JP2010227496A - Dishwasher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dishwasher capable of fixing mist generated in a washing tub to dishes without reducing it and of drastically improving washing performance. <P>SOLUTION: The dishwasher includes a washing pump 4 to apply pressure on the washing water 3 stored in a washing tub 1, a washing nozzle 5 to spray washing water 3 pressed by the washing pump 4 to dishes 7, an atomizing device 31 to atomize the washing water 3 stored in the washing tub 1 and fix it to the dishes 7 and a controller 12 to control the turning speed of the washing pump 4 to increase and decrease the amount of washing water to be sprayed from the washing nozzle 5 repeatedly while the atomizing device 31 operates. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a dishwasher for cleaning by spraying washing water onto the tableware.

  In the conventional dishwasher, in the pretreatment process of the washing process, the detergent solution splashing means atomizes and disperses detergent-dissolved washing water higher than the detergent concentration used in the washing process, and attaches it to the dishes to swell the filth. (For example, refer to Patent Document 1).

  As another technique, a washing tank for storing tableware inside, a water jetting means disposed at the inner bottom of the washing tank and having a water jet port upward, and water stored at the bottom of the washing tank are sucked And at least one of the washing step and the rinsing step, the rotation speed of the washing pump is within a range of about 70 to 90% of the predetermined first rotation speed. There is a dishwasher that performs operation while switching between the second rotation speed (see, for example, Patent Document 2).

Japanese Patent Laying-Open No. 2005-237537 (page 5-6, FIG. 1) Japanese Patent Laying-Open No. 2004-129742 (page 11-12, FIG. 6)

  In the dishwasher described in Patent Document 1, in order to further enhance the swelling effect, the washing water pressurized by the washing pump is continuously jetted in combination with the detergent liquid scattering means. There is a problem that fog generated by the liquid scattering means is reduced.

  In the dishwasher described in Patent Document 2, when the washing pump is driven at the first rotational speed, the amount of water sprayed is large, and the entire tableware in the washing tank is likely to be splashed directly. On the other hand, when the cleaning pump is driven at the second rotational speed, the rotational speed is relatively low, so the operating sound of the cleaning pump is low, and the impact sound when water collides with the inner walls of the dishes and the cleaning tank is reduced. . Further, since the second rotational speed is maintained at 70 to 90% of the first rotational speed, the decrease in the water force is not extreme, and the cleaning rate does not significantly decrease, but the first rotational speed and the second rotational speed are not increased. At the time of switching to the speed, the change in the cleaning sound is noticeable. In particular, when switching from the second rotation speed to the first rotation speed, the cleaning sound suddenly increases, so that there is a problem that it is easy for the user to hear and is very harsh.

  In addition, in order to prevent vapor leakage from the exhaust port, a dishwasher equipped with a shutter that closes to the exhaust port at atmospheric pressure and opens by blowing air is used to clean signals that cause a sudden change in the number of rotations of the cleaning pump. When input to the pump, a change occurs in the water flow of the cleaning water sprayed from the cleaning nozzle, and a pressure change occurs in the cleaning tank. Due to this pressure change, the shutter is opened, steam and the like leak from the exhaust port, and there is a risk of condensation on the front panel and the operation unit.

  The present invention has been made in order to solve the above-described problems. Even if the amount of water jetted from the cleaning nozzle is changed, the change in the cleaning sound is small and the pressure in the cleaning tank is rapidly changed. An object of the present invention is to provide a dishwasher that suppresses and does not reduce mist generated in a washing tank.

  The dishwasher according to the present invention has a washing tank in which an object to be washed is stored, a washing pump that pressurizes washing water stored in the washing tank, and a washing water pressurized by the washing pump is sprayed onto the article to be washed. The cleaning water injection unit, the atomizing device that atomizes the cleaning water stored in the cleaning tank and attaches it to the object to be cleaned, and the amount of cleaning water ejected from the cleaning water injection unit when the atomizing device is driven And a control unit that controls the rotational speed of the cleaning pump so as to increase and decrease repeatedly.

  In the present invention, when the atomizer is driven, the rotation speed of the cleaning pump is controlled so that the amount of cleaning water sprayed from the cleaning water injection section is repeatedly increased or decreased. There is no longer any mist that has been reduced. For this reason, a mist-like detergent liquid adheres to the to-be-cleaned object in a cleaning tank, the swelling effect with respect to the stain | pollution | contamination of a to-be-cleaned object improves, and there exists an effect that a to-be-cleaned object is wash | cleaned more reliably.

