical sectional view taken along the line B-B in fig. 4.

FIG. 7 is a horizontal cross-sectional view of an ion elution device.

Fig. 8 is a perspective view of one electrode.

FIG. 9 is a circuit diagram of a driving circuit of an ion elution device.

Fig. 10 is a flowchart of the entire process of washing laundry.

FIG. 11 is a flow chart of a washing operation.

Fig. 12 is a flowchart of a rinsing operation.

FIG. 13 is a flow chart of a dewatering operation.

Fig. 14 is a flowchart of a final-rinsing operation.

Fig. 15 is a timing chart of a final-rinsing operation.

Fig. 16 is a timing chart of a rinsing operation for correcting uneven distribution of laundry.

PREFERRED EMBODIMENTS

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a vertical sectional view showing the overall configuration of a washing machine 1. The washing machine 1 is of an automatic type and has a cabinet 10. The box-shaped casing 10 is made of metal or synthetic resin and has openings at the top and bottom thereof. The top opening of the casing 10 is covered by a top plate 11, wherein the top plate 11 is made of synthetic resin and is fixed to the casing 10 by screws. In fig. 1, the front and rear of the washing machine 1 are directed to the left and right sides, respectively. The rear portion of the top surface of the top plate 11 is covered by a rear panel 12, wherein the rear panel 12 is made of synthetic resin and is fixed to the cabinet 10 or the top plate 11 with screws. The bottom opening of the casing 10 is covered by a base 13, wherein the base 13 is made of synthetic resin and is fixed to the casing 10 with screws. Any such screws are not shown in the drawings.

Legs 14a and 14b for supporting the cabinet 10 on the ground are provided at four corners of the base 13. The rear leg 14b is a fixing leg formed integrally with the base 13. The front legs 14a are height-adjustable screw legs, and rotating them can adjust the height of the washing machine 1.

The top plate 11 has a laundry inlet 15, through which laundry is placed in a washing tub described later, 15. The laundry inlet 15 is covered from above by a cover 16. The lid 16 is coupled to the top plate 11 by a hinge 17 so as to be pivotable in a vertical plane.

A tub 20 and a washing tub 30, which also serves as a dehydration tub, are provided inside the cabinet 10. The tub 20 and the washing tub 30 each have a cylindrical cup shape with an open top, and the two tubs are concentrically disposed while their axes are kept vertical, and the washing tub 30 is located inside the tub 20. The tub 20 is hung on the cabinet 10 by a hanging member 21. The suspension members 21 connect the lower outer surface of the tub 20 to the four inside corners of the cabinet 10, and support the tub 20 in such a manner that it can swing in a horizontal plane.

The washing tub 30 has a circumferential wall that widens slightly upward. The circumferential wall has a large number of drainage holes 31, which drainage holes 31 are made in a circular ring-shaped arrangement around the topmost part of the circumferential wall, and apart from the drainage holes, there are no openings allowing liquid to flow through. The washing tub 30 is of a so-called "holeless" type. An annular weight 32 is attached to the rim of the top opening of the washing tub 30 to suppress chattering generated by the washing tub 30 when the washing tub 30 is rotated at a high speed for dewatering laundry. Inside the washing tub 30, on the bottom surface thereof, there is provided an agitator 33 for generating a washing water flow or a rinsing water flow inside the washing tub 30.

The tub 20 has a driving device 40 mounted on a bottom surface thereof from below. The driving device 40 includes a motor 41, a clutch mechanism 42, and a brake mechanism 43, and has a spinning spindle 44 and a stirring spindle 45 projecting upward from the center thereof. The dehydrating shaft 44 and the stirring shaft 45 form a double shaft structure, with the stirring shaft 45 being located inside the dehydrating shaft 44. Both the spindles penetrate the tub 20. The spinning spindle 44 is then coupled to the washing tub 30 to support the washing tub 30. On the other hand, the agitating spindle 45 is further penetrated into the washing tub 30, and then is coupled to the agitator 33 so as to support the agitator 33. Sealing members for preventing water leakage are provided between the dehydrating spindle 44 and the tub 20 and between the dehydrating spindle 44 and the agitating spindle 45.

An electromagnetically driven water inlet valve 50 is provided inside a space below the rear panel 12. The inlet valve 50 has a connecting conduit 51, and the connecting conduit 51 extends upwardly through the rear panel 12. A water inlet hose (not shown) through which clean water such as tap water is supplied to the washing machine is connected to the connection pipe 51. The water inlet valve 50 supplies water to a water inlet nozzle 53 in the shape of a container, the water inlet nozzle 53 being positioned above the inside of the tub 20. The water inlet nozzle 53 has a structure as shown in fig. 2.

Fig. 2 is a schematic vertical sectional view of the water inlet nozzle 53. The water inlet mouth 53 has an opening at the front, and through the opening, a drawer 53a is inserted. The inside of the drawer 53a is divided into a plurality of regions (the present embodiment has two regions, that is, a left region and a right region). The left area is a detergent chamber 54 which serves as a storage space for detergent. The right area is a treating agent chamber 55 serving as a storage space for a treating agent for laundry washing. The detergent chamber 54 has a water outlet 54a at the bottom thereof, which is open toward the inside of the water inlet nipple 53. A siphon 57 is disposed in the treating agent chamber 55. The water inlet nozzle 53 has a water outlet 56 below the bottom of the drawer 53a, and water is supplied into the washing tub 30 through the water outlet 56.

The siphon tube 57 is composed of an inner tube 57a extending vertically upward from the bottom surface of the treating agent chamber 55 and a cap-shaped outer tube 57b covering the inner tube 57 a. Between the inner tube 57a and the outer tube 57ab, there is a gap that allows water to pass through. The inner tube 57a is open at the bottom thereof to the bottom of the water inlet tap 53. A predetermined gap is maintained between the bottom end of the outer tube 57b and the bottom surface of the treating agent chamber 55 so as to serve as a water inlet. When water is injected into the treating agent chamber 55 to a height higher than the top end of the inner tube 57a, the siphon principle is used such that the water flows out of the treating agent chamber 55 through the siphon tube 57 and then reaches the bottom of the water inlet nozzle 53, and then the water is injected into the washing tub 30 through the water outlet 56.

The feed valve 50 is composed of a main feed valve 50a and a sub feed valve 50 b. The primary inlet valve 50a allows a relatively large flow of water, while the secondary inlet valve 50b allows a relatively small flow of water. By making the internal structures of the main water inlet valve 50a and the sub water inlet valve 50b different from each other, or by making the internal structures of both valves the same but using them in combination with the flow restricting means having different throttling ratios, a larger or smaller flow is set. The connection conduit 51 is shared by the main water inlet valve 50a and the sub water inlet valve 50 b.

The main inlet valve 50a is connected to an opening in the top of the inlet nozzle 53 by means of a main inlet passage 52 a. The opening is open toward the detergent chamber 54 so that a large amount of water from the main water inlet valve 50a is injected into the detergent chamber 54 through the main water inlet passage 52 a. The secondary inlet valve50b is connected to an opening in the top of the inlet nozzle 53 by means of a secondary inlet passage 52 b. The opening is open toward the treating agent chamber 55 so that a small amount of water from the sub water feed valve 50b is fed into the treating agent chamber 55 through the sub water feed passage 52 b. That is, a passage extending from the main water inlet valve 50a to the washing tub 30 through the detergent chamber 54 is separated from a passage extending from the sub water inlet valve 50b to the washing tub 30 through the treating agent chamber 55.

