JP2009183529A - Dish washer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dish washer which can quickly detect the generation of bubbles in a washing tank. <P>SOLUTION: The dish washer includes a washing tank, a washing nozzle which spouts out cleaning fluid in the washing tank, a washing pump which sucks the cleaning fluid in the washing tank and sends it to the washing nozzle, a water level detector which detects whether the water level in the washing tank reaches the standard level or not and a control device. The control device performs the bubble detection process after performing the first jet process in which the washing pump is operated and cleaning fluid is spouted through the washing nozzle in the washing tank. The bubble detection process includes the water level adjustment process in which the water level is adjusted to the standard level, the second jet process in which the washing pump is operated and the cleaning fluid is spouted out through the washing nozzle in the washing tank after the water level adjustment process, and the water level detection process which detects whether the water level in the washing tank becomes less than the standard level or not. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technique for detecting that bubbles are generated in a washing tank of a dishwasher.

  The dishwasher stores washing water in the washing tank, and the washing water in the washing tank is jetted toward the tableware by the washing pump to wash the dishes. Usually, a detergent that is difficult to foam (hereinafter referred to as a detergent for a washing machine) is used as a detergent for the dishwasher. However, if the user mistakenly introduces a detergent that easily foams (hereinafter referred to as a general detergent) such as a kitchen detergent, a large amount of foam is generated in the washing tub during washing. When a large amount of foam is generated in the washing tub, the foam may flow into a water channel or an air passage leading to the washing tub, and the dishwasher may malfunction. For example, when a water level chamber (space for detecting the water level) communicating with the washing tank is formed, bubbles may flow into the water level chamber and the dishwasher may malfunction.

  Patent Document 1 discloses a dishwasher that detects the generation of bubbles in a washing tank. This dishwasher performs the ejection stroke which spouts washing water in a washing tank with a washing pump in the state where washing water was stored in a washing tank to a standard water level. Here, when washing machine detergent is put in the dishwasher, the washing water adheres to the tableware in the washing tank and the wall surface of the washing tank (hereinafter referred to as tableware). The water level drops. In addition, when a general detergent is accidentally put into the dishwasher, in addition to the washing water adhering to the dishes, a large amount of foam is generated in the washing tank. Decrease greatly. In order to detect the presence or absence of generation of bubbles after the previous ejection stroke, the dishwasher supplies water to the washing tank for a certain period of time (water supply stroke). Then, after the water supply stroke, it is detected whether or not the water level in the cleaning tank has reached the reference water level. If the amount of decrease in the water level in the ejection stroke is small (that is, if a large amount of bubbles is not generated in the cleaning tank), the water level in the cleaning tank reaches the reference water level by the water supply stroke. If the amount of decrease in the water level in the ejection stroke is large (that is, if a large amount of bubbles is generated in the cleaning tank), the water level in the cleaning tank does not reach the reference water level even if the water supply stroke is executed. Therefore, whether or not a large amount of bubbles is generated in the cleaning tank can be detected based on whether or not the water level in the cleaning tank after the water supply stroke has reached the reference water level.

JP 2001-327454 A

  As described above, in the ejection stroke of the dishwasher of Patent Document 1, although there is a difference in the amount of decrease in the water level, the water level in the cleaning tank decreases regardless of the type of detergent. The amount of decrease in the water level when the detergent for the washing machine is charged varies depending on the amount of tableware stored in the cleaning tank (that is, the amount of cleaning water adhering to the tableware). In addition, there is an error in the amount of water supplied in the water supply stroke after the ejection stroke. Therefore, due to these variation factors, the water level in the cleaning tank after the water supply stroke varies. If the difference in water level drop due to the presence or absence of bubbles (ie, the difference in water level drop between using a general detergent and a washing machine detergent) is less than the amount of water level fluctuation, It cannot be detected whether or not bubbles are generated. That is, in the dishwasher of Patent Document 1, it is necessary to execute the ejection stroke for a long time (for example, 10 minutes) in order to increase the difference in the amount of decrease in the water level depending on the presence or absence of bubbles to easily determine the generation of bubbles. there were. That is, the dishwasher of Patent Document 1 has a problem that it takes a long time to detect the generation of bubbles in the washing tank.

  This invention is made | formed in view of the situation mentioned above, and it aims at providing the dishwasher which can detect generation | occurrence | production of the bubble in a washing tank in a short time.

