CN205658126U - Negative pressure governing system - Google Patents

Abstract

The utility model discloses a negative pressure regulating system. Including: negative pressure irrigation infiltrator, water guide pipe, liquid reservoir, air guide pipe and negative pressure regulator, wherein, one end of the water guide pipe is connected to the negative pressure irrigation infiltrator, and the other end passes through the side wall of the liquid reservoir. The liquid guide hole is connected to the liquid reservoir; the negative pressure irrigation seepage device is placed obliquely; the liquid reservoir contains water; one end of the air guide tube is connected to the liquid reservoir through the air guide hole, and the air guide hole and the liquid guide hole Located at the same level, the other end of the air guide tube is connected to the negative pressure regulator; the negative pressure regulator is composed of a sealed container and an air inlet pipe. The air inlet pipe is a hollow straight-through pipe inserted through the top of the airtight container. , the water level difference from the bottom of the intake pipe to the water level in the sealed container is the preset negative pressure water level difference threshold, and the sum of the pressure in the air duct and the threshold pressure corresponding to the negative pressure water level difference threshold is equal to atmospheric pressure. By applying the utility model, the water pressure for water supply to crops can be guaranteed to be kept constant.

Description

A negative pressure regulating system

technical field

The utility model relates to the agricultural underground irrigation technology, in particular to a negative pressure regulating system.

Background technique

During the growth and development of crops, the soil is often difficult to provide the necessary moisture for crops. Therefore, in the process of modern agricultural production, supplementing the corresponding moisture to the soil through irrigation is an important part of agricultural production and management activities.

Under the situation that the distribution of water resources in our country is extremely unbalanced, the use of negative pressure irrigation technology is an effective way to improve the efficiency of water resources utilization. Among them, the negative pressure irrigation technology is a technology that uses plastic pipes to transport water through the orifice on the capillary tube or the negative pressure irrigation head to the soil of the root system of the crops for local irrigation. The irrigator can evenly and slowly drip the water required by the crops into the root soil of the crops. Since the negative pressure irrigation does not destroy the soil structure, it can keep the water, fertilizer, air and heat inside the soil in a good condition suitable for the growth of crops; at the same time, the evaporation loss is small, no ground runoff is generated, the amount of irrigation water is small, and the duration of one irrigation is longer , the utilization rate of water resources is high; moreover, negative pressure irrigation does not require artificial pressure, and the negative pressure (water potential difference) generated by crop water consumption is used as the active pressure for crop water absorption, so the amount of irrigation water can be controlled more accurately, which can reduce Ineffective evaporation between trees will not cause water waste. Therefore, it is a water-saving irrigation method widely used in water-scarce areas, and can be applied to crops such as fruit trees, grain, vegetables, cash crops, and greenhouse irrigation.

Fig. 1 is a structural schematic diagram of a negative pressure irrigation water system in the prior art. Referring to Fig. 1, the negative pressure irrigation water system includes: an irrigation head 11, a water reservoir 12 and a negative pressure regulating device 13, wherein,

The negative pressure regulating device 13 includes: a U-shaped pipe 21 and a negative pressure regulating pipe 22, wherein one end of the negative pressure regulating pipe 22 communicates and extends into the left pipe of the U-shaped pipe 21, and the other end communicates and extends into the right side of the U-shaped pipe 21. inside the side tube;

The water reservoir 12 used to store water is a sealed container, and a negative pressure chamber is formed between the top of the water surface and the top of the water reservoir. The right side tube of the U-shaped tube communicates with the atmosphere, and the liquid level in the left side tube of the U-shaped tube 21 is the highest not higher than the position where the negative pressure regulating tube 22 stretches into the left side tube of the U-shaped tube 21;

The irrigation head 11 is connected to the bottom of the water storage device 12, and placed in the soil where the root system of crops grows;

The negative pressure chamber is filled with air at a preset pressure, so that the water potential of the irrigation head is higher than the soil water potential corresponding to the growth of crops, and smaller than the soil water potential when the soil is at the field water capacity;

The sum of the preset pressure and the pressure generated by the height difference of the liquid filled in the U-shaped tube 21 is equal to the atmospheric pressure.

