Dynamic circulating valve capable of automatically adjusting jet flow

Abstract

The utility model discloses an automatic jet flow adjusting dynamic circulating valve which comprises a valve body. The nozzle is provided with a spraying hole; the spraying needle movably penetrates through the spraying hole in the axis direction of the nozzle, and the spraying needle comprises a needle head section which is sleeved with an adjusting spring; the needle tail section comprises a forward conical section, and the diameter of the forward conical section is gradually increased from the needle head section to the needle tail section; when the fluid pressure of the main water inlet is increased, the high-pressure fluid compresses the adjusting spring and pushes the spray needle to move towards the mixed water outlet, the gap between the positive conical section and the inner wall of the spray hole is increased, negative pressure formed at the communicating water inlet is accelerated, and negative pressure injection is strengthened; when the fluid pressure of the main water inlet is reduced, the adjusting spring rebounds to drive the spray needle to move towards the main water inlet, the gap between the forward conical section of the needle tail and the inner wall of the spray hole is reduced, and negative pressure injection is weakened. The adjusting spring is arranged on the spray needle, and automatic adjustment can be achieved according to the fluid pressure of the main water inlet.

Description

TECHNICAL FIELD

[0001] The utility model relates to water mixing valve technical field, more specifically, the utility model relates to a kind of automatic regulating jet dynamic circulation valve. BACKGROUND

[0002] For building water supply and drainage system, pressure balance is crucial, usually adopts jet device (such as jet valve including nozzle, spray needle and the like structure) to carry out water pressure regulation, but existing jet valve faces different floor water situation change, relies on fixed aperture design, needs to manually adjust the position of spray needle to adapt to pressure fluctuation, cannot automatically regulate to maintain stable water pressure, if not timely adjustment, low floor user under long-term use, water flow may be too fast due to water pressure being too high, pipe is prone to damage and the like, high floor user under long-term use, water supply difficulty may be faced due to water pressure being insufficient, seriously affect user experience, and it is not conducive to long-term stable operation of building water supply and drainage system.Therefore, there is an urgent practical need to develop a kind of jet valve capable of automatic regulation to realize efficient, energy-saving, stable fluid management. SUMMARY

[0003] One object of the utility model is to provide a kind of automatic regulating jet dynamic circulation valve, comprising:

[0004] valve body, main inlet, communication inlet and mixed outlet are equipped on it;

[0005] nozzle, it is located in valve body, nozzle includes coaxially arranged first flow channel, second flow channel and contraction section flow channel, first flow channel is communicated with main inlet, second flow channel is communicated with communication inlet, the end of contraction section flow channel is communicated with mixed outlet, the inner wall of second flow channel is circumferentially provided with annular limit block, and the center of annular limit block is provided with spray hole;

[0006] spray needle, it is movably worn on spray hole along the axis direction of nozzle, and spray needle includes:

[0007] needle head section, one end of needle head section extends first flow channel, adjusting spring is sleeved on needle head section, one end of adjusting spring is fixed on spring seat located at the end of needle head section, and the other end is fixed on nozzle;

[0008] needle tail section, it is located in second flow channel, and it includes positive taper section, and the diameter of positive taper section gradually expands from needle head section to needle tail section;

[0009] when the fluid pressure of main inlet increases, high-pressure fluid compresses adjusting spring, and drives spray needle to move to the direction of mixed outlet, the gap between positive taper section and the inner wall of spray hole increases, and the negative pressure formed at communication inlet is accelerated, and the negative pressure suction is strengthened;

[0010] When the fluid pressure of the main water inlet decreases, the adjusting spring rebounds to drive the spray needle to move towards the main water inlet, the gap between the positive taper section of the needle tail and the inner wall of the spray hole decreases, and the negative pressure injection weakens.

[0011] Preferably, the stiffness coefficient of the adjusting spring and the rated pressure range of the fluid of the main water inlet satisfy: k=(0.15~0.3)P max ×A / Δx, wherein k is the spring stiffness coefficient (N / mm), P max is the maximum pump starting pressure of the main water inlet (MPa), Δx is the maximum stroke displacement amount of the spray needle (mm), and A is the pressure receiving area of the needle head section (mm²).