The dishwasher of the present invention is based on a washing tank, a washing nozzle that jets washing water into the washing tank, a washing pump that sucks washing water in the washing tank and sends it to the washing nozzle, and a water level in the washing tank Water level detection means for detecting whether or not the water level has been reached, and a control device are provided. After supplying water to the cleaning tank, the control device operates a cleaning pump to execute a first ejection stroke in which cleaning water is jetted from the cleaning nozzle into the cleaning tank, and thereafter performs a bubble detection process. The bubble detection process includes a water level adjustment process, a second ejection stroke, and a water level detection process. In the water level adjustment process, the water level in the cleaning tank is adjusted to the reference water level. The second ejection stroke is executed after the water level adjustment process. In the second ejection stroke, the cleaning pump is operated to eject cleaning water from the cleaning nozzle into the cleaning tank. The water level detection process detects whether or not the water level in the cleaning tank is below the reference water level by the water level detection process after the start of the second ejection stroke.
In this dishwasher, washing water is jetted into the washing tank in the first jetting stroke before the foam detection process is executed. As a result, washing water is attached to the tableware or the like. In the foam detection process, the water level in the cleaning tank is adjusted to the reference water level in the water level adjustment process, and then the cleaning water is ejected into the cleaning tank in the second ejection process. At the start of the second ejection stroke, since the washing water ejected in the first ejection stroke adheres to the tableware and the like, even if the washing water is ejected in the second ejection stroke, the washing water adhered to the tableware and the like The amount of is almost unchanged. Therefore, when the detergent for the washing machine is put, the water level in the washing tank is kept at the reference water level without lowering in the second ejection stroke. On the other hand, when the general detergent is introduced, bubbles are generated in the cleaning tank in the second ejection stroke. For this reason, the water level in a washing tank falls and it is less than a reference water level. Therefore, it is possible to detect whether or not bubbles are generated in the cleaning tank by detecting whether the water level in the cleaning tank is lower than the reference water level in the water level detection process.
Thus, the dishwasher of this invention adjusts the water level in a washing tank to a reference | standard water level by a water level adjustment process, after making wash water adhere to tableware etc. by the 1st ejection process, and then the 2nd ejection process. Execute. Prior to the second jetting stroke, the cleaning water is jetted into the cleaning tank in the first jetting stroke, so that the cleaning water has already adhered to the tableware and the like in the cleaning tank at the start of the second jetting stroke. Therefore, even if the washing water ejected in the second ejection stroke adheres to the tableware or the like, it immediately flows down. Therefore, in the second ejection stroke, the water level does not decrease due to the washing water adhering to the tableware or the like. That is, it is possible to eliminate the cause of variation in the water level in the cleaning tank due to the amount of tableware stored in the cleaning tank (that is, the amount of cleaning water adhering to the tableware). Moreover, in the 2nd ejection stroke, when the detergent for washing machines is thrown in, the water level in a washing tank does not fall. Therefore, it is not necessary to supply water after the second ejection stroke. That is, it is possible to detect whether or not bubbles are generated in the cleaning tank by detecting whether or not the water level in the cleaning tank has reached the reference water level after the start of the second ejection stroke. Therefore, it is possible to eliminate the cause of water level variation due to an error in the amount of water supply. In this way, the water level variation factor due to the amount of tableware in the washing tank and the water level variation factor due to the error in the amount of water supply can be eliminated, so that the water level variation after the second ejection stroke is reduced. Therefore, it is possible to accurately detect the generation of bubbles even when the difference in water level between the case where the detergent for the washing machine is introduced and the case where the general detergent is introduced is small after the second ejection stroke. it can. That is, it is not necessary to perform the second ejection stroke for a long time. Moreover, since it is sufficient that the first ejection stroke is performed by attaching cleaning water to tableware or the like, it is not necessary to perform the first ejection stroke for a long time. Therefore, according to this dishwasher, generation | occurrence | production of the bubble in a washing tank can be detected in a short time.

In the dishwasher described above, it is preferable that the control device repeatedly executes the foam detection process and calculates the foam determination index value based on the detection result of each water level detection process.
Thus, by calculating the bubble determination index value based on the detection results of the plurality of water level detection processes, it is possible to more accurately detect whether or not bubbles are generated in the cleaning tank from the bubble determination index value. Is possible. The bubble determination index value can be calculated by various methods. For example, the number of water level detection processes detected as being below the reference water level can be used as the bubble determination index value. In this case, the higher the bubble determination index value, the higher the possibility that bubbles are generated in the cleaning tank.

