JP2001346747A - Dishwasher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems that the self cleaning and the charging of the detergent are forgotten since the self cleaning of a cleaning tank is manually made by the arbitrary judgment of a user. SOLUTION: The staining degree of an internal wall of the cleaning tank is automatically detected by a stain detecting means, and the self cleaning is automatically achieved using alkaline ion water by the output of the stain detecting means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dishwasher for washing, rinsing, and drying tableware stored in a washing tank, and more particularly to a self-cleaning function for washing the inside of the washing tank. And a dishwasher having the same.

[0002]

2. Description of the Related Art FIG. 11 is a schematic sectional view showing the structure of a conventional general dishwasher.

Referring to FIG. 1, a dishwasher 400 includes a front door 29 which can be opened and closed to take in and out the dishes to be washed, a rack 15 for installing the dishes 16 to be washed, and a rack 15. A washing tank 12 having a water storage section 48 for storing washing water in a downward direction;
2 and a rotatable cleaning nozzle 14 protruding substantially at the center.
And a plurality of injection holes 49 provided on the cleaning nozzle 14.
A thermistor 35 provided in the cleaning tank 12 for detecting the temperature of the cleaning water, a heater 40 for heating the cleaning water, and a float switch type for detecting the level of the cleaning water in the water storage section 48. A water level sensor 32, a cleaning pump 13 for supplying cleaning water to the cleaning nozzle 14, a drain pump 17 for discharging cleaning water to a drain pipe 18, a water supply pipe 19 for supplying cleaning water, A valve 47 for controlling water supply from the water supply pipe 19, a detachable filter 42 provided in the washing tank 12, and a drying fan 43 for blowing air for drying the washed dishes.
And a control device centered on a microcomputer including a warm air heater 44 for heating the air blown from the drying fan 43 and a CPU (abbreviated central processing unit) for controlling the entire dishwasher. 411.

A predetermined amount of detergent for washing is manually poured into a detergent introduction box (not shown) every time before opening the front door 29 and washing. This detergent is a dishwasher-specific detergent and is difficult to obtain due to limited retailers.

[0007] The dirt removed by the detergent is filtered by a filter 4.
2 to capture. The accumulated residue is taken out of the filter 42 and discarded.

[0006] The dirty and washed water passing through the filter 42 is drained to the sewage through the drain pipe 18 by operating the drain pump 17.

In operation, the water reservoir 48 in the cleaning tank 12 is operated.
Is supplied with tap water through a water supply pipe 19 when a valve (water supply electromagnetic valve) 47 is opened. The amount of water stored in the water storage unit 48 is detected by the water level sensor 32, and when the water amount reaches the specified amount, the control device 411 stops the operation of the valve 47. Since the heater 40 and the thermistor 35 are provided, the water temperature in the water storage section 48 can be heated to a predetermined temperature.
The heater 40 produces warm water for cleaning and rinsing.

When the washing and rinsing steps are completed, the heater 4
By operating the fan 4 and the fan 43, hot air is blown into the washing tank 12, and the tableware 16 is dried.

FIG. 12 is a view showing an operation section of the dishwasher of FIG. Although not shown in FIG. 11, the operation unit 60 is provided at a position on the front of the dishwasher 400 where the user can easily operate. The operation unit 60 controls the dishwasher 400 in a mode display lamp group 241 that indicates the current operation mode by blinking, a mode switch 242 pressed to switch the operation mode, and an operation mode designated by the mode switch 242. A start switch 243 pressed to start operation, a stop switch 244 pressed to stop operation of the dishwasher 400, and a message for operation or displaying a warning or the like to a user. It comprises a display unit 25.

When an operation mode is designated by the mode switch 242, a lamp corresponding to the designated operation mode of the mode display lamp group 241 is turned on.

Normally, the start switch 24 of the operation unit 60
When 3 is turned on (pressed), a series of steps of washing → rinsing → drying is continuously operated. When the mode switch 242 is sequentially pressed, an arbitrary mode indicated by the mode display lamp group 241 can be selected, and operation of only the selected mode becomes possible.

A series of these operations are controlled by the control device 411. The control device 411 includes a microcomputer, and performs processes such as storage, judgment, comparison, calculation, signal acquisition, and relay control.