In this negative pressure irrigation water system, the negative pressure chamber is connected with the left pipe. In the initial state, the water storage is filled with water, and the sum of the pressure in the negative pressure chamber and the pressure generated by the height difference of the liquid filled in the U-shaped pipe is equal to atmospheric pressure.

With the gradual increase of irrigation time, the water level in the water storage tank decreases, the space in the negative pressure chamber increases, and the pressure decreases. The sum of the pressure in the pressure chamber and the pressure generated by the height difference of the liquid filled in the U-shaped tube is equal to the atmospheric pressure.

When the liquid level in the right side tube drops below the lower edge of the position where the negative pressure regulating tube extends into the right side tube of the U-shaped tube, as the water level in the water storage device continues to drop, the pressure in the negative pressure chamber further decreases, due to The liquid in the negative pressure regulating tube is separated by the atmosphere, and the liquid height difference remains constant. If the sum of the pressure in the negative pressure chamber and the pressure generated by the liquid height difference in the negative pressure regulating tube is less than the atmospheric pressure, then, driven by the atmospheric pressure, the negative pressure The liquid in the regulating pipe rises along the negative pressure regulating pipe, and injects into the left pipe through the pipe head extending into the left pipe of the U-shaped pipe.

After the liquid in the negative pressure regulating pipe is all injected into the left pipe, because the liquid level in the left pipe is the highest not higher than the position stretched into the left pipe of the U-shaped pipe. Therefore, the negative pressure chamber, the space above the liquid surface of the left pipe, and the negative pressure regulating pipe are connected with the atmosphere, and the atmosphere enters the negative pressure chamber through the negative pressure regulating pipe and the space above the liquid surface of the left pipe, so that the pressure in the negative pressure chamber increases. The increased pressure can not only drive the water in the water reservoir to enter the soil through the fertilization head, but also drive the liquid level in the left pipe to drop, so that the liquid level in the right pipe rises until the liquid level in the right pipe rises above The second communication hole cuts off the passage of the atmosphere into the negative pressure chamber, and makes the liquid level of the left tube, the liquid level of the negative pressure regulating tube and the liquid level of the right tube reach a new dynamic balance, and so on.

However, in this negative pressure irrigation water system, the water pressure of the irrigation head is the sum of the pressure in the negative pressure chamber and the height of the liquid level in the water storage, and this sum value is the pressure of the irrigation head to supply water to the roots of the crops. However, due to the pressure in the negative pressure chamber The height of the liquid level in the pressure and negative pressure regulating tube is related to the height difference of the liquid level in the U-shaped tube, and fluctuates with the fluctuation of the height difference. Therefore, the pressure of the irrigation head to supply water to the crop roots fluctuates within a certain range and cannot be maintained. The constant water pressure cannot guarantee that crops will always grow under stable soil moisture conditions.

Utility model content

In view of this, the main purpose of this utility model is to propose a negative pressure adjustment system to ensure that the water pressure supplied to the crops remains constant, so that the crops can grow under stable soil moisture conditions, thereby realizing accurate control of the soil moisture content in the root zone. control.

In order to achieve the above purpose, the utility model provides a negative pressure regulating system, including: a negative pressure irrigation seepage device, an aqueduct, a liquid storage device, an air guide tube and a negative pressure regulator, wherein,

One end of the water guide pipe is connected to the negative pressure irrigation seepage device, and the other end is connected to the liquid reservoir through the liquid guide hole opened at the lower part of the side wall of the liquid reservoir;

The negative pressure irrigation infiltrator is placed obliquely, and the distance between the end connected with the water guide pipe and the ground surface is smaller than the distance between the other end and the ground surface;

Water is contained in the liquid reservoir;