When a general detergent is put into the dishwasher, the amount of new bubbles generated increases as more bubbles are present in the washing tank. That is, at the beginning of the first ejection step, bubbles are generated by the washing water ejected from the washing nozzle colliding with the wall surface and the water surface in the washing tank. If the operation is continued as it is, bubbles increase in the cleaning tank and the bubbles are caught in the cleaning pump. Accordingly, bubbles are generated even in the cleaning pump, and the amount of bubbles generated per unit time (hereinafter referred to as bubble generation speed) increases. In the dishwasher that repeatedly executes the above-described foam detection process, when a general detergent is put, more bubbles are present in the cleaning tank as the second ejection stroke is performed later. Therefore, the bubble generation speed increases as the second ejection stroke is executed later. That is, the lowering speed of the water level becomes faster as the second ejection stroke is executed later.
Therefore, it is preferable that the dishwasher which repeatedly performs the foam detection process described above shortens the execution time as the second ejection stroke is performed later by the control device.
In the second ejection stroke to be executed later, the water level is lowered at a high speed when the general detergent is added, so that the water level is sufficiently lowered even if the execution time is short. Therefore, even if the execution time of the second ejection stroke is short, it can be detected whether or not bubbles are generated in the cleaning tank. Moreover, according to such a structure, generation | occurrence | production of a bubble can be detected in a shorter time.

  According to the dishwasher of this invention, generation | occurrence | production of the bubble in a washing tank is detectable in a short time.

(Example)
An embodiment of the dishwasher of the present invention will be described with reference to the drawings. FIG. 1: has shown schematic sectional drawing of the dishwasher 10 of a present Example.
The dishwasher 10 includes a case 12 and a cleaning tank 14 accommodated in the case 12. A door 15 is integrally attached to the front side of the cleaning tank 14 (left side in FIG. 1). By pulling out the door 15, the cleaning tank 14 is pulled out from the case 12, and the tableware can be placed in the cleaning tank 14. As shown in the drawing, in the state where the cleaning tank 14 is housed in the case 12, the upper part of the cleaning tank 14 is closed by the lid 56.

  An operation panel 16 is provided on the upper portion of the door 15. A control device 60 is installed near the operation panel 16. The control device 60 controls the operation of each part of the dishwasher 10.

  The door 15 has an exhaust passage 18 that communicates the front surface of the door 15 and the cleaning tank 14. An exhaust damper 19 is installed in the middle of the exhaust passage 18.

  The door 15 is provided with a detergent storage tank 62. Detergent is stored in the detergent storage tank 62. The detergent storage tank 62 is provided with an inlet (not shown) for replenishing detergent from the front surface of the door 15. The detergent is replenished to the detergent storage tank 62 by the user. The detergent storage tank 62 communicates with the cleaning tank 14 by a detergent supply path 64. A detergent supply valve 66 is installed in the middle of the detergent supply path 64. When the detergent supply valve 66 is opened, the detergent in the detergent storage tank 62 is supplied into the cleaning tank 14 through the detergent supply path 64. The detergent supply valve 66 is controlled by the control device 60.

A dish basket 61 and a cleaning nozzle 22 are installed in the cleaning tank 14.
Tableware can be placed in the tableware basket 61.
The cleaning nozzle 22 ejects cleaning water supplied from an impeller housing chamber 31 to be described later into the cleaning tank 14 from a plurality of ejection ports. As a result, washing water is applied to the tableware placed in the tableware basket 61, and the tableware is washed.
A recess 29 is formed on the bottom surface of the cleaning tank 14. The upper opening of the recess 29 is covered with the leftover filter 17. The leftover filter 17 is formed in a mesh shape.

A water level chamber 45 is installed between the cleaning tank 14 and the door 15. The water level chamber 45 communicates with the cleaning tank 14 through the communication passage 50. One end of the communication path 50 opens at the bottom of the cleaning tank 14 (the wall surface of the recess 29), and the other end opens at the bottom of the water level chamber 45. The upper part of the water level chamber 45 is open to the atmosphere at a position not shown. Therefore, when the cleaning water is stored in the cleaning tank 14, the cleaning water is stored in the water level chamber 45 up to substantially the same water level as the cleaning tank 14.
In the water level chamber 45, a water level detection device 46 for detecting the water level in the water level chamber 45 is installed. The water level detection device 46 includes a float 47, a shaft 48, and a water level detection switch 49 (for example, a reed switch). The shaft 48 is inserted into a hole formed in the upper portion of the water level chamber 45 and is slidable up and down. The float 47 is fixed to the lower end of the shaft 48. The float 47 floats in the water. Accordingly, when the cleaning water accumulates in the water level chamber 45, the float 47 and the shaft 48 move up and down according to the level of the cleaning water. The water level detection switch 49 is installed at a position facing the upper end of the shaft 48. When the water level in the water level chamber 45 rises to a certain level, the shaft 48 contacts the water level detection switch 49. As a result, the water level detection switch 49 is turned on. That is, the water level detection device 46 is turned on. Hereinafter, the water level at which the water level detection device 46 is turned on is referred to as a reference water level. The on / off state of the water level detection device 46 is read by the control device 60.

