JP4481215B2 - Dishwasher - Google Patents

Description

  The present invention relates to a dishwasher that performs water supply by opening a water supply valve as necessary. Specifically, the present invention relates to a technique for determining the type of abnormality that has occurred when an abnormality has occurred in a water supply valve.

A normal dishwasher is provided with a water level detecting means for detecting the water level in the washing tank. Many of the water level detection means use a float switch. The water level detection means is often used to detect the occurrence of water supply abnormality in addition to being used when supplying a required amount of cleaning water into the cleaning tank.
Among the water supply abnormalities, if the water supply is normal, the cause of the abnormality that is supplied when water is not supplied is a failure of the water supply valve that is not closed when the water supply valve should be closed (denoted to be closed). The poor closing of the water supply valve needs to be detected with high accuracy because it may lead to a water leak accident if left untreated. For example, in the tableware washing machine of patent document 1, the overflow switch which detects that the high water level which cannot be reached when the water supply valve is functioning normally was provided in the water level detection room provided with the float. If the overflow switch is turned on, it can be determined that a water supply valve closing failure has occurred for some reason.

  The poor closing of the water supply valve occurs when a foreign object bites into the water supply valve or the drive circuit of the water supply valve breaks down. In the dishwasher of Patent Document 1, when the overflow switch is turned on, the water supply valve is opened and the drainage pump is driven. If foreign matter is caught in the water supply valve, it can be expected that water will pass through the opened water supply valve, so that the foreign matter that has been caught will be washed away with water and the water supply abnormality will be resolved. Even if this operation is executed, if the water supply valve closing failure is not resolved, it is determined that the drive circuit of the water supply valve is faulty, and the occurrence of an abnormality is notified by sounding the buzzer or turning on the lamp.

JP 2000-18429 A

In the dishwasher of Patent Document 1, if the abnormality is not solved even if an operation for eliminating the abnormality in which the foreign matter is caught in the water supply valve is performed, it is determined that the drive circuit of the water supply valve is faulty. If the abnormality eliminating operation is not executed, it cannot be determined whether the abnormality is a foreign matter bite or a drive circuit failure. Depending on which one is the cause, the optimal countermeasure varies. If there is an abnormality with foreign matter bitten, the abnormality is often resolved by opening and closing the water supply valve several times. However, if the drive circuit is faulty, it is necessary to promptly ask a repairer to repair it. is there. In order to execute the abnormality-resolving operation without distinguishing between them, it is possible to repeatedly operate a drive circuit in which a failure has occurred.
In addition, the water supply abnormality includes not only an abnormality that is supplied when water is not supplied if normal, but also an abnormality that is not supplied when water is supplied if normal, and an abnormality that the water supply speed is extremely slow. The foreign matter removal filter installed upstream of the water supply valve may be clogged, or the water supply valve that is not open when the water supply valve should be open may be defective (open failure) There are things to do. The poor opening of the water supply valve is caused by a failure of the water supply valve drive circuit. Although there are no serious accidents such as water leaks due to abnormalities in which water is not supplied or abnormally slow in water supply speed, the dishwasher cannot be operated.
As described above, there are various types of water supply abnormality, and the countermeasures are different depending on the type of water supply abnormality, and the degree of urgency of countermeasures is different. However, at present, even if it is possible to detect the occurrence of a water supply abnormality, it is not possible to determine the type of abnormality that has occurred, so it takes time to take appropriate action. An object of the present invention is to provide a dishwasher capable of accurately detecting the occurrence of a water supply abnormality and determining the type of the water supply abnormality that has occurred.

The dishwasher created in the present invention has a washing tank for storing tableware, a water supply valve for controlling water supply to the washing tank by opening and closing, an instruction means for instructing opening and closing of the water supply valve, and a water level of the washing tank. A water level detecting means for detecting that the first water level and a second water level set higher than the first water level are reached, respectively, and a time from when the water supply valve is instructed to open until the first water level is detected. First time measuring means, second time measuring means for measuring the time from detection of the first water level to detection of the second water level, contents indicated by the indicating means, and time measured by the first time measuring means And an abnormality type discriminating means for discriminating the presence / absence and type of abnormality of the water supply operation based on the time measured by the second timing means, and an informing means for informing the abnormal type discriminated by the abnormal type discriminating means.