Returning to fig. 1, a drain hose 60 is mounted on the bottom of the tub 20, and water is drained out of the tub 20 and the washing tub 30 through the drain hose 60. Water flows from the drain pipes 61 and 62 into the drain hose 60. The drain guide duct 61 is connected to an outermost peripheral portion of the bottom surface of the tub 20, and the drain guide duct 62 is connected to a most central portion of the bottom surface of the tub 20.

Inside the tub 20, on the bottom surface thereof, an annular partition wall 63 is fixed in such a manner as to surround a portion of the tub 20 to which the drain conduit 62 is connected. The partition wall 63 is provided at its top with an annular sealing member 64. The sealing member 64 is maintained in contact with a circumferential surface of a disc fixed to the bottom outer surface of the washing tub 30 to form an independent drainage space 66 between the tub 20 and the washing tub 30. The drain space 66 communicates with the inside of the washing tub 30 through a drain outlet 67 formed at the bottom of the washing tub 30.

The drain conduit 62 carries a solenoid actuated drain valve 68. In a part of the drain conduit 62, an air trap 69 is provided on the upstream side of the drain valve 68. A lead 70 extends from the air collector 69. The guide tube 70 is connected at its top endto a water level switch 71.

A controller 80 is provided in the front of the cabinet 10 below the top plate 11. The controller 80 receives an instruction from a user via an operation/display panel 81 located on the top surface of the top plate 11 and sends an operation instruction to the driving device 40, the water inlet valve 50, and the drain valve 68. The controller 80 also sends a display instruction to the operation/display panel 81. The controller 80 includes a drive circuit for driving the ion elution device described later.

How the washing machine 1 operates will be described below. First, the cover 16 is opened, and laundry is placed in the washing tub 30 through the laundry inlet 15. The drawer 53a is pulled out from the inlet nozzle 53 and a detergent is placed in a detergent chamber 54 in the drawer 53 a. A treatment agent (softener) is disposed in the treatment agent chamber 55. The treatment agent (softener) may be introduced at an intermediate point in the laundry washing process, or may not be introduced when it is not necessary. After the detergent and treatment (softener) are put in, the drawer 53a is pushed back into the water nozzle 53.

After the detergent and the treatment agent (softener) for addition are prepared in this way, the cover 16 is closed, and a desired laundry course is selected by operating the operation button group located on the operation/display panel 81. By subsequently pressing the start button, the laundry washing process is performed according to the flowcharts shown in fig. 10 to 13.

Fig. 10 is a flowchart showing the entire process of washing the laundry. In step S201, a laundry washing operation is started at a preset timing. It is detected whether a timer start operation is selected. If the timer start operation is selected, the flow advances to step S206; otherwise, the flow advances to step S202.

In step S206, it is detected whether or not the operation start time has been reached. If the operation start time has been reached, the flow advances to step S202.

In step S202, it is detected whether the washing operation is selected. If the washing operation is selected, the flow advances to step S300. How the washing operation in step S300 is performed will be described later with reference to a flowchart shown in fig. 11. At the end of the washing operation, the flow advances to step S203. If the washing operation is not selected, the flow proceeds directly from step S202 to step S203.

In step S203, it is detected whether the rinsing operation is selected. If the rinsing operation is selected, the flow advances to step S400. How the rinsing operation in step S400 is performed will be described later with reference to a flowchart shown in fig. 12. In fig. 10, the rinsing operation is repeated three times, and the respective steps in the operation are denoted by step numbers plus a numerical suffix, such as "S400-1", "S400-2", and "S400-3". The number of rinsing operations is set by the user himself. In the present embodiment, "S400-3" is the final rinsing operation.

At the end of the rinsing operation, the flow advances to step S204. If the rinsing operation is not selected, the flow proceeds directly from step S203 to step S204.

In step S204, it is detected whether the dehydration operation is selected. If the dehydration operation is selected, the flow advances to step S500. How the dehydration operation in step S500 is performed will be described later with reference to the flowchart shown in fig. 13. At the end of the dehydration operation, the flow advances to step S205. If the dehydration operation is not selected, the flow proceeds directly from step S204 to step S205.

In step S205, the controller 80 terminates the operation, particularly, the processing unit (microcomputer) therein, automatically executing according to a predetermined program. Further, the end of the laundry washing course is indicated by sounding an operation end beep. At the end of all operations, the washing machine 1 returns to a standby state, ready for a new laundry washing process.

Next, referring to fig. 11 to 13, the independent operations of washing, rinsing, and dehydrating will be described.

Fig. 11 is a flowchart of the washing operation. In step S301, monitoring of the sensed water level in the washing tub 30 by the water level switch 71 is started. In step S302, it is detected whether the laundry amount sensing operation is selected. If the laundry amount sensing operation is selected, the flow advances to step S308; otherwise, the flow proceeds directly from step S302 to step S303.

In step S308, the amount of laundry is measured based on the rotational load of the pulsator 33. At the end of the laundry amount sensing operation, the flow advances to step S303.

In step S303, the main water inlet valve 50a is opened, and water is injected into the washing tub 30 through the water inlet nozzle 53. Since the main water inlet valve 50a is set for a large flow of water, water quickly fills the washing tub 30. The detergent placed in the detergent chamber 54 is completely washed away by the large water flow and mixed therewith, entering the washing tub 30. The drain valve 68 remains closed. When the level switch 71 detects a set water level, the main water inlet valve 50a is closed. Subsequently, the flow advances to step S304.

In step S304, a preparatory operation is performed. The pulsator 33 is repeatedly rotated in forward and reverse directions to agitate the laundry and the water, thereby completely immersing the laundry in the water. This allows the garment to absorb a sufficient amount of water and allows air trapped in many parts of the garment to escape. As a result of the preliminary operation, if the water level detected by the water level switch 71 becomes lower than the initial time, the main water inlet valve 50a is opened to supply some water to be restored to the set water level in step S305.

If a laundry course including 'cloth type sensing' is selected, the cloth type is sensed when the preliminary operation is performed. At the end of the preparation operation, a change in the water level from the set water level is detected, and if the water level drops more than a predetermined amount, the laundry is judged to be of the high-absorption cloth type.

In step S305, when the set water level is stable, the flow advances to step S306. According to the user's setting, the motor 41 rotates the pulsator 33 in a predetermined pattern so as to generate a main water current for washing in the washing tub 30. With this main water flow, the laundry is washed. The spinning spindle 44 is kept braked by the brake mechanism 43 so that the washing tub 30 is not rotated even when the washing water and the laundry are moved.

At the end of the process in which the laundry is washed with the main water flow, the flow proceeds to step S307. In step S307, the agitator 33 is repeatedly rotated in the forward and reverse directions at short intervals. This allows the laundry to be loosened, and thus allows the laundry to be uniformly dispersed in the washing tub 30. This is done for the purpose of preparing for the dehydrating rotation of the washing tub 30.

Next, with reference to a flowchart shown in fig. 12, a rinsing operation will be described. First, in step S500, a dehydration operation is performed, and a description of the dehydration operation will be given later with reference to a flowchart shown in fig. 13. At theend of the dehydration operation, the flow advances to step S401. In step S401, the main water inlet valve 50a is opened, and the supplied water reaches a set water level.

When the water supply is ended, the flow advances to step S402. In step S402, a preparatory operation is performed. In the course of performing the predetermined operation in step S402, the laundry adhered to the washing tub 30 is loosened and immersed in water in step S500 (dehydration operation), so that the laundry sufficiently absorbs water.