In a series of operations, the filter 42
Even if the residue is removed and dirty water is drained, an odor remains inside the cleaning tank 12 and oil, starch,
Proteins and the like adhere. These deposits are added as dirt and odor components at the next cleaning, and deteriorate the cleaning performance. In particular, as the number of uses increases, the degree of dirt also deteriorates.

For this reason, conventionally, the cleaning tank 12 is periodically arranged.
There is a type in which a detergent is put in the washing machine 400 without accommodating the tableware 16 and the washing machine 400 is operated idle, or a special self-cleaning mode is provided as disclosed in Japanese Patent Application Laid-Open No. 5-146390.

According to the technique disclosed in this publication, the timing for performing the self-cleaning operation is determined by the user independently determining the dirt and smell of the cleaning tank 12. Then, based on the determination result, if necessary, the switch for self-cleaning provided on the operation unit is operated. At this time, the cleaning tank 12
The rack 15 in the inside is set in a state where the detergent is put in a predetermined detergent box without the tableware 16.

In this case, when the self-cleaning switch is pressed, the apparatus operates in a self-cleaning mode such as washing and rinsing. The washing water temperature at this time is equivalent to the maximum washing water temperature of 60 ° C. to 70 ° C. in the normal dishwashing mode.

The maximum water temperature in the normal dishwashing mode is determined because lacquerware such as lacquer coating cannot withstand further warm water.

As described above, by performing the self-cleaning operation, the dirt and smell in the cleaning tank 12 are reduced and kept clean, so that the dishwashing ability for the next and subsequent times is kept good.

As a dishwashing method, Japanese Patent Application No. Hei 6-187407 and JP-A-6-187407 disclose a technique in which alkaline ionized water and acidic ionized water are previously generated by an electrolytic bath and used in a dishwasher.
No. 319,673 and Japanese Utility Model Laid-Open No. 5-26051.

[0020]

In the conventional dishwasher as described above, it is necessary to add a detergent even in a self-cleaning operation. Therefore, if the user forgets to input the detergent, there is a disadvantage that the self-cleaning effect is reduced and the dirt and smell in the cleaning tank are hardly reduced.

In a normal dishwasher, since the dishes in the washing tank cannot be seen from the outside, the self-cleaning operation may be performed by mistake while the dishes are stored in the washing tank. The self-cleaning operation causes the tableware, which has been washed and dried and left in the tank, to be re-adhered to water.

Further, since the start of the self-cleaning operation is left to the user, if the user forgets to operate the switch for starting the self-cleaning, the dirt in the cleaning tank becomes severe, the odor remains, and the dishwashing performance deteriorates. There is a problem of coming. On the other hand, wasteful energy is wasted even if the self-cleaning is operated frequently. As described above, conventionally, an appropriate self-cleaning time is unclear, and the operation has been troublesome manually.

Further, since the temperature of the washing water during the self-cleaning operation is equal to the maximum water temperature at the time of washing the dishes, the washing water temperature is more than the degree to which dirt such as stubborn oil components adhering to the inner wall of the washing tank is washed in the dish washing mode. Had a problem that it was not washed.

As described above, since the conventional self-cleaning operation largely depends on the judgment and operation of the user, the operation is troublesome for the user. In addition, the washing ability was about the same as dishwashing, and the inside of the washing tank could not be sufficiently washed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a dishwasher capable of improving operability and cleaning ability relating to self-cleaning for cleaning a cleaning tank.

[0026]

DISCLOSURE OF THE INVENTION The dishwasher of the present invention comprises:
Receiving means for receiving at least supplied water, comprising a cleaning mode for cleaning at least tableware contained in the cleaning tank and a self-cleaning mode for cleaning the inside of the cleaning tank. Generating means for generating alkaline ionized water from the received water, dirt detecting means for detecting dirt on the inner wall of the cleaning tank, and specifying a self-cleaning mode according to the detection output of the dirt detecting means, Cleaning means for automatically cleaning the inside of the cleaning tank using the generated alkaline ionized water. .

[0027]

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

FIG. 1 is a block diagram of a dishwasher with a self-cleaning function according to an embodiment of the present invention.

Referring to FIG. 1, the structure of the main part of dishwasher 100 with a self-cleaning function is similar to that of conventional dishwasher 400 shown in FIG.
And the tableware detection device 22 are added, and the other configuration is basically the same, so that the description thereof is omitted.