In the present specification, a failure that is not closed when the valve is to be closed is referred to as valve closing failure, and a failure that is not open when the valve is to be opened is referred to as valve opening failure.
There are various types of water supply abnormalities, and if there are abnormalities that need to be repaired immediately by a repair company, such as a poor water supply valve closure, they can be resolved by processing such as biting of foreign matter in the water supply valve. If there is an abnormality that can be repaired, there is also an abnormality that can be spared even if it needs to be repaired, such as clogging of the filter for removing foreign matter or defective opening of the water supply valve.
In this invention, the water level detection means which detects two water levels is provided. By measuring the time from the detection of the first water level to the detection of the second water level, the water supply speed can be grasped. Based on the content instructed by the instruction means for instructing opening / closing of the water supply valve and the water supply speed at that time, the type of water supply abnormality can be determined as follows.
When the open signal is output to the water supply valve, if the time required from the detection of the first water level to the detection of the second water level is within an allowable range, it can be considered that the water supply is normally performed. it can.
When the open signal is output to the water supply valve, if the time required from the detection of the first water level to the detection of the second water level exceeds the allowable range, it may be considered that a water supply abnormality has occurred. it can. At this time, although water is supplied, since the water supply speed is slow, it is predicted that the foreign matter removing filter is clogged.
When the open signal is output to the water supply valve, if the first water level is not detected between when the opening of the water supply valve is instructed and when the predetermined time is counted, the water supply valve is in a fully closed state It is determined that it is in progress and is notified.
The closing signal is output to the water supply valve except when water is supplied in the cleaning process and / or the rinsing process. In other words, either when there is no water in the washing tank or after the water supply is completed in the washing step and / or the rinsing step. When the closing signal is output to the water supply valve, it is a normal operation that the water level detection means detects the first water level if the water supply is completed in the washing process and / or the rinsing process. However, when the close signal is output to the water supply valve, the water level detection means is not connected to the first water level while the close signal is output to the water supply valve even though there is no water in the washing tank. If it is detected, there is nothing but a water supply abnormality. When the closing signal is output to the water supply valve, the time required from the detection of the first water level to the detection of the second water level is within the allowable range of the time required when the water supply valve is normally opened. If this is the case, it is predicted that the water supply valve is malfunctioning in the fully open state, so this is notified.
When the close signal is output to the water supply valve, the time required from the detection of the first water level to the detection of the second water level exceeds the allowable range of time required when the water supply valve is normally opened. Then, since the water supply speed is slow, it is predicted that a foreign substance is caught in the water supply valve and the water supply valve is not completely closed.
According to the present invention, the occurrence of water supply abnormality can be reliably detected and the type of water supply abnormality can be determined, so that it is possible to promptly take measures appropriate for the type of water supply abnormality.

In the dishwasher of this invention, it is preferable that the 2nd water level is set to the water level lower than the water level at the time of a washing | cleaning process and / or a rinsing process start.
According to this configuration, it is possible to detect that a water supply abnormality has occurred at an early stage of the water supply process.

Hereinafter, preferred embodiments of the present invention will be described.
(1) The water level detection means includes a water level chamber communicating with the cleaning tank, two floats disposed in the water level chamber so as to be movable up and down, and a lower switch disposed above the first float outside the water level chamber. And an upper switch located above the second flow outside the water level chamber and disposed higher than the lower switch.
(2) indicating means further comprises a total of at means you start counting when the opening of the water supply valve is indicated by a, not the first water level is detected until a predetermined time is counted by the counting means For example, it is determined that the water supply valve is in a fully closed state and is informed.
(3) During a test operation, a reference time (t2 in the embodiment) from when the first water level is detected to when the second water level is detected is determined.
(4) If the time measured from the detection of the first water level to the detection of the second water level is less than three times the reference time, the water supply valve is considered to be fully open.
(5) If the second water level is not detected even after three times the reference time has elapsed, it is assumed that the water supply valve is fully closed or the filter for removing foreign substances is clogged. Is notified.

Example 1
A dishwasher of a first embodiment embodying the present invention will be described with reference to the drawings.
As shown in FIG. 1, the dishwasher of a present Example is a drawer-type dishwasher. The door 15 is provided with an operation panel 16 and an exhaust port 18. The operation panel 16 is provided with various buttons and lamps. The main body 12 slidably supports the cleaning tank 14 via rollers and rails (not shown). When the door 15 is pulled forward (leftward in the figure), the cleaning tank 14 is pulled out together with the door 15. The cleaning tank 14 is formed in a box shape with an open top. Inside, a cleaning nozzle 20, a leftover filter 17, a tableware basket 61, and the like are mounted. The cleaning nozzle 20 includes a tower nozzle portion 23 composed of an upper nozzle 21 and a lower nozzle 22, and a horizontal nozzle portion 24. The cleaning nozzle 20 has a plurality of injection ports 21a, 22a, and 24a. The leftover filter 17 is formed in a mesh shape, and is provided for filtering out the leftovers washed away from the tableware 19 when the tableware 19 is washed. The leftover filter 17 can be removed from the washing tank 14, and the leftovers filtered off can be discarded. The tableware basket 61 is formed in a shape corresponding to the tableware 19 in order to hold various tableware (large plate, small plate, bowl, cup, ladder, spoon, etc.) 19.

