CN211270603U

CN211270603U - Dish washing machine

Info

Publication number: CN211270603U
Application number: CN201922490271.0U
Authority: CN
Inventors: 李一峰; 李�浩; 余水勇
Original assignee: Bear Electrical Appliance Co Ltd; Foshan Bear Intelligent Electric Appliance Co Ltd
Current assignee: Bear Electrical Appliance Co Ltd; Foshan Bear Intelligent Electric Appliance Co Ltd
Priority date: 2019-12-30
Filing date: 2019-12-30
Publication date: 2020-08-18
Anticipated expiration: 2029-12-30

Abstract

The utility model discloses a dish washer, which comprises a machine body, a washing system, a water supply system and a drainage system; the washing system at least comprises an upper inner container and a lower inner container communicated with the upper inner container, and the lower inner container is arranged on the bottom surface of the upper inner container; the water supply system at least comprises a water tank assembly, the water tank assembly comprises a water tank with an overflow hole and a water outlet hole, and the water outlet hole is communicated with the water inlet of the lower inner container; the drainage system at least comprises a drainage pump fixed on the bottom surface of the lower inner container, and a water inlet of the drainage pump is communicated with a water outlet of the lower inner container; the dishwasher further includes an overflow anti-siphon system including an anti-siphon assembly in communication with the outlet of the drain pump, the anti-siphon assembly being in communication with the overflow aperture and the anti-siphon assembly being located below the overflow aperture. The utility model discloses the water tank produces the overflow and takes place the siphon during drainage when can preventing to add water, and overall structure is simple, the reliability is high and the assembly of being convenient for.

Description

Dish washing machine

Technical Field

The utility model belongs to the technical field of domestic appliance and specifically relates to a dish washer is related to.

Background

This section merely provides background information related to the present application so as to enable those skilled in the art to more fully and accurately understand the present application, which is not necessarily prior art.

The dish washer uses water to wash tableware, and combines the high-temperature action and the chemical action of a detergent, so that the tableware is cleaned.

Part dish washer makes things convenient for the needs that satisfy diversified use scene nowadays, lets dish washer from taking water tank or basin, and the user is using to go to the water tank and adds water, supplies water by the water tank for dish washer's inner bag and provides the washing. However, the existing dish washer has at least the following defects: firstly, when a user adds water into a water tank, excessive water adding is easily caused, so that part of water can overflow from a water adding port of the dish washing machine, and finally, water overflowing from the water tank and dropping on a desktop and the ground brings inconvenience to the user, for example, the danger of sliding and electric shock of the user is easily caused; secondly, when the dish washer drains water, the inner container has good sealing performance, so that the inner and outer air pressure difference is easy to form a siphon phenomenon, and sewage in the drainage pipeline is siphoned back into the inner container to pollute the washed tableware.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a dish washer prevents that dish washer water tank from producing the overflow and dish washer takes place waste water siphonage when the drainage when adding water.

The utility model provides a dish washing machine, which comprises a machine body, a washing system, a water supply system and a drainage system; the washing system at least comprises an upper inner container and a lower inner container communicated with the upper inner container, and the lower inner container is arranged on the bottom surface of the upper inner container; the water supply system at least comprises a water tank assembly, the water tank assembly comprises a water tank with an overflow hole and a water outlet hole, and the water outlet hole is communicated with the water inlet of the lower inner container; the drainage system at least comprises a drainage pump fixed on the bottom surface of the lower inner container, and a water inlet of the drainage pump is communicated with a water outlet of the lower inner container; the dishwasher further includes an overflow anti-siphon system including an anti-siphon assembly in communication with the outlet of the drain pump, the anti-siphon assembly being in communication with the overflow aperture and the anti-siphon assembly being located below the overflow aperture.

Preferably, the upper end of the water tank is provided with a water filling platform, the water filling platform is provided with a water filling port, and the overflow hole is formed in one side of the water filling platform and is not higher than the top end face of the water filling port.