One end of the air guide tube is connected to the liquid reservoir through the air guide hole opened on the lower part of the side wall of the liquid reservoir. The air guide hole and the liquid guide hole are located at the same horizontal position. The adjustment hole is connected to the negative pressure regulator;

The negative pressure regulator is composed of a sealed container and an air inlet pipe. The other end of the air guide pipe is connected to the airtight container through the gas adjustment hole on the upper part of the side wall of the airtight container. The air inlet pipe is a hollow straight-through pipe, which is inserted into the In the sealed container, there is water in the sealed container, the water level difference from the bottom of the intake pipe to the water level in the sealed container is the preset negative pressure water level difference threshold, and the pressure in the air duct is equal to the threshold pressure corresponding to the negative pressure water level difference threshold. and is equal to atmospheric pressure.

Preferably, the negative pressure irrigation infiltrator is placed in the root soil area of crops.

Preferably, the place where the water guide pipe is connected with the negative pressure irrigation infiltrator and the liquid reservoir, the place where the air guide pipe is connected with the liquid reservoir and the sealed container, the water inlet of the liquid reservoir and the air inlet pipe are inserted To the airtight container place, all utilize sealing ring to seal.

Preferably, the negative pressure irrigation infiltrator is a water-permeable and air-tight clay pipe.

Preferably, the obliquely placed negative pressure irrigation infiltrator has an included angle of 1-5° with the soil level, and the distance from one end of the clay pipe connected to the aqueduct to the ground surface is smaller than the distance from the other end to the ground surface.

Preferably, the water level in the sealed container is lower than the gas regulating hole.

Preferably, both the liquid reservoir and the sealed container are cylindrical containers.

Preferably, it further includes a water level gauge provided with a scale indicating water consumption, the water level gauge is externally connected to the liquid reservoir, and one end of the water level gauge is connected to the liquid reservoir through the first water level hole opened on the upper part of the side wall of the liquid reservoir, and the water level gauge The other end of the water tank is connected into the liquid storage through the first water level hole opened in the lower part of the side wall of the liquid storage, wherein the first water level hole is parallel to or higher than the liquid guide hole.

Preferably, the water level meter is in the shape of [.

Preferably, the air intake pipe is provided with a height scale from the bottom end upwards.

It can be seen from the above technical solutions that the utility model provides a negative pressure regulating system. Including: negative pressure irrigation infiltrator, water guide pipe, liquid reservoir, air guide pipe and negative pressure regulator, wherein, one end of the water guide pipe is connected to the negative pressure irrigation infiltrator, and the other end passes through the lower part of the side wall of the liquid reservoir The opened liquid guide hole is connected to the liquid reservoir; the negative pressure irrigation seepage device is placed obliquely, and the distance between the end connected with the water guide pipe and the ground surface is smaller than the distance between the other end and the ground surface; water is contained in the liquid reservoir; One end of the air guide tube is connected to the liquid reservoir through the air guide hole opened on the lower part of the side wall of the liquid reservoir. The air guide hole and the liquid guide hole are located at the same horizontal position. The adjustment hole is connected to the negative pressure regulator, and the air in the air guide tube is filled to the position connected with the air guide hole opened on the lower part of the side wall of the liquid reservoir; the negative pressure regulator is composed of a sealed container and an air intake tube, and the air guide tube The other end of the airtight container is connected to the airtight container through the gas regulating hole on the upper part of the side wall of the airtight container. The air inlet pipe is a hollow straight-through pipe, which is inserted into the airtight container through the top of the airtight container. Water is placed in the airtight container. The water level difference of the water level in the container is the preset negative pressure water level difference threshold, and the sum of the pressure in the air duct and the threshold pressure corresponding to the negative pressure water level difference threshold is equal to the atmospheric pressure. In this way, a constant negative pressure water head difference threshold value is produced by utilizing the air inlet pipe and a sealed container containing water, so that a constant water pressure can be provided to the negative pressure irrigation infiltrator (the difference between the pressure produced by the atmospheric pressure and the negative pressure water head difference threshold value) Poor), so as to ensure that crops have been growing under stable soil moisture conditions.