Here, unlike the conventional dishwasher 400, a water supply process relating to self-cleaning, which is also a feature of the present invention, and a stain detecting device 21 in the washing tank 12 are described.
A dirt detection function using the like and a tableware detection function by the tableware detection device 22 will be described.

With respect to the water supply process, tap water 50 supplied from a water pipe faucet is supplied to the electrolytic cell 2 via a valve 1 provided between the water supply pipes 19 and 20. The cathode water pipe 3 taken out of the electrolytic cell 2 is connected to an alkali ion water tank 5, and the anode water pipe 4 also taken out of the electrolytic cell 2 is connected to an acidic ion water tank 6.

In the alkaline ionized water tank 5, alkaline ionized water 7 supplied through the cathode water pipe 3 is stored to a predetermined water level, and the acidic ionized water tank 6 is also supplied with the acidic ionized water 8 supplied through the anode water pipe 4. Up to the water level. Valves 9 and 10 are provided below the alkaline ionized water tank 5 and the acidic ionized water tank 6, respectively, and are connected to a cleaning water supply pipe 11 connected to the inside of the main body of the cleaning machine.

For the production of alkaline ionized water and acidic ionized water in the electrolytic cell 2, for example, the method proposed in Japanese Patent Application No. 6-187407 by the present inventors is applied.

Briefly, a plurality of anode plates are provided in the electrolytic cell 2 leading to a water supply pipe 20 connected to a water pipe tap.
A plurality of cathode plates are arranged to face each other via a partition provided with a plurality of openings. Tap water 50 includes a cathode plate chamber that houses each of the cathode plates partitioned by each of the partition walls,
It is led to the anode plate chamber containing the anode plate, which is partitioned by each of the partition walls.

Here, when a DC voltage is applied between the anode plate and the cathode plate of the electrolytic cell 2, the supplied tap water 50 is electrolyzed, passes through the opening of the partition wall, and enters the cathode water (alkali ion water) into the cathode plate chamber. 7 and anode water (acidic ion water) 8 are generated in the anode plate chamber.

FIG. 2 is a sectional view of a main part of the dirt detecting device 21 of FIG. FIG. 3 is a diagram showing a peripheral circuit of a microcomputer (hereinafter abbreviated as a microcomputer) 28 built in the control device 41 of FIG.

FIG. 4 is an internal block diagram of the microcomputer 28 of FIG. FIG. 5 shows the microcomputer 2 of the control device 41 of FIG.
FIG. 8 is a diagram showing various relay switches controlled based on the reference numeral 8 and peripheral circuits thereof.

As shown in FIG. 3, the microcomputer 28 is connected to an operation unit 24 provided at a position where the user can easily operate, such as the front surface of the main body of the dishwasher. The operation of the main body is controlled, and a message is appropriately edited and given to the operation unit 24.

The operation unit 24 is a mode display lamp group 241 for displaying the designated operation mode of dishwashing or the current operation mode (washing, rinsing, drying) by blinking or lighting a lamp, and for switching the designated operation mode by pressing down. Mode switch 242, a self-cleaning mode switch 26 for designating a self-cleaning operation mode when pressed, and a mode switch 242 when pressed.
Switch 33 and stop switch 2 for starting and stopping the operation mode designated by or 26
44, and a microcomputer 2 for operation / operation to the user
And a display unit 25 for displaying a message (including a warning) from the display unit 8.

Further, the microcomputer 28 includes the dirt detecting device 21.
And the tableware detection device 22 are connected.

The dirt detector 21 is disposed on the inner wall of the cleaning tank 12, and is disposed near the surface of the cleaning water stored in the water storage section 48 (see FIG. 1).

Referring to FIGS. 2 and 3, dirt detecting device 2
1 includes two metal electrodes 36 and a resin base 37, and the two electrodes 36 are fixed to the resin base 37 so as to face each other with a certain space distance (5 to 20 mm).
As shown in FIG. 3, one of the two electrodes 36 is connected to the ground side, the other is connected in series to one end of a resistor R1 (about several kilohms), and the other end of the resistor R1 is connected to a DC voltage V.
d is applied. The divided voltage V between the resistor R1 and the electrode 36
Y is transmitted to the microcomputer 28 as an input signal. At the time of drying, the resistance value between the electrodes 36 is high (in units of megohms), so that the voltage VY across the dirt detection device 21 is high.

