JPH05220083A - Dish washer - Google Patents

Abstract

PURPOSE:To prevent the overflowing of a washing water from a tank of a dish washer according to turning ON or OFF of a power source switch. CONSTITUTION:A dish washer repeats one cycle of process comprising a water supply process, washing or rinsing process and a drain process by control with a controller when a power source switch is turned ON. When an overflow switch 33b is turned ON as a washing water in a tank 20a exceeds an overflow level higher than a reference water level a control circuit makes a drain pump 32 operate to drain a washing water in the tank outside the machine. When a dish washer is at rest with the power source switch OFF, upon the turning ON of a reference level switch 33a as the washing water in the tank exceeds the reference water level, the control circuit makes the drain pump operate to drain the washing water in the tank outside the machine. While the power source switch is OFF, the detection of the water level is accomplished with an overflow switch when the reference water level switch breaks down.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dishwasher, and more particularly to a dishwasher having means for preventing overflow of wash water from a tank to the outside of the dishwasher.

[0002]

2. Description of the Related Art Conventionally, as shown in, for example, Japanese Patent Application Laid-Open No. 3-118017, this type of dishwasher reaches an overflow water level which is the water level immediately before the wash water in the tank overflows from the tank. When the overflow water level detection means detects this, the control device activates the drainage means regardless of whether the power switch is on or off to discharge the wash water in the tank to an appropriate place outside the machine to prevent overflow of the wash water. ing.

[0003]

However, in the dishwasher, the operation of the drainage means is controlled by the overflow water level which is the water level immediately before the wash water overflows from the tank. Alternatively, the drainage operation may be delayed due to a malfunction of the overflow water level detection means, which may cause the wash water to overflow to the outside of the tank. At this time, if the dishwasher is in operation and is being monitored by the operator, this is not a problem, but if the dishwasher is stopped and not being monitored by the operator, overflow of washing water is a problem. become. On the other hand, if the overflow water level is set too low, for example, near the reference water level,
During normal operation of the dishwasher, the wash water often reaches the overflow level and activates the drainage means, which interferes with the original operation of the dishwasher.

In the dishwasher, the power switch is often in the off state rather than the on state.
If the overflow water level detection means fails in an off state that is not normally monitored by the operator, a large amount of overflow water is likely to occur. The present invention is intended to solve the above problems, and an object thereof is to provide a dishwasher capable of appropriately preventing overflow of wash water from a tank according to the on / off state of a power switch. And

[0005]

In order to achieve the above object, the structural feature of the invention according to claim 1 is that the wash water at a predetermined temperature is supplied to an external water supply source in a tank 1a provided in the wash chamber 1. Water supply means 2a to be supplied from the above, washing and rinsing means 2b for rinsing and rinsing the tableware 1b housed in the washing chamber 1 by circulating the washing water in the tank 1a into the washing chamber 1 The drainage means 2c for discharging the wash water stored in the tank 1a upon completion of the washing or rinsing of 2b, and the respective means are sequentially operated according to the ON state of the power switch 3 to supply water, wash or rinse. And a control means 4 for repeatedly performing one cycle of a drainage process,
Reference water level detection means 5 for detecting the reference water level of the wash water in the tank 1a, overflow water level detection means 6 for detecting the overflow water level higher than the reference water level, and overflow water level detection means when the power switch 3 is in the ON state. Drainage control for operating the drainage means 2c according to the detection of the overflow water level by 6 and controlling the drainage means 2c according to the detection result of the reference water level by the reference water level detection means 5 when the power switch 3 is in the off state. And means 7 are provided.

Further, the structural feature of the invention according to claim 2 is that the dishwasher according to claim 1 is further provided with a failure determining means 8 for determining whether or not there is a failure in the reference water level detecting means 5. When the power supply switch 3 is in the OFF state and the failure determination means 8 determines that there is a failure, the drainage control means 7 controls the operation of the drainage means 2c according to the overflow water level detection result of the overflow water level detection means 6. This is because the water level detection switching means 9 for performing the operation is provided.

