Differential pressure switch valve

Abstract

The utility model relates to the technical field of differential pressure switch valves, in particular to a differential pressure switch valve. The differential pressure switch valve is used in a valve device with a fluid inlet pipe and a fluid outlet pipe, the differential pressure switch valve comprises a discharge pipe and a valve element assembly, one end of the discharge pipe is communicated with the fluid inlet pipe, a pressure bearing opening is formed in the communication position of the discharge pipe and the fluid inlet pipe, and one side of the discharge pipe is communicated with the fluid outlet pipe. When the communicating channel of the fluid inlet pipe and the fluid outlet pipe is closed, the discharge pipe can discharge fluid flowing back into the fluid outlet pipe. The valve element assembly comprises a main valve element and an elastic piece, and the main valve element is movably installed in the discharging pipe through the elastic piece and blocks the pressure bearing opening. When fluid enters the fluid inlet pipe, the main valve element compresses the elastic piece and closes the discharge pipe. And when the fluid inlet pipe stops introducing the fluid, the main valve element can open the discharge pipe under the driving of the elastic piece. When the fluid inlet pipe stops introducing the fluid, the main valve element opens the discharge pipe, and the situation that the fluid flows back in the fluid discharge pipe and pollutes a pipeline where the valve device is located is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of differential pressure switch valves, in particular to a differential pressure switch valve. Background Art

[0002] A switch valve is installed in the pipe for supplying hot water or warm water from a hot water supply device to a water-using end. Two one-way valve cores are arranged at intervals in the water outlet pipe of the switch valve. After the hot water passes through the pipe, it enters the switch valve, and then flows out from the discharge port of the water outlet pipe to the water-using end after passing through the two one-way valve cores. Since the one-way valve cores in the water outlet pipe are prone to wear and other conditions after long-term use, after the switch valve stops supplying water, the water at the water-using end is likely to flow back into the water inlet pipe, thereby polluting the pipeline where the switch valve is located. Content of the Utility Model

[0003] The purpose of the utility model is to provide a differential pressure switch valve to achieve reliable on-off of the valve device and avoid residual fluid in the fluid discharge pipe or fluid backflow to pollute the pipeline where the valve device is located.

[0004] To achieve this purpose, the technical solution adopted by the utility model is as follows:

[0005] A differential pressure switch valve is used in a valve device with a fluid inlet pipe and a fluid discharge pipe. The differential pressure switch valve includes:

[0006] A discharge pipe, one end of the discharge pipe is communicated with the fluid inlet pipe and a pressure-bearing port is formed at the communication position, and one side of the discharge pipe is communicated with the fluid discharge pipe; when the communication channel between the fluid inlet pipe and the fluid discharge pipe is closed, the fluid flowing back into the fluid discharge pipe can be discharged through the discharge pipe;

[0007] A valve core assembly, the valve core assembly includes a main valve core and an elastic member. The main valve core is movably installed in the discharge pipe through the elastic member and blocks the pressure-bearing port; when there is fluid entering the fluid inlet pipe, the main valve core compresses the elastic member and closes the discharge pipe; when the fluid inlet pipe stops passing fluid, the main valve core can open the discharge pipe under the drive of the elastic member.

[0008] As an optional solution of the differential pressure switch valve, the main valve core includes:

[0009] A pressure-bearing pad, the pressure-bearing pad is axially telescopically arranged in the discharge pipe and blocks the pressure-bearing port;

[0010] Plug, the first end of the plug in the axial direction is arranged on the pressure-bearing pad. When fluid enters the fluid inlet pipe, the pressure-bearing pad extends towards the inside of the discharge pipe and drives the second end of the plug in the axial direction to close the discharge pipe. When the fluid inlet pipe stops supplying fluid, the plug compresses the pressure-bearing pad under the drive of the elastic member and opens the discharge pipe.

[0011] As an alternative to the differential pressure switch valve, the pressure-bearing area of the pressure-bearing pad on the side facing the fluid inlet pipe is larger than the pressure-bearing area of the pressure-bearing pad on the side facing the discharge pipe.

[0012] As an alternative to the differential pressure switch valve, the pressure-bearing area of the pressure-bearing pad on the side facing the discharge pipe is larger than the end face area of the second end of the plug in the axial direction.