  One end of a water supply pipe 43 is connected to the back surface of the cleaning tank 14. The other end of the water supply pipe 43 is drawn out of the case 12 and is connected to the water supply source 40. A water supply valve 44 is provided in the middle of the water supply pipe 43. When the water supply valve 44 is opened, tap water is introduced into the cleaning tank 14. The water supply valve 44 is controlled by the control device 60.

  A water channel 32 is formed below the cleaning tank 14. One end of the water channel 32 opens to the wall surface of the recess 29, and the other end opens to the impeller accommodating chamber 31. An impeller 27 for the cleaning pump 28 is installed in the impeller accommodating chamber 31. A cleaning nozzle 22 is connected to the upper portion of the impeller accommodating chamber 31. A drain pipe 36 is connected to the lower part of the impeller accommodating chamber 31. The cleaning pump 28 rotates the impeller 27 by a built-in electric motor. The cleaning pump 28 can rotate the impeller 27 in one direction or in the reverse direction. When the cleaning pump 28 rotates the impeller 27 in the one direction, cleaning water is sent from the water channel 32 to the cleaning nozzle 22, and when the cleaning pump 28 rotates the impeller 27 in the reverse direction, the water channel 32 passes to the drain pipe 36. Wash water is sent in (functions as a drain pump when rotating in the reverse direction). The cleaning pump 28 is controlled by the control device 60.

  One end of the drain pipe 36 is connected to the lower portion of the impeller accommodating chamber 31, and the other end is drawn out of the case 12 and connected to the drain section 34. When the cleaning pump 28 rotates the impeller 27 in the reverse direction, the cleaning water in the cleaning tank 14 is discharged to the drainage part 34 through the water channel 32 and the drain pipe 36.

  One end of an air vent pipe 37 is opened on the back surface of the cleaning tank 14. The other end of the air vent pipe 37 is connected to the middle of the drain pipe 36. The air vent pipe 37 prevents the water in the cleaning tank 14 from being discharged from the drain pipe 36 by using the drain pipe 36 as a siphon.

An air supply pipe 54 is connected to the back surface of the cleaning tank 14. A fan 52 is installed at the other end of the air supply pipe 54. When the fan 52 is operated, air is sent from the air supply pipe 54 into the cleaning tank 14.
A heater 30 is installed below the connection portion of the air supply pipe 54 in the cleaning tank 14. When the heater 30 is operated while the cleaning water is accumulated in the cleaning tank 14, the cleaning water is heated. When the heater 30 is operated in a state where no cleaning water is accumulated in the cleaning tank 14, the air in the cleaning tank 14 is heated.

  Next, the process which detects the foam which the dishwasher 10 performs at the time of the start of a washing | cleaning process is demonstrated. FIG. 2 is a flowchart showing processing executed by the control device 60. The control device 60 counts a count value C1 indicating the possibility that bubbles are generated in the cleaning tank 14 while advancing each step of the flowchart of FIG. And generation | occurrence | production of the bubble in the washing tank 14 is detected based on count value C1.

  In step S <b> 2, the control device 60 discharges the washing water remaining in the dishwasher 10. That is, the control device 60 rotates the impeller 27 of the cleaning pump 28 in the reverse direction. If cleaning water from the previous use remains in the recess 29 or the drain pipe 36, the remaining cleaning water is discharged in step S2. When the cleaning pump 28 is operated for a predetermined time, the control device 60 stops the cleaning pump 28.