Description of drawings

Fig. 1 is a structural schematic diagram of a negative pressure irrigation water system in the prior art.

Fig. 2 is a schematic structural diagram of the negative pressure regulating system of the embodiment of the utility model.

Fig. 3 is a schematic diagram of the initial state of the negative pressure regulating system of the embodiment of the present invention.

Fig. 4 is a schematic diagram of the negative pressure regulating system of the embodiment of the present invention after it operates in the initial state.

detailed description

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Fig. 2 is a schematic structural diagram of the negative pressure regulating system of the embodiment of the utility model. Referring to Fig. 2, the negative pressure regulating system includes: a negative pressure irrigation infiltrator 201, a water conduit 202, a liquid reservoir 203, an air conduit 204 and a negative pressure regulator 205, wherein,

One end of the water guide pipe 202 is connected to the negative pressure irrigation infiltrator 201, and the other end is connected to the liquid reservoir 203 through the liquid guide hole 101 opened at the lower part of the side wall of the reservoir;

The negative pressure irrigation infiltrator 201 is placed obliquely, and the distance from the ground surface at one end connected with the water guide pipe 202 is smaller than the distance from the ground surface at the other end;

Water is contained in the liquid reservoir 203, and as an optional embodiment, a water inlet 102 is arranged on the top;

One end of the air guide tube 204 is connected to the liquid reservoir 203 through the air guide hole 103 opened at the lower part of the side wall of the liquid reservoir 203. The air guide hole 103 and the liquid guide hole 101 are located at the same horizontal position, and the other end of the air guide tube 204 is adjusted by negative pressure. The gas regulating hole 104 opened on the upper part of the side wall of the device 205 is connected to the negative pressure regulator 205;

The negative pressure regulator 205 is composed of a sealed container 105 and an air inlet pipe 106. The other end of the air guide pipe 204 is connected to the airtight container 105 through the gas regulating hole 104 provided on the upper part of the side wall of the airtight container 105. The air inlet pipe 106 is a hollow straight-through The pipeline is inserted into the sealed container 105 through the top of the sealed container 105. Water is placed in the sealed container 105. The water level difference from the bottom of the air inlet pipe 106 to the water level in the sealed container is the preset negative pressure water level difference threshold. The sum of the pressure and the threshold pressure corresponding to the negative pressure water level difference threshold is equal to the atmospheric pressure.

In the embodiment of the present invention, as an optional embodiment, the water level in the sealed container 105 is lower than the gas regulating hole 104, and the negative pressure water level difference threshold is set to h. As an optional embodiment, the negative pressure irrigation infiltrator is placed in the root soil area of the crops.

In the embodiment of the present invention, when the system works stably, as an optional embodiment, the air in the air duct 204 is filled to the position where it communicates with the air guide hole 103 opened at the lower part of the side wall of the liquid reservoir 203 .

At the connection between the liquid reservoir and the air duct, the side corresponding to the air duct is air, and the side corresponding to the liquid accumulator is water, that is, there is an air-liquid interface at the connection between the liquid accumulator and the air duct.

In the embodiment of the present utility model, at the places where the aqueducts are respectively connected with the negative pressure irrigation liquid infiltrator and the liquid storage device, the places where the air guide pipe is respectively connected with the liquid storage device and the sealed container, the water inlet of the liquid storage device and the The air intake pipe is inserted into the airtight container, and is sealed with a sealing ring.

In the embodiment of the utility model, the soil water potential is a natural property of the soil, that is, in most natural cases, the movement of soil nutrients in the soil depends on the soil moisture as the medium, and the water always flows from the place with high potential energy to the potential energy. low place. Therefore, whether water can flow to the root system of crops and whether the crops can absorb water depends entirely on the water potential difference between the soil water potential and the water potential of the crops. Through irrigation, the soil water potential can be improved. The soil water potential can achieve precise control of different soil moisture content to meet the needs of different growth periods of crops, and in a certain period of time, it can ensure that crops have been growing under stable soil moisture conditions.

