JPH0662997A - Dishwasher - Google Patents

Abstract

PURPOSE:To prevent hot water from being drained at its original temp. to keep a drain pipe on a sink free from the damage done by the hot water by providing a temp. lowering means for lowering the temp. of the hot water upon draining from a cleaning tank. CONSTITUTION:A drain tank 8 is provided in front of the bottom part of a cleaning tank 3 and a circulating opening 9 and a drain opening 10 are formed at the lower part of the side face of the drain tank 8. A suction opening 17 of a drainage pump 16 and the drain opening 10 of the drain tank are connected by a connecting hose 18 and a drain hose 19 is connected to a discharge opening 16a of the drainage pump 16. In a hot water washing process, a water feed valve 23 is opened to feed water in the cleaning tank 3 and the washing water mixed with cold water therein is circulated and stirred by operating a cleaning pump 12 for a predetermined time. The washing water is then drained out by operating the drainage pump 16 for a predetermined time. The washing water having a high temp. is thereafter cooled and drained out little by little by the cyclic action of the water feed, stirring and water drainage as mentioned above. Finally, the drainage pump 16 alone is further operated for about one minute to pump out all of the washing water having a sufficiently lowered temp.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to dishwashers.

[0002]

2. Description of the Related Art Conventionally, in a dishwasher, there is a dishwasher in which heated water of about 70 ° C. is sprayed on dishes to kill bacteria such as Escherichia coli propagating on the dishes.
For example, JP-A-3-222929 (A47L15
/ 46).

[0003]

In the so-called built-in type dishwasher in which the main body is stored in the sink, the drain hose is directly connected to the drain pipe connected to the downstream side of the drain trap of the sink. Most of the drainage pipes of the sink are made of vinyl chloride and have a relatively low heat resistance temperature of about 60 ° C.

When used as a built-in type in this way, in a conventional dishwasher, water heated to a high temperature is directly discharged to a drain pipe made of vinyl chloride. This causes the drain pipe to overheat and expand, cracking,
As a result, water leakage may occur.

The present invention relates to an improvement of a dishwasher and solves such a problem.

[0006]

The dishwasher of the present invention comprises:
A cleaning tank disposed in the machine, a water supply means for supplying water to the cleaning tank, a draining means for draining water from the cleaning tank, and a heating means for heating water stored in the cleaning tank. A cleaning means for spraying the water heated by the heating means onto the tableware and a temperature lowering means for lowering the temperature of the heated water when the water is drained are provided.

[0007]

[Function] Since the heating water in the cleaning tank can be discharged after the water temperature is lowered by the temperature lowering means, for example, the heating water is rinsed with high-temperature heating water to kill various bacteria, and this heating water is removed. Even if it is discharged directly to the drain pipe of the sink made of vinyl chloride, the drain pipe will not overheat due to the high temperature drainage.

[0008]

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

In FIG. 5, 1 is a dishwasher of the embodiment, which is a so-called built-in type in which the main body is stored in a sink.

Reference numeral 2 is a machine frame of the dishwasher 1, and 3 is a cleaning tank provided in the machine frame 2. 4 is a door provided at the opening on the front surface of the cleaning tank 3, the lower end of which is supported,
Open to the front. Reference numeral 5 denotes an operation panel attached to the upper portion of the door 4, and an operation key group 5a for setting various cleaning operations, a driving course, and a display LE indicating a progress degree during driving.
D group 5b.

Reference numeral 6 denotes a hollow nozzle arm rotatably supported at the center of the bottom of the cleaning tank 3, and a jet port 7 is opened on the upper surface at a predetermined angle. 8 is the cleaning tank 3
It is a drainage tank formed in the front part of the bottom of the
And the drainage port 10 is opened. Reference numeral 11 is a filter attached to the upper surface of the drainage tank 8 for removing the residual vegetables that have flowed down from the tableware. Reference numeral 12 is a cleaning pump provided on the outer bottom of the cleaning tank 3, and its suction port 13 is
It is connected to the circulation port 9 of the drainage tank 8 via a connection pipe 14, and the discharge port 15 is connected to the nozzle arm 6.

A drain pump 16 is also provided at the outer bottom of the cleaning tank 3, and its suction port 17 is connected to the connecting hose 1.
It is connected to the drain port 10 of the drain tank 8 through 8. Reference numeral 19 denotes a drain hose connected to the discharge port 16a of the drain pump 16. The drain hose 19 is drawn from the outer bottom portion of the cleaning tank 3 to the rear portion of the main body, lifted upward at the rear portion, and then lowered. Is piped to. In this way, the water in the cleaning tank 3 does not flow out except when draining water, and the water that flows backward from the outside of the machine does not enter the inside of the machine. The drain hose 19 is directly connected to a drain pipe of a sink, which is mostly made of vinyl chloride, via an external connection hose or the like.

