CN113207730B - Self-cleaning and automatic water-changing pet water dispenser - Google Patents

Abstract

The invention provides a self-cleaning and automatic water-changing pet water dispenser which comprises a body, a self-cleaning structure and an automatic water-changing structure. The pet water dispenser capable of cleaning and automatically changing water is simple in structure and easy and convenient to install. Not only can automatically clean the drinking bowl, but also can drain the sewage containing dust, pet hair and food residues, and can inject new purified water into the drinking bowl.

Description

A pet drinking fountain with self-cleaning and automatic water changing function

Technical Field

The invention relates to the technical field of pet drinking water, and in particular to a pet drinking water machine capable of self-cleaning and automatic water changing.

Background Art

As people's living standards improve, more and more families keep pets. As good companions in people's lives, cats and dogs are becoming more and more important to people in terms of food hygiene. Water is an indispensable part of food, and people need to regularly replace clean drinking water for their pets. With the development of economy and technology, there are now automatic feeders and pet drinking fountains to free up manpower.

There is always a layer of slippery mucus on the wall of pet water bowls. Studies have found that this is actually bacterial biofilm (or bacterial biofilm), which refers to a large number of bacterial aggregation membranes formed by bacteria adhering to the contact surface, secreting polysaccharide matrix, fibrin, lipid protein, etc., and wrapping themselves in it. Bacterial biofilm is a life phenomenon that bacteria adapt to the natural environment and is conducive to survival. It will continuously attract, reproduce, and differentiate more bacteria. The bacterial biofilm on the wall of the pet water bowl is mostly formed by dust and bacteria in the environment, as well as bacteria in the mouth when the pet drinks water, and the source cannot be eradicated. The higher the temperature, the faster the bacterial biofilm grows.

Therefore, stainless steel pet drinking bowls need to be cleaned at least every day, rather than simply adding water. Otherwise, the bacterial content in the water will be greatly increased, which may affect the pet's desire to drink water, or even cause the pet to suffer from indigestion, urinary system diseases, etc.

At present, the most common pet drinking fountains are: one is to use an inverted bucket. When the water level in the drinking bowl is lower than a certain value, gravity and air pressure are used to replenish drinking water; the other is to use a water circulation structure to let the water in the water tank flow out in a fountain-like manner, creating a visual effect of "living water" to attract pets to drink. In fact, the circulating water source is not new. Even if a filter is added inside the circulating water tank, the filtered dirt will still be immersed in the water, causing water pollution. The disadvantages of this structure are very obvious. Its water circulation structure is complex and there are many dead corners, which are hotbeds for bacterial reproduction. Moreover, due to the complex structure, it cannot be completely cleaned even by manual cleaning.

The pet water dispensers commonly used in the prior art mainly realize the functions of replenishing water or attracting pets, and do not have the functions of self-cleaning and automatic water replacement. If the pet owner is busy or even on a business trip, such a water dispenser basically cannot meet the requirements of a healthy water source.

Summary of the invention

The objects of the present invention are:

In view of the shortcomings of the prior art, a pet drinking fountain with self-cleaning and automatic water changing functions is provided, which has a simple structure and is easy and convenient to install. It can not only automatically clean the drinking bowl, but also drain away the sewage containing dust, pet hair, and food residues, and can inject new clean water into the drinking bowl.

The purpose of the present invention can be achieved through the following technical solutions:

A self-cleaning and automatic water-changing pet drinking water machine comprises a machine body, a self-cleaning structure and an automatic water-changing structure; the machine body comprises a clean water chamber, a sewage chamber, a stainless steel pet drinking water bowl and a controller; the self-cleaning structure comprises an ultrasonic transducer attached to the bottom of the stainless steel pet drinking water bowl; the automatic water-changing structure comprises a clean water injection structure and a sewage discharge structure; the clean water injection structure comprises a water pipe, a water pump or a solenoid valve, and a water injection faucet which are sequentially connected to the clean water chamber; the sewage discharge structure comprises a drain port opened at the bottom of the stainless steel pet drinking water bowl, a drain pipe connecting the drain port and the sewage chamber, the drain pipe is bent downwardly in a U shape below the drain port, penetrates into the sewage chamber from the bottom of the sewage chamber, and is vertically arranged in the sewage chamber from bottom to top); in a preferred embodiment, the drain pipe can also be bent downwardly in a U shape below the drain port, then bend upwardly in an inverted U shape, the top of the inverted U-shaped section is higher than the top of the stainless steel pet drinking water bowl, then bend downwardly in a U shape again, penetrates into the sewage chamber from the bottom of the sewage chamber, and is vertically arranged in the sewage chamber from bottom to top. The inverted U-shaped section of the drain pipe is also provided with a water bowl sensing liquid level sensor for monitoring the water level of the stainless steel pet drinking bowl. The starting point of the inverted U-shaped section needs to be more than 2 cm higher than the highest water level designed for the stainless steel pet drinking bowl, so that there is enough space to place the water bowl sensing liquid level sensor.

The sewage discharge structure also includes an exhaust port opened at the upper part or top of the sewage chamber, a one-way exhaust valve installed outside the exhaust port so that the gas in the sewage chamber can only go out but not in, and an exhaust pipe vertically arranged inside the sewage chamber, one end of the exhaust port of the exhaust pipe is arranged at the upper part of the sewage chamber, and the other end of the exhaust pipe passes through the bottom of the sewage chamber and is connected to an air pump arranged under the bottom plate of the sewage chamber. In a preferred embodiment, the one-way exhaust valve is a flexible sheet structure added to the top of the exhaust port of the sewage chamber, and only one side of the flexible sheet structure is fixed to the top of the sewage chamber and its fixed connection does not block the exhaust port of the sewage chamber.

The body also includes a vertical equipment cavity sandwiched between the clean water cavity and the sewage cavity, and the vertical equipment cavity is used to accommodate components of the clean water injection structure and the sewage discharge structure that are higher than the stainless steel pet drinking bowl and are not arranged in the clean water cavity and the sewage cavity; the water injection faucet is arranged above the stainless steel pet drinking bowl outside the vertical equipment cavity.

The body also includes a transverse equipment cavity arranged below the clean water cavity, the sewage cavity and the stainless steel pet drinking bowl, and the transverse equipment cavity is used to accommodate components of the clean water injection structure and the sewage discharge structure below the clean water cavity, the sewage cavity and the stainless steel pet drinking bowl.

The clean water injection structure also includes a flow meter arranged between the water pump or the electromagnetic valve and the water injection faucet.

A filtering device is also provided inside the water purification chamber.

The air pump is also provided with an air pump exhaust pipe.

At least one ultraviolet disinfection lamp is also arranged in the vertical equipment cavity, and the wall surface of the vertical equipment cavity connecting with the clean water cavity and the sewage cavity is a transparent wall surface.

A high-level inductive liquid level sensor for monitoring the high water level of the sewage cavity is provided at the upper part of the vertical equipment cavity, and a low-level inductive liquid level sensor for monitoring the low water level of the clean water cavity is provided at the lower part of the equipment cavity.

The controller is used to control an ultrasonic transducer, a water pump or a solenoid valve, an air pump, a flow meter, a water bowl inductive liquid level sensor, a high-level inductive liquid level sensor, a low-level inductive liquid level sensor and an ultraviolet disinfection lamp.

The end of the drainage pipe located at the upper part of the sewage chamber is provided with a detachable filter head.

The end of the air extraction pipe located at the upper part of the sewage chamber is provided with an inverted U-shaped pipe section and a buoyancy valve. The main structure of the buoyancy valve is a cylindrical cavity with openings at both ends, and its upper end is connected to the inverted U-shaped pipe section at the end of the air extraction pipe. Several through holes are opened on the upper part of the side wall of the cylindrical cavity. A float is installed inside the cylindrical cavity, which can block the opening of the inverted U-shaped pipe section and has a diameter larger than the opening at the lower end of the cylindrical cavity.

The beneficial effects of the present invention are:

1. It can automatically clean the stainless steel pet drinking bowl and remove the bacterial biofilm attached to the wall of the drinking bowl through ultrasonic waves, which is very effective.