[0007]

In the invention according to claim 1 configured as described above, when the power switch 3 is on, the water level of the wash water reaches an overflow water level higher than the reference water level due to an abnormality of the dishwasher. Flood level detector 6 only when
Detects this, and in response to this, the drainage control means 7 operates the drainage means 2c to discharge the wash water to a proper place outside the machine.
Further, when the power switch 3 is off, the reference water level detection means 5 detects this when the water level of the wash water reaches a reference water level lower than the overflow water level, and the drainage control means 7 receives the detection result and the drainage control means 7 drains the drainage means 2c. To discharge the wash water.
As a result, when the power switch 3 is on, it is possible to prevent overflow without disturbing the normal operation of the dishwasher, and when the power switch 3 is off, there is a margin before the wash water reaches the overflow level. You can have it to prevent flooding.

In the invention according to claim 2 configured as described above, when the power switch 3 is off,
The failure determination means 8 determines whether or not the reference water level detection means 5 has a failure. When it is determined that the reference water level detection means 5 is out of order, the water level detection switching means 9 switches the water level detection from the reference water level detection means 5 to the overflow water level detection means 6. Then, the drainage control means 7 operates the drainage means 2c according to the detection result of the overflow water level by the overflow water level detection means 6 to discharge the wash water to a proper place outside the machine. As a result, in the invention described in claim 2, in addition to the effect of the invention described in claim 1, even when the reference water level detecting means 5 fails, the overflow water level detecting means 6 causes the flush water level to rise. Since it is possible to detect the rise of the water and drain the water, it is possible to reliably prevent a large amount of water overflowing from the tank 1a when the power switch 3 is turned off.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the drawings, and FIG. 2 schematically shows the entire dish washer.
This dishwasher has a box-shaped housing 10 and a box-shaped washing tank 20 integrally mounted inside the housing 10. This cleaning tank 20
The inside is configured as a cleaning chamber R, a tank 20a for storing cleaning water is provided at the bottom, and the front surface of the cleaning tank 20 is opened and closed by a door 21. By opening and closing this door 21, tableware 23 placed on the rack 22
Can be put in and taken out of the washing room R. On the back wall 20b of the cleaning tank 20, a supply pipe Q having a water supply valve 26 interposed
₆ is attached, the water supply valve 26 is opened by the excitation of the electromagnetic solenoid 26a, and high-temperature cleaning water from an external water supply source (not shown) is passed through the cleaning chamber R to the tank 20a.
Supply in.

A supply pipe Q ₁ is connected to the bottom of the tank 20a. The supply pipe Q ₁ is branched midway and connected to the suction side of the cleaning pump 31 and the drainage pump 3
2 is connected to the suction side. Further, the supply pipe Q ₁ is located at an intermediate portion between the cleaning pump 31 and the drainage pump 32, and the supply pipe Q ₂
It is connected to the sub tank 33 via.

The cleaning pump 31 is connected to a lower cleaning nozzle 24 attached to the bottom wall of the cleaning tank 20 via a supply pipe Q ₃ connected to the discharge side, and branched from the supply pipe Q ₃ for cleaning. Upper cleaning nozzle 2 attached to the upper wall of cleaning tank 20 via supply pipe Q ₄ extending above tank 20
5, the operation is started by driving the electric motor 31a shown in FIG. 3, and the cleaning water in the tank 20a is sucked and pressure-fed to the upper cleaning nozzle 25 and the lower cleaning nozzle 24.
The drainage pump 32 is connected at its discharge side with a supply pipe Q ₅ extending to a proper place outside the machine, and starts its operation by driving the electric motor 32a shown in FIG. 3 to suck the cleaning water in the tank 20a. And discharge it to the proper place outside the machine.

The sub-tank 33 has a tank 2 at the bottom thereof.
0a, and contains a reference water level switch 33a and an overflow switch 33b inside. The reference water level switch 33a detects that the water level of the wash water supplied into the tank 20a has reached a reference water level x _o , which is a height required for washing, etc., by opening the water supply valve 26. When the height is higher than the reference water level x _o , it is turned on, and when the height of the water surface is lower than the reference water level x _o , it is turned off. In addition, the overflow switch 33b is set to the standard water level x _o.
It is higher and detects the overflow water level x _I that defines the height of the water surface immediately before the flush water in the tank 20a overflows to the outside of the machine. If the height of the water surface is higher than the overflow water level x _I , it is turned on. And the height of the water surface is lower than the overflow water level x _I , it is in the off state. A drier 27 including a heater and a fan is attached to the back wall 20b of the washing tank 20, and hot blast is blown to the dishes which have been rinsed to dry them.

