JPH05261056A - Tableware washing machine - Google Patents

Abstract

PURPOSE:To supply washing water of a proper temperature into a tank without executing waste of washing water, etc. CONSTITUTION:A feed water valve 27 is opened and supply of washing water is started through a hot water supply device 28 from an external feed water source to the inside of a tank 21 provided in a washing tank 20. After a prescribed time elapses from the time of starting feed water, a temperature sensor 21b detects a temperature of washing water stored in the tank 21, and when its detected temperature is below a prescribed temperature, a drain pump 32 drains washing water stored in the tank to the outside of the machine for a prescribed time under the control of a drain control means. The water quantity stored in the tank in a prescribed time and the water quantity discharged in a prescribed time are determined smaller than the water quantity stored until it reaches a reference water level X0 in the tank, therefore, as a result, useless drain is decreased, and also, washing water of a proper temperature being above the prescribed temperature, and also, being not too high can be stored in the tank.

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 control device for adjusting the temperature of washing water in a tank to an appropriate temperature.

[0002]

2. Description of the Related Art Conventionally, a dishwasher of this type is installed in a tank after the supply of washing water to the tank by a water supply device is completed, as disclosed in, for example, Japanese Patent Application Laid-Open No. 3-131221. The temperature of the stored cleaning water is detected by a temperature sensor, and when the detected temperature is lower than a specified temperature, the drainage pump discharges it all out of the machine, and then the cleaning water is supplied again into the tank. The temperature is controlled so that the temperature becomes higher than a predetermined temperature.

Further, in addition to the above, this dishwasher is
Water is supplied while the temperature of the wash water is detected by the temperature sensor, and at the same time, the wash water is discharged outside the machine by the drain pump until the wash water reaches or exceeds the predetermined temperature so that the temperature of the wash water becomes equal to or higher than the predetermined temperature. Have control over.

[0004]

However, in the former case, the temperature of the wash water supplied from the water supply device at the start of the water supply is low, so that even when the wash water reaches or exceeds the predetermined temperature during the supply. When the temperature of the wash water at the end of the water supply is lower than the predetermined temperature, all the wash water supplied to the tank has to be discharged, so that a large amount of wash water is wasted. Further, since the temperature of the wash water supplied after all the wash water in the tank is discharged becomes considerably higher than a predetermined temperature, there is a problem that heating energy is wasted in the water supply device.

Further, in the latter case described above, since the cleaning water is supplied and discharged at the same time, the cleaning water is hardly stored in the tank. Therefore, the temperature sensor mounted on the outer wall of the tank causes the temperature of the cleaning water to rise. There is a problem in that it is difficult to accurately detect. Furthermore, as in the latter case, when draining the wash water at the same time while supplying it, the drainage pump discharges more water than the water supply device, so the drainage pump will run dry. There is also the problem of damaging the drain pump. The present invention is intended to solve the above problems, and an object of the present invention is to provide a dishwasher that supplies wash water at an appropriate temperature into a tank without wasting wash water or the like.

[0006]

In order to solve the above-mentioned problems, the structural feature of the invention according to claim 1 is that the cleaning water is supplied from an external water supply source through a water heater to the tank provided in the cleaning tank. A water supply device that supplies the water, a cleaning device that circulates the cleaning water in the tank into the cleaning tank to clean or rinse the dishes stored in the cleaning tank, and the cleaning stored in the tank. Tableware provided with a drainage device for discharging water and an electric control device for controlling the operations of the water supply device, the cleaning device, and the drainage device to repeatedly perform one cycle of a water supply process, a cleaning rinsing process, and a drainage process In the washing machine, in the electric control device, a temperature sensor for detecting the temperature of the wash water supplied to the tank, and after a lapse of a predetermined time from the start of water supply by the water supply device, from the temperature sensor Enter the temperature detection result is that the same temperature detection result is provided a discharge control device for controlling so as to discharge a certain time the washing water in the tank by the drainage device when less than the predetermined temperature.

Further, the structural feature of the invention according to claim 2 is that in the dishwasher according to claim 1, the tank is configured such that a part of a bottom wall of the cleaning tank is projected downward. The temperature sensor is disposed on the protruding portion.