[0013] As an alternative to the differential pressure switch valve, the discharge pipe includes:

[0014] Main body pipe, one end of the main body pipe is communicated with the fluid inlet pipe and forms the pressure-bearing port at the communication position, and one side of the main body pipe is communicated with the fluid discharge pipe;

[0015] Pressure relief seat, one end of the pressure relief seat is sealed and sleeved inside the main body pipe, and the circumferential edge of the pressure-bearing pad is sealed and clamped between the main body pipe and the pressure relief seat; the other end of the pressure relief seat extends out of the main body pipe and is provided with a discharge port, and the plug is installed in the pressure relief seat through the elastic member and can open or close the discharge port.

[0016] As an alternative to the differential pressure switch valve, there is a pressure relief cavity inside the pressure relief seat, and the inner cavity of the main body pipe is communicated with the pressure relief cavity; a release port coaxial with the discharge port is opened on the inner bottom wall of the pressure relief cavity, and the plug can block or open the discharge port.

[0017] As an alternative to the differential pressure switch valve, a ring groove is circumferentially arranged around the release port on the inner bottom wall of the pressure relief cavity, one end of the elastic member is connected to the first end of the plug, and the other end of the elastic member abuts tightly in the ring groove.

[0018] As an alternative to the differential pressure switch valve, the plug includes:

[0019] Rod part, one end of the rod part is arranged inside the pressure-bearing pad, and the elastic member is sleeved on the rod part;

[0020] Sealing pad, the other end of the rod part is provided with the sealing pad, and the sealing pad can open or close the discharge pipe.

[0021] As an alternative to the differential pressure switch valve, a positioning groove is opened at the other end of the rod part, and the sealing pad is snap-fitted and installed in the positioning groove.

[0022] As an alternative to the differential pressure switch valve, the elastic member is a pagoda-shaped spring.

[0023] The beneficial effects of the present utility model are as follows:

[0024] For the differential pressure switch valve proposed by the present utility model, by arranging a differential pressure switch valve in the valve device, when there is fluid entering the fluid inlet pipe, the main valve core compresses the elastic member and closes the discharge pipe, preventing fluid leakage in the fluid discharge pipe; when the fluid inlet pipe stops supplying fluid, the main valve core is driven by the elastic member to open the discharge pipe, enabling the fluid in the fluid discharge pipe to be discharged from the discharge pipe, avoiding residual fluid in the fluid discharge pipe or fluid backflow to contaminate the pipeline where the valve device is located, and achieving reliable on-off of the valve device. Description of the Drawings

[0025] Figure 1 is a schematic structural diagram of the differential pressure switch valve provided by an embodiment of the present utility model;

[0026] Figure 2 is a cross-sectional view of the differential pressure switch valve provided by an embodiment of the present utility model;

[0027] Figure 3 is a schematic structural diagram of the valve core assembly provided by an embodiment of the present utility model;

[0028] Figure 4 is a schematic structural diagram of the pressure relief seat provided by an embodiment of the present utility model.

[0029] The names and labels of the components in the figure are as follows:

[0030] 1, fluid inlet pipe; 11, pressure-bearing port; 12, inlet; 2, fluid discharge pipe; 20, drainage channel; 21, discharge port; 22, round pipe; 3, discharge pipe; 31, main body pipe; 32, pressure relief seat; 321, discharge port; 322, through hole; 323, pressure relief cavity; 3230, annular groove; 324, release port; 4, valve core assembly; 41, pressure-bearing pad; 42, plug; 421, rod part; 4211, positioning groove; 422, sealing pad; 43, elastic member; 5, switch valve group; 51, outer shell; 52, moving iron core; 53, sealing seat; 6, filter membrane; 7, first check valve; 8, second check valve. Detailed Embodiments

[0031] To make the technical problems solved by the present utility model, the technical solutions adopted, and the achieved technical effects clearer, the technical solutions of the present utility model will be further described below with reference to the accompanying drawings and through specific embodiments. It can be understood that the specific embodiments described herein are only used to explain the present utility model and are not intended to limit the present utility model. Additionally, it should be noted that for the sake of description, only the parts related to the present utility model are shown in the drawings rather than all of them.