2. It can drain away sewage containing dust, pet hair, and food residues. It cleverly uses the principle of negative pressure to pump away sewage. It does not require a water pump that is prone to clogging. Small water pumps cannot handle hair, food residues, and possible solid particles. The internal structure of the water pump is complex and easy to breed bacteria. The design of the drain pipe with multiple U-shaped sections can reduce the amount of water stored in the drain pipe as much as possible. The stainless steel pet drinking bowl is made of metal material, and the inductive liquid level sensor cannot be used. The U-shaped tube installation inductive liquid level sensor section is non-metallic material, and due to the principle of communicating vessels, the water level of the drinking bowl is obtained by measuring the water level of the U-shaped tube. Because the sewage outlet in the sewage chamber, that is, the outlet of the drain pipe, is above the liquid level, the sewage cannot flow back into the drinking bowl, and the drinking bowl does not require a complex water seal, and it is easier to drain large volumes of dirt.

3. New clean water can be poured into the drinking water bowl instead of the traditional recirculation of "old water".

4. You can set the water changing frequency and cleaning frequency by yourself through the settings of the controller. When the owner has high health requirements, you can set it to clean and change the water several times a day. When the owner is on a business trip, you can set it to clean and change the water once a day to extend the use time of a box of purified water.

5. Simple structure, cost saving, simple and convenient installation, easy for later maintenance and deep cleaning, easy for production and promotion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the main structure of the present invention.

FIG. 2 is one of the schematic diagrams of the appearance of the present invention.

FIG. 3 is a second schematic diagram of the appearance of the present invention.

FIG. 4 is one of the partial structural schematic diagrams of the present invention.

FIG. 5 is a second schematic diagram of a partial structure of the present invention.

FIG. 6 is a third schematic diagram of a partial structure of the present invention.

FIG. 7 is a fourth schematic diagram of a partial structure of the present invention.

FIG. 8 is a schematic diagram of a filter head component of the present invention.

FIG. 9 is a second schematic diagram of the filter head component of the present invention.

FIG. 10 is a schematic diagram of a buoyancy valve component of the present invention.

FIG. 11 is a second schematic diagram of the buoyancy valve component of the present invention.

FIG. 12 is a fifth schematic diagram of a partial structure of the present invention.

in:

100. Body;

101. Water purification chamber;

102. Sewage cavity;

103. Stainless steel pet drinking bowl;

104. Controller;

105. Vertical equipment cavity;

106. Transverse equipment cavity;

107. Filtering device;

108. Water bowl sensing liquid level sensor;

109. Ultraviolet disinfection lamp;

110. High-level sensing liquid level sensor;

111. Low level sensing liquid level sensor;

112. Exhaust hole;

201. Ultrasonic transducer;

311. Water pipes;

312. Water pump or solenoid valve;

313. Water filling tap;

314. Flow meter;

321. Drainage outlet;

322. Drain pipe;

323, inverted U-shaped segment;

324, exhaust port;

325. One-way exhaust valve;

326, exhaust pipe;

327. Air pump;

328. Air pump exhaust pipe;

329, filter head;

330, inverted U-shaped pipe section;

331, buoyancy valve;

332, through hole;

333. Float.

DETAILED DESCRIPTION

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in FIG1 , the present invention provides a self-cleaning and automatic water-changing pet drinking water machine, comprising a machine body 100, a self-cleaning structure and an automatic water-changing structure. As shown in FIG4 , the machine body 100 comprises a clean water chamber 101, a sewage chamber 102, a stainless steel pet drinking water bowl 103, and a controller 104. The self-cleaning structure comprises an ultrasonic transducer 201 attached to the bottom of the stainless steel pet drinking water bowl 103.

The automatic water changing structure includes a clean water injection structure and a sewage discharge structure. As shown in FIG4 , the clean water injection structure includes a water pipe 311, a water pump or a solenoid valve 312, and a water injection tap 313 that are sequentially connected to the clean water chamber 101. As shown in FIG6 , the sewage discharge structure includes a drain port 321 opened at the bottom of the stainless steel pet drinking water bowl 103, and a drain pipe 322 connecting the drain port 321 and the sewage chamber 102.

As shown in FIG. 12 , in one embodiment of the present invention, the drain pipe 322 bends downward into a U shape below the drain outlet 321 and penetrates into the sewage chamber 102 from the bottom of the sewage chamber 102 , and is vertically arranged in the sewage chamber 102 from bottom to top.

