Anti-explosion pressure release valve and sealing structure

Abstract

The utility model discloses an explosion-proof pressure release valve and a closed structure, the explosion-proof pressure release valve comprises: a valve main body provided with a cavity, the cavity is provided with a through hole for connecting with the inside of the closed structure and an air hole for communicating the cavity with the outside; the piston is movably arranged in the cavity and is provided with a middle hole for communicating the air hole with the through hole, and the middle hole is provided with a waterproof and breathable membrane material; a sealing ring is arranged on the side, facing the through hole, of the piston and used for isolating the air hole and the through hole. An elastic piece is arranged between the piston and the inner wall of the valve main body; when the air pressure difference between the interior of the closed structure and the exterior of the valve main body is smaller than a preset value, airflow passes through a passage of the membrane material to the vent hole for pressure relief; when the air pressure difference between the interior of the closed structure and the exterior of the valve body is larger than or equal to a preset value, airflow is decompressed through a passage from the sealing ring to the vent hole. According to the anti-explosion pressure release valve, pressure release can be achieved under the condition of different air pressure states, and the anti-explosion pressure release valve is safe and stable.

Description

Technical Field

[0001] The utility model relates to the technical field of explosion-proof pressure relief, and more specifically, to an explosion-proof pressure relief valve. In addition, the utility model also relates to a closed structure including the explosion-proof pressure relief valve. Background Art

[0002] Common battery packs and closed boxes have dust and water resistance requirements, so the interior of the battery pack and the closed box needs to be designed to be an externally closed structure, and considering the lightweight design, the battery pack box can usually withstand little pressure. When new energy vehicles or energy storage facilities are working, the inside of the battery pack will heat up, causing its internal pressure to rise. This will cause an imbalance in the pressure difference between the inside and outside of the battery pack, which will have an adverse effect on the equipment. When the battery chip unit experiences thermal runaway, the pressure inside the battery pack suddenly rises, causing damage to the battery pack, and then posing a threat to the safety of equipment and personnel. The usual solution is to design an appropriate pressure relief valve to ensure that the air pressure difference inside and outside the battery pack is balanced, reduce potential risks, and quickly release pressure to reduce the harm caused by the battery pack when new energy vehicles or energy storage equipment experience thermal runaway. Therefore, the pressure relief valve has attracted widespread attention and high attention from related industries.

[0003] The problem with the pressure relief valve device disclosed in the prior art is that when the pressure difference between the battery pack and the external environment is not large, the pressure inside and outside the battery pack cannot be well balanced due to the low air permeability of the pressure relief valve. In the event of thermal runaway of the battery chip unit, the large amount of gas released is difficult to be discharged in a shorter time.

[0004] In summary, how to provide an explosion-proof pressure relief valve that meets the safety requirement of balancing the internal and external pressures of a battery pack is a problem that currently needs to be solved urgently by those skilled in the art. Utility Model Content

[0005] In view of this, the purpose of the utility model is to provide an explosion-proof pressure relief valve, which can meet different usage conditions of small pressure difference and large pressure difference, and can safely relieve pressure at the installation location.

[0006] Another object of the utility model is to provide a closed structure including the explosion-proof pressure relief valve.

[0007] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0008] An explosion-proof pressure relief valve, comprising:

[0009] The valve body is provided with a cavity, wherein the cavity is provided with a through hole for connecting with the inside of the closed structure and a vent hole connecting the cavity with the outside;

[0010] A piston is movably disposed in the cavity and has a central hole for connecting the vent hole and the through hole, wherein the central hole is provided with a waterproof and breathable membrane material; a sealing ring is provided on the side of the piston facing the through hole for isolating the vent hole and the through hole; an elastic member is provided between the piston and the inner wall of the valve body;

[0011] When the air pressure difference between the closed structure and the outside of the valve body is less than a preset value, the piston moves toward the through hole under the pressure of the elastic member, and the sealing ring is in a sealed state, so that the air flow passes through the membrane material to the air hole for pressure relief;

[0012] When the air pressure difference between the closed structure and the outside of the valve body is greater than or equal to a preset value, the piston moves and compresses the elastic member to render the sealing ring ineffective, and the air flow is depressurized through the passage from the sealing ring to the air vent.

[0013] Preferably, the valve body comprises:

[0014] The valve body is provided with a concave groove, and the inner bottom of the groove is provided with the through hole;

[0015] A gland is arranged at the port of the groove body and is snap-fitted with the valve body to form the cavity. The air vent is arranged at the connection between the gland and the valve body.