[0012] Preferably, the pre-tightening force F0 of the adjusting spring and the minimum pump starting pressure and the maximum pump starting pressure of the main water inlet satisfy: F0=0.12 P max ×A+0.3 P min ×A, wherein A is the pressure receiving area of the needle head section (mm²), P min is the minimum pump starting pressure, and P max is the maximum pump starting pressure.

[0013] Preferably, the spring seat is threadedly connected with the end of the needle head section, and a pressure receiving surface perpendicular to the axis of the spray needle is arranged on the spring seat, and the pressure receiving surface constitutes the pressure receiving area of the needle head section.

[0014] Preferably, the needle head section comprises a spray needle body and a plurality of convex rib sections uniformly distributed along the circumference of the spray needle body and arranged in the axial direction of the spray needle body, and the plurality of convex rib sections form fluid passages therebetween.

[0015] Preferably, the convex rib section comprises a first convex rib part and a second convex rib part, the first convex rib part is opposite to the communication between the second flow channel and the communication water inlet, and the radial dimension of the first convex rib part is smaller than the radial dimension of the second convex rib part, so as to form a fluid passage with the inner cavity wall of the second flow channel.

[0016] The inner cavity wall of the nozzle is formed with a slot corresponding to the second convex rib part, and the second convex rib part is slidably arranged on the slot in the axial direction of the nozzle.

[0017] Preferably, the contraction section flow channel comprises a mixing section and a diffusion section arranged in sequence from the water inlet end to the water outlet end, the diffusion section is in a tapered expansion structure, the mixing section and the diffusion section are connected through a tapered connecting section, the curvature radius R of the connecting section and the diameter D of the mixing section satisfy R=0.3D~0.6D, and the ratio d2 / d1 of the outlet diameter d2 of the diffusion section to the inlet diameter d1 of the mixing section satisfies d2 / d1=1.2~1.8.

[0018] Preferably, the end of the needle tail section is provided with a reverse taper section, the diameter of the reverse taper section gradually expands from the end close to the injection hole to the end far away, and forms a converging annular flow with the inner wall of the second flow channel, the ratio of the outlet cross-sectional area to the inlet cross-sectional area of the converging annular flow channel is 1:1.5-2.5.

[0019] Preferably, the taper angle α of the reverse taper section is 10-25°, the reverse taper section extends to form a guide boss at the end, the outer diameter of the guide boss is 0.5-1.2 mm larger than the minimum gap of the inner wall of the second flow channel, and the ratio L / d3 of the length L of the converging annular flow channel to the inlet diameter d3 is 0.8-1.2.

[0020] Preferably, the valve body is provided with a branch water outlet at the upstream end of the first fluid;

[0021] It also includes a branch pipe, which is in communication with the branch water outlet and the communication water inlet at both ends.

[0022] The utility model at least includes the following beneficial effects:

[0023] Firstly, the adjusting spring is arranged on the spray needle, and the spray needle can be automatically adjusted according to the fluid pressure of the main water inlet.

[0024] Secondly, the rigidity coefficient and the pre-tightening force of the adjusting spring are calculated and set, so that the spray needle can move accurately, the stability can be maintained under different working conditions, the change of the pressure of the main water inlet can be effectively adapted, and diversified use requirements can be met.

[0025] Thirdly, the mixing section and the diffusion section are connected through the transition of the connecting section with a specific curvature radius, and the ratio of the outlet diameter of the diffusion section to the inlet diameter of the mixing section is set, so that the fluid can be fully mixed, the vortex and turbulence of the fluid at the connection are reduced, the energy loss is reduced, and the energy utilization efficiency of the whole jet valve is improved.

[0026] Other advantages, objects and features of the utility model will be embodied partly through the following description, and will be understood by those skilled in the art through research and practice of the utility model. ACCURATE DESCRIPTION

[0027] Figure 1 It is a side sectional view of the automatic adjusting jet dynamic circulation valve in a high-pressure state according to one of the technical schemes of the utility model;

[0028] Figure 2 It is a side sectional view of the automatic adjusting jet dynamic circulation valve in a low-pressure state according to one of the technical schemes of the utility model;

[0029] Figure 3 It is an explosion view of the spray needle according to one of the technical schemes of the utility model;

[0030] Figure 4 Figure 1 is a side view of the nozzle structure according to one of the technical solutions of the present application;

[0031] Figure 5 Figure 2 is a side view of the needle structure according to one of the technical solutions of the present application.