[0008]

According to the invention as described above, the drainage control device is detected by the temperature sensor after a lapse of a predetermined time from the start of supplying the wash water by the water supply device. The temperature detection result of the wash water stored in the tank is input, and when the temperature detection result is lower than the predetermined temperature, the drainage device is operated to discharge the wash water in the tank out of the machine for a certain period of time. The amount of washing water stored in the tank within the predetermined time is smaller than the amount of water fully stored in the tank due to the end of supply, and the amount of water discharged in the fixed time is also smaller than the amount of stored water. ..

As a result, it is possible to store the wash water of a predetermined temperature or higher in the tank while reducing the wasteful discharge of the wash water. Further, by reducing the discharge of the wash water, it is possible to efficiently use the energy for heating the wash water, and it is possible to obtain the wash water at a proper temperature which is not lower than the predetermined temperature and not too high. Furthermore, since the drainage device discharges the wash water below the predetermined temperature after the predetermined amount of wash water is stored in the tank, the drainage device does not run idle, and therefore the drainage device is not damaged. Absent.

According to the invention described in claim 2 as described above, the cleaning water is stored in the tank provided by projecting a part of the bottom wall of the cleaning tank downward. In this state, since the temperature of the wash water can be detected by the temperature sensor arranged on the protruding portion, an accurate temperature detection result can be obtained. As a result, the drain control device accurately determines whether to drain water.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows the entire dishwasher.
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 room R and the bottom wall 20a
The tank 21 is formed by projecting a part of the lower part downward and making the horizontal area of the protruding portion 21a smaller than the horizontal area of the bottom wall 20a so that water can be stored in the protruding portion 21a. The front surface of the cleaning tank 20 is opened and closed by a door 22, and by opening and closing the door 22, the dishes 24 placed on the rack 23 can be taken in and out of the cleaning chamber R. .. It mounted supply pipe Q ₆ interposed in the water supply valve 27 to the rear wall 20b of the cleaning tank 20,
Further, a water heater 28 such as a gas instantaneous water heater is provided on the supply pipe Q ₇ upstream of the water supply valve 27. Water valve 27
Is supplied with water from the water supply source (not shown) and heated by the water heater 28 and is supplied to the tank 21 through the cleaning chamber R when the electromagnetic solenoid 27a is excited.

A temperature sensor 21b for detecting the temperature of the washing water supplied into the tank is attached to the outer wall of the tank 21. The temperature sensor 21b is turned on when the temperature of the washing water is 60 ° C. or higher, and turned off when the temperature is lower than 60 ° C.

At the bottom of the tank 21, a supply pipe Q ₁
Is connected, and this supply pipe Q ₁ branches in the middle,
It is connected to the suction side of the washing pump 31 and to the suction side of the drainage pump 32. Further, the supply pipe Q ₁ is connected to the sub-tank 33 via the supply pipe Q ₂ at an intermediate portion between the cleaning pump 31 and the drainage pump 32.

The cleaning pump 31 is connected to the lower cleaning nozzle 25 attached to the bottom wall 20a of the cleaning tank 20 via a supply pipe Q ₃ connected to the discharge side, and the supply pipe Q ₃ is also provided.
Supply pipe Q ₄ branched from ₃ and extended above the cleaning tank 20
It is connected to the upper side washing nozzle 26 attached to the upper wall 20c of the washing tank 20 via. Then, the cleaning pump 31 starts its operation by driving the electric motor 31a shown in FIG. 2, sucks the cleaning water in the tank 21 and sends it to the lower cleaning nozzle 25 and the upper cleaning nozzle 26 under pressure. The drainage pump 32 is connected at its discharge side to a supply pipe Q ₅ extending to a proper place outside the machine, starts its operation by driving the electric motor 32a shown in FIG. 2, and sucks the cleaning water in the tank 21. Discharge to a suitable place outside the machine.

The sub-tank 33 has a tank 2 at the bottom thereof.
1 and communicates with the reference water level switch 33a inside. The reference water level switch 33a detects that the water level of the wash water supplied into the tank 21 has reached the reference water level x _o , which is the height required for washing, etc., by opening the water supply valve 27. 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.