As shown in FIG. 7 and FIG. 1 , in one embodiment of the present invention, the drain pipe 322 bends downwardly into a U-shape below the drain outlet 321, and then bends upwardly into an inverted U-shape, the top of the inverted U-shaped section 323 is higher than the top of the stainless steel pet drinking water bowl 103, and then bends downwardly into a U-shape and penetrates into the sewage chamber 102 from the bottom of the sewage chamber 102, and is vertically arranged in the sewage chamber 102 from bottom to top. As shown in FIG. 7 , the starting point of the inverted U-shaped section 323 needs to be more than 2 cm higher than the highest water level designed for the stainless steel pet drinking water bowl 103, so that there is enough space to place the water bowl sensing liquid level sensor 108. The inverted U-shaped section 323 of the drain pipe 322 is also provided with a water bowl sensing liquid level sensor 108 for monitoring the water level of the stainless steel pet drinking water bowl 103. As shown in FIG. 1 , the end of the drain pipe 322 located at the upper part of the sewage chamber 102 is provided with a detachable filter head 329 for collecting residues, intercepting hair, etc. A slow-release sterilization tablet can be placed in the sewage cavity 102 to inhibit bacteria in the sewage cavity. As shown in Figures 8 and 9, the filter head 329 is a structure with a cavity and multiple through holes.

As shown in FIG2 , the sewage discharge structure further includes an exhaust port 324 provided at the upper part or top of the sewage chamber 102, a one-way exhaust valve 325 installed outside the exhaust port 324 to allow the gas in the sewage chamber 102 to only go out but not in, and an air extraction pipe 326 vertically provided inside the sewage chamber 102. As shown in FIG1 , one end of the air extraction port of the air extraction pipe 326 is provided at the upper part of the sewage chamber 102, and the other end of the air extraction pipe 326 passes through the bottom of the sewage chamber 102 and is connected to an air pump 327 provided under the bottom plate of the sewage chamber 102. As shown in FIG4 , an air pump exhaust pipe 328 is also provided on the air pump 327, and the air pump exhaust pipe 328 described here is usually a component provided by the air pump and is used to finally discharge the gas.

As shown in FIG1 , the end of the air extraction pipe 326 located at the upper part of the sewage chamber 102 is provided with an inverted U-shaped pipe section 330 and a buoyancy valve 331. As shown in FIG10 , the main structure of the buoyancy valve 331 is a cylindrical cavity with openings at both ends, the upper end of which is connected to the inverted U-shaped pipe section 330 at the end of the air extraction pipe 326, and the upper part of the side wall of the cylindrical cavity is provided with several through holes 332. As shown in FIG11 , a float 333 is installed inside the cylindrical cavity, which can block the opening of the inverted U-shaped pipe section 330 and has a diameter larger than the opening at the lower end of the cylindrical cavity. When the water is full, the buoyancy valve 331 can prevent water from entering the air pump 327. When the inductive liquid level sensor fails or other unexpected problems occur, the buoyancy valve 331 is a second layer of protection.

As shown in FIG1 , the machine body 100 further includes a vertical equipment cavity 105 sandwiched between the clean water cavity 101 and the sewage cavity 102. As shown in FIG5 and FIG6 , the vertical equipment cavity 105 is used to accommodate components of the clean water injection structure and the sewage discharge structure that are higher than the stainless steel pet drinking water bowl 103 and are not arranged in the clean water cavity 101 and the sewage cavity 102; the water injection faucet 313 is arranged above the stainless steel pet drinking water bowl 103 outside the vertical equipment cavity 105.

As shown in FIG1 , the machine body 100 further includes a transverse equipment cavity 106 disposed below the clean water cavity 101, the sewage cavity 102 and the stainless steel pet drinking water bowl 103. As shown in FIG4 , FIG4 is a schematic diagram of the structure from an upward perspective after the panel of the transverse equipment cavity 106 is removed. The transverse equipment cavity 106 is used to accommodate the components of the clean water injection structure and the sewage discharge structure that are lower than the clean water cavity 101, the sewage cavity 102 and the stainless steel pet drinking water bowl 103. As shown in FIG3 , the rear wall of the transverse equipment cavity 106 can also be provided with an exhaust through hole 112 that is connected to the air pump exhaust pipe 328 and is used for gas discharge.