[0032] In the drawings, the following notations are used:

[0033] 1, valve body; 2, main water inlet; 3, communication water inlet; 4, mixed water outlet; 5, branch water outlet; 6, nozzle; 7, needle; 8, mixed water section; 9, diffusion section; 10, adjusting spring; 11, spring seat; 12, forward cone section; 13, reverse cone section; 14, needle tail section; 15, first convex rib part; 16, second convex rib part; 17, convex rib section; 18, first flow channel; 19, second flow channel; 20, contraction section flow channel; 21, spray hole. DETAILED DESCRIPTION

[0034] The present application will be further described in detail below with reference to the drawings, so that those skilled in the art can implement the present application according to the description.

[0035] It should be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials can be obtained from commercial sources unless otherwise specified; in the description of the present application, the terms indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0036] As shown in Figures 1-5 The present application provides an automatic adjusting jet flow dynamic circulation valve, comprising:

[0037] A valve body 1 is provided with a main water inlet 2, a communication water inlet 3 and a mixed water outlet 4; specifically, the valve body 1 is the main structure of the automatic adjusting jet flow dynamic circulation valve, which is usually made of high-strength, corrosion-resistant metal material (such as stainless steel) to ensure its reliability and durability in different working environments, the main water inlet 2 is used for connecting high-pressure fluid, the communication water inlet 3 is used for connecting fluid to be injected, and the mixed water outlet 4 outputs the mixed fluid;

[0038] A nozzle 6 is arranged in the valve body 1, the nozzle 6 comprises coaxially arranged first flow channel 18, second flow channel 19 and convergent section flow channel 20, the first flow channel 18 is communicated with the main water inlet 2, the second flow channel 19 is communicated with the communicating water inlet 3, the end of the convergent section flow channel 20 is communicated with the mixed water outlet 4, the inner wall of the second flow channel 19 is circumferentially provided with an annular limiting block, and a spray hole 21 is arranged in the center of the annular limiting block; Specifically, the first flow channel 18 is used to guide the high-pressure fluid of the main water inlet 2 into the nozzle 6, the inner diameter and length of the first flow channel 18 are designed according to the flow and pressure of the main water inlet 2 to ensure that the fluid can flow smoothly, the second flow channel 19 is used to introduce the fluid that needs to be injected, the annular limiting block is arranged at the connection between the second flow channel 19 and the convergent section flow channel 20, the annular limiting block is used to limit the movement range of the spray needle 7 and provide support and guidance for the spray needle 7, and the convergent section flow channel 20 is used to mix the fluid flowing from the first flow channel 18 and the second flow channel 19 and accelerate the flow of the fluid, and the design of the convergent section flow channel 20 can improve the mixing effect and injection efficiency of the fluid;

[0039] The spray needle 7 is movably arranged on the spray hole 21 along the axial direction of the nozzle 6, and the spray needle 7 comprises:

[0040] The needle head section is arranged in the first flow channel 18, the adjusting spring 10 is sleeved on the needle head section, one end of the adjusting spring 10 is fixed on the spring seat 11 at the end of the needle head section, and the other end is fixed on the nozzle 6; Specifically, the spring seat 11 can be fixed on the end of the needle head section in a threaded connection manner, so that the installation and disassembly of the adjusting spring 10 are facilitated, and the adjusting spring 10 is used to drive the spray needle 7 to move in the spray hole 21 according to the change of the fluid pressure of the main water inlet 2;

[0041] The needle tail section 14 is arranged in the second flow channel 19, and comprises a positive taper section 12, and the diameter of the positive taper section 12 gradually expands from the needle head section to the needle tail section 14; Specifically, the gap between the positive taper section 12 and the inner wall of the spray hole 21 determines the strength of the negative pressure injection;