[0016] Preferably, a groove structure is provided on one side of the piston, and the middle hole passes through the inner bottom of the groove structure;

[0017] An annular groove is provided on the other side of the piston, and the sealing ring is provided in the annular groove. When the piston moves to a side close to the valve body, the sealing ring abuts against the inner end surface of the through hole.

[0018] Preferably, the film material is attached to the inner bottom surface of the groove structure of the piston to cover the inner port of the middle hole;

[0019] A fixing ring is arranged on the membrane material, and one end of the elastic member abuts against the fixing ring.

[0020] Preferably, both ends of the middle hole are chamfered.

[0021] Preferably, a step groove is also provided at one end of the center hole located on the inner bottom surface of the groove structure.

[0022] Preferably, one end of the valve body used for connecting to the gland is circumferentially provided with a protrusion and a recess, the protrusion is plug-connected with the gland, and a gap is provided between the recess and the end surface of the gland to form the air vent.

[0023] Preferably, a column is provided on the outside of the valve body, the outside of the column is a threaded structure, and the through hole passes through the column; an annular seal is provided at the connection between the column and the valve body for sealing the opening of the closed structure and the column.

[0024] A closed structure comprises any of the explosion-proof pressure relief valves described above.

[0025] The explosion-proof pressure relief valve provided by the present application is configured with a structure having a movable piston inside the valve body, and the piston is abutted against the bottom of the cavity by the elastic member, so that the sealing ring of the piston forms a circumferential seal on the end of the through hole, so that the gas can only flow upward through the middle hole of the piston and the membrane material, and flow to the air holes on the side of the valve body to release pressure. When the air pressure is high and the pressure release of the above-mentioned passage is not smooth, the high air pressure will push the piston open, and the sealing ring will be separated from the inner bottom wall of the valve body structure, so that the pressure is released through the side of the piston, and the high pressure can be released. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0027] Figure 1 An exploded diagram of an explosion-proof pressure relief valve provided by the utility model;

[0028] Figure 2 A front cross-sectional view of the piston provided by the utility model;

[0029] Figure 3 A schematic diagram of the structure of the valve body provided by the utility model;

[0030] Figure 4 A schematic diagram of the structure of the gland provided by the utility model;

[0031] Figure 5 This is a front view of the explosion-proof pressure relief valve provided by the utility model;

[0032] Figure 6 A cross-sectional view of the explosion-proof pressure relief valve provided by the utility model in a small pressure difference environment;

[0033] Figure 7 This is a cross-sectional view of the explosion-proof pressure relief valve provided by the utility model in a large pressure difference environment.

[0034] Figure 1-Figure 7 middle:

[0035] 1 is a seal, 2 is a valve body, 3 is a seal ring, 4 is a piston, 5 is a membrane material, 6 is a fixing ring, 7 is an elastic part, and 8 is a gland;

[0036] The inner wall of the valve body is 201 and the through hole is 202;

[0037] The annular groove is 401 , the center hole is 402 , the fitting surface is 403 , the piston port is 404 , and the inner wall surface of the piston is 405 . DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0039] The core of the utility model is to provide an explosion-proof pressure relief valve, which can meet different use conditions of small pressure difference and large pressure difference, and can safely relieve pressure at the installation position.

[0040] Another core of the utility model is to provide a closed structure including the above explosion-proof pressure relief valve.

[0041] Please refer to Figures 1 to 7 , Figure 1 An exploded diagram of an explosion-proof pressure relief valve provided by the utility model; Figure 2 A front cross-sectional view of the piston provided by the utility model; Figure 3 A schematic diagram of the structure of the valve body provided by the utility model; Figure 4 A schematic diagram of the structure of the gland provided by the utility model; Figure 5 This is a front view of the explosion-proof pressure relief valve provided by the utility model; Figure 6 A cross-sectional view of the explosion-proof pressure relief valve provided by the utility model in a small pressure difference environment; Figure 7 This is a cross-sectional view of the explosion-proof pressure relief valve provided by the utility model in a large pressure difference environment.

[0042] The present application provides an explosion-proof pressure relief valve, which mainly includes a valve body and a piston 4.

[0043] The valve body is provided with a cavity inside, and the cavity is provided with a through hole 202 for connecting with the inside of the closed structure and an air hole connecting the cavity with the outside.

[0044] The piston 4 is movably arranged in the cavity and has a middle hole 402 for connecting the vent hole and the through hole 202. The middle hole 402 is provided with a waterproof and breathable membrane 5. A sealing ring 3 is provided on the side of the piston 4 facing the through hole 202 to isolate the vent hole and the through hole 202; an elastic member 7 is provided between the piston 4 and the inner wall of the valve body. The movable piston 4 in the cavity specifically refers to the axial movement of the piston 4 in the cavity. Of course, it can also be allowed to rotate in some environments.