At the end of the predetermined operation, the flow advances to step S403. As a result of the preliminary operation, if the water level detected by the water level switch 71 becomes lower than the initial time, the main water inlet valve 50a is opened to supply some water to be restored to the set water level.

After the set water level is restored in step S403, the flow advances to step S404. According to the user's setting, the motor 41 rotates the pulsator 33 in a predetermined pattern so as to generate a main water flow for rinsing in the washing tub 30. With this main water flow, the laundry is rinsed. The spinning spindle 44 is kept braked by the brake mechanism 43 so that the washing tub 30 is not rotated even when the rinsing water and the laundry are moved.

At the end of the process in which the laundry is rinsed with the main water flow, the flow advances to step S406. In step S406, the agitator 33 is repeatedly rotated in the forward and reverse directions at short time intervals. This allows the laundry to be loosened, and thus allows the laundry to be uniformly dispersed in the washing tub 30. This is done for the purpose of preparing for dewatering rotation.

In the foregoing description, it is assumed that the rinsing operation is performed using the rinsing water stored in the washing tub30. This operation is called "rinsing with stored water". However, it is also possible to always perform the rinsing operation by supplementing fresh water, which is called "rinsing with water supply", or to perform the rinsing operation by using water always supplied from the water inlet nozzle 53 while the washing tub 30 is rotated at a low speed, which is called "spray rinsing".

In the final-rinsing operation, steps different from those described above are performed. This will be described in detail later.

Next, with reference to a flowchart shown in fig. 13, the dehydration operation will be described. First, in step S501, the drain valve 68 is opened. The washing water in the washing tub 30 is drained through the drain space 66. During the dewatering operation, the drain valve 68 is kept open.

After most of the washing water has been discharged from the laundry, the clutch mechanism 42 and the brake mechanism 43 are switched. The timing for switching the clutch mechanism 42 and the brake mechanism 43 is either before or simultaneously with the start of the drain operation. The motor 41 now rotates the dewatering spindle 44. This causes the washing tub 30 to start the spinning. The pulsator 33 rotates together with the washing tub 30.

When the washing tub 30 is rotated at a high speed, the laundry is pressed against the inner circumferential wall of the washing tub 30 by a centrifugal force. The washing water present in the laundry is also collected on the inner surface of the circumferential wall of the washing tub 30, and since the washing tub 30 is slightly widened upward as described earlier, the washing water subjected to the centrifugal force is raised along the inner surface of the washing tub 30. When the washing water reaches the top end of the washing tub 30, it is discharged through the drain hole 31. The wash water, which has flowed out of the drain hole 31, may hit the inner surface of the tub 20 and then flow down along the inner surface of the tub 20 to the bottom of the tub 20. Subsequently, the washing water is discharged out of the cabinet 10 through the drain duct 61 and the drain hose 60.

In the flowchart shown in fig. 13, after the dehydration operation is performed at a relatively low speed in step S502, the dehydration operation is performed at a relatively high speed in step S503. At the end of step S503, the flow advances to step S504. In step S504, the supply of electric power to the motor 41 is stopped, and a termination operation is performed so as to stop.

The washing machine 1 is equipped with an ion elution device 100. The ion elution device 100 is connected to the downstream side of the main water inlet conduit 52 a. Next, referring to fig. 3 to 9, the structure and function of the ion elution device 100 and the purpose of incorporating it into the washing machine 1 will be described.

Fig. 3 is a partial top view showing the layout of the ion elution device 100 and the water inlet nozzle 53. The ion elution unit 100 is directly connected to the main water inlet valve 50a and the water inlet nozzle 53 on both ends. In other words, the ion elution device 100 alone constitutes the entire main water inlet passage 52 a. The sub water inlet passage 52b is constructed by connecting a pipe protruding from the water inlet nozzle 53 to the sub water inlet valve 50b by a hose. In the schematic view of fig. 1, the water inlet valve 50, the ion elution unit 100, and the water inlet nozzle 53 are aligned with the front-rear axis of the washing machine 1. However, in the actual washing machine, they are not arranged as such, but are arranged in a straight line along the left-right axis of the washing machine 1.

Fig. 4 to 8 show the structure of the ion elution device. Fig. 4 is a top view. Fig. 5 is a verticalsectional view taken along line a-a of fig. 4. Fig. 6 is a vertical cross-sectional view taken along line B-B of fig. 4. Fig. 7 is a horizontal sectional view. Fig. 8 is a perspective view of one electrode.

The ion elution device 100 has a housing 110 made of transparent or translucent, colorless or colored synthetic resin or opaque synthetic resin. The housing 110 is composed of a housing main body 110a and a cover 110b, wherein the housing main body 110a has an opening at the top thereof, and the cover 110b closes the opening at the top plate (see fig. 5). The housing 110 is formed to be long and narrow, and includes an inlet port 111 at one longitudinal end and an outlet port 112 at the other end. The water inlet 111 and the water outlet 112 are both in the shape of a duct. The cross-sectional area of the water outlet 112 is smaller than the cross-sectional area of the water inlet 111.

The housing 110 is disposed in a horizontal state in its longitudinal direction. The housing main body 110a horizontally arranged in this manner has a bottom portion gradually inclined toward the water outlet 112 (see fig. 5). In other words, the water outlet 112 is located at the lowest height in the inner space of the housing 110.

The cover 110b is fixed to the housing main body 110a with four screws 170 (see fig. 4). A sealing ring 171 is interposed between the housing main body 110a and the cover 110b (see fig. 5).

Inside the housing 110, two plate-shaped electrodes 113 and 114 are provided so as to be parallel to the flow of water flowing from the water inlet 111 toward the water outlet 112 and face each other. When a predetermined voltage is applied to the electrodes 113 and 114 under the condition that the casing 110 is filled with water, metal ions in the metal forming the electrodes 113 and 114 are immediately eluted from the electrode on the anode side. For example, the electrodes 113 and 114 may be configured such that silver plates each of 2 cm × 5 cm and having a thickness of about 1 mm are arranged spaced apart from each other by 5 mm.

The material in the electrodes 113 and 114 is not limited to silver. Any metal may be used as long as it is a source material for antibacterial metal ions. In addition to silver, copper, silver-copper alloy, zinc or similar materials may be selected. The silver ions eluted from the silver electrode, the copper ions eluted from the copper electrode and the zinc ions eluted from the zinc electrode all show excellent disinfection effect, even on mold. Silver ions and copper ions can be eluted simultaneously by using the silver-copper alloy.

Whether or not to perform elution can be selected by whether or not to apply a voltage to the ion elution device 100. Further, the elution amount of the metal ions can be controlled by controlling the current and the voltage application time. Compared with a method of eluting metal ions by using zeolite or other metal ion carriers, it is convenient because whether to add metal ions or not can be electrically selected and the concentration of metal ions can be electrically adjusted.

The electrodes 113 and 114 are not arranged perfectly parallel. In plan view, they are disposed obliquely with the gap therebetween being gradually narrowed from upstream toward downstream along the flow of water flowing through the inside of the housing 110, in other words, from the water inlet 111 toward the water outlet 112 (see fig. 7).

The plan view shape of the housing main body 110a is also narrowed from the end having the water inlet 111 toward the other end having the water outlet 112. That is, the cross-sectional area in the inner space of the casing 110 gradually decreases from the upstream side toward the downstream side.