A suction recess 31 is formed at the bottom of the cleaning tank 14. The upper opening of the suction recess 31 is covered with the leftover filter 17. A pump 27 is provided below the bottom surface 39 of the cleaning tank 14. The pump 27 rotates the impeller 28 by a built-in electric motor. The pump 27 can rotate the impeller 28 in one direction and can also rotate in the opposite direction. A portion where the impeller 28 of the pump 27 is disposed and the suction recess 31 are communicated with each other by a suction flow path 32. An electric heater 30 is mounted above the bottom surface 39 of the cleaning tank 14 and is covered with a slat-like cover.
A cleaning nozzle 20 is rotatably attached to the bottom surface 39 of the cleaning tank 14. The cleaning nozzle 20 and the first discharge port 11 of the pump 27 communicate with each other. Some of the plurality of spray ports formed in the cleaning nozzle 20 cause the cleaning nozzle 20 to generate a rotation moment when water is sprayed.

A drain hose 34 is connected to the rear wall 33 of the main body 12. The drain hose 34 and the second discharge port 35 of the pump 27 are communicated with each other by a drain channel 36. The middle of the drainage flow path 36 and the inside of the cleaning tank 14 are communicated by an air vent path 37. A drainage check valve 38 is mounted in the vicinity of the portion of the drainage channel 36 connected to the drainage hose 34. The drainage check valve 38 prevents drainage from flowing backward from the drainage hose 34 to the drainage flow path 36.
A water supply hose 40 is connected to the horizontal portion of the rear wall 33 of the main body 12. The other end of the water supply hose 40 is connected to the water supply pipe 88. The water supply hose 40 and the water supply pipe 88 are connected via a packing with a foreign matter removing filter 86. The water supply hose 40 may be directly supplied with tap water (cold water) or may be supplied with hot water heated by a water heater.
A water supply valve 41 is attached to the inside of the rear wall 33. The water supply valve 41 is driven by a built-in solenoid to open and close. The inlet 44 of the water supply valve 41 and the water supply hose 40 are communicated with each other by a first water supply channel 42. The outlet 64 of the water supply valve 41 and the inside of the cleaning tank 14 are communicated with each other by the second water supply channel 43.

A first water level detector 45 is provided at a lower portion outside the front portion of the cleaning tank 14. The first water level detector 45 has a water level chamber 46, a float 47, a bar 48, and a switch 49. The water level chamber 46 communicates with the suction recess 31 by a water level path 50. The float 47 is disposed in the water level chamber 46. The bar 48 is fixed to the upper part of the float 47 and protrudes upward from the water level chamber 46. The switch 49 is disposed above the bar 48.
A second water level detector 70 is provided adjacent to the first water level detector 45. As shown in FIG. 2, the second water level detector 70 includes a water level chamber 72, a first float 74, a first bar 76, a lower switch 78, a second float 80, a second bar 82, and an upper switch 84. Yes. The water level chamber 72 is also communicated with the suction recess 31 by the water level path 50. The first float 74 and the second float 80 are members having the same shape, and both are disposed in the water level chamber 72. The first bar 76 and the second bar 82 are members having the same shape, and are fixed to the upper portions of the first float 74 and the second float 80, respectively, and project upward from the water level chamber 72. The lower switch 78 and the upper switch 84 are disposed above the first bar 76 and the second bar 82, respectively. The upper switch 84 is disposed at a position 10 mm higher than the lower switch 78. The second water level detector 70 will be described in detail later.

A drying fan 52 is attached to the outside of the rear wall 51 of the cleaning tank 14. The drying fan 52 rotates the fan 53 with a built-in motor. The drying fan 52 and the cleaning tank 14 are communicated with each other through a drying path 63. The drying fan 52 is higher than the water level 54 when the cleaning water is normally supplied to the cleaning tank 14 (hereinafter referred to as “normal water level”, and the state where water is supplied up to this water level is sometimes referred to as “full water”). Highly arranged. Therefore, water can be prevented from entering the drying fan 52.
A thermistor 55 is mounted on the bottom surface 39 of the cleaning tank 14. The thermistor 55 detects the temperature of the water when the cleaning water and the rinsing water are put in the cleaning tank 14, and detects the air temperature when the cleaning water and the rinsing water are not put.
A recess 58 is formed in the bottom surface 57 of the main body 12. Two electrodes of the water leak detection sensor 59 are inserted into the recess 58. When water leaks from the cleaning tank 14 to the outside and the leaked water flows into the recess 58, the electrodes are connected and the water leak detection sensor 59 is turned on.