[0045] When the above-mentioned explosion-proof pressure relief valve is in use, the side of the valve body provided with the through hole 202 can be inserted into the target structure. The target structure is usually a closed structure with a connecting hole. The side or a part of the valve body provided with the through hole 202 can be inserted into the connecting hole. The plug-in form can keep the through hole 202 and the connecting hole connected to form a stable airflow flow state. The valve body acts as a medium connecting the closed structure with the outside, and the pressure relief of the closed structure is controlled through the valve body.

[0046] The piston 4 in the cavity is subjected to the elastic force of the elastic member 7 and the pressure of the pressurized gas from the communicating position of the through hole.

[0047] When the pressure difference between the closed structure and the outside of the valve body is less than the preset value, please refer to Figure 6 , the elastic force of the elastic member 7 on the piston 4 is significantly greater than the pressure of the pressurized gas, so the piston 4 is moved toward the through hole 202 by the pressure of the elastic member 7, pressing the sealing ring 3 against the inner wall of the cavity and being located at the outer periphery of the through hole 202, so that the port of the through hole 202, the sealing ring 3, the piston 4 and the membrane material 5 form a complete connection state, and the sealing ring 3 is in a state of sealingly connecting the inner wall of the cavity and the piston, so that the airflow has only one pressure relief direction, that is, Figure 6 In the direction of line A, pressure is released through the passage from membrane material 5 to the vent hole.

[0048] When the pressure difference between the closed structure and the outside of the valve body is greater than or equal to the preset value, please refer to Figure 7 , the pressure of the compressed gas on the piston 4 increases to a level significantly greater than the elastic force of the elastic member 7, and the piston 4 moves in the direction of compressing the elastic member 7, causing the sealing ring 3 to separate from the inner wall of the valve body, so that the sealing ring 3 fails, and the airflow is released through the passage from the sealing ring 3 to the air vent. It should be noted that there is a gap between the circumference of the piston 4 and the inner wall 201 of the valve body, so when the sealing ring 3 separates from the inner wall of the valve body, the airflow can flow from the bottom of the valve body to the side of the piston 4, and then flow out through the air vent on the side of the valve body, that is, Figure 7 Middle B airflow direction.

[0049] The explosion-proof pressure relief valve provided by the present application is provided with a structure having a movable piston 4 inside the valve body, and the piston 4 is abutted against the bottom of the cavity by the elastic member, so that the sealing ring of the piston 4 forms a circumferential seal on the end of the through hole, so that the gas can only flow upward through the middle hole of the piston 4 and the membrane material 5, and flow to the air holes on the side of the valve body to release pressure. When the air pressure is high and the pressure relief of the above-mentioned passage is not smooth, the high air pressure will push open the piston 4, causing the sealing ring 3 to fail, thereby releasing pressure through the side of the piston 4, and achieving the release of high pressure.

[0050] On the basis of the above embodiment, the valve body includes a valve body 2 and a gland 8, wherein the valve body 2 is provided with a concave groove, and the inner bottom of the groove is provided with a through hole 202. The gland 8 is provided at the port of the groove, and is snap-fitted with the valve body 2 to form a cavity, and the air vent is provided at the connection between the gland 8 and the valve body 2.

[0051] Please refer to Figure 1 , Figure 2 and Figure 6 The valve body 2 and the gland 8 are designed to be snap-fitted, and specifically can be plug-in snap-fitted, where the two are fixedly connected by plugging, or other snap-fitting methods can be used.

[0052] A through hole 202 is provided at the bottom of the valve body 2, which is connected to the concave groove structure on the other side, and the groove is used to accommodate the piston 4 and the elastic member 7. The gland 8 is located on one side of the groove structure and is buckled with the valve body to form a cavity. Compared with the middle part of the piston 4 and the side close to the bottom of the valve body 2, the piston port 404 on the end face of the side where the piston 4 is provided with the groove can have an annular protrusion structure, which can form a layer of sealing effect behind the sealing ring 3 when contacting the inner wall of the valve body.

[0053] On the basis of the above embodiment, a groove structure is provided on one side of the piston 4, and the middle hole 402 passes through the inner bottom of the groove structure;

[0054] An annular groove 401 is provided on the other side of the piston 4 , and the sealing ring 3 is provided in the annular groove 401 . When the piston 4 moves to a side close to the valve body 2 , the sealing ring 3 abuts against the inner end surface of the through hole 202 .

