JP2003339610A - Water level detector for dishwasher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water level detector for a dishwasher which is not affected by the foam of detergent. <P>SOLUTION: The water level detector 14 for the dishwasher is provided with: a case 25 communicating with the inside of a washing tub 2 for the dishwasher; floats 26 and 27 provided within the case 25 and moved vertically in accordance with the height of the water level of water including the foam of detergent having entered the inside of the case 25 from the inside of the washing tub 2; and a water level switch operated by the floats 26 and 27 when the water level within the case 25 reaches the height of a prescribed water level. The inside of the case 25 has a structure where the foam of detergent is less likely to flows just below the floats 26 and 27. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water level detecting device for a dishwasher.

[0002]

2. Description of the Related Art FIG. 1 is a sectional view of a dishwasher, FIG. 2 is a sectional view taken along the line AB of the water level detecting device of FIG. 1, and FIG. 3 is a block diagram showing the configuration of a control circuit. FIG. 1 will be described below. A washing tank (which also serves as a drying chamber) 2 is arranged inside the machine frame 1 of the dishwasher, and a front opening of the washing tank 2 is
The door 3 whose lower end is pivotally supported is in the front direction (arrow A in FIG. 1).
Direction). A rotatable arm 4 is provided at the center of the bottom of the cleaning tank 2, and a plurality of nozzles 5 are formed on the upper surface thereof at a predetermined angle. A water storage section 6 is provided at the bottom of the cleaning tank 2.
A connecting water channel 7 and a drain port 8 are arranged in communication with the water storage section 6. In addition, the lower part of the water storage section 6, that is, the connecting water channel 7
Between the and, a residue filter 9 for collecting the residues that have flowed down from the tableware is provided. The residue filter 9 is provided with a large number of minute holes. Below the residue filter 9, a deodorizing filter 21 is provided on a filter cover 22 having a large number of small holes 23 formed therein.

A washing / drainage pump 10 is disposed below the bottom of the washing tank 2. During washing, the pump 10 is rotated in the forward direction so that the washing water in the water storage section 6 is passed through the connecting water passage 7 to the arm 4.
Send to. At the time of drainage, the pump 10 is rotated in the reverse direction, and the wash water in the water storage section 6 is sucked in through the drainage port 8 and the drainage hose 1
It is discharged to the outside through 1. Water supplied from the outside via the water supply valve 12 is poured into the cleaning tank 2 from a water supply port 13 arranged at the rear of the cleaning tank 2. A float 2 for detecting the water level in the cleaning chamber 2 is provided behind the cleaning tank 2.
6 and 27 (FIG. 2) are arranged, and the water in the cleaning tank 2 flows into the water level detecting device 14 through a communication port (not shown), and water of a predetermined water level is accumulated. Further, at the bottom of the cleaning tank 2, a loop for making a large circle around the rotating shaft of the arm 4 to warm the cleaning water and the rinse water and to raise the temperature of the air in the cleaning tank 2 during drying is provided. A sheathed heater 15 is provided.

A blower fan 16 which is rotationally driven by a fan motor 17 is disposed at the rear of the cleaning tank 2, and when the blower fan 16 is rotated, an intake port 18 formed on the rear surface of the machine casing 1 is used. The sucked outside air is introduced into the cleaning tank 2. In addition, the moist air in the cleaning tank 2 is distributed to the outside through an exhaust port 19 provided on the upper portion of the door 3.

A detergent storage recess 20 is formed below the inner wall of the door 3. When washing the dishes with the dishwasher, the user stores the dishes in a dish basket (not shown), opens the door 3 and installs the dish basket in the washing tank 2.
Then, an appropriate amount of detergent is placed on the detergent storage recess 20.

When the user sets dishes and detergent and the door 3 is closed, the detergent falls from the detergent accommodating recess 20 into the water storage portion 6. When the user presses the Sutokey 30, the water supply for the washing operation is first performed. That is, the water supply valve 12 is opened according to an instruction from the control unit 60, and a predetermined amount of water is stored in the bottom of the cleaning chamber 2 including the water storage unit 6. As the water supply progresses, the detergent previously dropped in the water storage section 6 is dipped in the water.

When the water has accumulated up to the predetermined water level, the cleaning operation is executed. That is, the cleaning / drainage pump 10 rotates in the normal direction according to an instruction from the control unit 60. Further, the heater 15 is energized.