[0032] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0033] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "over", and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below", "beneath", and "underneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0034] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", and "left" are based on the orientation or positional relationships shown in the drawings. It is only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and do not have any special meanings.

[0035] The technical solutions of the present utility model will be further described below with reference to the accompanying drawings and through specific embodiments.

[0036] Such as Figure 1 and Figure 2As shown in the figure, in this embodiment, a differential pressure switch valve is proposed. This differential pressure switch valve is used in a valve device with a fluid inlet pipe 1 and a fluid outlet pipe 2. The valve device in this embodiment can be a hot water injection valve, and the fluid correspondingly is hot water or warm water. The hot water injection valve is mainly installed in the pipe in the hot water supply system to introduce the warm water from the hot water supply device into the bathtub. When the bathtub is located at a higher position than the hot water supply device, the hot water injection valve can prevent the sewage in the bathtub from flowing back into the tap water pipe. Of course, the differential pressure switch valve can also be installed in other valve devices, and the above-mentioned fluid can correspondingly be air or other fluid media, which will not be specifically limited here.

[0037] For the convenience of description, the following takes the valve device as a hot water injection valve and the fluid as hot water or warm water as an example for specific description. The differential pressure switch valve in this embodiment includes a discharge pipe 3 and a valve core assembly 4. One end of the discharge pipe 3 is connected to the fluid inlet pipe 1 and a pressure-bearing port 11 is formed at the connection. One side of the discharge pipe 3 is connected to the fluid outlet pipe 2. When the communication channel between the fluid inlet pipe 1 and the fluid outlet pipe 2 is closed, the fluid flowing back into the fluid outlet pipe 2 can be discharged through the discharge pipe 3. The valve core assembly 4 includes a main valve core and an elastic member 43. The main valve core is movably installed in the discharge pipe 3 through the elastic member 43 and blocks the pressure-bearing port 11. When there is fluid entering the fluid inlet pipe 1, the main valve core compresses the elastic member 43 and closes the discharge pipe 3; when the fluid inlet pipe 1 stops passing fluid, the main valve core can open the discharge pipe 3 under the drive of the elastic member 43.

[0038] By setting a differential pressure switch valve in the hot water injection valve, when there is fluid entering the fluid inlet pipe 1, the main valve core compresses the elastic member 43 and closes the discharge pipe 3 to prevent fluid leakage in the fluid outlet pipe 2; when the fluid inlet pipe 1 stops passing fluid, the main valve core opens the discharge pipe 3 under the drive of the elastic member 43, so that the fluid in the fluid outlet pipe 2 is discharged from the discharge pipe 3, avoiding the residual fluid in the fluid outlet pipe 2 or the occurrence of fluid backflow polluting the pipeline where the hot water injection valve is located, and realizing the reliable on-off of the valve device.

[0039] As Figure 1 and Figure 2As shown in the figure, the hot water injection valve further includes a switching valve group 5. The fluid inlet pipe 1 is used to introduce hot water. The fluid outlet pipe 2 is cross-connected to the fluid inlet pipe 1 to draw out hot water. A first check valve 7 and a second check valve 8 are separately arranged in the fluid outlet pipe 2. The switching valve group 5 is arranged on the communication path between the fluid inlet pipe 1 and the fluid outlet pipe 2 to open or cut off the communication path. Specifically, there is an inlet 12 in the fluid inlet pipe 1 for hot water to enter the hot water injection valve, and a filter membrane 6 is installed on the part of the fluid inlet pipe 1 near the inlet 12 to filter the water in the fluid inlet pipe 1. There is an outlet 21 in the fluid outlet pipe 2 for hot water to flow out of the hot water injection valve. The first check valve 7 and the second check valve 8 are installed at intervals in the fluid outlet pipe 2 to make the water in the fluid outlet pipe 2 flow unidirectionally towards the outlet 21.