A controller 60 is mounted in the door 15. The controller 60 includes a CPU, a ROM, a RAM, and the like, and controls the operation of the dishwasher. The controller 60 is connected to the operation panel 16, the pump 27, the heater 30, the water supply valve 41, the first water level detector 45, the second water level detector 70, the drying fan 52, the thermistor 55, and the water leak detection sensor 59. .
A seal lid 56 is disposed above the cleaning tank 14. The seal lid 56 is connected to the cleaning tank 14 by a lifting mechanism (not shown). In a state where the cleaning tank 14 is accommodated in the main body 12 (the state shown in FIGS. 1 and 3), the seal lid 56 is lowered to cover the upper opening of the cleaning tank 14. When the cleaning tank 14 is pulled out from the main body 12 (when the cleaning tank 14 is in the state shown in FIG. 2), the seal lid 56 rises to open the upper opening of the cleaning tank 14.

  The tableware washing machine of a present Example operate | moves in order of a washing | cleaning process, a rinse process, and a drying process. When the user turns on the operation start button provided on the operation panel 16, the cleaning process is started. In addition, before starting a washing | cleaning process, the detergent is thrown into the predetermined site | part of the tableware basket 61 by the user. In the cleaning process, the water supply valve 41 is first opened. When the water supply valve 41 is opened, tap water is supplied to the cleaning tank 14 through the water supply hose 40, the first water supply channel 42, and the second water supply channel 43. When the water is supplied, the water level of the cleaning water in the cleaning tank 14 rises. Wash water flows through the suction recess 31 and the water level path 50 and enters the water level chamber 46 of the water detector 45. As the cleaning water level rises, the water level in the water level chamber 46 also rises. When the water level in the water level chamber rises, the float 47 rises. When the float 47 floats, the bar 48 rises with it. When the bar 48 rises and the upper end contacts the switch 49, the first water level detector 45 is turned on. When the first water level detector 45 is turned on, the water supply valve 41 is closed, whereby the water supply to the cleaning tank 14 is finished. When the first water level detector 45 is turned on and the water supply to the cleaning tank 14 is completed, the water level in the cleaning tank 14 is the normal water level 54 (full water). The first water level detector 45 functions as a full water detector. The normal water level 54 is slightly higher than the heater 30.

When the water supply valve 41 is closed, the pump 27 is cleaned and the heater 30 is turned on. Here, the cleaning operation of the pump 27 means that the impeller 28 of the pump 27 rotates in one direction, sucks cleaning water from the suction recess 31 via the suction flow path 32, and the sucked cleaning water is removed from the cleaning nozzle. This means an operation state to be fed into the 20. As described above, the middle of the drainage flow path 36 communicates with the inside of the cleaning tank 14 by the air vent path 37. For this reason, when the pump 27 is performing a cleaning operation, air enters the drainage flow path 36. Further, a part of the drainage channel 36 is formed in an inverted U shape. For this reason, the pump 27 performing the cleaning operation is prevented from sucking the wastewater through the drainage flow path 36.
The washing water sent to the washing nozzle 20 is ejected vigorously from the injection port. The cleaning nozzle 20 is rotated by a rotational moment generated by the ejection of the cleaning water while ejecting the cleaning water. The tableware 19 is washed by the washing water ejected from the ejection port. The washing water that has washed the tableware 19 is again sucked into the pump 27 from the suction recess 31. In this manner, the cleaning water sucked into the pump 27 is sprayed from the spray nozzle of the cleaning nozzle 20 and the circulation sucked into the pump 27 again is repeated. The leftovers washed away from the tableware 19 are filtered out by the leftovers filter 17.
When the heater 30 is turned on, the temperature of the cleaning water increases. The temperature of the washing water is detected by the thermistor 55. The heater 30 is ON / OFF controlled based on the temperature detected by the thermistor 55, and the washing water temperature is maintained within a predetermined range (for example, 45 to 60 ° C.).