In step S4, cleaning water and detergent are supplied into the cleaning tank. That is, the control device 60 opens the water supply valve 44 and opens the detergent supply valve 66. When the water supply valve 44 is opened, tap water (that is, cleaning water) is introduced into the cleaning tank 14 from the water supply pipe 43. When the detergent supply valve 66 is opened, the detergent is supplied from the detergent storage tank 62 into the cleaning tank 14. Therefore, water in which the cleaning water and the detergent are mixed (hereinafter simply referred to as cleaning water) accumulates in the cleaning tank 14. Further, since the water level chamber 45 communicates with the cleaning tank 14, when cleaning water accumulates in the cleaning tank 14, the cleaning water also accumulates in the water level chamber 45 to the same water level as the cleaning tank 14. In step S4, cleaning water is stored in the cleaning tank 14 until the water level detection device 46 is turned on. When the water level detection device 46 is turned on, the control device 60 closes the water supply valve 44 and the detergent supply valve 66. Therefore, at the end of step S4, the cleaning water is in the cleaning tank 14 up to the reference water level.
If the user accidentally replenishes the detergent storage tank 62 with the general detergent, the general detergent is put into the cleaning tank 14 in step S4.

In step S6, the control device 60 operates the cleaning pump 28 (rotates the impeller 27 in the one direction). At the same time, the heater 30 is operated. When the cleaning pump 28 and the heater 30 are operated, the cleaning water accumulated in the cleaning tank 14 flows into the water channel 32 and is sent from the cleaning pump 28 to the cleaning nozzle 22. The washing water sent to the washing nozzle 22 is ejected from the jet nozzle of the washing nozzle 22 into the washing tank 14. This cleans the dishes. Step S6 is executed for about 30 seconds.
During the execution of step S6, the water level in the cleaning tank 14 decreases. When the washing machine detergent is put in the washing tank 14, the water level in the washing tank 14 is lowered by the sprayed washing water adhering to the tableware or the like. The water level after execution of step S6 varies depending on the conditions during execution of step S6. For example, when a relatively large amount of cleaning water is stored in the cleaning tank 14 at the start of step S6 due to an error in the amount of water supplied in step S4 (that is, cleaning water is stored up to a level slightly higher than the reference water level). ), The water level after step S6 is relatively high. When a relatively large amount of tableware is stored in the cleaning tank 14, the amount of cleaning water attached to the tableware increases in step S6, so that the water level after execution of step S6 is relatively low. Therefore, when the detergent for washing machine is thrown in, the water level in the washing tank 14 after the execution of step S6 may be lower than the reference water level or may have reached the reference water level. In addition, when a general detergent is added, in addition to the washing water adhering to the tableware or the like, the water level is also lowered by the generation of bubbles in the washing tank 14 (that is, the washing water is foamed). Since it becomes a liquid film, the water level in the cleaning tank 14 is lowered). In this case, the amount of decrease in the water level is greater than when the detergent for the washing machine is introduced. When the general detergent is put, the water level in the cleaning tank 14 after the execution of step S6 is lower than the reference water level.

  In step S8, the control device 60 stops the cleaning pump 28. And it waits for 5 seconds in the state. The flow of the cleaning water in the cleaning tank 14 is stopped by waiting for 5 seconds. The heater 30 is continuously operated after step S8.

  After waiting for 5 seconds, the control device 60 detects whether or not the water level detection device 46 is turned on in step S10. As described above, since the water level in the cleaning tank 14 is lower than the reference water level when the general detergent is introduced, in step S10, it is detected that the water level detection device 46 is turned off. On the other hand, when the detergent for the washing machine is inserted, the water level in the cleaning tank 14 may or may not reach the reference water level, and therefore the water level detection device 46 is turned on or off in step S10. Is detected. Therefore, it cannot be determined from the detection result in step S10 whether or not bubbles are generated in the cleaning tank 14. However, when the water level detection device 46 is off, it can be said that bubbles may be generated in the cleaning tank 14. Therefore, the control device 60 employs the determination result of step S10 as one of indexes for determining whether or not bubbles are generated. That is, when the control device 60 detects that the water level detection device 46 is turned off in step S10 (ie, NO in step S10), the control device 60 sets the count value C1 to “1” (step S12). On the other hand, when the water level detection device 46 is on in step S10 (that is, YES in step S10), the control device 60 sets the count value C1 to “0” (step S14).

  In step S <b> 16, the control device 60 opens the water supply valve 44 and supplies water to the cleaning tank 14. Thereby, the water level in the cleaning tank 14 is adjusted to the reference water level. That is, when the water level in the cleaning tank 14 is lower than the reference water level (NO in step S10), the control device 60 supplies water to the cleaning tank 14 until the water level detection device 46 is turned on. Thus, the tableware washing machine 10 of a present Example adjusts the water level in the washing tank 14 by supplying the washing tank 14 with water. If the water level in the cleaning tank 14 has reached the reference water level (YES in step S10), no water is supplied in step S16 (that is, the state in which the reference water level has been reached is maintained).