[0040] As Figure 2 shown in the figure, one end of the fluid outlet pipe 2 is integrally connected to the end of the fluid inlet pipe 1 far from the inlet 12 at a right angle. The switching valve group 5 is installed on the communication path between the fluid outlet pipe 2 and the fluid inlet pipe 1. A circular pipe 22 is arranged along the extending direction (i.e., the axial direction) of the fluid outlet pipe 2 at the connection between the fluid outlet pipe 2 and the fluid inlet pipe 1. The fluid inlet pipe 1, the circular pipe 22 and the fluid outlet pipe 2 are connected. The switching valve group 5 is located on the axis of the fluid outlet pipe 2 and can open or close the circular pipe 22.

[0041] The switching valve group 5 of this embodiment is an electromagnetic valve. When the electromagnetic valve is energized, the circular pipe 22 is opened. When the electromagnetic valve is de-energized, the circular pipe 22 is closed. The structure of the electromagnetic valve is simple and it is convenient for installation and maintenance. By controlling the electromagnetic valve, the automatic opening and closing of the circular pipe 22 is realized, and thus the automatic opening and closing of the hot water injection valve is realized.

[0042] Specifically, the switching valve group 5 includes a housing 51, a moving iron core 52 and a sealing seat 53. Among them, the housing 51 is fixedly installed on the communication path between the fluid outlet pipe 2 and the fluid inlet pipe 1 through fasteners such as bolts. The moving iron core 52 is movably arranged in the housing 51. The sealing seat 53 is hermetically installed on the inner wall at the intersection of the fluid outlet pipe 2 and the fluid inlet pipe 1 and blocks the opening of the circular pipe 22. An electromagnetic coil is installed in the housing 51. When the electromagnetic coil is de-energized, the moving iron core 52 extends out of the housing 51 and abuts against the sealing seat 53 to block the circular pipe 22, thereby isolating the fluid inlet pipe 1 and the fluid outlet pipe 2 and closing the hot water injection valve. When the electromagnetic coil is energized, the moving iron core 52 retracts into the housing 51, and the sealing seat 53 opens the circular pipe 22 under the action of the water pressure in the fluid inlet pipe 1, so that the fluid inlet pipe 1 and the fluid outlet pipe 2 are connected and the hot water injection valve is opened. Since the electromagnetic valve is a prior art, the specific structure and working process of the electromagnetic valve will not be elaborated here.

[0043] As Figure 2As shown, the drain pipe 3 is arranged inside the connecting corner of the fluid inlet pipe 1 and the fluid outlet pipe 2. The drain pipe 3 communicates with the chamber between the first one-way valve 7 and the second one-way valve 8 to drain the water accumulated in the chamber between the first one-way valve 7 and the second one-way valve 8. By installing the drain pipe 3 inside the connecting corner of the fluid inlet pipe 1 and the fluid outlet pipe 2, the internal flow path and the overall structure of the hot water injection valve are optimized, the volume and occupied space of the hot water injection valve are reduced, the structural strength of the hot water injection valve is improved, which is beneficial to extending the service life of the hot water injection valve.

[0044] Furthermore, the fluid outlet pipe 2 is integrally connected to the drain pipe 3. A drainage channel 20 is provided between the fluid outlet pipe 2 and the drain pipe 3. The chamber between the first one-way valve 7 and the second one-way valve 8 communicates with the inlet of the drainage channel 20, and the outlet of the drainage channel 20 communicates with the drainage chamber inside the drain pipe 3. The water accumulated in the chamber between the first one-way valve 7 and the second one-way valve 8 enters the drainage chamber through the drainage channel 20 and then flows out from the drain port 321. Since the fluid inlet pipe 1, the fluid outlet pipe 2 and the drain pipe 3 are integrally formed, the fluid inlet pipe 1 and the fluid outlet pipe 2 are orthogonally connected, and the drain pipe 3 is located at the right-angle bend of the fluid inlet pipe 1 and the fluid outlet pipe 2, the fluid inlet pipe 1, the fluid outlet pipe 2 and the drain pipe 3 form a right-angle support frame structure, which improves the structural strength and installation stability of the hot water injection valve.

[0045] It should be noted that, as Figure 2 shown, the drainage channel 20 is arranged to slope downward from the inlet to the outlet, and the outlet of the drainage channel 20 communicates with the bottom of the drainage chamber. The inlet of the drainage channel 20 in this embodiment is located between the first one-way valve 7 and the second one-way valve 8, so that the water flowing back to the fluid outlet pipe 2 directly flows into the bottom of the drainage chamber through the drainage channel 20.