By the normal rotation operation of the washing / drainage pump 10, the washing water is sent to the arm 4 through the connecting water passage 7. This cleaning water vigorously spouts from the small-diameter nozzle 5. The cleaning water hits the tableware and flows down to the bottom of the cleaning tank 2, and the residue is accumulated in the residue filter 9 provided in the water storage section 6, and the deodorizing filter 21 provided under the residue filter 9 is washed with the cleaning water. Passes through. The deodorized cleaning water passes through the connecting water passage 7 and is again injected by the nozzle 5.

Next, FIG. 2 will be described. Below the case 25 of the water level detection device 14, a communication pipe 24 into which a connection hose (not shown) connected to a communication port (not shown) of the cleaning tank 2 is inserted is provided. Inside the case 25, a first float 26 that moves up and down in association with the height of the water level of the water containing the detergent bubbles that has entered from the cleaning tank 2.
And a second float 27 are provided. The first
The float 26 is for normal water level detection for cleaning, and the second
The float 27 is for detecting an abnormal water level. A first magnet 28 is provided at the tip of the first float 26,
When the water level in the case 25 reaches the cleaning water level, the first lead switch 30, which is the first water level switch provided on the upper side of the case 25, is turned on. Similarly, a second magnet 29 is provided at the tip of the second float 27, and when the water level in the case 25 becomes an abnormal water level higher than the cleaning water level, the case is A second lead switch 31 which is a second water level switch provided on the upper side of 25.
Turn on.

The power switch 70 (Fig. 3) provided on the operation panel (not shown) is turned on, the course selection key 72 (Fig. 3) is pushed, and the start key 71 (Fig. 3) is pushed to operate. When is started, water is supplied into the cleaning tank 2 from the water supply port 13 via the water supply valve 12. Then, when water enters the case 25, the lower portion 26a of the first float 26
A buoyancy occurs due to the accumulation of air inside the. When the water level in the case 25 reaches a predetermined water level for cleaning, the first
Magnet 28 turns on the first lead switch 30.
Then, the control unit 60 (FIG. 3) detects that the predetermined water level has been reached and starts the control of the cleaning operation. As the cleaning detergent, a low-foaming special detergent is used.If the user uses a low-foaming special detergent, there is no problem in detecting the water level, but the user can directly use the foaming detergent. When even a small amount is indirectly used, such as when it adheres to tableware or tableware, the water level rises in a state that bubbles are placed on the water, and the bubbles of the detergent, not the water, cause the first float 26, The second float 27 is pushed up. Since there is a space from just below the lower part 26a of the first float 26 to the bottom of the case 25, the amount of foam of the detergent that fills the space may be large, and in fact, the amount of water used during cleaning is small. The first magnet 28 even though the predetermined water level has not been reached
Turns on the first lead switch 30, and the water supply valve 12
Is turned off and the operation is started. In that case, the arm 4
There is a problem in that the amount of water discharged from the nozzle 5 becomes small, the force of water release becomes weak, and the cleaning power decreases. In addition, the space from immediately below the lower portion 27a of the second float 27 to the bottom of the case 25 is the first float 2
Since it is larger than the space from directly below the lower portion 26a of 6 to the bottom of the case 25, the amount of detergent bubbles filling the space is also larger. As a result, bubbles easily push up the second float 27, the second float 27 floats up before the first float 26, and even the predetermined water level during cleaning is reached. Even when it has not reached, the second magnet 29 may turn on the second lead switch 31 and the control unit 60 (FIG. 3) may determine that the water level is abnormal. When the control unit 60 (FIG. 3) determines that the water level is abnormal, the cleaning operation is stopped, and the cleaning / drainage pump 10 rotates in the reverse direction for draining. In addition, the second float 2
The other cause of the second lead switch 31 provided in No. 7 to operate the second lead switch 31 is that the first float 26 is abnormal or the water valve 12 is defective (water valve). 1
2 remains open). Further, as the water level switch for detecting the water level, a micro switch interlocking with the float is used in addition to the lead switch. As described above, in the conventional water level detection device 14, the foaming of the foaming detergent causes a reduction in the cleaning power and a stoppage of the operation in the middle, so that the user may feel uncomfortable or be mistaken for a malfunction. Occurrence of claims.