It is sectional drawing which shows the dishwasher which concerns on Embodiment 1 of this invention seeing from a side. 3 is a control block diagram of the dishwasher according to Embodiment 1. FIG. 4 is a flowchart showing the operation of the control device for the dishwasher according to the first embodiment. It is sectional drawing which shows the dishwasher which concerns on Embodiment 2 of this invention seeing from the side. It is sectional drawing which shows the state of the exhaust port at the time of the dishwashing in the dishwasher of Embodiment 2. FIG. It is sectional drawing which shows the state of the exhaust port at the time of the tableware drying in the dishwasher of Embodiment 2. FIG. It is a figure which shows the correlation of the rotational speed of a washing pump and time in a pre-processing process. It is a figure which shows the correlation of the rotational speed of a washing pump and time in a washing process. It is a figure which shows the correlation of the rotational speed of a washing pump and time from a pre-processing process to the last rinse process.

Embodiment 1 FIG.
1 is a cross-sectional view showing a dishwasher according to Embodiment 1 of the present invention when viewed from the side.
In FIG. 1, a water supply valve 2 for supplying tap water is provided at the upper part of the cleaning tank 1. Below the cleaning tank 1 is disposed a cleaning pump 4 that sucks, pressurizes and supplies the cleaning water 3 stored in the cleaning tank 1 upward. A cleaning nozzle 5 (cleaning water injection unit) disposed on the bottom side of the cleaning tank 1 has a plurality of injection ports 6 and is rotatably connected to an outlet of the cleaning pump 4. When the cleaning water 3 from the cleaning pump 4 flows in, the cleaning nozzle 5 rotates while spraying the cleaning water 3 from the plurality of injection ports 5.

  Above the cleaning nozzle 5, a tableware basket 8 for placing tableware 7 such as a tea bowl or a dish to be cleaned is installed. A heater 9 for heating the cleaning water 3 stored in the cleaning tank 1 is installed on the bottom side of the cleaning tank 1. A drainage pump 10 connected to the bottom of the cleaning tank 1 is provided below the cleaning tank 1. In addition, a filter 11 that collects filth such as residue washed away by washing the tableware 7 is detachably installed at the bottom of the washing tank 1.

  A control device 12 to be described later is provided on the rear surface of the front panel 17, and an exhaust port 14 is provided on the upper portion of the front panel 17. A temperature sensor 15 provided at the bottom of the cleaning tank 1 generates a signal based on the temperature of the cleaning water heated by the heater 9 and outputs the signal to the control device 12. The water level detection switch 16 is composed of, for example, a float switch, and outputs a signal to the control device 12 when the water level of the cleaning water 3 stored in the bottom of the cleaning tank 1 reaches a predetermined height. An atomizing device 31 provided through the bottom of the cleaning tank 1 includes a piezoelectric vibrator that vibrates when a voltage is applied. The vibration (ultrasonic vibration) propagates perpendicularly to the water surface of the cleaning water 3 to raise the water surface, and the cleaning water 3 is atomized from that portion.

Next, the configuration of the electrical system of the dishwasher will be described with reference to FIG. FIG. 2 is a control block diagram of the dishwasher according to the first embodiment.
The switch input unit 21 is provided, for example, on the front panel 17 and includes various switches necessary for the operation of the machine. The display unit 22 includes, for example, a plurality of lamps (LEDs) provided according to each step of dishwashing, and a buzzer that rings when an error occurs. The display unit drive circuit 23 turns on the lamp of the display unit 22 in accordance with a signal from the control device 12. The water supply valve drive circuit 24 drives the water supply valve 2 to open the valve when the ON signal from the control device 12 is input, and closes the valve when the OFF signal is input. The cleaning pump drive circuit 25 drives the cleaning pump 4 at a constant rotational speed based on a control signal from the control device 12, or drives the cleaning pump 4 at a first rotational speed (for example, 600 rpm) and a second rotational speed. It is repeatedly rotated alternately at a rotation speed (for example, 1800 rpm).

  The drain pump drive circuit 26 operates the drain pump 10 at a constant rotational speed when the ON signal from the control device 12 is input, and stops the operation when the OFF signal is input. The atomizer drive circuit 30 applies a predetermined voltage to the atomizer 31 when the ON signal from the controller 12 is input to generate vibration, and when the OFF signal is input, the atomizer 31 is supplied from the atomizer 31. Stop the generated vibration. The blower fan drive circuit 27 operates the blower fan 13 at a constant rotational speed when the ON signal from the control device 12 is input, and stops the operation when the OFF signal is input. The heater energization circuit 28 varies the energization amount of the heater 9 based on a control signal from the control device 12.