The electrodes 113 and 114 each have a rectangular outline, and are provided thereon with terminals 115 and 116, respectively. The terminals 115 and 116 are provided at the edge inner portions of the electrodes 113 and 114 on the upstream side, overhanging from the lower side edges of the electrodes 113 and 114, respectively.

The electrode 113 and the terminal 115 are integrally made of the same metal, and the electrode 114 and the terminal 116 are also integrally made of the same metal. The terminals 115 and 116 are open to the bottom of the housing main body 110a through holes formed in the bottom wall of the housing main body 110 a. Where the terminals 115 and 116 protrude out of the housing 110a, as shown in an enlarged view in fig. 6, a waterproof seal 172 is installed. The waterproof seal 172 forms a double seal configuration together with a second sleeve 175 described later to prevent water from leaking from the portion.

At the bottom of the housing 110a, an insulating wall 173 is integrally formed, which insulates the terminals 115 and 116 (see fig. 6). Terminals 115 and 116 are connected to a drive circuit within controller 80 by means of cables (not shown).

The portions of the terminals 115 and 116 located in the housing 110 are protected by a sleeve made of an insulating material. Two types of sleeves are used. A sleeve 174 is made of synthetic resin and is fitted over the root portions of the terminals 115 and 116. A portion of the first sleeve 174 is extended to one side of the electrodes 113 and 114, protrusions are formed on the side surfaces of these portions, and the protrusions are engaged on through holes formed in the electrodes 113 and 114. This helps prevent the electrodes 113 and 114 from disengaging the sleeve 174. The second sleeve 175 is made of soft rubber, and fills the gap between the first sleeve 174 and the bottom wall of the housing main body 110a, thereby preventing water from leaking through the gap between the second sleeve 175 and the housing main body 110a and through the gap between the second sleeve 175 and the electrodes 113 and 114.

As described previously, the terminals 115 and 116 are located on the upstream side of the electrodes 113 and 114. The upstream sides of the electrodes 113 and 114 are supported by a first sleeve 174, wherein the first sleeve 174 is engaged over the terminals 115 and 116. On the inner surface of the cap 110b, a fork-shaped support 176 is formed to be fitted to a position where the first sleeve 174 is located (see fig. 6). The support 176 catches the upper side edge of the first sleeve 174, and becomes a rigid support together with the second sleeve 175 filled in the gap between the first sleeve 174 and the housing main body 110 a. The fork-shaped support 176 grips the electrodes 113 and 114 with fingers of different lengths, whereby the electrodes 113 and 114 can be kept at a proper distance from each other on the side of the cover 110 b.

The downstream sides of the electrodes 113 and 114 are also supported by supports formed on the inner surface of the casing 110. A fork-shaped support 177 protrudes from the bottom surface of the housing main body 110 a. Also, a fork-shaped support 178 depends from the top plate of the cover 110b, facing the support 177 (see fig. 5 and 8). The electrodes 113 and 114 are held by the supports 177 and 178 at the lower and upper edges of the downstream side, respectively, so as not to move.

As shown in fig. 7, the electrodes 113 and 114 are disposed as surface-opposing surfaces, and face each other with a gap from the inner surface of the housing 110. Further, as shown in fig. 5, the electrodes 113 and 114 are disposed so as to maintain a gap (except for the portions that come into contact with the supports 176, 177, and 178) between their upper and lower side edges and the inner surface of the housing 110. Further, as shown in fig. 7 or fig. 5, a gap is formed between the upstream and downstream side edges of the electrodes 113 and 114 and the inner surface of the casing 110.

When it is necessary to make the width of the case 110 significantly smaller, the electrodes 113 and 114 may be configured in such a manner that the surfaces facing each other are firmly attached to the inner wall of the case 110.

In order to prevent impurities from coming into contact with the electrodes 113 and 114, a metal mesh filter is installed on the upstream side of the electrodes 113 and 114. As shown in fig. 2, a filter 180 is disposed in the connecting conduit 51. The filter 180 serves to prevent intrusion of foreign substances into the inflow valve 50 and also serves as an upstream filter of the ion elution device 100.

A wire mesh filter 181 is installed at the downstream side of the electrodes 113 and 114. The filter 181 prevents fragments of the electrodes 113 and 114 from flowing out when the electrodes are thinned and broken due to long-term use. For example, the water outlet 112 may be selected as a location for installing the filter 181.

The positions of the filters 180 and 181 are not limited to the aforementioned positions. They may be provided at any position in the water inlet passage as long as the condition of being installed on the "upstream side of the electrode" and the "downstream side of the electrode" is satisfied. Filters 180 and 181 are removable to allow removal of impurities they capture or to remove materials that cause clogging.

Fig. 9 shows a drive circuit 120 for the ion elution device 100. A transformer 122 is connected to commercial distributed electric power 121 to reduce 100V to a predetermined voltage. The output voltage of the transformer 122 is rectified by a full-wave rectifying circuit 123 and then converted into a constant voltage by a constant voltage circuit 124. A constant current circuit 125 is connected to the constant voltage circuit 124. The constant current circuit 125 operates in such a manner that a constant current is supplied to the electrode driving circuit 150 described later without being affected by a resistance change in the electrode driving circuit 150.

A rectifier diode 126 is connected in parallel to the transformer 122 and to the commercial power 121. The output voltage of the rectifying diode 126 is smoothed by a capacitor 127, then converted into a constant voltage by a constant voltage circuit 128, and then supplied to a microcomputer 130. The microcomputer 130 controls the activation of a triac 129 connected between one end of the primary winding of the transformer 122 and the commercial power 121.

The electrode driving circuit 150 is composed of NPN transistors Q1 to Q4, diodes D1 and D2, and resistors R1 to R7. These elements are interconnected as shown in the figures. Transistor Q1 and diode D1 form a photo-coupler 151, while transistor Q2 and diode D2 form a photo-coupler 152. The diodes D1 and D2 are photodiodes, while the transistors Q1 and Q2 are phototransistors.

The microcomputer 130 supplies a high level voltage to the line L1 and a low level voltage (or zero voltage, that is, off) to the line L2. Diode D2 is then turned on, and this will turn on transistor Q2. When the transistor Q2 is turned on, current flows through the resistors R3, R4 and R7, and this causes a bias voltage to be applied to the base of the transistor Q3. Thereby, the transistor Q3 is turned on.

On the other hand, the diode D1 is turned off, and thereby the transistor Q1 is turned off, and accordingly, the transistor Q4 is turned off. In this state, a current flows from the anode-side electrode 113 to the cathode-side electrode 114. Finally, in the ion elution device 100, metal ions are generated as positively charged ions and negatively charged ions.

When a current flows through the ion elution device 100 in one direction for a long time, the electrode 113 located on the anode side in fig. 9 is worn away, while the electrode 114 located on the cathode side collects impurities in the water in the form of scale deposited thereon. This may degrade the performance of the ion elution device 100. To avoid this, the electrode driving circuit 150 may be operated in a forced electrode cleaning mode.

In the forcible electrode cleaning mode, the microcomputer 130 switches the control mode so as to reverse the voltage applied between the lines L1 and L2 and thereby change the current flowing between the electrodes 113 and 114. In this mode, transistors Q1 and Q4 are operating, while transistors Q2 and Q3 are off. The microcomputer 130 has a counting capability and switches the control mode as described above each time a predetermined number is reached.