The vertical device cavity 105 and the horizontal device cavity 106 are mainly used to hide components, so that the appearance of the water dispenser looks more concise. While hiding the components, they also protect the components and extend their service life.

As shown in Figure 5 or Figure 6, at least one ultraviolet disinfection lamp 109 is also provided in the vertical device cavity 105, and the wall surface of the vertical device cavity 105 connecting the water purification cavity 101 and the sewage cavity 102 is a transparent wall surface. The transparent wall surface is set to allow ultraviolet rays to pass through, and an acrylic board surface is preferably used.

As shown in Figure 6, a high-level sensing liquid level sensor 110 for monitoring the high water level of the sewage chamber is provided in the upper part of the vertical equipment cavity 105. As shown in Figure 5, a low-level sensing liquid level sensor 111 for monitoring the low water level of the clean water chamber is provided in the lower part of the equipment cavity.

As shown in FIG. 5 , the clean water injection structure further includes a flow meter 314 disposed between a water pump or a solenoid valve 312 and a water injection tap 313 .

As shown in FIG1 , a filter device 107 is also provided inside the water purification chamber 101. FIG1 is a schematic diagram of the structure of an embodiment of the present invention. In FIG1 , the filter device 107 is composed of a panel with a middle hollow and a slot disposed transversely in the water purification chamber 101, and a filter element stuck in the middle hollow of the panel. The filter element of the filter device 107 can be a water filter element that is easy to purchase and produce on the market, such as an activated carbon filter element, and the filter element is replaced regularly by the pet owner.

As shown in Fig. 2, the one-way exhaust valve 325 is a flexible sheet structure added to the top of the sewage chamber exhaust port 324, and only one side of the flexible sheet structure is fixed to the top of the sewage chamber 102 and its fixed connection does not block the sewage chamber exhaust port 324. The flexible sheet structure can be made of a rubber sheet.

The controller 104 is used to control the ultrasonic transducer 201, the water pump or solenoid valve 312, the air pump 327, the flow meter 314, the water bowl inductive liquid level sensor 108, the high-level inductive liquid level sensor 110, the low-level inductive liquid level sensor 111 and the ultraviolet disinfection lamp 109. The control of the ultrasonic transducer 201, the water pump or solenoid valve 312, the air pump 327, the flow meter 314 and the inductive liquid level sensor can all adopt existing technologies and can be directly purchased on the market. The connection between the controller 104 and the above-mentioned components can be in the form of circuit connection, etc., and its connection line is not shown in the schematic diagram. The ultrasonic transducer 201 can be selected from the ultrasonic transducer ceramic piece (specification: 43kHz, 35W, diameter 50mm*2.6mm) produced by Shenzhen Jielit Ultrasonic Cleaning Equipment Co., Ltd. The water pump 312 can be selected from the "Yangxi" brand 6-12V-PC water pump produced by Anqing Yangxi Model Technology Co., Ltd. The air pump 327 can be a 12V micro vacuum pump (model 3035A) produced by Foshan Weilizi Electronic Technology Co., Ltd. or a 12v air pump (model 555) produced by Huangjunda Motor. The flow meter 314 can be a "Dijiang" brand small water flow sensor (model YF-S401) produced by Guangdong Zhongjiang Energy Saving Electronics Co., Ltd. The water bowl sensing liquid level sensor 108, the high-level sensing liquid level sensor 110, and the low-level sensing liquid level sensor 111 can use non-contact liquid level sensors (model: XKC-Y26-NPN (5-12V)) produced by Shenzhen Xingke Technology Co., Ltd. The controller 104 is a programmable controller for controlling the above components. The drivers of the above components can be integrated on a circuit board, and the water level and flow can be monitored through simple programming, and the time for automatic water change and automatic addition of new purified water can be set. The drivers of the above components can be provided by the manufacturer, and the programming can also be achieved through existing technology.