Next, an electric control device for electrically controlling the dishwasher configured as described above will be described with reference to the drawings. FIG. 3 shows a circuit diagram of the device.
This electric control device has two input buses L ₁ and L ₂ , and an electric motor 31 a of the washing pump 31 and an electric motor 32 a of the drainage pump 32 are provided on the input buses L ₁ and L _2.
An electromagnetic solenoid 26a of the water supply valve 26 and a dryer 27
And a control circuit 40 for controlling energization of each of these electric motors, solenoids and dryers, and a coil X of a relay 42.
₁ and the power switch 41 are connected. The input buses L ₁ and L ₂ are connected to a single-phase commercial power source with the bus L ₂ on the ground side, and the input buses L ₁ and L ₂ are set to 120 v.

Electric motor 31a, electromagnetic solenoid 26a
And one end of the dryer 27 has a contact 41 of a power switch 41.
is connected to the input bus L ₁ via a, and the motor 31a,
The other end of the solenoid 26a and the drier 27 is a control circuit 40.
Is connected to the output side of. The power switch 41 has a contact 41a that can be manually turned on / off, is connected to the output side of the control circuit 40 at one end, and is connected to the contact 41 at the other end.
It has an electromagnetic solenoid 41b connected to one end of a. The contact 41a of the power switch is connected to the control circuit 4
Electromagnetic solenoid 41 excited by output signal from 0
It can be switched from on to off by b. One end of the electric motor 32a is directly connected to the input bus L _1, and the other end of the motor 32a is connected to the output side of the control circuit 40. The coil X _{1 of the} relay 42 is connected at one end to the input bus L ₁ via the power switch 41, and the other end of the coil X ₁ is connected to the input bus L ₂ . The control circuit 40 receives a commercial voltage from a single-phase commercial power source (not shown) connected to the input buses L ₁ and L ₂ as a power switch 41.
It is supplied regardless of the on / off of
The control circuit 40 operates by supplying this commercial voltage.

The control circuit 40 includes a CPU, ROM, RA
M, interrupt timer, first timer, second timer, I / O
4 to FIG. 8 corresponding to the flowchart shown in FIG. 4 to FIG. 8 is continuously executed, and the interrupt command from the interrupt timer corresponds to the flowchart of FIG. The executed "flood interrupt program" is executed by interruption. A normally open contact x ₁₁ of the relay 42, the reference water level switch 33a and the overflow switch 33b are also connected to the input side of the control circuit 40. The normally open contact x ₁₁ of the relay 42 is turned on by energizing the coil X ₁ , and outputs a signal indicating that the power switch 41 is turned on.

Next, the operation of the embodiment configured as described above will be described. With the common conductors L ₁ and L ₂ connected to the power source, the control circuit 40 starts executing the “main program” in step 100 of FIG. After the execution of this "main program" is started, the control circuit 40 executes step 1
At 01, initial setting processing for setting various variables to initial values is executed. After the initialization process, the control circuit 40 proceeds to step 10
At 2, it is determined whether or not the power switch 41 is turned on. The rack 22 in which the dishes to be washed are placed in the washing room R
When the power switch 41 is turned on after the housing is accommodated, the control circuit 40 performs the process of the water supply routine in step 103 based on the determination of “YES” in step 102.

The control circuit 40 starts the water supply routine shown in FIG. 5 at step 120, and when the power switch 41 is turned on, the coil X ₁ of the relay 42 is excited and the normally open contact x ₁₁ is generated.
In response to the fact that the water was turned on, in step 121 the water supply valve 2
The electromagnetic solenoid 26a of No. 6 is energized to open the water supply valve 26, and the high-temperature clean cleaning water from the water supply source is supplied to the tank 20a through the cleaning chamber R. When the wash water reaches the predetermined reference water level x _o and the reference water level switch 33a is turned on, the control circuit 40 shifts the program to step 123 based on the judgment of "YES" at step 122, and at step 123 the water supply valve. Is closed, and the processing of the water supply routine is ended in step 124.

Next, the control circuit 40 advances the program to step 104 to perform the cleaning routine. The control circuit 40 starts the cleaning routine shown in FIG. 6 in step 130, sets the first timer to 2 minutes in step 131, and starts the first timer in step 132. Simultaneously with the start of the first timer, the electric motor 31a is energized, the cleaning pump 31 sucks the cleaning water containing the detergent in the tank 20a, pressure-feeds it to the upper and lower cleaning nozzles 24, 25, and ejects from the respective cleaning nozzles 24, 25. Cleaning of the tableware 23 is started by the cleaning water. After 2 minutes, the first
When the timer counts up, the control circuit 40 determines “YES” in step 134, stops energizing the electric motor 31a in step 135, and ends the cleaning routine process in step 136.