In step S18, the control device 60 operates the cleaning pump 28 (rotates the impeller 27 in the one direction). As a result, cleaning water is ejected into the cleaning tank 14.
Since the washing water has already been ejected into the washing tank 14 in step S6, the washing water has already adhered to the tableware or the like in the state before the execution of step S18. Therefore, the cleaning water sprayed into the cleaning tank 14 in step S18 once adheres to the wall surface of the cleaning tank 14 or the tableware in the cleaning tank 14, but immediately flows down. Therefore, in step S18, the water level in the cleaning tank 14 does not decrease due to the cleaning water adhering to the tableware or the like. That is, when the detergent for the cleaning machine is put, the water level in the cleaning tank 14 hardly decreases and the water level detection device 46 does not turn off.
On the other hand, when the general detergent is put, bubbles are generated in the cleaning tank 14 due to the ejection of cleaning water into the cleaning tank 14. Accordingly, the water level in the cleaning tank 14 is lowered to a water level lower than the reference water level, and the water level detection device 46 is turned off.

  In step S20, the control device 60 stops the cleaning pump 28 and waits for 5 seconds in that state. The flow of the cleaning water in the cleaning tank 14 is stopped by waiting for 5 seconds.

In step S22, the control device 60 detects whether or not the water level detection device 46 is on. When bubbles are generated in the cleaning tank 14, the water level in the cleaning tank 14 is lower than the reference water level, and therefore the water level detection device 46 is detected to be off in step S22. On the other hand, when bubbles are not generated in the cleaning tank 14, since the water level in the cleaning tank 14 has reached the reference water level, the ON of the water level detection device 46 is detected in step S22. Therefore, it is possible to determine whether or not bubbles are generated in the cleaning tank 14 based on the detection result in step S22.
In this manner, the generation of bubbles can be detected based on the detection result in step S22. In addition, the control apparatus 60 continues the step demonstrated below in order to further improve the detection precision of bubble generation | occurrence | production.

When detecting that the water level detection device 46 is turned off in step S22 (that is, NO in step S22), the control device 60 adds “1” to the current count value C1 (step S24). Thus, the count value C1 is changed to a value indicating that there is a high possibility that bubbles are generated.
On the other hand, when it is detected that the water level detection device 46 is turned on in step S22 (that is, YES in step S22), the control device 60 does not execute step S22 (that is, the count value C1 does not increase).

  In step S26, the control device 60 determines the count value C1. The determination of the count value C1 will be described in detail later.

  As indicated by an arrow X in FIG. 2, the control device 60 repeatedly executes the processes of steps S16 to S26. By repeatedly executing the processes of steps S16 to S26, the count value C1 is changed according to the detection result of step S22 each time. That is, the higher the possibility that bubbles are generated in the cleaning tank 14, the count value C1 is changed to a larger value.

  As described above, the control device 60 determines the count value C1 in step S26. Hereinafter, the determination in step S26 will be described in detail.

  In the first step S <b> 26, the control device 60 executes the processes of steps S <b> 16 to S <b> 26 again regardless of the count value C <b> 1 (arrow X in FIG. 2).

In step S26 for the second time, the control device 60 determines whether the count value C1 is “1” or less, “2”, or “3”.
The count value C1 being “3” means that the water level detection device 46 is detected to be off in all the executed steps S10 and S22, and there is a possibility that bubbles are generated in the cleaning tank 14. Means extremely high. Therefore, when the count value C1 is “3”, the control device 60 executes the defoaming operation in step S30 (arrow Z in FIG. 2). The defoaming operation is an operation in which a discharge operation for discharging substantially all of the cleaning water in the cleaning tank 14 and a water supply operation for introducing new cleaning water into the cleaning tank 14 are repeated four times. Due to the defoaming operation, bubbles in the cleaning tank 14 disappear. When the defoaming operation is executed, the control device 60 ends the operation.
That the count value C1 is “1” or less means that there is an extremely high possibility that bubbles are not generated in the cleaning tank 14. That is, as described above, in step S10, the water level detection device 46 may be turned off even when bubbles are not generated in the cleaning tank 14. On the other hand, in step S22, if no bubbles are generated in the cleaning tank 14, the water level detection device 46 is on. Therefore, when bubbles are not generated in the cleaning tank 14, the count value C1 is “0” or “1”. When the count value C1 is “1” or less, the control device 60 executes the cleaning operation of step S28 (operation for continuously cleaning the dishes by operating the cleaning pump 28 and the heater 30) (FIG. 2 arrow Y). After performing the washing operation, a rinsing operation and a drying operation are performed.
The count value C1 being “2” means that bubbles may or may not be generated in the cleaning tank 14. For example, when the amount of bubbles generated in the cleaning tank 14 is just below the allowable range, the water level detection device 46 is turned off or not turned off in step S22, so the count value C1 becomes “2”. There is a case. Thus, when the count value C1 is “2”, the control device 60 executes the processes of steps S16 to S26 again (arrow X in FIG. 2).