  When a predetermined time (for example, 10 minutes) elapses after the cleaning water temperature is maintained within a predetermined range, the heater 30 is turned off and the pump 27 is drained. Here, the drainage operation of the pump 27 means that the impeller 28 of the pump 27 rotates in the other direction, so that the wash water is sucked from the suction recess 31 via the suction flow path 32, and the sucked wash water is discharged into the drainage flow. This means an operation state in which the fuel is discharged to the outside through the passage 36 and the drain hose 34. The drainage operation of the pump 27 ends when a predetermined time (for example, 40 seconds) elapses. The predetermined time is set as a time sufficient to drain all the cleaning water from the cleaning tank 14. When the drainage operation of the pump 27 is completed, air enters the drainage path 36 through the air vent path 37.

  In the rinsing process, the water supply valve 41 is opened and water is supplied to the cleaning tank 14. When water is supplied to the cleaning tank 14 and the first water level detector 45 is turned on and the water level is full, the water supply valve 41 is closed, the pump 27 is cleaned, and the heater 30 is turned on. When the pump 27 is in a cleaning operation, the rinsing water is sprayed from the spray nozzle 20 and the tableware 19 is rinsed. The heater 30 that is turned on heats the rinse water to warm water. When a predetermined time (for example, 1 minute) elapses after the cleaning operation of the pump 27 is started, the pump 27 stops. Then, the rinsing water is drained from the cleaning tank 14 by performing the drainage operation of the pump 27. The rinsing process is repeated a predetermined number of times (for example, 5 times).

  In the drying process, the drying fan 52 is operated and the heater 30 is turned on. When the drying fan 52 is operated, external air is sent into the cleaning tank 14 via the drying path 63. The sent air passes through the cleaning tank 14 and is exhausted to the outside through the exhaust port 18. When the heater 30 is turned on, the air temperature in the cleaning tank 14 increases. While the outside air is fed into the cleaning tank 14 and the temperature in the cleaning tank 14 becomes high, the temperature-controlled drying of the tableware 19 is performed. When a predetermined time (for example, 25 minutes) elapses after the temperature-controlled drying of the tableware 19 is started, the heater 30 is turned off and air drying is performed. When a predetermined time (for example, 5 minutes) elapses after the air-drying of the tableware 19 is started, the operation of the fan 52 is stopped and the drying process is ended. A buzzer sounds, the completion of all processes is notified, and the dishwasher is turned off.

  The water supply abnormality in the dishwasher is often caused by the opening / closing abnormality of the water supply valve 41. In particular, the poor closing of the water supply valve 41 needs to be detected with high accuracy since it may lead to a water leak accident if left untreated. The poor closing of the water supply valve 41 occurs when a foreign object bites into the water supply valve 41 or a drive circuit of the water supply valve 41 breaks down. If the cause of the poor closing of the water supply valve 41 is the foreign matter biting of the water supply valve 41, it is often solved by opening and closing the water supply valve 41 several times, but if the drive circuit of the water supply valve 41 is faulty, It is necessary to request repairs and repair them promptly. Moreover, in the water supply abnormality, there is also a defective opening of the water supply valve 41. The poor opening of the water supply valve 41 occurs when the drive circuit of the water supply valve 41 breaks down or the foreign matter removing filter 86 attached upstream of the water supply valve 41 is clogged. Although a serious accident such as a water leak does not occur due to the poor opening of the water supply valve 41, the dishwasher cannot be operated, and it is necessary to ask a repairer to repair it. As described above, there are various types of water supply abnormality, and the degree of urgency varies depending on the type of water supply abnormality.

In the dishwasher of the present embodiment, the second water level detector 70 is used to perform processing for determining the type of water supply abnormality. First, the second water level detector 70 will be described.
As described above, the water level chamber 72 of the second water level detector 70 is communicated with the suction recess 31 by the water level path 50. As shown in FIG. 2, when the water supply valve 41 is opened and water supply into the cleaning tank 14 is started, the water supplied into the cleaning tank 14 enters the water level chamber 72 from the suction recess 31 through the water level path 50. invade. As the water level rises, the first float 74 and the second float 80 also rise. The first float 74 and the second float 80 rise in the same way at the same height.
As shown in FIG. 3, when the water level further rises, the upper end of the first bar 76 of the first float 74 of the first float 74 and the second float 80 eventually comes into contact with the lower switch 78 and is turned on. At this time, the upper end of the second bar 82 of the second float 80 is not yet in contact with the upper switch 84 and remains off.
As shown in FIG. 4, the first float 74 has the upper end of the first bar 76 in contact with the lower switch 78, so that even if the water level further rises, the first float 74 does not rise any further. When the water level further rises, only the second float 80 rises, and eventually the upper end of the second bar 82 of the second float 80 comes into contact with the upper switch 84 and is turned on. The water level when the upper switch 84 is turned on is designed to be lower than the normal water level 54 shown in FIG. When normal water level 54 is supplied and the water level is full, if normal, both lower switch 78 and upper switch 84 are on.