The working process and principle of the present invention are:

First, regarding the function of automatically cleaning the stainless steel pet drinking bowl, the bacterial biofilm attached to the wall of the drinking bowl is removed by ultrasound, and the cleaning is very effective. The pet drinking machine of the present invention is to attach an ultrasonic transducer 201 to the bottom of the stainless steel pet drinking bowl 103, and the cavitation, acceleration and straight flow of the generated ultrasonic waves in the water directly and indirectly act on the water and dirt, so that the dirt layer is dispersed, emulsified and peeled off to achieve the purpose of cleaning. The advantage of this solution is that it does not require a complex mechanical structure, is simple, reliable and safe, and will not hurt people and pets during work.

Secondly, regarding the function of draining sewage, the pet drinking fountain of the present invention utilizes a one-way exhaust valve 325 to perform a one-way sealing design on the sewage chamber 102, so that air can only go out but not in. The ports of the drain pipe 322 and the exhaust pipe 326 in the sewage chamber 102 are both above the designed liquid level. By pumping out the air inside the sewage chamber 102, a negative pressure is formed, and the atmospheric pressure will press the sewage in the stainless steel pet drinking bowl 103 into the sewage chamber 102. The pet drinking fountain of the present invention is designed with multiple U-shaped sections of the drain pipe 322 close to the stainless steel pet drinking bowl 103, so as to minimize the water accumulation in the pipe, and these U-shaped pipe sections are close to the water bowl and can be cleaned by ultrasonic waves. The advantage of this solution is that no water pump is required, and a small water pump cannot handle hair, food residues and possible solid particles, and the internal structure of the water pump is complex and easy to breed bacteria. In addition, because the sewage outlet in the sewage chamber 102 is above the designed liquid level, the sewage will not flow back into the stainless steel pet drinking bowl 103, and the stainless steel pet drinking bowl 103 does not need to pass through a complex water seal, and it is easier to drain large volumes of dirt.

Again, regarding the function of injecting new clean water, the pet water dispenser of the present invention allows clean water to be stored in the clean water chamber 101, and then connected to the water injection tap 313 through the water pipe 311, and the clean water is injected into the stainless steel pet drinking bowl 103 through the water pipe 311 and the water injection tap 313. The water source in the clean water chamber 101 is purified water or tap water stored in advance. A filter device 107 can be added to the clean water chamber 101, especially when tap water is used, the tap water is filtered out of harmful substances through the filter. A water pump or solenoid valve 312 is provided in the middle of the water pipe 311, and a food-grade water pump or a food-grade solenoid valve is used in the preferred embodiment to control the water flow. A water bowl sensing liquid level sensor 108 is attached to the U-shaped section of the drain pipe to monitor the water level in the water bowl. The water bowl sensing liquid level sensor 108 is monitored by the controller 104, and the time control such as timed water change and other functions are preset to ensure that the water will not overflow when the clean water is injected. A flow meter 314 may also be provided in the middle of the clean water pipeline, i.e., the water pipe 311, to monitor the amount of water injected each time.

Although the present invention is described and illustrated herein by one or more specific configurations, it is not intended to be limited to the details, since various modifications and structural changes are possible within the scope of the patent claims without departing from the spirit of the invention.

Parts of the present invention are the same as the prior art or can be implemented by using the prior art.

Claims (8)