Thus, during the cleaning or rinsing process, the cleaning water or rinsing water stored in the cleaning tank 3 is introduced into the nozzle arm 6 by the cleaning pump 12, and further from the jet port 7 to the upper side thereof. It is sprayed on the tableware (not shown) arranged in, and is sucked into the cleaning pump 12 again through the drain tank 8. In this way, the washing water and the rinse water stored in the washing tank 3 are circulated and splashed on the dishes to wash the dishes.

During the drainage process, the wash water and the rinse water are discharged to the drain pipe of the sink through the drain hose 19 by the operation of the drain pump 16.

Numeral 20 is a sheathed heater disposed at the bottom of the cleaning tank 3 from the vicinity of the center to the rear thereof, which warms the cleaning water and rinse water, and raises the temperature inside the cleaning tank 3 at the time of drying for cleaning. It enhances the drying effect. Also,
Reference numeral 21 denotes a thermistor fixed to the outer bottom surface of the cleaning tank 3, which detects the temperature of the cleaning water and the rinse water.

Reference numeral 22 is a water supply nozzle installed above the rear portion of the cleaning tank 3, and 23 is an electromagnetic water supply valve connected to the water supply nozzle 22. The water of the water supply source, which is the wash water or rinse water, is opened by opening the electromagnetic water supply valve 23.
It is supplied into the cleaning tank 3 through the water supply nozzle 22.

The air sucked from the cleaning tank 3 at the time of drying is provided on the rear side of the main body and on the side portion of the drain hose 19.
A heat exchange chamber 24 is provided to allow heat to be exchanged by a heat exchange fan (not shown) provided inside to remove water, and then to be introduced into the cleaning tank 3 again.

FIG. 6 shows the control mechanism of the dishwasher,
25 is a microcomputer (hereinafter referred to as a microcomputer)
And includes a CPU 26, a RAM 27, a ROM 28, a timer-29, and the like.

The CPU 26 includes a control unit 30 and a calculation unit 3
1, the control unit 30 fetches and executes an instruction, and the arithmetic unit 31 receives data from an input device or a memory in response to a control signal from the control unit 30 in the instruction execution stage. On the other hand, arithmetic processing such as binary addition, logical operation, increase / decrease and comparison is performed. RAM 27
Is for storing data about the device,
The ROM 28 is preliminarily loaded with means for operating the device, setting conditions for determination, rules for processing various information, and the like.

The microcomputer 25 uses the operation key group 5
a, a float type reference water level switch 32 for detecting a predetermined water level, an abnormal water level switch 33 of the same type for detecting excess water supply, and an input from the A / D conversion circuit 34 connected to the thermistor 21. LED group 5
A control signal is sent to the load drive circuit 35 composed of b and the bidirectional thyristor.

The load driving circuit 35 is the microcomputer 2
According to the control signal from the control unit 5, the operation of the cleaning pump 12, the drainage pump 16, the sheath heater 20, the electromagnetic water supply valve 23, and the fan motor 36 that drives the heat exchange fan is controlled.

The A / D conversion circuit 34 converts the temperature data of the analog voltage value detected by the thermistor 21 into a digital voltage value and inputs it to the microcomputer 25. A plurality of reference values are stored in the ROM 28 in the microcomputer 25, and the microcomputer 25 compares the values input from the A / D conversion circuit 34 with these reference values to judge the water temperature in multiple stages. To do.

Now, the operation of the dishwasher of this embodiment based on the above construction will be described with reference to FIGS.

After the dishes are stored in the cleaning tank 3 and the detergent is put therein, a start switch (not shown), which is one of the operation key groups 5a, is pressed to start the cleaning process.

In this cleaning process, the microcomputer 25
First, the water supply valve 23 is opened to supply water into the cleaning chamber 3 (S1). When a predetermined water level is detected by the reference water level switch 32 (S2), water supply is stopped (S3). Then, the heater 20 is turned on and the cleaning pump 12 is rotated (S4). As a result, the cleaning water mixed with the detergent is sprayed from the nozzle arm 6 onto the dishes while being heated by the heater 20 and increasing in temperature.

Thus, when the water temperature in the cleaning tank 3 reaches 60 ° C. (S5), the microcomputer 25 causes the heater 20 to operate.
Is turned off, and the cleaning pump 12 is stopped (S
6). Then, the drainage pump 16 is rotated to perform drainage (S7). When the water level drops and the reference water level switch 32 is turned off (S8), and 20 seconds later (S9), the drainage pump 16 is stopped (S1).
0). At this time, all the cleaning water in the cleaning tank 3 is not discharged, and some remains.

Next, the rinsing step is started. In the rinsing process, first, like the cleaning process, water is supplied to a predetermined water level (S11).
~ S13). Then, the cleaning pump 12 is rotated for 1 minute (S14 to S16), and the mixed water of the cleaning water remaining in the cleaning process and the newly supplied rinse water is sprayed on the dishes. In this case, the tableware is sprayed with relatively warm mixed water, and the tableware is gradually cooled while rinsing. After that, the drainage pump 16 is rotated to perform drainage (S17). When the reference water level switch 32 is turned off (S18) and 30 seconds later (S19), the drainage pump 16 is stopped (S20). At this time, all the mixed water in the cleaning tank 3 is discharged.