[0055] The above-mentioned groove structure is a groove at the upper end of the piston 4, which is used to contact and accommodate the end of the elastic member 7. Optionally, the elastic member 7 and the piston inner wall surface 405 of the piston have a certain distance in the radial direction.

[0056] A sealing ring 3 is disposed in the annular groove 401 , and the sealing ring 3 is used to abut against the inner bottom of the valve body 2 , thereby forming a sealing state.

[0057] By configuring the piston 4 to have a structure with an annular groove 401 , it is possible to facilitate the configuration of the sealing ring 3 and avoid positional deviation of the sealing ring 3 .

[0058] Based on any one of the above embodiments, the membrane material 5 is fitted on the inner bottom surface of the groove structure of the piston 4, and is used to cover the inner port of the center hole 402, and cover the fitting surface 403 of the inner bottom of the piston 4; a fixing ring is provided on the membrane material 5, and one end of the elastic member 7 abuts against the fixing ring 6.

[0059] It should be noted that the membrane material 5 is a material structure that is convenient for ventilation, but the ventilation efficiency is limited. When the air pressure is high, the membrane material 5 cannot quickly pass a large amount of high-pressure gas, and thus will form an instant closed structure with the piston 4, the sealing ring 3 and the inner bottom wall of the valve body 2, and the high-pressure gas will push the piston 4 to move.

[0060] The fixing ring 6 is arranged in close contact with the membrane material 5, and the pressure of the elastic member 7 is used to make the membrane material 5 better fit the inner bottom of the groove of the piston 4, thereby forming a stable air permeability effect.

[0061] The membrane material 5 needs to cover the end of the middle hole 402 , and the fixing ring 6 needs to be located on the outer end surface of the middle hole 402 and surround the end of the middle hole 402 .

[0062] In this embodiment, a fixing ring is provided on the membrane material 5 at the end of the middle hole 402 , and the membrane material 5 is pressed by the force of the elastic member 7 , so that the membrane material 5 is fixed.

[0063] Optionally, both ends of the middle hole 402 have chamfers, wherein the chamfers may be oblique chamfers or round chamfers.

[0064] On the basis of the above-mentioned embodiment, a step groove is further provided at one end of the middle hole 402 located on the inner bottom surface of the groove structure.

[0065] Please refer to Figure 2 Among them, at the upper end of the middle hole 402, that is, the end facing the elastic member 7, there is a step groove, and the membrane material 5 is attached to the outer end surface of the step groove. The existence of the step groove expands the end area of ​​the middle hole 402, facilitating the smooth flow of airflow.

[0066] Based on any of the above embodiments, one end of the valve body 2 used for connecting to the gland 8 is circumferentially provided with a protrusion and a recess, the protrusion is plugged into the gland, and a gap is provided between the recess and the end surface of the gland 8 to form an air vent.

[0067] The end face of the valve body 2 presents a rectangular wave structure along the circumferential direction. When the valve body 2 and the gland 8 are plugged in, the protruding part of the rectangular wave contacts or partially overlaps with the gland 8, and there is a gap between the concave part of the rectangular wave and the gland 8, forming the above-mentioned air vents.

[0068] Optionally, holes with fixed positions and shapes may be provided on the side wall surface of the valve body 2 as vent holes.

[0069] Based on any of the above embodiments, a column is provided on the outside of the valve body, the outside of the column is a threaded structure, and a through hole 202 runs through the column; an annular seal 1 is provided at the connection between the column and the valve body to seal the opening of the closed structure and the column.

[0070] Please refer to Figure 6 and Figure 7 A stud structure is provided at the lower part of the valve body 2, and the center of the stud structure has the above-mentioned through hole 202, which is used to connect the closed structure and the inside of the valve body structure. The external thread is used to achieve the connection, and an annular seal 1 is provided at the root of the stud structure to strengthen the airtightness between the connection hole and the closed structure.

[0071] Optionally, the sealing member 1 at the above position may also be arranged on the closed structure.

[0072] In addition to the main structure of the explosion-proof pressure relief valve provided in each of the above embodiments, the utility model also provides a closed structure including the explosion-proof pressure relief valve disclosed in the above embodiments, the closed structure has a connecting hole, the explosion-proof pressure relief valve and the closed structure are plugged and arranged so that the through hole of the explosion-proof pressure relief valve is connected to the connecting hole of the closed structure, when the two holes are connected, the explosion-proof pressure relief valve can relieve the pressure in the closed structure through the connecting effect, thereby relieving the high pressure inside the closed structure and avoiding the situation of excessive pressure. The above closed structure can be a sealed battery pack or a sealed box.