  In step S26 for the third time, the control device 60 determines whether or not the count value C1 is “3”. When the count value C1 is “3”, the control device 60 executes the defoaming process in step S30 (arrow Z in FIG. 2). When the count value C1 is not “3” (that is, when the count value C1 is “2”), the control device 60 executes the processes of steps S16 to S26 again (arrow X in FIG. 2).

  In the fourth step S26, the control device 60 determines whether or not the count value C1 is “3”. When the count value C1 is “3”, the control device 60 executes the defoaming process in step S30 (arrow Z in FIG. 2). When the count value C1 is not “3” (that is, when the count value C1 is “2”), the control device 60 performs the cleaning operation in step S28 (arrow Y in FIG. 2).

  As described above, the control device 60 repeatedly executes Steps S16 to S26, and calculates the count value C1 based on each determination result of Step S22 that is repeatedly performed. Then, based on the calculated count value C1, it is determined whether or not bubbles are generated in the cleaning tank 14 (that is, whether to shift to a defoaming operation or to shift to a cleaning operation).

Further, as described above, when the general detergent is introduced, bubbles are generated in the cleaning tank 14 during the execution of step S18. Since the bubbles generated in the cleaning tank 14 do not disappear in a short time, the bubbles are accumulated in the cleaning tank 14 every time step S18 is executed. Therefore, step S18 executed later is executed with more bubbles in the cleaning tank 14 than step S18 executed earlier. If there are many bubbles in the cleaning tank 14, the bubbles are caught in the cleaning pump 28, so that bubbles are generated in the cleaning pump 28. Then, the bubble generation speed increases. That is, in step S18 executed later, the bubble generation speed becomes faster and the water level lowering speed becomes faster.
Therefore, the control device 60 shortens the execution time in step S18 to be executed later. Specifically, in the first step S18, the cleaning pump 28 is operated for 20 seconds. In the second step S18, the cleaning pump 28 is operated for 15 seconds. In the third step S18, the cleaning pump 28 is operated for 10 seconds. In the fourth step S18, the cleaning pump 28 is operated for 5 seconds. At the time of introduction of the general detergent, the water level lowering speed becomes faster in step S18 executed later, so in step S18 executed later, the water level in the cleaning tank 14 is higher than the reference water level even if the execution time is short. It drops to a low water level. Therefore, even if the execution time of step S18 is short, the determination of step S22 can be performed accurately. Further, the execution time of the entire process of FIG. 2 is shortened by shortening the execution time in step S18 performed later. Therefore, it is possible to detect the occurrence of bubbles in a short time.

  As described above, the tableware washing machine 10 of the present embodiment, after ejecting the washing water into the washing tank 14 in step S6 (that is, after the washing water is attached to the tableware or the like), in step S16. The water level in the cleaning tank 14 is adjusted to the reference water level. And after execution of step 16, wash water is jetted in the washing tank 14 again by step S18. Therefore, in step S18, the water level does not decrease due to the washing water adhering to the tableware or the like. That is, the water level in the cleaning tank 14 hardly varies depending on the amount of tableware stored in the cleaning tank 14 (that is, the amount of cleaning water adhering to the tableware). Further, since the water level is detected without performing water supply after step S18 (step S22), the water level does not vary due to an error in the water supply amount. Therefore, even if the difference in water level between the case where bubbles are generated and the case where bubbles are not generated is small, the generation of bubbles can be accurately detected. That is, the time for spraying the cleaning water into the cleaning tank 14 can be shortened. According to the tableware washing machine 10 of a present Example, generation | occurrence | production of the bubble in the washing tank 14 is detectable in a short time.