[0042] When the fluid pressure of the main water inlet 2 increases, the high-pressure fluid compresses the adjusting spring 10, pushes the spray needle 7 to move towards the mixed water outlet 4, the gap between the positive taper section 12 and the inner wall of the spray hole 21 increases, the flow rate of the fluid in the second flow channel 19 increases, thereby accelerating the negative pressure formed at the communicating water inlet 3, and strengthening the negative pressure injection;

[0043] When the fluid pressure of the main water inlet 2 decreases, the adjusting spring 10 rebounds and drives the spray needle 7 to move towards the main water inlet 2, the gap between the positive taper section 12 of the needle tail and the inner wall of the spray hole 21 decreases, the flow rate of the fluid in the second flow channel 19 decreases, thereby slowing down the negative pressure formed at the communicating water inlet 3, and weakening the negative pressure injection.

[0044] In the above technical scheme, when the fluid pressure of the main water inlet 2 is increased, the high-pressure fluid acts on the needle segment, the adjusting spring 10 is compressed, and the adjusting spring 10 is compressed. After being compressed, the injection needle 7 is pushed to move towards the mixed water outlet 4. With the movement of the injection needle 7, the gap between the forward taper segment 12 and the inner wall of the injection hole 21 increases. According to the principle of fluid mechanics, after the gap increases, the flow rate of the fluid increases, thereby forming a stronger negative pressure at the communication water inlet 3. The fluid at the communication water inlet 3 is injected into the nozzle 6, the negative pressure injection effect is strengthened, and more injected fluid is mixed with the high-pressure fluid in the contraction segment flow passage 20 of the main water inlet 2, and then output from the mixed water outlet 4. When the fluid pressure of the main water inlet 2 is reduced, the pressure acting on the needle segment decreases, the adjusting spring 10 rebounds under the action of the previously compressed force, the rebound of the adjusting spring 10 drives the injection needle 7 to move towards the main water inlet 2. At this time, the gap between the needle tail forward taper segment 12 and the inner wall of the injection hole 21 decreases, the flow rate of the fluid decreases after the gap decreases, the negative pressure at the communication water inlet 3 decreases, and the negative pressure injection effect also decreases. The flow of the injected fluid is correspondingly reduced. The function of automatically adjusting the negative pressure injection strength according to the fluid pressure of the main water inlet 2 of the utility model makes the jet valve adapt to different working pressure environments without frequent manual intervention, greatly improves the working efficiency, and reduces the labor cost.

[0045] In another technical scheme, the rigidity coefficient of the adjusting spring 10 and the fluid rated pressure range of the main water inlet 2 satisfy: k=(0.15~0.3)P max ×A / Δx, wherein k is the spring rigidity coefficient (N / mm), P max is the maximum pump starting pressure (MPa) of the main water inlet 2, Δx is the maximum stroke displacement amount (mm) of the injection needle 7, and A is the pressure receiving area (mm²) of the needle segment. Specifically, in the actual application scene of the jet valve, first, the maximum pump starting pressure of the main water inlet 2 can be measured by using a pressure sensor. In the system normal operation cycle, the pressure value of the main water inlet 2 is recorded each time the pump is started, and the maximum value is selected as P max , and corrected according to the actual situation. According to the design structure of the jet valve, the maximum stroke displacement amount Δx of the injection needle 7 is theoretically calculated and actually tested through geometric relationship and mechanical principle. Then, the specific value of A is determined according to the actual production. The rigidity coefficient of the adjusting spring 10 is calculated according to the above values. According to the calculated spring rigidity coefficient, a suitable adjusting spring 10 is selected, which can avoid the problem of inaccurate adjustment caused by the over-soft or over-hard adjusting spring 10, so that the adjusting process of the jet valve is more delicate, and the accuracy of the negative pressure injection strength adjustment is improved.