Next, the control circuit 40 executes a drainage routine process at step 105. The control circuit 40 starts the drainage routine shown in FIG. 7 in step 140, sets the second timer to 30 seconds in step 141, and starts the second timer in step 142. At the same time as the start of the second timer, the electric motor 32 is started in step 143.
When a is energized, the drainage pump 32 discharges the dirty cleaning water in the tank 20a to appropriate places outside the machine through the supply pipes Q ₁ and Q ₅ . After the elapse of 30 seconds, when the second timer counts up, the control circuit 40 determines “YES” in step 144, stops energizing the electric motor 32a in step 145, and executes the drainage routine processing in step 146. To finish.

Next, the control circuit 40 executes the water supply routine in step 106 in the same manner as in step 103 to supply clean washing water into the tank 20a, and then in step 1
At 07, as shown in FIG. 8, the rinse routine including steps 150 to 156 is executed for 30 seconds similarly to the cleaning routine of step 104. After the completion of the rinsing routine, the control circuit 40 executes the draining routine in step 108 in the same manner as in step 105 to discharge the cleaning water to a proper place outside the machine.

Further, the control circuit 40 starts from step 109.
In 111, the water supply, rinse, and drain routines executed in steps 106 to 108 are repeatedly executed,
Sufficiently rinse the tableware 23. Then, after the drainage routine ends in step 111, the control circuit 4
0 starts energizing the dryer 27 in step 112,
The hot air from the dryer 27 is blown into the washing chamber to dry the dishes 23 which have been rinsed. After the completion of the drying, the control circuit 40 outputs an off signal to the electromagnetic solenoid 41b in step 113 to turn off the power switch 41, and then shifts the program to step 102 to execute steps 102 to 113 below. repeat.

During execution of the above "main program",
The control circuit 40 interrupts and executes the "overflow interrupt program" shown in FIG. 9 about every 10 msec by the action of the interrupt timer. This "overflow interrupt program" is started in step 160 of FIG.
At 61, it is determined whether the power switch 41 is on.
Since the dishwasher is currently in operation, the control circuit 40 shifts the program to step 162 based on the determination of "YES" to determine whether or not the overflow switch 33b is on. Normally, since the water level of the wash water in the tank 20a is equal to or lower than the reference water level x _o , the control circuit 40 determines “NO” in step 162, and ends the execution of the program in step 163.

On the other hand, due to an abnormality of the dishwasher, the tank 20
When the water level in a becomes equal to or higher than the overflow water level x _I , the control circuit 40
Determines “YES” in step 162, and executes step 1
At 64, an off signal is output to the electromagnetic solenoid 41b to turn off the power switch 41, and the processing of the water supply routine, the cleaning routine, or the rinse routine is stopped. Then, in step 165, the control circuit 40 executes the drainage routine shown in FIG. 7, operates the drainage pump 32 for about 30 seconds to discharge the wash water in the tank 20a to a proper place outside the machine, and then to step 163. Ends the program execution.

Next, when the dishwasher is not operating, the power switch 41 is off, so the control circuit 40
Based on the judgment of “NO” in step 161, the program shifts to step 166 and the reference water level switch 3
It is determined whether 3a is on. When there is no abnormality in the dishwasher and the water level in the tank is below the reference water level x _o, naturally it is also below the overflow water level x _I , so the control circuit 40 executes step 1
Based on the judgment of "NO" at 66 and step 167, the execution of the program is ended at step 163. Then, when the water level of the tank 20a becomes equal to or higher than the reference water level x _o due to the abnormality of the dishwasher, the reference water level switch 33a is turned on and the ON signal is output to the control circuit 40. In response to this, the control circuit 40 determines “YES” in step 166, executes the drainage routine shown in FIG. 7 in step 168, energizes the electric motor 32a, and operates the drainage pump 32 for about 30 seconds. The wash water in the tank 20a is discharged to a proper place outside the machine, and in step 163, the execution of the program ends.