[0073] The size and form of the connection hole can be adjusted according to actual conditions and are not limited to round holes. The structures of other parts of the closed structure can be referred to the prior art and will not be described in detail herein.

[0074] In summary, the present application provides an explosion-proof pressure relief valve, a pressure relief valve with a dustproof grade of IP67, which reduces the internal and external pressure difference of the battery pack or the closed box through high air permeability, reduces the negative impact of the pressure difference on the battery pack or the closed box, and can quickly relieve pressure when the battery pack is thermally runaway. At the same time, the performance of the pressure relief valve developed in this project can be unaffected when the vehicle is driving on muddy roads and washing vehicles, and when the temperature is different in winter and summer. On the premise of complying with international standards, how to ensure that a product is breathable, dustproof, waterproof, fire-resistant, and can be recycled and save costs.

[0075] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0076] The explosion-proof pressure relief valve and the closed structure provided by the utility model are introduced in detail above. This article uses specific examples to illustrate the principle and implementation method of the utility model. The description of the above embodiment is only used to help understand the method and core idea of ​​the utility model. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.

Claims

1. An explosion-proof pressure relief valve, It is characterized in that include: The valve body is provided with a cavity, wherein the cavity is provided with a through hole (202) for connecting with the inside of the closed structure and an air hole connecting the cavity with the outside; A piston (4) is movably disposed in the cavity and has a central hole (402) for connecting the air vent and the through hole (202), wherein the central hole (402) is provided with a waterproof and breathable membrane (5); a sealing ring (3) is provided on the side of the piston (4) facing the through hole (202) for isolating the air vent from the through hole (202); an elastic member (7) is provided between the piston (4) and the inner wall of the valve body; When the air pressure difference between the closed structure and the outside of the valve body is less than a preset value, the piston (4) is moved toward the through hole (202) by the pressure of the elastic member (7), and the sealing ring (3) is in a sealed state, so that air flows through the membrane material (5) to the air vent for pressure relief; When the air pressure difference between the closed structure and the outside of the valve body is greater than or equal to a preset value, the piston (4) moves and compresses the elastic member (7) to render the sealing ring (3) ineffective, and the air flow is depressurized through the passage from the sealing ring (3) to the air vent.

2. The explosion-proof pressure relief valve according to claim 1, It is characterized in that The valve body comprises: The valve body (2) is provided with a concave groove, and the inner bottom of the groove is provided with the through hole (202); A pressure cover (8) is arranged at the port of the groove body and is snap-fitted and connected with the valve body (2) to form the cavity; the air vent is arranged at the connection between the pressure cover (8) and the valve body (2).

3. The explosion-proof pressure relief valve according to claim 2, It is characterized in that A groove structure is provided on one side of the piston (4), and the middle hole (402) passes through the inner bottom of the groove structure; An annular groove (401) is provided on the other side of the piston (4), and the sealing ring (3) is arranged in the annular groove (401). When the piston (4) moves to a side close to the valve body (2), the sealing ring (3) abuts against the inner end surface of the through hole (202).

4. The explosion-proof pressure relief valve according to claim 3, It is characterized in that The film material (5) is attached to the inner bottom surface of the groove structure of the piston (4) and is used to cover the inner end of the middle hole (402); A fixing ring is provided on the membrane material (5), and one end of the elastic member (7) abuts against the fixing ring (6).

5. The explosion-proof pressure relief valve according to claim 4, It is characterized in that Both ends of the central hole (402) are chamfered.

6. The explosion-proof pressure relief valve according to claim 5, It is characterized in that A step groove is also provided at one end of the middle hole (402) located on the inner bottom surface of the groove structure.

7. The explosion-proof pressure relief valve according to claim 2, It is characterized in that The valve body (2) is used to connect one end of the gland (8) and is provided with a protrusion and a recess along the circumferential direction. The protrusion is plug-connected with the gland, and a gap is formed between the recess and the end surface of the gland to form the air vent.

8. The explosion-proof pressure relief valve according to any one of claims 1 to 7, It is characterized in that A column is provided on the outside of the valve body, the outside of the column is a threaded structure, and the through hole (202) passes through the column; an annular seal (1) is provided at the connection between the column and the valve body, which is used to seal the opening of the closed structure and the column.

9. A closed structure, It is characterized in that Including the explosion-proof pressure relief valve according to any one of claims 1 to 8.

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