When the resistance in the electrode drive circuit 150, particularly the resistance of the electrodes 113 and 114, changes and thus, for example, the current flowing between the electrodes decreases, the constant current circuit 125 increases its output voltage to compensate for the decrease. However, as the total usage time increases, the ion elution device 100 eventually reaches the end of its useful life. When this occurs, even if the control mode is switched to the forcible electrode cleaning mode, or even if the output voltage of the constant current circuit 125 rises, the decrease in the current is not compensated for any more.

To address this, in the circuitry discussed below, the current flowing between electrodes 113 and 114 in ion elution device 100 is monitored based on the voltage across resistor R7. When the current becomes equal toa predetermined minimum current, a current detection circuit 160 detects it. In practice, the minimum current that has been detected is transmitted from the photodiode D3 to the microcomputer 130 through a phototransistor Q5, wherein the photodiode D3 is part of the photocoupler 163. The microcomputer 130 then drives a warning indicator 131 by means of a line L3 to indicate a predetermined warning. The warning indicator 131 is provided in the operation/display panel 81 or the controller 80.

In addition, in order to cope with the occurrence of a failure such as a short circuit within the electrode driving circuit 150, a current detecting circuit 161 is provided for detecting whether or not the current is larger than a predetermined maximum current. Based on this current detection circuit 161, the microcomputer 130 drives the warning indicator 131. Also, when the output voltage of the constant current circuit 125 becomes lower than a preset minimum voltage, a voltage detection circuit 162 detects this, and the microcomputer 130 drives the warning indicator 131 similarly.

The metal ions generated by the ion elution device 100 are injected into the washing tub in the following manner.

In the final-rinse operation, metal ions and a softener to be used as a treatment agent are added. Fig. 14 is a flowchart showing the final-rinsing operation. In the final rinsing operation, after the dehydrating operation in step S500, the flow proceeds to step S420. In step S420, it is detected whether a treatment substance addition operation is selected. When "treating agent addition" is selected by performing a selection operation by means of the operation/display panel 81, the flow proceeds to step S421. Otherwise, the flow advances to step S401 in fig. 12, and the final rinsing operation is performed in the same manner as the previous rinsing operation.

In step S421, it is detected whether the treatment material to be added is of two types, i.e., metal ions and a softener. When "metal ions and the softener" are selected by performing the selection operation by means of the operation/display panel 81, the flow advances to step S422; otherwise, the flow advances to step S426.

In step S422, the main water inlet valve 50a and the sub water inlet valve 50b are opened, and water flows into the main water inlet passage 52a and the sub water inlet passage 52 b.

Step S422 is a process for eluting metal ions. A predetermined amount of water flows, filling the internal space of the ion elution device 100, wherein the predetermined amount is set to be larger than the volume of water set for the sub water inlet valve 50 b. At the same time, the drive circuit 120 applies a voltage between the electrodes 113 and 114, causing the ions of the metals that form them to be eluted into the water. When the metal forming the electrodes 113 and 114 is silver, this occurs on the anode side And silver ion Ag⁺Is eluted into water. The current flowing between the electrodes 113 and 114 is direct current. The water added with the metal ions flows into the detergent chamber 54 and is then injected into the washing tub 30 from the water outlet 54a through the water outlet 56.

From the sub water inlet valve 50b, less water flows out than from the main water inlet valve 50a, and is injected into the detergent chamber 55 through the sub water inlet passage 52 b. If a treating agent (conditioner) has been supplied into the treating agent chamber 55, the treating agent (conditioner) is supplied into the washing tub 30 together with water through the siphon 57. This addition is performed simultaneously with the addition of the metal ions. Until the water level in the treating agent chamber 55 reaches a predetermined level, no siphoning action occurs. This allows the liquid treatment agent (conditioner) to be held in the treatment agent chamber 55 until such time as water is injected into the treatment agent chamber 55.

When a predetermined amount of water (equal to or more than an amount that causes a siphon action in the siphon tube 57) is injected into the treating agent chamber 55, the sub water inlet valve 50b is closed. The water-in step, that is, the step of adding a treating agent, is automatically performed regardless of whether the treating agent (softener) has been poured into the treating agent chamber 55, as long as "treating agent addition" is selected.

When a predetermined amount of water containing metal ions has been injected into the washing tub 30 and it is expected that the concentration of metal ions in the rinsing water will reach a predetermined value when water not containing metal ions is supplied to a set water level, the application of voltage between the electrodes 113 and 114 is stopped. After the ion elution device 100 stops generating the metal ions, the main water inlet valve 50a continues supplying water, and stops the supply of water when the water level in the washing tub 30 reaches a set height.

As previously described, in step S422, the metal ions and the treatment agent (softener) are added simultaneously. However, this does not necessarily mean that the time period for injecting the treatment agent (softener) into the washing tub by the siphon action completely overlaps with the time period for generating the metal ions by the ion elution device 100. Any of the foregoing time periods may be advanced or retarded. After the ion elution device 100 stops generating the metal ions, and while additionally supplying water containing no metal ions, a treatment agent (softener) may be added. It is sufficient that the metal ion adding operation and the treating agent (softener) adding operation areperformed separately in one order.

As previously described, the terminal 115 is integrally formed with the electrode 113 from the same metal, and the terminal 116 is also integrally formed with the electrode 114 from the same metal. Therefore, unlike the case of connecting different metals, a potential difference does not occur between the electrode and the terminal, thereby preventing the corrosion phenomenon from occurring. Furthermore, the integral formation simplifies the manufacturing process.

The gap between the electrodes 113 and 114 is set to be tapered, narrowing gradually from the upstream side toward the downstream side. This makes the electrodes 113 and 114 conform to the flow of water, and the electrodes 113 and 114 are less likely to generate chatter, whereby even if they are worn and thinned, they are still difficult to be chipped. Furthermore, excessive deformation that could cause shorting of the electrodes need not be considered.

The electrodes 113 and 114 are supported in such a manner that a gap is formed between them and the inner surface of the case 110. This helps prevent a metal layer from growing from the electrodes 113 and 114 to the inner surface of the housing 110 and causing a short circuit to occur therebetween.

Although terminals 115 and 116 are integrally formed with electrodes 113 and 114, respectively, electrodes 113 and 114 may still eventually be depleted from use. However, terminals 115 and 116 must remain unspent. In one embodiment of the present invention, the portion of the terminals 115 and 116 located inside the housing 110 is protected by sleeves 174 and 175 made of an insulating material and prevented from being depleted due to conduction. This helps prevent situations such as the terminals 115 and 116 breaking during use.

In the electrodes 113 and 114, portions where the terminals 115 and 116 are formed are located deep inside from the upstream side edge. The electrodes 113 and 114 are worn out, starting from the portion where the gap between them is narrowed. In general, the depletion phenomenon occurs at the edge portion. Although the terminals 115 and 116 are located on the upstream side of the resistors 113 and 114, they are not located entirely at the edges, but are located deep inside from the edges. Therefore, there is no fear that the depletion phenomenon starting at the edge of the electrode reaches the terminal to cause the terminal to be broken at the root thereof.

The electrodes 113 and 114 are supported on their upstream sides by the first sleeve 174 and the support 176. On the other hand, the downstream sides of the electrodes 113 and 114 are supported by the supports 177 and 178. Since they are rigidly supported on the upstream side and the downstream side in the manner described, the electrodes 113 and 114 do not suffer from chattering despite being in the water flow. Eventually, the electrodes 113 and 114 are not broken by the chattering.

