JP3276944B2 - dishwasher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a dishwasher.

[0002]

2. Description of the Related Art Conventionally, in a dishwasher, when rinsing, heating water at about 70 ° C. is sprayed on dishes to kill various bacteria such as Escherichia coli that propagate on the dishes.
For example, JP-A-3-222929 (A47L15)
/ 46).

[0003]

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

When used as a built-in type as described above, in a conventional dishwasher, water heated to a high temperature is directly discharged to a drainage hose made of vinyl chloride.
As a result, the drain hose may be overheated and expanded, cracked, and as a result, water leakage may occur.

[0005] The present invention relates to an improvement in a dishwasher and eliminates such problems.

[0006]

Means for Solving the Problems and Effects of the Invention The present invention relates to a washing tank provided in an apparatus, a washing means for injecting water stored in the washing tank to tableware, and a washing tank in the washing tank. A drainage means for draining through a drainage hose, and in a rinsing subsequent to the washing, in a dishwasher in which high-temperature water is applied to the dishes and the dishes are rinsed with hot water, cold water is supplied into the washing tank. Water supply means, after the hot water rinse, before operating the drainage means to perform drainage, operating the water supply means to supply cold water into the washing tank, and supplying cold water to the dishes warmed by the hot water rinse. and a cooling means for lowering the temperature of the water reaches a higher temperature in the hot water rinse without cooling the over, this cooling means
The temperature of the water that has reached the high temperature in the boiling water
After the water is drained by the drainage means,
It shifts to the process .

In such a configuration, the water heated to a high temperature in order to kill germs in the hot water rinse is discharged after the water temperature is lowered by the temperature lowering means.
For example, when the water after rinsing with hot water is directly discharged to a drain hose of a sink made of vinyl chloride, the drain hose is not overheated by high-temperature drainage. Therefore, breakage of the drain hose due to overheating can be prevented.

[0008] In addition, since the temperature of water is lowered without cooling the tableware which has been heated by rinsing with hot water by means of a temperature lowering means without cooling the tableware, the tableware does not deteriorate. . (If the tableware is exposed to cold water during the operation of lowering the temperature of the water, the tableware that has been warmed by the hot water rinsing and that has become easy to dry becomes difficult to dry.) Further, the temperature lowering means is provided with the water supply. After operating the means and supplying cold water, the washing means is operated so as to stir the water in the washing tank without vigorously jetting water, and specifically, the washing means is operated intermittently. It is preferable that the temperature of water that has reached a high temperature in the hot water rinsing be reduced without cooling the kitchen utensils warmed by the hot water rinsing with cold water.

In such a configuration, the water is stirred by the operation of the washing means, so that the temperature of the water can be rapidly reduced. In addition, since the washing means is operated weaker than at the time of washing so as not to spray water vigorously and water is not applied to the dishes, the dishes are not cooled, and the dishes are not dried well.

[0010]

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

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

Reference numeral 2 denotes a machine frame of the dishwasher 1, and 3 denotes a washing tank provided in the machine frame 2. Reference numeral 4 denotes a door provided at an opening on the front surface of the washing 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, which includes an operation key group 5a for setting various cleaning operations, an operation course, and a display LE indicating the degree of progress during operation.
D group 5b.

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

A drain pump 16 is provided at the outer bottom of the washing tank 3 and has a suction port 17 connected to the connection hose 1.
8 is connected to a drain port 10 of the drain tank 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 out from the outer bottom of the washing tank 3 to the rear of the main body, lifted up at the rear, and then lowered downward. It is plumbed. In this manner, the water in the washing tank 3 is prevented from flowing out of the apparatus except at the time of drainage, and water flowing backward from outside the apparatus is prevented from entering the apparatus. The drain hose 19 is connected directly to a drain hose of a sink made of vinyl chloride via an external connection hose or the like.

In the washing or rinsing step, the washing water or the rinsing water stored in the washing tank 3 is introduced into the nozzle arm 6 by the washing pump 12 and is further discharged from the jet port 7 to the upper side. And is sucked into the cleaning pump 12 again through the drainage tank 8. In this way,
The dishes are washed by circulating the washing water and the rinsing water stored in the washing tank 3 while circulating the dishes.

During the draining step, the washing water and the rinsing water are discharged to the drain hose of the sink through the drain hose 19 by the operation of the drain pump 16.