Preferably, the symmetrical position in the middle of the bottom of the water adding table is also provided with a positioning column, the top of the upper liner is provided with a corresponding first fixing base body, and the positioning column is inserted into the first fixing base body water adding table and fixed on the upper liner.

Preferably, the lower end of the water tank is provided with a step limiting part, the back side surface of the lower inner container is provided with a groove, and the step limiting part is limited in the groove.

Preferably, the drainage system further comprises a first drainage pipeline, and the drainage port of the lower liner is communicated with the water inlet of the drainage pump through the first drainage pipeline.

Preferably, the anti-siphon assembly includes a first channel, a second channel, and a third channel, an upper end of the first channel, an upper end of the second channel, and a lower end of the third channel are disposed in communication, a first port is disposed at the lower end of the first channel, a second port lower than the first port is disposed at the lower end of the second channel, a third port higher than the first port is disposed at the upper end of the third channel, the first port is communicated with a water outlet of the drain pump, the second port is communicated with an outside of the machine body, and the third port is communicated with the overflow hole.

Preferably, the overflow anti-siphon system further comprises a second drain pipe and a third drain pipe, the first port is communicated with the water outlet of the drain pump through the second drain pipe, and the second port is communicated with the outside of the machine body through the third drain pipe.

Preferably, the overflow anti-siphon system further comprises an overflow pipe, and the third port is communicated with the overflow hole through the overflow pipe.

Preferably, the first channel is an arc-shaped pipeline, the second channel is positioned below the third channel, and the second channel is communicated with the third channel to form a vertical pipeline.

Preferably, an arc-shaped protection surface for guiding the washing wastewater to the second channel is provided at the upper end of the first channel, and the arc-shaped protection surface extends from the upper end of the first channel to the upper end of the second channel.

Preferably, a one-way valve is provided in the third passage.

Preferably, the one-way valve comprises a valve body with a valve cavity and a movable valve core which is positioned in the valve cavity and can move up and down;

a vent gap is formed between the vertical side wall of the valve body and the inner side wall of the third channel, and the top side wall of the valve body separates the lower tail end of the third channel from the third port;

the top side wall, the bottom side wall and the vertical side wall of the valve body are respectively provided with an upper air hole, a lower air hole and an air hole, and the upper air hole, the lower air hole and the air hole are communicated with the valve cavity;

the check valve is in a ventilation state when the movable valve core is located at a first position for sealing the lower air hole in the valve cavity, and the check valve is in a sealing state when the movable valve core is located at a second position for sealing the upper air hole in the valve cavity.

Preferably, the bottom of the valve body is provided with a group of guide plates which are arranged downwards and oppositely open in an extending mode, and the lower air hole is located between the guide plates.

Preferably, the bottom side wall of the valve cavity is provided with a support part with an upper tail end in a cambered surface, and the upper tail end of the support part is in contact connection with the bottom of the movable valve core when the check valve is in a ventilation state.

Preferably, the number of the lower air holes is plural, and the plural lower air holes are uniformly distributed on the peripheral side of the support portion.

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model discloses an increase overflow anti-siphon system in dish washer, anti-siphon subassembly through tee bend structure links to each other drainage system, water supply system and organism outside organic, can utilize anti-siphon subassembly to solve the problem that the water tank takes place the overflow when adding water for water supply system, and can utilize anti-siphon subassembly to avoid producing the negative pressure and take place the siphonage of washing waste water when utilizing drainage system discharge washing waste water again, overall structure is simple, the reliability is high and the assembly of being convenient for.

Drawings

Fig. 1 is a perspective view of a dishwasher showing only a part of a housing.

Fig. 2 is a schematic structural view corresponding to the front view of fig. 1.

Fig. 3 is a schematic cross-sectional view of a water tank.

Fig. 4 is a schematic view of a full-section structure of the anti-siphon assembly.