[0046] Furthermore, the inclination angle of the drainage channel 20 is 20° to 70°. Specifically, the inclination angle of the drainage channel 20 can be 20°, 30°, 40°, 50°, 60° or 70°, etc. The drainage channel 20 can flexibly adjust the inclination angle according to its own axial length, as long as it is ensured that the outlet of the drainage channel 20 communicates with the bottom of the drainage chamber.

[0047] As Figure 2 and Figure 3As shown, the main spool valve includes a pressure-bearing pad 41 and a plug 42. The pressure-bearing pad 41 is axially telescopically arranged in the discharge pipe 3 and seals the pressure-bearing port 11. The first end of the plug 42 in the axial direction is arranged on the pressure-bearing pad 41. When fluid enters the pipe 1, the pressure-bearing pad 41 extends into the discharge pipe 3 and drives the second end of the plug 42 in the axial direction to close the discharge pipe 3. When the fluid supply to the pipe 1 stops, the plug 42 compresses the pressure-bearing pad 41 under the drive of the elastic member 43 and opens the discharge pipe 3. By sealing the pressure-bearing port 11 with the pressure-bearing pad 41, it is avoided that the water in the fluid inlet pipe 1 directly enters the discharge pipe 3. The elastic member 43 is compressively installed on the plug 42, so that the plug 42 always has a tendency to move upward to the initial position (the position where the discharge pipe 3 is opened) to ensure that when the fluid supply to the pipe 1 stops, the plug 42 is driven to move to the initial position, so that the plug 42 opens the discharge pipe 3 when the fluid supply to the pipe 1 stops.

[0048] As Figure 2 and Figure 4 shown, the discharge pipe 3 includes a main body pipe 31 and a pressure relief seat 32. One end of the main body pipe 31 is connected to the fluid inlet pipe 1 and a pressure-bearing port 11 is formed at the connection. One side of the main body pipe 31 is connected to the fluid discharge pipe 2. One end of the pressure relief seat 32 is hermetically sleeved in the main body pipe 31, and the circumferential edge of the pressure-bearing pad 41 is hermetically clamped between the main body pipe 31 and the pressure relief seat 32. The other end of the pressure relief seat 32 extends out of the main body pipe 31 and is provided with a discharge port 321. The plug 42 is installed in the pressure relief seat 32 through the elastic member 43 and can open or close the discharge port 321. The discharge pipe 3 is set as a split structure of the main body pipe 31 and the pressure relief seat 32, so that the fluid inlet pipe 1, the fluid discharge pipe 2 and the main body pipe 31 are integrally formed, which is convenient for the disassembly, replacement and installation of the spool valve assembly 4.

[0049] Specifically, a pressure relief cavity 323 is provided in the pressure relief seat 32, and the inner cavity of the main body pipe 31 is communicated with the pressure relief cavity 323. A release port 324 coaxially communicated with the discharge port 321 is provided on the inner bottom wall of the pressure relief cavity 323, and the plug 42 can block or open the discharge port 321. Two symmetrically arranged through holes 322 are provided on the pressure relief seat 32, so that the inner cavity of the main body pipe 31 is communicated with the pressure relief cavity 323 through the two through holes 322. The water flowing in through the drainage channel 20 sequentially flows through the inner cavity of the main body pipe 31, the through holes 322 and the pressure relief cavity 323 and then enters the release port 324, and finally is discharged from the discharge port 321.

[0050] The release port 324 of this embodiment is coaxially arranged with the discharge port 321, that is, the water flow will not change direction during the process of flowing from the release port 324 to the discharge port 321, so as to achieve smooth drainage and avoid residual water in the discharge pipe 3. Specifically, the aperture of the release port 324 is smaller than that of the discharge port 321, so that the opening area of the release port 324 is smaller, improving the plugging effect of the valve core assembly 4 on the release port 324 and avoiding water leakage due to the too large aperture of the release port 324 resulting in poor sealing.