Next, an electric control device for electrically controlling the dishwasher configured as described above will be described with reference to the drawings. FIG. 2 shows a schematic circuit configuration of the device. The electric control device 40 includes a microcomputer 41, and the microcomputer 41 is a CP.
U, ROM, RAM, water supply timer, cleaning rinse timer,
It is composed of a drainage timer, I / O, etc., and a DC voltage is supplied from a power supply circuit (not shown) according to the ON state of a power switch (not shown).
Then, execution of a computer program (hereinafter referred to as a program) corresponding to the flowchart of FIG. 4 is started.

On the input side of the microcomputer 41,
The above-mentioned temperature sensor 21b is connected via the A / D converter 42, and the reference water level switch 33a is also connected. The A / D converter 42 digitally converts the detected analog signal from the temperature sensor 21b and supplies it to the I / O of the microcomputer 41.

On the output side of the microcomputer 41,
Via the drive circuits 43 to 45, the electromagnetic solenoid 27a of the water supply valve 27 and the electric motor 31 of the cleaning pump 31 described above.
a and the electric motor 32a of the drainage pump 32 are connected. The drive circuits 43 to 45 receive the output signal from the microcomputer 41 and receive the electromagnetic solenoid 27.
a, the electric motor 31a, and the electric motor 32a are driven.

Next, the operation of the embodiment configured as described above will be described. When the power switch is turned on after the rack 23 on which the dishes 24 to be cleaned are placed is accommodated in the cleaning room R, the microcomputer 41 sets the step 1 in FIG.
At 00, the execution of the program is started. After starting the execution of this program, the microcomputer 41 executes step 1
At 01, initial setting processing for setting various variables to initial values is executed. After the initial setting process, the microcomputer 41 performs a water supply routine process in step 102.

The microcomputer 41 starts the water supply routine shown in FIG.
At 21, the electromagnetic solenoid 27a of the water supply valve 27 is energized to open the water supply valve 27, and the water heater 28 is supplied from an external water supply source.
At the same time as supplying high-temperature clean cleaning water to the tank 21 through the cleaning chamber R via the
Start the water supply timer set in seconds. This 15
The set time of the second is a predetermined time such that the water level of the wash water does not reach the reference water level x ₀ due to the water supply into the tank 21. When a predetermined amount of cleaning water is supplied into the tank 21 and the water supply timer counts up for 15 seconds, the microcomputer shifts the program to step 124 based on the judgment of "YES" at step 123 to make the temperature sensor 21b. The temperature detection signal indicating the temperature T of the washing water in the tank detected by the above is input, and further, step 125
At, it is determined whether the detected temperature T is the set temperature of 60 ° C. or higher. At this time, the temperature sensor 21b is a tank 2 formed by protruding a part of the bottom wall 20a of the cleaning tank 20 downward.
Since it is attached to the outer wall of the first protruding portion 21a and the temperature is detected in a state where the washing water is stored in the protruding portion 21a, an accurate temperature detection result can be obtained. As a result, it is appropriately determined whether to drain water for 10 seconds, which will be described later.

When the detected temperature T is lower than the preset temperature of 60 ° C., the microcomputer 41 executes the drainage routine in step 126 based on the judgment of "NO" in step 125 to perform cleaning for 10 seconds or less. Drain water out of the machine. During this drainage operation, the supply of wash water is continued via the water supply valve 27, and the wash water having a set temperature of 60 ° C. or higher is stored in the tank 21 by draining for 10 seconds. Then, when the wash water reaches a predetermined reference water level x ₀ required for washing or the like, an ON signal is issued from the reference water level switch 33a, and the microcomputer 41 receives this signal and makes a determination of “YES” in step 127. At step 128, the power supply to the water supply valve 27 is stopped by stopping the power supply to the electromagnetic solenoid 27a.
Is closed, and the execution of the water supply routine is ended in step 129. On the other hand, the temperature sensor 2 in step 124
When the detected temperature T of the wash water by 1b is equal to or higher than the set temperature of 60 ° C., the microcomputer 41 shifts the program to step 127 without executing the drain routine based on the determination of “YES” in step 125, Perform the following steps as described above.

As described above, in the above water supply routine, the temperature T of the wash water is detected after the water supply is started and before the water level of the wash water reaches the reference water level x _0. Since the water is drained for a second, the discharge amount of the wash water can be suppressed to a low level and the waste of the wash water can be prevented. Further, by reducing the discharge of the wash water, the energy for heating the wash water in the water heater 28 can be efficiently used, and the wash water at a temperature of 60 ° C. or higher and not unnecessarily high can be obtained. It can be stored in the tank 21. In the water supply routine, since the drainage pump 32 drains the wash water stored in the tank 21, the drainage pump 32 does not run idle and therefore the pump is not damaged.