Fig. 5 is a schematic perspective view of the upper inner container.

Fig. 6 is a schematic structural view of the bottom surface of the lower liner.

Detailed Description

To further clarify the technical solutions and effects adopted by the present application to achieve the intended purpose, the following detailed description is given with reference to the accompanying drawings and preferred embodiments according to the present application. In the following description, different "one embodiment" or "an embodiment" refers to not necessarily the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

As shown in fig. 1 to 4, the dishwasher includes a body 1, a washing system, a water supply system for supplying water to the washing system, a drain system for draining the washing water in the washing system out of the body 1, and an overflow anti-siphon system for preventing the water supply system from overflowing when water is supplied and preventing the drain system from siphoning washing wastewater when water is drained; the washing system at least comprises an upper inner container 2 and a lower inner container 5 communicated with the upper inner container 2, and the lower inner container 5 is arranged on the bottom surface of the upper inner container 2; the water supply system at least comprises a water tank assembly 3, the water tank assembly 3 comprises a water tank 32, a water adding platform 31 arranged on the water tank 32 and a water outlet 33 arranged at the bottom of the water tank 32, the water outlet 33 is communicated with a water inlet of the lower liner 5, a water adding port 311 convenient for manual water adding and an overflow hole 312 which is positioned at one side of the bottom of the water adding platform 31 and is not higher than the top end face of the water adding port 311 are arranged on the water adding platform 31; the drainage system at least comprises a drainage pump 10 fixed on the bottom surface of the lower inner container 5, and a water inlet of the drainage pump 10 is communicated with a drainage outlet of the lower inner container 5; the overflow anti-siphon system comprises an anti-siphon assembly 6 fixed on the lower liner 2, and the anti-siphon assembly 6 is communicated with the water outlet of the drainage pump 10. And anti-siphon subassembly 6 is linked together with overflow hole 312 and anti-siphon subassembly 6 is located the below of overflow hole 312, makes like this that the water that overflows from overflow hole 312 can be discharged away through anti-siphon subassembly 6, and overflow hole 312 lets anti-siphon subassembly 6 and organism 1 outside atmosphere be linked together thereby avoid producing the negative pressure in anti-siphon subassembly 6 when the dish washer drainage and lead to taking place washing waste water siphon.

Specifically, the anti-siphon assembly 6 includes a first channel 61, a second channel 62 and a third channel 63, an upper end of the first channel 61, an upper end of the second channel 62 and a lower end of the third channel 63 are disposed in communication, the lower end of the first channel 61 is provided with a first port 611, the lower end of the second channel 62 is provided with a second port 621 lower than the first port 611, the upper end of the third channel 63 is provided with a third port 631 higher than the first port 611, the first port 611 is communicated with the water outlet of the drain pump 10, the second port 621 is communicated with the outside of the machine body 1, and the third port 631 is communicated with the overflow hole 312.

In a preferred embodiment, the drainage system further comprises a first drainage pipeline 7, and the drainage port of the lower liner 5 is communicated with the inlet of the drainage pump 10 through the first drainage pipeline 7.

In a preferred embodiment, the overflow anti-siphon system further includes an overflow pipe 4, a second drain pipe 8 and a third drain pipe 9, the first port 611 communicates with the outlet of the drain pump 10 through the second drain pipe 8, the second port 621 communicates with the outside of the machine body 1 through the third drain pipe 9, and the third port 631 communicates with the overflow hole 312 through the overflow pipe 4.

When the water in the water tank 32 is enough, if the water is continuously added into the water tank 32 through the water adding port 311, the excess water overflows from the overflow hole 312, enters the third port 631 of the anti-siphon component 6 along the overflow pipeline 4, and is finally discharged outside the machine body 1 from the second port 621 of the anti-siphon component 6, so that the anti-overflow effect is achieved, and the water overflowing in the water tank 32 cannot flow into the machine body 1, so that potential use safety hazards are caused.