[0051] The pressure-bearing pad 41 of this embodiment is a rubber bowl, and the circumferential edge of the rubber bowl is clamped between the inner wall of the main pipe 31 and the top end of the pressure-relief seat 32 to achieve good sealing of the pressure-bearing port 11. The pressure-bearing area of the pressure-bearing pad 41 facing the fluid inlet pipe 1 is larger than the pressure-bearing area of the pressure-bearing pad 41 facing the discharge pipe 3. When water enters the fluid inlet pipe 1, the pressure-bearing pad 41 extends towards the discharge pipe 3 under the influence of the pressure difference and compresses the elastic member 43 to drive the plug 42 to block the release port 324. When the water supply in the fluid inlet pipe 1 stops, under the action of the restoring force of the elastic member 43, the pressure-bearing pad 41 contracts and drives the plug 42 to open the release port 324. The pressure difference of the pressure-bearing pad 41 is greater than the restoring force of the elastic member 43 to ensure that the pressure-bearing pad 41 can drive the plug 42 to block the release port 324 when affected by the pressure difference.

[0052] As Figure 4 shown, the plug 42 includes a rod portion 421 and a sealing pad 422. One end of the rod portion 421 is arranged inside the pressure-bearing pad 41, and the elastic member 43 is sleeved on the rod portion 421. The other end of the rod portion 421 is provided with a sealing pad 422, and the sealing pad 422 can open or close the discharge pipe 3. The sealing pad 422 of this embodiment is a rubber pad. When the plug 42 blocks the release port 324, the sealing pad 422 is pressed tightly at the release port 324 to achieve the sealing of the release port 324. Specifically, a positioning groove 4211 is formed at the other end of the rod portion 421, and the sealing pad 422 is snap-fitted into the positioning groove 4211, so that the sealing pad 422 is firmly installed on the rod portion 421. At the same time, when the sealing pad 422 is worn or damaged, it is convenient to quickly replace the sealing pad 422.

[0053] Furthermore, the pressure-bearing area of the pressure-bearing pad 41 facing the discharge pipe 3 is larger than the end face area of the second end of the plug 42 in the axial direction. As Figure 3As shown, the end face area of the second end of the plug 42 in the axial direction may only refer to the area S1 of the gasket 422 at the second end of the plug 42, or may refer to the total area enclosed by the outer edge contour of the second end of the plug 42 in the axial direction (i.e., the sum of S1 and S2), where S2 is the actual area of the rod portion 421 at the second end of the plug 42 in the axial direction. Since the pressure-bearing areas of the pressure-bearing pad 41 on the side facing the fluid inlet pipe 1 and the pressure-bearing area of the pressure-bearing pad 41 on the side facing the discharge pipe 3 gradually become smaller than the end face area of the second end of the plug 42 in the axial direction, an area difference is formed among the three, so that a pressure difference is formed between the pressure-bearing pad 41 and the gasket 422, ensuring that the pressure-bearing pad 41 drives the plug 42 to stably block the release port 324 after water enters the fluid inlet pipe 1. Moreover, the greater the water pressure in the fluid inlet pipe 1, the better the blocking effect of the plug 42 on the release port 324.

[0054] As Figure 2 and Figure 3 shown, a ring groove 3230 is circumferentially arranged on the inner bottom wall of the pressure relief chamber 323 around the release port 324. One end of the elastic member 43 is connected to the first end of the plug 42, and the other end of the elastic member 43 abuts tightly in the ring groove 3230. The ring groove 3230 plays a role in limiting the installation of the elastic member 43, improving the stability of the installation of the elastic member 43.

[0055] The elastic member 43 in this embodiment is a conical spring. The structure of the conical spring is simple and convenient for installation. At the same time, the conical spring has good structural stability itself, avoiding driving the plug 42 to shake left and right, and improving the stability of the plug 42 moving in the up and down direction to ensure that the gasket 422 reliably blocks the release port 324.