The terminals 115 and 116 project downward through the bottom wall of the housing main body 110 a. Therefore, although the outer surface of the outer shell 110 is subjected to dew condensation due to contact of steam with the outer shell 110a (when warm water in a tub is used for washing operation, steam is liable to intrude into the inside of the washing machine 1) or due to temperature drop of the outer shell 110 due to water feeding, water from the dew condensation flows down along the cables connected to the terminals 115 and 116 and does not stay at the boundary between the terminals 115 and 116 and the outer shell 110. Therefore, a short circuit between the terminals 115 and 116 due to water generated by condensation of dew does not occur. The longitudinal direction of the case main body 110a is disposed on a horizontal line, which is easy to make it configured in such a manner that the terminals 115 and 116 formed on the sides of the electrodes 113 and 114 protrude downward through the bottom wall of the case main body 110 a.

The water outlet 112 of the ion elution device 100 has a smaller cross-sectional area than the water inlet 111 and has a greater water flow resistance than the water inlet 111. This allows water entering the interior of the housing 110 through the water inlet 111 to fill the interior of the housing 110 without causing stagnant air and completely submerge the electrodes 113 and 114. Thus, there does not occur a situation where, for example, the electrodes 113 and 114 have some portions that are not involved in generating metal ions but remain unmelted.

Not only the cross-sectional area of the water outlet 112 is smaller than that of the water inlet 111, but also the cross-sectional area of the inner space of the housing 110 is gradually reduced from the upstream side toward the downstream side. This reduces the generation of turbulence or bubbles inside the housing 110, thereby making the water flow smooth. Also, this prevents the electrodes from being locally unmelted due to the presence of the gas bubbles. The metal ions rapidly leave the electrodes 113 and 114 and are no longer returned to the electrodes 113 and 114, thereby enhancing the ion elution efficiency.

The ion elution device 100 is disposed in the main water inlet passage 52a for a large water flow where a large amount of water flows. This allows metal ions to be rapidly released from the housing 110 and prevented from returning to the electrodes 113 and 114, thereby enhancing the ion elution efficiency.

The water outlet 112 is provided at the lowest level in the inner space of the housing 110. Thus, when the supply of water to the ion elution device 100 is stopped, all of the water in the ion elution device100 flows out through the water outlet 112. Therefore, situations such as solidification of water remaining in the housing 110 upon cooling and malfunction or breakage of the ion elution device 100 do not occur.

A filter 180 is disposed on the upstream side of the electrodes 113 and 114. This makes it possible to cause solid impurities to be trapped by the filter 180 despite the presence of these impurities in the water supplied to the ion elution device 100, thus preventing these impurities from reaching the electrodes 113 and 114. Therefore, the impurities do not damage the electrodes 113 and 114 nor cause a short circuit between the electrodes, which would otherwise generate an excessive current or cause insufficient generation of metal ions.

A filter 181 is disposed on the downstream side of the electrodes 113 and 114. If the electrodes 113 and 114 are exhausted, become fragile due to long-term use, short-circuit into fragments, and the fragments flow, the filter 181 catches the fragments so as to prevent them from flowing downstream therefrom. Thus, the fragments of the electrodes 113 and 114 do not damage the object on the downstream side.

As an embodiment of the present invention, when the washing machine 1 is equipped with the ion elution device 100, if there is no filter 180 and 181, there is a possibility that impurities or electrode fragments may be attached to the laundry. The foreign substances or the electrode fragments may damage or injure the laundry, and if the laundry to which the foreign substances or the electrode fragments are attached is subjected to dehydration and drying, a person wearing the laundry may contact the foreign substances or the electrode fragments and feel uncomfortable or, worse, be injured. However, installing filters 180 and 181 may avoid this situation.

Neither of the filters 180 and 181 is necessarily provided. Either or both may beeliminated when it is believed that there is no problem with not installing the filter.

Returning to fig. 14, in step S423, the rinse water to which the metal ions and the treatment agent (softener) are added is stirred with a strong water flow (strong whirling), and thereby the laundry is brought into contact with the metal ions and the treatment agent (softener) is made to adhere to the laundry.

By sufficiently stirring with a strong whirling, the metal ions and the treatment agent (softener) can be uniformly dispersed in water and scattered in various corners of the laundry. After the stirring by the strong swirl is continued for the predetermined time, the flow proceeds to step S424.

In step S424, the situation is completely changed. The stirring operation is performed with a weak water flow (gentle swirling). The purpose of which is to allow the metal ions attached to the surface of the garment to exert their effect. As long as there is a flow of water, the user does not erroneously believe that the working process of the washing machine 1 has ended, although milder. Therefore, the stirring operation is performed gently. However, if there is a method for making the user recognize that the rinsing operation is still being performed, for example, by displaying an indication on the operation/display panel 81 to draw the user's attention, it is also permissible to stop the agitation and to make the water remain still.

After the gentle spinning operation, the flow proceeds to step S425, where the gentle spinning operation is set to be sufficient for the laundry to absorb the metal ions. At this time, the strong water flow (strong whirling) is again used to ensure that stirring is performed. This helps to disperse the metal ions to the portion of the laundry where the metal ions are not scattered and to make them firmly attached.

After step S425, the flow advances to step S406. In step S406, the agitator 33 is repeatedly rotated in the forward and reverse directions at short time intervals. This allows the laundry to be loosened, and thus allows the laundry to be uniformly scattered in the washing tub 30. The purpose of this is to prepare for the dewatering rotation.

Fig. 15 is a timing chart showing the performance of each constituent element from step S422 to step S406.

An example is given to show the time allocation of the various steps: for step S423 (power spin) four minutes; fifteen seconds four minutes for step S424 (gentle swirl); five seconds for step S425 (power spin); one minute and forty seconds for step S406 (uniform scattering of laundry). The total time from step S423 to step S406 is ten minutes. The gentle spinning time period may be replaced with a static time period.

When "rinsing with water injection" is selected, the time for step S425 (strong swirling) is extended from five seconds to one minute, and the main water inlet valve 50a is opened to supply water as shown with a one-dot chain line. At this time, the time for step S406 (uniform scattering of laundry) is forty-five seconds.

When the swirl is generated, the motor 41 periodically repeats start-up (normal rotation), shut-down, start-up (reverse rotation), and shut-down. The ratio of the on time to the off time varies according to the volume of water and/or the amount of laundry. For example, the time ratio (on/off) during operation at rated load is as follows: (the unit is second)

Step S423 (Strong rotation) 1.9/0.7

Step S424 (gentle rotation) 0.6/10.0

Step S425 (Strong rotation) 1.4/1.0

Step S406 (clothes uniformly spread) 0.9/0.4

In the case where the metal ions are added in the final rinse + operation, the total time of the operation becomes longer than the case where the metal ions are not added. The foregoing process is elaborated since the metal ions take a certain time to sufficiently adhere to the laundry. Thereby, the metal ions can be sufficiently attached to the laundry and exert the intended sterilization effect.

Although the volume of water and/or the amount of laundry inside the washing tub 30 are varied, the time distribution for the step S423 (strong spinning) and the time distribution for the step S424 (gentle spinning) may be set to be constant. This makes the control programming simple.

The time distribution for the step S423 (strong spinning) and the time distribution for the step S424 (gentle spinning) may be varied according to the volume of water and/or the amount of laundry inside the washing tub 30. This enables setting of the ratio of the strong spinning time period to the gentle spinning time period in accordance with the volume of water and the amount of laundry, thereby mitigating damage to the laundry and preventing unnecessary consumption of electric power.