When the dishwasher finishes the stage of the dish washing process, the drain pump 10 operates, and the washing wastewater in the lower liner 5 flows into the drain pump 10 from the water outlet of the lower liner 5 through the first drain pipe 7, then flows into the first port 611 of the anti-siphon assembly 6 from the water outlet of the drain pump 10 through the second drain pipe 8, and because the second port 621 is located lower than the first port 611 and the third port 631, the washing wastewater flows out from the second port 621 after flowing into the anti-siphon assembly 6 from the first port 611, and is finally discharged to a designated place outside the machine body 1 by the third drain pipe 9 (for example, one end of the third drain pipe 9 is inserted into a sewer inlet of the use environment, and the washing wastewater is finally discharged to a sewer). In addition, in the process of discharging the washing wastewater through the anti-siphon assembly 6, since the first port 611, the second port 621 and the third port 631 of the anti-siphon assembly 6 are all communicated with each other, the third port 631 is higher than the first port 611 and the second port 621, and the third port 631 is communicated with the overflow hole 312 through the overflow pipe 4, the overflow hole 312 is communicated with the atmosphere outside the machine body 1 when the non-added water overflows, and therefore, in the process of discharging the washing wastewater through the anti-siphon assembly 6, the third port 631 is communicated with the atmosphere outside the machine body 1 through the overflow pipe 4 and the overflow hole 312, so that negative pressure does not occur inside the anti-siphon assembly 6, and the washing wastewater can be smoothly discharged through the anti-siphon assembly 6 without a siphon phenomenon of reversely flowing into the lower liner 5.

Again as shown in connection with fig. 4. The integral structure of the anti-siphon component 6 is a three-way structure. The first channel 61 is an arc-shaped pipe, and the arc-shaped pipe can guide the washing wastewater entering from the first port 611 to smoothly flow into the second channel 62. The second channel 62 is located below the third channel 63, the second channel 62 and the third channel 63 are communicated to form a vertical pipeline, and this structure is favorable for the washing wastewater entering the second channel 62 and overflowing into the third channel 63 to be smoothly discharged from the second port 621, and the washing wastewater entering the second channel 62 is prevented from flowing back and flowing out of the third port 631. And, the upper end of the first channel 61 is further provided with an arc-shaped protection surface 612 extending to the upper end of the second channel 62, and the arc-shaped protection surface 61 can guide the washing wastewater to smoothly flow into the second channel 62 to avoid backflow, so that the drainage smoothness of the anti-siphon assembly 6 is improved.

Furthermore, in order to prevent the washing wastewater from entering the third channel 63 and filling the third channel 63 during the process of discharging the washing wastewater through the anti-siphon assembly 6 to close the third channel 63 such that the second channel 62 cannot communicate with the external atmosphere through the third channel 63, in a preferred embodiment, a check valve for ensuring that the third port 631 is in communication with the second channel 62 to prevent the washing wastewater from flowing from the second channel 62 to the third port 631 is provided in the third channel 63.

Specifically, the check valve includes a valve body 64 having a valve cavity 641 and a movable valve core 65 located in the valve cavity 641 and capable of moving up and down, a vent gap 632 is provided between a vertical side wall of the valve body 64 and an inner side wall of the third channel 63, a top side wall of the valve body 64 separates a lower end of the third channel 63 from the third port 631, a top side wall, a bottom side wall and a vertical side wall of the valve body 64 are respectively provided with an upper air hole 642, a lower air hole 643 and a vent hole 644, and the upper air hole 642, the lower air hole 643 and the vent hole 644 are all communicated with the valve cavity 641; when the washing wastewater in the second channel 62 does not flow back into the third channel, the movable valve core 65 is in the first position for closing the lower vent 643 in the valve cavity 641, so that the check valve is in the venting state; when the wash wastewater in the second channel 62 flows backward into the third channel 63, the movable valve element 65 is in the second position in the valve cavity 641 for closing the upper air hole 642, so that the check valve is in a closed state.