  The control device 12 described above includes a control unit that controls the machine in a pretreatment process of the main cleaning process (processes such as cleaning and rinsing). The control device 12 sets the cleaning pump 4 to the first rotational speed (for example, 600 rpm) so that the amount of cleaning water sprayed from the cleaning nozzle 5 repeatedly increases and decreases when the atomization device 31 is driven in the pretreatment process. And a second rotation speed (for example, 1800 rpm) alternately and repeatedly. In this case, the cleaning pump drive circuit 25 is controlled such that the period of the second rotation speed is 30% or less with respect to the period of the first rotation speed. Specifically, for example, the cleaning pump 4 is rotated at 600 rpm for 55 seconds and then rotated at 1800 rpm for 15 seconds, and this is repeated.

  Further, the control device 12 is detected by the temperature sensor 15 before the first predetermined time t1 (hereinafter simply referred to as “predetermined time t1”) when the cleaning pump 4 and the atomizing device 31 are driven. When the temperature of the washed water 3 is equal to or higher than a first predetermined temperature T1 (hereinafter simply referred to as “predetermined temperature T1”), the pretreatment process is terminated after the lapse of a predetermined time t1, and the process proceeds to the next process (main cleaning process). To do. Further, when the temperature of the washing water 3 detected by the temperature sensor 15 does not reach the predetermined temperature T1 within the predetermined time t1, a second predetermined time t2 longer than the predetermined time t1 (hereinafter simply referred to as “predetermined time t2”). ), The energization of the heater 9 and the driving of the cleaning pump 4 and the atomizing device 31 are continued.

Here, operation | movement of the control apparatus in a pre-processing process is explained in full detail using FIG. FIG. 3 is a flowchart showing the operation of the control device for the dishwasher according to the first embodiment.
When the tableware basket 8 on which the dirty tableware 7 is placed is housed in the washing tub 1 of this machine and a start switch (not shown) provided on the front panel 17 of this machine is turned on, the switch input unit 21 is Then, a signal corresponding to the operation is output to the control device 12. The control device 12 starts the preprocessing step when detecting the signal. First, the lamp of the display unit 22 is turned on via the display unit driving circuit to notify that the pretreatment process has been started (S1), then the valve of the water supply valve 2 is opened through the water supply valve driving circuit 24, and the washing tank 1 is opened. Tap water is supplied to the inside (S2).

  At this time, the control device 12 determines whether or not a predetermined time has passed (S3), and if the predetermined time has not passed, the control device 12 determines whether or not the water level necessary for cleaning is detected by the water level detection switch 16. When a predetermined time has passed without detecting the water level necessary for cleaning, the valve of the water supply valve 2 is closed via the water supply valve drive circuit 24 (S18), and a buzzer on the display unit 22 indicates that an error has occurred. (S19).

  On the other hand, when the water level necessary for cleaning is detected by the water level detection switch 16 before the predetermined time elapses, the control device 12 closes the valve of the water supply valve 2 via the water supply valve drive circuit 24 and closes the cleaning tank 1. The supply of tap water to is terminated (S5). Then, the cleaning pump drive circuit 25 is controlled so that the cleaning pump 4 repeatedly rotates at 600 rpm for 55 seconds and then at 1800 rpm for 15 seconds (S6). Further, the heater 9 is energized via the heater energization circuit 28 (S7), the atomizer 31 is driven via the atomizer drive circuit 30 (S8), and the variable N is set to “0” (S9). . This variable N is “0” when the heater 9 is turned on and “1” when the heater 5 is turned off.

  By the above operation, the warmed cleaning water 3 is sucked according to the rotation speed of the cleaning pump 4 and the cleaning water 3 having a different amount of water is ejected from the cleaning nozzle 5. That is, when the rotational speed of the cleaning pump 4 is 1800 rpm, the cleaning water 3 with a large amount of water is injected to the tableware 7 side, and when the rotational speed is 600 rpm, the cleaning water 3 with a small amount of water is injected. When the amount of water is small, the washing water 3 in the washing tub 1 is stirred to dissolve the detergent by jetting whether it reaches the tableware 7. On the other hand, the water surface of the washing water 3 rises by the vibration from the atomizer 31 and scatters upward, adheres to the tableware 7 and swells the filth.