Basically, it is preferable to add the metal ion and the treatment agent (softener) separately. This is because when metal ions come into contact with ingredients in the conditioner, they become compounds, thereby losing the antimicrobial effect of the metal ions. However, a small amount of metal ions remain in the rinsing water until the rinsing operation is finished. Also, the loss of action of the metal ions can be compensated by appropriately setting the concentration of the metal ions. Thus, by adding the metal ions and the treating agent (softener) at the same time, the rinsing time is shortened as compared with the case where the metal ions and the treating agent (softener) are separately added for the independentrinsing operation, and the household efficiency is improved although the antibacterial efficacy is slightly lowered.

Although the metal ions and the treatment agent (softener) inevitably meet in the washing tub 30, it is desirable to prevent them from contacting each other until they enter the washing tub 30. In one embodiment of the present invention, metal ions are added to the washing tub 30 from the main water inlet passage 52a through the detergent chamber 54. A treatment agent (softener) is added from the treatment agent chamber 55 to the washing tub 30. Since the passage for adding metal ions to the rinse water is thus separated from the passage for adding the treating agent to the rinse water, the metal ions and the treating agent (softener) do not come into contact with each other until they meet in the elution tank 30. Therefore, the metal ions do not become compounds due to contact with high concentrations of the treating agent (softener) and lose their antibacterial effect.

In the present description, it is assumed that the final-rinse operation is performed using rinse water stored in the wash tub 30. However, it is also possible to perform the final-rinsing operation with water injection, that is, in a "rinsing with water injection" manner. In this case, the injected water contains metal ions.

In the case of "rinsing with water injection", metal ions are added to the water injection, and thereby it is possible to cause a necessary amount of metal ions to adhere to the laundry without reducing the concentration of metal ions in water during "rinsing with water injection". When the sterilization effect is not emphasized, water containing no metal ions may be supplied so as to limit consumption of the electrodes 113 and 114.

Either one of the addition of the metal ion as the first treatment substance and the addition of the treatment agent (softener) as the second treatment substance is optional. Either or both of these addition operations may not be performed. When both the adding operations are not performed, the flow advances from step S420 to step S401, and such an operation has already been described. From now on, the addition of either of the two treatment substances will be described.

In step S421, when the treatment substances desired to be added are not two, that is, the metal ions and the softener, it means that only one of them is selected for addition. In this case, the flow advances to step S426.

In step S426, it is detected whether the treatment substance to be added is a metal ion. When it is confirmed that the metal ions are present, the flow proceeds to step S427; otherwise, the flow advances to step S428.

In step S427, the main water inlet valve 50a is opened and water flows into the main water inlet passage 52 a. The sub water inlet valve 50b is not opened. When water flows through the ion elution device 100, the drive circuit 120 applies a voltage between the electrodes 113 and 114, which elutes ions of the metal comprising the electrodes into the water. When it is confirmed that a predetermined amount of water containing metal ions has been injected into the washing tub 30 and a predetermined metal ion concentration can be obtained in the rinsing water by adding water not containing metal ions to a set water level, the application of voltage to the electrodes 113 and 114 is stopped. After the ion elution device 100 stops generating the metal ions, the main water inlet valve 50a continues to supply water until the water level inside the washing tub 30 reaches a set height.

After step S427, the flow advances to step S423. Thereafter, in the same manner as when the metal ions and the treatment agent (softener) are added simultaneously, the flow advances from step S423 (strong spinning) to step S424 (gentle spinning), and then to step S425 (strong spinning) and step S406 (uniform scattering of laundry). The gentle spinning time period may be replaced with a static time period.

If the treatment substance to be added is not a metal ion in step S426, the treatment substance will be a treatment agent (a softener). In this case, the flow advances to step S428.

In step S428, both the main water inlet valve 50a and the sub water inlet valve 50b are opened, and water is supplied into the main water inlet passage 52a and the sub water inlet passage 52 b. However, the ion elution device 100 is not activated, and no metal ions are generated. After water sufficient to cause a siphon action is supplied to the treating agent chamber 55 and the treating agent (softener) is injected into the washing tub 30 by means of the siphon tube 57, the sub water inlet valve 50b is closed.

After the sub water inlet valve 50b is closed, the main water inlet valve 50a continues to supply water, and stops supplying when the water level inside the washing tub 30 reaches a set height.

After step S428, the flow advances to step S423. Thereafter, in the same manner as when the metal ions and the treatment agent (softener) are added simultaneously, the flow advances from step S423 (strong spinning) to step S424 (gentle spinning), and then to step S425 (strong spinning) and step S406 (uniform scattering of laundry). The gentle spinning time period may be replaced with a static time period.

In this way, even if only one type of treatment substance is added, it is necessary to take various steps from strong spinning to gentle spinning, and then to strong spinning, in order to ensure that the treatment substance adheres to the laundry. However, since it is not necessary to equalize the time distribution for the metal ions and the time distributionfor the treatment agent (softener), the step time distribution is adjusted to suit the type of treatment substance.

Unlike metal ions, it does not take a long time for the treatment agent (softening agent) to adhere to the laundry. Therefore, only step S423 (strong spinning) and step S406 (uniform spreading of laundry) may be employed after step S428, and step S423 (strong spinning) may end in a short time, such as two minutes, for example.

When the laundry is not uniformly dispersed in step S406, the washing machine 1 may be shaken vigorously in the subsequent dehydration operation. The chattering due to the uneven distribution of the laundry is detected using a physical detection device such as a touch sensor, a vibration-type sensor, an acceleration sensor, and the like, or by software analysis of a voltage-current map of the motor 41.

When the uneven distribution of the laundry is detected, the spinning of the washing tub 30 is stopped, and the water is supplied again and agitated so as to resume the even distribution of the laundry. Such uniform distribution restoration is referred to as "rinsing operation for correcting the uneven distribution of the laundry".

Fig. 16 is a time chart showing performance of respective elements in a rinsing operation for correcting uneven distribution of laundry. After the water supply is finished, the water is vigorously stirred for a first stirring period to change the arrangement of the laundry. Thereafter, in the second stirring period, stirring is slowly performed at short time intervals to uniformly spread the laundry so as to be ready for the restart of the spinning. The time distribution ratio is, for example, two minutes and five seconds for the water supply operation, one minute for the first stirring operation, and 30 seconds for the second stirring operation.

During the stirring, the motor 41 is periodically and repeatedly turned on (forward rotation), turned off, turned on (reverse rotation), and turned off. The ratio of the on time to the off time varies according to the volume of water and/or the amount of laundry. For example, the time ratio (on/off) during operation at rated load is as follows: (the unit is second)

First stirring operation 1.9/0.7

Second stirring operation 0.9/0.4

In the final-rinsing operation, when the uneven scattering of the laundry is detected during the dehydrating operation after the metal ions are added, a different countermeasure is taken from when no metal ions are added and the uneven scattering of the laundry is detected.

The first "different countermeasure" is "supply of water containing metal ions to perform a rinsing operation for correcting uneven distribution of laundry". In this way, in the case of performing the rinsing operation for correcting the uneven distribution of the laundry using the supplied fresh water, since the metal ions are added to the water, the antibacterial treatment effect on the laundry is not weakened.