The movable valve core 65 is a light-weight, smooth-surfaced, foamable material, preferably a cylinder or a sphere, so that the movable valve core 65 can move up and down in the valve cavity 641.

Specifically, when no backflow of the washing wastewater in the second channel 62 into the third channel 63 occurs, the movable valve core 65 is located at the first position in the valve cavity 641 where the lower vent 643 is closed by its own gravity, so that the third port 631 of the third channel 63 passes through the upper vent 642, the valve cavity 641, the vent gap 632 and the lower end of the third channel 63 to allow the upper end of the second channel 62 to be communicated with the external atmosphere of the machine body 1, thereby preventing a siphon due to negative pressure. When the washing wastewater in the second channel 62 flows backward into the third channel 63 during the process of discharging the washing wastewater from the dishwasher, the backward-flowing washing wastewater generates an upward thrust to the movable valve core 65 from the lower air hole 643 from bottom to top to push the movable valve core 65 to float upward in the valve cavity 641, so that the movable valve core 65 is finally switched to the second position for sealing the upper air hole 642, the check valve is switched from the ventilation state to the sealing state, the washing wastewater is prevented from flowing into the third port 631 of the third channel 63 through the check valve, and the washing wastewater is prevented from flowing backward into the water tank 32 through the check valve; moreover, after the movable valve core 65 is at the second position, the washing wastewater cannot pass through the check valve to cause the washing wastewater to fall back under the action of its own gravity, so that the thrust on the movable valve core 65 is reduced, the movable valve core 65 falls back in the valve cavity 641 by its own gravity, and the movable valve core 65 can be returned to the ventilation state immediately without closing the upper air hole 642, so as to avoid the siphon phenomenon.

It can be appreciated that when the valve cavity 641 is cylindrical with a full circular angle, the friction between the movable valve core 65 and the valve cavity 641 is relatively small, which is more beneficial for the movable valve core 65 to float upwards or downwards in the valve cavity 641. Moreover, the bottom side wall of the valve cavity 641 is provided with a support portion 645 with an arc-shaped upper end, and when the check valve is in a ventilation state, the upper end of the support portion 645 is in contact connection with the bottom of the movable valve element 65, so that the contact area between the upper end and the bottom of the movable valve element is reduced, friction is reduced, the flexibility of the movable valve element 65 is improved, and the whole sensitivity of the check valve is improved. Furthermore, the number of the lower air holes 643 is plural, and the plural lower air holes 643 are uniformly distributed on the circumferential side of the supporting portion 645 to provide a uniform floating thrust to all positions at the bottom of the movable valve core 65, so as to ensure that the movable valve core 65 is not jammed in the valve cavity 641 due to uneven stress, thereby improving the reliability of the check valve. Meanwhile, the anti-siphon assembly 6 is provided with the plurality of positioning holes 66, so that screws can be conveniently screwed into the positioning screw holes 513, and the anti-siphon assembly 6 is fixed on the upper liner 2.

In addition, the bottom of the valve body 64 is provided with a group of guide plates 646 which are downward and oppositely arranged in an opening manner, the guide plates 646 are positioned between the guide plates 646, the pressure generated when the washing wastewater flows back into the third channel 63 is guided to the lower air holes 643 through the guide plates 646, and the thrust generated on the movable valve core 65 through the lower air holes 643 is more favorably realized so as to improve the sensitivity and the reliability of the check valve.