After that, rinsing, that is, steps 11 to 20.
Repeat two more times. At this time, since all the water in the washing tank 3 is replaced, cold water is applied to the tableware, but since the temperature of the tableware is lowered to some extent by the first rinsing, damage due to heat shock occurs. Absent.

After rinsing three times, a hot water rinsing step is subsequently performed. First, similar to the above steps, water is supplied up to a predetermined water level (S21 to S23). Next, the heater 20
Is turned on and the cleaning pump 12 is rotated (S24). Rinse water is sprayed from the nozzle arm 6 onto the dishes until the water temperature in the cleaning tank 3 reaches 68 ° C. That is, during this rinsing, the heater 20 heats up more and more, and hot water is applied to the tableware in the latter half. As a result, various bacteria such as Escherichia coli propagating on the tableware are killed.

When the water temperature reaches 68 ° C. (S25), the heater 20 is turned off and the cleaning pump is stopped (S26).

In the dishwasher of this embodiment, the drain hose 19 is directly connected to the drain pipe of the sink. The drainage pipe of this sink is often made of vinyl chloride having a heat resistant temperature of about 60 ° C. Therefore, if the rinse water that has reached 68 ° C. is discharged as it is, the drain pipe may be overheated and expanded, and cracks may occur, resulting in water leakage.

Therefore, in the hot water rinsing step, the temperature drop drainage control is performed to drain the water by lowering the water temperature (S27).
This will be described below with reference to FIG.

First, the water supply valve 23 is opened, and water is supplied to a level at which the abnormal water level switch 33 does not reach the operating water level. Then, the cleaning pump 12 is kept for a certain time.
ON for 0.1 seconds-OFF for 0.9 seconds. Thus
The rinse water in the cleaning tank 3 to which cold water is added is circulated and stirred. Next, drainage is performed by rotating the drainage pump 16 for a certain period of time. After that, a series of operations of water supply, stirring, and drainage are repeated for a total of 1 minute. In this way, the hot rinsing water is gradually discharged while lowering the temperature.

At the time of stirring, the cleaning pump 12 is made to rotate little by little, such as ON for 0.1 second and OFF for 0.9 seconds, because the rinse water is jetted vigorously from the nozzle arm 6. This is to prevent it. That is,
This is because the water whose temperature has dropped due to the addition of cold water is hung on the tableware that has been warmed up so as not to cool the tableware.

Now, after that, only the drainage pump 16 is rotated for another minute, and all the rinse water having a sufficiently lowered temperature is discharged.

When the drainage is completed in this way, the process proceeds to the drying process. As described above, the dishwasher of the present embodiment is provided with a temperature lowering means for lowering the temperature of discharged water, and heated water having a temperature higher than the heat resistant temperature of the drain pipe of the sink connected to the drain hose of the main body, Since the temperature is lowered and the water is discharged, the drain pipe is not overheated by the high temperature drainage. Therefore, damage to the drain pipe can be prevented.

In this embodiment, the temperature of the discharged water is lowered only in the hot water rinsing step. However, in the washing step, the water temperature is similarly lowered even after washing with 60 ° C. washing water. It may be discharged by discharging.

Further, the present invention is not limited to the built-in type dishwasher, and it may be one which drains to the sink of the sink like a general dishwasher. In this case, by lowering the temperature of the water discharged to the sink, the user is not exposed to hot water, and there is no risk of causing burns or the like.

[0039]

According to the structure of the present invention, since the temperature lowering means for lowering the temperature of the discharged water is provided and the high temperature heated water can be discharged after the temperature is lowered, for example, Even if the drain hose of the equipment body is directly connected to the drain pipe of the sink with low heat resistance, the drain pipe will not be overheated and damaged.

Therefore, it is possible to provide a dishwasher which can be used with peace of mind regardless of the place where it is installed.

[Brief description of drawings]

FIG. 1 is a timing chart showing the contents of temperature drop drainage control of a dishwasher of the present invention.

FIG. 2 is a flow chart showing a cleaning process as well.

FIG. 3 is a flow chart showing a rinsing process as well.

FIG. 4 is a flow chart showing a hot water rinsing step.

FIG. 5 is a side vertical cross-sectional view showing the configuration of the dishwasher of the present invention.

FIG. 6 is a block diagram showing a control mechanism of the same.

[Explanation of symbols]

 3 Cleaning Tank 6 Nozzle Arm (Cleaning Means) 12 Cleaning Pump (Cleaning Means, Cooling Means) 16 Drain Pump (Draining Means) 20 Sheath Heater (Heating Means) 23 Electromagnetic Water Supply Valve (Water Supply Means, Cooling Means) 25 Microcomputer (Cooling Means) means)

Claims (1)

[Claims] 1. A cleaning tank disposed inside the machine, a water supply means for supplying water to the cleaning tank, a drainage means for draining water from the cleaning tank, and a water stored in the cleaning tank. A dishwasher comprising: heating means for heating; washing means for spraying water heated by the heating means onto dishes; and temperature lowering means for lowering the temperature of the heated water when draining.