When the use time and the number of times of cleaning increase,
Dirt adheres to the inside of the cleaning tank 12 and odor remains. Foreign substances such as food residues such as oils and fats and starch and dirt also adhere between the electrodes 36 of the dirt detection device 21. When the amount of dirt is small, the resistance between the electrodes 36 is large. However, when the amount of dirt is large, the resistance value decreases according to the amount of dirt.

When the dishwashing → rinsing process is completed, the wastewater collected in the water storage section 48 by the drainage pump 17 is drained to sewage or the like, and the water in the washing tank 12 is exhausted.

Then, the heater 44 and the fan 43
N, the inside of the cleaning tank 12 gradually becomes dry.

At this point, the voltage VY of the stain detector 21 is
Is read by the microcomputer 28. When there is little dirt, when dried, the value of the resistance at both ends of the electrode 36 increases and the voltage V
Y also gets higher. If the dirt gets worse, the electrode 3
The resistance at both ends of No. 6 does not increase and does not return with a small resistance value. Thus, dirt can be detected according to the value of the voltage VY.

The voltage VY is preferably read at a timing close to the end of drying. This is to prevent water droplets and the like at the time of cleaning from adhering to the electrode 36 to prevent malfunction.

As described above, the dishwasher 100 includes the washing tank 1
The contamination in the cleaning tank 12 can be physically detected based on the potential difference between the pair of electrodes 36 provided on the inner wall of the cleaning tank 12.

The above-described detection of dirt is a method using the dirt detecting device 21. However, since the dirt and odor in the cleaning tank 12 increase in proportion to the number of uses or the use time for washing dishes, they are used to some extent. And self-cleaning is appropriate.

Therefore, each time the dishwashing operation is performed, the time and the number of times the main body actually operates are accumulated and stored each time. This storage operation is performed when the dishwashing operation is completed.

The accumulated value is compared with a predetermined threshold value for starting self-cleaning, and if it is determined that the value is larger than the threshold value, a self-cleaning reminder is issued.

Referring to FIG. 3, dish detector 22 includes a light emitting diode 30 and a phototransistor 31. These optical sensor elements are arranged near the upper part of the rack 15 (see FIG. 1). A light emitting diode 30 and a phototransistor 31 are provided at positions of holes formed on both side walls of the cleaning tank 12 so as to face each other.

If there is no tableware 16 in the washing tank 12, the light emitted from the light emitting diode 30 reaches the opposing phototransistor 31, turns on the phototransistor 31, and the voltage value across the resistor R1 becomes Vd.

If the tableware 16 is present, the light from the light emitting diode 30 is blocked by the tableware 16 and does not reach the phototransistor 31, so that the phototransistor 31 is turned off and the voltage value across the resistor R1 becomes zero. This voltage value is provided to the microcomputer 28 as a dish detection signal.

Referring to FIG. 5, AC power supply AC supplied to the dishwasher is supplied to each section.

The electrolytic cell 2 having two electrodes 39 for electrolysis is provided with a DC power generator 23 for supplying DC power for electrolysis of water. The DC power generator 23 is ON / OFF controlled by a relay switch RS1 connected in series.

Each of the valves 47, 1, 9 and 10 has a relay switch RS2, RS3, R connected in series.
ON / OFF control is performed by each of S4 and RS5.

The cleaning pump 13 is controlled by a relay switch RS6, the heater 40 is controlled by relay switches RS6 and RS5a, the drain pump 17 is controlled by a relay switch RS7 connected in series, and the fan 43 and the drying heater 44 are connected by a relay connected in series. ON / OFF control is performed by the switch RS8.

Each of the relay switches RS1 to RS8 is centrally controlled by the microcomputer 28.

Referring to FIG. 4, microcomputer 28 has a CPU 28
The CPU 280 connects an interface unit 281, a timer 282, a RAM (random access memory) 283, and a ROM (read only memory) 284 for connecting the CPU 280 to various circuits connected to the outside of the microcomputer 28.

The timer 282 can individually measure the time required for washing with alkaline ionized water and acidic ionized water for dishwashing, rinsing and drying, and self-cleaning, and also measures a series of time required for dishwashing, rinsing and drying. it can.

The RAM 283 includes a variable area 285 and a program area 286 for storing various programs, and the ROM 284 includes a variable area 287 and a program area 288 for storing various programs.

In the variable area 285, the cumulative use number N1 of the value obtained by counting up (accumulating) each time the dishwasher 100 is used for the dishwashing operation and the time used for each dishwashing operation are shown. The accumulated use time N2 of the value obtained by accumulation is stored.