Referring to FIG. The control unit 60 is C
It is mainly composed of a microcomputer including a PU 61, a ROM 62, a RAM 63, etc., and a control program is stored in the ROM 62. The CPU 61 executes various calculations and processes according to this control program. The control unit 60 includes a power switch 70 provided on the operation panel,
The operation signal is input from the start key 71, the course selection key 72, etc., the door switch 73 for detecting the opening / closing of the door 3, the first lead switch 30 for detecting the water level of the cleaning tank 2 are input. And second read switch 31, cleaning chamber 2
Sensor 7 for detecting the temperature of water stored at the bottom of the
A detection signal is input from 4 or the like. The control unit 60 also controls the water supply valve 1 via the load driving unit 75.
2. The operations of the cleaning / drainage pump 10, the fan motor 17, etc. are controlled.

[0012]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a water level detecting device for a dishwasher which is not affected by the foam of the detergent even when a foaming detergent is used.

[0013]

Means for Solving the Problems and Effects of the Invention A first water level detecting device for a dishwasher according to the present invention is provided in a case that communicates with a washing tank of the dishwasher and in the case. A float that moves up and down in conjunction with the water level height of water containing detergent bubbles that has entered the case from the washing tank, and when the water level in the case reaches a predetermined water level height. In a water level detecting device for a dishwasher including a water level switch operated by the float, the case is structured so that bubbles of detergent do not easily enter beneath the float.

Therefore, the inside of the case has a structure in which bubbles of the detergent do not easily enter directly under the float, and therefore even if a foaming detergent is used, the float has a high water level of water containing no bubbles. Interlock with Therefore, even if a foaming detergent is used, the float detects the water level of water without being affected by the foam of the detergent, so that the water level can be normally detected.

A second water level detecting device for a dishwasher according to the present invention is characterized in that it is provided with a means for filling a space right under the float in the case.

Therefore, the flow in the case
Since the means for filling the space directly below the door is provided, the float is linked to the height of the water containing no foam even when a foaming detergent is used. Therefore, even if a foaming detergent is used, the float detects the water level of water without being affected by the foam of the detergent, so that the water level can be normally detected.

According to a third aspect of the present invention, there is provided a water level detecting device for a dishwasher, wherein the bottom of the case just below the float is located at the bottom of the case as compared with the bottoms of other parts of the case. The feature is that it was raised to get closer.

Therefore, since the bottom of the case just below the float is higher than that of the other part of the case so as to be closer to the float, a foaming detergent is used. Even so, the float is interlocked with the height of water containing no bubbles. Therefore, even if a foaming detergent is used, the float detects the water level of water without being affected by the foam of the detergent, so that the water level can be normally detected.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION A water level detecting device for a dishwasher according to an embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a sectional view corresponding to FIG. 3 of the first embodiment of the water level detecting device of the dishwasher, and FIG. 5 is a sectional view corresponding to FIG. 3 of the second embodiment of the water level detecting device of the dishwasher.

Regarding FIG. 4, only differences from FIG. 3 will be described. Immediately below the lower part 26a of the first float 26, the first flow is located at a position facing the lower part 26a.
The first part 32 having the same planar shape as the lower portion 26a of the boot 26 or a planar shape larger than the planar shape is provided. The first part 32 is a means for filling the space directly below the lower portion 26a of the first float 26, and even if a foaming detergent is used, the lower portion 26a of the first float 26 is also used. Makes it difficult for detergent bubbles to get in underneath.
Therefore, the first float 26 is interlocked with the water level height of only water without being affected by detergent bubbles, and when the water level in the case 25 reaches a predetermined water level for cleaning, Since the first magnet 28 provided in the first float 26 turns on the first lead switch 30, the amount of water discharged from the nozzle 5 of the arm 4 during operation is a predetermined amount, The momentum of water is also normal, and the cleaning power can be secured. Further, directly below the lower portion 27a of the second float 27, at a position facing the lower portion 27a, the same as the planar shape of the lower portion 27a of the second float 27 or a planar shape larger than the planar shape. A second component 33 having is provided. The second part 33 is a means for filling the space directly below the lower portion 27a of the second float 27, and even if a foaming detergent is used, the lower portion 27a of the second float 27 is used. Makes it difficult for detergent bubbles to get in underneath. Therefore, the second float 27 is interlocked with the water level height of only water without being affected by the foam of the detergent, and the second float 27 is provided before the first float 26. The second magnet 29 provided on the second float 27 turns on the second lead switch 31 only when the water level in the case 25 reaches an abnormal water level without floating. To do. Therefore, even if the effervescent detergent is used, the user does not feel uncomfortable, and a creme that may be mistaken for a failure does not occur. Incidentally, as another means for filling the space directly under the floats 26, 27, the case just under the lower portion 26a of the first float 26 and the lower portion 27a of the second float 27 is provided. Space 2
There is a method of bringing the bottom of No. 5 closer to the lower portions 26a and 27a than the bottoms of the other portions of the case 25. Although the embodiment of the present invention includes the abnormal water level detecting means (the second float 27 and the second lead switch 31), the present invention is applicable to a water level detecting device that does not include the abnormal water level detecting means. Can also be applied.