  The control device 12 determines whether or not the predetermined time t1 has elapsed after setting the variable N to “0” (S10). When the predetermined time t1 has not elapsed, it is determined whether or not the temperature of the cleaning water 3 detected by the temperature sensor 15 has become equal to or higher than the predetermined temperature T1 (S20). If the temperature of the cleaning water 3 becomes equal to or higher than the predetermined temperature T1 before the predetermined time t1 has elapsed, the energization to the heater 9 is turned off (S21), and the variable N is set to “1” (S22). Then, it is determined whether or not the predetermined time t1 has elapsed since the start of the pretreatment process (S10). When the predetermined time t1 has not elapsed, the process proceeds to S20. When the predetermined time t1 has elapsed, the variable N is set to “ It is determined whether it is “0” (S11).

  In this case, since the variable N is set to “1” in S22, the drive of the cleaning pump 4 is turned off (S14), the energization to the heater 9 is turned off (S15), and then the atomizer 31 is driven. Is turned OFF (S16). And the lamp | ramp of the lighted display part 22 is light-extinguished (S17), a pre-processing process is complete | finished, and it transfers to a washing | cleaning process.

  Further, the control device 12 determines whether or not the variable N is “0” when the predetermined time t1 has elapsed without the temperature of the cleaning water 3 becoming equal to or higher than the predetermined temperature T1 (S11). In this case, since the variable N is “0”, it is determined in S12 whether the temperature of the washing water 3 is equal to or lower than the predetermined temperature T1. When the temperature of the washing water 3 is equal to or lower than the predetermined temperature T1, it is determined whether or not the predetermined time t2 has elapsed since the start of the pretreatment process (S13), and when the predetermined time t2 has not elapsed, the process returns to S12 and described above. Repeat the operation.

  When the temperature of the cleaning water 3 exceeds the predetermined temperature T1 before the predetermined time t2 has elapsed, the pretreatment process is terminated as described above (S14 to S17), and the process proceeds to the cleaning process. Further, when the predetermined time t2 has elapsed with the temperature of the cleaning water 3 kept below the predetermined temperature T1, the pretreatment process is terminated as described above (S14 to S17), and the process proceeds to the cleaning process. In this case, since the temperature of the cleaning water 3 has not reached the predetermined temperature T1, the time of the pretreatment process (predetermined time t1) is extended and the atomizing device 31 atomizes the cleaning water 3. Thereby, the swelling with respect to the stain | pollution | contamination of the tableware 7 by atomization of the washing water 3 is performed reliably even if the optimal water temperature for washing | cleaning has not been reached.

As described above, according to the first embodiment, when the atomizing device 31 is driven, the rotational speed of the cleaning pump 4 is switched so that the amount of cleaning water sprayed from the cleaning nozzle 5 repeatedly increases and decreases, In addition, since the temperature of the cleaning water 3 is raised to the predetermined temperature T1, there is an energy saving effect, and the mist from the cleaning water 3 by the atomizer 31 is stably generated without decreasing. For this reason, a mist-like detergent liquid adheres to the tableware 7 placed in the tableware basket 8, and the swelling effect with respect to the stain | pollution | contamination of the tableware 7 improves, and there exists an effect that the tableware 7 is wash | cleaned more reliably.
In addition, since the time of the pretreatment step (predetermined time t1) is extended when the temperature of the washing water is equal to or lower than the predetermined temperature T1, there is an effect that the tableware 7 is reliably swollen with respect to dirt.

Embodiment 2. FIG.
FIG. 4 is a cross-sectional view showing the dishwasher according to the second embodiment of the present invention as viewed from the side, FIG. 5 is a cross-sectional view showing the state of the exhaust port during dishwashing in the dishwasher of the second embodiment, and FIG. These are sectional drawings which show the state of the exhaust port at the time of the tableware drying in the dishwasher of Embodiment 2. FIG. In addition, the same code | symbol is attached | subjected and demonstrated to the part similar to Embodiment 1. FIG. The control block of the dishwasher will be described with reference to FIG.

  In the figure, the dishwasher according to the second embodiment houses a washing tub 1 whose upper opening is closed by an inner lid 1a so that it can be pulled out forward. When the front panel 17 is pulled forward, the inner lid 1a moves upward to open the upper opening of the cleaning tank 1, and the cleaning tank 1 can be pulled out to the front side. The upper opening of the washing tub 1 is an opening for receiving the tableware 7 in the tableware basket 8 provided in the washing tub 1 and taking out the tableware 7 from the tableware basket 8. Further, a heater 9 for heating the cleaning water 3 is installed in the cleaning tank 1, and an atomizing device 31 for atomizing the heated cleaning water 3 is provided.