In the variable area 287, the specified voltage value VS1 when there is no tableware, which is the output voltage value of the tableware detecting device 22 for determining that there is no tableware, and whether the water in the water storage section 48 has reached a predetermined water level is determined. Voltage value VS2 of the feedwater level, which is the output voltage value of the dirt detection device 21 for
The specified voltage value VS3 for dirt detection, which is the output voltage value of the dirt detection device 21 for determining that the dirt in the inside has reached the level required for self-cleaning, is stored. Each of the voltage values VS1 to VS3 is equal to or greater than 0 and the power supply voltage Vd.
Takes the following values:

The area 287 includes specified water temperatures TE1 and TE2 for dishwashing and self-cleaning of the stored water in the water storage section 48, a specified cleaning time TM1 set for dishwashing, and water stored in the water storage section 48. Drainage time TM2 set for draining all dishes, specified rinse time TM3 set for tableware rinsing, specified drying time TM4 set for drying tableware, alkaline ionized water for self-cleaning and The specified cleaning times TM5 and TM6 set for cleaning the inside of the cleaning tank 12 with acidic ion water are stored.

Further, in the area 287, a specified number of use times TN1 and a specified use time TN2, which are the number of dishwashing operations and the operation time of the main body, which are set as a guide for starting self-cleaning, are stored.

The various variable values stored in the above-described variable area 287 are determined by experiments, usage surveys, and the like.

FIG. 6 is a flowchart of a process of checking the presence or absence of tableware using the tableware detection device 22 according to one embodiment of the present invention.

FIG. 7 is a flowchart of a process of supplying water to the water storage section 48 using the water level detecting function of the dirt detecting device 21 according to one embodiment of the present invention.

FIG. 8 is a flow chart of the washing and rinsing steps of the dish according to one embodiment of the present invention.

FIG. 9 is a flowchart of a tableware drying process according to an embodiment of the present invention.

FIG. 10 is a flowchart of a self-cleaning process according to one embodiment of the present invention.

The flowcharts of FIGS. 6 to 10 show the program area 28 of the ROM 284 as a program in advance.
8 is executed under the control of the CPU 280.

Each of the flowcharts in FIGS. 6 to 10 includes processing steps Si (i = 1, 2, 3,...), And is abbreviated as Si in the following description.

Referring to FIG. 6, tableware 16 in washing tank 12 is provided.
When checking the presence / absence of, the CPU 280 first turns on the light emitting diode 30 via the interface unit 281, so that light is emitted from the light emitting diode 30 to the phototransistor 31 provided opposite thereto (S1).

Next, the CPU 280 is connected to the interface unit 2.
81, the output voltage value obtained by the photoelectric conversion of the phototransistor 31 is read into a temporary variable e, and the value of the variable e and the ROM
284 is compared with the specified voltage value VS1 when there is no tableware (S
2, S3).

If the tableware 16 is provided, the light from the light emitting diode 30 is blocked and is not received by the phototransistor 31, so that the value of the variable e is 0. Is the power supply voltage Vd.

As a result of the comparison, if e <VS1, it is determined that the tableware 16 is in the washing tank 12 (S4), and if not e <VS1, it is determined that the tableware 16 is not in the washing tank 12 (S4).
5).

Referring to FIG. 7, when water is supplied to water storage section 48 during dishwashing or self-cleaning, first, CPU 2
80 turns on the relay switch RS2 via the interface unit 281, so that the valve 47 is opened.
Water is supplied to the water storage section 48 (S6, S7).

During the water supply, the CPU 280 reads the output voltage VY of the dirt detection device 21 via the interface unit 281 and compares the value of the output voltage VY with the specified voltage value VS2 of the water supply level in the ROM 284 (S8, S9).

While the comparison result is not VY <VS2, it is determined that the water level has not yet reached the specified water level for dishwashing or self-cleaning, and water supply is continued. That is, S
The loop from 7 to S9 is repeated.

On the other hand, when VY <VS2, it is determined that the water level in the water storage section 48 has reached the specified water level, and the CPU 280 turns off the relay switch RS2 via the interface section 281 to close the valve 47 (S10). Thus, the water supply to the water storage section 48 ends.

Referring to FIGS. 8 and 9, dishwasher 100
The following describes the operation of washing dishes, rinsing dishes, and drying dishes, which is similar to the related art.