It should be noted that the negative pressure described later in the embodiment of the utility model is relative to the atmospheric pressure, that is, the relative value of the pressure in the system and the atmospheric pressure. Since the water supply head of the system is smaller than the atmospheric pressure, it is also It is called negative pressure irrigation.

In the embodiment of the utility model, as an optional embodiment, the negative pressure irrigation seepage device is a water-permeable and air-tight clay pipe.

In the embodiment of the utility model, as an optional embodiment, the inner diameter of the clay pipe is 11 mm, the outer diameter is 18 mm, and the length is 250 mm.

In the embodiment of the utility model, the clay pipe is a dense porous structure, which is airtight under a certain pressure, but the moisture can seep out to the external soil by virtue of the water potential difference. Specifically, when using water supply negative pressure to supply water, the gap of the clay pipe is filled with water, and the water potential with the outer wall of the clay pipe (the contact between the clay pipe and the soil) is less than or equal to the water potential in the clay pipe (water supply negative pressure), so , during the water supply process of the system, the water in the reservoir can only flow to the soil, or keep the dynamic balance and not flow out, so that the water will always fill the gap of the clay pipe, which greatly restricts the air from entering the clay pipe, so that the clay pipe has no Breathable, but water-permeable properties.

In the embodiment of the present invention, the pottery clay pipe is embedded in the soil to a certain depth according to the distribution of crop roots and the water demand. For example, if the crop is cucumber, the suitable burial depth of the pottery clay pipe is 15-25cm (distance from the ground surface).

In the embodiment of the utility model, in order to facilitate the air bubbles generated in irrigation to discharge from the clay pipe to enter the liquid reservoir, the clay pipe placed obliquely and the soil level is at an angle of 1-5°, and is connected to the aqueduct. One end of the clay pipe is higher than the other end, that is, the distance between one end of the clay pipe connected with the aqueduct and the ground surface is smaller than the distance between the other end and the ground surface.

In the embodiment of the utility model, as an optional embodiment, in order to prevent the negative pressure regulation system from starting to operate, when the liquid reservoir is filled with water, the water in the liquid reservoir may enter along the air guide tube (CE tube) The negative pressure regulator affects the adjustment accuracy of the negative pressure regulator. In the embodiment of the present invention, the height of the E position of the air duct (the position connected with the sealed container) is higher than the height of the liquid reservoir, i.e. The position of the gas regulating hole is higher than the water level in the liquid reservoir. Preferably, the position of the gas regulating hole is higher than the water inlet of the liquid reservoir.

In the embodiment of the utility model, the water storage capacity in the liquid storage device can be filled with the required water volume at each stage according to the water demand of the crops at each stage.

In the embodiment of the utility model, as another optional embodiment, water is poured into the negative pressure regulator, and the water level is lower than the situation at the E (gas adjustment hole) position where the air guide tube communicates with the negative pressure regulator. Prevent the temperature difference between day and night from affecting the pressure controlled by the negative pressure regulator, improve the water control accuracy of negative pressure irrigation, set the anhydrous space in the negative pressure regulator as small as possible, that is, set the water level in the negative pressure regulator as close as possible to the E position , that is, the water level in the airtight container is slightly lower than the lower edge of the E position where the airway tube communicates with the airtight container (gas regulating hole).

In the embodiment of the utility model, as an optional embodiment, both the liquid storage device and the sealed container are cylindrical containers.

Preferably, the negative pressure regulating system further includes a water level gauge 206 provided with a scale indicating water consumption, the water level gauge 206 is externally connected to the liquid reservoir, and one end of the water level gauge 206 passes through the first water level hole opened on the upper part of the side wall of the liquid reservoir The other end of the water level gauge 206 is connected into the liquid reservoir through the first water level hole provided at the lower part of the side wall of the liquid reservoir. Wherein, the first water level hole is parallel to or higher than the liquid guide hole.