  A cleaning pump 4 is attached to the outside of the bottom of the cleaning tank 1 to suck and pressurize the cleaning water 3, send it to the cleaning nozzle 5 and inject it. A dryer 18 for drying the dishes 7 washed with the washing water 3 with warm air is provided on the side wall of the basket of the washing tank 1. Although not shown in FIG. 4, the cleaning tank 1 is supplied with water by the temperature sensor 15 that detects the temperature of the cleaning water 3 heated by the heater 9 and the water supply valve 2, as in the first embodiment. A water level detection switch 16 is provided for detecting when the tap water reaches the water level necessary for cleaning.

  The exhaust port 14 provided in the upper portion of the front panel 17 is connected to an exhaust path 14a that guides high-temperature and high-humidity air in the cleaning tank 3 to the outside. The exhaust passage 14a is provided with an exhaust shutter 14b for preventing jet water from leaking out of the washing tub 1 when washing dishes, and for releasing high-temperature and high-humidity air in the washing tub 1 from the exhaust port 14 when drying dishes. It has been. The exhaust shutter 14b closes the exhaust passage 14a due to its own weight as shown in FIG. 5 when the dishwasher is not used or when washing dishes, and when the dish is dried, as shown in FIG. The exhaust passage 14a is opened by the wind pressure generated by the air flow.

  The control device 12 provided on the back surface side of the front panel 17 controls each part of the dishwasher according to each process of a pretreatment process, a cleaning process, a plurality of rinsing processes, a final rinsing process, and a drying process, for example. When the control device 12 detects an ON operation of a start switch (not shown) of an operation unit provided on the front panel 17 through the switch input unit 21, the pre-processing process is started. First, the water supply valve 2 is opened via the water supply valve drive circuit 24 to supply tap water into the cleaning tank 1. When the water level necessary for cleaning is detected by the water supply by the water level detection switch 16, the valve of the water supply valve 2 is closed and the supply of tap water into the cleaning tank 1 is terminated. Then, the rotational speed of the cleaning pump 4 is controlled via the cleaning pump drive circuit 25, and the heater 5 is energized via the heater energization circuit 28 to heat the cleaning water 3. Further, the atomizer 31 is driven via the atomizer drive circuit 30 to atomize the heated washing water 3 and attach it to the tableware 3.

  When this control is performed, if the temperature of the cleaning water 3 detected by the temperature sensor 15 before the first predetermined time t1 elapses exceeds the first predetermined temperature T1, the first predetermined time t1 elapses. Later, the pretreatment process is terminated and the process proceeds to the cleaning process. Further, when the temperature of the cleaning water 3 detected by the temperature sensor 15 does not reach the first predetermined temperature T1 within the first predetermined time t1, the second predetermined time t2 longer than the first predetermined time t1. Until the time elapses, the energization of the heater 9 and the driving of the cleaning pump 4 and the atomizing device 31 are continued, and then the process proceeds to the cleaning process.

  In the washing process, the rotation speed of the washing pump 4 is controlled while heating the washing water 3 with the heater 9, and the washing water 3 is pressurized and sprayed from the washing nozzle 5 toward the tableware 7 in the tableware basket 8, The water will remove dirt. When the dishwashing is finished, the drainage pump 10 is driven via the drainage pump drive circuit 26, the washing water 3 in the washing tank 1 is discharged to the outside, and the process proceeds to the rinsing process.

  In the rinsing process, the water supply valve 2 is driven again, and the valve is opened to supply tap water into the cleaning tank 1. Then, similarly to the cleaning step, the rotation speed of the cleaning pump 4 is controlled, and the cleaning water 3 is pressurized and sprayed from the cleaning nozzle 5 toward the tableware 7. And when rinse of the tableware 7 is complete | finished, the drainage pump 10 is driven and the washing water 3 is discharged | emitted outside. This rinsing process is repeated a plurality of times, and then the final rinsing process is performed.

  In the final rinsing step, the rotational speed of the cleaning pump 4 is controlled while the cleaning water 3 is heated by the heater 9, the cleaning water 3 is pressurized and sprayed from the cleaning nozzle 5 toward the tableware 7. Finish. When the final rinse is completed, the drainage pump 10 is driven to discharge the washing water 3 to the outside as described above, and the process proceeds to the drying process. In the drying step, the dryer 18 is driven to dry the tableware 7 and the cleaning of the tableware 7 is completed.