First, the CPU 280 is connected to the interface unit 2
In response to an instruction to start cleaning from the operation unit 24 via 81, measurement of the cleaning time is started using the timer 282, and water is supplied to the water storage unit 48 to the specified water level for cleaning according to the flowchart of FIG. S11).

Thereafter, the CPU 280 sets the relay switch R
S6 and RS5a are turned on, and the cleaning pump 13 and the heater 40 are turned on.
Are driven (S12). Thus, the stored water in the water storage section 48 is heated, and the washing is started. And C
The PU 280 compares the measurement time of the timer 28 with the specified cleaning time TM1 of the ROM 284 to determine whether the specified cleaning time has elapsed (S13).

If the specified cleaning time TM1 has not elapsed,
The CPU 280 reads the detected voltage value of the thermistor 35, converts it into a corresponding temperature, and determines whether or not the specified water temperature TE1 at the time of cleaning the ROM 28 has been reached (S14, S15).

If the result of determination is that the specified water temperature TE1 has not been reached, the process returns to S12 and thereafter to continue heating, but if the specified water temperature TE1 has been reached, the heater 40 is turned off by the relay switch RS5a (S16), and S13 Move to the subsequent processing.

On the other hand, if the specified cleaning time TM1 has elapsed in S13, the CPU 280 turns off the pump 13 via the relay switch RS6 and ends the cleaning (S1).
7).

Then, the CPU 280 sets the relay switch R
S7 is turned on to drive the drain pump 17 to drain the sewage in the water storage section 48 after the cleaning is completed (S18). The drainage time is measured by the timer 282, and the CPU 280 determines that the measured drainage time is the specified drainage time TM2 of the ROM 284.
Continue draining until the progress of is indicated. On the other hand, when the specified drainage time TM2 has elapsed, the relay switch RS7 is turned off.
To stop the drainage pump 17 and finish draining (S1).
9, S20).

Next, in order to rinse the washed tableware 16, the CPU 280 again supplies water to the water storage section 48 for rinsing according to the flowchart of FIG. 7 (S21).

Then, the CPU 280 sets the relay switch R
S6 and RS5a are turned on to drive the heater 40 and the pump 13 to start rinsing and to heat the water in the water storage section 48 (S22).

At the start of rinsing, the timer 282 starts measuring the rinsing time. This rinsing operation continues until the time measured by the timer 282 indicates that the specified rinsing time TM3 in the ROM 284 has elapsed (S22, S23).
However, if the specified rinsing time TM3 has elapsed, the CPU 280
Turns off the relay switches RS5a and RS6, stops the heater 40 and the pump 13, and ends the rinsing (S24).

When the rinsing is completed, the CPU 280 turns on the relay switch RS7 to drive the drain pump 17 to drain the waste water resulting from the rinsing of the water storage section 48 (S25).

At the start of drainage, the timer 282 starts measuring the drainage time. This draining operation is performed by the timer 28
2 measured drain time TM2 in ROM 284
(S25, S26), but when the specified drainage time TM2 has elapsed, the CPU 280 turns off the relay switch RS7 and stops the drainage pump 17,
The drainage ends (S27).

Then, the process proceeds to a step for drying the tableware 16 that has been washed and rinsed (S28).

Referring to FIG. 9, when drying tableware 16 after rinsing, first, CPU 280 sets relay switch RS8 to OFF.
N to drive the heater 44 and the fan 43,
Dish-drying is started by sending hot air into 2.

At the start of the dish drying, the timer 282
Starts measuring the dish drying time. As long as the time measured by the timer 282 does not indicate the elapse of the specified drying time TM4 in the ROM 284, the dish drying operation continues (N in S30).
O).

During the tableware drying operation period, the CPU 280
Is the cumulative time N2 and cumulative number N1 of the actual operation of the dishwasher 100 so far and the ROM
284 prescribed use time TN2 and prescribed use number TN1
And the accumulated time N2 is equal to the prescribed use time T.
It is determined whether N2 has been reached or the cumulative use count N1 has reached the prescribed use count TN1 (S31).

As a result of the determination, if at least one of the use time and the number of uses has reached the specified value, the CPU 2
80 sets 1 to a temporary variable F (S32).

The drying time TM4 specified by the timer 282
Is measured (YES in S30), the CPU 28
0 reads the output voltage VY of the dirt detector 21 (S3
3).