[0046] In another technical solution, the pre-tightening force F0 of the adjusting spring 10 and the minimum pump starting pressure and the maximum pump starting pressure of the main water inlet 2 satisfy: F0=0.12 P max ×A+0.3 P min ×A, wherein A is the pressure area (mm2) of the needle segment, P min is the minimum pump starting pressure, P max is the maximum pump starting pressure; specifically, in the system where the fluidic valve is actually applied, a pressure sensor is installed at the main water inlet 2, and multiple pump starting operations are performed on the system, and the pressure value of the main water inlet 2 at each pump starting is recorded, wherein the maximum value is P max , and the minimum value is P min . The adjusting spring 10 is selected according to the calculated pre-tightening force, which ensures that the adjusting spring 10 can provide sufficient initial force at the minimum pump starting pressure, so that the injection needle 7 is at a suitable initial position, ensuring that the fluidic valve can be started smoothly, avoiding the situation that the fluidic valve cannot work normally due to too low pressure. The formula also considers the influence of the maximum pump starting pressure, so that the adjusting spring 10 can maintain stable performance under high pressure. When the pressure of the main water inlet 2 reaches the maximum pump starting pressure, the pre-tightening force and the pressure change cooperate to ensure that the injection needle 7 can move according to the design requirements, maintain the normal working state of the fluidic valve, and prevent component damage or adjustment failure due to too high pressure.

[0047] In another technical solution, the spring seat 11 is threadedly connected with the end of the needle segment, and the spring seat 11 is provided with a pressure receiving surface perpendicular to the axis of the injection needle 7, and the pressure receiving surface constitutes the pressure area of the needle segment; specifically, one end of the adjusting spring 10 is fixed on the spring seat 11, and the fixing method can adopt welding or other reliable connection methods. The internal thread of the spring seat 11 is aligned with the external thread of the end of the needle segment, and is screwed in. During the screwing-in process, it is necessary to ensure that the axes of the two coincide to avoid deflection. The spring seat 11 and the needle segment are threadedly connected, which is convenient for disassembly, installation or replacement. The pressure receiving surface constitutes the pressure area of the needle segment, and its size is clear and easy to measure.

[0048] In another technical solution, the needle segment comprises a spray needle 7 body, a plurality of rib segments 17 evenly distributed along the circumference of the spray needle 7 body and arranged to extend in the axial direction of the spray needle 7 body, and the plurality of rib segments 17 form fluid channels between each other; specifically, in actual processing, the rib segments 17 can be formed by machining methods such as cutting methods, or the ribs can be integrally formed with the spray needle 7 body, made of corrosion-resistant materials, and the spray needle 7 with the rib segments 17 is inserted into the spray hole 21 along the axial direction of the nozzle 6, ensuring that the spray needle 7 can freely slide in the spray hole 21. During the insertion process, attention should be paid to the position of the rib segments 17 to avoid interference with the inner wall of the nozzle 6. The rib segments 17 help to improve the negative pressure suction effect at the communication inlet 3. More uniform and smooth fluid flow can make the fluid in the main inlet 2 more effectively form a negative pressure when passing through the nozzle 6, and the fluid in the communication inlet 3 is more quickly and stably sucked in.

[0049] In another technical solution, the rib segment 17 comprises a first rib portion 15 and a second rib portion 16, the first rib portion 15 is opposite to the communication of the second flow channel 19 and the communication inlet 3, and the radial dimension of the first rib portion 15 is smaller than the radial dimension of the second rib portion 16, so as to form a fluid channel with the inner cavity wall of the second flow channel 19; specifically, the length of the first rib portion 15 depends on the axial size of the water inlet of the nozzle 6, and is generally the length of the first flow channel 18 inlet in the axial direction of the spray needle 7 plus the stroke of the spray needle 7;

[0050] The inner cavity wall of the nozzle 6 is formed with a slot corresponding to the second rib portion 16, and the second rib portion 16 is arranged to slide on the slot in the axial direction of the nozzle 6; specifically, the slot corresponding to the second rib portion 16 formed on the inner cavity wall of the nozzle 6 provides accurate guidance for the movement of the spray needle 7. The size of the fluid channel formed by the first rib portion 15 and the inner cavity wall of the second flow channel 19, and the matching size of the second rib portion 16 and the slot of the inner cavity wall of the nozzle 6, ensure that the fluid can flow smoothly and the spray needle 7 can slide flexibly. The arrangement of the fluid channel enables the two fluids to intersect in a more suitable manner, increases the contact area and mixing time between the fluids, thereby improving the mixing uniformity and ensuring the quality of the mixed fluid output from the mixed outlet 4.