  As shown in FIG. 5, in step S10, it is determined whether or not an open signal for the water supply valve 41 is output. When the open signal of the water supply valve 41 is output (YES in step S10), the process proceeds to step S12, and time measurement by a timer is started. During normal operation, the time t1 required from when the water supply is started until the lower switch 78 is turned on (state shown in FIG. 3) is measured and stored during the trial operation. However, the time required from when the water supply is started until the lower switch 78 is turned on is easily affected by the water level in the water level chamber 72 before the water supply is started. Proceeding to step S14, if the lower switch 78 is turned on when the time measured by the timer is less than 3 × t1, it is considered that at least the water supply valve 41 is opened and water is being supplied, and the process proceeds to step S16 and is performed by the timer. Timing starts. During normal operation, the time t2 required from when the lower switch 78 is turned on to when the upper switch 84 is turned on (state of FIG. 4) is measured and stored during the trial run. The time required from when the lower switch 78 is turned on to when the upper switch 84 is turned on does not depend on the water level in the water level chamber 72 before the start of water supply. In step S18, it is determined whether or not the upper switch 84 is turned on when the time measured by the timer is less than 3 × t2. If the time measured by the timer is less than 3 × t2, the water supply is considered normal and the process ends.

  If the lower switch 78 is not turned on (if it is off) when the time measured by the timer is less than 3 × t1 in step S14, it means that water is not supplied or that it takes too much time to supply water. There is a high possibility that the valve 41 is not properly opened or that the foreign matter removing filter 86 attached upstream of the water supply valve 41 is clogged. Therefore, it progresses to step S22, alert | reports that the water supply valve OFF failure or the filter clogging abnormality has generate | occur | produced, and a process is complete | finished. The notification of abnormality is performed by a display using a lamp on the operation panel 16 and a buzzer sound. Subsequent abnormality notification is performed in the same manner.

  If the upper switch 84 is not turned on (if it is off) when the time measured by the timer is less than 3 × t2 in step S18, the water supply valve 41 is open, but the water supply takes too much time, and the foreign matter There is a high possibility that the removal filter 86 is clogged and the flow rate is limited. Accordingly, the process proceeds to step S20 to notify that a filter clogging abnormality has occurred and the process ends.

If the opening signal of the water supply valve 41 is not output in step S10 (if NO), the process proceeds to step S24, and it is determined whether or not the closing signal of the water supply valve 41 is output. If the closing signal of the water supply valve 41 is not output (NO in step S24), the process returns to step S10. If the closing signal of the water supply valve 41 is output (YES in Step S24), the process proceeds to Step S26, and it is determined whether or not the lower switch 78 is turned on. If the lower switch 78 is turned on, it is considered that the normal water level 54 is being supplied into the cleaning tank 14, and the process returns to step S10. If the lower switch 78 is not turned on, it is considered that water is not supplied into the cleaning tank 14.
If it is determined that water is not being supplied into the cleaning tank 14, the process proceeds to step S28, and then it is monitored whether the lower switch 78 is turned on. If it is normal, since the water supply valve 41 is not opened and water is supplied into the cleaning tank 14 while the close signal of the water supply valve 41 is output, the lower switch 78 is not turned on. If the lower switch 78 is not turned on (if it is turned off in step S28), the water supply valve 41 is regarded as normally closed and the process returns to step S10. If the lower switch 78 is turned on in step S28 even though the closing signal of the water supply valve 41 is output, it is considered that some abnormality has occurred in the water supply valve 41 and the water supply valve 41 is opened. Proceeding to step S30, timing by a timer is started. In step S32, it is determined whether or not the upper switch 84 is turned on when the timer time is less than 3 × t2. If the upper switch 84 is turned on when the time measured by the timer is less than 3 × t2, there is a high possibility that the water supply valve 41 is fully open even though the water supply valve 41 close signal is output. . Therefore, it progresses to step S34, alert | reports that the abnormality of the ON failure of the water supply valve 41 has generate | occur | produced, and a process is complete | finished.