Then, the CPU 280 determines whether or not F = 1 or the value of the voltage VY <the specified voltage value VS3 for dirt detection (S34).

If the CPU 280 determines that F = 1 or VY <VS3 (YES in S34), it determines that the degree of dirt in the cleaning tank 12 is considerably advanced (S35), and prompts the display unit 25 to perform self-cleaning. Is displayed or notified by a buzzer (not shown) (S36).

Then, the CPU 280 determines that the cumulative use number N1
Is incremented by +1 and updated, and the current cleaning measured by the timer 282 during the cumulative use time N2 →
A series of operation times from rinsing to drying are accumulated and updated (S
37).

The cumulative use number N1 and the cumulative use time N2 are reset each time self-cleaning ends.

The notification of the self-cleaning reminder described above may be made every time the dishwasher 100 is operated from the time when it is determined that the inside of the washing tank 12 is dirty (S35) to the time when the self-cleaning is performed. Good.

Next, the self-cleaning operation will be described with reference to the flowchart of FIG.

In response to the self-cleaning reminder,
The user operates the self-cleaning switch 26 of the operation unit 24.
When is pressed, the CPU 280 reads this input signal and shifts the dishwasher 100 to the self-cleaning operation mode (S38).

The CPU 280 according to the operation mode designation
6 determines that the tableware 16 is not in the washing tank 12 according to the flowchart of FIG. 6 (S39). If there is the tableware 16, the display unit 25 or a buzzer (not shown) displays or warns an error indicating the presence of the tableware (S40, S41). ). This is because if the tableware 16 is in the washing tank 12, the self-cleaning function is impaired, and the user is instructed to take out the tableware.

On the other hand, if there is no tableware, the CPU 280 turns on the relay switch RS3 and turns on the valve 1 (the electromagnetic switching valve at the 3 port 2 position), so that the route of the tap water 50 that has passed through the water supply pipe 19 from the tap is the electrolytic cell. The mode is switched to the second side (S43). Normally, valve 1 is OFF, so water supply pipe 19
Tap water 50 is supplied from the valve 47 to the cleaning tank 12 side.

Next, the CPU 280 turns on the switch RS1.
Then, the water supplied to the electrolytic cell 2 is electrolyzed, and the obtained alkaline ionized water and acidic ionized water are stored in the tanks 5 and 6, respectively (S44).

Next, the CPU 280 sets the relay switch RS
4 and RS5, turn on valve 9 and turn on valve 10
F, alkaline ionic water is supplied into the cleaning tank 12 according to the flowchart of FIG. 7 (S45, S4).
6). Thereby, when the alkaline ionized water accumulates in the water storage section 48, the CPU 280 responds to the output of the dirt detection device 21.
Cleans the inside of the cleaning tank 12 for the specified cleaning time TM5 according to the flow chart of the cleaning step in FIG. 8 (S47, S4).
8).

At this time, the set temperature relating to the water temperature (the specified water temperature TE2 at the time of self-cleaning) is set 5 to 10 ° C. higher than the maximum set temperature at the time of washing dishes. At the time of this cleaning, the cleaning pump 13 is turned on, and while the nozzle 14 is rotating, the alkaline ionized water is discharged from the injection hole 49 through the cleaning tank 10.
Deposits that are sprayed inside and become dirt and odor components adhered to the cleaning tank 12 are cleaned.

When cleaning for a predetermined time (predetermined cleaning time TM5 with alkaline ionized water TM5) with the alkaline ionized water is completed (YES in S48), the pump 17 is turned on to remove the dirt on the inner wall of the cleaning tank 12. Is discharged to the sewer through the drain pipe 18. When discharge is completed, pump 17 is turned off.
F and stop the drainage (S49, S50).

Next, according to the flowchart of FIG. 7, the valve 10 is turned on to supply the acidic ionized water 8 stored in the tank 6 into the washing tank 12 (S51). Thereafter, the cleaning pump 13 and the heater 40 are turned on in the same manner as the alkaline ionized water according to the flow chart of the cleaning step in FIG. (S52, S5)
3).

When the washing is completed, the drain pump 17 is turned on.
Then, drainage is performed (S54). When drainage ends, a series of self-cleaning operations ends.

The washing with the alkaline ionized water and the acidic ionized water may be repeated. The self-cleaning effect increases as the number of repetitions increases.