When the rinsing operation for correcting uneven distribution of laundry is performed using the supplied water containing metal ions, it is preferable that the amount of metal ions to be added is smaller than that in the previous operation. In this way, it is not necessary to replenish the laundry, which has been treated once with metal ions, with an unnecessarily large amount of metal ions, and thus the consumption of metal ions can be limited.

The second "different countermeasure" is "supply and stir water containing no metal ions to perform a rinsing operation for correcting uneven distribution of movement while indicating and/or informing that the injected water contains no metal ions".

When water containing metal ions is used while correcting the uneven distribution of the laundry, the metal in the electrodes 113 and 114 is consumed more quickly than the designed service life, and the time when the metal ions are not available comes earlier. However, in the foregoing manner, when the rinsing operation for correcting the uneven distribution of the laundry is performed by using water containing no metal ions, in order to limit the consumption of the metal ions, the actual situation is indicated and/or notified to the user by means of display or sound information on the operation/display panel 81, so that the user can know that the intended antibacterial effect may not be obtained.

The third "different countermeasure" is "to stop the spinning rotation while indicating and/or informing that the actual condition of the uneven scattering of the laundry is detected".

In this way, by not performing the rinsing operation for correcting the uneven distribution of the laundry, and informing the user that the uneven distribution of the laundry has occurred and requiring the user to manually correct such unbalance, it is possible to obtain the antibacterial effect intended by the user while limiting the consumption of the metal ions.

When it is detected that the uneven distribution of the laundry is not the only cause, different countermeasures are taken for various causes.

If the rinsing operation for correcting the uneven distribution of the laundry is performed using water containing metal ions each time the uneven distribution of the laundry is detected, the metal as the metal ion source, that is, the electrodes 113 and 114, is consumed in a short time. However, with this configuration, by taking a countermeasure to correct uneven distribution of laundry without using water containing metal ions, it is possible to limit consumption of the electrodes 113 and 114.

As an alternative to the working process of the washing machine 1, it is possible to provide a plurality of countermeasures after the detection of the uneven distribution of the laundry, and the type and/or the execution order of these countermeasures may be selected.

In this way, it is possible for the user to autonomously determine the countermeasure. That is, the user can preferentially maintain the antibacterial effect by using a sufficient amount of metal ions, or preferentially save metal ions.

To start the ion elution device 100, the constant current circuit 125 in the drive circuit 120 controls the voltage so that the current flowing between the electrodes 113 and 114 is kept constant. Thereby, the amount of eluted metal ions per unit time becomes constant. When the amount of eluted metal ions per unit time is constant, the concentration of metal ions in the washing tub 30 can be controlled by controlling the volume of water flowing through the ion elution device 100 and the metal ion elution time, thereby easily achieving a desired concentration of metal ions.

The current flowing between the electrodes 113 and 114 is direct current. If the current is an alternating current, the following phenomenon occurs. That is, when the metal ions are silver ions, for example, when the polarity of the electrode is reversed, the silver ions that have been eluted are returned to the electrode by a reverse reaction, i.e. . However, this does not occur for direct current.

On either one of the electrodes 113 and 114, if it is used as a cathode, scale is deposited thereon. When direct current continues to flow without changing polarity and as a result the amount of deposited scale becomes large, the current is limited and the ion elution operation cannot be performed at a predetermined rate. Furthermore, the phenomenon of "single-sided depletion" occurs, i.e. only the electrode used as anode is consumed at a faster rate. Accordingly, the polarities of the electrodes 113 and 114 are periodically reversed.

Because of being used for metal ion elution, the electrodes 113 and 114 are gradually depleted, resulting in a decrease in the metal ion elution rate. When they are used for a long time, the metal ion elution rate becomes unstable, and a predetermined metal ion elution rate cannot be obtained. Thus, the ion elution apparatus 100 is enabled to be replaced, and when the useful life of the electrodes 113 and 114 expires, a new apparatus may be utilized instead. Further, the user is informed through the operation/display panel 81 that the service lives of the electrodes 113 and 114 are almost expired, and therefore, it is necessary to take appropriate countermeasures such as replacement of the ion elution device 100.

It will be understood that the present invention may be carried out in any other manner than that specifically set forth above as an example, and that numerous modifications and variations are possible within the scope of the invention.

It is also to be understood that the present invention may be applied to any other type of washing machine than the one concerned in the foregoing embodiments; that is, the present invention may be applied to all types of washing machines, such as a washing machine having a horizontal tub (e.g., a drum type), a washing machine having an inclined tub, a washing machine also used as a dryer, and a washing machine having two separate tubs.

Industrial applicability

The present invention finds wide use in washing machines, where the antibacterial action of metal ions on fabrics is attempted to be utilized irrespective of whether the washing machine is used in the home or in the industry.

Claims (14)

1. A washing machine in which antibacterial metal ions can be added to water in a predetermined operation during washing of laundry,

wherein the predetermined operation time is longer when the metal ions are added than when the metal ions are not added.

2. A washing machine in which antibacterial metal ions can be added to water in a predetermined operation during washing of laundry,

wherein the predetermined operation comprises a strong spinning time period and a gentle spinning time period, or a strong spinning time period and a static time period.

3. The washing machine as claimed in claim 2,

wherein a ratio of the strong spinning time period to the gentle spinning time period or a ratio of the strong spinning time period to the stationary time period is kept constant regardless of a volume of water and/or an amount of laundry in the washing tub.

4. The washing machine as claimed in claim 2,

wherein a ratio of the strong spinning time period to the gentle spinning time period or a ratio of the strong spinning time period to the stationary time period is varied according to a volume of water and/or an amount of laundry in the washing tub.

5. A washing machine in which 'rinsing with water injection' is enabled,

wherein the antimicrobial metal ions may be added to the supplied water during the "rinsing with water injection".

6. A washing machine in which antibacterial metal ions can be added to water in a predetermined operation during washing of laundry,

wherein, when the laundry is detected to be unevenly distributed during the dehydrating rotation of the washing tub after the metal ions are added, a different countermeasure may be taken from when the laundry is detected to be unevenly distributed while the metal ions are not added.

7. The washing machine as claimed in claim 6,

wherein the different countermeasure is rinsing for correcting uneven distribution of the laundry by agitating the laundry in water containing metal ions.

8. The washing machine as claimed in claim 7,

wherein, when the rinsing operation for correcting the uneven distribution of the laundry is performed using the replenished fresh water, the amount of the metal ions to be added is smaller than the amount added in the previous operation.

9. The washing machine as claimed in claim 6,

wherein the different countermeasure is to perform rinsing for correcting uneven scattering of the laundry by agitating the laundry in water containing no metal ions while indicating and/or informing that the supplied water contains no metal ions.

10. The washing machine as claimed in claim 6,

wherein the different countermeasure is to terminate the spinning rotation while indicating and/or informing that the uneven scattering of the laundry is detected.

11. The washing machine as claimed in claim 6,

wherein, when it is detected that the unbalance of the laundry is not the only cause, different countermeasures are taken for various causes.

12. The washing machine as claimed in claim 6,

wherein a plurality of countermeasures against the imbalance are provided, and the type and/or order of countermeasures to be taken can be selected.

13. The washing machine as claimed in claim 11,

wherein a plurality of countermeasures against the imbalance are provided, and the type and/or order of countermeasures to be taken can be selected.

14. Washing machine according to one of claims 1 to 13,

wherein the metal ions are generated by using an ion elution device that elutes the metal ions by applying a voltage between electrodes.

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