Thus, the set temperature in the tank 21 is 60 ° C.
When the above washing water is stored up to the reference water level x ₀ , the microcomputer 41 executes the washing routine in step 103. The microcomputer 41 starts counting the time of the cleaning and rinsing timer set to 2 minutes and starts energizing the electric motor 31a. Electric motor 31a
When the rotation of the cleaning pump 31 starts, the cleaning pump 31 sucks the cleaning water containing the detergent in the tank 21 through the supply pipe Q ₁ and pumps it to the upper and lower cleaning nozzles 25 and 26 through the supply pipes Q ₃ and Q _4. The washing of the dishes is started by the washing water sprayed from the washing nozzles 25 and 26. At this time, the temperature of the washing water is an appropriate temperature of 60 ° C. or higher, so that the dishes are effectively washed. After the lapse of 2 minutes, when the cleaning rinse timer counts up, the microcomputer 41 stops energizing the electric motor 31a and ends the cleaning routine.

Next, the microcomputer 41 executes a drainage routine process at step 104. The microcomputer 41 starts measuring the time of the drainage timer set to 30 seconds and starts energizing the electric motor 32a. When the electric motor 32a starts rotating, the drainage pump 32 discharges the dirty cleaning water in the tank 21 to appropriate places outside the machine through the supply pipes Q ₁ and Q ₅ . When the drain timer counts up after 30 seconds, the microcomputer 4
1 stops the energization of the electric motor 32a and ends the drainage routine.

Next, the microcomputer 41 executes the water supply routine shown in FIG. 4 in step 105 as described above to supply clean washing water having a temperature equal to or higher than the set temperature into the tank 21, and then in step 106. The rinse routine is executed for 30 seconds like the cleaning routine. At this time, since the temperature of the washing water is an appropriate temperature of 60 ° C or higher,
The dishes are rinsed effectively. After the completion of the rinsing routine, the microcomputer 41 executes a draining routine in step 107 in the same manner as in step 104 to discharge the cleaning water to a proper place outside the machine.

Further, the microcomputer 41 repeatedly executes the water supply, rinsing and draining routines executed in steps 105 to 107 in steps 108 to 110 to sufficiently perform the rinsing of dishes. Then, after the drainage routine ends in step 110, the microcomputer 41 ends the execution of the program in step 111.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional side view of a dishwasher according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of an electric control device of the dishwasher.

FIG. 3 is a flowchart of a “computer program” executed by the control circuit of FIG.

FIG. 4 is a flow chart showing the water supply routine of FIG. 3 in detail.

[Explanation of symbols]

20 ... Cleaning tank, 21 ... Tank, 21a ... Projection part, 21
b ... Temperature sensor, 24 ... Tableware, 27 ... Water supply valve, 27a
… Electromagnetic solenoid, 28… Water heater, 31… Washing pump,
31a ... Electric motor, 32 ... Drainage pump, 32a ... Electric motor, 41 ... Microcomputer, R ... Washing room, Q
_{1 to} Q ₇ ... Supply pipe.

Claims (2)

[Claims] 1. A water supply device for supplying cleaning water from an external water supply source through a water heater into a tank provided in the cleaning tank, and circulating the cleaning water in the tank into the cleaning tank. A washing device for washing or rinsing the dishes stored in, a drainage device for discharging the wash water stored in the tank, the water supply device, a water supply process by controlling the operation of the cleaning device and the drainage device, In a dishwasher equipped with an electric control device for repeatedly performing a one-cycle process including a washing rinsing process and a draining process, a temperature for detecting the temperature of the cleaning water supplied into the tank in the electric control device. The temperature detection result from the temperature sensor is input after a lapse of a predetermined time from the start of water supply by the sensor and the water supply device, and when the temperature detection result is lower than a predetermined temperature, the drainage device performs the Dishwasher, characterized in that a and discharge control device for controlling so that the washing water in the click discharging a predetermined time. 2. The dishwasher according to claim 1, wherein the tank is provided with a part of a bottom wall of the cleaning tank protruding downward, and the temperature sensor is arranged on the protruding portion. A dishwasher characterized by that.