Alkaline ionized water used for self-cleaning has a cleaning effect on oil stains such as fat, and acidic ionized water has a sterilizing and disinfecting effect.
The inside is kept clean and the generation of odor can be suppressed.

Since the dishwasher 100 cleans the interior of the cleaning tank 12 after cleaning with alkaline ionized water using acidic ionized water, the cleaning effect is further improved as compared with the cleaning using only alkali ionized water.

Although the above-described self-cleaning uses alkaline ionized water and acidic ionized water, it is also possible to generate only alkaline ionized water and perform cleaning using only this.

Since the dishwasher 100 further has a mode switch 26 for designating a self-cleaning mode when operated externally, the user can start the self-cleaning of the washing tank 12 at a desired time. Can be.

The above-described self-cleaning is started in response to the depression of the self-cleaning mode switch 26 of the operation unit 24. Regardless of whether or not the self-cleaning mode switch 26 is pressed, the cleaning tank 12 is detected as dirty. When it is time to issue a warning for self-cleaning prompting based on the detection output of the device 21 or the accumulated use count or accumulated use time, the mode is automatically shifted to the self-cleaning mode and the operation is started. For this reason, first, when the CPU 280 determines that there is no tableware in the washing tank 12 based on the output signal of the tableware detecting device 22, it generates alkali ionized water and acidic ionized water as described above, and the inside of the washing tank 12 is automatically generated. Wash. Thereby, cleaning can be performed without bothering the user.

The normal dishwashing by the dishwasher 100 may be a method using alkali ionized water or acidic ionized water as proposed in Japanese Patent Application No. 6-187407.

[0123]

According to the present invention, self-cleaning of the inside of the cleaning tank can be automatically performed by detecting that the degree of contamination of the inner wall of the cleaning tank has reached a certain level or more by the dirt detecting means. In addition, no detergent is required because of washing with alkaline ionized water, and performance degradation due to forgetting to add detergent or forgetting to perform self-cleaning can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of a dishwasher with a self-cleaning function according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the dirt detection device of FIG.

FIG. 3 is a diagram showing a peripheral circuit of a microcomputer built in the control device of FIG. 1;

FIG. 4 is an internal block diagram of the microcomputer of FIG. 3;

FIG. 5 is a diagram showing various relay switches controlled based on a microcomputer of the control device shown in FIG. 1 and peripheral circuits thereof.

FIG. 6 is a flowchart of a process of checking presence / absence of tableware using the tableware detection device according to one embodiment of the present invention.

FIG. 7 is a flowchart of a process of supplying water to a water storage unit using a water level detection function of the dirt detection device according to one embodiment of the present invention.

FIG. 8 is a flowchart of a dishwashing step → rinse step according to an embodiment of the present invention.

FIG. 9 is a flowchart of a tableware drying process according to an embodiment of the present invention.

FIG. 10 is a flowchart of a self-cleaning process according to one embodiment of the present invention.

FIG. 11 is a schematic sectional view showing a configuration of a conventional general dishwasher.

FIG. 12 is a view showing an operation unit of the dishwasher in FIG. 11;

[Explanation of symbols]

 2 Electrolysis tank 3 Cathode water pipe 4 Anode water pipe 5 Alkaline ion water tank 6 Acid ion water tank 7 Alkaline ion water 8 Acid ion water 12 Wash tank 16 Tableware 21 Dirt detection device 22 Tableware detection device 24 Operation unit 25 Display unit 26 Self cleaning mode Switch 28 Microcomputer 41 Control device 100 Dishwasher The same reference numerals in each figure indicate the same or corresponding parts.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yasuhiro Yasuda 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Masaji Fukui 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka No. Sharp Corporation (72) Inventor Eijiro Nakagawa 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Sharp Corporation (72) Eijiro Iguchi 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Sharp Co., Ltd. F term (reference) 3B082 DA02 DB03 DC01

Claims (1)

[Claims] 1. A dishwasher having at least a washing mode for washing dishes contained in a washing tank and a self-cleaning mode for washing the inside of the washing tank, wherein water supplied is provided. Receiving means for receiving water, generating means for generating alkaline ionized water from the received water, dirt detecting means for detecting dirt on the inner wall of the cleaning tank, and self-cleaning according to the detection output of the dirt detecting means. A dishwasher comprising: a washing means for automatically designating a mode and washing the inside of the washing tank with the generated alkaline ionized water.