In the embodiment of the present utility model, as an optional embodiment, the water level gauge is in the shape of [, which is used to measure the change of the water level in the liquid storage device, and the water consumption is obtained according to the bottom area of the liquid storage device and the change of the water level, which is shown by the scale out. As another optional embodiment, the water level gauge is a transparent graduated tube.

As an optional embodiment, the aperture of the water conduit is greater than 5 cm.

In the embodiment of the utility model, the air intake pipe communicates with the outside air. As an optional embodiment, the air intake pipe is provided with a height scale from the bottom end upwards.

In the embodiment of the utility model, the gas pressure in the space above the water surface in the sealed container is less than or equal to the atmospheric pressure. By changing the height of the inlet pipe inserted into the water surface in the sealed container, the gas pressure (air pressure) in the space above the water liquid surface in the sealed container can be controlled, and then the soil water potential in a certain range of soil can be controlled by supplying water to the soil through the system. So that the soil water potential is consistent with the system water supply head set by the intake pipe, and the soil water potential is related to the soil moisture content. Therefore, by maintaining the soil water potential at a certain value, that is, by adjusting the height of h, the precise control of soil moisture can be achieved , and then provide the optimum soil moisture content in different growth stages of crops. The soil water potential is the negative water pressure (water supply head) provided by the system. The CE segment pipeline where the trachea is located is filled with air. Therefore, the pressures at position A in the inner chamber of the negative pressure irrigation infiltrator, at position B of the aqueduct, and at positions C and E of the air duct are all equal. The sum of the pressure at position E (negative water pressure of water supply) and the water level difference from the air-water isolation liquid level of the intake pipe to the water level in the sealed container is atmospheric pressure. Therefore, by controlling the height of the air inlet pipe inserted into the water surface in the sealed container, the negative water pressure of the water supply can be controlled, so that the soil moisture content can be kept at different levels.

The working process of the negative pressure regulating system of the embodiment of the utility model is described below:

After the negative pressure regulating system of the embodiment of the present utility model is installed, FIG. 3 is a schematic diagram of the initial state of the negative pressure regulating system of the embodiment of the present utility model. Referring to Fig. 3, the liquid reservoir is filled with water through the water inlet, and the water inlet is sealed, and the sealed container is filled with the amount of water close to the position where the air guide tube is connected to the sealed container (gas adjustment hole), and the air inlet pipe is inserted into the sealed container, The distance between the bottom end of the intake pipe and the water level in the airtight container is the first height, the water level in the air intake pipe is level with the water level in the airtight container, the air pressure in the air duct is atmospheric pressure, and the air in the air duct is not It is filled to the position where it communicates with the air guide hole opened on the lower part of the side wall of the liquid reservoir;

During the initial operation of the negative pressure regulating system, the air pressure in the air guide pipe is atmospheric pressure, and the pressure of the outlet of the water guide pipe is also atmospheric pressure, which is higher than the soil water potential, driving the water in the liquid reservoir to pass through the water guide pipe and the negative pressure irrigation seepage device Infiltrate into the soil, causing the water level in the reservoir to drop, and a space appears above the reservoir, thereby driving the air in the space above the water surface of the sealed container to enter the space above the reservoir through the air guide tube, and the water level in the air guide tube is aligned with the reservoir The position where the air guide hole opened at the lower part of the side wall is connected is close;

Fig. 4 is a schematic diagram of the negative pressure regulating system of the embodiment of the present invention after it operates in the initial state. Referring to Figure 4, after the air in the space above the liquid level of the sealed container enters the space above the liquid reservoir through the air guide tube, the air pressure in the air guide tube drops, and the atmosphere in the intake tube drives the water level in the intake tube to drop to match the water level in the sealed container. The liquid level produces a water level difference, so that the sum of the pressure generated by the air pressure in the air duct and the water level difference is equal to the atmospheric pressure. As the water in the reservoir enters the crop root soil through the aqueduct and the negative pressure irrigation infiltrator, the soil moisture gradually increases. High, the corresponding soil water potential gradually increases, and the air pressure in the air duct gradually decreases;