[0051] In another technical solution, the contraction section flow channel 20 includes a mixing section 8 and a diffusion section 9 arranged in sequence from the water inlet end to the water outlet end, the diffusion section 9 is in a tapered expansion structure, the mixing section 8 and the diffusion section 9 are connected through a tapered connecting section, the curvature radius R of the connecting section and the diameter D of the mixing section 8 satisfy R = 0.3D ~ 0.6D, and the ratio d2 / d1 of the outlet diameter d2 of the diffusion section 9 to the inlet diameter d1 of the mixing section 8 is 1.2 ~ 1.8; specifically, the smooth transition of the tapered connecting section reduces the local resistance loss of the fluid during flow, when the fluid enters the diffusion section 9 from the mixing section 8, if there is no suitable transition structure, vortex and turbulence will be formed at the connection, which will cause a large amount of energy loss. The reasonable curvature radius of the connecting section and the diameter ratio of the diffusion section 9 to the mixing section 8 can make the fluid change the flow direction and speed smoothly, reduce the energy loss, and improve the energy utilization efficiency of the entire jet valve.

[0052] In another technical solution, the needle tail section 14 is provided with a reverse taper section 13 at the end, the diameter of the reverse taper section 13 is tapered from the needle head section to the needle tail section 14, and forms a tapered annular flow with the inner wall of the second flow channel 19, the ratio of the outlet cross-sectional area to the inlet cross-sectional area of the tapered annular flow channel is 1:1.5 ~ 2.5; specifically, through processes such as numerical control turning or grinding, the diameter of the reverse taper section 13 is tapered from the needle head section to the needle tail section 14, and the taper is strictly controlled, according to the principle of fluid mechanics, when the fluid flows in the tapered flow channel, the flow rate will gradually increase, when the fluid of the main water inlet 2 pushes the jet needle 7 to move, the fluid in the second flow channel 19 accelerates in the tapered annular flow channel, thereby forming a stronger negative pressure at the communication water inlet 3, which can more effectively induce the fluid of the communication water inlet 3, improve the induction efficiency of the jet valve, so that more fluid can be introduced into the mixing process, and by controlling the ratio of the outlet cross-sectional area to the inlet cross-sectional area of the tapered annular flow channel within the range of 1:1.5 ~ 2.5, the acceleration degree of the fluid in the flow channel and the negative pressure size can be accurately adjusted.

[0053] In another technical solution, the taper angle α of the reverse taper section 13 is 10 ~ 25°, the reverse taper section 13 extends to form a guide boss at the end, the outer diameter of the guide boss and the minimum gap between the inner wall of the second flow channel 19 are 0.5 ~ 1.2 mm, and the ratio L / d3 of the length L of the tapered annular flow channel to the inlet diameter d3 is 0.8 ~ 1.2; specifically, when the fluid flows from the larger diameter end to the smaller diameter end, the taper angle determines the rate and direction of the increase of the flow rate of the fluid, a suitable taper angle can maximize the flow rate of the fluid while ensuring smooth flow of the fluid, a gap of 0.5 ~ 1.2 mm can ensure that the fluid can smoothly pass through the tapered annular flow channel, and can prevent the gap from being too large to cause negative pressure leakage and affect the induction effect, and the ratio of 0.8 ~ 1.2 can make the fluid have enough time and space to mix fully in the flow channel.

[0054] In another technical solution, the valve body 1 is provided with a branch water outlet 5 at the upstream end of the first fluid;

[0055] Further comprising a branch pipe, both ends of which are communicated with the branch water outlet 5 and the communicating water inlet 3 respectively; specifically, the connection mode of the branch pipe with the main water inlet 2 and the communicating water inlet 3 can be threaded connection, flange connection and welding connection, etc., the branch pipe introduces part of the fluid of the main water inlet 2 into the communicating water inlet 3 through the branch water outlet 5, thereby increasing the fluid energy at the communicating water inlet 3, when the fluid of the main water inlet 2 forms negative pressure through the nozzle 6 to induce the fluid of the communicating water inlet 3, the additional fluid transported by the branch pipe can enhance the induction effect, so that more fluid is induced into the fluidic valve, thereby improving the induction efficiency.