Further, due to an abnormality of the dishwasher, the tank 2
If the reference water level switch 33a is out of order when the water level at 0a exceeds the reference water level x _o , the reference water level switch 3
Since 3a does not output the ON signal to the control circuit 40, it is determined as "NO" in step 166, but when the water level of the wash water further rises and becomes equal to or higher than the overflow water level x _I , the overflow switch 33b detects this. Then, the ON signal is output to the control circuit 40. In response to this, the control circuit 40 proceeds to step 167.
Step 1 of the program based on the judgment of "YES"
In step 169, the drainage routine shown in FIG. 7 is executed, the electric motor 32a is energized, the drainage pump 32 is operated for about 30 seconds, and the wash water in the tank 20a is discharged to an appropriate place outside the machine. Then, in step 163, the execution of the program ends.

As described above, during the operation of the dishwasher, when the water level in the tank reaches the overflow water level x _I which is equal to or higher than the reference water level x _o due to the abnormality of the dishwasher, the drain pump 32 cleans the water. Since the water is discharged to a proper place outside the machine, it prevents the water from overflowing from the tank, and the water level at the start of drainage is the overflow water level x above the standard water level x _o.
By was _I, nor interfere with since drainage during normal operation nor performed operation of the dishwasher of the dishwasher.

Since it is not necessary to consider the operation of the dishwasher while the dishwasher is stopped, the drainage start standard is set to a standard water level lower than the overflow water level for an increase in the water level in the tank due to an abnormality of the dishwasher. By doing so, even if the drainage is slightly delayed due to malfunction of the drainage pump or the overflow switch, it is possible to prevent the flushing water from overflowing out of the tank with a sufficient margin.

Further, when the reference water level switch fails while the dishwasher is stopped, an increase in the water level in the tank is detected by the overflow switch, and when the water level in the tank becomes higher than the overflow water level, Since the water is drained by the drainage pump, it is possible to more reliably prevent a large amount of water overflowing from the tank while the washing machine, which is not monitored by the operator, is stopped.

[Brief description of drawings]

FIG. 1 is a claim correspondence diagram corresponding to the configuration of the present invention described in the claims.

FIG. 2 is a schematic vertical sectional side view of a dishwasher according to an embodiment of the present invention.

FIG. 3 is a diagram showing a control circuit of the dishwasher.

FIG. 4 is a flowchart of a “main program” executed by the control circuit of FIG.

5 is a flow chart showing the water supply routine of FIG. 4 in detail.

FIG. 6 is a flow chart showing the cleaning routine of FIG. 4 in detail.

FIG. 7 is a flowchart showing the drainage routine of FIG. 4 in detail.

FIG. 8 is a flow chart showing the rinse routine of FIG. 4 in detail.

9 is a flowchart of a "flooding interrupt program" executed by the control circuit of FIG.

[Explanation of symbols]

20a ... tank, 22 ... rack, 23 ... tableware, 24,
25 ... Washing nozzle, 26 ... Water supply valve, 31 ... Washing pump,
32 ... Drain pump, 33a ... Standard water level switch, 33b
... flood switch, 40 ... control circuit, 41 ... power switch, 42 ... relay, R ... washing room.

Claims (2)

[Claims] 1. A water supply means for supplying cleaning water having a predetermined temperature from an external water supply source into a tank provided in the cleaning chamber, and the cleaning water in the tank is circulated and supplied into the cleaning chamber and housed in the cleaning chamber. Washing and rinsing means for washing or rinsing tableware, draining means for discharging the washing water stored in the tank at the end of washing or rinsing of the washing and rinsing means, and power switch depending on the ON state In a dishwasher equipped with a control means for sequentially operating each of the above means to repeatedly perform one cycle of a water supply step, a washing or rinsing step, and a draining step, the washing water in the tank reaches a reference water level. And a reference water level detecting means for detecting that the wash water in the tank has reached an overflow water level higher than the reference water level. When the power switch is in the ON state, the drainage means is operated according to the overflow water level detection result of the overflow water level detection means, and when the power switch is in the OFF state, the reference water level detection result of the reference water level detection means is determined. And a drainage control means for controlling the drainage means to operate. 2. The dishwasher according to claim 1, further comprising: failure determination means for determining whether or not the reference water level detection means has a failure; and the failure determination means when the power switch is off. When it is determined that there is a failure, water level detection switching means for causing the operation control of the drainage means by the drainage control means to be performed according to the detection result of the overflow water level by the overflow water level detection means. Characteristic dishwasher.