[0056] The above embodiments only illustrate the basic principles and characteristics of the present invention. The present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, there are various changes and modifications to the present invention, and these changes and modifications all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A pressure differential switching valve, used in a valve device having a fluid inlet pipe (1) and a fluid outlet pipe (2), characterized in that: The differential pressure switch valve comprises: a discharge pipe (3), one end of which is in communication with the fluid inlet pipe (1) and a pressure-bearing port (11) is formed at the communication point, and one side of the discharge pipe (3) is in communication with the fluid outlet pipe (2); when the communication passage between the fluid inlet pipe (1) and the fluid outlet pipe (2) is closed, the fluid that has flowed back into the fluid outlet pipe (2) can be discharged through the discharge pipe (3); A valve core assembly (4), the valve core assembly (4) comprising a main valve core and an elastic member (43), the main valve core being movably mounted in the discharge pipe (3) through the elastic member (43) and sealing the pressure-bearing port (11); when fluid enters the fluid inlet pipe (1), the main valve core compresses the elastic member (43) and closes the discharge pipe (3); when the fluid inlet pipe (1) stops entering the fluid, the main valve core can open the discharge pipe (3) under the drive of the elastic member (43).

2. The differential pressure switch valve according to claim 1, characterized in that: The main valve core comprises: A pressure-bearing pad (41), the pressure-bearing pad (41) being axially telescopically arranged in the discharge pipe (3) and sealing the pressure-bearing port (11); A plug (42), wherein the first axial end of the plug (42) is arranged on the pressure pad (41); when fluid enters the fluid inlet pipe (1), the pressure pad (41) extends toward the discharge pipe (3) and drives the second axial end of the plug (42) to close the discharge pipe (3); when the fluid inlet pipe (1) stops flowing with fluid, the plug (42) compresses the pressure pad (41) and opens the discharge pipe (3) under the drive of the elastic member (43).

3. The differential pressure switch valve according to claim 2, characterized in that: The pressure-bearing area of ​​the pressure-bearing pad (41) on the side facing the fluid inlet pipe (1) is greater than the pressure-bearing area of ​​the pressure-bearing pad (41) on the side facing the discharge pipe (3).

4. The differential pressure switch valve according to claim 3, characterized in that: The pressure-bearing area of ​​the pressure-bearing pad (41) on the side facing the discharge pipe (3) is larger than the end surface area of ​​the second axial end of the plug (42).

5. The differential pressure switch valve according to claim 2, characterized in that: The discharge pipe (3) comprises: a main body pipe (31), one end of the main body pipe (31) being in communication with the fluid inlet pipe (1) and forming the pressure-bearing port (11) at the connection point, and one side of the main body pipe (31) being in communication with the fluid outlet pipe (2); A pressure relief seat (32), one end of the pressure relief seat (32) is sealingly sleeved in the main body tube (31), and the circumferential edge of the pressure bearing pad (41) is sealingly clamped between the main body tube (31) and the pressure relief seat (32); the other end of the pressure relief seat (32) extends out of the main body tube (31) and is provided with a discharge port (321), and the plug (42) is installed in the pressure relief seat (32) through the elastic member (43) and is capable of opening or closing the discharge port (321).

6. The differential pressure switch valve according to claim 5, characterized in that: The pressure relief seat (32) has a pressure relief chamber (323) therein, and the inner chamber of the main tube (31) is connected to the pressure relief chamber (323); the inner bottom wall of the pressure relief chamber (323) is provided with a release port (324) coaxially connected to the discharge port (321), and the plug (42) can block or open the discharge port (321).

7. The differential pressure switch valve according to claim 6, characterized in that: The inner bottom wall of the pressure relief chamber (323) is provided with an annular groove (3230) circumferentially around the release port (324); one end of the elastic member (43) is connected to the first end of the plug (42); and the other end of the elastic member (43) is tightly pressed against the annular groove (3230).

8. The differential pressure switch valve according to claim 2, characterized in that: The plug (42) comprises: A rod portion (421), one end of the rod portion (421) is disposed in the pressure pad (41), and the elastic member (43) is sleeved on the rod portion (421); A sealing gasket (422) is provided at the other end of the rod portion (421), and the sealing gasket (422) can open or close the discharge pipe (3).

9. The differential pressure switch valve according to claim 8, characterized in that: The other end of the rod portion (421) is provided with a positioning groove (4211), and the sealing gasket (422) is snap-fitted and installed in the positioning groove (4211).

10. The differential pressure switch valve according to any one of claims 1 to 9, characterized in that: The elastic member (43) is a pagoda-shaped spring.

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