[0056] Although the embodiments of the present application have been disclosed as above, it is not limited to the application listed in the specification and the embodiments, and it can be fully applied to various fields suitable for the present application. For those skilled in the art, other modifications can be easily realized, and therefore the present application is not limited to specific details and the figures shown and described herein.

Claims

1. An automatically regulated fluid dynamic circulation valve, characterized in that, The utility model relates to a valve body, which is provided with a main water inlet, a communication water inlet and a mixed water outlet. The nozzle is coaxially provided with a first flow channel, a second flow channel and a contraction section flow channel. The inner wall of the second flow channel is circumferentially provided with an annular limiting block, and the center of the annular limiting block is provided with a spray hole. The spray needle is movably arranged on the spray hole along the axial direction of the nozzle. The spray needle comprises a needle head section and a needle tail section. When the fluid pressure of the main water inlet increases, the high-pressure fluid compresses the adjusting spring, pushes the spray needle to move towards the mixed water outlet, increases the gap between the positive taper section and the inner wall of the spray hole, accelerates the formation of negative pressure at the communication water inlet, and strengthens the negative pressure injection. When the fluid pressure of the main water inlet decreases, the adjusting spring rebounds, drives the spray needle to move towards the main water inlet, reduces the gap between the positive taper section of the needle tail and the inner wall of the spray hole, and weakens the negative pressure injection. The spring seat is threadedly connected with the end of the needle head section, and is provided with a pressure receiving surface perpendicular to the axial line of the spray needle.

2. The self-regulating fluid dynamic recirculation valve according to claim 1, wherein The rigidity coefficient of the adjusting spring and the fluid rated pressure range of the main water inlet satisfy: k=(0.15~0.3)P max ×A / Δx, wherein k is the spring rigidity coefficient (N / mm), P max is the maximum pump starting pressure of the main water inlet (MPa), Δx is the maximum stroke displacement amount of the needle (mm), and A is the pressure receiving area of the needle head section (mm²).

3. The self-regulating fluid dynamic recirculation valve according to claim 2, wherein, The pre-tightening force F0 of the adjusting spring and the minimum pump starting pressure and the maximum pump starting pressure of the main water inlet satisfy: F0=0.12 P max ×A+0.3 P min ×A, wherein A is the pressure receiving area (mm2) of the needle segment, P min is the minimum pump starting pressure, and P max is the maximum pump starting pressure.

4. The self-regulating fluid dynamic recirculation valve according to claim 3, wherein The needle head section comprises a spray needle body, a plurality of convex rib sections uniformly distributed along the circumferential direction of the spray needle body and arranged along the axial direction of the spray needle body.

5. The self-regulating fluid dynamic recirculation valve according to claim 2, wherein, The convex rib section comprises a first convex rib part and a second convex rib part.

6. The self-regulating fluid dynamic orifice valve of claim 5, wherein, The inner wall of the nozzle is formed with a slot corresponding to the second convex rib part. The contraction section flow channel comprises a mixing water section and a diffusion section arranged in sequence from the water inlet end to the water outlet end.

7. The self-regulating fluid dynamic recirculation valve according to claim 1, wherein, The needle tail section is provided with a reverse taper section at the end.

8. The self-regulating fluid dynamic orifice circulation valve of claim 1, wherein, The taper angle of the reverse taper section is 10-25°.

9. The self-regulating fluid dynamic recirculation valve according to claim 8, wherein, The reverse taper section is extended to form a guide boss, and the outer diameter of the guide boss and the minimum gap between the inner wall of the second flow channel are 0.5-1.2 mm.

10. The self-regulating fluid dynamic recirculation valve according to claim 1, wherein, The valve body is provided with a branch water outlet at the upstream end of the first fluid. The utility model further comprises a branch pipe, which is in communication with the branch water outlet and the communication water inlet at both ends.

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