1. A self-cleaning and automatic water-changing pet water dispenser is characterized in that: comprises a machine body (100), a self-cleaning structure and an automatic water changing structure; the machine body (100) comprises a water purifying cavity (101), a sewage cavity (102), a stainless steel pet drinking bowl (103) and a controller (104); the self-cleaning structure comprises an ultrasonic transducer (201) attached to the bottom of the stainless steel pet drinking bowl (103); the automatic water changing structure comprises a purified water injection structure and a sewage discharge structure; the water purification injection structure comprises a water pipe (311), a water pump or an electromagnetic valve (312) and a water injection tap (313) which are sequentially communicated with the water purification cavity (101); the sewage discharge structure comprises a water outlet (321) arranged at the bottom of the stainless steel pet drinking bowl (103), and a water discharge pipe (322) connected with the water outlet (321) and the sewage cavity (102), wherein the water discharge pipe (322) is bent downwards to form a U shape below the water outlet (321) and then bent upwards to form an inverted U shape, the top of the inverted U-shaped section (323) is higher than the top of the stainless steel pet drinking bowl (103), then bent downwards to form a U shape and penetrates into the sewage cavity (102) from the bottom of the sewage cavity (102), and is vertically arranged in the sewage cavity (102) from bottom to top, and the top of the water discharge pipe reaches the upper part of the sewage cavity (102); the sewage draining structure further comprises an exhaust pipe (326) vertically arranged inside the sewage cavity (102), one end of an exhaust opening of the exhaust pipe (326) is arranged on the upper portion of the sewage cavity (102), the other end of the exhaust pipe (326) penetrates out from the bottom of the sewage cavity (102) and is connected with an air pump (327) arranged below a bottom plate of the sewage cavity (102), one section of inverted U-shaped pipe section (330) and a buoyancy valve (331) are arranged at the tail end of the exhaust pipe (326) located on the upper portion of the sewage cavity (102), the main body structure of the buoyancy valve (331) is a cylindrical cavity with openings at the upper end and the lower end, the upper end of the cylindrical cavity is communicated with the inverted U-shaped pipe section (330) at the tail end of the exhaust pipe (326), a plurality of through holes (332) are formed in the upper portion of the side wall of the cylindrical cavity, and a floater (333) capable of blocking the openings of the inverted U-shaped pipe section (330) and having diameters larger than the lower end of the cylindrical cavity is arranged inside the cylindrical cavity.

2. A self-cleaning and automatic water changing pet water dispenser according to claim 1, characterized in that said body (100) further comprises a vertical equipment cavity (105) sandwiched between the water purification chamber (101) and the sewage chamber (102), said vertical equipment cavity (105) being adapted to house components of the water purification injection structure and the sewage discharge structure which are higher than the stainless steel pet water bowl (103) and which are not located in the water purification chamber (101) and the sewage chamber (102); the water injection tap (313) is arranged above the stainless steel pet drinking bowl (103) outside the vertical equipment cavity (105); the machine body (100) further comprises a transverse device cavity (106) arranged below the water purifying cavity (101), the sewage cavity (102) and the stainless steel pet drinking bowl (103), and the transverse device cavity (106) is used for accommodating parts of the water purifying injection structure and the sewage discharging structure, which are lower than the water purifying cavity (101), the sewage cavity (102) and the stainless steel pet drinking bowl (103).

3. The self-cleaning and automatic water-changing pet water dispenser according to claim 1, wherein the sewage discharge structure further comprises an exhaust port (324) arranged at the upper part or the top of the sewage chamber (102), the exhaust port (324) is an exhaust hole with the diameter smaller than 2mm, or a one-way exhaust valve (325) which can ensure that the gas in the sewage chamber (102) can not enter only is arranged above the exhaust port (324).

4. A self-cleaning and automatic water changing pet water fountain according to claim 1, characterized in that the inside of the water purifying chamber (101) is also provided with a filtering device (107).

5. The self-cleaning and automatic water-changing pet water dispenser according to claim 2 is characterized in that at least one ultraviolet disinfection lamp (109) is further arranged in the vertical equipment cavity (105), and the wall surface of the vertical equipment cavity (105) connected with the water purifying cavity (101) and the sewage cavity (102) is a transparent wall surface.

6. The self-cleaning and automatic water-changing pet water dispenser according to claim 2, wherein the upper part in the vertical equipment cavity (105) is provided with a high-level induction liquid level sensor (110) for monitoring the high water level of the sewage tank, and the lower part in the equipment cavity is provided with a low-level induction liquid level sensor (111) for monitoring the low water level of the water purifying tank.

7. A self-cleaning and automatic water changing pet water dispenser according to claim 1, 5 or 6, characterized in that the controller (104) is adapted to control an ultrasonic transducer (201), a water pump or solenoid valve (312), an air pump (327), a high level sensing level sensor (110), a low level sensing level sensor (111) and an ultraviolet disinfection lamp (109).

8. A self-cleaning and automatic water changing pet water dispenser according to claim 1, characterized in that the end of the drain pipe (322) at the upper part of the sewage chamber (102) is provided with a detachable filter head (329).