Regarding FIG. 5, only the differences from FIG. 4 will be described. The bottom 25a of the case 25 directly below the bottom 26a of the first float 26 and the bottom 27a of the second float 27 is replaced with the bottom 3a of the other part of the case 25.
Compared with Nos. 6, 37, and 38, the first convex portion 3 is provided on the bottom 25a of the case 25 so as to approach the bottoms 26a and 27a.
4 and the second convex portion 35 are formed. The convex portion 32
The planar shapes of 33 and 33 are the same as the planar shapes of the bottom portions 26a and 27a or are larger than the planar shape. By providing the first convex portion 34 and the second convex portion 35, even if a foaming detergent is used,
The foam of the detergent is less likely to enter the lower portion 26a of the float 26 and the lower portion 27a of the second float 27. Therefore, even if a foaming detergent is used, the first float 26 is not affected by the foam of the detergent and is linked to the height of the water level, so that the water level in the case 25 during cleaning is When the water level reaches a predetermined level, the first read switch 30 is operated, so that the amount of water discharged from the nozzle 5 of the arm 4 during operation is a predetermined amount, and the power of the water is normal. Therefore, the cleaning power can be secured. Further, even when the foaming detergent is used, the second float 27 is not affected by the foam of the detergent and is linked to the water level height of only water. The second float 27 does not float up,
Only when the water level in the case 25 reaches the abnormal water level, the second float 27 is connected to the second lead switch 31.
To operate. Therefore, even if the effervescent detergent is used, the user does not feel uncomfortable, and a creme that may be mistaken for a failure does not occur. Further, the first convex portion 34 and the second convex portion 35 are connected to the bottom 25 of the case 25.
The number of parts does not increase by integrally molding with a.

[Brief description of drawings]

1 is a cross-sectional view of a conventional dishwasher.

FIG. 2 is a sectional view taken along the line AB of FIG.

FIG. 3 is a block diagram showing a configuration of a control circuit of a conventional dishwasher.

FIG. 4 is a view corresponding to FIG. 2 of the first embodiment of the water level detection device for the dishwasher of the present invention.

FIG. 5 is a view corresponding to FIG. 2 of the second embodiment.

[Explanation of symbols]

2 cleaning tank 3 doors 4 arm 5 nozzles 6 water storage 7 connected waterways 9 Residue filter 10 Washing and drainage pump 12 Water valve 14 Water level detector 15 Seesheater 21 Deodorizing filter 22 Filter cover 24 communication pipes 25 cases 26 First Float 27 Second Float 28 First magnet 29 Second magnet 30 First lead switch 31 Second lead switch 32 First part 33 Second part 34 First convex portion 35 Second convex portion 36, 37, 38 Bottom except underneath the float

Claims (3)

[Claims] 1. A case communicating with the inside of the washing tank of a dishwasher, and the case provided in the case from the inside of the washing tank.
A float that moves up and down in conjunction with the water level of water containing detergent bubbles that has entered the case, and is operated by the float when the water level in the case reaches a predetermined water level. In a water level detection device of a dishwasher equipped with a water level switch,
A water level detecting device for a dishwasher, characterized in that the inside of the case has a structure in which bubbles of a detergent do not easily enter directly under the float. 2. A means for filling a space right under the float in the case is provided.
The water level detector for the dishwasher described in. 3. The bottom of the case directly below the float,
2. The water level detecting device for a dishwasher according to claim 1, wherein the height is raised so as to be closer to the float than the bottom of the other part of the case.