  If the upper switch 84 is not turned on (if it is off) when the time measured by the timer is less than 3 × t2 in step S32, there is a high possibility that the water supply valve 41 is biting foreign matter. Therefore, it progresses to step S36, alert | reports that the foreign material biting abnormality of the water supply valve 41 has generate | occur | produced, and a process is complete | finished.

  The water supply abnormality includes an abnormality in which water is supplied when the water supply is to be interrupted, an abnormality in which water is not supplied when water is to be supplied, and an abnormality in which the water supply speed is extremely slow. The cause of the abnormality that causes water supply when the water supply is to be interrupted is the poor closing of the water supply valve 41. If this is left unattended, there is a risk of water leakage. The poor closing of the water supply valve 41 occurs when a foreign object bites into the water supply valve 41 or a drive circuit of the water supply valve 41 breaks down. If the water supply valve 41 is bitten by a foreign object, it can be easily resolved by opening and closing the water supply valve 41 several times, so that the user can often cope without requesting a repair shop. However, if the drive circuit of the water supply valve 41 is faulty, it is necessary to promptly ask a repairer for repair. Further, the cause of the abnormality in not supplying water when water should be supplied and the abnormality in the water supply speed being extremely slow are clogging of the foreign matter removing filter 86 attached upstream of the water supply valve 41 and poor opening of the water supply valve 41. The poor opening of the water supply valve 41 is caused by a failure of the drive circuit of the water supply valve 41. Even if these are left unattended, serious accidents such as water leakage will not occur, but the operation of the dishwasher becomes impossible, so it is necessary to ask a repairer to repair it. As described above, there are various types of water supply abnormality, and the countermeasures are different depending on the type of water supply abnormality, and the degree of urgency of countermeasures is different.

The dishwasher of the present embodiment includes a second water level detector 70 that detects two water levels. By measuring the time from when the lower switch 78 is turned on to when the upper switch 84 is turned on, the water supply speed can be grasped. Whether the signal output to the water supply valve 41 is an open signal or a closed signal, and at that time, the time from when the lower switch 78 is turned on to when the upper switch 84 is turned on is normal. The type of water supply abnormality can be determined depending on whether the time is equal to or longer than the time t2 required when the is open.
(1) When the open signal is output to the water supply valve 41, if the time required from when the lower switch 78 is turned on until the upper switch 84 is turned on is less than 3 × t2, the water supply is normally performed. Yes.
(2) When an open signal is output to the water supply valve 41, water is supplied if the time required from turning on the lower switch 78 to turning on the upper switch 84 is 3 × t2 or more. Since the water supply speed is slow, it is predicted that the foreign matter removing filter 86 is clogged, and this is notified.
(3) If water supply is performed despite the close signal being output to the water supply valve 41, a water supply abnormality has occurred. If the time required for the upper switch 84 to be turned on after the lower switch 78 is turned on is less than 3 × t2 when the close signal is output to the water supply valve 41, the water supply valve 41 has failed in the fully opened state. It is predicted that it is present and this is notified.
(4) When the closing signal is output to the water supply valve 41, if the time required for the upper switch 84 to turn on after the lower switch 78 is turned on is 3 × t2 or more, the water supply speed is slow. It is predicted that a foreign object is caught in the water supply valve 41 and the water supply valve 41 is not completely closed, and this is notified.
(5) The time required until the lower switch 78 is turned on after the open signal is output to the water supply valve 41 is also counted. During the trial operation, the time t1 required when the water supply valve 41 is normally opened is measured and stored. If the time required for the lower switch 78 to be turned on after the open signal is output to the water supply valve 41 is 3 × t1 or more, it takes too much time to supply water, so the water supply valve 41 is in a fully closed state and fails. It is predicted that the foreign matter removing filter 86 is clogged, and this is notified. As a result, it is possible to detect and notify an abnormality in which water is not supplied even though the open signal is output to the water supply valve 41 at a relatively early stage.
According to the dishwasher of the present embodiment, the occurrence of water supply abnormality can be reliably detected and the type of water supply abnormality can be discriminated, so that a countermeasure suitable for the type of water supply abnormality can be performed promptly. Can do.

  Furthermore, in the dishwasher of the present embodiment, the water level detected by the second float 80 and the upper switch 84 is lower than the normal water level 54, so that even if a water supply abnormality occurs, water is supplied to the normal water level 54. It is possible to detect the occurrence of water supply abnormality at an earlier stage without waiting.