Next, control of the rotational speed of the cleaning pump 4 in each step will be described with reference to FIGS.
FIG. 7 is a diagram showing the correlation between the rotation speed of the cleaning pump and time in the pretreatment process.

  When driving the cleaning pump 4 in the pretreatment step, the control device 12 first controls the cleaning pump drive circuit 25 so that it is driven at a low rotational speed that is the lower limit of the rotational speed, as shown in FIG. Next, control is performed so that the rotational speed increases from the low rotational speed in steps with the same amount of change. At this time, as the rotational speed increases stepwise from the low rotational speed, the amount of the cleaning water 3 from the cleaning nozzle 5 gradually increases, and the cleaning water 3 is applied to the tableware 7. On the other hand, the control device 12 performs control so that this state is maintained for a predetermined time t3 (drive time) when the rotation speed of the cleaning pump 4 reaches a high rotation speed that is an upper limit. In this case, the washing water 3 having a large amount of water is sprayed from the washing nozzle 5 and is evenly sprinkled on the tableware 7.

  After the predetermined time t3 has elapsed, control is performed so that the rotational speed decreases stepwise from the high rotational speed with the same amount of change as described above. When the rotational speed decreases to the low rotational speed, this state is a predetermined time t4 (driving time) longer than the time t3. Control to keep. In this case, the amount of water and the water flow of the cleaning water 3 sprayed from the cleaning nozzle 5 gradually decrease, and the cleaning water 3 overflows from the cleaning nozzle 5 for a predetermined time t4. Circulate. The control of the rotation speed of the cleaning pump 4 is repeatedly performed until the pretreatment process is completed.

Thus, since the washing water 3 having a large amount of water is intermittently ejected, the mist from the washing water 3 by the atomizer 31 is stably generated without decreasing. For this reason, a mist-like detergent liquid adheres to the tableware 7 accommodated in the tableware basket 8, the swelling effect with respect to the stain | pollution | contamination of the tableware 7 improves, and there exists an effect that the tableware 7 is wash | cleaned more reliably.
In addition, since the rotational speed of the cleaning pump 4 is increased or decreased stepwise, the water flow of the cleaning water 3 sprayed from the cleaning nozzle 5 gradually changes, and a sudden change in internal pressure in the cleaning tank 1 is caused. Can be prevented. For this reason, the exhaust shutter 14b in the exhaust passage 14a does not open due to a change in internal pressure, and the atomized cleaning water 3 does not leak from the exhaust port 14.

Next, control of the rotational speed of the cleaning pump 4 in the cleaning process will be described.
FIG. 8 is a diagram showing the correlation between the rotational speed of the cleaning pump and time in the cleaning process.

  When driving the cleaning pump 4 in the cleaning process, the control device 12 first controls the cleaning pump drive circuit 25 so as to be driven at a low rotational speed that is the lower limit of the rotational speed, as shown in FIG. Then, control is performed so that the rotational speed increases with the same amount of change stepwise from a low rotational speed. When the cleaning pump 4 is driven at a low rotational speed, the cleaning water 3 is jetted from the cleaning nozzle 5 toward the tableware 7, and the amount of the cleaning water 3 from the cleaning nozzle 5 gradually increases as the rotational speed increases stepwise. Increase and wash the dishes 7. On the other hand, the control device 12 performs control so that this state is maintained for a predetermined time t5 (drive time) when the rotation speed of the cleaning pump 4 reaches a high rotation speed that is an upper limit. In this case, the washing water 3 having a large amount of water is jetted toward the tableware 7, and the dirt attached to the tableware 7 is removed.

  After the predetermined time t5 has elapsed, control is performed so that the rotational speed decreases stepwise from the high rotational speed with the same amount of change as described above. When the rotational speed decreases to the low rotational speed, this state is substantially the same as the predetermined time t6 (driving time). ) Control to hold. In this case, the amount of water and the amount of water of the cleaning water 3 sprayed from the cleaning nozzle 5 gradually decrease, and the amount of water and water enough to wet the tableware 7 with the cleaning water 3 for a predetermined time t6 is obtained from the cleaning nozzle 5. Be injected. This is because the cleaning water 5 is jetted from the cleaning nozzle 5 for the purpose of removing the dirt of the tableware 7 by the power of the enzyme of the detergent, etc., rather than removing the dirt attached to the tableware 7 by water. The control of the rotational speed of the cleaning pump 4 is repeatedly performed until the cleaning process is completed.