The air pressure in the air duct drops, but it is still higher than the soil water potential, so that the water level in the liquid reservoir continues to drop, and the air in the space above the liquid level in the sealed container is continuously driven to enter the space above the liquid reservoir through the air duct, thereby making the air in the air duct Filled to the position connected with the air guide hole opened on the lower part of the side wall of the liquid reservoir, the atmosphere in the intake pipe drives the water level in the intake pipe to continue to drop until the water level in the intake pipe drops to the bottom of the intake pipe, When the water level difference between the water level in the trachea and the water level in the sealed container reaches the first height, the pressure in the space above the sealed container of the negative pressure regulator becomes a constant value, that is, the water supply head of the system is a constant value at this time, because The soil water content of the root soil of crops supplied by the system increases, and when it reaches a certain value, the soil water potential corresponding to the soil water content is consistent with the water supply head of the system, and then a dynamic balance is reached, and the liquid reservoir stops supplying water to the soil, and the negative The pressure regulating system enters a stable operating state, as shown in Figure 2;

During the stable operation of the negative pressure regulation system, due to the evaporation or transpiration of the crops, the water content of the soil around the root system will decrease again. The water level in the liquid tank drops, the negative pressure of the system water supply drops, and the air pressure in the air duct is stronger than the negative pressure of the system water supply, thus driving the air in the sealed container to enter the space above the liquid storage along the air duct to maintain the B position in the liquid storage Balance with the pressure at position C, thus completing a cycle process. In this way, when the negative pressure of the system water supply changes at the beginning, the intake pipe can be driven to suck air from the outside into the sealed container, thereby maintaining the constant negative pressure of the system water supply and ensuring that the crops are always growing in stable soil moisture (constant soil moisture content) rate) conditions, to achieve continuous, automatic and stable control of crops on water.

In the embodiment of the utility model, because the air pressure in the air duct is always greater than or equal to the soil water potential corresponding to the soil water content, the air can only enter the space above the liquid storage from the air duct, that is, the space above the liquid storage is always in the space above the air duct. The state of inhalation.

In the embodiment of the utility model, the system can provide suitable water level by adjusting the water level difference between the position of the bottom end of the intake pipe in the negative pressure regulator and the position of the water level in the sealed container according to the law of water demand of crops in different stages. Water supply.

In the embodiment of the utility model, if the system is not irrigating, there is water of a certain water level in the air inlet pipe, and the water level in the water inlet pipe is equal to the water level in the sealed container. The pressure generated by the air pressure and the height difference in the air duct is equal to the atmospheric pressure. It is necessary to increase the height difference so that the sum of the air pressure and the water level difference in the air duct is equal to the atmospheric pressure. Since the diameter of the water inlet pipe is small, the diameter of the sealed container is large , so that the water with water level in the air intake pipe is quickly emptied, and the water discharged into the airtight container has a negligible effect on the water level in the airtight container, so that the air pressure in the air duct quickly forms a constant pressure.

In the embodiment of the utility model, as an optional embodiment, if the soil moisture content of the cultivated crops is lower, the time required to form a constant pressure state is also shorter, so that the air pressure in the air duct can be reduced during the irrigation process. Adaptive adjustment, no manual or mechanical adjustment of the air pressure in the air duct is required.

Therefore, the utility model embodiment has the following advantages:

(1), energy saving;

The embodiment of the utility model does not need an external pressurized power device, and realizes the continuous and automatic acquisition of water by the crops by utilizing the physiological characteristics of the crops and the soil tension characteristics, and ensures that the water pressure supplied to the crops remains constant, so that the crops grow in a stable environment. under soil moisture conditions.