Numeral 20 denotes a sheath heater disposed behind the bottom of the washing tank 3 for warming the washing water and the rinsing water.
At the time of drying, the inside of the washing tank 3 is heated to enhance the washing / drying effect. Reference numeral 21 denotes a thermistor fixed to the outer bottom surface of the washing tank 3, which detects the temperature of the washing water and the rinsing water.

Reference numeral 22 denotes a water supply nozzle installed above the rear part of the washing tank 3, and reference numeral 23 denotes an electromagnetic water supply valve connected to the water supply nozzle 22. The water of the water supply source serving as the washing water and the rinsing water is opened by opening the electromagnetic water supply valve 23,
The water is supplied into the cleaning tank 3 through the water supply nozzle 22.

The air sucked from the washing tank 3 during drying is applied to the rear of the main body and to the side of the drain hose 19.
A heat exchange chamber 24 is provided for exchanging heat with a heat exchange fan (not shown) provided therein to remove water and then introducing the moisture into the cleaning tank 3 again.

FIG. 6 shows a control mechanism of the dishwasher according to the present embodiment. Reference numeral 25 denotes a microcomputer (hereinafter referred to as a microcomputer), which includes a CPU 26, a RAM 27, and a ROM 2.
8, a timer 29 and the like.

The CPU 26 includes a control unit 30 and a calculation unit 3
The control unit 30 fetches and executes an instruction, and the arithmetic unit 31 transmits data provided from an input device or a memory by a control signal from the control unit 30 in an instruction execution stage. Then, arithmetic processing such as binary addition, logical operation, increase / decrease, and comparison is performed. The RAM 27
Is for storing data about the device,
The ROM 28 is for reading in advance means for operating the apparatus, setting of conditions for determination, rules for processing various information, and the like.

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

The load drive circuit 35 includes the microcomputer 2
In accordance with the control signals from 5, the operation of the cleaning pump 12, the drain pump 16, the sheath heater 20, the electromagnetic water supply valve 23, and the fan motor 36 for driving 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 the digital voltage value 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 determine the water temperature in multiple stages. .

The operation based on the above configuration will now be described with reference to FIGS.

After the dishes are accommodated in the washing tank 3 and a detergent is introduced, when a start switch (not shown), which is one of the operation keys 5a, is pressed, a washing step is first started.

In this cleaning step, 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), the water supply is stopped (S3). Then, the heater 20 is turned on, and the cleaning pump 12 is rotated (S4). As a result, the washing water mixed with the detergent is jetted from the nozzle arm 6 to the tableware while being heated by the heater 20 to increase the temperature.

When the water temperature in the cleaning tank 3 reaches 60 ° C. (S5), the microcomputer 25 sets the heater 20
Is turned off, and the washing pump 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 after 20 seconds have passed (S9), the drain pump 16 is stopped (S1).
0). At this time, all the washing water in the washing tank 3 is not discharged, and some remains.

Next, a rinsing step is started. In the rinsing step, first, water is supplied to a predetermined water level as in the cleaning step (S11).
To S13). Then, the washing pump 12 is rotated for one minute (S14 to S16), and the mixed water of the washing water remaining in the washing step and the newly supplied rinse water is sprayed on the tableware. Thus, rinsing with relatively warm mixed water and gradually cooling the dishes. Thereafter, the drainage pump 16 is rotated to perform drainage (S17). When the reference water level switch 32 is turned off (S18), and 30 seconds thereafter elapse (S19), the drain pump 16 is stopped (S20). At this time, all the mixed water in the washing tank 3 is discharged.

Thereafter, rinsing, that is, steps 11 to 20
Is repeated twice. At this time, since all the water in the washing tank 3 is replaced, cold water is applied to the tableware. However, since the temperature of the tableware is lowered to some extent by the first rinse, breakage due to heat shock occurs. Absent.

After the three rinsings, a hot water rinsing step is performed.

First, water is supplied to a predetermined water level as in the above steps (S21 to S23). Next, the heater 20 is turned on.
And the cleaning pump 12 is rotated (S2
4). Rinsing water is sprayed from the nozzle arm 6 onto the dishes until the water temperature in the washing tank 3 reaches 68 ° C. That is, during this rinsing, the heater 20 heats more and more, and in the latter half, hot water is applied to the tableware.
This kills various bacteria such as Escherichia coli that propagate on the tableware.