Referring again to fig. 3 and 5, the water adding table 31 is located at the top end of the water tank 32, and the water outlet hole 33 is located at the bottom end of the water tank 32. Moreover, two positioning columns 313 are symmetrically arranged in the middle of the bottom of the water adding table 31, and the positioning columns 313 are annular, so that the water tank 32 can be conveniently fixed on the upper inner container 2; the upper liner 2 is provided with a plurality of uniform reinforcing ribs, the top of the upper liner is provided with a first fixing base body 21 for fixing the water tank 32, the first fixing base body 21 is circular, the size of the first fixing base body is slightly larger than that of the positioning column 313, the positioning column 313 can be exactly wrapped in the first fixing base body, the water tank 321 is prevented from inclining backwards due to gravity or other reasons, and therefore the upper tail end of the water tank 32 is matched and fixed with the first fixing base body 21 of the upper liner 2 through the positioning column 313 of the water adding table 31. In addition, a step stopper 321 is formed at the lower end of the water tank 32, and the step stopper 321 is formed to facilitate insertion of the water tank 32 into the lower inner container 5, and the upper end of the water tank 32 is fixed by inserting the step stopper 321 into the lower inner container 5.

In addition, the lower side bottom of the upper inner container 2 is distributed with a second fixing base 22, and the second fixing base 22 is matched and connected with the positioning hole 66 of the anti-siphon component 6, so that the anti-siphon component 6 is prevented from being shifted due to pulling. Furthermore, a plurality of third positioning base bodies 23 are uniformly distributed at the bottom of the upper liner 2, and the third positioning base bodies are columnar, so that the upper liner 2 is conveniently connected with the lower liner 5 through the third positioning base bodies 23, and the lower liner 5 is fixed on the bottom surface of the upper liner 2.

As further shown in connection with fig. 1, 2 and 6. The drain pump 10 is composed of a pump cover and a pump body, the pump cover is connected with the pump body through a buckle, a water inlet of the drain pump 10 and a water outlet of the drain pump 10 are both arranged on the pump cover, and the water inlet of the drain pump 10 and the water outlet of the drain pump 10 are vertically distributed on a central line. The drain pump 10 is fixed in the bottom surface of inner bag 5 down, and the bottom surface of inner bag 5 is equipped with first supporting seat 531, pump fixing base 532 and second supporting seat 533 down, and first supporting seat 531 provides the vibration that supports in order to reduce the drain pump during operation to the pump body, and pump fixing base 532 fixes drain pump 10 on the bottom surface of inner bag 5 down in order to prevent the offset, and second supporting seat 533 provides the support in order to prevent to lead to the pump cover to take place to drop from the pump body because of the vibration in the course of the work to the pump cover.

As shown in fig. 6, the side surface of the lower liner 5 is provided with a third fixing base 511, a fourth fixing base 512, a positioning screw 513, an arc fixing base 514, a fifth fixing base 515 and a through hole 516. The third fixing base 511 is sheet-shaped, and the third fixing base 511 is matched with the second fixing base 22 distributed on the upper liner 2 to limit the anti-siphon component 6; the fourth fixed base 512 is in a half-turn shape, and further limits the lower side surface of the anti-siphon component 6; the positioning screw hole 513 is used for positioning and fixing the anti-siphon assembly 6, and the arc fixing base 514 is used for supporting the bottom of the anti-siphon assembly 6 to prevent noise generated by severe vibration of the anti-siphon assembly 6 due to the influence of the drainage pump 10; the fifth fixing base 515 and the fourth fixing base 512 are the same in shape, and limit and fix the anti-siphon component 6 together with the fourth fixing base 512, so that the component 6 is prevented from vibrating to generate noise. In addition, through grooves 515 evenly distributed on the top end surface of the lower liner 5 are matched with the third positioning matrixes 23 on the upper liner 2 in a screw mode to form fastening fit. The back side surface of the lower inner container 5 is provided with a groove, the inner dimension of the groove is just matched with the outer dimension of the step limiting part 321 of the water tank 32, so that the step limiting part 321 is limited by the groove, and the lower tail end of the water tank 32 is inserted into the lower inner container 5. Therefore, the assembly between each part of the dishwasher is simple so as to improve the production, manufacture, disassembly and maintenance efficiency.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A dishwasher comprises a machine body, a washing system, a water supply system and a drainage system;