  In this way, in the cleaning process, the rotational speed of the cleaning pump 4 is increased stepwise from the low rotational speed, and when the high rotational speed is reached, this state is controlled to be held for a predetermined time t5. After t5 has elapsed, the rotational speed is gradually reduced from the high rotational speed to the low rotational speed, and is maintained for a predetermined time t6. This is repeated, so when the cleaning pump 4 is rotating at the high rotational speed, When the cleaning water is ejected from the cleaning nozzle 5 to sufficiently clean the tableware 7 and the cleaning pump 4 is rotating at a low rotational speed, the operation sound of the cleaning pump 4 is small and the injection from the cleaning nozzle 5 is small. Therefore, the sound generated when hitting the inner wall of the cleaning tank 1 is reduced, and the cleaning sound can be suppressed to a low level.

Further, since the rotational speed of the cleaning pump 4 is changed stepwise, as in the pretreatment step, a sudden change in internal pressure in the cleaning tank 1 can be prevented, and the exhaust shutter 14b can be prevented from being opened. . Since the exhaust shutter 14b does not open, the steam generated from the cleaning water 3 does not leak from the exhaust port 14, and the dew condensation due to the steam does not adhere to the operation unit, the face material of the kitchen, or the like.
Next, control of the rotation speed of the cleaning pump 4 in the rinsing process and the final rinsing process will be described.
FIG. 9 is a diagram showing the correlation between the rotational speed of the cleaning pump and the time from the pretreatment process to the final rinsing process.

  When driving the cleaning pump 4 in the rinsing process, the control device 12 first controls the cleaning pump drive circuit 25 so as to be driven at a low rotational speed that is the lower limit of the rotational speed, as shown in FIG. This low rotation speed is set lower than the low rotation speed of the cleaning pump 4 in the cleaning process. Next, control is performed so that the rotational speed increases from the low rotational speed in steps with the same amount of change. Then, control is performed so that this state is maintained for a predetermined time t7 (driving time) when the rotational speed of the cleaning pump 4 reaches a high rotational speed which is the upper limit. When the cleaning pump 4 is driven at a low rotational speed, the cleaning water 3 is jetted from the cleaning nozzle 5 toward the tableware 7, and the amount of the cleaning water 3 from the cleaning nozzle 5 gradually increases as the rotational speed increases stepwise. When the rotation speed increases and the rotational speed is reached, the detergent and dirt adhering to the tableware 7 are washed away.

  After the predetermined time t7 has elapsed, control is performed so that the rotational speed decreases stepwise from the high rotational speed by the same amount of change as described above, and this state is maintained for the predetermined time t8 (driving time) when the rotational speed decreases to the low rotational speed. Control. In this case, the amount of water and the water flow of the cleaning water 3 sprayed from the cleaning nozzle 5 gradually decrease, and the detergent and dirt adhering to the tableware 7 are washed away for a predetermined time t8. Control of the rotational speed of the cleaning pump 4 in the rinsing process is repeatedly performed a plurality of times. In the rinsing process, the difference between the low rotation speed and the high rotation speed is small, and the amount of change in the rotation speed is smaller than that in the cleaning process.

  When the plurality of rinsing steps are completed, the control device 12 enters a final rinsing step for finishing dishwashing. The purpose of this process is to raise the temperature of the tableware 7 in preparation for the subsequent drying process in addition to the finishing of the dishwashing. For this reason, as shown in FIG. 9, the cleaning pump drive circuit 25 is controlled so that the rotational speed of the cleaning pump 4 is driven at a low rotational speed that is the lower limit, and then the same amount of change from the low rotational speed stepwise. To control the rotation speed. Then, control is performed so that this state is maintained for a predetermined time t9 (driving time) when the rotational speed of the cleaning pump 4 reaches a high rotational speed which is an upper limit. In this case, the washing water 3 sprayed from the washing nozzle 5 is strong and removes the dirt adhering to the tableware 7.

  When the predetermined time t9 has elapsed, the control device 12 performs control so that the rotational speed decreases stepwise from the high rotational speed with the same amount of change as described above, and when this state decreases to the low rotational speed, this state is the predetermined time t10 (driving time). ) Control to hold. During this predetermined time t <b> 10, the hot washing water 3 uniformly falls on the tableware 7 and raises the temperature of the tableware 7. The control of the rotation speed of the cleaning pump 4 is repeatedly performed until the final rinsing process is completed.