(2) It is suitable for irrigation of different crops and different growth periods of crops;

The embodiment of the utility model can irrigate according to the water demand of the crops in different periods. For the situation that the suitable soil water content of the crops in different growth periods is different, the water supply load of the system can be adjusted by changing the height difference between the air intake pipe and the liquid level in the sealed container. Pressure, timely and appropriate water supply for crops in different growth periods.

(3) Avoid blockage during irrigation.

In the embodiment of the utility model, the water-permeable and air-tight clay pipe is used for the negative pressure irrigation infiltrator, which can greatly improve the blockage of the emitter by soil particles.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the protection scope of the present utility model. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (10)

1. A negative pressure regulating system, characterized in that, the negative pressure regulating system comprises: a negative pressure irrigation seepage device, an aqueduct, a liquid reservoir, an air guide tube and a negative pressure regulator, wherein, One end of the water guide pipe is connected to the negative pressure irrigation seepage device, and the other end is connected to the liquid reservoir through the liquid guide hole opened at the lower part of the side wall of the liquid reservoir; The negative pressure irrigation infiltrator is placed obliquely, and the distance between the end connected with the water guide pipe and the ground surface is smaller than the distance between the other end and the ground surface; Water is contained in the liquid reservoir; One end of the air guide tube is connected to the liquid reservoir through the air guide hole opened on the lower part of the side wall of the liquid reservoir. The air guide hole and the liquid guide hole are located at the same horizontal position. The adjustment hole is connected to the negative pressure regulator; The negative pressure regulator is composed of a sealed container and an air inlet pipe. The other end of the air guide pipe is connected to the airtight container through the gas adjustment hole on the upper part of the side wall of the airtight container. The air inlet pipe is a hollow straight-through pipe, which is inserted into the In the sealed container, there is water in the sealed container, the water level difference from the bottom of the intake pipe to the water level in the sealed container is the preset negative pressure water level difference threshold, and the pressure in the air duct is equal to the threshold pressure corresponding to the negative pressure water level difference threshold. and is equal to atmospheric pressure. 2. The negative pressure regulating system according to claim 1, characterized in that, the negative pressure irrigation infiltrator is arranged in the root soil area of crops. 3. Negative pressure regulating system as claimed in claim 1, it is characterized in that, at the place where the aqueduct is respectively connected with the negative pressure irrigation infiltrator and the liquid reservoir, the air guide pipe is respectively connected with the liquid reservoir and the sealed container The passage, the water inlet of the liquid reservoir and the air inlet pipe inserted into the sealed container are all sealed with a sealing ring. 4. The negative pressure regulating system according to claim 1, characterized in that, the negative pressure irrigation infiltrator is a water-permeable and air-tight clay pipe. 5. The negative pressure regulating system as claimed in claim 4, characterized in that, said obliquely placed negative pressure irrigation infiltrator is at an angle of 1-5° with the soil level, and the clay pipe connected with the aqueduct The distance from one end to the ground surface is smaller than the distance from the other end to the ground surface. 6. The negative pressure regulating system according to claim 1, wherein the water level in the sealed container is lower than the gas regulating hole. 7. The negative pressure regulating system according to claim 1, characterized in that, both the liquid reservoir and the sealed container are cylindrical containers. 8. The negative pressure regulating system according to claim 1, further comprising a water level gauge provided with a scale indicating water consumption, the water level gauge is externally connected to the liquid reservoir, and one end of the water level gauge is opened through the upper part of the side wall of the liquid reservoir The first water level hole of the water level gauge is connected to the liquid reservoir, and the other end of the water level gauge is connected to the liquid reservoir through the first water level hole opened at the lower part of the side wall of the liquid reservoir, wherein the first water level hole is parallel to or higher than the liquid guide hole . 9. The negative pressure regulating system according to claim 1, wherein the water level gauge is in the shape of [. 10. The negative pressure regulating system according to claim 1, characterized in that, the air inlet pipe is provided with a height scale from the bottom to the top.