( Reference Example 1 )
A first reference example with reference to the dishwasher of the present invention will be described. The configuration of the dishwasher of this reference example is similar to the configuration of the dishwasher of the first embodiment. However, the dishwasher of this reference example does not have the first water level detector 45 and detects the first water level. The second water level detector 70 is different from the first embodiment in that the second water level detector 70 has a full water detection function. Therefore, here, the second water level detector 70 will be mainly described, and description of common parts will be omitted. Moreover, the same code | symbol is used about the site | part which is common in this reference example and 1st Example.
In the dishwasher of this reference example, the normal water level 54 of the washing tank 14 is detected using the second water level detector 70 used for performing the process of determining the type of water supply abnormality. It is designed so that the upper end of the second bar 82 of the second float 80 is in contact with the upper switch 84 as shown in FIG. When water is supplied into the cleaning tank 14, the second water level detector 70 can be provided with a full water detection function by controlling the water supply valve 41 to be opened until the upper switch 84 is turned on.
The processing for discriminating the type of water supply abnormality is the same as in the first embodiment, but in the second water level detector 70 of this reference example, the water levels detected by the lower switch 78 and the upper switch 84 are the first embodiment. Slightly higher than at the time of. That is, in this reference example, when any water supply abnormality occurs, the type of water supply abnormality is determined at a stage where the amount of water supply has increased compared to the first embodiment.

In the dishwasher of the present reference example, since the water level detected by the second float 80 and the upper switch 84 is the normal water level 54, the second water level detector 70 provided for detecting the type of water supply abnormality is provided. The first water level detector 45 of the first embodiment can be eliminated by using it as a water level detecting means for detecting the normal water level 54. It is possible to reduce the number of parts and reduce the size and cost of the device.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
In the embodiment, the time used for determining the water supply abnormality is set to three times the time (t1 or t2) set during the trial operation. However, the time can be appropriately changed within a range where the water supply abnormality can be appropriately determined. it can. For example, for determining water supply abnormality, a time that is 1 to 3 times the time set during the trial operation may be used, or a predetermined time set during shipping may be used.
In addition, the technical elements described in the present specification or drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The cross-sectional schematic diagram of the tableware washing machine of 1st Example. The cross-sectional schematic diagram of the 2nd water level detector of 1st Example (lower switch off, upper switch off). The cross-sectional schematic diagram of the 2nd water level detector of 1st Example (lower switch on, upper switch off). Sectional schematic diagram of the second water level detector of the first embodiment (lower switch on, upper switch on). The flowchart which shows the process which discriminate | determines the kind of water supply abnormality of 1st Example.

Explanation of symbols

12: Main body 14: Washing tank 31: Suction recess 41: Water supply valve 45: First water level detector 46: Water level chamber 47: Float 48: Bar 49: Switch 50: Water level path 70: Second water level detector 72: Water level chamber 74: first float 76: first bar 78: lower switch 80: second float 82: second bar 84: upper switch 86: foreign matter removing filter 88: water supply pipe

Claims (3)

A washing tank for storing tableware;
A water supply valve that controls water supply to the cleaning tank by opening and closing; and
Instruction means for instructing opening and closing of the water supply valve;
Water level detection means for detecting that the water level of the washing tank has reached the first water level and the second water level set higher than the first water level;
First timing means for timing the time from when the water supply valve is instructed to open until the first water level is detected;
A second timing means for timing the time from detection of the first water level to detection of the second water level;
An abnormality type determination means for determining the presence or absence and abnormality type of the water supply operation based on the content indicated by the instruction means, the time counted by the first timing means and the time counted by the second timing means ;
Abnormal kind determination means dishwasher, characterized in Tei Rukoto a informing means for informing the abnormal kind that discrimination.   2. The dishwasher according to claim 1, wherein the second water level is set to be lower than the water level at the start of the washing process and / or the rinsing process.   The abnormality type discrimination means is
(1) A procedure for determining that a poor opening of the water supply valve has occurred when the water supply valve is instructed to open and the time measured by the first time measuring means is equal to or longer than the first reference time;
(2) A procedure for determining that the water supply is normally performed when the water supply valve is instructed to open and the time measured by the second time measuring means is less than the second reference time;
(3) A procedure for determining that the foreign matter removing filter is clogged abnormally when the water supply valve is instructed to open and the time counted by the second time measuring means is equal to or longer than the second reference time; ,
(4) A procedure for determining that a fully open abnormality of the water supply valve has occurred when the water supply valve is instructed to close and the time measured by the second time measuring means is less than the second reference time;
(5) A procedure for determining that a foreign matter biting abnormality has occurred when the water supply valve is instructed to close and the time measured by the second time measuring means is equal to or longer than the second reference time;
  The dishwasher according to claim 1 or 2, further comprising:

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