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 hose of the sink. The drain hose of the sink is often made of vinyl chloride having a heat-resistant temperature of about 60 ° C. Therefore, if the rinsing water that has reached 68 ° C. is directly discharged, the drain hose may be overheated and expanded due to overheating, which may cause cracks, resulting in water leakage.

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

First, the water supply valve 23 is opened, and water is supplied to such an extent that the water level at which the abnormal water level switch 33 operates is not reached. Then, the cleaning pump 12 is turned on for a certain time,
Operate for 0.1 seconds ON-0.9 seconds OFF. Thus,
The rinsing water in the washing tank 3 to which the cold water is added is circulated and stirred. Next, drainage is performed by rotating the drainage pump 16 for a certain period of time. Thereafter, the same operation as water supply-stirring-drainage is further repeated for a total of one minute. As a result, the high-temperature rinse water is gradually discharged at a lower temperature.

Here, the reason why the washing pump 12 is rotated little by little so as to be ON for 0.1 second and OFF for 0.9 second during stirring is that rinsing water is jetted vigorously from the nozzle arm 6. This is to prevent them from doing so. That is,
This is because the water whose temperature has dropped due to the addition of cold water is hung on the warmly cooked tableware so as not to cool the tableware.

After that, only the drain pump 16 is further rotated for one minute to discharge all the rinse water whose temperature has sufficiently decreased.

When the drainage is completed, the process proceeds to the drying step.

As described above, the dishwasher of the present embodiment is provided with the temperature lowering means for lowering the temperature of the water to be discharged, and is provided with a heating device having a temperature higher than the heat resistant temperature of the drain hose of the sink connected to the drain hose of the main body. Since the water is discharged after the temperature is lowered, the drain hose is not overheated by the hot drain water. Therefore, breakage of the drain hose can be prevented.

The present invention is not limited to the built-in type dishwasher, but may be a type in which water is drained to a sink of a sink like a general dishwasher. In this case, by lowering the temperature of the water discharged to the sink, the user does not get hot water, and there is no risk of causing burns or the like.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a washing process of a dishwasher according to the present invention.

FIG. 2 is a flowchart showing a rinsing step.

FIG. 3 is a flowchart showing a hot water rinsing step.

FIG. 4 is a program chart showing the contents of the cooling water discharge control.

FIG. 5 is a side longitudinal sectional view showing the configuration of the dishwasher of the present invention.

FIG. 6 is a block diagram showing a control mechanism.

[Explanation of symbols]

 3 Cleaning Tank 6 Nozzle Arm (Cleaning Means) 12 Cleaning Pump (Cleaning Means) 16 Drain Pump (Draining Means) 23 Electromagnetic Water Valve (Water Supply Means) 25 Microcomputer (Cooling Means)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) A47L 15/46 A47L 15/42

Claims (3)

(57) [Claims] 1. A washing tank provided in a machine, washing means for injecting water stored in the washing tank to tableware, and drain means for draining water from the washing tank through a drain hose. In the rinsing subsequent to the washing, in a dishwasher for rinsing the dishes with hot water by rinsing the dishes with hot water, a water supply means for supplying cold water into the washing tank, and after the hot water rinsing, the drainage Before operating the means to perform drainage, the water supply means is operated to supply cold water into the washing tank, and the tableware warmed by the hot water rinse is cooled with hot water without being cooled by high temperature in the hot water rinse. and a cooling means for lowering the temperature of the water reached, the cooling means
The temperature of the water that has reached a high temperature in the hot water rinse
After decreasing the degree, the drainage by the drainage means ends
And a dishwasher characterized by shifting to a drying process . 2. The temperature lowering means operates the water supply means to supply cold water, and then operates the cleaning means to stir the water in the cleaning tank without vigorously jetting water. 2. The dishwasher according to claim 1, wherein the temperature of the water that has reached a high temperature in the hot water rinse is reduced without cooling the dishes heated by the hot water rinse with cold water. 3. The temperature lowering means operates the water supply means to supply cold water, and then operates the washing means intermittently, without cooling the tableware warmed by the hot water rinsing with cold water. The dishwasher according to claim 1, wherein the temperature of the water that has reached a high temperature in the hot water rinse is reduced.