the washing system at least comprises an upper inner container and a lower inner container communicated with the upper inner container, and the lower inner container is arranged on the bottom surface of the upper inner container;

the water supply system at least comprises a water tank assembly, the water tank assembly comprises a water tank with an overflow hole and a water outlet hole, and the water outlet hole is communicated with the water inlet of the lower inner container;

the drainage system at least comprises a drainage pump fixed on the bottom surface of the lower inner container, and a water inlet of the drainage pump is communicated with a water outlet of the lower inner container;

the anti-siphon dishwasher is characterized by further comprising an overflow anti-siphon system, wherein the overflow anti-siphon system comprises an anti-siphon component communicated with the water outlet of the drainage pump, the anti-siphon component is communicated with the overflow hole, and the anti-siphon component is located below the overflow hole.

2. The dishwasher of claim 1, wherein the upper end of the water tank is provided with a water filling table having a water filling port, and the overflow hole is provided at one side of the water filling table at a position not higher than a top end surface of the water filling port.

3. The dishwasher of claim 2, wherein the water adding table is further provided with positioning columns at symmetrical positions in the middle of the bottom, the top of the upper inner container is provided with a corresponding first fixing base, and the positioning columns are inserted into the first fixing base and fixed on the upper inner container.

4. The dishwasher of claim 1, wherein the lower end of the water tank is provided with a step limiting part, the back side surface of the lower inner container is provided with a groove, and the step limiting part is limited in the groove.

5. The dishwasher of claim 1, wherein the drain system further comprises a first drain pipe, and the drain opening of the lower tub is communicated with the inlet of the drain pump through the first drain pipe.

6. The dishwasher of any one of claims 1 to 5, wherein the anti-siphon assembly comprises a first channel, a second channel and a third channel, an upper end of the first channel, an upper end of the second channel and a lower end of the third channel are provided to communicate with each other, the lower end of the first channel is provided with a first port, the lower end of the second channel is provided with a second port positioned lower than the first port, the upper end of the third channel is provided with a third port positioned higher than the first port, the first port communicates with the water outlet of the drain pump, the second port communicates with the outside of the housing, and the third port communicates with the overflow hole.

7. The dishwasher of claim 6, wherein the overflow anti-siphon system further comprises a second drain pipe and a third drain pipe, the first port communicates with the water outlet of the drain pump through the second drain pipe, and the second port communicates with the outside of the machine body through the third drain pipe.

8. The dishwasher of claim 6, wherein the overflow anti-siphon system further comprises an overflow conduit, the third port being in communication with the overflow aperture through the overflow conduit.

9. The dishwasher of claim 6, wherein the first channel is an arc-shaped duct, the second channel is located below the third channel, and the second channel and the third channel are communicated as a vertical duct.

10. The dishwasher of claim 6, wherein an arc-shaped shielding surface for guiding the washing wastewater to the second passage is provided at an upper end of the first passage, the arc-shaped shielding surface extending from the upper end of the first passage toward the upper end of the second passage.

11. The dishwasher of claim 6, wherein a check valve is provided in the third passage.

12. The dishwasher of claim 11, wherein the one-way valve comprises a valve body having a valve chamber and a movable valve element located in the valve chamber for up and down movement;

13. The dishwasher of claim 12, wherein the bottom of the valve body is provided with a plurality of downwardly facing oppositely open baffles, the lower air holes being located between the baffles.

14. The dishwasher of claim 12, wherein the bottom side wall of the valve chamber is provided with a support portion having an upper end in a curved surface, and the upper end of the support portion is in contact with the bottom of the movable valve element when the check valve is in the ventilating state.

15. The dishwasher of claim 14, wherein the number of the lower air holes is plural, and the plural lower air holes are uniformly distributed on the circumferential side of the support portion.