Moreover, in the dishwasher 10 of a present Example, step S16-S26 is performed repeatedly and multiple determination results of step S22 are acquired. And the count value C1 is changed according to each acquired determination result. And generation | occurrence | production of the bubble in the washing tank 14 is detected based on the count value C1 calculated in this way. Therefore, the detection accuracy of bubble generation can be improved.
The count value C1 is also changed according to the determination result in step S10. Thereby, the detection accuracy of generation | occurrence | production of a bubble is raised more.

  In addition, in the dishwasher 10 of a present Example, the detection accuracy of bubble generation | occurrence | production is improved by performing step S16-S26 repeatedly. However, the accuracy of the determination result in step S22 is quite high. Therefore, the generation of bubbles may be detected based on the determination result itself in step S22. That is, steps S2, S4, S6, S16, S18, S20, and S22 are executed, and the generation of bubbles is detected only by the determination result of step S22. In this case, if the water level detection device 46 is off in step S22, it is determined that bubbles are generated. According to such a configuration, it is possible to detect the generation of bubbles in a shorter time. In this case, since the determination in step S10 is not executed, the water level stored in step S4 may be any water level as long as the cleaning pump 28 can eject the cleaning water. That is, in step S4, the water level in the cleaning tank 14 may be higher than the reference water level or lower than the reference water level. When the water level in the cleaning tank 14 is set higher than the reference water level in step S4, it is necessary to adjust the water level in the cleaning tank 14 by discharging the cleaning water from the cleaning tank 14 in step S16.

  Moreover, in the dishwasher 10 of a present Example, after ejecting washing water at Step S18, after waiting for 5 seconds at Step S20, ON / OFF of the water level detection apparatus 46 was detected at Step S22. However, step S22 may be executed without executing step S20. Further, step S18 and step S22 may be executed in parallel (that is, whether or not the water level detection device 46 is turned off while the washing pump 18 is operated during the execution of step S18). Good). According to such a configuration, it is detected whether or not the water level in the cleaning tank 14 has reached the reference water level before the flow of the cleaning water is stopped. It is possible to detect the generation of bubbles in the cleaning tank 14 over time.

The dishwasher of the above-described embodiment has the following configuration in addition to the configuration of the claims.
(Configuration 1) The control device executes a second water level adjustment process (step S4) for adjusting the water level in the cleaning tank to the reference water level before executing the first ejection stroke (step S6).
(Configuration 2) The control device detects whether or not the water level in the cleaning tank is lower than the reference water level after the start of the first ejection stroke and before executing the bubble detection process (steps S16 to S22). Two water level detection processing (step S10) is performed. Then, the bubble determination index value is calculated based on the detection result of the second water level detection process and the detection result of the first water level detection process (step S18).

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.
The technical elements described in this specification or the 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.

1 is a schematic sectional view of the dishwasher 10. The flowchart which shows the process which detects a bubble.

Explanation of symbols

10: Dishwasher 12: Case 14: Washing tank 15: Door 16: Operation panel 18: Exhaust passage 22: Washing nozzle 27: Impeller 28: Washing pump 30: Heater 31: Impeller receiving chamber 36: Drain pipe 43: Water supply pipe 44: Water supply valve 45: Water level chamber 46: Water level detection device 52: Fan 54: Air supply pipe 56: Lid 60: Control device 62: Detergent storage tank

Claims (3)

A washing tank;
A cleaning nozzle for jetting cleaning water into the cleaning tank;
A cleaning pump that sucks the cleaning water in the cleaning tank and sends it to the cleaning nozzle;
Water level detection means for detecting whether or not the water level in the washing tank has reached the reference water level;
Equipped with a control device,
The control unit
After supplying water to the washing tank, the washing pump is operated to execute the first jetting process for jetting washing water from the washing nozzle into the washing tank.
A water level adjustment process for adjusting the water level in the washing tank to the reference water level;
After the water level adjustment processing, a second ejection stroke is performed in which the washing pump is operated to eject washing water from the washing nozzle into the washing tank;
A water level detection process for detecting whether or not the water level in the washing tank is below a reference water level by the water level detection means after the start of the second ejection stroke;
The dishwasher characterized by performing the foam detection process containing.   The dishwasher according to claim 1, wherein the control device repeatedly executes the foam detection process and calculates a foam determination index value based on a detection result of each water level detection process.   3. The dishwasher according to claim 2, wherein the control device shortens the execution time as the second ejection stroke is executed later.

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