  As described above, when the cleaning pump 4 is rotating at a high rotational speed, the dishwashing is finished with sufficient water flow from the cleaning nozzle 5, and when the cleaning pump 4 is rotating at a low rotational speed, The operation sound of the cleaning pump 4 is also low, and since the injection from the cleaning nozzle 9 is small, the sound generated when hitting the inner wall of the cleaning tank 1 is also low. At this time, since the rotation speed of the cleaning pump 4 changes stepwise, the change in the cleaning sound is not noticeable and the change in the cleaning sound is hardly noticeable as in the cleaning process. Can be reduced.

  Further, only in the pretreatment process, the difference in the rotational speed of the cleaning pump 4 (difference between the low rotational speed and the high rotational speed) is the largest compared to the other processes (cleaning process, rinsing process, final rinsing process), and the cleaning nozzle 5 Since the time of the low rotational speed in which the washing water 3 is not jetted is long, the average power consumption can be reduced compared with other processes, resulting in energy saving.

  When the DC motor is used for the washing pump 4 in the dishwasher according to the first and second embodiments, the rotational speed can be changed simply by changing the input voltage to the washing pump 4. Further, when the rotational speed of the cleaning pump 4 is gradually switched, it can be realized by a simple control of changing the input voltage every certain time.

  DESCRIPTION OF SYMBOLS 1 Washing tank, 1a Inner lid, 2 Water supply valve, 4 Washing pump, 5 Washing nozzle, 8 Tableware basket, 9 Heater, 10 Drain pump, 12 Control device, 13 Blower, 14 Exhaust port, 14a Exhaust path, 14b Exhaust shutter , 15 Temperature sensor, 16 Water level detection switch, 18 Dryer, 31 Atomizer.

Claims (10)

A cleaning tank in which an object to be cleaned is stored;
A cleaning pump for pressurizing the cleaning water stored in the cleaning tank;
A washing water jetting unit for jetting the washing water pressurized by the washing pump onto an object to be cleaned;
An atomizing device for atomizing the cleaning water stored in the cleaning tank and attaching it to an object to be cleaned;
A dishwasher comprising: a control unit that controls a rotation speed of the washing pump so that the amount of washing water ejected from the washing water ejection unit repeatedly increases and decreases when the atomizing device is driven. Machine.   The control unit alternately and repeatedly rotates the cleaning pump at a first rotation speed and a second rotation speed higher than the first rotation speed, and the second rotation speed for a period of the first rotation speed. 2. The dishwasher according to claim 1, wherein the period is set to 30% or less.   The controller, when driving the cleaning pump in each of the pretreatment process for driving the atomizing device, the subsequent cleaning process, the rinsing process, and the final rinsing process, is cleaned from the cleaning water injection unit. The dishwasher according to claim 1, wherein the rotational speed of the washing pump is changed stepwise so that the amount of water repeatedly increases and decreases.   4. The dishwasher according to claim 3, wherein the control unit controls a lower limit and an upper limit of a rotation speed of the washing pump and a change amount of the rotation speed that is changed stepwise in accordance with each step.   5. The dishwasher according to claim 4, wherein a lower limit and an upper limit drive time of the rotation speed of the washing pump are set in accordance with each step.   6. The dishwasher according to claim 5, wherein a driving time which is a lower limit of a rotation speed of the washing pump in the pretreatment step among the steps is set to be longest.   The dishwasher according to any one of claims 4 to 6, wherein the amount of change in the rotational speed of the washing pump is set to be the largest in the pretreatment step. A heater for heating cleaning water stored in the cleaning tank;
A temperature sensor for detecting the temperature of the wash water heated by the heater,
When the temperature of the cleaning water detected by the temperature sensor becomes equal to or higher than the first predetermined temperature before the first predetermined time elapses while the atomizer is driven, the controller The dishwasher according to any one of claims 1 to 7, characterized in that after the first predetermined time has elapsed, the drive of the washing pump and the atomizing device is stopped and the process proceeds to the next step. .   When the temperature of the washing water detected by the temperature sensor does not reach the first predetermined temperature within the first predetermined time, the control unit performs a second predetermined time longer than the first predetermined time. The dishwasher according to claim 8, wherein energization of the heater and driving of the washing pump and the atomizing device are continued until a predetermined temperature is reached within a range in which elapses.   The dishwasher according to any one of claims 1 to 9, wherein a DC motor is used for the washing pump.

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